Adding upstream version 7.0.14-dfsg.upstream/7.0.14-dfsg

Signed-off-by: Daniel Baumann <daniel.baumann@progress-linux.org>

8 files changed, 12915 insertions, 0 deletions

diff --git a/src/VBox/Main/xml/Makefile.kup b/src/VBox/Main/xml/Makefile.kup
new file mode 100644
index 00000000..e69de29b
--- /dev/null
+++ b/src/VBox/Main/xml/Makefile.kup
diff --git a/src/VBox/Main/xml/SchemaDefs.xsl b/src/VBox/Main/xml/SchemaDefs.xsl
new file mode 100644
index 00000000..262ea41a
--- /dev/null
+++ b/src/VBox/Main/xml/SchemaDefs.xsl
@@ -0,0 +1,246 @@
+<?xml version="1.0"?>
+
+<!--
+ *  A template to generate a header that will contain some important constraints
+ *  extracted from the VirtualBox XML Schema (VirtualBox-settings-*.xsd).
+ *  The output file name must be SchemaDefs.h.
+ *
+ *  This template depends on XML Schema structure (type names and constraints)
+ *  and should be reviewed on every Schema change.
+-->
+<!--
+    Copyright (C) 2006-2023 Oracle and/or its affiliates.
+
+    This file is part of VirtualBox base platform packages, as
+    available from https://www.virtualbox.org.
+
+    This program is free software; you can redistribute it and/or
+    modify it under the terms of the GNU General Public License
+    as published by the Free Software Foundation, in version 3 of the
+    License.
+
+    This program is distributed in the hope that it will be useful, but
+    WITHOUT ANY WARRANTY; without even the implied warranty of
+    MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
+    General Public License for more details.
+
+    You should have received a copy of the GNU General Public License
+    along with this program; if not, see <https://www.gnu.org/licenses>.
+
+    SPDX-License-Identifier: GPL-3.0-only
+-->
+
+<xsl:stylesheet version="1.0"
+  xmlns:xsl="http://www.w3.org/1999/XSL/Transform"
+  xmlns:xsd="http://www.w3.org/2001/XMLSchema"
+>
+<xsl:output method="text"/>
+
+<xsl:strip-space elements="*"/>
+
+<xsl:param name="mode" expr=''/>
+
+<!--
+//  helpers
+////////////////////////////////////////////////////////////////////////////////
+-->
+
+<!--
+ *  Extract the specified value and assign it to an enum member with the given
+ *  name
+-->
+<xsl:template name="defineEnumMember">
+    <xsl:param name="member"/>
+    <xsl:param name="select"/>
+    <xsl:if test="$select">
+      <xsl:value-of select="concat('        ', $member, ' = ', $select, ',&#x0A;')"/>
+    </xsl:if>
+</xsl:template>
+
+<!--
+//  templates
+////////////////////////////////////////////////////////////////////////////////
+-->
+
+<!--
+ *  shut down all implicit templates
+-->
+<xsl:template match="*"/>
+<xsl:template match="*" mode="declare"/>
+<xsl:template match="*" mode="declare.enum"/>
+<xsl:template match="*" mode="define"/>
+
+<xsl:template match="/">
+  <xsl:choose>
+    <xsl:when test="$mode='declare'">
+      <xsl:apply-templates select="/" mode="declare"/>
+    </xsl:when>
+    <xsl:when test="$mode='define'">
+      <xsl:apply-templates select="/" mode="define"/>
+    </xsl:when>
+    <xsl:otherwise>
+      <xsl:message terminate="yes">
+Value '<xsl:value-of select="$mode"/>' of parameter 'mode' is invalid!
+      </xsl:message>
+    </xsl:otherwise>
+  </xsl:choose>
+</xsl:template>
+
+<!--
+ * - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - -
+ *  declare mode (C++ header file)
+ * - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - -
+-->
+
+<xsl:template match="/" mode="declare">
+<xsl:text>
+/*
+ *  DO NOT EDIT.
+ *
+ *  This header is automatically generated from the VirtualBox XML Settings
+ *  Schema and contains selected schema constraints declared in C++.
+ */
+
+#ifndef ____H_SCHEMADEFS
+#define ____H_SCHEMADEFS
+
+namespace SchemaDefs
+{
+    enum
+    {
+</xsl:text>
+
+  <xsl:apply-templates select="xsd:schema" mode="declare.enum"/>
+
+<xsl:text>        DummyTerminator
+    };
+</xsl:text>
+
+<xsl:apply-templates select="xsd:schema" mode="declare"/>
+
+<xsl:text>}
+
+#endif // !____H_SCHEMADEFS
+</xsl:text>
+</xsl:template>
+
+<!--
+ *  enumeration values
+-->
+<xsl:template match="xsd:schema" mode="declare.enum">
+
+  <!-- process include statements -->
+  <xsl:for-each select="xsd:include">
+    <xsl:apply-templates select="document(@schemaLocation)/xsd:schema" mode="declare.enum"/>
+  </xsl:for-each>
+
+  <xsl:call-template name="defineEnumMember">
+    <xsl:with-param name="member" select="'MinGuestRAM'"/>
+    <xsl:with-param name="select" select="
+      xsd:complexType[@name='TMemory']/xsd:attribute[@name='RAMSize']//xsd:minInclusive/@value
+    "/>
+  </xsl:call-template>
+  <xsl:call-template name="defineEnumMember">
+    <xsl:with-param name="member" select="'MaxGuestRAM'"/>
+    <xsl:with-param name="select" select="
+      xsd:complexType[@name='TMemory']/xsd:attribute[@name='RAMSize']//xsd:maxInclusive/@value
+    "/>
+  </xsl:call-template>
+
+  <xsl:call-template name="defineEnumMember">
+    <xsl:with-param name="member" select="'MinGuestVRAM'"/>
+    <xsl:with-param name="select" select="
+      xsd:complexType[@name='TDisplay']/xsd:attribute[@name='VRAMSize']//xsd:minInclusive/@value
+    "/>
+  </xsl:call-template>
+  <xsl:call-template name="defineEnumMember">
+    <xsl:with-param name="member" select="'MaxGuestVRAM'"/>
+    <xsl:with-param name="select" select="
+      xsd:complexType[@name='TDisplay']/xsd:attribute[@name='VRAMSize']//xsd:maxInclusive/@value
+    "/>
+  </xsl:call-template>
+
+  <xsl:call-template name="defineEnumMember">
+    <xsl:with-param name="member" select="'MinCPUCount'"/>
+    <xsl:with-param name="select" select="
+      xsd:simpleType[@name='TCPUCount']//xsd:minInclusive/@value
+    "/>
+  </xsl:call-template>
+  <xsl:call-template name="defineEnumMember">
+    <xsl:with-param name="member" select="'MaxCPUCount'"/>
+    <xsl:with-param name="select" select="
+      xsd:simpleType[@name='TCPUCount']//xsd:maxInclusive/@value
+    "/>
+  </xsl:call-template>
+
+  <xsl:call-template name="defineEnumMember">
+    <xsl:with-param name="member" select="'MaxGuestMonitors'"/>
+    <xsl:with-param name="select" select="
+      xsd:simpleType[@name='TMonitorCount']//xsd:maxInclusive/@value
+    "/>
+  </xsl:call-template>
+
+  <xsl:call-template name="defineEnumMember">
+    <xsl:with-param name="member" select="'SerialPortCount'"/>
+    <xsl:with-param name="select" select="
+      xsd:complexType[@name='TUARTPort']/xsd:attribute[@name='slot']//xsd:maxExclusive/@value
+    "/>
+  </xsl:call-template>
+
+  <xsl:call-template name="defineEnumMember">
+    <xsl:with-param name="member" select="'ParallelPortCount'"/>
+    <xsl:with-param name="select" select="
+      xsd:complexType[@name='TLPTPort']/xsd:attribute[@name='slot']//xsd:maxExclusive/@value
+    "/>
+  </xsl:call-template>
+
+  <xsl:call-template name="defineEnumMember">
+    <xsl:with-param name="member" select="'MaxBootPosition'"/>
+    <xsl:with-param name="select" select="
+      xsd:complexType[@name='TBoot']//xsd:element[@name='Order']//xsd:attribute[@name='position']//xsd:maxInclusive/@value
+    "/>
+  </xsl:call-template>
+
+  <xsl:call-template name="defineEnumMember">
+    <xsl:with-param name="member" select="'DefaultHardwareVersion'"/>
+    <xsl:with-param name="select" select="
+      xsd:complexType[@name='THardware']/xsd:attribute[@name='version']/@default
+    "/>
+  </xsl:call-template>
+
+</xsl:template>
+
+<!--
+ * - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - -
+ *  define mode (C++ source file)
+ * - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - -
+-->
+
+<xsl:template match="/" mode="define">
+<xsl:text>
+/*
+ *  DO NOT EDIT.
+ *
+ *  This source is automatically generated from the VirtualBox XML Settings
+ *  Schema and contains selected schema constraints defined in C++.
+ */
+
+#include "SchemaDefs.h"
+
+namespace SchemaDefs
+{
+</xsl:text>
+
+<xsl:apply-templates select="xsd:schema" mode="define"/>
+
+<xsl:text>}
+</xsl:text>
+</xsl:template>
+
+<!--
+ * - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - -
+ *  END
+ * - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - -
+-->
+
+</xsl:stylesheet>
diff --git a/src/VBox/Main/xml/Settings.cpp b/src/VBox/Main/xml/Settings.cpp
new file mode 100644
index 00000000..fa1c1d82
--- /dev/null
+++ b/src/VBox/Main/xml/Settings.cpp
@@ -0,0 +1,9735 @@
+/* $Id: Settings.cpp $ */
+/** @file
+ * Settings File Manipulation API.
+ *
+ * Two classes, MainConfigFile and MachineConfigFile, represent the VirtualBox.xml and
+ * machine XML files. They share a common ancestor class, ConfigFileBase, which shares
+ * functionality such as talking to the XML back-end classes and settings version management.
+ *
+ * The code can read all VirtualBox settings files version 1.3 and higher. That version was
+ * written by VirtualBox 2.0. It can write settings version 1.7 (used by VirtualBox 2.2 and
+ * 3.0) and 1.9 (used by VirtualBox 3.1) and newer ones obviously.
+ *
+ * The settings versions enum is defined in src/VBox/Main/idl/VirtualBox.xidl. To introduce
+ * a new settings version (should be necessary at most once per VirtualBox major release,
+ * if at all), add a new SettingsVersion value to that enum and grep for the previously
+ * highest value to see which code in here needs adjusting.
+ *
+ * Certainly ConfigFileBase::ConfigFileBase() will. Change VBOX_XML_VERSION below as well.
+ * VBOX_XML_VERSION does not have to be changed if the settings for a default VM do not
+ * touch newly introduced attributes or tags. It has the benefit that older VirtualBox
+ * versions do not trigger their "newer" code path.
+ *
+ * Once a new settings version has been added, these are the rules for introducing a new
+ * setting: If an XML element or attribute or value is introduced that was not present in
+ * previous versions, then settings version checks need to be introduced. See the
+ * SettingsVersion enumeration in src/VBox/Main/idl/VirtualBox.xidl for details about which
+ * version was used when.
+ *
+ * The settings versions checks are necessary because since version 3.1, VirtualBox no longer
+ * automatically converts XML settings files but only if necessary, that is, if settings are
+ * present that the old format does not support. If we write an element or attribute to a
+ * settings file of an older version, then an old VirtualBox (before 3.1) will attempt to
+ * validate it with XML schema, and that will certainly fail.
+ *
+ * So, to introduce a new setting:
+ *
+ *   1) Make sure the constructor of corresponding settings structure has a proper default.
+ *
+ *   2) In the settings reader method, try to read the setting; if it's there, great, if not,
+ *      the default value will have been set by the constructor. The rule is to be tolerant
+ *      here.
+ *
+ *   3) In MachineConfigFile::bumpSettingsVersionIfNeeded(), check if the new setting has
+ *      a non-default value (i.e. that differs from the constructor). If so, bump the
+ *      settings version to the current version so the settings writer (4) can write out
+ *      the non-default value properly.
+ *
+ *      So far a corresponding method for MainConfigFile has not been necessary since there
+ *      have been no incompatible changes yet.
+ *
+ *   4) In the settings writer method, write the setting _only_ if the current settings
+ *      version (stored in m->sv) is high enough. That is, for VirtualBox 4.0, write it
+ *      only if (m->sv >= SettingsVersion_v1_11).
+ *
+ *   5) You _must_ update xml/VirtualBox-settings.xsd to contain the new tags and attributes.
+ *      Check that settings file from before and after your change are validating properly.
+ *      Use "kmk testvalidsettings", it should not find any files which don't validate.
+ */
+
+/*
+ * Copyright (C) 2007-2023 Oracle and/or its affiliates.
+ *
+ * This file is part of VirtualBox base platform packages, as
+ * available from https://www.virtualbox.org.
+ *
+ * This program is free software; you can redistribute it and/or
+ * modify it under the terms of the GNU General Public License
+ * as published by the Free Software Foundation, in version 3 of the
+ * License.
+ *
+ * This program is distributed in the hope that it will be useful, but
+ * WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
+ * General Public License for more details.
+ *
+ * You should have received a copy of the GNU General Public License
+ * along with this program; if not, see <https://www.gnu.org/licenses>.
+ *
+ * SPDX-License-Identifier: GPL-3.0-only
+ */
+
+#define LOG_GROUP LOG_GROUP_MAIN
+#include "VBox/com/string.h"
+#include "VBox/settings.h"
+#include <iprt/base64.h>
+#include <iprt/cpp/lock.h>
+#include <iprt/cpp/utils.h>
+#include <iprt/cpp/xml.h>
+#include <iprt/ctype.h>
+#include <iprt/err.h>
+#include <iprt/file.h>
+#include <iprt/ldr.h>
+#include <iprt/process.h>
+#include <iprt/stream.h>
+#ifdef RT_OS_WINDOWS
+# include <iprt/system.h> /* For RTSystemGetNtVersion() / RTSYSTEM_MAKE_NT_VERSION. */
+#endif
+#include <iprt/uri.h>
+
+// Guest Properties validation.
+#include "VBox/HostServices/GuestPropertySvc.h"
+
+// generated header
+#include "SchemaDefs.h"
+
+#include "HashedPw.h"
+#include "LoggingNew.h"
+
+using namespace com;
+using namespace settings;
+
+////////////////////////////////////////////////////////////////////////////////
+//
+// Defines
+//
+////////////////////////////////////////////////////////////////////////////////
+
+/** VirtualBox XML settings namespace */
+#define VBOX_XML_NAMESPACE      "http://www.virtualbox.org/"
+
+/** VirtualBox XML schema location (relative URI) */
+#define VBOX_XML_SCHEMA "VirtualBox-settings.xsd"
+
+/** VirtualBox XML settings version number substring ("x.y")  */
+#define VBOX_XML_VERSION        "1.12"
+
+/** VirtualBox OVF settings import default version number substring ("x.y").
+ *
+ * Think twice before changing this, as all VirtualBox versions before 5.1
+ * wrote the settings version when exporting, but totally ignored it on
+ * importing (while it should have been a mandatory attribute), so 3rd party
+ * software out there creates OVF files with the VirtualBox specific settings
+ * but lacking the version attribute. This shouldn't happen any more, but
+ * breaking existing OVF files isn't nice. */
+#define VBOX_XML_IMPORT_VERSION "1.15"
+
+/** VirtualBox XML settings version platform substring */
+#if defined (RT_OS_DARWIN)
+#   define VBOX_XML_PLATFORM     "macosx"
+#elif defined (RT_OS_FREEBSD)
+#   define VBOX_XML_PLATFORM     "freebsd"
+#elif defined (RT_OS_LINUX)
+#   define VBOX_XML_PLATFORM     "linux"
+#elif defined (RT_OS_NETBSD)
+#   define VBOX_XML_PLATFORM     "netbsd"
+#elif defined (RT_OS_OPENBSD)
+#   define VBOX_XML_PLATFORM     "openbsd"
+#elif defined (RT_OS_OS2)
+#   define VBOX_XML_PLATFORM     "os2"
+#elif defined (RT_OS_SOLARIS)
+#   define VBOX_XML_PLATFORM     "solaris"
+#elif defined (RT_OS_WINDOWS)
+#   define VBOX_XML_PLATFORM     "windows"
+#else
+#   error Unsupported platform!
+#endif
+
+/** VirtualBox XML settings full version string ("x.y-platform") */
+#define VBOX_XML_VERSION_FULL   VBOX_XML_VERSION "-" VBOX_XML_PLATFORM
+
+/** VirtualBox OVF import default settings full version string ("x.y-platform") */
+#define VBOX_XML_IMPORT_VERSION_FULL   VBOX_XML_IMPORT_VERSION "-" VBOX_XML_PLATFORM
+
+////////////////////////////////////////////////////////////////////////////////
+//
+// Internal data
+//
+////////////////////////////////////////////////////////////////////////////////
+
+/**
+ * Opaque data structore for ConfigFileBase (only declared
+ * in header, defined only here).
+ */
+
+struct ConfigFileBase::Data
+{
+    Data()
+        : pDoc(NULL),
+          pelmRoot(NULL),
+          sv(SettingsVersion_Null),
+          svRead(SettingsVersion_Null)
+    {}
+
+    ~Data()
+    {
+        cleanup();
+    }
+
+    RTCString               strFilename;
+    bool                    fFileExists;
+
+    xml::Document           *pDoc;
+    xml::ElementNode        *pelmRoot;
+
+    com::Utf8Str            strSettingsVersionFull;     // e.g. "1.7-linux"
+    SettingsVersion_T       sv;                         // e.g. SettingsVersion_v1_7
+
+    SettingsVersion_T       svRead;                     // settings version that the original file had when it was read,
+                                                        // or SettingsVersion_Null if none
+
+    void copyFrom(const Data &d)
+    {
+        strFilename = d.strFilename;
+        fFileExists = d.fFileExists;
+        strSettingsVersionFull = d.strSettingsVersionFull;
+        sv = d.sv;
+        svRead = d.svRead;
+    }
+
+    void cleanup()
+    {
+        if (pDoc)
+        {
+            delete pDoc;
+            pDoc = NULL;
+            pelmRoot = NULL;
+        }
+    }
+};
+
+/**
+ * Private exception class (not in the header file) that makes
+ * throwing xml::LogicError instances easier. That class is public
+ * and should be caught by client code.
+ */
+class settings::ConfigFileError : public xml::LogicError
+{
+public:
+    ConfigFileError(const ConfigFileBase *file,
+                    const xml::Node *pNode,
+                    const char *pcszFormat, ...)
+        : xml::LogicError()
+    {
+        va_list args;
+        va_start(args, pcszFormat);
+        Utf8Str strWhat(pcszFormat, args);
+        va_end(args);
+
+        Utf8Str strLine;
+        if (pNode)
+            strLine = Utf8StrFmt(" (line %RU32)", pNode->getLineNumber());
+
+        const char *pcsz = strLine.c_str();
+        Utf8StrFmt str(N_("Error in %s%s -- %s"),
+                       file->m->strFilename.c_str(),
+                       (pcsz) ? pcsz : "",
+                       strWhat.c_str());
+
+        setWhat(str.c_str());
+    }
+};
+
+////////////////////////////////////////////////////////////////////////////////
+//
+// ConfigFileBase
+//
+////////////////////////////////////////////////////////////////////////////////
+
+/**
+ * Constructor. Allocates the XML internals, parses the XML file if
+ * pstrFilename is != NULL and reads the settings version from it.
+ * @param pstrFilename
+ */
+ConfigFileBase::ConfigFileBase(const com::Utf8Str *pstrFilename)
+    : m(new Data)
+{
+    m->fFileExists = false;
+
+    if (pstrFilename)
+    {
+        try
+        {
+            // reading existing settings file:
+            m->strFilename = *pstrFilename;
+
+            xml::XmlFileParser parser;
+            m->pDoc = new xml::Document;
+            parser.read(*pstrFilename,
+                        *m->pDoc);
+
+            m->fFileExists = true;
+
+            m->pelmRoot = m->pDoc->getRootElement();
+            if (!m->pelmRoot || !m->pelmRoot->nameEquals("VirtualBox"))
+                throw ConfigFileError(this, m->pelmRoot, N_("Root element in VirtualBox settings files must be \"VirtualBox\""));
+
+            if (!(m->pelmRoot->getAttributeValue("version", m->strSettingsVersionFull)))
+                throw ConfigFileError(this, m->pelmRoot, N_("Required VirtualBox/@version attribute is missing"));
+
+            LogRel(("Loading settings file \"%s\" with version \"%s\"\n", m->strFilename.c_str(), m->strSettingsVersionFull.c_str()));
+
+            m->sv = parseVersion(m->strSettingsVersionFull, m->pelmRoot);
+
+            // remember the settings version we read in case it gets upgraded later,
+            // so we know when to make backups
+            m->svRead = m->sv;
+        }
+        catch(...)
+        {
+            /*
+             * The destructor is not called when an exception is thrown in the constructor,
+             * so we have to do the cleanup here.
+             */
+            delete m;
+            m = NULL;
+            throw;
+        }
+    }
+    else
+    {
+        // creating new settings file:
+        m->strSettingsVersionFull = VBOX_XML_VERSION_FULL;
+        m->sv = SettingsVersion_v1_12;
+    }
+}
+
+ConfigFileBase::ConfigFileBase(const ConfigFileBase &other)
+    : m(new Data)
+{
+    copyBaseFrom(other);
+    m->strFilename = "";
+    m->fFileExists = false;
+}
+
+/**
+ * Clean up.
+ */
+ConfigFileBase::~ConfigFileBase()
+{
+    if (m)
+    {
+        delete m;
+        m = NULL;
+    }
+}
+
+/**
+ * Helper function to convert a MediaType enum value into string from.
+ * @param t
+ */
+/*static*/
+const char *ConfigFileBase::stringifyMediaType(MediaType t)
+{
+    switch (t)
+    {
+        case HardDisk:
+            return "hard disk";
+        case DVDImage:
+            return "DVD";
+        case FloppyImage:
+            return "floppy";
+        default:
+            AssertMsgFailed(("media type %d\n", t));
+            return "UNKNOWN";
+    }
+}
+
+/**
+ * Helper function that parses a full version number.
+ *
+ * Allow future versions but fail if file is older than 1.6. Throws on errors.
+ * @returns settings version
+ * @param strVersion
+ * @param pElm
+ */
+SettingsVersion_T ConfigFileBase::parseVersion(const Utf8Str &strVersion, const xml::ElementNode *pElm)
+{
+    SettingsVersion_T sv = SettingsVersion_Null;
+    if (strVersion.length() > 3)
+    {
+        const char *pcsz = strVersion.c_str();
+
+        uint32_t uMajor = 0;
+        char ch;
+        while (   (ch = *pcsz)
+               && RT_C_IS_DIGIT(ch) )
+        {
+            uMajor *= 10;
+            uMajor += (uint32_t)(ch - '0');
+            ++pcsz;
+        }
+
+        uint32_t uMinor = 0;
+        if (ch == '.')
+        {
+            pcsz++;
+            while (   (ch = *pcsz)
+                   && RT_C_IS_DIGIT(ch))
+            {
+                uMinor *= 10;
+                uMinor += (ULONG)(ch - '0');
+                ++pcsz;
+            }
+        }
+
+        if (uMajor == 1)
+        {
+            if (uMinor == 3)
+                sv = SettingsVersion_v1_3;
+            else if (uMinor == 4)
+                sv = SettingsVersion_v1_4;
+            else if (uMinor == 5)
+                sv = SettingsVersion_v1_5;
+            else if (uMinor == 6)
+                sv = SettingsVersion_v1_6;
+            else if (uMinor == 7)
+                sv = SettingsVersion_v1_7;
+            else if (uMinor == 8)
+                sv = SettingsVersion_v1_8;
+            else if (uMinor == 9)
+                sv = SettingsVersion_v1_9;
+            else if (uMinor == 10)
+                sv = SettingsVersion_v1_10;
+            else if (uMinor == 11)
+                sv = SettingsVersion_v1_11;
+            else if (uMinor == 12)
+                sv = SettingsVersion_v1_12;
+            else if (uMinor == 13)
+                sv = SettingsVersion_v1_13;
+            else if (uMinor == 14)
+                sv = SettingsVersion_v1_14;
+            else if (uMinor == 15)
+                sv = SettingsVersion_v1_15;
+            else if (uMinor == 16)
+                sv = SettingsVersion_v1_16;
+            else if (uMinor == 17)
+                sv = SettingsVersion_v1_17;
+            else if (uMinor == 18)
+                sv = SettingsVersion_v1_18;
+            else if (uMinor == 19)
+                sv = SettingsVersion_v1_19;
+            else if (uMinor > 19)
+                sv = SettingsVersion_Future;
+        }
+        else if (uMajor > 1)
+            sv = SettingsVersion_Future;
+
+        Log(("Parsed settings version %d.%d to enum value %d\n", uMajor, uMinor, sv));
+    }
+
+    if (sv == SettingsVersion_Null)
+        throw ConfigFileError(this, pElm, N_("Cannot handle settings version '%s'"), strVersion.c_str());
+
+    return sv;
+}
+
+/**
+ * Helper function that parses a UUID in string form into
+ * a com::Guid item. Accepts UUIDs both with and without
+ * "{}" brackets. Throws on errors.
+ * @param guid
+ * @param strUUID
+ * @param pElm
+ */
+void ConfigFileBase::parseUUID(Guid &guid,
+                               const Utf8Str &strUUID,
+                               const xml::ElementNode *pElm) const
+{
+    guid = strUUID.c_str();
+    if (guid.isZero())
+        throw ConfigFileError(this, pElm, N_("UUID \"%s\" has zero format"), strUUID.c_str());
+    else if (!guid.isValid())
+        throw ConfigFileError(this, pElm, N_("UUID \"%s\" has invalid format"), strUUID.c_str());
+}
+
+/**
+ * Parses the given string in str and attempts to treat it as an ISO
+ * date/time stamp to put into timestamp. Throws on errors.
+ * @param timestamp
+ * @param str
+ * @param pElm
+ */
+void ConfigFileBase::parseTimestamp(RTTIMESPEC &timestamp,
+                                    const com::Utf8Str &str,
+                                    const xml::ElementNode *pElm) const
+{
+    const char *pcsz = str.c_str();
+        //  yyyy-mm-ddThh:mm:ss
+        // "2009-07-10T11:54:03Z"
+        //  01234567890123456789
+        //            1
+    if (str.length() > 19)
+    {
+        // timezone must either be unspecified or 'Z' for UTC
+        if (    (pcsz[19])
+             && (pcsz[19] != 'Z')
+           )
+            throw ConfigFileError(this, pElm, N_("Cannot handle ISO timestamp '%s': is not UTC date"), str.c_str());
+
+        int32_t yyyy;
+        uint32_t mm, dd, hh, min, secs;
+        if (    (pcsz[4] == '-')
+             && (pcsz[7] == '-')
+             && (pcsz[10] == 'T')
+             && (pcsz[13] == ':')
+             && (pcsz[16] == ':')
+           )
+        {
+            int vrc;
+            if (    (RT_SUCCESS(vrc = RTStrToInt32Ex(pcsz, NULL, 0, &yyyy)))
+                        // could theoretically be negative but let's assume that nobody
+                        // created virtual machines before the Christian era
+                 && (RT_SUCCESS(vrc = RTStrToUInt32Ex(pcsz + 5, NULL, 0, &mm)))
+                 && (RT_SUCCESS(vrc = RTStrToUInt32Ex(pcsz + 8, NULL, 0, &dd)))
+                 && (RT_SUCCESS(vrc = RTStrToUInt32Ex(pcsz + 11, NULL, 0, &hh)))
+                 && (RT_SUCCESS(vrc = RTStrToUInt32Ex(pcsz + 14, NULL, 0, &min)))
+                 && (RT_SUCCESS(vrc = RTStrToUInt32Ex(pcsz + 17, NULL, 0, &secs)))
+               )
+            {
+                RTTIME time =
+                {
+                    yyyy,
+                    (uint8_t)mm,
+                    0,
+                    0,
+                    (uint8_t)dd,
+                    (uint8_t)hh,
+                    (uint8_t)min,
+                    (uint8_t)secs,
+                    0,
+                    RTTIME_FLAGS_TYPE_UTC,
+                    0
+                };
+                if (RTTimeNormalize(&time))
+                    if (RTTimeImplode(&timestamp, &time))
+                        return;
+            }
+
+            throw ConfigFileError(this, pElm, N_("Cannot parse ISO timestamp '%s': runtime error, %Rra"), str.c_str(), vrc);
+        }
+
+        throw ConfigFileError(this, pElm, N_("Cannot parse ISO timestamp '%s': invalid format"), str.c_str());
+    }
+}
+
+/**
+ * Helper function that parses a Base64 formatted string into a binary blob.
+ * @param binary
+ * @param str
+ * @param pElm
+ */
+void ConfigFileBase::parseBase64(IconBlob &binary,
+                                 const Utf8Str &str,
+                                 const xml::ElementNode *pElm) const
+{
+#define DECODE_STR_MAX _1M
+    const char* psz = str.c_str();
+    ssize_t cbOut = RTBase64DecodedSize(psz, NULL);
+    if (cbOut > DECODE_STR_MAX)
+        throw ConfigFileError(this, pElm, N_("Base64 encoded data too long (%d > %d)"), cbOut, DECODE_STR_MAX);
+    else if (cbOut < 0)
+        throw ConfigFileError(this, pElm, N_("Base64 encoded data '%s' invalid"), psz);
+    binary.resize((size_t)cbOut);
+    int vrc = VINF_SUCCESS;
+    if (cbOut)
+        vrc = RTBase64Decode(psz, &binary.front(), (size_t)cbOut, NULL, NULL);
+    if (RT_FAILURE(vrc))
+    {
+        binary.resize(0);
+        throw ConfigFileError(this, pElm, N_("Base64 encoded data could not be decoded (%Rrc)"), vrc);
+    }
+}
+
+/**
+ * Helper to create a string for a RTTIMESPEC for writing out ISO timestamps.
+ * @param stamp
+ * @return
+ */
+com::Utf8Str ConfigFileBase::stringifyTimestamp(const RTTIMESPEC &stamp) const
+{
+    RTTIME time;
+    if (!RTTimeExplode(&time, &stamp))
+        throw ConfigFileError(this, NULL, N_("Timespec %lld ms is invalid"), RTTimeSpecGetMilli(&stamp));
+
+    return Utf8StrFmt("%04u-%02u-%02uT%02u:%02u:%02uZ",
+                      time.i32Year, time.u8Month, time.u8MonthDay,
+                      time.u8Hour, time.u8Minute, time.u8Second);
+}
+
+/**
+ * Helper to create a base64 encoded string out of a binary blob.
+ * @param str
+ * @param binary
+ * @throws std::bad_alloc and ConfigFileError
+ */
+void ConfigFileBase::toBase64(com::Utf8Str &str, const IconBlob &binary) const
+{
+    size_t cb = binary.size();
+    if (cb > 0)
+    {
+        size_t cchOut = RTBase64EncodedLength(cb);
+        str.reserve(cchOut + 1);
+        int vrc = RTBase64Encode(&binary.front(), cb, str.mutableRaw(), str.capacity(), NULL);
+        if (RT_FAILURE(vrc))
+            throw ConfigFileError(this, NULL, N_("Failed to convert binary data to base64 format (%Rrc)"), vrc);
+        str.jolt();
+    }
+}
+
+/**
+ * Helper method to read in an ExtraData subtree and stores its contents
+ * in the given map of extradata items. Used for both main and machine
+ * extradata (MainConfigFile and MachineConfigFile).
+ * @param elmExtraData
+ * @param map
+ */
+void ConfigFileBase::readExtraData(const xml::ElementNode &elmExtraData,
+                                   StringsMap &map)
+{
+    xml::NodesLoop nlLevel4(elmExtraData);
+    const xml::ElementNode *pelmExtraDataItem;
+    while ((pelmExtraDataItem = nlLevel4.forAllNodes()))
+    {
+        if (pelmExtraDataItem->nameEquals("ExtraDataItem"))
+        {
+            // <ExtraDataItem name="GUI/LastWindowPostion" value="97,88,981,858"/>
+            Utf8Str strName, strValue;
+            if (   pelmExtraDataItem->getAttributeValue("name", strName)
+                && pelmExtraDataItem->getAttributeValue("value", strValue) )
+                map[strName] = strValue;
+            else
+                throw ConfigFileError(this, pelmExtraDataItem, N_("Required ExtraDataItem/@name or @value attribute is missing"));
+        }
+    }
+}
+
+/**
+ * Reads \<USBDeviceFilter\> entries from under the given elmDeviceFilters node and
+ * stores them in the given linklist. This is in ConfigFileBase because it's used
+ * from both MainConfigFile (for host filters) and MachineConfigFile (for machine
+ * filters).
+ * @param elmDeviceFilters
+ * @param ll
+ */
+void ConfigFileBase::readUSBDeviceFilters(const xml::ElementNode &elmDeviceFilters,
+                                          USBDeviceFiltersList &ll)
+{
+    xml::NodesLoop nl1(elmDeviceFilters, "DeviceFilter");
+    const xml::ElementNode *pelmLevel4Child;
+    while ((pelmLevel4Child = nl1.forAllNodes()))
+    {
+        USBDeviceFilter flt;
+        flt.action = USBDeviceFilterAction_Ignore;
+        Utf8Str strAction;
+        if (   pelmLevel4Child->getAttributeValue("name", flt.strName)
+            && pelmLevel4Child->getAttributeValue("active", flt.fActive))
+        {
+            if (!pelmLevel4Child->getAttributeValue("vendorId", flt.strVendorId))
+                pelmLevel4Child->getAttributeValue("vendorid", flt.strVendorId);            // used before 1.3
+            if (!pelmLevel4Child->getAttributeValue("productId", flt.strProductId))
+                pelmLevel4Child->getAttributeValue("productid", flt.strProductId);          // used before 1.3
+            pelmLevel4Child->getAttributeValue("revision", flt.strRevision);
+            pelmLevel4Child->getAttributeValue("manufacturer", flt.strManufacturer);
+            pelmLevel4Child->getAttributeValue("product", flt.strProduct);
+            if (!pelmLevel4Child->getAttributeValue("serialNumber", flt.strSerialNumber))
+                pelmLevel4Child->getAttributeValue("serialnumber", flt.strSerialNumber);    // used before 1.3
+            pelmLevel4Child->getAttributeValue("port", flt.strPort);
+
+            // the next 2 are irrelevant for host USB objects
+            pelmLevel4Child->getAttributeValue("remote", flt.strRemote);
+            pelmLevel4Child->getAttributeValue("maskedInterfaces", flt.ulMaskedInterfaces);
+
+            // action is only used with host USB objects
+            if (pelmLevel4Child->getAttributeValue("action", strAction))
+            {
+                if (strAction == "Ignore")
+                    flt.action = USBDeviceFilterAction_Ignore;
+                else if (strAction == "Hold")
+                    flt.action = USBDeviceFilterAction_Hold;
+                else
+                    throw ConfigFileError(this, pelmLevel4Child, N_("Invalid value '%s' in DeviceFilter/@action attribute"), strAction.c_str());
+            }
+
+            ll.push_back(flt);
+        }
+    }
+}
+
+/**
+ * Reads a media registry entry from the main VirtualBox.xml file.
+ *
+ * Whereas the current media registry code is fairly straightforward, it was quite a mess
+ * with settings format before 1.4 (VirtualBox 2.0 used settings format 1.3). The elements
+ * in the media registry were much more inconsistent, and different elements were used
+ * depending on the type of device and image.
+ *
+ * @param t
+ * @param elmMedium
+ * @param med
+ */
+void ConfigFileBase::readMediumOne(MediaType t,
+                                   const xml::ElementNode &elmMedium,
+                                   Medium &med)
+{
+    // <HardDisk uuid="{5471ecdb-1ddb-4012-a801-6d98e226868b}" location="/mnt/innotek-unix/vdis/Windows XP.vdi" format="VDI" type="Normal">
+
+    Utf8Str strUUID;
+    if (!elmMedium.getAttributeValue("uuid", strUUID))
+        throw ConfigFileError(this, &elmMedium, N_("Required %s/@uuid attribute is missing"), elmMedium.getName());
+
+    parseUUID(med.uuid, strUUID, &elmMedium);
+
+    bool fNeedsLocation = true;
+
+    if (t == HardDisk)
+    {
+        if (m->sv < SettingsVersion_v1_4)
+        {
+            // here the system is:
+            //         <HardDisk uuid="{....}" type="normal">
+            //           <VirtualDiskImage filePath="/path/to/xxx.vdi"/>
+            //         </HardDisk>
+
+            fNeedsLocation = false;
+            bool fNeedsFilePath = true;
+            const xml::ElementNode *pelmImage;
+            if ((pelmImage = elmMedium.findChildElement("VirtualDiskImage")))
+                med.strFormat = "VDI";
+            else if ((pelmImage = elmMedium.findChildElement("VMDKImage")))
+                med.strFormat = "VMDK";
+            else if ((pelmImage = elmMedium.findChildElement("VHDImage")))
+                med.strFormat = "VHD";
+            else if ((pelmImage = elmMedium.findChildElement("ISCSIHardDisk")))
+            {
+                med.strFormat = "iSCSI";
+
+                fNeedsFilePath = false;
+                // location is special here: current settings specify an "iscsi://user@server:port/target/lun"
+                // string for the location and also have several disk properties for these, whereas this used
+                // to be hidden in several sub-elements before 1.4, so compose a location string and set up
+                // the properties:
+                med.strLocation = "iscsi://";
+                Utf8Str strUser, strServer, strPort, strTarget, strLun;
+                if (pelmImage->getAttributeValue("userName", strUser))
+                {
+                    med.strLocation.append(strUser);
+                    med.strLocation.append("@");
+                }
+                Utf8Str strServerAndPort;
+                if (pelmImage->getAttributeValue("server", strServer))
+                {
+                    strServerAndPort = strServer;
+                }
+                if (pelmImage->getAttributeValue("port", strPort))
+                {
+                    if (strServerAndPort.length())
+                        strServerAndPort.append(":");
+                    strServerAndPort.append(strPort);
+                }
+                med.strLocation.append(strServerAndPort);
+                if (pelmImage->getAttributeValue("target", strTarget))
+                {
+                    med.strLocation.append("/");
+                    med.strLocation.append(strTarget);
+                }
+                if (pelmImage->getAttributeValue("lun", strLun))
+                {
+                    med.strLocation.append("/");
+                    med.strLocation.append(strLun);
+                }
+
+                if (strServer.length() && strPort.length())
+                    med.properties["TargetAddress"] = strServerAndPort;
+                if (strTarget.length())
+                    med.properties["TargetName"] = strTarget;
+                if (strUser.length())
+                    med.properties["InitiatorUsername"] = strUser;
+                Utf8Str strPassword;
+                if (pelmImage->getAttributeValue("password", strPassword))
+                    med.properties["InitiatorSecret"] = strPassword;
+                if (strLun.length())
+                    med.properties["LUN"] = strLun;
+            }
+            else if ((pelmImage = elmMedium.findChildElement("CustomHardDisk")))
+            {
+                fNeedsFilePath = false;
+                fNeedsLocation = true;
+                    // also requires @format attribute, which will be queried below
+            }
+            else
+                throw ConfigFileError(this, &elmMedium, N_("Required %s/VirtualDiskImage element is missing"), elmMedium.getName());
+
+            if (fNeedsFilePath)
+            {
+                if (!(pelmImage->getAttributeValuePath("filePath", med.strLocation)))
+                    throw ConfigFileError(this, &elmMedium, N_("Required %s/@filePath attribute is missing"), elmMedium.getName());
+            }
+        }
+
+        if (med.strFormat.isEmpty())        // not set with 1.4 format above, or 1.4 Custom format?
+            if (!elmMedium.getAttributeValue("format", med.strFormat))
+                throw ConfigFileError(this, &elmMedium, N_("Required %s/@format attribute is missing"), elmMedium.getName());
+
+        if (!elmMedium.getAttributeValue("autoReset", med.fAutoReset))
+            med.fAutoReset = false;
+
+        Utf8Str strType;
+        if (elmMedium.getAttributeValue("type", strType))
+        {
+            // pre-1.4 used lower case, so make this case-insensitive
+            strType.toUpper();
+            if (strType == "NORMAL")
+                med.hdType = MediumType_Normal;
+            else if (strType == "IMMUTABLE")
+                med.hdType = MediumType_Immutable;
+            else if (strType == "WRITETHROUGH")
+                med.hdType = MediumType_Writethrough;
+            else if (strType == "SHAREABLE")
+                med.hdType = MediumType_Shareable;
+            else if (strType == "READONLY")
+                med.hdType = MediumType_Readonly;
+            else if (strType == "MULTIATTACH")
+                med.hdType = MediumType_MultiAttach;
+            else
+                throw ConfigFileError(this, &elmMedium, N_("HardDisk/@type attribute must be one of Normal, Immutable, Writethrough, Shareable, Readonly or MultiAttach"));
+        }
+    }
+    else
+    {
+        if (m->sv < SettingsVersion_v1_4)
+        {
+            // DVD and floppy images before 1.4 had "src" attribute instead of "location"
+            if (!elmMedium.getAttributeValue("src", med.strLocation))
+                throw ConfigFileError(this, &elmMedium, N_("Required %s/@src attribute is missing"), elmMedium.getName());
+
+            fNeedsLocation = false;
+        }
+
+        if (!elmMedium.getAttributeValue("format", med.strFormat))
+        {
+            // DVD and floppy images before 1.11 had no format attribute. assign the default.
+            med.strFormat = "RAW";
+        }
+
+        if (t == DVDImage)
+            med.hdType = MediumType_Readonly;
+        else if (t == FloppyImage)
+            med.hdType = MediumType_Writethrough;
+    }
+
+    if (fNeedsLocation)
+        // current files and 1.4 CustomHardDisk elements must have a location attribute
+        if (!elmMedium.getAttributeValue("location", med.strLocation))
+            throw ConfigFileError(this, &elmMedium, N_("Required %s/@location attribute is missing"), elmMedium.getName());
+
+    // 3.2 builds added Description as an attribute, read it silently
+    // and write it back as an element starting with 5.1.26
+    elmMedium.getAttributeValue("Description", med.strDescription);
+
+    xml::NodesLoop nlMediumChildren(elmMedium);
+    const xml::ElementNode *pelmMediumChild;
+    while ((pelmMediumChild = nlMediumChildren.forAllNodes()))
+    {
+        if (pelmMediumChild->nameEquals("Description"))
+            med.strDescription = pelmMediumChild->getValue();
+        else if (pelmMediumChild->nameEquals("Property"))
+        {
+            // handle medium properties
+            Utf8Str strPropName, strPropValue;
+            if (   pelmMediumChild->getAttributeValue("name", strPropName)
+                && pelmMediumChild->getAttributeValue("value", strPropValue) )
+                med.properties[strPropName] = strPropValue;
+            else
+                throw ConfigFileError(this, pelmMediumChild, N_("Required HardDisk/Property/@name or @value attribute is missing"));
+        }
+    }
+}
+
+/**
+ * Reads a media registry entry from the main VirtualBox.xml file and
+ * likewise for all children where applicable.
+ *
+ * @param t
+ * @param elmMedium
+ * @param med
+ */
+void ConfigFileBase::readMedium(MediaType t,
+                                const xml::ElementNode &elmMedium,
+                                Medium &med)
+{
+    std::list<const xml::ElementNode *> llElementsTodo;
+    llElementsTodo.push_back(&elmMedium);
+    std::list<Medium *> llSettingsTodo;
+    llSettingsTodo.push_back(&med);
+    std::list<uint32_t> llDepthsTodo;
+    llDepthsTodo.push_back(1);
+
+    while (llElementsTodo.size() > 0)
+    {
+        const xml::ElementNode *pElement = llElementsTodo.front();
+        llElementsTodo.pop_front();
+        Medium *pMed = llSettingsTodo.front();
+        llSettingsTodo.pop_front();
+        uint32_t depth = llDepthsTodo.front();
+        llDepthsTodo.pop_front();
+
+        if (depth > SETTINGS_MEDIUM_DEPTH_MAX)
+            throw ConfigFileError(this, pElement, N_("Maximum medium tree depth of %u exceeded"), SETTINGS_MEDIUM_DEPTH_MAX);
+
+        readMediumOne(t, *pElement, *pMed);
+
+        if (t != HardDisk)
+            return;
+
+        // load all children
+        xml::NodesLoop nl2(*pElement, m->sv >= SettingsVersion_v1_4 ? "HardDisk" : "DiffHardDisk");
+        const xml::ElementNode *pelmHDChild;
+        while ((pelmHDChild = nl2.forAllNodes()))
+        {
+            llElementsTodo.push_back(pelmHDChild);
+            pMed->llChildren.push_back(Medium::Empty);
+            llSettingsTodo.push_back(&pMed->llChildren.back());
+            llDepthsTodo.push_back(depth + 1);
+        }
+    }
+}
+
+/**
+ * Reads in the entire \<MediaRegistry\> chunk and stores its media in the lists
+ * of the given MediaRegistry structure.
+ *
+ * This is used in both MainConfigFile and MachineConfigFile since starting with
+ * VirtualBox 4.0, we can have media registries in both.
+ *
+ * For pre-1.4 files, this gets called with the \<DiskRegistry\> chunk instead.
+ *
+ * @param   elmMediaRegistry
+ * @param   mr
+ */
+void ConfigFileBase::readMediaRegistry(const xml::ElementNode &elmMediaRegistry,
+                                       MediaRegistry &mr)
+{
+    xml::NodesLoop nl1(elmMediaRegistry);
+    const xml::ElementNode *pelmChild1;
+    while ((pelmChild1 = nl1.forAllNodes()))
+    {
+        MediaType t = Error;
+        if (pelmChild1->nameEquals("HardDisks"))
+            t = HardDisk;
+        else if (pelmChild1->nameEquals("DVDImages"))
+            t = DVDImage;
+        else if (pelmChild1->nameEquals("FloppyImages"))
+            t = FloppyImage;
+        else
+            continue;
+
+        xml::NodesLoop nl2(*pelmChild1);
+        const xml::ElementNode *pelmMedium;
+        while ((pelmMedium = nl2.forAllNodes()))
+        {
+            if (   t == HardDisk
+                && (pelmMedium->nameEquals("HardDisk")))
+            {
+                mr.llHardDisks.push_back(Medium::Empty);
+                readMedium(t, *pelmMedium, mr.llHardDisks.back());
+            }
+            else if (   t == DVDImage
+                     && (pelmMedium->nameEquals("Image")))
+            {
+                mr.llDvdImages.push_back(Medium::Empty);
+                readMedium(t, *pelmMedium, mr.llDvdImages.back());
+            }
+            else if (   t == FloppyImage
+                     && (pelmMedium->nameEquals("Image")))
+            {
+                mr.llFloppyImages.push_back(Medium::Empty);
+                readMedium(t, *pelmMedium, mr.llFloppyImages.back());
+            }
+        }
+    }
+}
+
+/**
+ * This is common version for reading NAT port forward rule in per-_machine's_adapter_ and
+ * per-network approaches.
+ * Note: this function doesn't in fill given list from xml::ElementNodesList, because there is conflicting
+ * declaration in ovmfreader.h.
+ */
+void ConfigFileBase::readNATForwardRulesMap(const xml::ElementNode &elmParent, NATRulesMap &mapRules)
+{
+    xml::ElementNodesList plstRules;
+    elmParent.getChildElements(plstRules, "Forwarding");
+    for (xml::ElementNodesList::iterator pf = plstRules.begin(); pf != plstRules.end(); ++pf)
+    {
+        NATRule rule;
+        uint32_t port = 0;
+        (*pf)->getAttributeValue("name", rule.strName);
+        (*pf)->getAttributeValue("proto", (uint32_t&)rule.proto);
+        (*pf)->getAttributeValue("hostip", rule.strHostIP);
+        (*pf)->getAttributeValue("hostport", port);
+        rule.u16HostPort = (uint16_t)port;
+        (*pf)->getAttributeValue("guestip", rule.strGuestIP);
+        (*pf)->getAttributeValue("guestport", port);
+        rule.u16GuestPort = (uint16_t)port;
+        mapRules.insert(std::make_pair(rule.strName, rule));
+    }
+}
+
+void ConfigFileBase::readNATLoopbacks(const xml::ElementNode &elmParent, NATLoopbackOffsetList &llLoopbacks)
+{
+    xml::ElementNodesList plstLoopbacks;
+    elmParent.getChildElements(plstLoopbacks, "Loopback4");
+    for (xml::ElementNodesList::iterator lo = plstLoopbacks.begin();
+         lo != plstLoopbacks.end(); ++lo)
+    {
+        NATHostLoopbackOffset loopback;
+        (*lo)->getAttributeValue("address", loopback.strLoopbackHostAddress);
+        (*lo)->getAttributeValue("offset", (uint32_t&)loopback.u32Offset);
+        llLoopbacks.push_back(loopback);
+    }
+}
+
+
+/**
+ * Adds a "version" attribute to the given XML element with the
+ * VirtualBox settings version (e.g. "1.10-linux"). Used by
+ * the XML format for the root element and by the OVF export
+ * for the vbox:Machine element.
+ * @param elm
+ */
+void ConfigFileBase::setVersionAttribute(xml::ElementNode &elm)
+{
+    const char *pcszVersion = NULL;
+    switch (m->sv)
+    {
+        case SettingsVersion_v1_8:
+            pcszVersion = "1.8";
+            break;
+
+        case SettingsVersion_v1_9:
+            pcszVersion = "1.9";
+            break;
+
+        case SettingsVersion_v1_10:
+            pcszVersion = "1.10";
+            break;
+
+        case SettingsVersion_v1_11:
+            pcszVersion = "1.11";
+            break;
+
+        case SettingsVersion_v1_12:
+            pcszVersion = "1.12";
+            break;
+
+        case SettingsVersion_v1_13:
+            pcszVersion = "1.13";
+            break;
+
+        case SettingsVersion_v1_14:
+            pcszVersion = "1.14";
+            break;
+
+        case SettingsVersion_v1_15:
+            pcszVersion = "1.15";
+            break;
+
+        case SettingsVersion_v1_16:
+            pcszVersion = "1.16";
+            break;
+
+        case SettingsVersion_v1_17:
+            pcszVersion = "1.17";
+            break;
+
+        case SettingsVersion_v1_18:
+            pcszVersion = "1.18";
+            break;
+
+        case SettingsVersion_v1_19:
+            pcszVersion = "1.19";
+            break;
+
+        default:
+            // catch human error: the assertion below will trigger in debug
+            // or dbgopt builds, so hopefully this will get noticed sooner in
+            // the future, because it's easy to forget top update something.
+            AssertMsg(m->sv <= SettingsVersion_v1_7, ("Settings.cpp: unexpected settings version %d, unhandled future version?\n", m->sv));
+            // silently upgrade if this is less than 1.7 because that's the oldest we can write
+            if (m->sv <= SettingsVersion_v1_7)
+            {
+                pcszVersion = "1.7";
+                m->sv = SettingsVersion_v1_7;
+            }
+            else
+            {
+                // This is reached for SettingsVersion_Future and forgotten
+                // settings version after SettingsVersion_v1_7, which should
+                // not happen (see assertion above). Set the version to the
+                // latest known version, to minimize loss of information, but
+                // as we can't predict the future we have to use some format
+                // we know, and latest should be the best choice. Note that
+                // for "forgotten settings" this may not be the best choice,
+                // but as it's an omission of someone who changed this file
+                // it's the only generic possibility.
+                pcszVersion = "1.19";
+                m->sv = SettingsVersion_v1_19;
+            }
+            break;
+    }
+
+    m->strSettingsVersionFull = Utf8StrFmt("%s-%s",
+                                           pcszVersion,
+                                           VBOX_XML_PLATFORM);  // e.g. "linux"
+    elm.setAttribute("version", m->strSettingsVersionFull);
+}
+
+
+/**
+ * Creates a special backup file in case there is a version
+ * bump, so that it is possible to go back to the previous
+ * state. This is done only once (not for every settings
+ * version bump), when the settings version is newer than
+ * the version read from the config file. Must be called
+ * before ConfigFileBase::createStubDocument, because that
+ * method may alter information which this method needs.
+ */
+void ConfigFileBase::specialBackupIfFirstBump()
+{
+    // Since this gets called before the XML document is actually written out,
+    // this is where we must check whether we're upgrading the settings version
+    // and need to make a backup, so the user can go back to an earlier
+    // VirtualBox version and recover his old settings files.
+    if (    (m->svRead != SettingsVersion_Null)     // old file exists?
+         && (m->svRead < m->sv)                     // we're upgrading?
+       )
+    {
+        // compose new filename: strip off trailing ".xml"/".vbox"
+        Utf8Str strFilenameNew;
+        Utf8Str strExt = ".xml";
+        if (m->strFilename.endsWith(".xml"))
+            strFilenameNew = m->strFilename.substr(0, m->strFilename.length() - 4);
+        else if (m->strFilename.endsWith(".vbox"))
+        {
+            strFilenameNew = m->strFilename.substr(0, m->strFilename.length() - 5);
+            strExt = ".vbox";
+        }
+
+        // and append something like "-1.3-linux.xml"
+        strFilenameNew.append("-");
+        strFilenameNew.append(m->strSettingsVersionFull);       // e.g. "1.3-linux"
+        strFilenameNew.append(strExt);                          // .xml for main config, .vbox for machine config
+
+        // Copying the file cannot be avoided, as doing tricks with renaming
+        // causes trouble on OS X with aliases (which follow the rename), and
+        // on all platforms there is a risk of "losing" the VM config when
+        // running out of space, as a rename here couldn't be rolled back.
+        // Ignoring all errors besides running out of space is intentional, as
+        // we don't want to do anything if the file already exists.
+        int vrc = RTFileCopy(m->strFilename.c_str(), strFilenameNew.c_str());
+        if (RT_UNLIKELY(vrc == VERR_DISK_FULL))
+            throw ConfigFileError(this, NULL, N_("Cannot create settings backup file when upgrading to a newer settings format"));
+
+        // do this only once
+        m->svRead = SettingsVersion_Null;
+    }
+}
+
+/**
+ * Creates a new stub xml::Document in the m->pDoc member with the
+ * root "VirtualBox" element set up. This is used by both
+ * MainConfigFile and MachineConfigFile at the beginning of writing
+ * out their XML.
+ *
+ * Before calling this, it is the responsibility of the caller to
+ * set the "sv" member to the required settings version that is to
+ * be written. For newly created files, the settings version will be
+ * recent (1.12 or later if necessary); for files read in from disk
+ * earlier, it will be the settings version indicated in the file.
+ * However, this method will silently make sure that the settings
+ * version is always at least 1.7 and change it if necessary, since
+ * there is no write support for earlier settings versions.
+ */
+void ConfigFileBase::createStubDocument()
+{
+    Assert(m->pDoc == NULL);
+    m->pDoc = new xml::Document;
+
+    m->pelmRoot = m->pDoc->createRootElement("VirtualBox",
+                                             "\n"
+                                             "** DO NOT EDIT THIS FILE.\n"
+                                             "** If you make changes to this file while any VirtualBox related application\n"
+                                             "** is running, your changes will be overwritten later, without taking effect.\n"
+                                             "** Use VBoxManage or the VirtualBox Manager GUI to make changes.\n"
+);
+    m->pelmRoot->setAttribute("xmlns", VBOX_XML_NAMESPACE);
+    // Have the code for producing a proper schema reference. Not used by most
+    // tools, so don't bother doing it. The schema is not on the server anyway.
+#ifdef VBOX_WITH_SETTINGS_SCHEMA
+    m->pelmRoot->setAttribute("xmlns:xsi", "http://www.w3.org/2001/XMLSchema-instance");
+    m->pelmRoot->setAttribute("xsi:schemaLocation", VBOX_XML_NAMESPACE " " VBOX_XML_SCHEMA);
+#endif
+
+    // add settings version attribute to root element, update m->strSettingsVersionFull
+    setVersionAttribute(*m->pelmRoot);
+
+    LogRel(("Saving settings file \"%s\" with version \"%s\"\n", m->strFilename.c_str(), m->strSettingsVersionFull.c_str()));
+}
+
+/**
+ * Creates an \<ExtraData\> node under the given parent element with
+ * \<ExtraDataItem\> childern according to the contents of the given
+ * map.
+ *
+ * This is in ConfigFileBase because it's used in both MainConfigFile
+ * and MachineConfigFile, which both can have extradata.
+ *
+ * @param elmParent
+ * @param me
+ */
+void ConfigFileBase::buildExtraData(xml::ElementNode &elmParent,
+                                    const StringsMap &me)
+{
+    if (me.size())
+    {
+        xml::ElementNode *pelmExtraData = elmParent.createChild("ExtraData");
+        for (StringsMap::const_iterator it = me.begin();
+             it != me.end();
+             ++it)
+        {
+            const Utf8Str &strName = it->first;
+            const Utf8Str &strValue = it->second;
+            xml::ElementNode *pelmThis = pelmExtraData->createChild("ExtraDataItem");
+            pelmThis->setAttribute("name", strName);
+            pelmThis->setAttribute("value", strValue);
+        }
+    }
+}
+
+/**
+ * Creates \<DeviceFilter\> nodes under the given parent element according to
+ * the contents of the given USBDeviceFiltersList. This is in ConfigFileBase
+ * because it's used in both MainConfigFile (for host filters) and
+ * MachineConfigFile (for machine filters).
+ *
+ * If fHostMode is true, this means that we're supposed to write filters
+ * for the IHost interface (respect "action", omit "strRemote" and
+ * "ulMaskedInterfaces" in struct USBDeviceFilter).
+ *
+ * @param elmParent
+ * @param ll
+ * @param fHostMode
+ */
+void ConfigFileBase::buildUSBDeviceFilters(xml::ElementNode &elmParent,
+                                           const USBDeviceFiltersList &ll,
+                                           bool fHostMode)
+{
+    for (USBDeviceFiltersList::const_iterator it = ll.begin();
+         it != ll.end();
+         ++it)
+    {
+        const USBDeviceFilter &flt = *it;
+        xml::ElementNode *pelmFilter = elmParent.createChild("DeviceFilter");
+        pelmFilter->setAttribute("name", flt.strName);
+        pelmFilter->setAttribute("active", flt.fActive);
+        if (flt.strVendorId.length())
+            pelmFilter->setAttribute("vendorId", flt.strVendorId);
+        if (flt.strProductId.length())
+            pelmFilter->setAttribute("productId", flt.strProductId);
+        if (flt.strRevision.length())
+            pelmFilter->setAttribute("revision", flt.strRevision);
+        if (flt.strManufacturer.length())
+            pelmFilter->setAttribute("manufacturer", flt.strManufacturer);
+        if (flt.strProduct.length())
+            pelmFilter->setAttribute("product", flt.strProduct);
+        if (flt.strSerialNumber.length())
+            pelmFilter->setAttribute("serialNumber", flt.strSerialNumber);
+        if (flt.strPort.length())
+            pelmFilter->setAttribute("port", flt.strPort);
+
+        if (fHostMode)
+        {
+            const char *pcsz =
+                (flt.action == USBDeviceFilterAction_Ignore) ? "Ignore"
+                : /*(flt.action == USBDeviceFilterAction_Hold) ?*/ "Hold";
+            pelmFilter->setAttribute("action", pcsz);
+        }
+        else
+        {
+            if (flt.strRemote.length())
+                pelmFilter->setAttribute("remote", flt.strRemote);
+            if (flt.ulMaskedInterfaces)
+                pelmFilter->setAttribute("maskedInterfaces", flt.ulMaskedInterfaces);
+        }
+    }
+}
+
+/**
+ * Creates a single \<HardDisk\> element for the given Medium structure
+ * and all child hard disks underneath. Called from MainConfigFile::write().
+ *
+ * @param t
+ * @param elmMedium
+ * @param med
+ */
+void ConfigFileBase::buildMedium(MediaType t,
+                                 xml::ElementNode &elmMedium,
+                                 const Medium &med)
+{
+    std::list<const Medium *> llSettingsTodo;
+    llSettingsTodo.push_back(&med);
+    std::list<xml::ElementNode *> llElementsTodo;
+    llElementsTodo.push_back(&elmMedium);
+    std::list<uint32_t> llDepthsTodo;
+    llDepthsTodo.push_back(1);
+
+    while (llSettingsTodo.size() > 0)
+    {
+        const Medium *pMed = llSettingsTodo.front();
+        llSettingsTodo.pop_front();
+        xml::ElementNode *pElement = llElementsTodo.front();
+        llElementsTodo.pop_front();
+        uint32_t depth = llDepthsTodo.front();
+        llDepthsTodo.pop_front();
+
+        if (depth > SETTINGS_MEDIUM_DEPTH_MAX)
+            throw ConfigFileError(this, pElement, N_("Maximum medium tree depth of %u exceeded"), SETTINGS_MEDIUM_DEPTH_MAX);
+
+        xml::ElementNode *pelmMedium;
+
+        if (t == HardDisk)
+            pelmMedium = pElement->createChild("HardDisk");
+        else
+            pelmMedium = pElement->createChild("Image");
+
+        pelmMedium->setAttribute("uuid", pMed->uuid.toStringCurly());
+
+        pelmMedium->setAttributePath("location", pMed->strLocation);
+
+        if (t == HardDisk || RTStrICmp(pMed->strFormat.c_str(), "RAW"))
+            pelmMedium->setAttribute("format", pMed->strFormat);
+        if (   t == HardDisk
+            && pMed->fAutoReset)
+            pelmMedium->setAttribute("autoReset", pMed->fAutoReset);
+        if (pMed->strDescription.length())
+            pelmMedium->createChild("Description")->addContent(pMed->strDescription);
+
+        for (StringsMap::const_iterator it = pMed->properties.begin();
+             it != pMed->properties.end();
+             ++it)
+        {
+            xml::ElementNode *pelmProp = pelmMedium->createChild("Property");
+            pelmProp->setAttribute("name", it->first);
+            pelmProp->setAttribute("value", it->second);
+        }
+
+        // only for base hard disks, save the type
+        if (depth == 1)
+        {
+            // no need to save the usual DVD/floppy medium types
+            if (   (   t != DVDImage
+                    || (   pMed->hdType != MediumType_Writethrough // shouldn't happen
+                        && pMed->hdType != MediumType_Readonly))
+                && (   t != FloppyImage
+                    || pMed->hdType != MediumType_Writethrough))
+            {
+                const char *pcszType =
+                    pMed->hdType == MediumType_Normal ? "Normal" :
+                    pMed->hdType == MediumType_Immutable ? "Immutable" :
+                    pMed->hdType == MediumType_Writethrough ? "Writethrough" :
+                    pMed->hdType == MediumType_Shareable ? "Shareable" :
+                    pMed->hdType == MediumType_Readonly ? "Readonly" :
+                    pMed->hdType == MediumType_MultiAttach ? "MultiAttach" :
+                    "INVALID";
+                pelmMedium->setAttribute("type", pcszType);
+            }
+        }
+
+        /* save all children */
+        MediaList::const_iterator itBegin = pMed->llChildren.begin();
+        MediaList::const_iterator itEnd = pMed->llChildren.end();
+        for (MediaList::const_iterator it = itBegin; it != itEnd; ++it)
+        {
+            llSettingsTodo.push_back(&*it);
+            llElementsTodo.push_back(pelmMedium);
+            llDepthsTodo.push_back(depth + 1);
+        }
+    }
+}
+
+/**
+ * Creates a \<MediaRegistry\> node under the given parent and writes out all
+ * hard disks and DVD and floppy images from the lists in the given MediaRegistry
+ * structure under it.
+ *
+ * This is used in both MainConfigFile and MachineConfigFile since starting with
+ * VirtualBox 4.0, we can have media registries in both.
+ *
+ * @param elmParent
+ * @param mr
+ */
+void ConfigFileBase::buildMediaRegistry(xml::ElementNode &elmParent,
+                                        const MediaRegistry &mr)
+{
+    if (mr.llHardDisks.size() == 0 && mr.llDvdImages.size() == 0 && mr.llFloppyImages.size() == 0)
+        return;
+
+    xml::ElementNode *pelmMediaRegistry = elmParent.createChild("MediaRegistry");
+
+    if (mr.llHardDisks.size())
+    {
+        xml::ElementNode *pelmHardDisks = pelmMediaRegistry->createChild("HardDisks");
+        for (MediaList::const_iterator it = mr.llHardDisks.begin();
+             it != mr.llHardDisks.end();
+             ++it)
+        {
+            buildMedium(HardDisk, *pelmHardDisks, *it);
+        }
+    }
+
+    if (mr.llDvdImages.size())
+    {
+        xml::ElementNode *pelmDVDImages = pelmMediaRegistry->createChild("DVDImages");
+        for (MediaList::const_iterator it = mr.llDvdImages.begin();
+             it != mr.llDvdImages.end();
+             ++it)
+        {
+            buildMedium(DVDImage, *pelmDVDImages, *it);
+        }
+    }
+
+    if (mr.llFloppyImages.size())
+    {
+        xml::ElementNode *pelmFloppyImages = pelmMediaRegistry->createChild("FloppyImages");
+        for (MediaList::const_iterator it = mr.llFloppyImages.begin();
+             it != mr.llFloppyImages.end();
+             ++it)
+        {
+            buildMedium(FloppyImage, *pelmFloppyImages, *it);
+        }
+    }
+}
+
+/**
+ * Serialize NAT port-forwarding rules in parent container.
+ * Note: it's responsibility of caller to create parent of the list tag.
+ * because this method used for serializing per-_mahine's_adapter_ and per-network approaches.
+ */
+void ConfigFileBase::buildNATForwardRulesMap(xml::ElementNode &elmParent, const NATRulesMap &mapRules)
+{
+    for (NATRulesMap::const_iterator r = mapRules.begin();
+         r != mapRules.end(); ++r)
+    {
+        xml::ElementNode *pelmPF;
+        pelmPF = elmParent.createChild("Forwarding");
+        const NATRule &nr = r->second;
+        if (nr.strName.length())
+            pelmPF->setAttribute("name", nr.strName);
+        pelmPF->setAttribute("proto", nr.proto);
+        if (nr.strHostIP.length())
+            pelmPF->setAttribute("hostip", nr.strHostIP);
+        if (nr.u16HostPort)
+            pelmPF->setAttribute("hostport", nr.u16HostPort);
+        if (nr.strGuestIP.length())
+            pelmPF->setAttribute("guestip", nr.strGuestIP);
+        if (nr.u16GuestPort)
+            pelmPF->setAttribute("guestport", nr.u16GuestPort);
+    }
+}
+
+
+void ConfigFileBase::buildNATLoopbacks(xml::ElementNode &elmParent, const NATLoopbackOffsetList &natLoopbackOffsetList)
+{
+    for (NATLoopbackOffsetList::const_iterator lo = natLoopbackOffsetList.begin();
+         lo != natLoopbackOffsetList.end(); ++lo)
+    {
+        xml::ElementNode *pelmLo;
+        pelmLo = elmParent.createChild("Loopback4");
+        pelmLo->setAttribute("address", (*lo).strLoopbackHostAddress);
+        pelmLo->setAttribute("offset", (*lo).u32Offset);
+    }
+}
+
+/**
+ * Cleans up memory allocated by the internal XML parser. To be called by
+ * descendant classes when they're done analyzing the DOM tree to discard it.
+ */
+void ConfigFileBase::clearDocument()
+{
+    m->cleanup();
+}
+
+/**
+ * Returns true only if the underlying config file exists on disk;
+ * either because the file has been loaded from disk, or it's been written
+ * to disk, or both.
+ * @return
+ */
+bool ConfigFileBase::fileExists()
+{
+    return m->fFileExists;
+}
+
+/**
+ * Returns the settings file version
+ *
+ * @returns Settings file version enum.
+ */
+SettingsVersion_T ConfigFileBase::getSettingsVersion()
+{
+    return m->sv;
+}
+
+
+/**
+ * Copies the base variables from another instance. Used by Machine::saveSettings
+ * so that the settings version does not get lost when a copy of the Machine settings
+ * file is made to see if settings have actually changed.
+ * @param b
+ */
+void ConfigFileBase::copyBaseFrom(const ConfigFileBase &b)
+{
+    m->copyFrom(*b.m);
+}
+
+////////////////////////////////////////////////////////////////////////////////
+//
+// Structures shared between Machine XML and VirtualBox.xml
+//
+////////////////////////////////////////////////////////////////////////////////
+
+
+/**
+ * Constructor. Needs to set sane defaults which stand the test of time.
+ */
+USBDeviceFilter::USBDeviceFilter() :
+    fActive(false),
+    action(USBDeviceFilterAction_Null),
+    ulMaskedInterfaces(0)
+{
+}
+
+/**
+ * Comparison operator. This gets called from MachineConfigFile::operator==,
+ * which in turn gets called from Machine::saveSettings to figure out whether
+ * machine settings have really changed and thus need to be written out to disk.
+ */
+bool USBDeviceFilter::operator==(const USBDeviceFilter &u) const
+{
+    return (this == &u)
+        || (   strName           == u.strName
+            && fActive           == u.fActive
+            && strVendorId       == u.strVendorId
+            && strProductId      == u.strProductId
+            && strRevision       == u.strRevision
+            && strManufacturer   == u.strManufacturer
+            && strProduct        == u.strProduct
+            && strSerialNumber   == u.strSerialNumber
+            && strPort           == u.strPort
+            && action            == u.action
+            && strRemote         == u.strRemote
+            && ulMaskedInterfaces == u.ulMaskedInterfaces);
+}
+
+/**
+ * Constructor. Needs to set sane defaults which stand the test of time.
+ */
+settings::Medium::Medium() :
+    fAutoReset(false),
+    hdType(MediumType_Normal)
+{
+}
+
+/**
+ * Comparison operator. This gets called from MachineConfigFile::operator==,
+ * which in turn gets called from Machine::saveSettings to figure out whether
+ * machine settings have really changed and thus need to be written out to disk.
+ */
+bool settings::Medium::operator==(const settings::Medium &m) const
+{
+    return (this == &m)
+        || (   uuid == m.uuid
+            && strLocation == m.strLocation
+            && strDescription == m.strDescription
+            && strFormat == m.strFormat
+            && fAutoReset == m.fAutoReset
+            && properties == m.properties
+            && hdType == m.hdType
+            && llChildren == m.llChildren);         // this is deep and recurses
+}
+
+const struct settings::Medium settings::Medium::Empty; /* default ctor is OK */
+
+/**
+ * Comparison operator. This gets called from MachineConfigFile::operator==,
+ * which in turn gets called from Machine::saveSettings to figure out whether
+ * machine settings have really changed and thus need to be written out to disk.
+ */
+bool MediaRegistry::operator==(const MediaRegistry &m) const
+{
+    return (this == &m)
+        || (   llHardDisks == m.llHardDisks
+            && llDvdImages == m.llDvdImages
+            && llFloppyImages == m.llFloppyImages);
+}
+
+/**
+ * Constructor. Needs to set sane defaults which stand the test of time.
+ */
+NATRule::NATRule() :
+    proto(NATProtocol_TCP),
+    u16HostPort(0),
+    u16GuestPort(0)
+{
+}
+
+/**
+ * Comparison operator. This gets called from MachineConfigFile::operator==,
+ * which in turn gets called from Machine::saveSettings to figure out whether
+ * machine settings have really changed and thus need to be written out to disk.
+ */
+bool NATRule::operator==(const NATRule &r) const
+{
+    return (this == &r)
+        || (   strName == r.strName
+            && proto == r.proto
+            && u16HostPort == r.u16HostPort
+            && strHostIP == r.strHostIP
+            && u16GuestPort == r.u16GuestPort
+            && strGuestIP == r.strGuestIP);
+}
+
+/**
+ * Constructor. Needs to set sane defaults which stand the test of time.
+ */
+NATHostLoopbackOffset::NATHostLoopbackOffset() :
+    u32Offset(0)
+{
+}
+
+/**
+ * Comparison operator. This gets called from MachineConfigFile::operator==,
+ * which in turn gets called from Machine::saveSettings to figure out whether
+ * machine settings have really changed and thus need to be written out to disk.
+ */
+bool NATHostLoopbackOffset::operator==(const NATHostLoopbackOffset &o) const
+{
+    return (this == &o)
+        || (   strLoopbackHostAddress == o.strLoopbackHostAddress
+            && u32Offset == o.u32Offset);
+}
+
+
+////////////////////////////////////////////////////////////////////////////////
+//
+// VirtualBox.xml structures
+//
+////////////////////////////////////////////////////////////////////////////////
+
+/**
+ * Constructor. Needs to set sane defaults which stand the test of time.
+ */
+SystemProperties::SystemProperties()
+    : uProxyMode(ProxyMode_System)
+    , uLogHistoryCount(3)
+    , fExclusiveHwVirt(true)
+{
+#if defined(RT_OS_DARWIN) || defined(RT_OS_WINDOWS) || defined(RT_OS_SOLARIS)
+    fExclusiveHwVirt = false;
+#endif
+}
+
+#ifdef VBOX_WITH_UPDATE_AGENT
+UpdateAgent::UpdateAgent()
+   : fEnabled(false)
+   , enmChannel(UpdateChannel_Stable)
+   , uCheckFreqSeconds(RT_SEC_1DAY)
+   , uCheckCount(0)
+{
+}
+#endif /* VBOX_WITH_UPDATE_AGENT */
+
+/**
+ * Constructor. Needs to set sane defaults which stand the test of time.
+ */
+DhcpOptValue::DhcpOptValue()
+    : strValue()
+    , enmEncoding(DHCPOptionEncoding_Normal)
+{
+}
+
+/**
+ * Non-standard constructor.
+ */
+DhcpOptValue::DhcpOptValue(const com::Utf8Str &aText, DHCPOptionEncoding_T aEncoding)
+    : strValue(aText)
+    , enmEncoding(aEncoding)
+{
+}
+
+/**
+ * Default constructor.
+ */
+DHCPGroupCondition::DHCPGroupCondition()
+    : fInclusive(true)
+    , enmType(DHCPGroupConditionType_MAC)
+    , strValue()
+{
+}
+
+/**
+ * Default constructor.
+ */
+DHCPConfig::DHCPConfig()
+    : mapOptions()
+    , secMinLeaseTime(0)
+    , secDefaultLeaseTime(0)
+    , secMaxLeaseTime(0)
+{
+}
+
+/**
+ * Default constructor.
+ */
+DHCPGroupConfig::DHCPGroupConfig()
+    : DHCPConfig()
+    , strName()
+    , vecConditions()
+{
+}
+
+/**
+ * Default constructor.
+ */
+DHCPIndividualConfig::DHCPIndividualConfig()
+    : DHCPConfig()
+    , strMACAddress()
+    , strVMName()
+    , uSlot(0)
+{
+}
+
+/**
+ * Constructor. Needs to set sane defaults which stand the test of time.
+ */
+DHCPServer::DHCPServer()
+    : fEnabled(false)
+{
+}
+
+/**
+ * Constructor. Needs to set sane defaults which stand the test of time.
+ */
+NATNetwork::NATNetwork() :
+    fEnabled(true),
+    fIPv6Enabled(false),
+    fAdvertiseDefaultIPv6Route(false),
+    fNeedDhcpServer(true),
+    u32HostLoopback6Offset(0)
+{
+}
+
+#ifdef VBOX_WITH_VMNET
+/**
+ * Constructor. Needs to set sane defaults which stand the test of time.
+ */
+HostOnlyNetwork::HostOnlyNetwork() :
+    strNetworkMask("255.255.255.0"),
+    strIPLower("192.168.56.1"),
+    strIPUpper("192.168.56.199"),
+    fEnabled(true)
+{
+    uuid.create();
+}
+#endif /* VBOX_WITH_VMNET */
+
+#ifdef VBOX_WITH_CLOUD_NET
+/**
+ * Constructor. Needs to set sane defaults which stand the test of time.
+ */
+CloudNetwork::CloudNetwork() :
+    strProviderShortName("OCI"),
+    strProfileName("Default"),
+    fEnabled(true)
+{
+}
+#endif /* VBOX_WITH_CLOUD_NET */
+
+
+
+////////////////////////////////////////////////////////////////////////////////
+//
+// MainConfigFile
+//
+////////////////////////////////////////////////////////////////////////////////
+
+/**
+ * Reads one \<MachineEntry\> from the main VirtualBox.xml file.
+ * @param elmMachineRegistry
+ */
+void MainConfigFile::readMachineRegistry(const xml::ElementNode &elmMachineRegistry)
+{
+    // <MachineEntry uuid="{ xxx }" src="   xxx "/>
+    xml::NodesLoop nl1(elmMachineRegistry);
+    const xml::ElementNode *pelmChild1;
+    while ((pelmChild1 = nl1.forAllNodes()))
+    {
+        if (pelmChild1->nameEquals("MachineEntry"))
+        {
+            MachineRegistryEntry mre;
+            Utf8Str strUUID;
+            if (   pelmChild1->getAttributeValue("uuid", strUUID)
+                && pelmChild1->getAttributeValue("src", mre.strSettingsFile) )
+            {
+                parseUUID(mre.uuid, strUUID, pelmChild1);
+                llMachines.push_back(mre);
+            }
+            else
+                throw ConfigFileError(this, pelmChild1, N_("Required MachineEntry/@uuid or @src attribute is missing"));
+        }
+    }
+}
+
+/**
+ * Builds the XML tree for the DHCP servers.
+ */
+void MainConfigFile::buildDHCPServers(xml::ElementNode &elmDHCPServers, DHCPServersList const &ll)
+{
+    for (DHCPServersList::const_iterator it = ll.begin(); it != ll.end(); ++it)
+    {
+        const DHCPServer &srv = *it;
+        xml::ElementNode *pElmThis = elmDHCPServers.createChild("DHCPServer");
+
+        pElmThis->setAttribute("networkName", srv.strNetworkName);
+        pElmThis->setAttribute("IPAddress", srv.strIPAddress);
+        DhcpOptConstIterator itOpt = srv.globalConfig.mapOptions.find(DHCPOption_SubnetMask);
+        if (itOpt != srv.globalConfig.mapOptions.end())
+            pElmThis->setAttribute("networkMask", itOpt->second.strValue);
+        pElmThis->setAttribute("lowerIP", srv.strIPLower);
+        pElmThis->setAttribute("upperIP", srv.strIPUpper);
+        pElmThis->setAttribute("enabled", (srv.fEnabled) ? 1 : 0);        // too bad we chose 1 vs. 0 here
+
+        /* We don't want duplicate validation check of networkMask here*/
+        if (srv.globalConfig.mapOptions.size() > (itOpt != srv.globalConfig.mapOptions.end() ? 1U : 0U))
+        {
+            xml::ElementNode *pElmOptions = pElmThis->createChild("Options");
+            buildDHCPOptions(*pElmOptions, srv.globalConfig, true);
+        }
+
+        for (DHCPGroupConfigVec::const_iterator itGroup = srv.vecGroupConfigs.begin();
+             itGroup != srv.vecGroupConfigs.end(); ++itGroup)
+        {
+            DHCPGroupConfig const &rGroupConfig = *itGroup;
+
+            xml::ElementNode *pElmGroup = pElmThis->createChild("Group");
+            pElmGroup->setAttribute("name", rGroupConfig.strName);
+            buildDHCPOptions(*pElmGroup, rGroupConfig, false);
+
+            for (DHCPGroupConditionVec::const_iterator itCond = rGroupConfig.vecConditions.begin();
+                 itCond != rGroupConfig.vecConditions.end(); ++itCond)
+            {
+                xml::ElementNode *pElmCondition = pElmGroup->createChild("Condition");
+                pElmCondition->setAttribute("inclusive", itCond->fInclusive);
+                pElmCondition->setAttribute("type", (int32_t)itCond->enmType);
+                pElmCondition->setAttribute("value", itCond->strValue);
+            }
+        }
+
+        for (DHCPIndividualConfigMap::const_iterator itHost = srv.mapIndividualConfigs.begin();
+             itHost != srv.mapIndividualConfigs.end(); ++itHost)
+        {
+            DHCPIndividualConfig const &rIndividualConfig = itHost->second;
+
+            xml::ElementNode *pElmConfig = pElmThis->createChild("Config");
+            if (rIndividualConfig.strMACAddress.isNotEmpty())
+                pElmConfig->setAttribute("MACAddress", rIndividualConfig.strMACAddress);
+            if (rIndividualConfig.strVMName.isNotEmpty())
+                pElmConfig->setAttribute("vm-name", rIndividualConfig.strVMName);
+            if (rIndividualConfig.uSlot != 0 || rIndividualConfig.strVMName.isNotEmpty())
+                pElmConfig->setAttribute("slot", rIndividualConfig.uSlot);
+            if (rIndividualConfig.strFixedAddress.isNotEmpty())
+                pElmConfig->setAttribute("fixedAddress", rIndividualConfig.strFixedAddress);
+            buildDHCPOptions(*pElmConfig, rIndividualConfig, false);
+        }
+     }
+}
+
+/**
+ * Worker for buildDHCPServers() that builds Options or Config element trees.
+ */
+void MainConfigFile::buildDHCPOptions(xml::ElementNode &elmOptions, DHCPConfig const &rConfig, bool fSkipSubnetMask)
+{
+    /* Generic (and optional) attributes on the Options or Config element: */
+    if (rConfig.secMinLeaseTime > 0)
+        elmOptions.setAttribute("secMinLeaseTime", rConfig.secMinLeaseTime);
+    if (rConfig.secDefaultLeaseTime > 0)
+        elmOptions.setAttribute("secDefaultLeaseTime", rConfig.secDefaultLeaseTime);
+    if (rConfig.secMaxLeaseTime > 0)
+        elmOptions.setAttribute("secMaxLeaseTime", rConfig.secMaxLeaseTime);
+    if (rConfig.strForcedOptions.isNotEmpty())
+        elmOptions.setAttribute("forcedOptions", rConfig.strForcedOptions);
+    if (rConfig.strSuppressedOptions.isNotEmpty())
+        elmOptions.setAttribute("suppressedOptions", rConfig.strSuppressedOptions);
+
+    /* The DHCP options are <Option> child elements: */
+    for (DhcpOptConstIterator it = rConfig.mapOptions.begin(); it != rConfig.mapOptions.end(); ++it)
+        if (it->first != DHCPOption_SubnetMask || !fSkipSubnetMask)
+        {
+            xml::ElementNode *pElmOption = elmOptions.createChild("Option");
+            pElmOption->setAttribute("name", it->first);
+            pElmOption->setAttribute("value", it->second.strValue);
+            if (it->second.enmEncoding != DHCPOptionEncoding_Normal)
+                pElmOption->setAttribute("encoding", (int32_t)it->second.enmEncoding);
+        }
+}
+
+/**
+ * Reads in the \<DHCPServers\> chunk.
+ * @param elmDHCPServers
+ */
+void MainConfigFile::readDHCPServers(const xml::ElementNode &elmDHCPServers)
+{
+    xml::NodesLoop nl1(elmDHCPServers);
+    const xml::ElementNode *pelmServer;
+    while ((pelmServer = nl1.forAllNodes()))
+    {
+        if (pelmServer->nameEquals("DHCPServer"))
+        {
+            DHCPServer srv;
+            if (   pelmServer->getAttributeValue("networkName", srv.strNetworkName)
+                && pelmServer->getAttributeValue("IPAddress", srv.strIPAddress)
+                && pelmServer->getAttributeValue("networkMask", srv.globalConfig.mapOptions[DHCPOption_SubnetMask].strValue)
+                && pelmServer->getAttributeValue("lowerIP", srv.strIPLower)
+                && pelmServer->getAttributeValue("upperIP", srv.strIPUpper)
+                && pelmServer->getAttributeValue("enabled", srv.fEnabled) )
+            {
+                /* Global options: */
+                const xml::ElementNode *pElmOptions;
+                xml::NodesLoop          nlOptions(*pelmServer, "Options");
+                while ((pElmOptions = nlOptions.forAllNodes()) != NULL) /** @todo this loop makes no sense, there can only be one \<Options\> child. */
+                    readDHCPOptions(srv.globalConfig, *pElmOptions, true /*fIgnoreSubnetMask*/);
+
+                /* Group configurations: */
+                xml::NodesLoop nlGroup(*pelmServer, "Group");
+                const xml::ElementNode *pElmGroup;
+                size_t i = 0;
+                while ((pElmGroup = nlGroup.forAllNodes()) != NULL)
+                {
+                    srv.vecGroupConfigs.push_back(DHCPGroupConfig());
+                    DHCPGroupConfig &rGroupConfig = srv.vecGroupConfigs.back();
+
+                    if (!pElmGroup->getAttributeValue("name", rGroupConfig.strName))
+                        rGroupConfig.strName.printf("Unamed Group #%u", ++i);
+
+                    readDHCPOptions(rGroupConfig, *pElmGroup, false /*fIgnoreSubnetMask*/);
+
+                    xml::NodesLoop nlCondition(*pElmGroup, "Condition");
+                    const xml::ElementNode *pElmCondition;
+                    while ((pElmCondition = nlCondition.forAllNodes()) != NULL)
+                    {
+                        rGroupConfig.vecConditions.push_back(DHCPGroupCondition());
+                        DHCPGroupCondition &rGroupCondition = rGroupConfig.vecConditions.back();
+
+                        if (!pElmCondition->getAttributeValue("inclusive", rGroupCondition.fInclusive))
+                            rGroupCondition.fInclusive = true;
+
+                        int32_t iType;
+                        if (!pElmCondition->getAttributeValue("type", iType))
+                            iType = DHCPGroupConditionType_MAC;
+                        rGroupCondition.enmType = (DHCPGroupConditionType_T)iType;
+
+                        pElmCondition->getAttributeValue("value", rGroupCondition.strValue);
+                    }
+                }
+
+                /* host specific configuration: */
+                xml::NodesLoop nlConfig(*pelmServer, "Config");
+                const xml::ElementNode *pElmConfig;
+                while ((pElmConfig = nlConfig.forAllNodes()) != NULL)
+                {
+                    com::Utf8Str strMACAddress;
+                    if (!pElmConfig->getAttributeValue("MACAddress", strMACAddress))
+                        strMACAddress.setNull();
+
+                    com::Utf8Str strVMName;
+                    if (!pElmConfig->getAttributeValue("vm-name", strVMName))
+                        strVMName.setNull();
+
+                    uint32_t uSlot;
+                    if (!pElmConfig->getAttributeValue("slot", uSlot))
+                        uSlot = 0;
+
+                    com::Utf8Str strKey;
+                    if (strVMName.isNotEmpty())
+                        strKey.printf("%s/%u", strVMName.c_str(), uSlot);
+                    else
+                        strKey.printf("%s/%u", strMACAddress.c_str(), uSlot);
+
+                    DHCPIndividualConfig &rIndividualConfig = srv.mapIndividualConfigs[strKey];
+                    rIndividualConfig.strMACAddress = strMACAddress;
+                    rIndividualConfig.strVMName     = strVMName;
+                    rIndividualConfig.uSlot         = uSlot;
+                    pElmConfig->getAttributeValue("fixedAddress", rIndividualConfig.strFixedAddress);
+
+                    readDHCPOptions(rIndividualConfig, *pElmConfig, false /*fIgnoreSubnetMask*/);
+                }
+
+                llDhcpServers.push_back(srv);
+            }
+            else
+                throw ConfigFileError(this, pelmServer, N_("Required DHCPServer/@networkName, @IPAddress, @networkMask, @lowerIP, @upperIP or @enabled attribute is missing"));
+        }
+    }
+}
+
+/**
+ * Worker for readDHCPServers that reads a configuration, either global,
+ * group or host (VM+NIC) specific.
+ */
+void MainConfigFile::readDHCPOptions(DHCPConfig &rConfig, const xml::ElementNode &elmConfig, bool fIgnoreSubnetMask)
+{
+    /* Generic (and optional) attributes on the Options or Config element: */
+    if (!elmConfig.getAttributeValue("secMinLeaseTime", rConfig.secMinLeaseTime))
+        rConfig.secMinLeaseTime = 0;
+    if (!elmConfig.getAttributeValue("secDefaultLeaseTime", rConfig.secDefaultLeaseTime))
+        rConfig.secDefaultLeaseTime = 0;
+    if (!elmConfig.getAttributeValue("secMaxLeaseTime", rConfig.secMaxLeaseTime))
+        rConfig.secMaxLeaseTime = 0;
+    if (!elmConfig.getAttributeValue("forcedOptions", rConfig.strForcedOptions))
+        rConfig.strSuppressedOptions.setNull();
+    if (!elmConfig.getAttributeValue("suppressedOptions", rConfig.strSuppressedOptions))
+        rConfig.strSuppressedOptions.setNull();
+
+    /* The DHCP options are <Option> child elements: */
+    xml::NodesLoop          nl2(elmConfig, "Option");
+    const xml::ElementNode *pElmOption;
+    while ((pElmOption = nl2.forAllNodes()) != NULL)
+    {
+        int32_t iOptName;
+        if (!pElmOption->getAttributeValue("name", iOptName))
+            continue;
+        DHCPOption_T OptName = (DHCPOption_T)iOptName;
+        if (OptName == DHCPOption_SubnetMask && fIgnoreSubnetMask)
+            continue;
+
+        com::Utf8Str strValue;
+        pElmOption->getAttributeValue("value", strValue);
+
+        int32_t iOptEnc;
+        if (!pElmOption->getAttributeValue("encoding", iOptEnc))
+            iOptEnc = DHCPOptionEncoding_Normal;
+
+        rConfig.mapOptions[OptName] = DhcpOptValue(strValue, (DHCPOptionEncoding_T)iOptEnc);
+    } /* end of forall("Option") */
+
+}
+
+/**
+ * Reads in the \<NATNetworks\> chunk.
+ * @param elmNATNetworks
+ */
+void MainConfigFile::readNATNetworks(const xml::ElementNode &elmNATNetworks)
+{
+    xml::NodesLoop nl1(elmNATNetworks);
+    const xml::ElementNode *pelmNet;
+    while ((pelmNet = nl1.forAllNodes()))
+    {
+        if (pelmNet->nameEquals("NATNetwork"))
+        {
+            NATNetwork net;
+            if (   pelmNet->getAttributeValue("networkName", net.strNetworkName)
+                && pelmNet->getAttributeValue("enabled", net.fEnabled)
+                && pelmNet->getAttributeValue("network", net.strIPv4NetworkCidr)
+                && pelmNet->getAttributeValue("ipv6", net.fIPv6Enabled)
+                && pelmNet->getAttributeValue("ipv6prefix", net.strIPv6Prefix)
+                && pelmNet->getAttributeValue("advertiseDefaultIPv6Route", net.fAdvertiseDefaultIPv6Route)
+                && pelmNet->getAttributeValue("needDhcp", net.fNeedDhcpServer) )
+            {
+                pelmNet->getAttributeValue("loopback6", net.u32HostLoopback6Offset);
+                const xml::ElementNode *pelmMappings;
+                if ((pelmMappings = pelmNet->findChildElement("Mappings")))
+                    readNATLoopbacks(*pelmMappings, net.llHostLoopbackOffsetList);
+
+                const xml::ElementNode *pelmPortForwardRules4;
+                if ((pelmPortForwardRules4 = pelmNet->findChildElement("PortForwarding4")))
+                    readNATForwardRulesMap(*pelmPortForwardRules4,
+                                           net.mapPortForwardRules4);
+
+                const xml::ElementNode *pelmPortForwardRules6;
+                if ((pelmPortForwardRules6 = pelmNet->findChildElement("PortForwarding6")))
+                    readNATForwardRulesMap(*pelmPortForwardRules6,
+                                           net.mapPortForwardRules6);
+
+                llNATNetworks.push_back(net);
+            }
+            else
+                throw ConfigFileError(this, pelmNet, N_("Required NATNetwork/@networkName, @gateway, @network,@advertiseDefaultIpv6Route , @needDhcp or @enabled attribute is missing"));
+        }
+    }
+}
+
+#ifdef VBOX_WITH_VMNET
+/**
+ * Reads in the \<HostOnlyNetworks\> chunk.
+ * @param elmHostOnlyNetworks
+ */
+void MainConfigFile::readHostOnlyNetworks(const xml::ElementNode &elmHostOnlyNetworks)
+{
+    xml::NodesLoop nl1(elmHostOnlyNetworks);
+    const xml::ElementNode *pelmNet;
+    while ((pelmNet = nl1.forAllNodes()))
+    {
+        if (pelmNet->nameEquals("HostOnlyNetwork"))
+        {
+            HostOnlyNetwork net;
+            Utf8Str strID;
+            if (   pelmNet->getAttributeValue("name", net.strNetworkName)
+                && pelmNet->getAttributeValue("mask", net.strNetworkMask)
+                && pelmNet->getAttributeValue("ipLower", net.strIPLower)
+                && pelmNet->getAttributeValue("ipUpper", net.strIPUpper)
+                && pelmNet->getAttributeValue("id", strID)
+                && pelmNet->getAttributeValue("enabled", net.fEnabled) )
+            {
+                parseUUID(net.uuid, strID, pelmNet);
+                llHostOnlyNetworks.push_back(net);
+            }
+            else
+                throw ConfigFileError(this, pelmNet, N_("Required HostOnlyNetwork/@name, @mask, @ipLower, @ipUpper, @id or @enabled attribute is missing"));
+        }
+    }
+}
+#endif /* VBOX_WITH_VMNET */
+
+#ifdef VBOX_WITH_CLOUD_NET
+/**
+ * Reads in the \<CloudNetworks\> chunk.
+ * @param elmCloudNetworks
+ */
+void MainConfigFile::readCloudNetworks(const xml::ElementNode &elmCloudNetworks)
+{
+    xml::NodesLoop nl1(elmCloudNetworks);
+    const xml::ElementNode *pelmNet;
+    while ((pelmNet = nl1.forAllNodes()))
+    {
+        if (pelmNet->nameEquals("CloudNetwork"))
+        {
+            CloudNetwork net;
+            if (   pelmNet->getAttributeValue("name", net.strNetworkName)
+                && pelmNet->getAttributeValue("provider", net.strProviderShortName)
+                && pelmNet->getAttributeValue("profile", net.strProfileName)
+                && pelmNet->getAttributeValue("id", net.strNetworkId)
+                && pelmNet->getAttributeValue("enabled", net.fEnabled) )
+            {
+                llCloudNetworks.push_back(net);
+            }
+            else
+                throw ConfigFileError(this, pelmNet, N_("Required CloudNetwork/@name, @provider, @profile, @id or @enabled attribute is missing"));
+        }
+    }
+}
+#endif /* VBOX_WITH_CLOUD_NET */
+
+/**
+ * Creates \<USBDeviceSource\> nodes under the given parent element according to
+ * the contents of the given USBDeviceSourcesList.
+ *
+ * @param elmParent
+ * @param ll
+ */
+void MainConfigFile::buildUSBDeviceSources(xml::ElementNode &elmParent,
+                                           const USBDeviceSourcesList &ll)
+{
+    for (USBDeviceSourcesList::const_iterator it = ll.begin();
+         it != ll.end();
+         ++it)
+    {
+        const USBDeviceSource &src = *it;
+        xml::ElementNode *pelmSource = elmParent.createChild("USBDeviceSource");
+        pelmSource->setAttribute("name", src.strName);
+        pelmSource->setAttribute("backend", src.strBackend);
+        pelmSource->setAttribute("address", src.strAddress);
+
+        /* Write the properties. */
+        for (StringsMap::const_iterator itProp = src.properties.begin();
+             itProp != src.properties.end();
+             ++itProp)
+        {
+            xml::ElementNode *pelmProp = pelmSource->createChild("Property");
+            pelmProp->setAttribute("name", itProp->first);
+            pelmProp->setAttribute("value", itProp->second);
+        }
+    }
+}
+
+/**
+ * Reads \<USBDeviceFilter\> entries from under the given elmDeviceFilters node and
+ * stores them in the given linklist. This is in ConfigFileBase because it's used
+ * from both MainConfigFile (for host filters) and MachineConfigFile (for machine
+ * filters).
+ * @param elmDeviceSources
+ * @param ll
+ */
+void MainConfigFile::readUSBDeviceSources(const xml::ElementNode &elmDeviceSources,
+                                          USBDeviceSourcesList &ll)
+{
+    xml::NodesLoop nl1(elmDeviceSources, "USBDeviceSource");
+    const xml::ElementNode *pelmChild;
+    while ((pelmChild = nl1.forAllNodes()))
+    {
+        USBDeviceSource src;
+
+        if (   pelmChild->getAttributeValue("name", src.strName)
+            && pelmChild->getAttributeValue("backend", src.strBackend)
+            && pelmChild->getAttributeValue("address", src.strAddress))
+        {
+            // handle medium properties
+            xml::NodesLoop nl2(*pelmChild, "Property");
+            const xml::ElementNode *pelmSrcChild;
+            while ((pelmSrcChild = nl2.forAllNodes()))
+            {
+                Utf8Str strPropName, strPropValue;
+                if (   pelmSrcChild->getAttributeValue("name", strPropName)
+                    && pelmSrcChild->getAttributeValue("value", strPropValue) )
+                    src.properties[strPropName] = strPropValue;
+                else
+                    throw ConfigFileError(this, pelmSrcChild, N_("Required USBDeviceSource/Property/@name or @value attribute is missing"));
+            }
+
+            ll.push_back(src);
+        }
+    }
+}
+
+/**
+ * Converts old style Proxy settings from ExtraData/UI section.
+ *
+ * Saves proxy settings directly to systemProperties structure.
+ *
+ * @returns true if conversion was successfull, false if not.
+ * @param strUIProxySettings The GUI settings string to convert.
+ */
+bool MainConfigFile::convertGuiProxySettings(const com::Utf8Str &strUIProxySettings)
+{
+    /*
+     * Possible variants:
+     *    - "ProxyAuto,proxyserver.url,1080,authDisabled,,"
+     *    - "ProxyDisabled,proxyserver.url,1080,authDisabled,,"
+     *    - "ProxyEnabled,proxyserver.url,1080,authDisabled,,"
+     *
+     * Note! We only need to bother with the first three fields as the last
+     *       three was never really used or ever actually passed to the HTTP
+     *       client code.
+     */
+    /* First field: The proxy mode. */
+    const char *psz = RTStrStripL(strUIProxySettings.c_str());
+    static const struct { const char *psz; size_t cch; ProxyMode_T enmMode; } s_aModes[] =
+    {
+        { RT_STR_TUPLE("ProxyAuto"),     ProxyMode_System },
+        { RT_STR_TUPLE("ProxyDisabled"), ProxyMode_NoProxy },
+        { RT_STR_TUPLE("ProxyEnabled"),  ProxyMode_Manual },
+    };
+    for (size_t i = 0; i < RT_ELEMENTS(s_aModes); i++)
+        if (RTStrNICmpAscii(psz, s_aModes[i].psz, s_aModes[i].cch) == 0)
+        {
+            systemProperties.uProxyMode = s_aModes[i].enmMode;
+            psz = RTStrStripL(psz + s_aModes[i].cch);
+            if (*psz == ',')
+            {
+                /* Second field: The proxy host, possibly fully fledged proxy URL. */
+                psz = RTStrStripL(psz + 1);
+                if (*psz != '\0' && *psz != ',')
+                {
+                    const char *pszEnd  = strchr(psz, ',');
+                    size_t      cchHost = pszEnd ? (size_t)(pszEnd - psz) : strlen(psz);
+                    while (cchHost > 0 && RT_C_IS_SPACE(psz[cchHost - 1]))
+                        cchHost--;
+                    systemProperties.strProxyUrl.assign(psz, cchHost);
+                    if (systemProperties.strProxyUrl.find("://") == RTCString::npos)
+                        systemProperties.strProxyUrl.replace(0, 0, "http://");
+
+                    /* Third field: The proxy port. Defaulted to 1080 for all proxies.
+                                    The new settings has type specific default ports.  */
+                    uint16_t uPort = 1080;
+                    if (pszEnd)
+                    {
+                        int vrc = RTStrToUInt16Ex(RTStrStripL(pszEnd + 1), NULL, 10, &uPort);
+                        if (RT_FAILURE(vrc))
+                            uPort = 1080;
+                    }
+                    RTURIPARSED Parsed;
+                    int vrc = RTUriParse(systemProperties.strProxyUrl.c_str(), &Parsed);
+                    if (RT_SUCCESS(vrc))
+                    {
+                        if (Parsed.uAuthorityPort == UINT32_MAX)
+                            systemProperties.strProxyUrl.appendPrintf(systemProperties.strProxyUrl.endsWith(":")
+                                                                      ? "%u" : ":%u", uPort);
+                    }
+                    else
+                    {
+                        LogRelFunc(("Dropping invalid proxy URL for %u: %s\n",
+                                    systemProperties.uProxyMode, systemProperties.strProxyUrl.c_str()));
+                        systemProperties.strProxyUrl.setNull();
+                    }
+                }
+                /* else: don't bother with the rest if we haven't got a host. */
+            }
+            if (   systemProperties.strProxyUrl.isEmpty()
+                && systemProperties.uProxyMode == ProxyMode_Manual)
+            {
+                systemProperties.uProxyMode = ProxyMode_System;
+                return false;
+            }
+            return true;
+        }
+    LogRelFunc(("Unknown proxy type: %s\n", psz));
+    return false;
+}
+
+/**
+ * Constructor.
+ *
+ * If pstrFilename is != NULL, this reads the given settings file into the member
+ * variables and various substructures and lists. Otherwise, the member variables
+ * are initialized with default values.
+ *
+ * Throws variants of xml::Error for I/O, XML and logical content errors, which
+ * the caller should catch; if this constructor does not throw, then the member
+ * variables contain meaningful values (either from the file or defaults).
+ *
+ * @param pstrFilename
+ */
+MainConfigFile::MainConfigFile(const Utf8Str *pstrFilename)
+    : ConfigFileBase(pstrFilename)
+{
+    if (pstrFilename)
+    {
+        // the ConfigFileBase constructor has loaded the XML file, so now
+        // we need only analyze what is in there
+        xml::NodesLoop nlRootChildren(*m->pelmRoot);
+        const xml::ElementNode *pelmRootChild;
+        bool fCopyProxySettingsFromExtraData = false;
+        while ((pelmRootChild = nlRootChildren.forAllNodes()))
+        {
+            if (pelmRootChild->nameEquals("Global"))
+            {
+                xml::NodesLoop nlGlobalChildren(*pelmRootChild);
+                const xml::ElementNode *pelmGlobalChild;
+                while ((pelmGlobalChild = nlGlobalChildren.forAllNodes()))
+                {
+                    if (pelmGlobalChild->nameEquals("SystemProperties"))
+                    {
+                        pelmGlobalChild->getAttributeValue("defaultMachineFolder", systemProperties.strDefaultMachineFolder);
+                        pelmGlobalChild->getAttributeValue("LoggingLevel", systemProperties.strLoggingLevel);
+                        pelmGlobalChild->getAttributeValue("defaultHardDiskFormat", systemProperties.strDefaultHardDiskFormat);
+                        if (!pelmGlobalChild->getAttributeValue("VRDEAuthLibrary", systemProperties.strVRDEAuthLibrary))
+                            // pre-1.11 used @remoteDisplayAuthLibrary instead
+                            pelmGlobalChild->getAttributeValue("remoteDisplayAuthLibrary", systemProperties.strVRDEAuthLibrary);
+                        pelmGlobalChild->getAttributeValue("webServiceAuthLibrary", systemProperties.strWebServiceAuthLibrary);
+                        pelmGlobalChild->getAttributeValue("defaultVRDEExtPack", systemProperties.strDefaultVRDEExtPack);
+                        pelmGlobalChild->getAttributeValue("defaultCryptoExtPack", systemProperties.strDefaultCryptoExtPack);
+                        pelmGlobalChild->getAttributeValue("LogHistoryCount", systemProperties.uLogHistoryCount);
+                        pelmGlobalChild->getAttributeValue("autostartDatabasePath", systemProperties.strAutostartDatabasePath);
+                        pelmGlobalChild->getAttributeValue("defaultFrontend", systemProperties.strDefaultFrontend);
+                        pelmGlobalChild->getAttributeValue("exclusiveHwVirt", systemProperties.fExclusiveHwVirt);
+                        if (!pelmGlobalChild->getAttributeValue("proxyMode", systemProperties.uProxyMode))
+                            fCopyProxySettingsFromExtraData = true;
+                        pelmGlobalChild->getAttributeValue("proxyUrl", systemProperties.strProxyUrl);
+                        pelmGlobalChild->getAttributeValue("LanguageId", systemProperties.strLanguageId);
+                    }
+#ifdef VBOX_WITH_UPDATE_AGENT
+                    else if (pelmGlobalChild->nameEquals("Updates"))
+                    {
+                        /* We keep the updates configuration as part of the host for now, as the API exposes the IHost::updateHost attribute,
+                         * but use an own "Updates" branch in the XML for better structurizing stuff in the future. */
+                        UpdateAgent &updateHost = host.updateHost;
+
+                        xml::NodesLoop nlLevel4(*pelmGlobalChild);
+                        const xml::ElementNode *pelmLevel4Child;
+                        while ((pelmLevel4Child = nlLevel4.forAllNodes()))
+                        {
+                            if (pelmLevel4Child->nameEquals("Host"))
+                            {
+                                pelmLevel4Child->getAttributeValue("enabled", updateHost.fEnabled);
+                                pelmLevel4Child->getAttributeValue("channel", (uint32_t&)updateHost.enmChannel);
+                                pelmLevel4Child->getAttributeValue("checkFreqSec", updateHost.uCheckFreqSeconds);
+                                pelmLevel4Child->getAttributeValue("repoUrl", updateHost.strRepoUrl);
+                                pelmLevel4Child->getAttributeValue("lastCheckDate", updateHost.strLastCheckDate);
+                                pelmLevel4Child->getAttributeValue("checkCount", updateHost.uCheckCount);
+                            }
+                            /** @todo Add update settings for ExtPack and Guest Additions here later. See @bugref{7983}. */
+                        }
+
+                        /* Global enabled switch for updates. Currently bound to host updates, as this is the only update we have so far. */
+                        pelmGlobalChild->getAttributeValue("enabled", updateHost.fEnabled);
+                    }
+#endif
+                    else if (pelmGlobalChild->nameEquals("ExtraData"))
+                        readExtraData(*pelmGlobalChild, mapExtraDataItems);
+                    else if (pelmGlobalChild->nameEquals("MachineRegistry"))
+                        readMachineRegistry(*pelmGlobalChild);
+                    else if (    (pelmGlobalChild->nameEquals("MediaRegistry"))
+                              || (    (m->sv < SettingsVersion_v1_4)
+                                   && (pelmGlobalChild->nameEquals("DiskRegistry"))
+                                 )
+                            )
+                        readMediaRegistry(*pelmGlobalChild, mediaRegistry);
+                    else if (pelmGlobalChild->nameEquals("NetserviceRegistry"))
+                    {
+                        xml::NodesLoop nlLevel4(*pelmGlobalChild);
+                        const xml::ElementNode *pelmLevel4Child;
+                        while ((pelmLevel4Child = nlLevel4.forAllNodes()))
+                        {
+                            if (pelmLevel4Child->nameEquals("DHCPServers"))
+                                readDHCPServers(*pelmLevel4Child);
+                            if (pelmLevel4Child->nameEquals("NATNetworks"))
+                                readNATNetworks(*pelmLevel4Child);
+#ifdef VBOX_WITH_VMNET
+                            if (pelmLevel4Child->nameEquals("HostOnlyNetworks"))
+                                readHostOnlyNetworks(*pelmLevel4Child);
+#endif /* VBOX_WITH_VMNET */
+#ifdef VBOX_WITH_CLOUD_NET
+                            if (pelmLevel4Child->nameEquals("CloudNetworks"))
+                                readCloudNetworks(*pelmLevel4Child);
+#endif /* VBOX_WITH_CLOUD_NET */
+                        }
+                    }
+                    else if (pelmGlobalChild->nameEquals("USBDeviceFilters"))
+                        readUSBDeviceFilters(*pelmGlobalChild, host.llUSBDeviceFilters);
+                    else if (pelmGlobalChild->nameEquals("USBDeviceSources"))
+                        readUSBDeviceSources(*pelmGlobalChild, host.llUSBDeviceSources);
+                }
+            } // end if (pelmRootChild->nameEquals("Global"))
+        }
+
+        if (fCopyProxySettingsFromExtraData)
+            for (StringsMap::const_iterator it = mapExtraDataItems.begin(); it != mapExtraDataItems.end(); ++it)
+                if (it->first.equals("GUI/ProxySettings"))
+                {
+                    convertGuiProxySettings(it->second);
+                    break;
+                }
+
+        clearDocument();
+    }
+
+    // DHCP servers were introduced with settings version 1.7; if we're loading
+    // from an older version OR this is a fresh install, then add one DHCP server
+    // with default settings
+    if (    (!llDhcpServers.size())
+         && (    (!pstrFilename)                    // empty VirtualBox.xml file
+              || (m->sv < SettingsVersion_v1_7)     // upgrading from before 1.7
+            )
+       )
+    {
+        DHCPServer srv;
+#ifdef RT_OS_WINDOWS
+        srv.strNetworkName = "HostInterfaceNetworking-VirtualBox Host-Only Ethernet Adapter";
+#else
+        srv.strNetworkName = "HostInterfaceNetworking-vboxnet0";
+#endif
+        srv.strIPAddress = "192.168.56.100";
+        srv.globalConfig.mapOptions[DHCPOption_SubnetMask] = DhcpOptValue("255.255.255.0");
+        srv.strIPLower = "192.168.56.101";
+        srv.strIPUpper = "192.168.56.254";
+        srv.fEnabled = true;
+        llDhcpServers.push_back(srv);
+    }
+}
+
+void MainConfigFile::bumpSettingsVersionIfNeeded()
+{
+#ifdef VBOX_WITH_VMNET
+    if (m->sv < SettingsVersion_v1_19)
+    {
+        // VirtualBox 7.0 adds support for host-only networks.
+        if (!llHostOnlyNetworks.empty())
+            m->sv = SettingsVersion_v1_19;
+    }
+#endif /* VBOX_WITH_VMNET */
+#ifdef VBOX_WITH_CLOUD_NET
+    if (m->sv < SettingsVersion_v1_18)
+    {
+        // VirtualBox 6.1 adds support for cloud networks.
+        if (!llCloudNetworks.empty())
+            m->sv = SettingsVersion_v1_18;
+    }
+#endif /* VBOX_WITH_CLOUD_NET */
+
+    if (m->sv < SettingsVersion_v1_16)
+    {
+        // VirtualBox 5.1 add support for additional USB device sources.
+        if (!host.llUSBDeviceSources.empty())
+            m->sv = SettingsVersion_v1_16;
+    }
+
+    if (m->sv < SettingsVersion_v1_14)
+    {
+        // VirtualBox 4.3 adds NAT networks.
+        if (   !llNATNetworks.empty())
+            m->sv = SettingsVersion_v1_14;
+    }
+}
+
+
+/**
+ * Called from the IVirtualBox interface to write out VirtualBox.xml. This
+ * builds an XML DOM tree and writes it out to disk.
+ */
+void MainConfigFile::write(const com::Utf8Str strFilename)
+{
+    bumpSettingsVersionIfNeeded();
+
+    m->strFilename = strFilename;
+    specialBackupIfFirstBump();
+    createStubDocument();
+
+    xml::ElementNode *pelmGlobal = m->pelmRoot->createChild("Global");
+
+    buildExtraData(*pelmGlobal, mapExtraDataItems);
+
+    xml::ElementNode *pelmMachineRegistry = pelmGlobal->createChild("MachineRegistry");
+    for (MachinesRegistry::const_iterator it = llMachines.begin();
+         it != llMachines.end();
+         ++it)
+    {
+        // <MachineEntry uuid="{5f102a55-a51b-48e3-b45a-b28d33469488}" src="/mnt/innotek-unix/vbox-machines/Windows 5.1 XP 1 (Office 2003)/Windows 5.1 XP 1 (Office 2003).xml"/>
+        const MachineRegistryEntry &mre = *it;
+        xml::ElementNode *pelmMachineEntry = pelmMachineRegistry->createChild("MachineEntry");
+        pelmMachineEntry->setAttribute("uuid", mre.uuid.toStringCurly());
+        pelmMachineEntry->setAttribute("src", mre.strSettingsFile);
+    }
+
+    buildMediaRegistry(*pelmGlobal, mediaRegistry);
+
+    xml::ElementNode *pelmNetServiceRegistry = pelmGlobal->createChild("NetserviceRegistry"); /** @todo r=bird: wrong capitalization of NetServiceRegistry. sigh. */
+    buildDHCPServers(*pelmNetServiceRegistry->createChild("DHCPServers"), llDhcpServers);
+
+    xml::ElementNode *pelmNATNetworks;
+    /* don't create entry if no NAT networks are registered. */
+    if (!llNATNetworks.empty())
+    {
+        pelmNATNetworks = pelmNetServiceRegistry->createChild("NATNetworks");
+        for (NATNetworksList::const_iterator it = llNATNetworks.begin();
+             it != llNATNetworks.end();
+             ++it)
+        {
+            const NATNetwork &n = *it;
+            xml::ElementNode *pelmThis = pelmNATNetworks->createChild("NATNetwork");
+            pelmThis->setAttribute("networkName", n.strNetworkName);
+            pelmThis->setAttribute("network", n.strIPv4NetworkCidr);
+            pelmThis->setAttribute("ipv6", n.fIPv6Enabled ? 1 : 0);
+            pelmThis->setAttribute("ipv6prefix", n.strIPv6Prefix);
+            pelmThis->setAttribute("advertiseDefaultIPv6Route", (n.fAdvertiseDefaultIPv6Route)? 1 : 0);
+            pelmThis->setAttribute("needDhcp", (n.fNeedDhcpServer) ? 1 : 0);
+            pelmThis->setAttribute("enabled", (n.fEnabled) ? 1 : 0);        // too bad we chose 1 vs. 0 here
+            if (n.mapPortForwardRules4.size())
+            {
+                xml::ElementNode *pelmPf4 = pelmThis->createChild("PortForwarding4");
+                buildNATForwardRulesMap(*pelmPf4, n.mapPortForwardRules4);
+            }
+            if (n.mapPortForwardRules6.size())
+            {
+                xml::ElementNode *pelmPf6 = pelmThis->createChild("PortForwarding6");
+                buildNATForwardRulesMap(*pelmPf6, n.mapPortForwardRules6);
+            }
+
+            if (n.llHostLoopbackOffsetList.size())
+            {
+                xml::ElementNode *pelmMappings = pelmThis->createChild("Mappings");
+                buildNATLoopbacks(*pelmMappings, n.llHostLoopbackOffsetList);
+
+            }
+        }
+    }
+
+#ifdef VBOX_WITH_VMNET
+    xml::ElementNode *pelmHostOnlyNetworks;
+    /* don't create entry if no HostOnly networks are registered. */
+    if (!llHostOnlyNetworks.empty())
+    {
+        pelmHostOnlyNetworks = pelmNetServiceRegistry->createChild("HostOnlyNetworks");
+        for (HostOnlyNetworksList::const_iterator it = llHostOnlyNetworks.begin();
+             it != llHostOnlyNetworks.end();
+             ++it)
+        {
+            const HostOnlyNetwork &n = *it;
+            xml::ElementNode *pelmThis = pelmHostOnlyNetworks->createChild("HostOnlyNetwork");
+            pelmThis->setAttribute("name", n.strNetworkName);
+            pelmThis->setAttribute("mask", n.strNetworkMask);
+            pelmThis->setAttribute("ipLower", n.strIPLower);
+            pelmThis->setAttribute("ipUpper", n.strIPUpper);
+            pelmThis->setAttribute("id", n.uuid.toStringCurly());
+            pelmThis->setAttribute("enabled", (n.fEnabled) ? 1 : 0);        // too bad we chose 1 vs. 0 here
+        }
+    }
+#endif /* VBOX_WITH_VMNET */
+#ifdef VBOX_WITH_CLOUD_NET
+    xml::ElementNode *pelmCloudNetworks;
+    /* don't create entry if no cloud networks are registered. */
+    if (!llCloudNetworks.empty())
+    {
+        pelmCloudNetworks = pelmNetServiceRegistry->createChild("CloudNetworks");
+        for (CloudNetworksList::const_iterator it = llCloudNetworks.begin();
+             it != llCloudNetworks.end();
+             ++it)
+        {
+            const CloudNetwork &n = *it;
+            xml::ElementNode *pelmThis = pelmCloudNetworks->createChild("CloudNetwork");
+            pelmThis->setAttribute("name", n.strNetworkName);
+            pelmThis->setAttribute("provider", n.strProviderShortName);
+            pelmThis->setAttribute("profile", n.strProfileName);
+            pelmThis->setAttribute("id", n.strNetworkId);
+            pelmThis->setAttribute("enabled", (n.fEnabled) ? 1 : 0);        // too bad we chose 1 vs. 0 here
+        }
+    }
+#endif /* VBOX_WITH_CLOUD_NET */
+
+#ifdef VBOX_WITH_UPDATE_AGENT
+    /* We keep the updates configuration as part of the host for now, as the API exposes the IHost::updateHost attribute,
+     * but use an own "Updates" branch in the XML for better structurizing stuff in the future. */
+    UpdateAgent &updateHost = host.updateHost;
+
+    xml::ElementNode *pelmUpdates = pelmGlobal->createChild("Updates");
+    /* Global enabled switch for updates. Currently bound to host updates, as this is the only update we have so far. */
+    pelmUpdates->setAttribute("enabled", updateHost.fEnabled);
+
+    xml::ElementNode *pelmUpdateHost = pelmUpdates->createChild("Host");
+    pelmUpdateHost->setAttribute("enabled", updateHost.fEnabled);
+    pelmUpdateHost->setAttribute("channel", (int32_t)updateHost.enmChannel);
+    pelmUpdateHost->setAttribute("checkFreqSec", updateHost.uCheckFreqSeconds);
+    if (updateHost.strRepoUrl.length())
+        pelmUpdateHost->setAttribute("repoUrl", updateHost.strRepoUrl);
+    if (updateHost.strLastCheckDate.length())
+        pelmUpdateHost->setAttribute("lastCheckDate", updateHost.strLastCheckDate);
+    pelmUpdateHost->setAttribute("checkCount", updateHost.uCheckCount);
+    /** @todo Add update settings for ExtPack and Guest Additions here later. See @bugref{7983}. */
+#endif
+
+    xml::ElementNode *pelmSysProps = pelmGlobal->createChild("SystemProperties");
+    if (systemProperties.strDefaultMachineFolder.length())
+        pelmSysProps->setAttribute("defaultMachineFolder", systemProperties.strDefaultMachineFolder);
+    if (systemProperties.strLoggingLevel.length())
+        pelmSysProps->setAttribute("LoggingLevel", systemProperties.strLoggingLevel);
+    if (systemProperties.strDefaultHardDiskFormat.length())
+        pelmSysProps->setAttribute("defaultHardDiskFormat", systemProperties.strDefaultHardDiskFormat);
+    if (systemProperties.strVRDEAuthLibrary.length())
+        pelmSysProps->setAttribute("VRDEAuthLibrary", systemProperties.strVRDEAuthLibrary);
+    if (systemProperties.strWebServiceAuthLibrary.length())
+        pelmSysProps->setAttribute("webServiceAuthLibrary", systemProperties.strWebServiceAuthLibrary);
+    if (systemProperties.strDefaultVRDEExtPack.length())
+        pelmSysProps->setAttribute("defaultVRDEExtPack", systemProperties.strDefaultVRDEExtPack);
+    if (systemProperties.strDefaultCryptoExtPack.length())
+        pelmSysProps->setAttribute("defaultCryptoExtPack", systemProperties.strDefaultCryptoExtPack);
+    pelmSysProps->setAttribute("LogHistoryCount", systemProperties.uLogHistoryCount);
+    if (systemProperties.strAutostartDatabasePath.length())
+        pelmSysProps->setAttribute("autostartDatabasePath", systemProperties.strAutostartDatabasePath);
+    if (systemProperties.strDefaultFrontend.length())
+        pelmSysProps->setAttribute("defaultFrontend", systemProperties.strDefaultFrontend);
+    if (systemProperties.strProxyUrl.length())
+        pelmSysProps->setAttribute("proxyUrl", systemProperties.strProxyUrl);
+    pelmSysProps->setAttribute("proxyMode", systemProperties.uProxyMode);
+    pelmSysProps->setAttribute("exclusiveHwVirt", systemProperties.fExclusiveHwVirt);
+    if (systemProperties.strLanguageId.isNotEmpty())
+        pelmSysProps->setAttribute("LanguageId", systemProperties.strLanguageId);
+
+    buildUSBDeviceFilters(*pelmGlobal->createChild("USBDeviceFilters"),
+                          host.llUSBDeviceFilters,
+                          true);               // fHostMode
+
+    if (!host.llUSBDeviceSources.empty())
+        buildUSBDeviceSources(*pelmGlobal->createChild("USBDeviceSources"),
+                              host.llUSBDeviceSources);
+
+    // now go write the XML
+    xml::XmlFileWriter writer(*m->pDoc);
+    writer.write(m->strFilename.c_str(), true /*fSafe*/);
+
+    m->fFileExists = true;
+
+    clearDocument();
+    LogRel(("Finished saving settings file \"%s\"\n", m->strFilename.c_str()));
+}
+
+////////////////////////////////////////////////////////////////////////////////
+//
+// Machine XML structures
+//
+////////////////////////////////////////////////////////////////////////////////
+
+/**
+ * Constructor. Needs to set sane defaults which stand the test of time.
+ */
+VRDESettings::VRDESettings() :
+    fEnabled(true), // default for old VMs, for new ones it's false
+    authType(AuthType_Null),
+    ulAuthTimeout(5000),
+    fAllowMultiConnection(false),
+    fReuseSingleConnection(false)
+{
+}
+
+/**
+ * Check if all settings have default values.
+ */
+bool VRDESettings::areDefaultSettings(SettingsVersion_T sv) const
+{
+    return (sv < SettingsVersion_v1_16 ? fEnabled : !fEnabled)
+        && authType == AuthType_Null
+        && (ulAuthTimeout == 5000 || ulAuthTimeout == 0)
+        && strAuthLibrary.isEmpty()
+        && !fAllowMultiConnection
+        && !fReuseSingleConnection
+        && strVrdeExtPack.isEmpty()
+        && mapProperties.size() == 0;
+}
+
+/**
+ * Comparison operator. This gets called from MachineConfigFile::operator==,
+ * which in turn gets called from Machine::saveSettings to figure out whether
+ * machine settings have really changed and thus need to be written out to disk.
+ */
+bool VRDESettings::operator==(const VRDESettings& v) const
+{
+    return (this == &v)
+        || (   fEnabled                  == v.fEnabled
+            && authType                  == v.authType
+            && ulAuthTimeout             == v.ulAuthTimeout
+            && strAuthLibrary            == v.strAuthLibrary
+            && fAllowMultiConnection     == v.fAllowMultiConnection
+            && fReuseSingleConnection    == v.fReuseSingleConnection
+            && strVrdeExtPack            == v.strVrdeExtPack
+            && mapProperties             == v.mapProperties);
+}
+
+/**
+ * Constructor. Needs to set sane defaults which stand the test of time.
+ */
+BIOSSettings::BIOSSettings() :
+    fACPIEnabled(true),
+    fIOAPICEnabled(false),
+    fLogoFadeIn(true),
+    fLogoFadeOut(true),
+    fPXEDebugEnabled(false),
+    fSmbiosUuidLittleEndian(true),
+    ulLogoDisplayTime(0),
+    biosBootMenuMode(BIOSBootMenuMode_MessageAndMenu),
+    apicMode(APICMode_APIC),
+    llTimeOffset(0)
+{
+}
+
+/**
+ * Check if all settings have default values.
+ */
+bool BIOSSettings::areDefaultSettings() const
+{
+    return fACPIEnabled
+        && !fIOAPICEnabled
+        && fLogoFadeIn
+        && fLogoFadeOut
+        && !fPXEDebugEnabled
+        && !fSmbiosUuidLittleEndian
+        && ulLogoDisplayTime == 0
+        && biosBootMenuMode == BIOSBootMenuMode_MessageAndMenu
+        && apicMode == APICMode_APIC
+        && llTimeOffset == 0
+        && strLogoImagePath.isEmpty();
+}
+
+/**
+ * Comparison operator. This gets called from MachineConfigFile::operator==,
+ * which in turn gets called from Machine::saveSettings to figure out whether
+ * machine settings have really changed and thus need to be written out to disk.
+ */
+bool BIOSSettings::operator==(const BIOSSettings &d) const
+{
+    return (this == &d)
+        || (   fACPIEnabled            == d.fACPIEnabled
+            && fIOAPICEnabled          == d.fIOAPICEnabled
+            && fLogoFadeIn             == d.fLogoFadeIn
+            && fLogoFadeOut            == d.fLogoFadeOut
+            && fPXEDebugEnabled        == d.fPXEDebugEnabled
+            && fSmbiosUuidLittleEndian == d.fSmbiosUuidLittleEndian
+            && ulLogoDisplayTime       == d.ulLogoDisplayTime
+            && biosBootMenuMode        == d.biosBootMenuMode
+            && apicMode                == d.apicMode
+            && llTimeOffset            == d.llTimeOffset
+            && strLogoImagePath        == d.strLogoImagePath);
+}
+
+RecordingScreenSettings::RecordingScreenSettings(uint32_t a_idScreen /* = UINT32_MAX */)
+    : idScreen(a_idScreen)
+{
+    applyDefaults();
+}
+
+RecordingScreenSettings::~RecordingScreenSettings()
+{
+
+}
+
+/**
+ * Returns the default options string for screen recording settings.
+ *
+ * @returns Default options string for a given screen.
+ */
+/* static */
+const char *RecordingScreenSettings::getDefaultOptions(void)
+{
+    /* Note: Needs to be kept in sync with FE/Qt's UIMachineSettingsDisplay::putToCache()! */
+    return "vc_enabled=true,ac_enabled=false,ac_profile=med";
+}
+
+/**
+ * Returns a recording settings feature map from a given string.
+ *
+ * @returns VBox status code.
+ * @param   strFeatures         String of features to convert.
+ * @param   featureMap          Where to return the converted features on success.
+ */
+/* static */
+int RecordingScreenSettings::featuresFromString(const com::Utf8Str &strFeatures, RecordingFeatureMap &featureMap)
+{
+    featureMap.clear();
+
+    RTCList<RTCString> lstFeatures = strFeatures.split(" ");
+    for (size_t i = 0; i < lstFeatures.size(); i++)
+    {
+        if (lstFeatures.at(i).compare("video", RTCString::CaseInsensitive) == 0)
+            featureMap[RecordingFeature_Video] = true;
+        else if (lstFeatures.at(i).compare("audio", RTCString::CaseInsensitive) == 0)
+            featureMap[RecordingFeature_Audio] = true;
+        /* ignore everything else */
+    }
+
+    return VINF_SUCCESS;
+}
+
+/**
+ * Converts a feature map to a serializable string.
+ *
+ * @param   featureMap          Feature map to convert.
+ * @param   strFeatures         Where to return the features converted as a string.
+ */
+/* static */
+void RecordingScreenSettings::featuresToString(const RecordingFeatureMap &featureMap, com::Utf8Str &strFeatures)
+{
+    strFeatures = "";
+
+    RecordingFeatureMap::const_iterator itFeature = featureMap.begin();
+    while (itFeature != featureMap.end())
+    {
+        if (itFeature->first == RecordingFeature_Video && itFeature->second)
+            strFeatures += "video ";
+        if (itFeature->first == RecordingFeature_Audio && itFeature->second)
+            strFeatures += "audio ";
+        ++itFeature;
+    }
+    strFeatures.strip();
+}
+
+/**
+ * Returns a recording settings audio codec from a given string.
+ *
+ * @returns VBox status code.
+ * @retval  VERR_NOT_SUPPORTED if audio codec is invalid or not supported.
+ * @param   strCodec            String that contains the codec name.
+ * @param   enmCodec            Where to return the audio codec on success.
+ *
+ * @note    An empty string will return "none" (no codec).
+ */
+/* static */
+int RecordingScreenSettings::audioCodecFromString(const com::Utf8Str &strCodec, RecordingAudioCodec_T &enmCodec)
+{
+    if (   RTStrIStr(strCodec.c_str(), "none")
+        || strCodec.isEmpty())
+    {
+        enmCodec = RecordingAudioCodec_None;
+        return VINF_SUCCESS;
+    }
+    else if (RTStrIStr(strCodec.c_str(), "wav"))
+    {
+        enmCodec = RecordingAudioCodec_WavPCM;
+        return VINF_SUCCESS;
+    }
+    else if (RTStrIStr(strCodec.c_str(), "mp3"))
+    {
+        enmCodec = RecordingAudioCodec_MP3;
+        return VINF_SUCCESS;
+    }
+    else if (RTStrIStr(strCodec.c_str(), "opus"))
+    {
+        enmCodec = RecordingAudioCodec_Opus;
+        return VINF_SUCCESS;
+    }
+    else if (RTStrIStr(strCodec.c_str(), "vorbis"))
+    {
+        enmCodec = RecordingAudioCodec_OggVorbis;
+        return VINF_SUCCESS;
+    }
+
+    AssertFailedReturn(VERR_NOT_SUPPORTED);
+}
+
+/**
+ * Converts an audio codec to a serializable string.
+ *
+ * @param   enmCodec            Codec to convert to a string.
+ * @param   strCodec            Where to return the audio codec converted as a string.
+ */
+/* static */
+void RecordingScreenSettings::audioCodecToString(const RecordingAudioCodec_T &enmCodec, com::Utf8Str &strCodec)
+{
+    switch (enmCodec)
+    {
+        case RecordingAudioCodec_None:      strCodec = "none";   return;
+        case RecordingAudioCodec_WavPCM:    strCodec = "wav";    return;
+        case RecordingAudioCodec_MP3:       strCodec = "mp3";    return;
+        case RecordingAudioCodec_Opus:      strCodec = "opus";   return;
+        case RecordingAudioCodec_OggVorbis: strCodec = "vorbis"; return;
+        default:                            AssertFailedReturnVoid();
+    }
+}
+
+/**
+ * Returns a recording settings video codec from a given string.
+ *
+ * @returns VBox status code.
+ * @retval  VERR_NOT_SUPPORTED if video codec is invalid or not supported.
+ * @param   strCodec            String that contains the codec name.
+ * @param   enmCodec            Where to return the video codec on success.
+ *
+ * @note    An empty string will return "none" (no codec).
+ */
+/* static */
+int RecordingScreenSettings::videoCodecFromString(const com::Utf8Str &strCodec, RecordingVideoCodec_T &enmCodec)
+{
+    if (   RTStrIStr(strCodec.c_str(), "none")
+        || strCodec.isEmpty())
+    {
+        enmCodec = RecordingVideoCodec_None;
+        return VINF_SUCCESS;
+    }
+    else if (RTStrIStr(strCodec.c_str(), "MJPEG"))
+    {
+        enmCodec = RecordingVideoCodec_MJPEG;
+        return VINF_SUCCESS;
+    }
+    else if (RTStrIStr(strCodec.c_str(), "H262"))
+    {
+        enmCodec = RecordingVideoCodec_H262;
+        return VINF_SUCCESS;
+    }
+    else if (RTStrIStr(strCodec.c_str(), "H264"))
+    {
+        enmCodec = RecordingVideoCodec_H264;
+        return VINF_SUCCESS;
+    }
+    else if (RTStrIStr(strCodec.c_str(), "H265"))
+    {
+        enmCodec = RecordingVideoCodec_H265;
+        return VINF_SUCCESS;
+    }
+    else if (RTStrIStr(strCodec.c_str(), "H266"))
+    {
+        enmCodec = RecordingVideoCodec_H266;
+        return VINF_SUCCESS;
+    }
+    else if (RTStrIStr(strCodec.c_str(), "VP8"))
+    {
+        enmCodec = RecordingVideoCodec_VP8;
+        return VINF_SUCCESS;
+    }
+    else if (RTStrIStr(strCodec.c_str(), "VP9"))
+    {
+        enmCodec = RecordingVideoCodec_VP9;
+        return VINF_SUCCESS;
+    }
+    else if (RTStrIStr(strCodec.c_str(), "AV1"))
+    {
+        enmCodec = RecordingVideoCodec_AV1;
+        return VINF_SUCCESS;
+    }
+    else if (RTStrIStr(strCodec.c_str(), "other"))
+    {
+        enmCodec = RecordingVideoCodec_Other;
+        return VINF_SUCCESS;
+    }
+
+    AssertFailedReturn(VERR_NOT_SUPPORTED);
+}
+
+/**
+ * Converts a video codec to a serializable string.
+ *
+ * @param   enmCodec            Codec to convert to a string.
+ * @param   strCodec            Where to return the video codec converted as a string.
+ */
+/* static */
+void RecordingScreenSettings::videoCodecToString(const RecordingVideoCodec_T &enmCodec, com::Utf8Str &strCodec)
+{
+    switch (enmCodec)
+    {
+        case RecordingVideoCodec_None:  strCodec = "none";  return;
+        case RecordingVideoCodec_MJPEG: strCodec = "MJPEG"; return;
+        case RecordingVideoCodec_H262:  strCodec = "H262";  return;
+        case RecordingVideoCodec_H264:  strCodec = "H264";  return;
+        case RecordingVideoCodec_H265:  strCodec = "H265";  return;
+        case RecordingVideoCodec_H266:  strCodec = "H266";  return;
+        case RecordingVideoCodec_VP8:   strCodec = "VP8";   return;
+        case RecordingVideoCodec_VP9:   strCodec = "VP9";   return;
+        case RecordingVideoCodec_AV1:   strCodec = "AV1";   return;
+        case RecordingVideoCodec_Other: strCodec = "other"; return;
+        default:                        AssertFailedReturnVoid();
+    }
+}
+
+/**
+ * Applies the default settings.
+ */
+void RecordingScreenSettings::applyDefaults(void)
+{
+    /*
+     * Set sensible defaults.
+     */
+
+    /*
+     * Enable screen 0 by default.
+     * Otherwise enabling recording without any screen enabled at all makes no sense.
+     *
+     * Note: When tweaking this, make sure to also alter RecordingScreenSettings::areDefaultSettings().
+     */
+    fEnabled             = idScreen == 0 ? true : false;;
+    enmDest              = RecordingDestination_File;
+    ulMaxTimeS           = 0;
+    strOptions           = RecordingScreenSettings::getDefaultOptions();
+    File.ulMaxSizeMB     = 0;
+    File.strName         = "";
+    Video.enmCodec       = RecordingVideoCodec_VP8;
+    Video.enmDeadline    = RecordingCodecDeadline_Default;
+    Video.enmRateCtlMode = RecordingRateControlMode_VBR;
+    Video.enmScalingMode = RecordingVideoScalingMode_None;
+    Video.ulWidth        = 1024;
+    Video.ulHeight       = 768;
+    Video.ulRate         = 512;
+    Video.ulFPS          = 25;
+#ifdef VBOX_WITH_AUDIO_RECORDING
+# if   defined(VBOX_WITH_LIBVORBIS)
+    Audio.enmCodec       = RecordingAudioCodec_OggVorbis;
+# else
+    Audio.enmCodec       = RecordingAudioCodec_None;
+# endif
+#else
+    Audio.enmCodec       = RecordingAudioCodec_None;
+#endif /* VBOX_WITH_RECORDING */
+    Audio.enmDeadline    = RecordingCodecDeadline_Default;
+    Audio.enmRateCtlMode = RecordingRateControlMode_VBR;
+    Audio.cBits          = 16;
+    Audio.cChannels      = 2;
+    Audio.uHz            = 22050;
+
+    featureMap[RecordingFeature_Video] = true;
+    featureMap[RecordingFeature_Audio] = false; /** @todo Audio is not yet enabled by default. */
+}
+
+/**
+ * Check if all settings have default values.
+ *
+ * @returns @c true if default, @c false if not.
+ */
+bool RecordingScreenSettings::areDefaultSettings(void) const
+{
+    return    (   fEnabled                                    == false
+               /* Screen 0 is special: There we ALWAYS enable recording by default. */
+               || (   idScreen                                == 0
+                   && fEnabled                                == true)
+              )
+           && enmDest                                         == RecordingDestination_File
+           && ulMaxTimeS                                      == 0
+           && strOptions                                      == RecordingScreenSettings::getDefaultOptions()
+           && File.ulMaxSizeMB                                == 0
+           && File.strName                                    == ""
+           && Video.enmCodec                                  == RecordingVideoCodec_VP8
+           && Video.enmDeadline                               == RecordingCodecDeadline_Default
+           && Video.enmRateCtlMode                            == RecordingRateControlMode_VBR
+           && Video.enmScalingMode                            == RecordingVideoScalingMode_None
+           && Video.ulWidth                                   == 1024
+           && Video.ulHeight                                  == 768
+           && Video.ulRate                                    == 512
+           && Video.ulFPS                                     == 25
+#ifdef VBOX_WITH_AUDIO_RECORDING
+# if   defined(VBOX_WITH_LIBVORBIS)
+           && Audio.enmCodec                                  == RecordingAudioCodec_OggVorbis
+# else
+           && Audio.enmCodec                                  == RecordingAudioCodec_None
+# endif
+#else
+           && Audio.enmCodec                                  == RecordingAudioCodec_None
+#endif /* VBOX_WITH_AUDIO_RECORDING */
+           && Audio.enmDeadline                               == RecordingCodecDeadline_Default
+           && Audio.enmRateCtlMode                            == RecordingRateControlMode_VBR
+           && Audio.cBits                                     == 16
+           && Audio.cChannels                                 == 2
+           && Audio.uHz                                       == 22050
+           && featureMap.find(RecordingFeature_Video)->second == true
+           && featureMap.find(RecordingFeature_Audio)->second == false;
+}
+
+/**
+ * Returns if a certain recording feature is enabled or not.
+ *
+ * @returns @c true if the feature is enabled, @c false if not.
+ * @param   enmFeature          Feature to check.
+ */
+bool RecordingScreenSettings::isFeatureEnabled(RecordingFeature_T enmFeature) const
+{
+    RecordingFeatureMap::const_iterator itFeature = featureMap.find(enmFeature);
+    if (itFeature != featureMap.end())
+        return itFeature->second;
+
+    return false;
+}
+
+/**
+ * Comparison operator. This gets called from MachineConfigFile::operator==,
+ * which in turn gets called from Machine::saveSettings to figure out whether
+ * machine settings have really changed and thus need to be written out to disk.
+ */
+bool RecordingScreenSettings::operator==(const RecordingScreenSettings &d) const
+{
+    return    fEnabled             == d.fEnabled
+           && enmDest              == d.enmDest
+           && featureMap           == d.featureMap
+           && ulMaxTimeS           == d.ulMaxTimeS
+           && strOptions           == d.strOptions
+           && File.strName         == d.File.strName
+           && File.ulMaxSizeMB     == d.File.ulMaxSizeMB
+           && Video.enmCodec       == d.Video.enmCodec
+           && Video.enmDeadline    == d.Video.enmDeadline
+           && Video.enmRateCtlMode == d.Video.enmRateCtlMode
+           && Video.enmScalingMode == d.Video.enmScalingMode
+           && Video.ulWidth        == d.Video.ulWidth
+           && Video.ulHeight       == d.Video.ulHeight
+           && Video.ulRate         == d.Video.ulRate
+           && Video.ulFPS          == d.Video.ulFPS
+           && Audio.enmCodec       == d.Audio.enmCodec
+           && Audio.enmDeadline    == d.Audio.enmDeadline
+           && Audio.enmRateCtlMode == d.Audio.enmRateCtlMode
+           && Audio.cBits          == d.Audio.cBits
+           && Audio.cChannels      == d.Audio.cChannels
+           && Audio.uHz            == d.Audio.uHz
+           && featureMap           == d.featureMap;
+}
+
+/**
+ * Constructor. Needs to set sane defaults which stand the test of time.
+ */
+RecordingCommonSettings::RecordingCommonSettings()
+{
+    applyDefaults();
+}
+
+/**
+ * Applies the default settings.
+ */
+void RecordingCommonSettings::applyDefaults(void)
+{
+    fEnabled = false;
+}
+
+/**
+ * Check if all settings have default values.
+ */
+bool RecordingCommonSettings::areDefaultSettings(void) const
+{
+    return fEnabled == false;
+}
+
+/**
+ * Comparison operator. This gets called from MachineConfigFile::operator==,
+ * which in turn gets called from Machine::saveSettings to figure out whether
+ * machine settings have really changed and thus need to be written out to disk.
+ */
+bool RecordingCommonSettings::operator==(const RecordingCommonSettings &d) const
+{
+    if (this == &d)
+        return true;
+
+    return fEnabled == d.fEnabled;
+}
+
+/**
+ * Constructor. Needs to set sane defaults which stand the test of time.
+ */
+RecordingSettings::RecordingSettings()
+{
+    applyDefaults();
+}
+
+/**
+ * Applies the default settings.
+ */
+void RecordingSettings::applyDefaults(void)
+{
+    common.applyDefaults();
+
+    mapScreens.clear();
+
+    try
+    {
+        /* Always add screen 0 to the default configuration. */
+        RecordingScreenSettings screenSettings(0 /* Screen ID */);
+
+        mapScreens[0 /* Screen ID */] = screenSettings;
+    }
+    catch (std::bad_alloc &)
+    {
+        AssertFailed();
+    }
+}
+
+/**
+ * Check if all settings have default values.
+ */
+bool RecordingSettings::areDefaultSettings(void) const
+{
+    AssertReturn(mapScreens.size() >= 1, false); /* The first screen always must be present. */
+
+    if (!common.areDefaultSettings())
+        return false;
+
+    RecordingScreenSettingsMap::const_iterator itScreen = mapScreens.begin();
+    while (itScreen != mapScreens.end())
+    {
+        if (!itScreen->second.areDefaultSettings())
+            return false;
+        ++itScreen;
+    }
+
+    return true;
+}
+
+/**
+ * Comparison operator. This gets called from MachineConfigFile::operator==,
+ * which in turn gets called from Machine::saveSettings to figure out whether
+ * machine settings have really changed and thus need to be written out to disk.
+ */
+bool RecordingSettings::operator==(const RecordingSettings &that) const
+{
+    if (this == &that) /* If pointers match, take a shortcut. */
+        return true;
+
+    if (common == that.common)
+    {
+        /* Too lazy for a != operator. */
+    }
+    else
+        return false;
+
+    if (mapScreens.size() != that.mapScreens.size())
+        return false;
+
+    RecordingScreenSettingsMap::const_iterator itScreen     = mapScreens.begin();
+    RecordingScreenSettingsMap::const_iterator itScreenThat = that.mapScreens.begin();
+    while (   itScreen     != mapScreens.end()
+           && itScreenThat != that.mapScreens.end())
+    {
+        if (itScreen->second == itScreenThat->second)
+        {
+            /* Nothing to do in here (yet). */
+        }
+        else
+            return false;
+
+        ++itScreen;
+        ++itScreenThat;
+    }
+
+    return true;
+}
+
+/**
+ * Constructor. Needs to set sane defaults which stand the test of time.
+ */
+GraphicsAdapter::GraphicsAdapter() :
+    graphicsControllerType(GraphicsControllerType_VBoxVGA),
+    ulVRAMSizeMB(8),
+    cMonitors(1),
+    fAccelerate3D(false),
+    fAccelerate2DVideo(false)
+{
+}
+
+/**
+ * Check if all settings have default values.
+ */
+bool GraphicsAdapter::areDefaultSettings() const
+{
+    return graphicsControllerType == GraphicsControllerType_VBoxVGA
+        && ulVRAMSizeMB == 8
+        && cMonitors <= 1
+        && !fAccelerate3D
+        && !fAccelerate2DVideo;
+}
+
+/**
+ * Comparison operator. This gets called from MachineConfigFile::operator==,
+ * which in turn gets called from Machine::saveSettings to figure out whether
+ * machine settings have really changed and thus need to be written out to disk.
+ */
+bool GraphicsAdapter::operator==(const GraphicsAdapter &g) const
+{
+    return (this == &g)
+        || (   graphicsControllerType         == g.graphicsControllerType
+            && ulVRAMSizeMB                   == g.ulVRAMSizeMB
+            && cMonitors                      == g.cMonitors
+            && fAccelerate3D                  == g.fAccelerate3D
+            && fAccelerate2DVideo             == g.fAccelerate2DVideo);
+}
+
+/**
+ * Constructor. Needs to set sane defaults which stand the test of time.
+ */
+TpmSettings::TpmSettings() :
+    tpmType(TpmType_None)
+{
+}
+
+/**
+ * Check if all settings have default values.
+ */
+bool TpmSettings::areDefaultSettings() const
+{
+    return    tpmType     == TpmType_None
+           && strLocation.isEmpty();
+}
+
+/**
+ * Comparison operator. This gets called from MachineConfigFile::operator==,
+ * which in turn gets called from Machine::saveSettings to figure out whether
+ * machine settings have really changed and thus need to be written out to disk.
+ */
+bool TpmSettings::operator==(const TpmSettings &g) const
+{
+    return (this == &g)
+        || (   tpmType         == g.tpmType
+            && strLocation     == g.strLocation);
+}
+
+/**
+ * Constructor. Needs to set sane defaults which stand the test of time.
+ */
+NvramSettings::NvramSettings()
+{
+}
+
+/**
+ * Check if all settings have default values.
+ */
+bool NvramSettings::areDefaultSettings() const
+{
+    return     strNvramPath.isEmpty()
+            && strKeyId.isEmpty()
+            && strKeyStore.isEmpty();
+}
+
+/**
+ * Comparison operator. This gets called from MachineConfigFile::operator==,
+ * which in turn gets called from Machine::saveSettings to figure out whether
+ * machine settings have really changed and thus need to be written out to disk.
+ */
+bool NvramSettings::operator==(const NvramSettings &g) const
+{
+    return (this == &g)
+        || (strNvramPath    == g.strNvramPath)
+        || (strKeyId        == g.strKeyId)
+        || (strKeyStore     == g.strKeyStore);
+}
+
+
+/**
+ * Constructor. Needs to set sane defaults which stand the test of time.
+ */
+USBController::USBController() :
+    enmType(USBControllerType_Null)
+{
+}
+
+/**
+ * Comparison operator. This gets called from MachineConfigFile::operator==,
+ * which in turn gets called from Machine::saveSettings to figure out whether
+ * machine settings have really changed and thus need to be written out to disk.
+ */
+bool USBController::operator==(const USBController &u) const
+{
+    return (this == &u)
+        || (   strName == u.strName
+            && enmType == u.enmType);
+}
+
+/**
+ * Constructor. Needs to set sane defaults which stand the test of time.
+ */
+USB::USB()
+{
+}
+
+/**
+ * Comparison operator. This gets called from MachineConfigFile::operator==,
+ * which in turn gets called from Machine::saveSettings to figure out whether
+ * machine settings have really changed and thus need to be written out to disk.
+ */
+bool USB::operator==(const USB &u) const
+{
+    return (this == &u)
+        || (   llUSBControllers == u.llUSBControllers
+            && llDeviceFilters  == u.llDeviceFilters);
+}
+
+/**
+ * Constructor. Needs to set sane defaults which stand the test of time.
+ */
+NAT::NAT() :
+    u32Mtu(0),
+    u32SockRcv(0),
+    u32SockSnd(0),
+    u32TcpRcv(0),
+    u32TcpSnd(0),
+    fDNSPassDomain(true), /* historically this value is true */
+    fDNSProxy(false),
+    fDNSUseHostResolver(false),
+    fAliasLog(false),
+    fAliasProxyOnly(false),
+    fAliasUseSamePorts(false),
+    fLocalhostReachable(true) /* Historically this value is true. */
+{
+}
+
+/**
+ * Check if all DNS settings have default values.
+ */
+bool NAT::areDNSDefaultSettings() const
+{
+    return fDNSPassDomain && !fDNSProxy && !fDNSUseHostResolver;
+}
+
+/**
+ * Check if all Alias settings have default values.
+ */
+bool NAT::areAliasDefaultSettings() const
+{
+    return !fAliasLog && !fAliasProxyOnly && !fAliasUseSamePorts;
+}
+
+/**
+ * Check if all TFTP settings have default values.
+ */
+bool NAT::areTFTPDefaultSettings() const
+{
+    return strTFTPPrefix.isEmpty()
+        && strTFTPBootFile.isEmpty()
+        && strTFTPNextServer.isEmpty();
+}
+
+/**
+ * Check whether the localhost-reachable setting is the default for the given settings version.
+ */
+bool NAT::areLocalhostReachableDefaultSettings(SettingsVersion_T sv) const
+{
+    return    (   fLocalhostReachable
+                && sv < SettingsVersion_v1_19)
+           || (   !fLocalhostReachable
+                && sv >= SettingsVersion_v1_19);
+}
+
+/**
+ * Check if all settings have default values.
+ */
+bool NAT::areDefaultSettings(SettingsVersion_T sv) const
+{
+    /*
+     * Before settings version 1.19 localhost was reachable by default
+     * when using NAT which was changed with version 1.19+, see @bugref{9896}
+     * for more information.
+     */
+    return strNetwork.isEmpty()
+        && strBindIP.isEmpty()
+        && u32Mtu == 0
+        && u32SockRcv == 0
+        && u32SockSnd == 0
+        && u32TcpRcv == 0
+        && u32TcpSnd == 0
+        && areDNSDefaultSettings()
+        && areAliasDefaultSettings()
+        && areTFTPDefaultSettings()
+        && mapRules.size() == 0
+        && areLocalhostReachableDefaultSettings(sv);
+}
+
+/**
+ * Comparison operator. This gets called from MachineConfigFile::operator==,
+ * which in turn gets called from Machine::saveSettings to figure out whether
+ * machine settings have really changed and thus need to be written out to disk.
+ */
+bool NAT::operator==(const NAT &n) const
+{
+   return (this == &n)
+       || (   strNetwork           == n.strNetwork
+            && strBindIP           == n.strBindIP
+            && u32Mtu              == n.u32Mtu
+            && u32SockRcv          == n.u32SockRcv
+            && u32SockSnd          == n.u32SockSnd
+            && u32TcpSnd           == n.u32TcpSnd
+            && u32TcpRcv           == n.u32TcpRcv
+            && strTFTPPrefix       == n.strTFTPPrefix
+            && strTFTPBootFile     == n.strTFTPBootFile
+            && strTFTPNextServer   == n.strTFTPNextServer
+            && fDNSPassDomain      == n.fDNSPassDomain
+            && fDNSProxy           == n.fDNSProxy
+            && fDNSUseHostResolver == n.fDNSUseHostResolver
+            && fAliasLog           == n.fAliasLog
+            && fAliasProxyOnly     == n.fAliasProxyOnly
+            && fAliasUseSamePorts  == n.fAliasUseSamePorts
+            && fLocalhostReachable == n.fLocalhostReachable
+            && mapRules            == n.mapRules);
+}
+
+/**
+ * Constructor. Needs to set sane defaults which stand the test of time.
+ */
+NetworkAdapter::NetworkAdapter() :
+    ulSlot(0),
+    type(NetworkAdapterType_Am79C970A), // default for old VMs, for new ones it's Am79C973
+    fEnabled(false),
+    fCableConnected(false), // default for old VMs, for new ones it's true
+    ulLineSpeed(0),
+    enmPromiscModePolicy(NetworkAdapterPromiscModePolicy_Deny),
+    fTraceEnabled(false),
+    mode(NetworkAttachmentType_Null),
+    ulBootPriority(0)
+{
+}
+
+/**
+ * Check if all Generic Driver settings have default values.
+ */
+bool NetworkAdapter::areGenericDriverDefaultSettings() const
+{
+    return strGenericDriver.isEmpty()
+        && genericProperties.size() == 0;
+}
+
+/**
+ * Check if all settings have default values.
+ */
+bool NetworkAdapter::areDefaultSettings(SettingsVersion_T sv) const
+{
+    // 5.0 and earlier had a default of fCableConnected=false, which doesn't
+    // make a lot of sense (but it's a fact). Later versions don't save the
+    // setting if it's at the default value and thus must get it right.
+    return !fEnabled
+        && strMACAddress.isEmpty()
+        && (   (sv >= SettingsVersion_v1_16 && fCableConnected && type == NetworkAdapterType_Am79C973)
+            || (sv < SettingsVersion_v1_16 && !fCableConnected && type == NetworkAdapterType_Am79C970A))
+        && ulLineSpeed == 0
+        && enmPromiscModePolicy == NetworkAdapterPromiscModePolicy_Deny
+        && mode == NetworkAttachmentType_Null
+        && nat.areDefaultSettings(sv)
+        && strBridgedName.isEmpty()
+        && strInternalNetworkName.isEmpty()
+#ifdef VBOX_WITH_VMNET
+        && strHostOnlyNetworkName.isEmpty()
+#endif /* VBOX_WITH_VMNET */
+#ifdef VBOX_WITH_CLOUD_NET
+        && strCloudNetworkName.isEmpty()
+#endif /* VBOX_WITH_CLOUD_NET */
+        && strHostOnlyName.isEmpty()
+        && areGenericDriverDefaultSettings()
+        && strNATNetworkName.isEmpty();
+}
+
+/**
+ * Special check if settings of the non-current attachment type have default values.
+ */
+bool NetworkAdapter::areDisabledDefaultSettings(SettingsVersion_T sv) const
+{
+    return (mode != NetworkAttachmentType_NAT ? nat.areDefaultSettings(sv) : true)
+        && (mode != NetworkAttachmentType_Bridged ? strBridgedName.isEmpty() : true)
+        && (mode != NetworkAttachmentType_Internal ? strInternalNetworkName.isEmpty() : true)
+#ifdef VBOX_WITH_VMNET
+        && (mode != NetworkAttachmentType_HostOnlyNetwork ? strHostOnlyNetworkName.isEmpty() : true)
+#endif /* VBOX_WITH_VMNET */
+#ifdef VBOX_WITH_CLOUD_NET
+        && (mode != NetworkAttachmentType_Cloud ? strCloudNetworkName.isEmpty() : true)
+#endif /* VBOX_WITH_CLOUD_NET */
+        && (mode != NetworkAttachmentType_HostOnly ? strHostOnlyName.isEmpty() : true)
+        && (mode != NetworkAttachmentType_Generic ? areGenericDriverDefaultSettings() : true)
+        && (mode != NetworkAttachmentType_NATNetwork ? strNATNetworkName.isEmpty() : true);
+}
+
+/**
+ * Comparison operator. This gets called from MachineConfigFile::operator==,
+ * which in turn gets called from Machine::saveSettings to figure out whether
+ * machine settings have really changed and thus need to be written out to disk.
+ */
+bool NetworkAdapter::operator==(const NetworkAdapter &n) const
+{
+    return (this == &n)
+        || (   ulSlot                == n.ulSlot
+            && type                  == n.type
+            && fEnabled              == n.fEnabled
+            && strMACAddress         == n.strMACAddress
+            && fCableConnected       == n.fCableConnected
+            && ulLineSpeed           == n.ulLineSpeed
+            && enmPromiscModePolicy  == n.enmPromiscModePolicy
+            && fTraceEnabled         == n.fTraceEnabled
+            && strTraceFile          == n.strTraceFile
+            && mode                  == n.mode
+            && nat                   == n.nat
+            && strBridgedName        == n.strBridgedName
+            && strHostOnlyName       == n.strHostOnlyName
+#ifdef VBOX_WITH_VMNET
+            && strHostOnlyNetworkName == n.strHostOnlyNetworkName
+#endif /* VBOX_WITH_VMNET */
+            && strInternalNetworkName == n.strInternalNetworkName
+#ifdef VBOX_WITH_CLOUD_NET
+            && strCloudNetworkName   == n.strCloudNetworkName
+#endif /* VBOX_WITH_CLOUD_NET */
+            && strGenericDriver      == n.strGenericDriver
+            && genericProperties     == n.genericProperties
+            && ulBootPriority        == n.ulBootPriority
+            && strBandwidthGroup     == n.strBandwidthGroup);
+}
+
+/**
+ * Constructor. Needs to set sane defaults which stand the test of time.
+ */
+SerialPort::SerialPort() :
+    ulSlot(0),
+    fEnabled(false),
+    ulIOBase(0x3f8),
+    ulIRQ(4),
+    portMode(PortMode_Disconnected),
+    fServer(false),
+    uartType(UartType_U16550A)
+{
+}
+
+/**
+ * Comparison operator. This gets called from MachineConfigFile::operator==,
+ * which in turn gets called from Machine::saveSettings to figure out whether
+ * machine settings have really changed and thus need to be written out to disk.
+ */
+bool SerialPort::operator==(const SerialPort &s) const
+{
+    return (this == &s)
+        || (   ulSlot            == s.ulSlot
+            && fEnabled          == s.fEnabled
+            && ulIOBase          == s.ulIOBase
+            && ulIRQ             == s.ulIRQ
+            && portMode          == s.portMode
+            && strPath           == s.strPath
+            && fServer           == s.fServer
+            && uartType          == s.uartType);
+}
+
+/**
+ * Constructor. Needs to set sane defaults which stand the test of time.
+ */
+ParallelPort::ParallelPort() :
+    ulSlot(0),
+    fEnabled(false),
+    ulIOBase(0x378),
+    ulIRQ(7)
+{
+}
+
+/**
+ * Comparison operator. This gets called from MachineConfigFile::operator==,
+ * which in turn gets called from Machine::saveSettings to figure out whether
+ * machine settings have really changed and thus need to be written out to disk.
+ */
+bool ParallelPort::operator==(const ParallelPort &s) const
+{
+    return (this == &s)
+        || (   ulSlot            == s.ulSlot
+            && fEnabled          == s.fEnabled
+            && ulIOBase          == s.ulIOBase
+            && ulIRQ             == s.ulIRQ
+            && strPath           == s.strPath);
+}
+
+/**
+ * Constructor. Needs to set sane defaults which stand the test of time.
+ */
+AudioAdapter::AudioAdapter() :
+    fEnabled(true), // default for old VMs, for new ones it's false
+    fEnabledIn(true), // default for old VMs, for new ones it's false
+    fEnabledOut(true), // default for old VMs, for new ones it's false
+    controllerType(AudioControllerType_AC97),
+    codecType(AudioCodecType_STAC9700),
+    driverType(AudioDriverType_Null)
+{
+}
+
+/**
+ * Check if all settings have default values.
+ */
+bool AudioAdapter::areDefaultSettings(SettingsVersion_T sv) const
+{
+    return (sv < SettingsVersion_v1_16 ? false : !fEnabled)
+        && (sv <= SettingsVersion_v1_16 ? fEnabledIn : !fEnabledIn)
+        && (sv <= SettingsVersion_v1_16 ? fEnabledOut : !fEnabledOut)
+        && fEnabledOut == true
+        && controllerType == AudioControllerType_AC97
+        && codecType == AudioCodecType_STAC9700
+        && properties.size() == 0;
+}
+
+/**
+ * Comparison operator. This gets called from MachineConfigFile::operator==,
+ * which in turn gets called from Machine::saveSettings to figure out whether
+ * machine settings have really changed and thus need to be written out to disk.
+ */
+bool AudioAdapter::operator==(const AudioAdapter &a) const
+{
+    return (this == &a)
+        || (   fEnabled        == a.fEnabled
+            && fEnabledIn      == a.fEnabledIn
+            && fEnabledOut     == a.fEnabledOut
+            && controllerType  == a.controllerType
+            && codecType       == a.codecType
+            && driverType      == a.driverType
+            && properties      == a.properties);
+}
+
+/**
+ * Constructor. Needs to set sane defaults which stand the test of time.
+ */
+SharedFolder::SharedFolder() :
+    fWritable(false),
+    fAutoMount(false)
+{
+}
+
+/**
+ * Comparison operator. This gets called from MachineConfigFile::operator==,
+ * which in turn gets called from Machine::saveSettings to figure out whether
+ * machine settings have really changed and thus need to be written out to disk.
+ */
+bool SharedFolder::operator==(const SharedFolder &g) const
+{
+    return (this == &g)
+        || (   strName           == g.strName
+            && strHostPath       == g.strHostPath
+            && fWritable         == g.fWritable
+            && fAutoMount        == g.fAutoMount
+            && strAutoMountPoint == g.strAutoMountPoint);
+}
+
+/**
+ * Constructor. Needs to set sane defaults which stand the test of time.
+ */
+GuestProperty::GuestProperty() :
+    timestamp(0)
+{
+}
+
+/**
+ * Comparison operator. This gets called from MachineConfigFile::operator==,
+ * which in turn gets called from Machine::saveSettings to figure out whether
+ * machine settings have really changed and thus need to be written out to disk.
+ */
+bool GuestProperty::operator==(const GuestProperty &g) const
+{
+    return (this == &g)
+        || (   strName           == g.strName
+            && strValue          == g.strValue
+            && timestamp         == g.timestamp
+            && strFlags          == g.strFlags);
+}
+
+/**
+ * Constructor. Needs to set sane defaults which stand the test of time.
+ */
+CpuIdLeaf::CpuIdLeaf() :
+    idx(UINT32_MAX),
+    idxSub(0),
+    uEax(0),
+    uEbx(0),
+    uEcx(0),
+    uEdx(0)
+{
+}
+
+/**
+ * Comparison operator. This gets called from MachineConfigFile::operator==,
+ * which in turn gets called from Machine::saveSettings to figure out whether
+ * machine settings have really changed and thus need to be written out to disk.
+ */
+bool CpuIdLeaf::operator==(const CpuIdLeaf &c) const
+{
+    return (this == &c)
+        || (   idx      == c.idx
+            && idxSub   == c.idxSub
+            && uEax     == c.uEax
+            && uEbx     == c.uEbx
+            && uEcx     == c.uEcx
+            && uEdx     == c.uEdx);
+}
+
+/**
+ * Constructor. Needs to set sane defaults which stand the test of time.
+ */
+Cpu::Cpu() :
+    ulId(UINT32_MAX)
+{
+}
+
+/**
+ * Comparison operator. This gets called from MachineConfigFile::operator==,
+ * which in turn gets called from Machine::saveSettings to figure out whether
+ * machine settings have really changed and thus need to be written out to disk.
+ */
+bool Cpu::operator==(const Cpu &c) const
+{
+    return (this == &c)
+        || (ulId      == c.ulId);
+}
+
+/**
+ * Constructor. Needs to set sane defaults which stand the test of time.
+ */
+BandwidthGroup::BandwidthGroup() :
+    cMaxBytesPerSec(0),
+    enmType(BandwidthGroupType_Null)
+{
+}
+
+/**
+ * Comparison operator. This gets called from MachineConfigFile::operator==,
+ * which in turn gets called from Machine::saveSettings to figure out whether
+ * machine settings have really changed and thus need to be written out to disk.
+ */
+bool BandwidthGroup::operator==(const BandwidthGroup &i) const
+{
+    return (this == &i)
+        || (   strName      == i.strName
+            && cMaxBytesPerSec == i.cMaxBytesPerSec
+            && enmType      == i.enmType);
+}
+
+/**
+ * IOSettings constructor.
+ */
+IOSettings::IOSettings() :
+    fIOCacheEnabled(true),
+    ulIOCacheSize(5)
+{
+}
+
+/**
+ * Check if all IO Cache settings have default values.
+ */
+bool IOSettings::areIOCacheDefaultSettings() const
+{
+    return fIOCacheEnabled
+        && ulIOCacheSize == 5;
+}
+
+/**
+ * Check if all settings have default values.
+ */
+bool IOSettings::areDefaultSettings() const
+{
+    return areIOCacheDefaultSettings()
+        && llBandwidthGroups.size() == 0;
+}
+
+/**
+ * Comparison operator. This gets called from MachineConfigFile::operator==,
+ * which in turn gets called from Machine::saveSettings to figure out whether
+ * machine settings have really changed and thus need to be written out to disk.
+ */
+bool IOSettings::operator==(const IOSettings &i) const
+{
+    return (this == &i)
+        || (   fIOCacheEnabled   == i.fIOCacheEnabled
+            && ulIOCacheSize     == i.ulIOCacheSize
+            && llBandwidthGroups == i.llBandwidthGroups);
+}
+
+/**
+ * Constructor. Needs to set sane defaults which stand the test of time.
+ */
+HostPCIDeviceAttachment::HostPCIDeviceAttachment() :
+    uHostAddress(0),
+    uGuestAddress(0)
+{
+}
+
+/**
+ * Comparison operator. This gets called from MachineConfigFile::operator==,
+ * which in turn gets called from Machine::saveSettings to figure out whether
+ * machine settings have really changed and thus need to be written out to disk.
+ */
+bool HostPCIDeviceAttachment::operator==(const HostPCIDeviceAttachment &a) const
+{
+    return (this == &a)
+        || (   uHostAddress   == a.uHostAddress
+            && uGuestAddress  == a.uGuestAddress
+            && strDeviceName  == a.strDeviceName);
+}
+
+
+/**
+ * Constructor. Needs to set sane defaults which stand the test of time.
+ */
+Hardware::Hardware() :
+    strVersion("1"),
+    fHardwareVirt(true),
+    fNestedPaging(true),
+    fVPID(true),
+    fUnrestrictedExecution(true),
+    fHardwareVirtForce(false),
+    fUseNativeApi(false),
+    fTripleFaultReset(false),
+    fPAE(false),
+    fAPIC(true),
+    fX2APIC(false),
+    fIBPBOnVMExit(false),
+    fIBPBOnVMEntry(false),
+    fSpecCtrl(false),
+    fSpecCtrlByHost(false),
+    fL1DFlushOnSched(true),
+    fL1DFlushOnVMEntry(false),
+    fMDSClearOnSched(true),
+    fMDSClearOnVMEntry(false),
+    fNestedHWVirt(false),
+    fVirtVmsaveVmload(true),
+    enmLongMode(HC_ARCH_BITS == 64 ? Hardware::LongMode_Enabled : Hardware::LongMode_Disabled),
+    cCPUs(1),
+    fCpuHotPlug(false),
+    fHPETEnabled(false),
+    ulCpuExecutionCap(100),
+    uCpuIdPortabilityLevel(0),
+    strCpuProfile("host"),
+    ulMemorySizeMB((uint32_t)-1),
+    firmwareType(FirmwareType_BIOS),
+    pointingHIDType(PointingHIDType_PS2Mouse),
+    keyboardHIDType(KeyboardHIDType_PS2Keyboard),
+    chipsetType(ChipsetType_PIIX3),
+    iommuType(IommuType_None),
+    paravirtProvider(ParavirtProvider_Legacy), // default for old VMs, for new ones it's ParavirtProvider_Default
+    strParavirtDebug(""),
+    fEmulatedUSBCardReader(false),
+    clipboardMode(ClipboardMode_Disabled),
+    fClipboardFileTransfersEnabled(false),
+    dndMode(DnDMode_Disabled),
+    ulMemoryBalloonSize(0),
+    fPageFusionEnabled(false)
+{
+    mapBootOrder[0] = DeviceType_Floppy;
+    mapBootOrder[1] = DeviceType_DVD;
+    mapBootOrder[2] = DeviceType_HardDisk;
+
+    /* The default value for PAE depends on the host:
+     * - 64 bits host -> always true
+     * - 32 bits host -> true for Windows & Darwin (masked off if the host cpu doesn't support it anyway)
+     */
+#if HC_ARCH_BITS == 64 || defined(RT_OS_WINDOWS) || defined(RT_OS_DARWIN)
+    fPAE = true;
+#endif
+
+    /* The default value of large page supports depends on the host:
+     * - 64 bits host -> true, unless it's Linux (pending further prediction work due to excessively expensive large page allocations)
+     * - 32 bits host -> false
+     */
+#if HC_ARCH_BITS == 64 && !defined(RT_OS_LINUX)
+    fLargePages = true;
+#else
+    /* Not supported on 32 bits hosts. */
+    fLargePages = false;
+#endif
+}
+
+/**
+ * Check if all Paravirt settings have default values.
+ */
+bool Hardware::areParavirtDefaultSettings(SettingsVersion_T sv) const
+{
+    // 5.0 didn't save the paravirt settings if it is ParavirtProvider_Legacy,
+    // so this default must be kept. Later versions don't save the setting if
+    // it's at the default value.
+    return (   (sv >= SettingsVersion_v1_16 && paravirtProvider == ParavirtProvider_Default)
+            || (sv < SettingsVersion_v1_16 && paravirtProvider == ParavirtProvider_Legacy))
+        && strParavirtDebug.isEmpty();
+}
+
+/**
+ * Check if all Boot Order settings have default values.
+ */
+bool Hardware::areBootOrderDefaultSettings() const
+{
+    BootOrderMap::const_iterator it0 = mapBootOrder.find(0);
+    BootOrderMap::const_iterator it1 = mapBootOrder.find(1);
+    BootOrderMap::const_iterator it2 = mapBootOrder.find(2);
+    BootOrderMap::const_iterator it3 = mapBootOrder.find(3);
+    return    (   mapBootOrder.size() == 3
+               || (   mapBootOrder.size() == 4
+                   && (it3 != mapBootOrder.end() && it3->second == DeviceType_Null)))
+           && (it0 != mapBootOrder.end() && it0->second == DeviceType_Floppy)
+           && (it1 != mapBootOrder.end() && it1->second == DeviceType_DVD)
+           && (it2 != mapBootOrder.end() && it2->second == DeviceType_HardDisk);
+}
+
+/**
+ * Check if all Network Adapter settings have default values.
+ */
+bool Hardware::areAllNetworkAdaptersDefaultSettings(SettingsVersion_T sv) const
+{
+    for (NetworkAdaptersList::const_iterator it = llNetworkAdapters.begin();
+         it != llNetworkAdapters.end();
+         ++it)
+    {
+        if (!it->areDefaultSettings(sv))
+            return false;
+    }
+    return true;
+}
+
+/**
+ * Comparison operator. This gets called from MachineConfigFile::operator==,
+ * which in turn gets called from Machine::saveSettings to figure out whether
+ * machine settings have really changed and thus need to be written out to disk.
+ */
+bool Hardware::operator==(const Hardware& h) const
+{
+    return (this == &h)
+        || (   strVersion                     == h.strVersion
+            && uuid                           == h.uuid
+            && fHardwareVirt                  == h.fHardwareVirt
+            && fNestedPaging                  == h.fNestedPaging
+            && fLargePages                    == h.fLargePages
+            && fVPID                          == h.fVPID
+            && fUnrestrictedExecution         == h.fUnrestrictedExecution
+            && fHardwareVirtForce             == h.fHardwareVirtForce
+            && fUseNativeApi                  == h.fUseNativeApi
+            && fPAE                           == h.fPAE
+            && enmLongMode                    == h.enmLongMode
+            && fTripleFaultReset              == h.fTripleFaultReset
+            && fAPIC                          == h.fAPIC
+            && fX2APIC                        == h.fX2APIC
+            && fIBPBOnVMExit                  == h.fIBPBOnVMExit
+            && fIBPBOnVMEntry                 == h.fIBPBOnVMEntry
+            && fSpecCtrl                      == h.fSpecCtrl
+            && fSpecCtrlByHost                == h.fSpecCtrlByHost
+            && fL1DFlushOnSched               == h.fL1DFlushOnSched
+            && fL1DFlushOnVMEntry             == h.fL1DFlushOnVMEntry
+            && fMDSClearOnSched               == h.fMDSClearOnSched
+            && fMDSClearOnVMEntry             == h.fMDSClearOnVMEntry
+            && fNestedHWVirt                  == h.fNestedHWVirt
+            && fVirtVmsaveVmload              == h.fVirtVmsaveVmload
+            && cCPUs                          == h.cCPUs
+            && fCpuHotPlug                    == h.fCpuHotPlug
+            && ulCpuExecutionCap              == h.ulCpuExecutionCap
+            && uCpuIdPortabilityLevel         == h.uCpuIdPortabilityLevel
+            && strCpuProfile                  == h.strCpuProfile
+            && fHPETEnabled                   == h.fHPETEnabled
+            && llCpus                         == h.llCpus
+            && llCpuIdLeafs                   == h.llCpuIdLeafs
+            && ulMemorySizeMB                 == h.ulMemorySizeMB
+            && mapBootOrder                   == h.mapBootOrder
+            && firmwareType                   == h.firmwareType
+            && pointingHIDType                == h.pointingHIDType
+            && keyboardHIDType                == h.keyboardHIDType
+            && chipsetType                    == h.chipsetType
+            && iommuType                      == h.iommuType
+            && paravirtProvider               == h.paravirtProvider
+            && strParavirtDebug               == h.strParavirtDebug
+            && fEmulatedUSBCardReader         == h.fEmulatedUSBCardReader
+            && vrdeSettings                   == h.vrdeSettings
+            && biosSettings                   == h.biosSettings
+            && nvramSettings                  == h.nvramSettings
+            && graphicsAdapter                == h.graphicsAdapter
+            && usbSettings                    == h.usbSettings
+            && tpmSettings                    == h.tpmSettings
+            && llNetworkAdapters              == h.llNetworkAdapters
+            && llSerialPorts                  == h.llSerialPorts
+            && llParallelPorts                == h.llParallelPorts
+            && audioAdapter                   == h.audioAdapter
+            && storage                        == h.storage
+            && llSharedFolders                == h.llSharedFolders
+            && clipboardMode                  == h.clipboardMode
+            && fClipboardFileTransfersEnabled == h.fClipboardFileTransfersEnabled
+            && dndMode                        == h.dndMode
+            && ulMemoryBalloonSize            == h.ulMemoryBalloonSize
+            && fPageFusionEnabled             == h.fPageFusionEnabled
+            && llGuestProperties              == h.llGuestProperties
+            && ioSettings                     == h.ioSettings
+            && pciAttachments                 == h.pciAttachments
+            && strDefaultFrontend             == h.strDefaultFrontend);
+}
+
+/**
+ * Constructor. Needs to set sane defaults which stand the test of time.
+ */
+AttachedDevice::AttachedDevice() :
+    deviceType(DeviceType_Null),
+    fPassThrough(false),
+    fTempEject(false),
+    fNonRotational(false),
+    fDiscard(false),
+    fHotPluggable(false),
+    lPort(0),
+    lDevice(0)
+{
+}
+
+/**
+ * Comparison operator. This gets called from MachineConfigFile::operator==,
+ * which in turn gets called from Machine::saveSettings to figure out whether
+ * machine settings have really changed and thus need to be written out to disk.
+ */
+bool AttachedDevice::operator==(const AttachedDevice &a) const
+{
+    return (this == &a)
+        || (   deviceType                == a.deviceType
+            && fPassThrough              == a.fPassThrough
+            && fTempEject                == a.fTempEject
+            && fNonRotational            == a.fNonRotational
+            && fDiscard                  == a.fDiscard
+            && fHotPluggable             == a.fHotPluggable
+            && lPort                     == a.lPort
+            && lDevice                   == a.lDevice
+            && uuid                      == a.uuid
+            && strHostDriveSrc           == a.strHostDriveSrc
+            && strBwGroup                == a.strBwGroup);
+}
+
+/**
+ * Constructor. Needs to set sane defaults which stand the test of time.
+ */
+StorageController::StorageController() :
+    storageBus(StorageBus_IDE),
+    controllerType(StorageControllerType_PIIX3),
+    ulPortCount(2),
+    ulInstance(0),
+    fUseHostIOCache(true),
+    fBootable(true)
+{
+}
+
+/**
+ * Comparison operator. This gets called from MachineConfigFile::operator==,
+ * which in turn gets called from Machine::saveSettings to figure out whether
+ * machine settings have really changed and thus need to be written out to disk.
+ */
+bool StorageController::operator==(const StorageController &s) const
+{
+    return (this == &s)
+        || (   strName                   == s.strName
+            && storageBus                == s.storageBus
+            && controllerType            == s.controllerType
+            && ulPortCount               == s.ulPortCount
+            && ulInstance                == s.ulInstance
+            && fUseHostIOCache           == s.fUseHostIOCache
+            && llAttachedDevices         == s.llAttachedDevices);
+}
+
+/**
+ * Comparison operator. This gets called from MachineConfigFile::operator==,
+ * which in turn gets called from Machine::saveSettings to figure out whether
+ * machine settings have really changed and thus need to be written out to disk.
+ */
+bool Storage::operator==(const Storage &s) const
+{
+    return (this == &s)
+        || (llStorageControllers == s.llStorageControllers);            // deep compare
+}
+
+/**
+ * Constructor. Needs to set sane defaults which stand the test of time.
+ */
+Debugging::Debugging() :
+    fTracingEnabled(false),
+    fAllowTracingToAccessVM(false),
+    strTracingConfig(),
+    enmDbgProvider(GuestDebugProvider_None),
+    enmIoProvider(GuestDebugIoProvider_None),
+    strAddress(),
+    ulPort(0)
+{
+}
+
+/**
+ * Check if all settings have default values.
+ */
+bool Debugging::areDefaultSettings() const
+{
+    return !fTracingEnabled
+        && !fAllowTracingToAccessVM
+        && strTracingConfig.isEmpty()
+        && enmDbgProvider == GuestDebugProvider_None
+        && enmIoProvider == GuestDebugIoProvider_None
+        && strAddress.isEmpty()
+        && ulPort == 0;
+}
+
+/**
+ * Comparison operator. This gets called from MachineConfigFile::operator==,
+ * which in turn gets called from Machine::saveSettings to figure out whether
+ * machine settings have really changed and thus need to be written out to disk.
+ */
+bool Debugging::operator==(const Debugging &d) const
+{
+    return (this == &d)
+        || (   fTracingEnabled          == d.fTracingEnabled
+            && fAllowTracingToAccessVM  == d.fAllowTracingToAccessVM
+            && strTracingConfig         == d.strTracingConfig
+            && enmDbgProvider           == d.enmDbgProvider
+            && enmIoProvider            == d.enmIoProvider
+            && strAddress               == d.strAddress
+            && ulPort                   == d.ulPort);
+}
+
+/**
+ * Constructor. Needs to set sane defaults which stand the test of time.
+ */
+Autostart::Autostart() :
+    fAutostartEnabled(false),
+    uAutostartDelay(0),
+    enmAutostopType(AutostopType_Disabled)
+{
+}
+
+/**
+ * Check if all settings have default values.
+ */
+bool Autostart::areDefaultSettings() const
+{
+    return !fAutostartEnabled
+        && !uAutostartDelay
+        && enmAutostopType == AutostopType_Disabled;
+}
+
+/**
+ * Comparison operator. This gets called from MachineConfigFile::operator==,
+ * which in turn gets called from Machine::saveSettings to figure out whether
+ * machine settings have really changed and thus need to be written out to disk.
+ */
+bool Autostart::operator==(const Autostart &a) const
+{
+    return (this == &a)
+        || (   fAutostartEnabled == a.fAutostartEnabled
+            && uAutostartDelay   == a.uAutostartDelay
+            && enmAutostopType   == a.enmAutostopType);
+}
+
+/**
+ * Constructor. Needs to set sane defaults which stand the test of time.
+ */
+Snapshot::Snapshot()
+{
+    RTTimeSpecSetNano(&timestamp, 0);
+}
+
+/**
+ * Comparison operator. This gets called from MachineConfigFile::operator==,
+ * which in turn gets called from Machine::saveSettings to figure out whether
+ * machine settings have really changed and thus need to be written out to disk.
+ */
+bool Snapshot::operator==(const Snapshot &s) const
+{
+    return (this == &s)
+        || (   uuid                  == s.uuid
+            && strName               == s.strName
+            && strDescription        == s.strDescription
+            && RTTimeSpecIsEqual(&timestamp, &s.timestamp)
+            && strStateFile          == s.strStateFile
+            && hardware              == s.hardware                  // deep compare
+            && recordingSettings     == s.recordingSettings         // deep compare
+            && llChildSnapshots      == s.llChildSnapshots          // deep compare
+            && debugging             == s.debugging
+            && autostart             == s.autostart);
+}
+
+const struct Snapshot settings::Snapshot::Empty; /* default ctor is OK */
+
+/**
+ * Constructor. Needs to set sane defaults which stand the test of time.
+ */
+MachineUserData::MachineUserData() :
+    fDirectoryIncludesUUID(false),
+    fNameSync(true),
+    fTeleporterEnabled(false),
+    uTeleporterPort(0),
+    fRTCUseUTC(false),
+    enmVMPriority(VMProcPriority_Default)
+{
+    llGroups.push_back("/");
+}
+
+/**
+ * Comparison operator. This gets called from MachineConfigFile::operator==,
+ * which in turn gets called from Machine::saveSettings to figure out whether
+ * machine settings have really changed and thus need to be written out to disk.
+ */
+bool MachineUserData::operator==(const MachineUserData &c) const
+{
+    return (this == &c)
+        || (   strName                    == c.strName
+            && fDirectoryIncludesUUID     == c.fDirectoryIncludesUUID
+            && fNameSync                  == c.fNameSync
+            && strDescription             == c.strDescription
+            && llGroups                   == c.llGroups
+            && strOsType                  == c.strOsType
+            && strSnapshotFolder          == c.strSnapshotFolder
+            && fTeleporterEnabled         == c.fTeleporterEnabled
+            && uTeleporterPort            == c.uTeleporterPort
+            && strTeleporterAddress       == c.strTeleporterAddress
+            && strTeleporterPassword      == c.strTeleporterPassword
+            && fRTCUseUTC                 == c.fRTCUseUTC
+            && ovIcon                     == c.ovIcon
+            && enmVMPriority              == c.enmVMPriority);
+}
+
+
+////////////////////////////////////////////////////////////////////////////////
+//
+// MachineConfigFile
+//
+////////////////////////////////////////////////////////////////////////////////
+
+/**
+ * Constructor.
+ *
+ * If pstrFilename is != NULL, this reads the given settings file into the member
+ * variables and various substructures and lists. Otherwise, the member variables
+ * are initialized with default values.
+ *
+ * Throws variants of xml::Error for I/O, XML and logical content errors, which
+ * the caller should catch; if this constructor does not throw, then the member
+ * variables contain meaningful values (either from the file or defaults).
+ *
+ * @param pstrFilename
+ * @param pCryptoIf             Pointer to the cryptographic interface, required for an encrypted machine config.
+ * @param pszPassword           The password to use for an encrypted machine config.
+ */
+MachineConfigFile::MachineConfigFile(const Utf8Str *pstrFilename, PCVBOXCRYPTOIF pCryptoIf, const char *pszPassword)
+    : ConfigFileBase(pstrFilename),
+      enmParseState(ParseState_NotParsed),
+      fCurrentStateModified(true),
+      fAborted(false)
+{
+    RTTimeNow(&timeLastStateChange);
+
+    if (pstrFilename)
+    {
+        // the ConfigFileBase constructor has loaded the XML file, so now
+        // we need only analyze what is in there
+
+        xml::NodesLoop nlRootChildren(*m->pelmRoot);
+        const xml::ElementNode *pelmRootChild;
+        while ((pelmRootChild = nlRootChildren.forAllNodes()))
+        {
+            if (pelmRootChild->nameEquals("MachineEncrypted"))
+                readMachineEncrypted(*pelmRootChild, pCryptoIf, pszPassword);
+            if (pelmRootChild->nameEquals("Machine"))
+                readMachine(*pelmRootChild);
+        }
+
+        // clean up memory allocated by XML engine
+        clearDocument();
+
+        if (enmParseState == ParseState_NotParsed)
+            enmParseState = ParseState_Parsed;
+    }
+}
+
+/**
+ * Public routine which returns true if this machine config file can have its
+ * own media registry (which is true for settings version v1.11 and higher,
+ * i.e. files created by VirtualBox 4.0 and higher).
+ * @return
+ */
+bool MachineConfigFile::canHaveOwnMediaRegistry() const
+{
+    return (m->sv >= SettingsVersion_v1_11);
+}
+
+/**
+ * Public routine which copies encryption settings. Used by Machine::saveSettings
+ * so that the encryption settings do not get lost when a copy of the Machine settings
+ * file is made to see if settings have actually changed.
+ * @param other
+ */
+void MachineConfigFile::copyEncryptionSettingsFrom(const MachineConfigFile &other)
+{
+    strKeyId    = other.strKeyId;
+    strKeyStore = other.strKeyStore;
+}
+
+/**
+ * Public routine which allows for importing machine XML from an external DOM tree.
+ * Use this after having called the constructor with a NULL argument.
+ *
+ * This is used by the OVF code if a <vbox:Machine> element has been encountered
+ * in an OVF VirtualSystem element.
+ *
+ * @param elmMachine
+ */
+void MachineConfigFile::importMachineXML(const xml::ElementNode &elmMachine)
+{
+    // Ideally the version should be mandatory, but since VirtualBox didn't
+    // care about it until 5.1 came with different defaults, there are OVF
+    // files created by magicians (not using VirtualBox, which always wrote it)
+    // which lack this information. Let's hope that they learn to add the
+    // version when they switch to the newer settings style/defaults of 5.1.
+    if (!(elmMachine.getAttributeValue("version", m->strSettingsVersionFull)))
+        m->strSettingsVersionFull = VBOX_XML_IMPORT_VERSION_FULL;
+
+    LogRel(("Import settings with version \"%s\"\n", m->strSettingsVersionFull.c_str()));
+
+    m->sv = parseVersion(m->strSettingsVersionFull, &elmMachine);
+
+    // remember the settings version we read in case it gets upgraded later,
+    // so we know when to make backups
+    m->svRead = m->sv;
+
+    readMachine(elmMachine);
+}
+
+/**
+ * Comparison operator. This gets called from Machine::saveSettings to figure out
+ * whether machine settings have really changed and thus need to be written out to disk.
+ *
+ * Even though this is called operator==, this does NOT compare all fields; the "equals"
+ * should be understood as "has the same machine config as". The following fields are
+ * NOT compared:
+ *      -- settings versions and file names inherited from ConfigFileBase;
+ *      -- fCurrentStateModified because that is considered separately in Machine::saveSettings!!
+ *
+ * The "deep" comparisons marked below will invoke the operator== functions of the
+ * structs defined in this file, which may in turn go into comparing lists of
+ * other structures. As a result, invoking this can be expensive, but it's
+ * less expensive than writing out XML to disk.
+ */
+bool MachineConfigFile::operator==(const MachineConfigFile &c) const
+{
+    return (this == &c)
+        || (   uuid                       == c.uuid
+            && machineUserData            == c.machineUserData
+            && strStateFile               == c.strStateFile
+            && uuidCurrentSnapshot        == c.uuidCurrentSnapshot
+            // skip fCurrentStateModified!
+            && RTTimeSpecIsEqual(&timeLastStateChange, &c.timeLastStateChange)
+            && fAborted                   == c.fAborted
+            && hardwareMachine            == c.hardwareMachine      // this one's deep
+            && mediaRegistry              == c.mediaRegistry        // this one's deep
+            // skip mapExtraDataItems! there is no old state available as it's always forced
+            && llFirstSnapshot            == c.llFirstSnapshot     // this one's deep
+            && recordingSettings          == c.recordingSettings   // this one's deep
+            && strKeyId                   == c.strKeyId
+            && strKeyStore                == c.strKeyStore
+            && strStateKeyId              == c.strStateKeyId
+            && strStateKeyStore           == c.strStateKeyStore
+            && strLogKeyId                == c.strLogKeyId
+            && strLogKeyStore             == c.strLogKeyStore);
+}
+
+/**
+ * Called from MachineConfigFile::readHardware() to read cpu information.
+ * @param elmCpu
+ * @param ll
+ */
+void MachineConfigFile::readCpuTree(const xml::ElementNode &elmCpu,
+                                    CpuList &ll)
+{
+    xml::NodesLoop nl1(elmCpu, "Cpu");
+    const xml::ElementNode *pelmCpu;
+    while ((pelmCpu = nl1.forAllNodes()))
+    {
+        Cpu cpu;
+
+        if (!pelmCpu->getAttributeValue("id", cpu.ulId))
+            throw ConfigFileError(this, pelmCpu, N_("Required Cpu/@id attribute is missing"));
+
+        ll.push_back(cpu);
+    }
+}
+
+/**
+ * Called from MachineConfigFile::readHardware() to cpuid information.
+ * @param elmCpuid
+ * @param ll
+ */
+void MachineConfigFile::readCpuIdTree(const xml::ElementNode &elmCpuid,
+                                      CpuIdLeafsList &ll)
+{
+    xml::NodesLoop nl1(elmCpuid, "CpuIdLeaf");
+    const xml::ElementNode *pelmCpuIdLeaf;
+    while ((pelmCpuIdLeaf = nl1.forAllNodes()))
+    {
+        CpuIdLeaf leaf;
+
+        if (!pelmCpuIdLeaf->getAttributeValue("id", leaf.idx))
+            throw ConfigFileError(this, pelmCpuIdLeaf, N_("Required CpuId/@id attribute is missing"));
+
+        if (!pelmCpuIdLeaf->getAttributeValue("subleaf", leaf.idxSub))
+            leaf.idxSub = 0;
+        pelmCpuIdLeaf->getAttributeValue("eax", leaf.uEax);
+        pelmCpuIdLeaf->getAttributeValue("ebx", leaf.uEbx);
+        pelmCpuIdLeaf->getAttributeValue("ecx", leaf.uEcx);
+        pelmCpuIdLeaf->getAttributeValue("edx", leaf.uEdx);
+
+        ll.push_back(leaf);
+    }
+}
+
+/**
+ * Called from MachineConfigFile::readHardware() to network information.
+ * @param elmNetwork
+ * @param ll
+ */
+void MachineConfigFile::readNetworkAdapters(const xml::ElementNode &elmNetwork,
+                                            NetworkAdaptersList &ll)
+{
+    xml::NodesLoop nl1(elmNetwork, "Adapter");
+    const xml::ElementNode *pelmAdapter;
+    while ((pelmAdapter = nl1.forAllNodes()))
+    {
+        NetworkAdapter nic;
+
+        if (m->sv >= SettingsVersion_v1_16)
+        {
+            /* Starting with VirtualBox 5.1 the default is cable connected and
+             * PCnet-FAST III. Needs to match NetworkAdapter.areDefaultSettings(). */
+            nic.fCableConnected = true;
+            nic.type = NetworkAdapterType_Am79C973;
+        }
+
+        if (!pelmAdapter->getAttributeValue("slot", nic.ulSlot))
+            throw ConfigFileError(this, pelmAdapter, N_("Required Adapter/@slot attribute is missing"));
+
+        Utf8Str strTemp;
+        if (pelmAdapter->getAttributeValue("type", strTemp))
+        {
+            if (strTemp == "Am79C970A")
+                nic.type = NetworkAdapterType_Am79C970A;
+            else if (strTemp == "Am79C973")
+                nic.type = NetworkAdapterType_Am79C973;
+            else if (strTemp == "Am79C960")
+                nic.type = NetworkAdapterType_Am79C960;
+            else if (strTemp == "82540EM")
+                nic.type = NetworkAdapterType_I82540EM;
+            else if (strTemp == "82543GC")
+                nic.type = NetworkAdapterType_I82543GC;
+            else if (strTemp == "82545EM")
+                nic.type = NetworkAdapterType_I82545EM;
+            else if (strTemp == "virtio")
+                nic.type = NetworkAdapterType_Virtio;
+            else if (strTemp == "NE1000")
+                nic.type = NetworkAdapterType_NE1000;
+            else if (strTemp == "NE2000")
+                nic.type = NetworkAdapterType_NE2000;
+            else if (strTemp == "WD8003")
+                nic.type = NetworkAdapterType_WD8003;
+            else if (strTemp == "WD8013")
+                nic.type = NetworkAdapterType_WD8013;
+            else if (strTemp == "3C503")
+                nic.type = NetworkAdapterType_ELNK2;
+            else if (strTemp == "3C501")
+                nic.type = NetworkAdapterType_ELNK1;
+            else
+                throw ConfigFileError(this, pelmAdapter, N_("Invalid value '%s' in Adapter/@type attribute"), strTemp.c_str());
+        }
+
+        pelmAdapter->getAttributeValue("enabled", nic.fEnabled);
+        pelmAdapter->getAttributeValue("MACAddress", nic.strMACAddress);
+        pelmAdapter->getAttributeValue("cable", nic.fCableConnected);
+        pelmAdapter->getAttributeValue("speed", nic.ulLineSpeed);
+
+        if (pelmAdapter->getAttributeValue("promiscuousModePolicy", strTemp))
+        {
+            if (strTemp == "Deny")
+                nic.enmPromiscModePolicy = NetworkAdapterPromiscModePolicy_Deny;
+            else if (strTemp == "AllowNetwork")
+                nic.enmPromiscModePolicy = NetworkAdapterPromiscModePolicy_AllowNetwork;
+            else if (strTemp == "AllowAll")
+                nic.enmPromiscModePolicy = NetworkAdapterPromiscModePolicy_AllowAll;
+            else
+                throw ConfigFileError(this, pelmAdapter,
+                                      N_("Invalid value '%s' in Adapter/@promiscuousModePolicy attribute"), strTemp.c_str());
+        }
+
+        pelmAdapter->getAttributeValue("trace", nic.fTraceEnabled);
+        pelmAdapter->getAttributeValue("tracefile", nic.strTraceFile);
+        pelmAdapter->getAttributeValue("bootPriority", nic.ulBootPriority);
+        pelmAdapter->getAttributeValue("bandwidthGroup", nic.strBandwidthGroup);
+
+        xml::ElementNodesList llNetworkModes;
+        pelmAdapter->getChildElements(llNetworkModes);
+        xml::ElementNodesList::iterator it;
+        /* We should have only active mode descriptor and disabled modes set */
+        if (llNetworkModes.size() > 2)
+        {
+            throw ConfigFileError(this, pelmAdapter, N_("Invalid number of modes ('%d') attached to Adapter attribute"), llNetworkModes.size());
+        }
+        for (it = llNetworkModes.begin(); it != llNetworkModes.end(); ++it)
+        {
+            const xml::ElementNode *pelmNode = *it;
+            if (pelmNode->nameEquals("DisabledModes"))
+            {
+                xml::ElementNodesList llDisabledNetworkModes;
+                xml::ElementNodesList::iterator itDisabled;
+                pelmNode->getChildElements(llDisabledNetworkModes);
+                /* run over disabled list and load settings */
+                for (itDisabled = llDisabledNetworkModes.begin();
+                     itDisabled != llDisabledNetworkModes.end(); ++itDisabled)
+                {
+                    const xml::ElementNode *pelmDisabledNode = *itDisabled;
+                    readAttachedNetworkMode(*pelmDisabledNode, false, nic);
+                }
+            }
+            else
+                readAttachedNetworkMode(*pelmNode, true, nic);
+        }
+        // else: default is NetworkAttachmentType_Null
+
+        ll.push_back(nic);
+    }
+}
+
+void MachineConfigFile::readAttachedNetworkMode(const xml::ElementNode &elmMode, bool fEnabled, NetworkAdapter &nic)
+{
+    NetworkAttachmentType_T enmAttachmentType = NetworkAttachmentType_Null;
+
+    if (elmMode.nameEquals("NAT"))
+    {
+        enmAttachmentType = NetworkAttachmentType_NAT;
+
+        elmMode.getAttributeValue("network", nic.nat.strNetwork);
+        elmMode.getAttributeValue("hostip", nic.nat.strBindIP);
+        elmMode.getAttributeValue("mtu", nic.nat.u32Mtu);
+        elmMode.getAttributeValue("sockrcv", nic.nat.u32SockRcv);
+        elmMode.getAttributeValue("socksnd", nic.nat.u32SockSnd);
+        elmMode.getAttributeValue("tcprcv", nic.nat.u32TcpRcv);
+        elmMode.getAttributeValue("tcpsnd", nic.nat.u32TcpSnd);
+        elmMode.getAttributeValue("localhost-reachable", nic.nat.fLocalhostReachable);
+        const xml::ElementNode *pelmDNS;
+        if ((pelmDNS = elmMode.findChildElement("DNS")))
+        {
+            pelmDNS->getAttributeValue("pass-domain", nic.nat.fDNSPassDomain);
+            pelmDNS->getAttributeValue("use-proxy", nic.nat.fDNSProxy);
+            pelmDNS->getAttributeValue("use-host-resolver", nic.nat.fDNSUseHostResolver);
+        }
+        const xml::ElementNode *pelmAlias;
+        if ((pelmAlias = elmMode.findChildElement("Alias")))
+        {
+            pelmAlias->getAttributeValue("logging", nic.nat.fAliasLog);
+            pelmAlias->getAttributeValue("proxy-only", nic.nat.fAliasProxyOnly);
+            pelmAlias->getAttributeValue("use-same-ports", nic.nat.fAliasUseSamePorts);
+        }
+        const xml::ElementNode *pelmTFTP;
+        if ((pelmTFTP = elmMode.findChildElement("TFTP")))
+        {
+            pelmTFTP->getAttributeValue("prefix", nic.nat.strTFTPPrefix);
+            pelmTFTP->getAttributeValue("boot-file", nic.nat.strTFTPBootFile);
+            pelmTFTP->getAttributeValue("next-server", nic.nat.strTFTPNextServer);
+        }
+
+        readNATForwardRulesMap(elmMode, nic.nat.mapRules);
+    }
+    else if (   elmMode.nameEquals("HostInterface")
+             || elmMode.nameEquals("BridgedInterface"))
+    {
+        enmAttachmentType = NetworkAttachmentType_Bridged;
+
+        // optional network name, cannot be required or we have trouble with
+        // settings which are saved before configuring the network name
+        elmMode.getAttributeValue("name", nic.strBridgedName);
+    }
+    else if (elmMode.nameEquals("InternalNetwork"))
+    {
+        enmAttachmentType = NetworkAttachmentType_Internal;
+
+        // optional network name, cannot be required or we have trouble with
+        // settings which are saved before configuring the network name
+        elmMode.getAttributeValue("name", nic.strInternalNetworkName);
+    }
+    else if (elmMode.nameEquals("HostOnlyInterface"))
+    {
+        enmAttachmentType = NetworkAttachmentType_HostOnly;
+
+        // optional network name, cannot be required or we have trouble with
+        // settings which are saved before configuring the network name
+        elmMode.getAttributeValue("name", nic.strHostOnlyName);
+    }
+#ifdef VBOX_WITH_VMNET
+    else if (elmMode.nameEquals("HostOnlyNetwork"))
+    {
+        enmAttachmentType = NetworkAttachmentType_HostOnlyNetwork;
+
+        // optional network name, cannot be required or we have trouble with
+        // settings which are saved before configuring the network name
+        elmMode.getAttributeValue("name", nic.strHostOnlyNetworkName);
+    }
+#endif /* VBOX_WITH_VMNET */
+    else if (elmMode.nameEquals("GenericInterface"))
+    {
+        enmAttachmentType = NetworkAttachmentType_Generic;
+
+        elmMode.getAttributeValue("driver", nic.strGenericDriver);  // optional network attachment driver
+
+        // get all properties
+        xml::NodesLoop nl(elmMode);
+        const xml::ElementNode *pelmModeChild;
+        while ((pelmModeChild = nl.forAllNodes()))
+        {
+            if (pelmModeChild->nameEquals("Property"))
+            {
+                Utf8Str strPropName, strPropValue;
+                if (   pelmModeChild->getAttributeValue("name", strPropName)
+                    && pelmModeChild->getAttributeValue("value", strPropValue) )
+                    nic.genericProperties[strPropName] = strPropValue;
+                else
+                    throw ConfigFileError(this, pelmModeChild, N_("Required GenericInterface/Property/@name or @value attribute is missing"));
+            }
+        }
+    }
+    else if (elmMode.nameEquals("NATNetwork"))
+    {
+        enmAttachmentType = NetworkAttachmentType_NATNetwork;
+
+        // optional network name, cannot be required or we have trouble with
+        // settings which are saved before configuring the network name
+        elmMode.getAttributeValue("name", nic.strNATNetworkName);
+    }
+    else if (elmMode.nameEquals("VDE"))
+    {
+        // inofficial hack (VDE networking was never part of the official
+        // settings, so it's not mentioned in VirtualBox-settings.xsd)
+        enmAttachmentType = NetworkAttachmentType_Generic;
+
+        com::Utf8Str strVDEName;
+        elmMode.getAttributeValue("network", strVDEName);   // optional network name
+        nic.strGenericDriver = "VDE";
+        nic.genericProperties["network"] = strVDEName;
+    }
+#ifdef VBOX_WITH_VMNET
+    else if (elmMode.nameEquals("HostOnlyNetwork"))
+    {
+        enmAttachmentType = NetworkAttachmentType_HostOnly;
+
+        // optional network name, cannot be required or we have trouble with
+        // settings which are saved before configuring the network name
+        elmMode.getAttributeValue("name", nic.strHostOnlyNetworkName);
+    }
+#endif /* VBOX_WITH_VMNET */
+#ifdef VBOX_WITH_CLOUD_NET
+    else if (elmMode.nameEquals("CloudNetwork"))
+    {
+        enmAttachmentType = NetworkAttachmentType_Cloud;
+
+        // optional network name, cannot be required or we have trouble with
+        // settings which are saved before configuring the network name
+        elmMode.getAttributeValue("name", nic.strCloudNetworkName);
+    }
+#endif /* VBOX_WITH_CLOUD_NET */
+
+    if (fEnabled && enmAttachmentType != NetworkAttachmentType_Null)
+        nic.mode = enmAttachmentType;
+}
+
+/**
+ * Called from MachineConfigFile::readHardware() to read serial port information.
+ * @param elmUART
+ * @param ll
+ */
+void MachineConfigFile::readSerialPorts(const xml::ElementNode &elmUART,
+                                        SerialPortsList &ll)
+{
+    xml::NodesLoop nl1(elmUART, "Port");
+    const xml::ElementNode *pelmPort;
+    while ((pelmPort = nl1.forAllNodes()))
+    {
+        SerialPort port;
+        if (!pelmPort->getAttributeValue("slot", port.ulSlot))
+            throw ConfigFileError(this, pelmPort, N_("Required UART/Port/@slot attribute is missing"));
+
+        // slot must be unique
+        for (SerialPortsList::const_iterator it = ll.begin();
+             it != ll.end();
+             ++it)
+            if ((*it).ulSlot == port.ulSlot)
+                throw ConfigFileError(this, pelmPort, N_("Invalid value %RU32 in UART/Port/@slot attribute: value is not unique"), port.ulSlot);
+
+        if (!pelmPort->getAttributeValue("enabled", port.fEnabled))
+            throw ConfigFileError(this, pelmPort, N_("Required UART/Port/@enabled attribute is missing"));
+        if (!pelmPort->getAttributeValue("IOBase", port.ulIOBase))
+            throw ConfigFileError(this, pelmPort, N_("Required UART/Port/@IOBase attribute is missing"));
+        if (!pelmPort->getAttributeValue("IRQ", port.ulIRQ))
+            throw ConfigFileError(this, pelmPort, N_("Required UART/Port/@IRQ attribute is missing"));
+
+        Utf8Str strPortMode;
+        if (!pelmPort->getAttributeValue("hostMode", strPortMode))
+            throw ConfigFileError(this, pelmPort, N_("Required UART/Port/@hostMode attribute is missing"));
+        if (strPortMode == "RawFile")
+            port.portMode = PortMode_RawFile;
+        else if (strPortMode == "HostPipe")
+            port.portMode = PortMode_HostPipe;
+        else if (strPortMode == "HostDevice")
+            port.portMode = PortMode_HostDevice;
+        else if (strPortMode == "Disconnected")
+            port.portMode = PortMode_Disconnected;
+        else if (strPortMode == "TCP")
+            port.portMode = PortMode_TCP;
+        else
+            throw ConfigFileError(this, pelmPort, N_("Invalid value '%s' in UART/Port/@hostMode attribute"), strPortMode.c_str());
+
+        pelmPort->getAttributeValue("path", port.strPath);
+        pelmPort->getAttributeValue("server", port.fServer);
+
+        Utf8Str strUartType;
+        if (pelmPort->getAttributeValue("uartType", strUartType))
+        {
+            if (strUartType == "16450")
+                port.uartType = UartType_U16450;
+            else if (strUartType == "16550A")
+                port.uartType = UartType_U16550A;
+            else if (strUartType == "16750")
+                port.uartType = UartType_U16750;
+            else
+                throw ConfigFileError(this, pelmPort, N_("Invalid value '%s' in UART/Port/@uartType attribute"), strUartType.c_str());
+        }
+
+        ll.push_back(port);
+    }
+}
+
+/**
+ * Called from MachineConfigFile::readHardware() to read parallel port information.
+ * @param elmLPT
+ * @param ll
+ */
+void MachineConfigFile::readParallelPorts(const xml::ElementNode &elmLPT,
+                                          ParallelPortsList &ll)
+{
+    xml::NodesLoop nl1(elmLPT, "Port");
+    const xml::ElementNode *pelmPort;
+    while ((pelmPort = nl1.forAllNodes()))
+    {
+        ParallelPort port;
+        if (!pelmPort->getAttributeValue("slot", port.ulSlot))
+            throw ConfigFileError(this, pelmPort, N_("Required LPT/Port/@slot attribute is missing"));
+
+        // slot must be unique
+        for (ParallelPortsList::const_iterator it = ll.begin();
+             it != ll.end();
+             ++it)
+            if ((*it).ulSlot == port.ulSlot)
+                throw ConfigFileError(this, pelmPort, N_("Invalid value %RU32 in LPT/Port/@slot attribute: value is not unique"), port.ulSlot);
+
+        if (!pelmPort->getAttributeValue("enabled", port.fEnabled))
+            throw ConfigFileError(this, pelmPort, N_("Required LPT/Port/@enabled attribute is missing"));
+        if (!pelmPort->getAttributeValue("IOBase", port.ulIOBase))
+            throw ConfigFileError(this, pelmPort, N_("Required LPT/Port/@IOBase attribute is missing"));
+        if (!pelmPort->getAttributeValue("IRQ", port.ulIRQ))
+            throw ConfigFileError(this, pelmPort, N_("Required LPT/Port/@IRQ attribute is missing"));
+
+        pelmPort->getAttributeValue("path", port.strPath);
+
+        ll.push_back(port);
+    }
+}
+
+/**
+ * Called from MachineConfigFile::readHardware() to read audio adapter information
+ * and maybe fix driver information depending on the current host hardware.
+ *
+ * @param elmAudioAdapter "AudioAdapter" XML element.
+ * @param aa
+ */
+void MachineConfigFile::readAudioAdapter(const xml::ElementNode &elmAudioAdapter,
+                                         AudioAdapter &aa)
+{
+    if (m->sv >= SettingsVersion_v1_15)
+    {
+        // get all properties
+        xml::NodesLoop nl1(elmAudioAdapter, "Property");
+        const xml::ElementNode *pelmModeChild;
+        while ((pelmModeChild = nl1.forAllNodes()))
+        {
+            Utf8Str strPropName, strPropValue;
+            if (   pelmModeChild->getAttributeValue("name", strPropName)
+                && pelmModeChild->getAttributeValue("value", strPropValue) )
+                aa.properties[strPropName] = strPropValue;
+            else
+                throw ConfigFileError(this, pelmModeChild, N_("Required AudioAdapter/Property/@name or @value attribute "
+                                                              "is missing"));
+        }
+    }
+
+    elmAudioAdapter.getAttributeValue("enabled", aa.fEnabled);
+    elmAudioAdapter.getAttributeValue("enabledIn", aa.fEnabledIn);
+    elmAudioAdapter.getAttributeValue("enabledOut", aa.fEnabledOut);
+
+    Utf8Str strTemp;
+    if (elmAudioAdapter.getAttributeValue("controller", strTemp))
+    {
+        if (strTemp == "SB16")
+            aa.controllerType = AudioControllerType_SB16;
+        else if (strTemp == "AC97")
+            aa.controllerType = AudioControllerType_AC97;
+        else if (strTemp == "HDA")
+            aa.controllerType = AudioControllerType_HDA;
+        else
+            throw ConfigFileError(this, &elmAudioAdapter, N_("Invalid value '%s' in AudioAdapter/@controller attribute"), strTemp.c_str());
+    }
+
+    if (elmAudioAdapter.getAttributeValue("codec", strTemp))
+    {
+        if (strTemp == "SB16")
+            aa.codecType = AudioCodecType_SB16;
+        else if (strTemp == "STAC9700")
+            aa.codecType = AudioCodecType_STAC9700;
+        else if (strTemp == "AD1980")
+            aa.codecType = AudioCodecType_AD1980;
+        else if (strTemp == "STAC9221")
+            aa.codecType = AudioCodecType_STAC9221;
+        else
+            throw ConfigFileError(this, &elmAudioAdapter, N_("Invalid value '%s' in AudioAdapter/@codec attribute"), strTemp.c_str());
+    }
+    else
+    {
+        /* No codec attribute provided; use defaults. */
+        switch (aa.controllerType)
+        {
+            case AudioControllerType_AC97:
+                aa.codecType = AudioCodecType_STAC9700;
+                break;
+            case AudioControllerType_SB16:
+                aa.codecType = AudioCodecType_SB16;
+                break;
+            case AudioControllerType_HDA:
+                aa.codecType = AudioCodecType_STAC9221;
+                break;
+            default:
+                Assert(false);  /* We just checked the controller type above. */
+        }
+    }
+
+    if (elmAudioAdapter.getAttributeValue("driver", strTemp))
+    {
+        // settings before 1.3 used lower case so make sure this is case-insensitive
+        strTemp.toUpper();
+        if (strTemp == "DEFAULT") /* Keep this to be backwards compatible for settings < r152556. */
+            aa.driverType = AudioDriverType_Default;
+        else if (strTemp == "NULL")
+            aa.driverType = AudioDriverType_Null;
+        else if (strTemp == "WAS")
+            aa.driverType = AudioDriverType_WAS;
+        else if (strTemp == "WINMM")
+            aa.driverType = AudioDriverType_WinMM;
+        else if ( (strTemp == "DIRECTSOUND") || (strTemp == "DSOUND") )
+            aa.driverType = AudioDriverType_DirectSound;
+        else if (strTemp == "SOLAUDIO") /* Deprecated -- Solaris will use OSS by default now. */
+            aa.driverType = AudioDriverType_SolAudio;
+        else if (strTemp == "ALSA")
+            aa.driverType = AudioDriverType_ALSA;
+        else if (strTemp == "PULSE")
+            aa.driverType = AudioDriverType_Pulse;
+        else if (strTemp == "OSS")
+            aa.driverType = AudioDriverType_OSS;
+        else if (strTemp == "COREAUDIO")
+            aa.driverType = AudioDriverType_CoreAudio;
+        else if (strTemp == "MMPM") /* Deprecated; only kept for backwards compatibility. */
+            aa.driverType = AudioDriverType_MMPM;
+        else
+        {
+            /* Be nice when loading the settings on downgraded versions: In case the selected backend isn't available / known
+             * to this version, fall back to the default backend, telling the user in the release log. See @bugref{10051c7}. */
+            LogRel(("WARNING: Invalid value '%s' in AudioAdapter/@driver attribute found; falling back to default audio backend\n",
+                    strTemp.c_str()));
+            aa.driverType = AudioDriverType_Default;
+        }
+
+        /* When loading settings >= 1.19 (VBox 7.0), the attribute "useDefault" will determine if the VM should use
+         * the OS' default audio driver or not. This additional attribute is necessary in order to be backwards compatible
+         * with older VBox versions. */
+        bool fUseDefault = false;
+        if (   elmAudioAdapter.getAttributeValue("useDefault", &fUseDefault) /* Overrides "driver" above (if set). */
+            && fUseDefault)
+            aa.driverType = AudioDriverType_Default;
+
+        // now check if this is actually supported on the current host platform;
+        // people might be opening a file created on a Windows host, and that
+        // VM should still start on a Linux host
+        if (!isAudioDriverAllowedOnThisHost(aa.driverType))
+            aa.driverType = getHostDefaultAudioDriver();
+    }
+}
+
+/**
+ * Called from MachineConfigFile::readHardware() to read guest property information.
+ * @param elmGuestProperties
+ * @param hw
+ */
+void MachineConfigFile::readGuestProperties(const xml::ElementNode &elmGuestProperties,
+                                            Hardware &hw)
+{
+    xml::NodesLoop nl1(elmGuestProperties, "GuestProperty");
+    const xml::ElementNode *pelmProp;
+    while ((pelmProp = nl1.forAllNodes()))
+    {
+        GuestProperty prop;
+
+        pelmProp->getAttributeValue("name", prop.strName);
+        pelmProp->getAttributeValue("value", prop.strValue);
+
+        pelmProp->getAttributeValue("timestamp", prop.timestamp);
+        pelmProp->getAttributeValue("flags", prop.strFlags);
+
+        /* Check guest property 'name' and 'value' for correctness before
+         * placing it to local cache. */
+
+        int vrc = GuestPropValidateName(prop.strName.c_str(), prop.strName.length() + 1  /* '\0' */);
+        if (RT_FAILURE(vrc))
+        {
+            LogRel(("WARNING: Guest property with invalid name (%s) present in VM configuration file. Guest property will be dropped.\n",
+                    prop.strName.c_str()));
+            continue;
+        }
+
+        vrc = GuestPropValidateValue(prop.strValue.c_str(), prop.strValue.length() + 1  /* '\0' */);
+        if (vrc == VERR_TOO_MUCH_DATA)
+        {
+            LogRel(("WARNING: Guest property '%s' present in VM configuration file and has too long value. Guest property value will be truncated.\n",
+                    prop.strName.c_str()));
+
+            /* In order to pass validation, guest property value length (including '\0') in bytes
+             * should be less than GUEST_PROP_MAX_VALUE_LEN. Chop it down to an appropriate length. */
+            prop.strValue.truncate(GUEST_PROP_MAX_VALUE_LEN - 1 /*terminator*/);
+        }
+        else if (RT_FAILURE(vrc))
+        {
+            LogRel(("WARNING: Guest property '%s' present in VM configuration file and has invalid value. Guest property will be dropped.\n",
+                    prop.strName.c_str()));
+            continue;
+        }
+
+        hw.llGuestProperties.push_back(prop);
+    }
+}
+
+/**
+ * Helper function to read attributes that are common to \<SATAController\> (pre-1.7)
+ * and \<StorageController\>.
+ * @param elmStorageController
+ * @param sctl
+ */
+void MachineConfigFile::readStorageControllerAttributes(const xml::ElementNode &elmStorageController,
+                                                        StorageController &sctl)
+{
+    elmStorageController.getAttributeValue("PortCount", sctl.ulPortCount);
+    elmStorageController.getAttributeValue("useHostIOCache", sctl.fUseHostIOCache);
+}
+
+/**
+ * Reads in a \<Hardware\> block and stores it in the given structure. Used
+ * both directly from readMachine and from readSnapshot, since snapshots
+ * have their own hardware sections.
+ *
+ * For legacy pre-1.7 settings we also need a storage structure because
+ * the IDE and SATA controllers used to be defined under \<Hardware\>.
+ *
+ * @param elmHardware           Hardware node to read from.
+ * @param hw                    Where to store the hardware settings.
+ */
+void MachineConfigFile::readHardware(const xml::ElementNode &elmHardware,
+                                     Hardware &hw)
+{
+    if (m->sv >= SettingsVersion_v1_16)
+    {
+        /* Starting with VirtualBox 5.1 the default is Default, before it was
+         * Legacy. This needs to matched by areParavirtDefaultSettings(). */
+        hw.paravirtProvider = ParavirtProvider_Default;
+        /* The new default is disabled, before it was enabled by default. */
+        hw.vrdeSettings.fEnabled = false;
+        /* The new default is disabled, before it was enabled by default. */
+        hw.audioAdapter.fEnabled = false;
+    }
+
+    if (m->sv >= SettingsVersion_v1_17)
+    {
+        /* Starting with VirtualBox 5.2 the default is disabled, before it was
+         * enabled. This needs to matched by AudioAdapter::areDefaultSettings(). */
+        hw.audioAdapter.fEnabledIn = false;
+        /* The new default is disabled, before it was enabled by default. */
+        hw.audioAdapter.fEnabledOut = false;
+    }
+
+    if (!elmHardware.getAttributeValue("version", hw.strVersion))
+    {
+        /* KLUDGE ALERT!  For a while during the 3.1 development this was not
+           written because it was thought to have a default value of "2".  For
+           sv <= 1.3 it defaults to "1" because the attribute didn't exist,
+           while for 1.4+ it is sort of mandatory.  Now, the buggy XML writer
+           code only wrote 1.7 and later.  So, if it's a 1.7+ XML file and it's
+           missing the hardware version, then it probably should be "2" instead
+           of "1". */
+        if (m->sv < SettingsVersion_v1_7)
+            hw.strVersion = "1";
+        else
+            hw.strVersion = "2";
+    }
+    Utf8Str strUUID;
+    if (elmHardware.getAttributeValue("uuid", strUUID))
+        parseUUID(hw.uuid, strUUID, &elmHardware);
+
+    xml::NodesLoop nl1(elmHardware);
+    const xml::ElementNode *pelmHwChild;
+    while ((pelmHwChild = nl1.forAllNodes()))
+    {
+        if (pelmHwChild->nameEquals("CPU"))
+        {
+            if (!pelmHwChild->getAttributeValue("count", hw.cCPUs))
+            {
+                // pre-1.5 variant; not sure if this actually exists in the wild anywhere
+                const xml::ElementNode *pelmCPUChild;
+                if ((pelmCPUChild = pelmHwChild->findChildElement("CPUCount")))
+                    pelmCPUChild->getAttributeValue("count", hw.cCPUs);
+            }
+
+            pelmHwChild->getAttributeValue("hotplug", hw.fCpuHotPlug);
+            pelmHwChild->getAttributeValue("executionCap", hw.ulCpuExecutionCap);
+
+            const xml::ElementNode *pelmCPUChild;
+            if (hw.fCpuHotPlug)
+            {
+                if ((pelmCPUChild = pelmHwChild->findChildElement("CpuTree")))
+                    readCpuTree(*pelmCPUChild, hw.llCpus);
+            }
+
+            if ((pelmCPUChild = pelmHwChild->findChildElement("HardwareVirtEx")))
+            {
+                pelmCPUChild->getAttributeValue("enabled", hw.fHardwareVirt);
+            }
+            if ((pelmCPUChild = pelmHwChild->findChildElement("HardwareVirtExNestedPaging")))
+                pelmCPUChild->getAttributeValue("enabled", hw.fNestedPaging);
+            if ((pelmCPUChild = pelmHwChild->findChildElement("HardwareVirtExLargePages")))
+                pelmCPUChild->getAttributeValue("enabled", hw.fLargePages);
+            if ((pelmCPUChild = pelmHwChild->findChildElement("HardwareVirtExVPID")))
+                pelmCPUChild->getAttributeValue("enabled", hw.fVPID);
+            if ((pelmCPUChild = pelmHwChild->findChildElement("HardwareVirtExUX")))
+                pelmCPUChild->getAttributeValue("enabled", hw.fUnrestrictedExecution);
+            if ((pelmCPUChild = pelmHwChild->findChildElement("HardwareVirtForce")))
+                pelmCPUChild->getAttributeValue("enabled", hw.fHardwareVirtForce);
+            if ((pelmCPUChild = pelmHwChild->findChildElement("HardwareVirtExUseNativeApi")))
+                pelmCPUChild->getAttributeValue("enabled", hw.fUseNativeApi);
+            if ((pelmCPUChild = pelmHwChild->findChildElement("HardwareVirtExVirtVmsaveVmload")))
+                pelmCPUChild->getAttributeValue("enabled", hw.fVirtVmsaveVmload);
+
+            if (!(pelmCPUChild = pelmHwChild->findChildElement("PAE")))
+            {
+                /* The default for pre 3.1 was false, so we must respect that. */
+                if (m->sv < SettingsVersion_v1_9)
+                    hw.fPAE = false;
+            }
+            else
+                pelmCPUChild->getAttributeValue("enabled", hw.fPAE);
+
+            bool fLongMode;
+            if (   (pelmCPUChild = pelmHwChild->findChildElement("LongMode"))
+                && pelmCPUChild->getAttributeValue("enabled", fLongMode) )
+                hw.enmLongMode = fLongMode ? Hardware::LongMode_Enabled : Hardware::LongMode_Disabled;
+            else
+                hw.enmLongMode = Hardware::LongMode_Legacy;
+
+            if ((pelmCPUChild = pelmHwChild->findChildElement("SyntheticCpu")))
+            {
+                bool fSyntheticCpu = false;
+                pelmCPUChild->getAttributeValue("enabled", fSyntheticCpu);
+                hw.uCpuIdPortabilityLevel = fSyntheticCpu ? 1 : 0;
+            }
+            pelmHwChild->getAttributeValue("CpuIdPortabilityLevel", hw.uCpuIdPortabilityLevel);
+            pelmHwChild->getAttributeValue("CpuProfile", hw.strCpuProfile);
+
+            if ((pelmCPUChild = pelmHwChild->findChildElement("TripleFaultReset")))
+                pelmCPUChild->getAttributeValue("enabled", hw.fTripleFaultReset);
+
+            if ((pelmCPUChild = pelmHwChild->findChildElement("APIC")))
+                pelmCPUChild->getAttributeValue("enabled", hw.fAPIC);
+            if ((pelmCPUChild = pelmHwChild->findChildElement("X2APIC")))
+                pelmCPUChild->getAttributeValue("enabled", hw.fX2APIC);
+            if (hw.fX2APIC)
+                hw.fAPIC = true;
+            pelmCPUChild = pelmHwChild->findChildElement("IBPBOn");
+            if (pelmCPUChild)
+            {
+                pelmCPUChild->getAttributeValue("vmexit", hw.fIBPBOnVMExit);
+                pelmCPUChild->getAttributeValue("vmentry", hw.fIBPBOnVMEntry);
+            }
+            pelmCPUChild = pelmHwChild->findChildElement("SpecCtrl");
+            if (pelmCPUChild)
+                pelmCPUChild->getAttributeValue("enabled", hw.fSpecCtrl);
+            pelmCPUChild = pelmHwChild->findChildElement("SpecCtrlByHost");
+            if (pelmCPUChild)
+                pelmCPUChild->getAttributeValue("enabled", hw.fSpecCtrlByHost);
+            pelmCPUChild = pelmHwChild->findChildElement("L1DFlushOn");
+            if (pelmCPUChild)
+            {
+                pelmCPUChild->getAttributeValue("scheduling", hw.fL1DFlushOnSched);
+                pelmCPUChild->getAttributeValue("vmentry", hw.fL1DFlushOnVMEntry);
+            }
+            pelmCPUChild = pelmHwChild->findChildElement("MDSClearOn");
+            if (pelmCPUChild)
+            {
+                pelmCPUChild->getAttributeValue("scheduling", hw.fMDSClearOnSched);
+                pelmCPUChild->getAttributeValue("vmentry", hw.fMDSClearOnVMEntry);
+            }
+            pelmCPUChild = pelmHwChild->findChildElement("NestedHWVirt");
+            if (pelmCPUChild)
+                pelmCPUChild->getAttributeValue("enabled", hw.fNestedHWVirt);
+
+            if ((pelmCPUChild = pelmHwChild->findChildElement("CpuIdTree")))
+                readCpuIdTree(*pelmCPUChild, hw.llCpuIdLeafs);
+        }
+        else if (pelmHwChild->nameEquals("Memory"))
+        {
+            pelmHwChild->getAttributeValue("RAMSize", hw.ulMemorySizeMB);
+            pelmHwChild->getAttributeValue("PageFusion", hw.fPageFusionEnabled);
+        }
+        else if (pelmHwChild->nameEquals("Firmware"))
+        {
+            Utf8Str strFirmwareType;
+            if (pelmHwChild->getAttributeValue("type", strFirmwareType))
+            {
+                if (    (strFirmwareType == "BIOS")
+                     || (strFirmwareType == "1")                // some trunk builds used the number here
+                   )
+                    hw.firmwareType = FirmwareType_BIOS;
+                else if (    (strFirmwareType == "EFI")
+                          || (strFirmwareType == "2")           // some trunk builds used the number here
+                        )
+                    hw.firmwareType = FirmwareType_EFI;
+                else if (    strFirmwareType == "EFI32")
+                    hw.firmwareType = FirmwareType_EFI32;
+                else if (    strFirmwareType == "EFI64")
+                    hw.firmwareType = FirmwareType_EFI64;
+                else if (    strFirmwareType == "EFIDUAL")
+                    hw.firmwareType = FirmwareType_EFIDUAL;
+                else
+                    throw ConfigFileError(this,
+                                          pelmHwChild,
+                                          N_("Invalid value '%s' in Firmware/@type"),
+                                          strFirmwareType.c_str());
+            }
+        }
+        else if (pelmHwChild->nameEquals("HID"))
+        {
+            Utf8Str strHIDType;
+            if (pelmHwChild->getAttributeValue("Keyboard", strHIDType))
+            {
+                if (strHIDType == "None")
+                    hw.keyboardHIDType = KeyboardHIDType_None;
+                else if (strHIDType == "USBKeyboard")
+                    hw.keyboardHIDType = KeyboardHIDType_USBKeyboard;
+                else if (strHIDType == "PS2Keyboard")
+                    hw.keyboardHIDType = KeyboardHIDType_PS2Keyboard;
+                else if (strHIDType == "ComboKeyboard")
+                    hw.keyboardHIDType = KeyboardHIDType_ComboKeyboard;
+                else
+                    throw ConfigFileError(this,
+                                          pelmHwChild,
+                                          N_("Invalid value '%s' in HID/Keyboard/@type"),
+                                          strHIDType.c_str());
+            }
+            if (pelmHwChild->getAttributeValue("Pointing", strHIDType))
+            {
+                 if (strHIDType == "None")
+                    hw.pointingHIDType = PointingHIDType_None;
+                else if (strHIDType == "USBMouse")
+                    hw.pointingHIDType = PointingHIDType_USBMouse;
+                else if (strHIDType == "USBTablet")
+                    hw.pointingHIDType = PointingHIDType_USBTablet;
+                else if (strHIDType == "PS2Mouse")
+                    hw.pointingHIDType = PointingHIDType_PS2Mouse;
+                else if (strHIDType == "ComboMouse")
+                    hw.pointingHIDType = PointingHIDType_ComboMouse;
+                else if (strHIDType == "USBMultiTouch")
+                    hw.pointingHIDType = PointingHIDType_USBMultiTouch;
+                else if (strHIDType == "USBMTScreenPlusPad")
+                    hw.pointingHIDType = PointingHIDType_USBMultiTouchScreenPlusPad;
+                else
+                    throw ConfigFileError(this,
+                                          pelmHwChild,
+                                          N_("Invalid value '%s' in HID/Pointing/@type"),
+                                          strHIDType.c_str());
+            }
+        }
+        else if (pelmHwChild->nameEquals("Chipset"))
+        {
+            Utf8Str strChipsetType;
+            if (pelmHwChild->getAttributeValue("type", strChipsetType))
+            {
+                if (strChipsetType == "PIIX3")
+                    hw.chipsetType = ChipsetType_PIIX3;
+                else if (strChipsetType == "ICH9")
+                    hw.chipsetType = ChipsetType_ICH9;
+                else
+                    throw ConfigFileError(this,
+                                          pelmHwChild,
+                                          N_("Invalid value '%s' in Chipset/@type"),
+                                          strChipsetType.c_str());
+            }
+        }
+        else if (pelmHwChild->nameEquals("Iommu"))
+        {
+            Utf8Str strIommuType;
+            if (pelmHwChild->getAttributeValue("type", strIommuType))
+            {
+                if (strIommuType == "None")
+                    hw.iommuType = IommuType_None;
+                else if (strIommuType == "Automatic")
+                    hw.iommuType = IommuType_Automatic;
+                else if (strIommuType == "AMD")
+                    hw.iommuType = IommuType_AMD;
+                else if (strIommuType == "Intel")
+                    hw.iommuType = IommuType_Intel;
+                else
+                    throw ConfigFileError(this,
+                                          pelmHwChild,
+                                          N_("Invalid value '%s' in Iommu/@type"),
+                                          strIommuType.c_str());
+            }
+        }
+        else if (pelmHwChild->nameEquals("Paravirt"))
+        {
+            Utf8Str strProvider;
+            if (pelmHwChild->getAttributeValue("provider", strProvider))
+            {
+                if (strProvider == "None")
+                    hw.paravirtProvider = ParavirtProvider_None;
+                else if (strProvider == "Default")
+                    hw.paravirtProvider = ParavirtProvider_Default;
+                else if (strProvider == "Legacy")
+                    hw.paravirtProvider = ParavirtProvider_Legacy;
+                else if (strProvider == "Minimal")
+                    hw.paravirtProvider = ParavirtProvider_Minimal;
+                else if (strProvider == "HyperV")
+                    hw.paravirtProvider = ParavirtProvider_HyperV;
+                else if (strProvider == "KVM")
+                    hw.paravirtProvider = ParavirtProvider_KVM;
+                else
+                    throw ConfigFileError(this,
+                                          pelmHwChild,
+                                          N_("Invalid value '%s' in Paravirt/@provider attribute"),
+                                          strProvider.c_str());
+            }
+
+            pelmHwChild->getAttributeValue("debug", hw.strParavirtDebug);
+        }
+        else if (pelmHwChild->nameEquals("HPET"))
+        {
+            pelmHwChild->getAttributeValue("enabled", hw.fHPETEnabled);
+        }
+        else if (pelmHwChild->nameEquals("Boot"))
+        {
+            hw.mapBootOrder.clear();
+
+            xml::NodesLoop nl2(*pelmHwChild, "Order");
+            const xml::ElementNode *pelmOrder;
+            while ((pelmOrder = nl2.forAllNodes()))
+            {
+                uint32_t ulPos;
+                Utf8Str strDevice;
+                if (!pelmOrder->getAttributeValue("position", ulPos))
+                    throw ConfigFileError(this, pelmOrder, N_("Required Boot/Order/@position attribute is missing"));
+
+                if (    ulPos < 1
+                     || ulPos > SchemaDefs::MaxBootPosition
+                   )
+                    throw ConfigFileError(this,
+                                          pelmOrder,
+                                          N_("Invalid value '%RU32' in Boot/Order/@position: must be greater than 0 and less than %RU32"),
+                                          ulPos,
+                                          SchemaDefs::MaxBootPosition + 1);
+                // XML is 1-based but internal data is 0-based
+                --ulPos;
+
+                if (hw.mapBootOrder.find(ulPos) != hw.mapBootOrder.end())
+                    throw ConfigFileError(this, pelmOrder, N_("Invalid value '%RU32' in Boot/Order/@position: value is not unique"), ulPos);
+
+                if (!pelmOrder->getAttributeValue("device", strDevice))
+                    throw ConfigFileError(this, pelmOrder, N_("Required Boot/Order/@device attribute is missing"));
+
+                DeviceType_T type;
+                if (strDevice == "None")
+                    type = DeviceType_Null;
+                else if (strDevice == "Floppy")
+                    type = DeviceType_Floppy;
+                else if (strDevice == "DVD")
+                    type = DeviceType_DVD;
+                else if (strDevice == "HardDisk")
+                    type = DeviceType_HardDisk;
+                else if (strDevice == "Network")
+                    type = DeviceType_Network;
+                else
+                    throw ConfigFileError(this, pelmOrder, N_("Invalid value '%s' in Boot/Order/@device attribute"), strDevice.c_str());
+                hw.mapBootOrder[ulPos] = type;
+            }
+        }
+        else if (pelmHwChild->nameEquals("Display"))
+        {
+            Utf8Str strGraphicsControllerType;
+            if (!pelmHwChild->getAttributeValue("controller", strGraphicsControllerType))
+                hw.graphicsAdapter.graphicsControllerType = GraphicsControllerType_VBoxVGA;
+            else
+            {
+                strGraphicsControllerType.toUpper();
+                GraphicsControllerType_T type;
+                if (strGraphicsControllerType == "VBOXVGA")
+                    type = GraphicsControllerType_VBoxVGA;
+                else if (strGraphicsControllerType == "VMSVGA")
+                    type = GraphicsControllerType_VMSVGA;
+                else if (strGraphicsControllerType == "VBOXSVGA")
+                    type = GraphicsControllerType_VBoxSVGA;
+                else if (strGraphicsControllerType == "NONE")
+                    type = GraphicsControllerType_Null;
+                else
+                    throw ConfigFileError(this, pelmHwChild, N_("Invalid value '%s' in Display/@controller attribute"), strGraphicsControllerType.c_str());
+                hw.graphicsAdapter.graphicsControllerType = type;
+            }
+            pelmHwChild->getAttributeValue("VRAMSize", hw.graphicsAdapter.ulVRAMSizeMB);
+            if (!pelmHwChild->getAttributeValue("monitorCount", hw.graphicsAdapter.cMonitors))
+                pelmHwChild->getAttributeValue("MonitorCount", hw.graphicsAdapter.cMonitors);       // pre-v1.5 variant
+            if (!pelmHwChild->getAttributeValue("accelerate3D", hw.graphicsAdapter.fAccelerate3D))
+                pelmHwChild->getAttributeValue("Accelerate3D", hw.graphicsAdapter.fAccelerate3D);   // pre-v1.5 variant
+            pelmHwChild->getAttributeValue("accelerate2DVideo", hw.graphicsAdapter.fAccelerate2DVideo);
+        }
+        else if (pelmHwChild->nameEquals("RemoteDisplay"))
+        {
+            pelmHwChild->getAttributeValue("enabled", hw.vrdeSettings.fEnabled);
+
+            Utf8Str str;
+            if (pelmHwChild->getAttributeValue("port", str))
+                hw.vrdeSettings.mapProperties["TCP/Ports"] = str;
+            if (pelmHwChild->getAttributeValue("netAddress", str))
+                hw.vrdeSettings.mapProperties["TCP/Address"] = str;
+
+            Utf8Str strAuthType;
+            if (pelmHwChild->getAttributeValue("authType", strAuthType))
+            {
+                // settings before 1.3 used lower case so make sure this is case-insensitive
+                strAuthType.toUpper();
+                if (strAuthType == "NULL")
+                    hw.vrdeSettings.authType = AuthType_Null;
+                else if (strAuthType == "GUEST")
+                    hw.vrdeSettings.authType = AuthType_Guest;
+                else if (strAuthType == "EXTERNAL")
+                    hw.vrdeSettings.authType = AuthType_External;
+                else
+                    throw ConfigFileError(this, pelmHwChild, N_("Invalid value '%s' in RemoteDisplay/@authType attribute"), strAuthType.c_str());
+            }
+
+            pelmHwChild->getAttributeValue("authLibrary", hw.vrdeSettings.strAuthLibrary);
+            pelmHwChild->getAttributeValue("authTimeout", hw.vrdeSettings.ulAuthTimeout);
+            pelmHwChild->getAttributeValue("allowMultiConnection", hw.vrdeSettings.fAllowMultiConnection);
+            pelmHwChild->getAttributeValue("reuseSingleConnection", hw.vrdeSettings.fReuseSingleConnection);
+
+            /* 3.2 and 4.0 betas, 4.0 has this information in VRDEProperties. */
+            const xml::ElementNode *pelmVideoChannel;
+            if ((pelmVideoChannel = pelmHwChild->findChildElement("VideoChannel")))
+            {
+                bool fVideoChannel = false;
+                pelmVideoChannel->getAttributeValue("enabled", fVideoChannel);
+                hw.vrdeSettings.mapProperties["VideoChannel/Enabled"] = fVideoChannel? "true": "false";
+
+                uint32_t ulVideoChannelQuality = 75;
+                pelmVideoChannel->getAttributeValue("quality", ulVideoChannelQuality);
+                ulVideoChannelQuality = RT_CLAMP(ulVideoChannelQuality, 10, 100);
+                char *pszBuffer = NULL;
+                if (RTStrAPrintf(&pszBuffer, "%d", ulVideoChannelQuality) >= 0)
+                {
+                    hw.vrdeSettings.mapProperties["VideoChannel/Quality"] = pszBuffer;
+                    RTStrFree(pszBuffer);
+                }
+                else
+                    hw.vrdeSettings.mapProperties["VideoChannel/Quality"] = "75";
+            }
+            pelmHwChild->getAttributeValue("VRDEExtPack", hw.vrdeSettings.strVrdeExtPack);
+
+            const xml::ElementNode *pelmProperties = pelmHwChild->findChildElement("VRDEProperties");
+            if (pelmProperties != NULL)
+            {
+                xml::NodesLoop nl(*pelmProperties);
+                const xml::ElementNode *pelmProperty;
+                while ((pelmProperty = nl.forAllNodes()))
+                {
+                    if (pelmProperty->nameEquals("Property"))
+                    {
+                        /* <Property name="TCP/Ports" value="3000-3002"/> */
+                        Utf8Str strName, strValue;
+                        if (   pelmProperty->getAttributeValue("name", strName)
+                            && pelmProperty->getAttributeValue("value", strValue))
+                            hw.vrdeSettings.mapProperties[strName] = strValue;
+                        else
+                            throw ConfigFileError(this, pelmProperty, N_("Required VRDE Property/@name or @value attribute is missing"));
+                    }
+                }
+            }
+        }
+        else if (pelmHwChild->nameEquals("BIOS"))
+        {
+            const xml::ElementNode *pelmBIOSChild;
+            if ((pelmBIOSChild = pelmHwChild->findChildElement("ACPI")))
+                pelmBIOSChild->getAttributeValue("enabled", hw.biosSettings.fACPIEnabled);
+            if ((pelmBIOSChild = pelmHwChild->findChildElement("IOAPIC")))
+                pelmBIOSChild->getAttributeValue("enabled", hw.biosSettings.fIOAPICEnabled);
+            if ((pelmBIOSChild = pelmHwChild->findChildElement("APIC")))
+            {
+                Utf8Str strAPIC;
+                if (pelmBIOSChild->getAttributeValue("mode", strAPIC))
+                {
+                    strAPIC.toUpper();
+                    if (strAPIC == "DISABLED")
+                        hw.biosSettings.apicMode = APICMode_Disabled;
+                    else if (strAPIC == "APIC")
+                        hw.biosSettings.apicMode = APICMode_APIC;
+                    else if (strAPIC == "X2APIC")
+                        hw.biosSettings.apicMode = APICMode_X2APIC;
+                    else
+                        throw ConfigFileError(this, pelmBIOSChild, N_("Invalid value '%s' in APIC/@mode attribute"), strAPIC.c_str());
+                }
+            }
+            if ((pelmBIOSChild = pelmHwChild->findChildElement("Logo")))
+            {
+                pelmBIOSChild->getAttributeValue("fadeIn", hw.biosSettings.fLogoFadeIn);
+                pelmBIOSChild->getAttributeValue("fadeOut", hw.biosSettings.fLogoFadeOut);
+                pelmBIOSChild->getAttributeValue("displayTime", hw.biosSettings.ulLogoDisplayTime);
+                pelmBIOSChild->getAttributeValue("imagePath", hw.biosSettings.strLogoImagePath);
+            }
+            if ((pelmBIOSChild = pelmHwChild->findChildElement("BootMenu")))
+            {
+                Utf8Str strBootMenuMode;
+                if (pelmBIOSChild->getAttributeValue("mode", strBootMenuMode))
+                {
+                    // settings before 1.3 used lower case so make sure this is case-insensitive
+                    strBootMenuMode.toUpper();
+                    if (strBootMenuMode == "DISABLED")
+                        hw.biosSettings.biosBootMenuMode = BIOSBootMenuMode_Disabled;
+                    else if (strBootMenuMode == "MENUONLY")
+                        hw.biosSettings.biosBootMenuMode = BIOSBootMenuMode_MenuOnly;
+                    else if (strBootMenuMode == "MESSAGEANDMENU")
+                        hw.biosSettings.biosBootMenuMode = BIOSBootMenuMode_MessageAndMenu;
+                    else
+                        throw ConfigFileError(this, pelmBIOSChild, N_("Invalid value '%s' in BootMenu/@mode attribute"), strBootMenuMode.c_str());
+                }
+            }
+            if ((pelmBIOSChild = pelmHwChild->findChildElement("PXEDebug")))
+                pelmBIOSChild->getAttributeValue("enabled", hw.biosSettings.fPXEDebugEnabled);
+            if ((pelmBIOSChild = pelmHwChild->findChildElement("TimeOffset")))
+                pelmBIOSChild->getAttributeValue("value", hw.biosSettings.llTimeOffset);
+            if ((pelmBIOSChild = pelmHwChild->findChildElement("NVRAM")))
+            {
+                pelmBIOSChild->getAttributeValue("path", hw.nvramSettings.strNvramPath);
+                if (m->sv >= SettingsVersion_v1_19)
+                {
+                    pelmBIOSChild->getAttributeValue("keyId", hw.nvramSettings.strKeyId);
+                    pelmBIOSChild->getAttributeValue("keyStore", hw.nvramSettings.strKeyStore);
+                }
+            }
+            if ((pelmBIOSChild = pelmHwChild->findChildElement("SmbiosUuidLittleEndian")))
+                pelmBIOSChild->getAttributeValue("enabled", hw.biosSettings.fSmbiosUuidLittleEndian);
+            else
+                hw.biosSettings.fSmbiosUuidLittleEndian = false; /* Default for existing VMs. */
+
+            // legacy BIOS/IDEController (pre 1.7)
+            if (    (m->sv < SettingsVersion_v1_7)
+                 && (pelmBIOSChild = pelmHwChild->findChildElement("IDEController"))
+               )
+            {
+                StorageController sctl;
+                sctl.strName = "IDE Controller";
+                sctl.storageBus = StorageBus_IDE;
+
+                Utf8Str strType;
+                if (pelmBIOSChild->getAttributeValue("type", strType))
+                {
+                    if (strType == "PIIX3")
+                        sctl.controllerType = StorageControllerType_PIIX3;
+                    else if (strType == "PIIX4")
+                        sctl.controllerType = StorageControllerType_PIIX4;
+                    else if (strType == "ICH6")
+                        sctl.controllerType = StorageControllerType_ICH6;
+                    else
+                        throw ConfigFileError(this, pelmBIOSChild, N_("Invalid value '%s' for IDEController/@type attribute"), strType.c_str());
+                }
+                sctl.ulPortCount = 2;
+                hw.storage.llStorageControllers.push_back(sctl);
+            }
+        }
+        else if (pelmHwChild->nameEquals("TrustedPlatformModule"))
+        {
+            Utf8Str strTpmType;
+            if (pelmHwChild->getAttributeValue("type", strTpmType))
+            {
+                if (strTpmType == "None")
+                    hw.tpmSettings.tpmType = TpmType_None;
+                else if (strTpmType == "v1_2")
+                    hw.tpmSettings.tpmType = TpmType_v1_2;
+                else if (strTpmType == "v2_0")
+                    hw.tpmSettings.tpmType = TpmType_v2_0;
+                else if (strTpmType == "Host")
+                    hw.tpmSettings.tpmType = TpmType_Host;
+                else if (strTpmType == "Swtpm")
+                    hw.tpmSettings.tpmType = TpmType_Swtpm;
+                else
+                    throw ConfigFileError(this,
+                                          pelmHwChild,
+                                          N_("Invalid value '%s' in TrustedPlatformModule/@type"),
+                                          strTpmType.c_str());
+            }
+
+            pelmHwChild->getAttributeValue("location", hw.tpmSettings.strLocation);
+        }
+        else if (   (m->sv <= SettingsVersion_v1_14)
+                 && pelmHwChild->nameEquals("USBController"))
+        {
+            bool fEnabled = false;
+
+            pelmHwChild->getAttributeValue("enabled", fEnabled);
+            if (fEnabled)
+            {
+                /* Create OHCI controller with default name. */
+                USBController ctrl;
+
+                ctrl.strName = "OHCI";
+                ctrl.enmType = USBControllerType_OHCI;
+                hw.usbSettings.llUSBControllers.push_back(ctrl);
+            }
+
+            pelmHwChild->getAttributeValue("enabledEhci", fEnabled);
+            if (fEnabled)
+            {
+                /* Create OHCI controller with default name. */
+                USBController ctrl;
+
+                ctrl.strName = "EHCI";
+                ctrl.enmType = USBControllerType_EHCI;
+                hw.usbSettings.llUSBControllers.push_back(ctrl);
+            }
+
+            readUSBDeviceFilters(*pelmHwChild,
+                                 hw.usbSettings.llDeviceFilters);
+        }
+        else if (pelmHwChild->nameEquals("USB"))
+        {
+            const xml::ElementNode *pelmUSBChild;
+
+            if ((pelmUSBChild = pelmHwChild->findChildElement("Controllers")))
+            {
+                xml::NodesLoop nl2(*pelmUSBChild, "Controller");
+                const xml::ElementNode *pelmCtrl;
+
+                while ((pelmCtrl = nl2.forAllNodes()))
+                {
+                    USBController ctrl;
+                    com::Utf8Str strCtrlType;
+
+                    pelmCtrl->getAttributeValue("name", ctrl.strName);
+
+                    if (pelmCtrl->getAttributeValue("type", strCtrlType))
+                    {
+                        if (strCtrlType == "OHCI")
+                            ctrl.enmType = USBControllerType_OHCI;
+                        else if (strCtrlType == "EHCI")
+                            ctrl.enmType = USBControllerType_EHCI;
+                        else if (strCtrlType == "XHCI")
+                            ctrl.enmType = USBControllerType_XHCI;
+                        else
+                            throw ConfigFileError(this, pelmCtrl, N_("Invalid value '%s' for Controller/@type attribute"), strCtrlType.c_str());
+                    }
+
+                    hw.usbSettings.llUSBControllers.push_back(ctrl);
+                }
+            }
+
+            if ((pelmUSBChild = pelmHwChild->findChildElement("DeviceFilters")))
+                readUSBDeviceFilters(*pelmUSBChild, hw.usbSettings.llDeviceFilters);
+        }
+        else if (   m->sv < SettingsVersion_v1_7
+                 && pelmHwChild->nameEquals("SATAController"))
+        {
+            bool f;
+            if (   pelmHwChild->getAttributeValue("enabled", f)
+                && f)
+            {
+                StorageController sctl;
+                sctl.strName = "SATA Controller";
+                sctl.storageBus = StorageBus_SATA;
+                sctl.controllerType = StorageControllerType_IntelAhci;
+
+                readStorageControllerAttributes(*pelmHwChild, sctl);
+
+                hw.storage.llStorageControllers.push_back(sctl);
+            }
+        }
+        else if (pelmHwChild->nameEquals("Network"))
+            readNetworkAdapters(*pelmHwChild, hw.llNetworkAdapters);
+        else if (pelmHwChild->nameEquals("RTC"))
+        {
+            Utf8Str strLocalOrUTC;
+            machineUserData.fRTCUseUTC = pelmHwChild->getAttributeValue("localOrUTC", strLocalOrUTC)
+                                      && strLocalOrUTC == "UTC";
+        }
+        else if (    pelmHwChild->nameEquals("UART")
+                  || pelmHwChild->nameEquals("Uart")      // used before 1.3
+                )
+            readSerialPorts(*pelmHwChild, hw.llSerialPorts);
+        else if (    pelmHwChild->nameEquals("LPT")
+                  || pelmHwChild->nameEquals("Lpt")       // used before 1.3
+                )
+            readParallelPorts(*pelmHwChild, hw.llParallelPorts);
+        else if (pelmHwChild->nameEquals("AudioAdapter"))
+            readAudioAdapter(*pelmHwChild, hw.audioAdapter);
+        else if (pelmHwChild->nameEquals("SharedFolders"))
+        {
+            xml::NodesLoop nl2(*pelmHwChild, "SharedFolder");
+            const xml::ElementNode *pelmFolder;
+            while ((pelmFolder = nl2.forAllNodes()))
+            {
+                SharedFolder sf;
+                pelmFolder->getAttributeValue("name", sf.strName);
+                pelmFolder->getAttributeValue("hostPath", sf.strHostPath);
+                pelmFolder->getAttributeValue("writable", sf.fWritable);
+                pelmFolder->getAttributeValue("autoMount", sf.fAutoMount);
+                pelmFolder->getAttributeValue("autoMountPoint", sf.strAutoMountPoint);
+                hw.llSharedFolders.push_back(sf);
+            }
+        }
+        else if (pelmHwChild->nameEquals("Clipboard"))
+        {
+            Utf8Str strTemp;
+            if (pelmHwChild->getAttributeValue("mode", strTemp))
+            {
+                if (strTemp == "Disabled")
+                    hw.clipboardMode = ClipboardMode_Disabled;
+                else if (strTemp == "HostToGuest")
+                    hw.clipboardMode = ClipboardMode_HostToGuest;
+                else if (strTemp == "GuestToHost")
+                    hw.clipboardMode = ClipboardMode_GuestToHost;
+                else if (strTemp == "Bidirectional")
+                    hw.clipboardMode = ClipboardMode_Bidirectional;
+                else
+                    throw ConfigFileError(this, pelmHwChild, N_("Invalid value '%s' in Clipboard/@mode attribute"), strTemp.c_str());
+            }
+
+            pelmHwChild->getAttributeValue("fileTransfersEnabled", hw.fClipboardFileTransfersEnabled);
+        }
+        else if (pelmHwChild->nameEquals("DragAndDrop"))
+        {
+            Utf8Str strTemp;
+            if (pelmHwChild->getAttributeValue("mode", strTemp))
+            {
+                if (strTemp == "Disabled")
+                    hw.dndMode = DnDMode_Disabled;
+                else if (strTemp == "HostToGuest")
+                    hw.dndMode = DnDMode_HostToGuest;
+                else if (strTemp == "GuestToHost")
+                    hw.dndMode = DnDMode_GuestToHost;
+                else if (strTemp == "Bidirectional")
+                    hw.dndMode = DnDMode_Bidirectional;
+                else
+                    throw ConfigFileError(this, pelmHwChild, N_("Invalid value '%s' in DragAndDrop/@mode attribute"), strTemp.c_str());
+            }
+        }
+        else if (pelmHwChild->nameEquals("Guest"))
+        {
+            if (!pelmHwChild->getAttributeValue("memoryBalloonSize", hw.ulMemoryBalloonSize))
+                pelmHwChild->getAttributeValue("MemoryBalloonSize", hw.ulMemoryBalloonSize);            // used before 1.3
+        }
+        else if (pelmHwChild->nameEquals("GuestProperties"))
+            readGuestProperties(*pelmHwChild, hw);
+        else if (pelmHwChild->nameEquals("IO"))
+        {
+            const xml::ElementNode *pelmBwGroups;
+            const xml::ElementNode *pelmIOChild;
+
+            if ((pelmIOChild = pelmHwChild->findChildElement("IoCache")))
+            {
+                pelmIOChild->getAttributeValue("enabled", hw.ioSettings.fIOCacheEnabled);
+                pelmIOChild->getAttributeValue("size", hw.ioSettings.ulIOCacheSize);
+            }
+
+            if ((pelmBwGroups = pelmHwChild->findChildElement("BandwidthGroups")))
+            {
+                xml::NodesLoop nl2(*pelmBwGroups, "BandwidthGroup");
+                const xml::ElementNode *pelmBandwidthGroup;
+                while ((pelmBandwidthGroup = nl2.forAllNodes()))
+                {
+                    BandwidthGroup gr;
+                    Utf8Str strTemp;
+
+                    pelmBandwidthGroup->getAttributeValue("name", gr.strName);
+
+                    if (pelmBandwidthGroup->getAttributeValue("type", strTemp))
+                    {
+                        if (strTemp == "Disk")
+                            gr.enmType = BandwidthGroupType_Disk;
+                        else if (strTemp == "Network")
+                            gr.enmType = BandwidthGroupType_Network;
+                        else
+                            throw ConfigFileError(this, pelmBandwidthGroup, N_("Invalid value '%s' in BandwidthGroup/@type attribute"), strTemp.c_str());
+                    }
+                    else
+                        throw ConfigFileError(this, pelmBandwidthGroup, N_("Missing BandwidthGroup/@type attribute"));
+
+                    if (!pelmBandwidthGroup->getAttributeValue("maxBytesPerSec", gr.cMaxBytesPerSec))
+                    {
+                        pelmBandwidthGroup->getAttributeValue("maxMbPerSec", gr.cMaxBytesPerSec);
+                        gr.cMaxBytesPerSec *= _1M;
+                    }
+                    hw.ioSettings.llBandwidthGroups.push_back(gr);
+                }
+            }
+        }
+        else if (pelmHwChild->nameEquals("HostPci"))
+        {
+            const xml::ElementNode *pelmDevices;
+
+            if ((pelmDevices = pelmHwChild->findChildElement("Devices")))
+            {
+                xml::NodesLoop nl2(*pelmDevices, "Device");
+                const xml::ElementNode *pelmDevice;
+                while ((pelmDevice = nl2.forAllNodes()))
+                {
+                    HostPCIDeviceAttachment hpda;
+
+                    if (!pelmDevice->getAttributeValue("host", hpda.uHostAddress))
+                         throw ConfigFileError(this, pelmDevice, N_("Missing Device/@host attribute"));
+
+                    if (!pelmDevice->getAttributeValue("guest", hpda.uGuestAddress))
+                         throw ConfigFileError(this, pelmDevice, N_("Missing Device/@guest attribute"));
+
+                    /* name is optional */
+                    pelmDevice->getAttributeValue("name", hpda.strDeviceName);
+
+                    hw.pciAttachments.push_back(hpda);
+                }
+            }
+        }
+        else if (pelmHwChild->nameEquals("EmulatedUSB"))
+        {
+            const xml::ElementNode *pelmCardReader;
+
+            if ((pelmCardReader = pelmHwChild->findChildElement("CardReader")))
+            {
+                pelmCardReader->getAttributeValue("enabled", hw.fEmulatedUSBCardReader);
+            }
+        }
+        else if (pelmHwChild->nameEquals("Frontend"))
+        {
+            const xml::ElementNode *pelmDefault;
+
+            if ((pelmDefault = pelmHwChild->findChildElement("Default")))
+            {
+                pelmDefault->getAttributeValue("type", hw.strDefaultFrontend);
+            }
+        }
+        else if (pelmHwChild->nameEquals("StorageControllers"))
+            readStorageControllers(*pelmHwChild, hw.storage);
+    }
+
+    if (hw.ulMemorySizeMB == (uint32_t)-1)
+        throw ConfigFileError(this, &elmHardware, N_("Required Memory/@RAMSize element/attribute is missing"));
+}
+
+/**
+ * This gets called instead of readStorageControllers() for legacy pre-1.7 settings
+ * files which have a \<HardDiskAttachments\> node and storage controller settings
+ * hidden in the \<Hardware\> settings. We set the StorageControllers fields just the
+ * same, just from different sources.
+ * @param elmHardDiskAttachments  \<HardDiskAttachments\> XML node.
+ * @param strg
+ */
+void MachineConfigFile::readHardDiskAttachments_pre1_7(const xml::ElementNode &elmHardDiskAttachments,
+                                                       Storage &strg)
+{
+    StorageController *pIDEController = NULL;
+    StorageController *pSATAController = NULL;
+
+    for (StorageControllersList::iterator it = strg.llStorageControllers.begin();
+         it != strg.llStorageControllers.end();
+         ++it)
+    {
+        StorageController &s = *it;
+        if (s.storageBus == StorageBus_IDE)
+            pIDEController = &s;
+        else if (s.storageBus == StorageBus_SATA)
+            pSATAController = &s;
+    }
+
+    xml::NodesLoop nl1(elmHardDiskAttachments, "HardDiskAttachment");
+    const xml::ElementNode *pelmAttachment;
+    while ((pelmAttachment = nl1.forAllNodes()))
+    {
+        AttachedDevice att;
+        Utf8Str strUUID, strBus;
+
+        if (!pelmAttachment->getAttributeValue("hardDisk", strUUID))
+            throw ConfigFileError(this, pelmAttachment, N_("Required HardDiskAttachment/@hardDisk attribute is missing"));
+        parseUUID(att.uuid, strUUID, pelmAttachment);
+
+        if (!pelmAttachment->getAttributeValue("bus", strBus))
+            throw ConfigFileError(this, pelmAttachment, N_("Required HardDiskAttachment/@bus attribute is missing"));
+        // pre-1.7 'channel' is now port
+        if (!pelmAttachment->getAttributeValue("channel", att.lPort))
+            throw ConfigFileError(this, pelmAttachment, N_("Required HardDiskAttachment/@channel attribute is missing"));
+        // pre-1.7 'device' is still device
+        if (!pelmAttachment->getAttributeValue("device", att.lDevice))
+            throw ConfigFileError(this, pelmAttachment, N_("Required HardDiskAttachment/@device attribute is missing"));
+
+        att.deviceType = DeviceType_HardDisk;
+
+        if (strBus == "IDE")
+        {
+            if (!pIDEController)
+                throw ConfigFileError(this, pelmAttachment, N_("HardDiskAttachment/@bus is 'IDE' but cannot find IDE controller"));
+            pIDEController->llAttachedDevices.push_back(att);
+        }
+        else if (strBus == "SATA")
+        {
+            if (!pSATAController)
+                throw ConfigFileError(this, pelmAttachment, N_("HardDiskAttachment/@bus is 'SATA' but cannot find SATA controller"));
+            pSATAController->llAttachedDevices.push_back(att);
+        }
+        else
+            throw ConfigFileError(this, pelmAttachment, N_("HardDiskAttachment/@bus attribute has illegal value '%s'"), strBus.c_str());
+    }
+}
+
+/**
+ * Reads in a \<StorageControllers\> block and stores it in the given Storage structure.
+ * Used both directly from readMachine and from readSnapshot, since snapshots
+ * have their own storage controllers sections.
+ *
+ * This is only called for settings version 1.7 and above; see readHardDiskAttachments_pre1_7()
+ * for earlier versions.
+ *
+ * @param   elmStorageControllers
+ * @param   strg
+ */
+void MachineConfigFile::readStorageControllers(const xml::ElementNode &elmStorageControllers,
+                                               Storage &strg)
+{
+    xml::NodesLoop nlStorageControllers(elmStorageControllers, "StorageController");
+    const xml::ElementNode *pelmController;
+    while ((pelmController = nlStorageControllers.forAllNodes()))
+    {
+        StorageController sctl;
+
+        if (!pelmController->getAttributeValue("name", sctl.strName))
+            throw ConfigFileError(this, pelmController, N_("Required StorageController/@name attribute is missing"));
+        //  canonicalize storage controller names for configs in the switchover
+        //  period.
+        if (m->sv < SettingsVersion_v1_9)
+        {
+            if (sctl.strName == "IDE")
+                sctl.strName = "IDE Controller";
+            else if (sctl.strName == "SATA")
+                sctl.strName = "SATA Controller";
+            else if (sctl.strName == "SCSI")
+                sctl.strName = "SCSI Controller";
+        }
+
+        pelmController->getAttributeValue("Instance", sctl.ulInstance);
+            // default from constructor is 0
+
+        pelmController->getAttributeValue("Bootable", sctl.fBootable);
+            // default from constructor is true which is true
+            // for settings below version 1.11 because they allowed only
+            // one controller per type.
+
+        Utf8Str strType;
+        if (!pelmController->getAttributeValue("type", strType))
+            throw ConfigFileError(this, pelmController, N_("Required StorageController/@type attribute is missing"));
+
+        if (strType == "AHCI")
+        {
+            sctl.storageBus = StorageBus_SATA;
+            sctl.controllerType = StorageControllerType_IntelAhci;
+        }
+        else if (strType == "LsiLogic")
+        {
+            sctl.storageBus = StorageBus_SCSI;
+            sctl.controllerType = StorageControllerType_LsiLogic;
+        }
+        else if (strType == "BusLogic")
+        {
+            sctl.storageBus = StorageBus_SCSI;
+            sctl.controllerType = StorageControllerType_BusLogic;
+        }
+        else if (strType == "PIIX3")
+        {
+            sctl.storageBus = StorageBus_IDE;
+            sctl.controllerType = StorageControllerType_PIIX3;
+        }
+        else if (strType == "PIIX4")
+        {
+            sctl.storageBus = StorageBus_IDE;
+            sctl.controllerType = StorageControllerType_PIIX4;
+        }
+        else if (strType == "ICH6")
+        {
+            sctl.storageBus = StorageBus_IDE;
+            sctl.controllerType = StorageControllerType_ICH6;
+        }
+        else if (   (m->sv >= SettingsVersion_v1_9)
+                 && (strType == "I82078")
+                )
+        {
+            sctl.storageBus = StorageBus_Floppy;
+            sctl.controllerType = StorageControllerType_I82078;
+        }
+        else if (strType == "LsiLogicSas")
+        {
+            sctl.storageBus = StorageBus_SAS;
+            sctl.controllerType = StorageControllerType_LsiLogicSas;
+        }
+        else if (strType == "USB")
+        {
+            sctl.storageBus = StorageBus_USB;
+            sctl.controllerType = StorageControllerType_USB;
+        }
+        else if (strType == "NVMe")
+        {
+            sctl.storageBus = StorageBus_PCIe;
+            sctl.controllerType = StorageControllerType_NVMe;
+        }
+        else if (strType == "VirtioSCSI")
+        {
+            sctl.storageBus = StorageBus_VirtioSCSI;
+            sctl.controllerType = StorageControllerType_VirtioSCSI;
+        }
+        else
+            throw ConfigFileError(this, pelmController, N_("Invalid value '%s' for StorageController/@type attribute"), strType.c_str());
+
+        readStorageControllerAttributes(*pelmController, sctl);
+
+        xml::NodesLoop nlAttached(*pelmController, "AttachedDevice");
+        const xml::ElementNode *pelmAttached;
+        while ((pelmAttached = nlAttached.forAllNodes()))
+        {
+            AttachedDevice att;
+            Utf8Str strTemp;
+            pelmAttached->getAttributeValue("type", strTemp);
+
+            att.fDiscard = false;
+            att.fNonRotational = false;
+            att.fHotPluggable = false;
+            att.fPassThrough = false;
+
+            if (strTemp == "HardDisk")
+            {
+                att.deviceType = DeviceType_HardDisk;
+                pelmAttached->getAttributeValue("nonrotational", att.fNonRotational);
+                pelmAttached->getAttributeValue("discard", att.fDiscard);
+            }
+            else if (m->sv >= SettingsVersion_v1_9)
+            {
+                // starting with 1.9 we list DVD and floppy drive info + attachments under <StorageControllers>
+                if (strTemp == "DVD")
+                {
+                    att.deviceType = DeviceType_DVD;
+                    pelmAttached->getAttributeValue("passthrough", att.fPassThrough);
+                    pelmAttached->getAttributeValue("tempeject", att.fTempEject);
+                }
+                else if (strTemp == "Floppy")
+                    att.deviceType = DeviceType_Floppy;
+            }
+
+            if (att.deviceType != DeviceType_Null)
+            {
+                const xml::ElementNode *pelmImage;
+                // all types can have images attached, but for HardDisk it's required
+                if (!(pelmImage = pelmAttached->findChildElement("Image")))
+                {
+                    if (att.deviceType == DeviceType_HardDisk)
+                        throw ConfigFileError(this, pelmImage, N_("Required AttachedDevice/Image element is missing"));
+                    else
+                    {
+                        // DVDs and floppies can also have <HostDrive> instead of <Image>
+                        const xml::ElementNode *pelmHostDrive;
+                        if ((pelmHostDrive = pelmAttached->findChildElement("HostDrive")))
+                            if (!pelmHostDrive->getAttributeValue("src", att.strHostDriveSrc))
+                                throw ConfigFileError(this, pelmHostDrive, N_("Required AttachedDevice/HostDrive/@src attribute is missing"));
+                    }
+                }
+                else
+                {
+                    if (!pelmImage->getAttributeValue("uuid", strTemp))
+                        throw ConfigFileError(this, pelmImage, N_("Required AttachedDevice/Image/@uuid attribute is missing"));
+                    parseUUID(att.uuid, strTemp, pelmImage);
+                }
+
+                if (!pelmAttached->getAttributeValue("port", att.lPort))
+                    throw ConfigFileError(this, pelmImage, N_("Required AttachedDevice/@port attribute is missing"));
+                if (!pelmAttached->getAttributeValue("device", att.lDevice))
+                    throw ConfigFileError(this, pelmImage, N_("Required AttachedDevice/@device attribute is missing"));
+
+                /* AHCI controller ports are hotpluggable by default, keep compatibility with existing settings. */
+                if (m->sv >= SettingsVersion_v1_15)
+                    pelmAttached->getAttributeValue("hotpluggable", att.fHotPluggable);
+                else if (sctl.controllerType == StorageControllerType_IntelAhci)
+                    att.fHotPluggable = true;
+
+                pelmAttached->getAttributeValue("bandwidthGroup", att.strBwGroup);
+                sctl.llAttachedDevices.push_back(att);
+            }
+        }
+
+        strg.llStorageControllers.push_back(sctl);
+    }
+}
+
+/**
+ * This gets called for legacy pre-1.9 settings files after having parsed the
+ * \<Hardware\> and \<StorageControllers\> sections to parse \<Hardware\> once more
+ * for the \<DVDDrive\> and \<FloppyDrive\> sections.
+ *
+ * Before settings version 1.9, DVD and floppy drives were specified separately
+ * under \<Hardware\>; we then need this extra loop to make sure the storage
+ * controller structs are already set up so we can add stuff to them.
+ *
+ * @param elmHardware
+ * @param strg
+ */
+void MachineConfigFile::readDVDAndFloppies_pre1_9(const xml::ElementNode &elmHardware,
+                                                  Storage &strg)
+{
+    xml::NodesLoop nl1(elmHardware);
+    const xml::ElementNode *pelmHwChild;
+    while ((pelmHwChild = nl1.forAllNodes()))
+    {
+        if (pelmHwChild->nameEquals("DVDDrive"))
+        {
+            // create a DVD "attached device" and attach it to the existing IDE controller
+            AttachedDevice att;
+            att.deviceType = DeviceType_DVD;
+            // legacy DVD drive is always secondary master (port 1, device 0)
+            att.lPort = 1;
+            att.lDevice = 0;
+            pelmHwChild->getAttributeValue("passthrough", att.fPassThrough);
+            pelmHwChild->getAttributeValue("tempeject", att.fTempEject);
+
+            const xml::ElementNode *pDriveChild;
+            Utf8Str strTmp;
+            if (   (pDriveChild = pelmHwChild->findChildElement("Image")) != NULL
+                && pDriveChild->getAttributeValue("uuid", strTmp))
+                parseUUID(att.uuid, strTmp, pDriveChild);
+            else if ((pDriveChild = pelmHwChild->findChildElement("HostDrive")))
+                pDriveChild->getAttributeValue("src", att.strHostDriveSrc);
+
+            // find the IDE controller and attach the DVD drive
+            bool fFound = false;
+            for (StorageControllersList::iterator it = strg.llStorageControllers.begin();
+                 it != strg.llStorageControllers.end();
+                 ++it)
+            {
+                StorageController &sctl = *it;
+                if (sctl.storageBus == StorageBus_IDE)
+                {
+                    sctl.llAttachedDevices.push_back(att);
+                    fFound = true;
+                    break;
+                }
+            }
+
+            if (!fFound)
+                throw ConfigFileError(this, pelmHwChild, N_("Internal error: found DVD drive but IDE controller does not exist"));
+                        // shouldn't happen because pre-1.9 settings files always had at least one IDE controller in the settings
+                        // which should have gotten parsed in <StorageControllers> before this got called
+        }
+        else if (pelmHwChild->nameEquals("FloppyDrive"))
+        {
+            bool fEnabled;
+            if (   pelmHwChild->getAttributeValue("enabled", fEnabled)
+                && fEnabled)
+            {
+                // create a new floppy controller and attach a floppy "attached device"
+                StorageController sctl;
+                sctl.strName = "Floppy Controller";
+                sctl.storageBus = StorageBus_Floppy;
+                sctl.controllerType = StorageControllerType_I82078;
+                sctl.ulPortCount = 1;
+
+                AttachedDevice att;
+                att.deviceType = DeviceType_Floppy;
+                att.lPort = 0;
+                att.lDevice = 0;
+
+                const xml::ElementNode *pDriveChild;
+                Utf8Str strTmp;
+                if (   (pDriveChild = pelmHwChild->findChildElement("Image"))
+                    && pDriveChild->getAttributeValue("uuid", strTmp) )
+                    parseUUID(att.uuid, strTmp, pDriveChild);
+                else if ((pDriveChild = pelmHwChild->findChildElement("HostDrive")))
+                    pDriveChild->getAttributeValue("src", att.strHostDriveSrc);
+
+                // store attachment with controller
+                sctl.llAttachedDevices.push_back(att);
+                // store controller with storage
+                strg.llStorageControllers.push_back(sctl);
+            }
+        }
+    }
+}
+
+/**
+ * Called for reading the \<Teleporter\> element under \<Machine\>.
+ */
+void MachineConfigFile::readTeleporter(const xml::ElementNode &elmTeleporter,
+                                       MachineUserData &userData)
+{
+    elmTeleporter.getAttributeValue("enabled", userData.fTeleporterEnabled);
+    elmTeleporter.getAttributeValue("port", userData.uTeleporterPort);
+    elmTeleporter.getAttributeValue("address", userData.strTeleporterAddress);
+    elmTeleporter.getAttributeValue("password", userData.strTeleporterPassword);
+
+    if (   userData.strTeleporterPassword.isNotEmpty()
+        && !VBoxIsPasswordHashed(&userData.strTeleporterPassword))
+        VBoxHashPassword(&userData.strTeleporterPassword);
+}
+
+/**
+ * Called for reading the \<Debugging\> element under \<Machine\> or \<Snapshot\>.
+ */
+void MachineConfigFile::readDebugging(const xml::ElementNode &elmDebugging, Debugging &dbg)
+{
+    if (m->sv < SettingsVersion_v1_13)
+        return;
+
+    const xml::ElementNode *pelmTracing = elmDebugging.findChildElement("Tracing");
+    if (pelmTracing)
+    {
+        pelmTracing->getAttributeValue("enabled", dbg.fTracingEnabled);
+        pelmTracing->getAttributeValue("allowTracingToAccessVM", dbg.fAllowTracingToAccessVM);
+        pelmTracing->getAttributeValue("config", dbg.strTracingConfig);
+    }
+
+    const xml::ElementNode *pelmGuestDebug = elmDebugging.findChildElement("GuestDebug");
+    if (pelmGuestDebug)
+    {
+        Utf8Str strTmp;
+        pelmGuestDebug->getAttributeValue("provider", strTmp);
+        if (strTmp == "None")
+            dbg.enmDbgProvider = GuestDebugProvider_None;
+        else if (strTmp == "GDB")
+            dbg.enmDbgProvider = GuestDebugProvider_GDB;
+        else if (strTmp == "KD")
+            dbg.enmDbgProvider = GuestDebugProvider_KD;
+        else
+            throw ConfigFileError(this, pelmGuestDebug, N_("Invalid value '%s' for GuestDebug/@provider attribute"), strTmp.c_str());
+
+        pelmGuestDebug->getAttributeValue("io", strTmp);
+        if (strTmp == "None")
+            dbg.enmIoProvider = GuestDebugIoProvider_None;
+        else if (strTmp == "TCP")
+            dbg.enmIoProvider = GuestDebugIoProvider_TCP;
+        else if (strTmp == "UDP")
+            dbg.enmIoProvider = GuestDebugIoProvider_UDP;
+        else if (strTmp == "IPC")
+            dbg.enmIoProvider = GuestDebugIoProvider_IPC;
+        else
+            throw ConfigFileError(this, pelmGuestDebug, N_("Invalid value '%s' for GuestDebug/@io attribute"), strTmp.c_str());
+
+        pelmGuestDebug->getAttributeValue("address", dbg.strAddress);
+        pelmGuestDebug->getAttributeValue("port", dbg.ulPort);
+    }
+}
+
+/**
+ * Called for reading the \<Autostart\> element under \<Machine\> or \<Snapshot\>.
+ */
+void MachineConfigFile::readAutostart(const xml::ElementNode &elmAutostart, Autostart &autostrt)
+{
+    Utf8Str strAutostop;
+
+    if (m->sv < SettingsVersion_v1_13)
+        return;
+
+    elmAutostart.getAttributeValue("enabled", autostrt.fAutostartEnabled);
+    elmAutostart.getAttributeValue("delay", autostrt.uAutostartDelay);
+    elmAutostart.getAttributeValue("autostop", strAutostop);
+    if (strAutostop == "Disabled")
+        autostrt.enmAutostopType = AutostopType_Disabled;
+    else if (strAutostop == "SaveState")
+        autostrt.enmAutostopType = AutostopType_SaveState;
+    else if (strAutostop == "PowerOff")
+        autostrt.enmAutostopType = AutostopType_PowerOff;
+    else if (strAutostop == "AcpiShutdown")
+        autostrt.enmAutostopType = AutostopType_AcpiShutdown;
+    else
+        throw ConfigFileError(this, &elmAutostart, N_("Invalid value '%s' for Autostart/@autostop attribute"), strAutostop.c_str());
+}
+
+/**
+ * Called for reading the \<VideoCapture\> element under \<Machine|Hardware\>,
+ * or \<Recording\> under \<Machine\>,
+ */
+void MachineConfigFile::readRecordingSettings(const xml::ElementNode &elmRecording, uint32_t cMonitors, RecordingSettings &recording)
+{
+    if (cMonitors > 64)
+        throw ConfigFileError(this, &elmRecording, N_("Invalid monitor count given"));
+
+    elmRecording.getAttributeValue("enabled", recording.common.fEnabled);
+
+    /* Note: Since settings 1.19 the recording settings have a dedicated XML branch "Recording" outside of "Hardware". */
+    if (m->sv >= SettingsVersion_v1_19 /* VBox >= 7.0 */)
+    {
+        uint32_t cScreens = 0;
+        elmRecording.getAttributeValue("screens",   cScreens);
+
+        xml::ElementNodesList plstScreens;
+        elmRecording.getChildElements(plstScreens, "Screen");
+
+        /* Sanity checks. */
+        if (cScreens != plstScreens.size())
+            throw ConfigFileError(this, &elmRecording, N_("Recording/@screens attribute does not match stored screen objects"));
+        if (cScreens > 64)
+            throw ConfigFileError(this, &elmRecording, N_("Recording/@screens attribute is invalid"));
+
+        for (xml::ElementNodesList::iterator itScreen  = plstScreens.begin();
+                                             itScreen != plstScreens.end();
+                                           ++itScreen)
+        {
+            /* The screen's stored ID is the monitor ID and also the key for the map. */
+            uint32_t idxScreen;
+            (*itScreen)->getAttributeValue("id",        idxScreen);
+
+            RecordingScreenSettings &screenSettings = recording.mapScreens[idxScreen];
+
+            (*itScreen)->getAttributeValue("enabled",   screenSettings.fEnabled);
+            Utf8Str strTemp;
+            (*itScreen)->getAttributeValue("featuresEnabled", strTemp);
+            RecordingScreenSettings::featuresFromString(strTemp, screenSettings.featureMap);
+            (*itScreen)->getAttributeValue("maxTimeS",  screenSettings.ulMaxTimeS);
+            (*itScreen)->getAttributeValue("options",   screenSettings.strOptions);
+            (*itScreen)->getAttributeValue("dest",      (uint32_t &)screenSettings.enmDest);
+            if (screenSettings.enmDest == RecordingDestination_File)
+                (*itScreen)->getAttributeValuePath("file",  screenSettings.File.strName);
+            else
+                throw ConfigFileError(this, (*itScreen),
+                                      N_("Not supported Recording/@dest attribute '%#x'"), screenSettings.enmDest);
+            (*itScreen)->getAttributeValue("maxSizeMB", screenSettings.File.ulMaxSizeMB);
+            if ((*itScreen)->getAttributeValue("videoCodec", strTemp)) /* Stick with default if not set. */
+                RecordingScreenSettings::videoCodecFromString(strTemp, screenSettings.Video.enmCodec);
+            (*itScreen)->getAttributeValue("videoDeadline", (uint32_t &)screenSettings.Video.enmDeadline);
+            (*itScreen)->getAttributeValue("videoRateCtlMode", (uint32_t &)screenSettings.Video.enmRateCtlMode);
+            (*itScreen)->getAttributeValue("videoScalingMode", (uint32_t &)screenSettings.Video.enmScalingMode);
+            (*itScreen)->getAttributeValue("horzRes",       screenSettings.Video.ulWidth);
+            (*itScreen)->getAttributeValue("vertRes",       screenSettings.Video.ulHeight);
+            (*itScreen)->getAttributeValue("rateKbps",      screenSettings.Video.ulRate);
+            (*itScreen)->getAttributeValue("fps",           screenSettings.Video.ulFPS);
+
+            if ((*itScreen)->getAttributeValue("audioCodec", strTemp)) /* Stick with default if not set. */
+                RecordingScreenSettings::audioCodecFromString(strTemp, screenSettings.Audio.enmCodec);
+            (*itScreen)->getAttributeValue("audioDeadline", (uint32_t &)screenSettings.Audio.enmDeadline);
+            (*itScreen)->getAttributeValue("audioRateCtlMode", (uint32_t &)screenSettings.Audio.enmRateCtlMode);
+            (*itScreen)->getAttributeValue("audioHz",       (uint32_t &)screenSettings.Audio.uHz);
+            (*itScreen)->getAttributeValue("audioBits",     (uint32_t &)screenSettings.Audio.cBits);
+            (*itScreen)->getAttributeValue("audioChannels", (uint32_t &)screenSettings.Audio.cChannels);
+        }
+    }
+    else if (   m->sv >= SettingsVersion_v1_14
+             && m->sv <  SettingsVersion_v1_19 /* VBox < 7.0 */)
+    {
+        /* For settings < 1.19 (< VBox 7.0) we only support one recording configuration, that is,
+         * all screens have the same configuration. So load/save to/from screen 0. */
+        RecordingScreenSettings &screen0 = recording.mapScreens[0];
+
+        elmRecording.getAttributeValue("maxTime",   screen0.ulMaxTimeS);
+        elmRecording.getAttributeValue("options",   screen0.strOptions);
+        elmRecording.getAttributeValuePath("file",  screen0.File.strName);
+        elmRecording.getAttributeValue("maxSize",   screen0.File.ulMaxSizeMB);
+        elmRecording.getAttributeValue("horzRes",   screen0.Video.ulWidth);
+        elmRecording.getAttributeValue("vertRes",   screen0.Video.ulHeight);
+        elmRecording.getAttributeValue("rate",      screen0.Video.ulRate);
+        elmRecording.getAttributeValue("fps",       screen0.Video.ulFPS);
+
+        /* Convert the enabled screens to the former uint64_t bit array and vice versa. */
+        uint64_t uScreensBitmap = 0;
+        elmRecording.getAttributeValue("screens",   uScreensBitmap);
+
+        /* Note: For settings < 1.19 the "screens" attribute is a bit field for all screens
+         *       which are ENABLED for recording. The settings for recording are for all the same though. */
+        for (unsigned i = 0; i < cMonitors; i++)
+        {
+            /* Apply settings of screen 0 to screen i and enable it. */
+            recording.mapScreens[i] = screen0;
+
+            /* Screen i enabled? */
+            recording.mapScreens[i].idScreen = i;
+            recording.mapScreens[i].fEnabled = RT_BOOL(uScreensBitmap & RT_BIT_64(i));
+        }
+    }
+}
+
+/**
+ * Called for reading the \<Groups\> element under \<Machine\>.
+ */
+void MachineConfigFile::readGroups(const xml::ElementNode &elmGroups, StringsList &llGroups)
+{
+    llGroups.clear();
+    if (m->sv < SettingsVersion_v1_13)
+    {
+        llGroups.push_back("/");
+        return;
+    }
+
+    xml::NodesLoop nlGroups(elmGroups);
+    const xml::ElementNode *pelmGroup;
+    while ((pelmGroup = nlGroups.forAllNodes()))
+    {
+        if (pelmGroup->nameEquals("Group"))
+        {
+            Utf8Str strGroup;
+            if (!pelmGroup->getAttributeValue("name", strGroup))
+                throw ConfigFileError(this, pelmGroup, N_("Required Group/@name attribute is missing"));
+            llGroups.push_back(strGroup);
+        }
+    }
+}
+
+/**
+ * Called initially for the \<Snapshot\> element under \<Machine\>, if present,
+ * to store the snapshot's data into the given Snapshot structure (which is
+ * then the one in the Machine struct). This might process further elements
+ * of the snapshot tree if a \<Snapshots\> (plural) element is found in the
+ * snapshot, which should contain a list of child snapshots; such lists are
+ * maintained in the Snapshot structure.
+ *
+ * @param curSnapshotUuid
+ * @param elmSnapshot
+ * @param snap
+ * @returns true if curSnapshotUuid is in this snapshot subtree, otherwise false
+ */
+bool MachineConfigFile::readSnapshot(const Guid &curSnapshotUuid,
+                                     const xml::ElementNode &elmSnapshot,
+                                     Snapshot &snap)
+{
+    std::list<const xml::ElementNode *> llElementsTodo;
+    llElementsTodo.push_back(&elmSnapshot);
+    std::list<Snapshot *> llSettingsTodo;
+    llSettingsTodo.push_back(&snap);
+    std::list<uint32_t> llDepthsTodo;
+    llDepthsTodo.push_back(1);
+
+    bool foundCurrentSnapshot = false;
+
+    while (llElementsTodo.size() > 0)
+    {
+        const xml::ElementNode *pElement = llElementsTodo.front();
+        llElementsTodo.pop_front();
+        Snapshot *pSnap = llSettingsTodo.front();
+        llSettingsTodo.pop_front();
+        uint32_t depth = llDepthsTodo.front();
+        llDepthsTodo.pop_front();
+
+        if (depth > SETTINGS_SNAPSHOT_DEPTH_MAX)
+            throw ConfigFileError(this, pElement, N_("Maximum snapshot tree depth of %u exceeded"), SETTINGS_SNAPSHOT_DEPTH_MAX);
+
+        Utf8Str strTemp;
+        if (!pElement->getAttributeValue("uuid", strTemp))
+            throw ConfigFileError(this, pElement, N_("Required Snapshot/@uuid attribute is missing"));
+        parseUUID(pSnap->uuid, strTemp, pElement);
+        foundCurrentSnapshot |= (pSnap->uuid == curSnapshotUuid);
+
+        if (!pElement->getAttributeValue("name", pSnap->strName))
+            throw ConfigFileError(this, pElement, N_("Required Snapshot/@name attribute is missing"));
+
+        // 3.1 dev builds added Description as an attribute, read it silently
+        // and write it back as an element
+        pElement->getAttributeValue("Description", pSnap->strDescription);
+
+        if (!pElement->getAttributeValue("timeStamp", strTemp))
+            throw ConfigFileError(this, pElement, N_("Required Snapshot/@timeStamp attribute is missing"));
+        parseTimestamp(pSnap->timestamp, strTemp, pElement);
+
+        pElement->getAttributeValuePath("stateFile", pSnap->strStateFile);      // online snapshots only
+
+        // parse Hardware before the other elements because other things depend on it
+        const xml::ElementNode *pelmHardware;
+        if (!(pelmHardware = pElement->findChildElement("Hardware")))
+            throw ConfigFileError(this, pElement, N_("Required Snapshot/@Hardware element is missing"));
+        readHardware(*pelmHardware, pSnap->hardware);
+
+        const xml::ElementNode *pelmSnapshots = NULL;
+
+        xml::NodesLoop nlSnapshotChildren(*pElement);
+        const xml::ElementNode *pelmSnapshotChild;
+        while ((pelmSnapshotChild = nlSnapshotChildren.forAllNodes()))
+        {
+            if (pelmSnapshotChild->nameEquals("Description"))
+                pSnap->strDescription = pelmSnapshotChild->getValue();
+            else if (   m->sv < SettingsVersion_v1_7
+                    && pelmSnapshotChild->nameEquals("HardDiskAttachments"))
+                readHardDiskAttachments_pre1_7(*pelmSnapshotChild, pSnap->hardware.storage);
+            else if (   m->sv >= SettingsVersion_v1_7
+                    && pelmSnapshotChild->nameEquals("StorageControllers"))
+                readStorageControllers(*pelmSnapshotChild, pSnap->hardware.storage);
+            else if (pelmSnapshotChild->nameEquals("Snapshots"))
+            {
+                if (pelmSnapshots)
+                    throw ConfigFileError(this, pelmSnapshotChild, N_("Just a single Snapshots element is allowed"));
+                pelmSnapshots = pelmSnapshotChild;
+            }
+        }
+
+        if (m->sv < SettingsVersion_v1_9)
+            // go through Hardware once more to repair the settings controller structures
+            // with data from old DVDDrive and FloppyDrive elements
+            readDVDAndFloppies_pre1_9(*pelmHardware, pSnap->hardware.storage);
+
+        const xml::ElementNode *pelmDebugging = elmSnapshot.findChildElement("Debugging"); /** @todo r=andy Shouldn't this be pElement instead of elmSnapshot? Re-visit this! */
+        if (pelmDebugging)
+            readDebugging(*pelmDebugging, pSnap->debugging);
+        const xml::ElementNode *pelmAutostart = elmSnapshot.findChildElement("Autostart"); /** @todo r=andy Ditto. */
+        if (pelmAutostart)
+            readAutostart(*pelmAutostart, pSnap->autostart);
+        if (m->sv < SettingsVersion_v1_19)
+        {
+            const xml::ElementNode *pelmVideoCapture = pElement->findChildElement("VideoCapture");
+            if (pelmVideoCapture)
+                readRecordingSettings(*pelmVideoCapture, pSnap->hardware.graphicsAdapter.cMonitors, pSnap->recordingSettings);
+        }
+        else /* >= VBox 7.0 */
+        {
+            const xml::ElementNode *pelmRecording = pElement->findChildElement("Recording");
+            if (pelmRecording)
+                readRecordingSettings(*pelmRecording, pSnap->hardware.graphicsAdapter.cMonitors, pSnap->recordingSettings);
+        }
+        // note: Groups exist only for Machine, not for Snapshot
+
+        // process all child snapshots
+        if (pelmSnapshots)
+        {
+            xml::NodesLoop nlChildSnapshots(*pelmSnapshots);
+            const xml::ElementNode *pelmChildSnapshot;
+            while ((pelmChildSnapshot = nlChildSnapshots.forAllNodes()))
+            {
+                if (pelmChildSnapshot->nameEquals("Snapshot"))
+                {
+                    llElementsTodo.push_back(pelmChildSnapshot);
+                    pSnap->llChildSnapshots.push_back(Snapshot::Empty);
+                    llSettingsTodo.push_back(&pSnap->llChildSnapshots.back());
+                    llDepthsTodo.push_back(depth + 1);
+                }
+            }
+        }
+    }
+
+    return foundCurrentSnapshot;
+}
+
+const struct {
+    const char *pcszOld;
+    const char *pcszNew;
+} aConvertOSTypes[] =
+{
+    { "unknown", "Other" },
+    { "dos", "DOS" },
+    { "win31", "Windows31" },
+    { "win95", "Windows95" },
+    { "win98", "Windows98" },
+    { "winme", "WindowsMe" },
+    { "winnt4", "WindowsNT4" },
+    { "win2k", "Windows2000" },
+    { "winxp", "WindowsXP" },
+    { "win2k3", "Windows2003" },
+    { "winvista", "WindowsVista" },
+    { "win2k8", "Windows2008" },
+    { "os2warp3", "OS2Warp3" },
+    { "os2warp4", "OS2Warp4" },
+    { "os2warp45", "OS2Warp45" },
+    { "ecs", "OS2eCS" },
+    { "linux22", "Linux22" },
+    { "linux24", "Linux24" },
+    { "linux26", "Linux26" },
+    { "archlinux", "ArchLinux" },
+    { "debian", "Debian" },
+    { "opensuse", "OpenSUSE" },
+    { "fedoracore", "Fedora" },
+    { "gentoo", "Gentoo" },
+    { "mandriva", "Mandriva" },
+    { "redhat", "RedHat" },
+    { "ubuntu", "Ubuntu" },
+    { "xandros", "Xandros" },
+    { "freebsd", "FreeBSD" },
+    { "openbsd", "OpenBSD" },
+    { "netbsd", "NetBSD" },
+    { "netware", "Netware" },
+    { "solaris", "Solaris" },
+    { "opensolaris", "OpenSolaris" },
+    { "l4", "L4" }
+};
+
+void MachineConfigFile::convertOldOSType_pre1_5(Utf8Str &str)
+{
+    for (unsigned u = 0;
+         u < RT_ELEMENTS(aConvertOSTypes);
+         ++u)
+    {
+        if (str == aConvertOSTypes[u].pcszOld)
+        {
+            str = aConvertOSTypes[u].pcszNew;
+            break;
+        }
+    }
+}
+
+/**
+ * Called from the constructor to actually read in the \<Machine\> element
+ * of a machine config file.
+ * @param elmMachine
+ */
+void MachineConfigFile::readMachine(const xml::ElementNode &elmMachine)
+{
+    Utf8Str strUUID;
+    if (   elmMachine.getAttributeValue("uuid", strUUID)
+        && elmMachine.getAttributeValue("name", machineUserData.strName))
+    {
+        parseUUID(uuid, strUUID, &elmMachine);
+
+        elmMachine.getAttributeValue("directoryIncludesUUID", machineUserData.fDirectoryIncludesUUID);
+        elmMachine.getAttributeValue("nameSync", machineUserData.fNameSync);
+
+        Utf8Str str;
+        elmMachine.getAttributeValue("Description", machineUserData.strDescription);
+        elmMachine.getAttributeValue("OSType", machineUserData.strOsType);
+        if (m->sv < SettingsVersion_v1_5)
+            convertOldOSType_pre1_5(machineUserData.strOsType);
+
+        elmMachine.getAttributeValue("stateKeyId", strStateKeyId);
+        elmMachine.getAttributeValue("stateKeyStore", strStateKeyStore);
+        elmMachine.getAttributeValuePath("stateFile", strStateFile);
+
+        elmMachine.getAttributeValue("logKeyId", strLogKeyId);
+        elmMachine.getAttributeValue("logKeyStore", strLogKeyStore);
+
+        if (elmMachine.getAttributeValue("currentSnapshot", str))
+            parseUUID(uuidCurrentSnapshot, str, &elmMachine);
+
+        elmMachine.getAttributeValuePath("snapshotFolder", machineUserData.strSnapshotFolder);
+
+        if (!elmMachine.getAttributeValue("currentStateModified", fCurrentStateModified))
+            fCurrentStateModified = true;
+        if (elmMachine.getAttributeValue("lastStateChange", str))
+            parseTimestamp(timeLastStateChange, str, &elmMachine);
+            // constructor has called RTTimeNow(&timeLastStateChange) before
+        if (elmMachine.getAttributeValue("aborted", fAborted))
+            fAborted = true;
+
+        {
+            Utf8Str strVMPriority;
+            if (elmMachine.getAttributeValue("processPriority", strVMPriority))
+            {
+                if (strVMPriority == "Flat")
+                    machineUserData.enmVMPriority = VMProcPriority_Flat;
+                else if (strVMPriority == "Low")
+                    machineUserData.enmVMPriority = VMProcPriority_Low;
+                else if (strVMPriority == "Normal")
+                    machineUserData.enmVMPriority = VMProcPriority_Normal;
+                else if (strVMPriority == "High")
+                    machineUserData.enmVMPriority = VMProcPriority_High;
+                else
+                    machineUserData.enmVMPriority = VMProcPriority_Default;
+            }
+        }
+
+        str.setNull();
+        elmMachine.getAttributeValue("icon", str);
+        parseBase64(machineUserData.ovIcon, str, &elmMachine);
+
+        // parse Hardware before the other elements because other things depend on it
+        const xml::ElementNode *pelmHardware;
+        if (!(pelmHardware = elmMachine.findChildElement("Hardware")))
+            throw ConfigFileError(this, &elmMachine, N_("Required Machine/Hardware element is missing"));
+        readHardware(*pelmHardware, hardwareMachine);
+
+        xml::NodesLoop nlRootChildren(elmMachine);
+        const xml::ElementNode *pelmMachineChild;
+        while ((pelmMachineChild = nlRootChildren.forAllNodes()))
+        {
+            if (pelmMachineChild->nameEquals("ExtraData"))
+                readExtraData(*pelmMachineChild,
+                              mapExtraDataItems);
+            else if (    (m->sv < SettingsVersion_v1_7)
+                      && (pelmMachineChild->nameEquals("HardDiskAttachments"))
+                    )
+                readHardDiskAttachments_pre1_7(*pelmMachineChild, hardwareMachine.storage);
+            else if (    (m->sv >= SettingsVersion_v1_7)
+                      && (pelmMachineChild->nameEquals("StorageControllers"))
+                    )
+                readStorageControllers(*pelmMachineChild, hardwareMachine.storage);
+            else if (pelmMachineChild->nameEquals("Snapshot"))
+            {
+                if (uuidCurrentSnapshot.isZero())
+                    throw ConfigFileError(this, &elmMachine, N_("Snapshots present but required Machine/@currentSnapshot attribute is missing"));
+                bool foundCurrentSnapshot = false;
+                // Work directly with the target list, because otherwise
+                // the entire snapshot settings tree will need to be copied,
+                // and the usual STL implementation needs a lot of stack space.
+                llFirstSnapshot.push_back(Snapshot::Empty);
+                // this will also read all child snapshots
+                foundCurrentSnapshot = readSnapshot(uuidCurrentSnapshot, *pelmMachineChild, llFirstSnapshot.back());
+                if (!foundCurrentSnapshot)
+                    throw ConfigFileError(this, &elmMachine, N_("Snapshots present but none matches the UUID in the Machine/@currentSnapshot attribute"));
+            }
+            else if (pelmMachineChild->nameEquals("Description"))
+                machineUserData.strDescription = pelmMachineChild->getValue();
+            else if (pelmMachineChild->nameEquals("Teleporter"))
+                readTeleporter(*pelmMachineChild, machineUserData);
+            else if (pelmMachineChild->nameEquals("MediaRegistry"))
+                readMediaRegistry(*pelmMachineChild, mediaRegistry);
+            else if (pelmMachineChild->nameEquals("Debugging"))
+                readDebugging(*pelmMachineChild, debugging);
+            else if (pelmMachineChild->nameEquals("Autostart"))
+                readAutostart(*pelmMachineChild, autostart);
+            else if (pelmMachineChild->nameEquals("Groups"))
+                readGroups(*pelmMachineChild, machineUserData.llGroups);
+
+            if (   m->sv >= SettingsVersion_v1_14
+                && m->sv <  SettingsVersion_v1_19
+                && pelmMachineChild->nameEquals("VideoCapture"))   /* For settings >= 1.14 (< VBox 7.0). */
+                readRecordingSettings(*pelmMachineChild, hardwareMachine.graphicsAdapter.cMonitors, recordingSettings);
+            else if (   m->sv >= SettingsVersion_v1_19
+                     && pelmMachineChild->nameEquals("Recording")) /* Only exists for settings >= 1.19 (VBox 7.0). */
+                readRecordingSettings(*pelmMachineChild, hardwareMachine.graphicsAdapter.cMonitors, recordingSettings);
+        }
+
+        if (m->sv < SettingsVersion_v1_9)
+            // go through Hardware once more to repair the settings controller structures
+            // with data from old DVDDrive and FloppyDrive elements
+            readDVDAndFloppies_pre1_9(*pelmHardware, hardwareMachine.storage);
+    }
+    else
+        throw ConfigFileError(this, &elmMachine, N_("Required Machine/@uuid or @name attributes is missing"));
+}
+
+/**
+ * Called from the constructor to decrypt the machine config and read
+ * data from it.
+ * @param elmMachine
+ * @param pCryptoIf             Pointer to the cryptographic interface.
+ * @param pszPassword           The password to decrypt the config with.
+ */
+void MachineConfigFile::readMachineEncrypted(const xml::ElementNode &elmMachine,
+                                             PCVBOXCRYPTOIF pCryptoIf = NULL,
+                                             const char *pszPassword = NULL)
+{
+    Utf8Str strUUID;
+    if (elmMachine.getAttributeValue("uuid", strUUID))
+    {
+        parseUUID(uuid, strUUID, &elmMachine);
+        if (!elmMachine.getAttributeValue("keyId", strKeyId))
+            throw ConfigFileError(this, &elmMachine, N_("Required MachineEncrypted/@keyId attribute is missing"));
+        if (!elmMachine.getAttributeValue("keyStore", strKeyStore))
+            throw ConfigFileError(this, &elmMachine, N_("Required MachineEncrypted/@keyStore attribute is missing"));
+
+        if (!pszPassword)
+        {
+            enmParseState = ParseState_PasswordError;
+            return;
+        }
+
+        VBOXCRYPTOCTX hCryptoCtx = NULL;
+        int vrc = pCryptoIf->pfnCryptoCtxLoad(strKeyStore.c_str(), pszPassword, &hCryptoCtx);
+        if (RT_SUCCESS(vrc))
+        {
+            com::Utf8Str str = elmMachine.getValue();
+            IconBlob abEncrypted; /** @todo Rename IconBlob because this is not about icons. */
+            /** @todo This is not nice. */
+            try
+            {
+                parseBase64(abEncrypted, str, &elmMachine);
+            }
+            catch (...)
+            {
+                int vrc2 = pCryptoIf->pfnCryptoCtxDestroy(hCryptoCtx);
+                AssertRC(vrc2);
+                throw;
+            }
+
+            IconBlob abDecrypted(abEncrypted.size());
+            size_t cbDecrypted = 0;
+            vrc = pCryptoIf->pfnCryptoCtxDecrypt(hCryptoCtx, false /*fPartial*/,
+                                                 &abEncrypted[0], abEncrypted.size(),
+                                                 uuid.raw(), sizeof(RTUUID),
+                                                 &abDecrypted[0], abDecrypted.size(), &cbDecrypted);
+            int vrc2 = pCryptoIf->pfnCryptoCtxDestroy(hCryptoCtx);
+            AssertRC(vrc2);
+
+            if (RT_SUCCESS(vrc))
+            {
+                abDecrypted.resize(cbDecrypted);
+                xml::XmlMemParser parser;
+                xml::Document *pDoc = new xml::Document;
+                parser.read(&abDecrypted[0], abDecrypted.size(), m->strFilename, *pDoc);
+                xml::ElementNode *pelmRoot = pDoc->getRootElement();
+                if (!pelmRoot || !pelmRoot->nameEquals("Machine"))
+                    throw ConfigFileError(this, pelmRoot, N_("Root element in Machine settings encrypted block must be \"Machine\""));
+                readMachine(*pelmRoot);
+                delete pDoc;
+            }
+        }
+
+        if (RT_FAILURE(vrc))
+        {
+            if (vrc == VERR_ACCESS_DENIED)
+                enmParseState = ParseState_PasswordError;
+            else
+                throw ConfigFileError(this, &elmMachine, N_("Parsing config failed. (%Rrc)"), vrc);
+        }
+    }
+    else
+        throw ConfigFileError(this, &elmMachine, N_("Required MachineEncrypted/@uuid attribute is missing"));
+}
+
+/**
+ * Creates a \<Hardware\> node under elmParent and then writes out the XML
+ * keys under that. Called for both the \<Machine\> node and for snapshots.
+ * @param elmParent
+ * @param hw
+ * @param fl
+ * @param pllElementsWithUuidAttributes
+ */
+void MachineConfigFile::buildHardwareXML(xml::ElementNode &elmParent,
+                                         const Hardware &hw,
+                                         uint32_t fl,
+                                         std::list<xml::ElementNode*> *pllElementsWithUuidAttributes)
+{
+    xml::ElementNode *pelmHardware = elmParent.createChild("Hardware");
+
+    if (   m->sv >= SettingsVersion_v1_4
+        && (m->sv < SettingsVersion_v1_7 ? hw.strVersion != "1" : hw.strVersion != "2"))
+        pelmHardware->setAttribute("version", hw.strVersion);
+
+    if ((m->sv >= SettingsVersion_v1_9)
+         && !hw.uuid.isZero()
+         && hw.uuid.isValid()
+       )
+        pelmHardware->setAttribute("uuid", hw.uuid.toStringCurly());
+
+    xml::ElementNode *pelmCPU      = pelmHardware->createChild("CPU");
+
+    if (!hw.fHardwareVirt)
+        pelmCPU->createChild("HardwareVirtEx")->setAttribute("enabled", hw.fHardwareVirt);
+    if (!hw.fNestedPaging)
+        pelmCPU->createChild("HardwareVirtExNestedPaging")->setAttribute("enabled", hw.fNestedPaging);
+    if (!hw.fVPID)
+        pelmCPU->createChild("HardwareVirtExVPID")->setAttribute("enabled", hw.fVPID);
+    if (!hw.fUnrestrictedExecution)
+        pelmCPU->createChild("HardwareVirtExUX")->setAttribute("enabled", hw.fUnrestrictedExecution);
+    // PAE has too crazy default handling, must always save this setting.
+    pelmCPU->createChild("PAE")->setAttribute("enabled", hw.fPAE);
+    if (m->sv >= SettingsVersion_v1_16)
+    {
+        if (hw.fIBPBOnVMEntry || hw.fIBPBOnVMExit)
+        {
+            xml::ElementNode *pelmChild = pelmCPU->createChild("IBPBOn");
+            if (hw.fIBPBOnVMExit)
+                pelmChild->setAttribute("vmexit", hw.fIBPBOnVMExit);
+            if (hw.fIBPBOnVMEntry)
+                pelmChild->setAttribute("vmentry", hw.fIBPBOnVMEntry);
+        }
+        if (hw.fSpecCtrl)
+            pelmCPU->createChild("SpecCtrl")->setAttribute("enabled", hw.fSpecCtrl);
+        if (hw.fSpecCtrlByHost)
+            pelmCPU->createChild("SpecCtrlByHost")->setAttribute("enabled", hw.fSpecCtrlByHost);
+        if (!hw.fL1DFlushOnSched || hw.fL1DFlushOnVMEntry)
+        {
+            xml::ElementNode *pelmChild = pelmCPU->createChild("L1DFlushOn");
+            if (!hw.fL1DFlushOnSched)
+                pelmChild->setAttribute("scheduling", hw.fL1DFlushOnSched);
+            if (hw.fL1DFlushOnVMEntry)
+                pelmChild->setAttribute("vmentry", hw.fL1DFlushOnVMEntry);
+        }
+        if (!hw.fMDSClearOnSched || hw.fMDSClearOnVMEntry)
+        {
+            xml::ElementNode *pelmChild = pelmCPU->createChild("MDSClearOn");
+            if (!hw.fMDSClearOnSched)
+                pelmChild->setAttribute("scheduling", hw.fMDSClearOnSched);
+            if (hw.fMDSClearOnVMEntry)
+                pelmChild->setAttribute("vmentry", hw.fMDSClearOnVMEntry);
+        }
+    }
+    if (m->sv >= SettingsVersion_v1_17 && hw.fNestedHWVirt)
+        pelmCPU->createChild("NestedHWVirt")->setAttribute("enabled", hw.fNestedHWVirt);
+
+    if (m->sv >= SettingsVersion_v1_18 && !hw.fVirtVmsaveVmload)
+        pelmCPU->createChild("HardwareVirtExVirtVmsaveVmload")->setAttribute("enabled", hw.fVirtVmsaveVmload);
+
+    if (m->sv >= SettingsVersion_v1_14 && hw.enmLongMode != Hardware::LongMode_Legacy)
+    {
+        // LongMode has too crazy default handling, must always save this setting.
+        pelmCPU->createChild("LongMode")->setAttribute("enabled", hw.enmLongMode == Hardware::LongMode_Enabled);
+    }
+
+    if (hw.fTripleFaultReset)
+        pelmCPU->createChild("TripleFaultReset")->setAttribute("enabled", hw.fTripleFaultReset);
+    if (m->sv >= SettingsVersion_v1_14)
+    {
+        if (hw.fX2APIC)
+            pelmCPU->createChild("X2APIC")->setAttribute("enabled", hw.fX2APIC);
+        else if (!hw.fAPIC)
+            pelmCPU->createChild("APIC")->setAttribute("enabled", hw.fAPIC);
+    }
+    if (hw.cCPUs > 1)
+        pelmCPU->setAttribute("count", hw.cCPUs);
+    if (hw.ulCpuExecutionCap != 100)
+        pelmCPU->setAttribute("executionCap", hw.ulCpuExecutionCap);
+    if (hw.uCpuIdPortabilityLevel != 0)
+        pelmCPU->setAttribute("CpuIdPortabilityLevel", hw.uCpuIdPortabilityLevel);
+    if (!hw.strCpuProfile.equals("host") && hw.strCpuProfile.isNotEmpty())
+        pelmCPU->setAttribute("CpuProfile", hw.strCpuProfile);
+
+    // HardwareVirtExLargePages has too crazy default handling, must always save this setting.
+    pelmCPU->createChild("HardwareVirtExLargePages")->setAttribute("enabled", hw.fLargePages);
+
+    if (m->sv >= SettingsVersion_v1_9)
+    {
+        if (hw.fHardwareVirtForce)
+            pelmCPU->createChild("HardwareVirtForce")->setAttribute("enabled", hw.fHardwareVirtForce);
+    }
+
+    if (m->sv >= SettingsVersion_v1_9 && hw.fUseNativeApi)
+        pelmCPU->createChild("HardwareVirtExUseNativeApi")->setAttribute("enabled", hw.fUseNativeApi);
+
+    if (m->sv >= SettingsVersion_v1_10)
+    {
+        if (hw.fCpuHotPlug)
+            pelmCPU->setAttribute("hotplug", hw.fCpuHotPlug);
+
+        xml::ElementNode *pelmCpuTree = NULL;
+        for (CpuList::const_iterator it = hw.llCpus.begin();
+             it != hw.llCpus.end();
+             ++it)
+        {
+            const Cpu &cpu = *it;
+
+            if (pelmCpuTree == NULL)
+                 pelmCpuTree = pelmCPU->createChild("CpuTree");
+
+            xml::ElementNode *pelmCpu = pelmCpuTree->createChild("Cpu");
+            pelmCpu->setAttribute("id", cpu.ulId);
+        }
+    }
+
+    xml::ElementNode *pelmCpuIdTree = NULL;
+    for (CpuIdLeafsList::const_iterator it = hw.llCpuIdLeafs.begin();
+         it != hw.llCpuIdLeafs.end();
+         ++it)
+    {
+        const CpuIdLeaf &leaf = *it;
+
+        if (pelmCpuIdTree == NULL)
+             pelmCpuIdTree = pelmCPU->createChild("CpuIdTree");
+
+        xml::ElementNode *pelmCpuIdLeaf = pelmCpuIdTree->createChild("CpuIdLeaf");
+        pelmCpuIdLeaf->setAttribute("id",  leaf.idx);
+        if (leaf.idxSub != 0)
+            pelmCpuIdLeaf->setAttribute("subleaf",  leaf.idxSub);
+        pelmCpuIdLeaf->setAttribute("eax", leaf.uEax);
+        pelmCpuIdLeaf->setAttribute("ebx", leaf.uEbx);
+        pelmCpuIdLeaf->setAttribute("ecx", leaf.uEcx);
+        pelmCpuIdLeaf->setAttribute("edx", leaf.uEdx);
+    }
+
+    xml::ElementNode *pelmMemory = pelmHardware->createChild("Memory");
+    pelmMemory->setAttribute("RAMSize", hw.ulMemorySizeMB);
+    if (m->sv >= SettingsVersion_v1_10)
+    {
+        if (hw.fPageFusionEnabled)
+            pelmMemory->setAttribute("PageFusion", hw.fPageFusionEnabled);
+    }
+
+    if (    (m->sv >= SettingsVersion_v1_9)
+         && (hw.firmwareType >= FirmwareType_EFI)
+       )
+    {
+        xml::ElementNode *pelmFirmware = pelmHardware->createChild("Firmware");
+        const char *pcszFirmware;
+
+        switch (hw.firmwareType)
+        {
+            case FirmwareType_EFI:      pcszFirmware = "EFI";     break;
+            case FirmwareType_EFI32:    pcszFirmware = "EFI32";   break;
+            case FirmwareType_EFI64:    pcszFirmware = "EFI64";   break;
+            case FirmwareType_EFIDUAL:  pcszFirmware = "EFIDUAL"; break;
+            default:                    pcszFirmware = "None";    break;
+        }
+        pelmFirmware->setAttribute("type", pcszFirmware);
+    }
+
+    if (   m->sv >= SettingsVersion_v1_10
+        && (   hw.pointingHIDType != PointingHIDType_PS2Mouse
+            || hw.keyboardHIDType != KeyboardHIDType_PS2Keyboard))
+    {
+        xml::ElementNode *pelmHID = pelmHardware->createChild("HID");
+        const char *pcszHID;
+
+        if (hw.pointingHIDType != PointingHIDType_PS2Mouse)
+        {
+            switch (hw.pointingHIDType)
+            {
+                case PointingHIDType_USBMouse:      pcszHID = "USBMouse";     break;
+                case PointingHIDType_USBTablet:     pcszHID = "USBTablet";    break;
+                case PointingHIDType_PS2Mouse:      pcszHID = "PS2Mouse";     break;
+                case PointingHIDType_ComboMouse:    pcszHID = "ComboMouse";   break;
+                case PointingHIDType_USBMultiTouch: pcszHID = "USBMultiTouch";break;
+                case PointingHIDType_USBMultiTouchScreenPlusPad: pcszHID = "USBMTScreenPlusPad";break;
+                case PointingHIDType_None:          pcszHID = "None";         break;
+                default:            Assert(false);  pcszHID = "PS2Mouse";     break;
+            }
+            pelmHID->setAttribute("Pointing", pcszHID);
+        }
+
+        if (hw.keyboardHIDType != KeyboardHIDType_PS2Keyboard)
+        {
+            switch (hw.keyboardHIDType)
+            {
+                case KeyboardHIDType_USBKeyboard:   pcszHID = "USBKeyboard";   break;
+                case KeyboardHIDType_PS2Keyboard:   pcszHID = "PS2Keyboard";   break;
+                case KeyboardHIDType_ComboKeyboard: pcszHID = "ComboKeyboard"; break;
+                case KeyboardHIDType_None:          pcszHID = "None";          break;
+                default:            Assert(false);  pcszHID = "PS2Keyboard";   break;
+            }
+            pelmHID->setAttribute("Keyboard", pcszHID);
+        }
+    }
+
+    if (    (m->sv >= SettingsVersion_v1_10)
+        &&  hw.fHPETEnabled
+       )
+    {
+        xml::ElementNode *pelmHPET = pelmHardware->createChild("HPET");
+        pelmHPET->setAttribute("enabled", hw.fHPETEnabled);
+    }
+
+    if (    (m->sv >= SettingsVersion_v1_11)
+       )
+    {
+        if (hw.chipsetType != ChipsetType_PIIX3)
+        {
+            xml::ElementNode *pelmChipset = pelmHardware->createChild("Chipset");
+            const char *pcszChipset;
+
+            switch (hw.chipsetType)
+            {
+                case ChipsetType_PIIX3:             pcszChipset = "PIIX3";   break;
+                case ChipsetType_ICH9:              pcszChipset = "ICH9";    break;
+                default:            Assert(false);  pcszChipset = "PIIX3";   break;
+            }
+            pelmChipset->setAttribute("type", pcszChipset);
+        }
+    }
+
+    if (    (m->sv >= SettingsVersion_v1_15)
+        && !hw.areParavirtDefaultSettings(m->sv)
+       )
+    {
+        const char *pcszParavirtProvider;
+        switch (hw.paravirtProvider)
+        {
+            case ParavirtProvider_None:         pcszParavirtProvider = "None";     break;
+            case ParavirtProvider_Default:      pcszParavirtProvider = "Default";  break;
+            case ParavirtProvider_Legacy:       pcszParavirtProvider = "Legacy";   break;
+            case ParavirtProvider_Minimal:      pcszParavirtProvider = "Minimal";  break;
+            case ParavirtProvider_HyperV:       pcszParavirtProvider = "HyperV";   break;
+            case ParavirtProvider_KVM:          pcszParavirtProvider = "KVM";      break;
+            default:            Assert(false);  pcszParavirtProvider = "None";     break;
+        }
+
+        xml::ElementNode *pelmParavirt = pelmHardware->createChild("Paravirt");
+        pelmParavirt->setAttribute("provider", pcszParavirtProvider);
+
+        if (   m->sv >= SettingsVersion_v1_16
+            && hw.strParavirtDebug.isNotEmpty())
+            pelmParavirt->setAttribute("debug", hw.strParavirtDebug);
+    }
+
+    if (   m->sv >= SettingsVersion_v1_19
+        && hw.iommuType != IommuType_None)
+    {
+        const char *pcszIommuType;
+        switch (hw.iommuType)
+        {
+            case IommuType_None:         pcszIommuType = "None";        break;
+            case IommuType_Automatic:    pcszIommuType = "Automatic";   break;
+            case IommuType_AMD:          pcszIommuType = "AMD";         break;
+            case IommuType_Intel:        pcszIommuType = "Intel";       break;
+            default:     Assert(false);  pcszIommuType = "None";        break;
+        }
+
+        xml::ElementNode *pelmIommu = pelmHardware->createChild("Iommu");
+        pelmIommu->setAttribute("type", pcszIommuType);
+    }
+
+    if (!hw.areBootOrderDefaultSettings())
+    {
+        xml::ElementNode *pelmBoot = pelmHardware->createChild("Boot");
+        for (BootOrderMap::const_iterator it = hw.mapBootOrder.begin();
+             it != hw.mapBootOrder.end();
+             ++it)
+        {
+            uint32_t i = it->first;
+            DeviceType_T type = it->second;
+            const char *pcszDevice;
+
+            switch (type)
+            {
+                case DeviceType_Floppy:     pcszDevice = "Floppy"; break;
+                case DeviceType_DVD:        pcszDevice = "DVD"; break;
+                case DeviceType_HardDisk:   pcszDevice = "HardDisk"; break;
+                case DeviceType_Network:    pcszDevice = "Network"; break;
+                default: /*case DeviceType_Null:*/      pcszDevice = "None"; break;
+            }
+
+            xml::ElementNode *pelmOrder = pelmBoot->createChild("Order");
+            pelmOrder->setAttribute("position",
+                                    i + 1);   // XML is 1-based but internal data is 0-based
+            pelmOrder->setAttribute("device", pcszDevice);
+        }
+    }
+
+    if (!hw.graphicsAdapter.areDefaultSettings())
+    {
+        xml::ElementNode *pelmDisplay = pelmHardware->createChild("Display");
+        if (hw.graphicsAdapter.graphicsControllerType != GraphicsControllerType_VBoxVGA)
+        {
+            const char *pcszGraphics;
+            switch (hw.graphicsAdapter.graphicsControllerType)
+            {
+                case GraphicsControllerType_VBoxVGA:            pcszGraphics = "VBoxVGA"; break;
+                case GraphicsControllerType_VMSVGA:             pcszGraphics = "VMSVGA"; break;
+                case GraphicsControllerType_VBoxSVGA:           pcszGraphics = "VBoxSVGA"; break;
+                default: /*case GraphicsControllerType_Null:*/  pcszGraphics = "None"; break;
+            }
+            pelmDisplay->setAttribute("controller", pcszGraphics);
+        }
+        if (hw.graphicsAdapter.ulVRAMSizeMB != 8)
+            pelmDisplay->setAttribute("VRAMSize", hw.graphicsAdapter.ulVRAMSizeMB);
+        if (hw.graphicsAdapter.cMonitors > 1)
+            pelmDisplay->setAttribute("monitorCount", hw.graphicsAdapter.cMonitors);
+        if (hw.graphicsAdapter.fAccelerate3D)
+            pelmDisplay->setAttribute("accelerate3D", hw.graphicsAdapter.fAccelerate3D);
+
+        if (m->sv >= SettingsVersion_v1_8)
+        {
+            if (hw.graphicsAdapter.fAccelerate2DVideo)
+                pelmDisplay->setAttribute("accelerate2DVideo", hw.graphicsAdapter.fAccelerate2DVideo);
+        }
+    }
+
+    if (!hw.vrdeSettings.areDefaultSettings(m->sv))
+    {
+        xml::ElementNode *pelmVRDE = pelmHardware->createChild("RemoteDisplay");
+        if (m->sv < SettingsVersion_v1_16 ? !hw.vrdeSettings.fEnabled : hw.vrdeSettings.fEnabled)
+            pelmVRDE->setAttribute("enabled", hw.vrdeSettings.fEnabled);
+        if (m->sv < SettingsVersion_v1_11)
+        {
+            /* In VBox 4.0 these attributes are replaced with "Properties". */
+            Utf8Str strPort;
+            StringsMap::const_iterator it = hw.vrdeSettings.mapProperties.find("TCP/Ports");
+            if (it != hw.vrdeSettings.mapProperties.end())
+                strPort = it->second;
+            if (!strPort.length())
+                strPort = "3389";
+            pelmVRDE->setAttribute("port", strPort);
+
+            Utf8Str strAddress;
+            it = hw.vrdeSettings.mapProperties.find("TCP/Address");
+            if (it != hw.vrdeSettings.mapProperties.end())
+                strAddress = it->second;
+            if (strAddress.length())
+                pelmVRDE->setAttribute("netAddress", strAddress);
+        }
+        if (hw.vrdeSettings.authType != AuthType_Null)
+        {
+            const char *pcszAuthType;
+            switch (hw.vrdeSettings.authType)
+            {
+                case AuthType_Guest:    pcszAuthType = "Guest";    break;
+                case AuthType_External: pcszAuthType = "External"; break;
+                default: /*case AuthType_Null:*/ pcszAuthType = "Null"; break;
+            }
+            pelmVRDE->setAttribute("authType", pcszAuthType);
+        }
+
+        if (hw.vrdeSettings.ulAuthTimeout != 0 && hw.vrdeSettings.ulAuthTimeout != 5000)
+            pelmVRDE->setAttribute("authTimeout", hw.vrdeSettings.ulAuthTimeout);
+        if (hw.vrdeSettings.fAllowMultiConnection)
+            pelmVRDE->setAttribute("allowMultiConnection", hw.vrdeSettings.fAllowMultiConnection);
+        if (hw.vrdeSettings.fReuseSingleConnection)
+            pelmVRDE->setAttribute("reuseSingleConnection", hw.vrdeSettings.fReuseSingleConnection);
+
+        if (m->sv == SettingsVersion_v1_10)
+        {
+            xml::ElementNode *pelmVideoChannel = pelmVRDE->createChild("VideoChannel");
+
+            /* In 4.0 videochannel settings were replaced with properties, so look at properties. */
+            Utf8Str str;
+            StringsMap::const_iterator it = hw.vrdeSettings.mapProperties.find("VideoChannel/Enabled");
+            if (it != hw.vrdeSettings.mapProperties.end())
+                str = it->second;
+            bool fVideoChannel =    RTStrICmp(str.c_str(), "true") == 0
+                                 || RTStrCmp(str.c_str(), "1") == 0;
+            pelmVideoChannel->setAttribute("enabled", fVideoChannel);
+
+            it = hw.vrdeSettings.mapProperties.find("VideoChannel/Quality");
+            if (it != hw.vrdeSettings.mapProperties.end())
+                str = it->second;
+            uint32_t ulVideoChannelQuality = RTStrToUInt32(str.c_str()); /* This returns 0 on invalid string which is ok. */
+            if (ulVideoChannelQuality == 0)
+                ulVideoChannelQuality = 75;
+            else
+                ulVideoChannelQuality = RT_CLAMP(ulVideoChannelQuality, 10, 100);
+            pelmVideoChannel->setAttribute("quality", ulVideoChannelQuality);
+        }
+        if (m->sv >= SettingsVersion_v1_11)
+        {
+            if (hw.vrdeSettings.strAuthLibrary.length())
+                pelmVRDE->setAttribute("authLibrary", hw.vrdeSettings.strAuthLibrary);
+            if (hw.vrdeSettings.strVrdeExtPack.isNotEmpty())
+                pelmVRDE->setAttribute("VRDEExtPack", hw.vrdeSettings.strVrdeExtPack);
+            if (hw.vrdeSettings.mapProperties.size() > 0)
+            {
+                xml::ElementNode *pelmProperties = pelmVRDE->createChild("VRDEProperties");
+                for (StringsMap::const_iterator it = hw.vrdeSettings.mapProperties.begin();
+                     it != hw.vrdeSettings.mapProperties.end();
+                     ++it)
+                {
+                    const Utf8Str &strName = it->first;
+                    const Utf8Str &strValue = it->second;
+                    xml::ElementNode *pelm = pelmProperties->createChild("Property");
+                    pelm->setAttribute("name", strName);
+                    pelm->setAttribute("value", strValue);
+                }
+            }
+        }
+    }
+
+    if (!hw.biosSettings.areDefaultSettings() || !hw.nvramSettings.areDefaultSettings())
+    {
+        xml::ElementNode *pelmBIOS = pelmHardware->createChild("BIOS");
+        if (!hw.biosSettings.fACPIEnabled)
+            pelmBIOS->createChild("ACPI")->setAttribute("enabled", hw.biosSettings.fACPIEnabled);
+        if (hw.biosSettings.fIOAPICEnabled)
+            pelmBIOS->createChild("IOAPIC")->setAttribute("enabled", hw.biosSettings.fIOAPICEnabled);
+        if (hw.biosSettings.apicMode != APICMode_APIC)
+        {
+            const char *pcszAPIC;
+            switch (hw.biosSettings.apicMode)
+            {
+                case APICMode_Disabled:
+                    pcszAPIC = "Disabled";
+                    break;
+                case APICMode_APIC:
+                default:
+                    pcszAPIC = "APIC";
+                    break;
+                case APICMode_X2APIC:
+                    pcszAPIC = "X2APIC";
+                    break;
+            }
+            pelmBIOS->createChild("APIC")->setAttribute("mode", pcszAPIC);
+        }
+
+        if (   !hw.biosSettings.fLogoFadeIn
+            || !hw.biosSettings.fLogoFadeOut
+            || hw.biosSettings.ulLogoDisplayTime
+            || !hw.biosSettings.strLogoImagePath.isEmpty())
+        {
+            xml::ElementNode *pelmLogo = pelmBIOS->createChild("Logo");
+            pelmLogo->setAttribute("fadeIn", hw.biosSettings.fLogoFadeIn);
+            pelmLogo->setAttribute("fadeOut", hw.biosSettings.fLogoFadeOut);
+            pelmLogo->setAttribute("displayTime", hw.biosSettings.ulLogoDisplayTime);
+            if (!hw.biosSettings.strLogoImagePath.isEmpty())
+                pelmLogo->setAttribute("imagePath", hw.biosSettings.strLogoImagePath);
+        }
+
+        if (hw.biosSettings.biosBootMenuMode != BIOSBootMenuMode_MessageAndMenu)
+        {
+            const char *pcszBootMenu;
+            switch (hw.biosSettings.biosBootMenuMode)
+            {
+                case BIOSBootMenuMode_Disabled: pcszBootMenu = "Disabled"; break;
+                case BIOSBootMenuMode_MenuOnly: pcszBootMenu = "MenuOnly"; break;
+                default: /*BIOSBootMenuMode_MessageAndMenu*/ pcszBootMenu = "MessageAndMenu"; break;
+            }
+            pelmBIOS->createChild("BootMenu")->setAttribute("mode", pcszBootMenu);
+        }
+        if (hw.biosSettings.llTimeOffset)
+            pelmBIOS->createChild("TimeOffset")->setAttribute("value", hw.biosSettings.llTimeOffset);
+        if (hw.biosSettings.fPXEDebugEnabled)
+            pelmBIOS->createChild("PXEDebug")->setAttribute("enabled", hw.biosSettings.fPXEDebugEnabled);
+        if (!hw.nvramSettings.areDefaultSettings())
+        {
+            xml::ElementNode *pelmNvram = pelmBIOS->createChild("NVRAM");
+            if (!hw.nvramSettings.strNvramPath.isEmpty())
+                pelmNvram->setAttribute("path", hw.nvramSettings.strNvramPath);
+            if (m->sv >= SettingsVersion_v1_9)
+            {
+                if (hw.nvramSettings.strKeyId.isNotEmpty())
+                    pelmNvram->setAttribute("keyId", hw.nvramSettings.strKeyId);
+                if (hw.nvramSettings.strKeyStore.isNotEmpty())
+                    pelmNvram->setAttribute("keyStore", hw.nvramSettings.strKeyStore);
+            }
+        }
+        if (hw.biosSettings.fSmbiosUuidLittleEndian)
+            pelmBIOS->createChild("SmbiosUuidLittleEndian")->setAttribute("enabled", hw.biosSettings.fSmbiosUuidLittleEndian);
+    }
+
+    if (!hw.tpmSettings.areDefaultSettings())
+    {
+        xml::ElementNode *pelmTpm = pelmHardware->createChild("TrustedPlatformModule");
+
+        const char *pcszTpm;
+        switch (hw.tpmSettings.tpmType)
+        {
+            default:
+            case TpmType_None:
+                pcszTpm = "None";
+                break;
+            case TpmType_v1_2:
+                pcszTpm = "v1_2";
+                break;
+            case TpmType_v2_0:
+                pcszTpm = "v2_0";
+                break;
+            case TpmType_Host:
+                pcszTpm = "Host";
+                break;
+            case TpmType_Swtpm:
+                pcszTpm = "Swtpm";
+                break;
+        }
+        pelmTpm->setAttribute("type", pcszTpm);
+        pelmTpm->setAttribute("location", hw.tpmSettings.strLocation);
+    }
+
+    if (m->sv < SettingsVersion_v1_9)
+    {
+        // settings formats before 1.9 had separate DVDDrive and FloppyDrive items under Hardware;
+        // run thru the storage controllers to see if we have a DVD or floppy drives
+        size_t cDVDs = 0;
+        size_t cFloppies = 0;
+
+        xml::ElementNode *pelmDVD = pelmHardware->createChild("DVDDrive");
+        xml::ElementNode *pelmFloppy = pelmHardware->createChild("FloppyDrive");
+
+        for (StorageControllersList::const_iterator it = hw.storage.llStorageControllers.begin();
+             it != hw.storage.llStorageControllers.end();
+             ++it)
+        {
+            const StorageController &sctl = *it;
+            // in old settings format, the DVD drive could only have been under the IDE controller
+            if (sctl.storageBus == StorageBus_IDE)
+            {
+                for (AttachedDevicesList::const_iterator it2 = sctl.llAttachedDevices.begin();
+                     it2 != sctl.llAttachedDevices.end();
+                     ++it2)
+                {
+                    const AttachedDevice &att = *it2;
+                    if (att.deviceType == DeviceType_DVD)
+                    {
+                        if (cDVDs > 0)
+                            throw ConfigFileError(this, NULL, N_("Internal error: cannot save more than one DVD drive with old settings format"));
+
+                        ++cDVDs;
+
+                        pelmDVD->setAttribute("passthrough", att.fPassThrough);
+                        if (att.fTempEject)
+                            pelmDVD->setAttribute("tempeject", att.fTempEject);
+
+                        if (!att.uuid.isZero() && att.uuid.isValid())
+                            pelmDVD->createChild("Image")->setAttribute("uuid", att.uuid.toStringCurly());
+                        else if (att.strHostDriveSrc.length())
+                            pelmDVD->createChild("HostDrive")->setAttribute("src", att.strHostDriveSrc);
+                    }
+                }
+            }
+            else if (sctl.storageBus == StorageBus_Floppy)
+            {
+                size_t cFloppiesHere = sctl.llAttachedDevices.size();
+                if (cFloppiesHere > 1)
+                    throw ConfigFileError(this, NULL, N_("Internal error: floppy controller cannot have more than one device attachment"));
+                if (cFloppiesHere)
+                {
+                    const AttachedDevice &att = sctl.llAttachedDevices.front();
+                    pelmFloppy->setAttribute("enabled", true);
+
+                    if (!att.uuid.isZero() && att.uuid.isValid())
+                        pelmFloppy->createChild("Image")->setAttribute("uuid", att.uuid.toStringCurly());
+                    else if (att.strHostDriveSrc.length())
+                        pelmFloppy->createChild("HostDrive")->setAttribute("src", att.strHostDriveSrc);
+                }
+
+                cFloppies += cFloppiesHere;
+            }
+        }
+
+        if (cFloppies == 0)
+            pelmFloppy->setAttribute("enabled", false);
+        else if (cFloppies > 1)
+            throw ConfigFileError(this, NULL, N_("Internal error: cannot save more than one floppy drive with old settings format"));
+    }
+
+    if (m->sv < SettingsVersion_v1_14)
+    {
+        bool fOhciEnabled = false;
+        bool fEhciEnabled = false;
+        xml::ElementNode *pelmUSB = pelmHardware->createChild("USBController");
+
+        for (USBControllerList::const_iterator it = hw.usbSettings.llUSBControllers.begin();
+             it != hw.usbSettings.llUSBControllers.end();
+             ++it)
+        {
+            const USBController &ctrl = *it;
+
+            switch (ctrl.enmType)
+            {
+                case USBControllerType_OHCI:
+                    fOhciEnabled = true;
+                    break;
+                case USBControllerType_EHCI:
+                    fEhciEnabled = true;
+                    break;
+                default:
+                    AssertMsgFailed(("Unknown USB controller type %d\n", ctrl.enmType));
+            }
+        }
+
+        pelmUSB->setAttribute("enabled", fOhciEnabled);
+        pelmUSB->setAttribute("enabledEhci", fEhciEnabled);
+
+        buildUSBDeviceFilters(*pelmUSB, hw.usbSettings.llDeviceFilters, false /* fHostMode */);
+    }
+    else
+    {
+        if (   hw.usbSettings.llUSBControllers.size()
+            || hw.usbSettings.llDeviceFilters.size())
+        {
+            xml::ElementNode *pelmUSB = pelmHardware->createChild("USB");
+            if (hw.usbSettings.llUSBControllers.size())
+            {
+                xml::ElementNode *pelmCtrls = pelmUSB->createChild("Controllers");
+
+                for (USBControllerList::const_iterator it = hw.usbSettings.llUSBControllers.begin();
+                     it != hw.usbSettings.llUSBControllers.end();
+                     ++it)
+                {
+                    const USBController &ctrl = *it;
+                    com::Utf8Str strType;
+                    xml::ElementNode *pelmCtrl = pelmCtrls->createChild("Controller");
+
+                    switch (ctrl.enmType)
+                    {
+                        case USBControllerType_OHCI:
+                            strType = "OHCI";
+                            break;
+                        case USBControllerType_EHCI:
+                            strType = "EHCI";
+                            break;
+                        case USBControllerType_XHCI:
+                            strType = "XHCI";
+                            break;
+                        default:
+                            AssertMsgFailed(("Unknown USB controller type %d\n", ctrl.enmType));
+                    }
+
+                    pelmCtrl->setAttribute("name", ctrl.strName);
+                    pelmCtrl->setAttribute("type", strType);
+                }
+            }
+
+            if (hw.usbSettings.llDeviceFilters.size())
+            {
+                xml::ElementNode *pelmFilters = pelmUSB->createChild("DeviceFilters");
+                buildUSBDeviceFilters(*pelmFilters, hw.usbSettings.llDeviceFilters, false /* fHostMode */);
+            }
+        }
+    }
+
+    if (   hw.llNetworkAdapters.size()
+        && !hw.areAllNetworkAdaptersDefaultSettings(m->sv))
+    {
+        xml::ElementNode *pelmNetwork = pelmHardware->createChild("Network");
+        for (NetworkAdaptersList::const_iterator it = hw.llNetworkAdapters.begin();
+             it != hw.llNetworkAdapters.end();
+             ++it)
+        {
+            const NetworkAdapter &nic = *it;
+
+            if (!nic.areDefaultSettings(m->sv))
+            {
+                xml::ElementNode *pelmAdapter = pelmNetwork->createChild("Adapter");
+                pelmAdapter->setAttribute("slot", nic.ulSlot);
+                if (nic.fEnabled)
+                    pelmAdapter->setAttribute("enabled", nic.fEnabled);
+                if (!nic.strMACAddress.isEmpty())
+                    pelmAdapter->setAttribute("MACAddress", nic.strMACAddress);
+                if (   (m->sv >= SettingsVersion_v1_16 && !nic.fCableConnected)
+                    || (m->sv < SettingsVersion_v1_16 && nic.fCableConnected))
+                    pelmAdapter->setAttribute("cable", nic.fCableConnected);
+                if (nic.ulLineSpeed)
+                    pelmAdapter->setAttribute("speed", nic.ulLineSpeed);
+                if (nic.ulBootPriority != 0)
+                    pelmAdapter->setAttribute("bootPriority", nic.ulBootPriority);
+                if (nic.fTraceEnabled)
+                {
+                    pelmAdapter->setAttribute("trace", nic.fTraceEnabled);
+                    pelmAdapter->setAttribute("tracefile", nic.strTraceFile);
+                }
+                if (nic.strBandwidthGroup.isNotEmpty())
+                    pelmAdapter->setAttribute("bandwidthGroup", nic.strBandwidthGroup);
+
+                const char *pszPolicy;
+                switch (nic.enmPromiscModePolicy)
+                {
+                    case NetworkAdapterPromiscModePolicy_Deny:          pszPolicy = NULL; break;
+                    case NetworkAdapterPromiscModePolicy_AllowNetwork:  pszPolicy = "AllowNetwork"; break;
+                    case NetworkAdapterPromiscModePolicy_AllowAll:      pszPolicy = "AllowAll"; break;
+                    default:                                            pszPolicy = NULL; AssertFailed(); break;
+                }
+                if (pszPolicy)
+                    pelmAdapter->setAttribute("promiscuousModePolicy", pszPolicy);
+
+                if (   (m->sv >= SettingsVersion_v1_16 && nic.type != NetworkAdapterType_Am79C973)
+                    || (m->sv < SettingsVersion_v1_16 && nic.type != NetworkAdapterType_Am79C970A))
+                {
+                    const char *pcszType;
+                    switch (nic.type)
+                    {
+                        case NetworkAdapterType_Am79C973:   pcszType = "Am79C973"; break;
+                        case NetworkAdapterType_Am79C960:   pcszType = "Am79C960"; break;
+                        case NetworkAdapterType_I82540EM:   pcszType = "82540EM"; break;
+                        case NetworkAdapterType_I82543GC:   pcszType = "82543GC"; break;
+                        case NetworkAdapterType_I82545EM:   pcszType = "82545EM"; break;
+                        case NetworkAdapterType_Virtio:     pcszType = "virtio"; break;
+                        case NetworkAdapterType_NE1000:     pcszType = "NE1000"; break;
+                        case NetworkAdapterType_NE2000:     pcszType = "NE2000"; break;
+                        case NetworkAdapterType_WD8003:     pcszType = "WD8003"; break;
+                        case NetworkAdapterType_WD8013:     pcszType = "WD8013"; break;
+                        case NetworkAdapterType_ELNK2:      pcszType = "3C503"; break;
+                        case NetworkAdapterType_ELNK1:      pcszType = "3C501"; break;
+                        default: /*case NetworkAdapterType_Am79C970A:*/  pcszType = "Am79C970A"; break;
+                    }
+                    pelmAdapter->setAttribute("type", pcszType);
+                }
+
+                xml::ElementNode *pelmNAT;
+                if (m->sv < SettingsVersion_v1_10)
+                {
+                    switch (nic.mode)
+                    {
+                        case NetworkAttachmentType_NAT:
+                            pelmNAT = pelmAdapter->createChild("NAT");
+                            if (nic.nat.strNetwork.length())
+                                pelmNAT->setAttribute("network", nic.nat.strNetwork);
+                            break;
+
+                        case NetworkAttachmentType_Bridged:
+                            pelmAdapter->createChild("BridgedInterface")->setAttribute("name", nic.strBridgedName);
+                            break;
+
+                        case NetworkAttachmentType_Internal:
+                            pelmAdapter->createChild("InternalNetwork")->setAttribute("name", nic.strInternalNetworkName);
+                            break;
+
+                        case NetworkAttachmentType_HostOnly:
+                            pelmAdapter->createChild("HostOnlyInterface")->setAttribute("name", nic.strHostOnlyName);
+                            break;
+
+                        default: /*case NetworkAttachmentType_Null:*/
+                            break;
+                    }
+                }
+                else
+                {
+                    /* m->sv >= SettingsVersion_v1_10 */
+                    if (!nic.areDisabledDefaultSettings(m->sv))
+                    {
+                        xml::ElementNode *pelmDisabledNode = pelmAdapter->createChild("DisabledModes");
+                        if (nic.mode != NetworkAttachmentType_NAT)
+                            buildNetworkXML(NetworkAttachmentType_NAT, false, *pelmDisabledNode, nic);
+                        if (nic.mode != NetworkAttachmentType_Bridged)
+                            buildNetworkXML(NetworkAttachmentType_Bridged, false, *pelmDisabledNode, nic);
+                        if (nic.mode != NetworkAttachmentType_Internal)
+                            buildNetworkXML(NetworkAttachmentType_Internal, false, *pelmDisabledNode, nic);
+                        if (nic.mode != NetworkAttachmentType_HostOnly)
+                            buildNetworkXML(NetworkAttachmentType_HostOnly, false, *pelmDisabledNode, nic);
+                        if (nic.mode != NetworkAttachmentType_Generic)
+                            buildNetworkXML(NetworkAttachmentType_Generic, false, *pelmDisabledNode, nic);
+                        if (nic.mode != NetworkAttachmentType_NATNetwork)
+                            buildNetworkXML(NetworkAttachmentType_NATNetwork, false, *pelmDisabledNode, nic);
+#ifdef VBOX_WITH_CLOUD_NET
+                        /// @todo Bump settings version!
+                        if (nic.mode != NetworkAttachmentType_Cloud)
+                            buildNetworkXML(NetworkAttachmentType_Cloud, false, *pelmDisabledNode, nic);
+#endif /* VBOX_WITH_CLOUD_NET */
+#ifdef VBOX_WITH_VMNET
+                        if (nic.mode != NetworkAttachmentType_HostOnlyNetwork)
+                            buildNetworkXML(NetworkAttachmentType_HostOnlyNetwork, false, *pelmDisabledNode, nic);
+#endif /* VBOX_WITH_VMNET */
+                    }
+                    buildNetworkXML(nic.mode, true, *pelmAdapter, nic);
+                }
+            }
+        }
+    }
+
+    if (hw.llSerialPorts.size())
+    {
+        xml::ElementNode *pelmPorts = pelmHardware->createChild("UART");
+        for (SerialPortsList::const_iterator it = hw.llSerialPorts.begin();
+             it != hw.llSerialPorts.end();
+             ++it)
+        {
+            const SerialPort &port = *it;
+            xml::ElementNode *pelmPort = pelmPorts->createChild("Port");
+            pelmPort->setAttribute("slot", port.ulSlot);
+            pelmPort->setAttribute("enabled", port.fEnabled);
+            pelmPort->setAttributeHex("IOBase", port.ulIOBase);
+            pelmPort->setAttribute("IRQ", port.ulIRQ);
+
+            const char *pcszHostMode;
+            switch (port.portMode)
+            {
+                case PortMode_HostPipe: pcszHostMode = "HostPipe"; break;
+                case PortMode_HostDevice: pcszHostMode = "HostDevice"; break;
+                case PortMode_TCP: pcszHostMode = "TCP"; break;
+                case PortMode_RawFile: pcszHostMode = "RawFile"; break;
+                default: /*case PortMode_Disconnected:*/ pcszHostMode = "Disconnected"; break;
+            }
+            switch (port.portMode)
+            {
+                case PortMode_TCP:
+                case PortMode_HostPipe:
+                    pelmPort->setAttribute("server", port.fServer);
+                    RT_FALL_THRU();
+                case PortMode_HostDevice:
+                case PortMode_RawFile:
+                    pelmPort->setAttribute("path", port.strPath);
+                    break;
+
+                default:
+                    break;
+            }
+            pelmPort->setAttribute("hostMode", pcszHostMode);
+
+            if (   m->sv >= SettingsVersion_v1_17
+                && port.uartType != UartType_U16550A)
+            {
+                const char *pcszUartType;
+
+                switch (port.uartType)
+                {
+                    case UartType_U16450: pcszUartType = "16450"; break;
+                    case UartType_U16550A: pcszUartType = "16550A"; break;
+                    case UartType_U16750: pcszUartType = "16750"; break;
+                    default: pcszUartType = "16550A"; break;
+                }
+                pelmPort->setAttribute("uartType", pcszUartType);
+            }
+        }
+    }
+
+    if (hw.llParallelPorts.size())
+    {
+        xml::ElementNode *pelmPorts = pelmHardware->createChild("LPT");
+        for (ParallelPortsList::const_iterator it = hw.llParallelPorts.begin();
+             it != hw.llParallelPorts.end();
+             ++it)
+        {
+            const ParallelPort &port = *it;
+            xml::ElementNode *pelmPort = pelmPorts->createChild("Port");
+            pelmPort->setAttribute("slot", port.ulSlot);
+            pelmPort->setAttribute("enabled", port.fEnabled);
+            pelmPort->setAttributeHex("IOBase", port.ulIOBase);
+            pelmPort->setAttribute("IRQ", port.ulIRQ);
+            if (port.strPath.length())
+                pelmPort->setAttribute("path", port.strPath);
+        }
+    }
+
+    /* Always write the AudioAdapter config, intentionally not checking if
+     * the settings are at the default, because that would be problematic
+     * for the configured host driver type, which would automatically change
+     * if the default host driver is detected differently. */
+    {
+        xml::ElementNode *pelmAudio = pelmHardware->createChild("AudioAdapter");
+
+        const char *pcszController;
+        switch (hw.audioAdapter.controllerType)
+        {
+            case AudioControllerType_SB16:
+                pcszController = "SB16";
+                break;
+            case AudioControllerType_HDA:
+                if (m->sv >= SettingsVersion_v1_11)
+                {
+                    pcszController = "HDA";
+                    break;
+                }
+                RT_FALL_THRU();
+            case AudioControllerType_AC97:
+            default:
+                pcszController = NULL;
+                break;
+        }
+        if (pcszController)
+            pelmAudio->setAttribute("controller", pcszController);
+
+        const char *pcszCodec;
+        switch (hw.audioAdapter.codecType)
+        {
+            /* Only write out the setting for non-default AC'97 codec
+             * and leave the rest alone.
+             */
+#if 0
+            case AudioCodecType_SB16:
+                pcszCodec = "SB16";
+                break;
+            case AudioCodecType_STAC9221:
+                pcszCodec = "STAC9221";
+                break;
+            case AudioCodecType_STAC9700:
+                pcszCodec = "STAC9700";
+                break;
+#endif
+            case AudioCodecType_AD1980:
+                pcszCodec = "AD1980";
+                break;
+            default:
+                /* Don't write out anything if unknown. */
+                pcszCodec = NULL;
+        }
+        if (pcszCodec)
+            pelmAudio->setAttribute("codec", pcszCodec);
+
+        /*
+         * Keep settings >= 1.19 compatible with older VBox versions (on a best effort basis, of course).
+         * So use a dedicated attribute for the new "Default" audio driver type, which did not exist prior
+         * settings 1.19 (VBox 7.0) and explicitly set the driver type to something older VBox versions
+         * know about.
+         */
+        AudioDriverType_T driverType = hw.audioAdapter.driverType;
+
+        if (driverType == AudioDriverType_Default)
+        {
+            /* Only recognized by VBox >= 7.0. */
+            pelmAudio->setAttribute("useDefault", true);
+
+            /* Make sure to set the actual driver type to the OS' default driver type.
+             * This is required for VBox < 7.0. */
+            driverType = getHostDefaultAudioDriver();
+        }
+
+        const char *pcszDriver = NULL;
+        switch (driverType)
+        {
+            case AudioDriverType_Default: /* Handled above. */                  break;
+            case AudioDriverType_WinMM:             pcszDriver = "WinMM";       break;
+            case AudioDriverType_DirectSound:       pcszDriver = "DirectSound"; break;
+            case AudioDriverType_WAS:               pcszDriver = "WAS";         break;
+            case AudioDriverType_ALSA:              pcszDriver = "ALSA";        break;
+            case AudioDriverType_OSS:               pcszDriver = "OSS";         break;
+            case AudioDriverType_Pulse:             pcszDriver = "Pulse";       break;
+            case AudioDriverType_CoreAudio:         pcszDriver = "CoreAudio";   break;
+            case AudioDriverType_SolAudio:          pcszDriver = "SolAudio";    break;
+            case AudioDriverType_MMPM:              pcszDriver = "MMPM";        break;
+            default: /*case AudioDriverType_Null:*/ pcszDriver = "Null";        break;
+        }
+
+        /* Deliberately have the audio driver explicitly in the config file,
+         * otherwise an unwritten default driver triggers auto-detection. */
+        AssertStmt(pcszDriver != NULL, pcszDriver = "Null");
+        pelmAudio->setAttribute("driver", pcszDriver);
+
+        if (hw.audioAdapter.fEnabled || m->sv < SettingsVersion_v1_16)
+            pelmAudio->setAttribute("enabled", hw.audioAdapter.fEnabled);
+
+        if (   (m->sv <= SettingsVersion_v1_16 && !hw.audioAdapter.fEnabledIn)
+            || (m->sv > SettingsVersion_v1_16 && hw.audioAdapter.fEnabledIn))
+            pelmAudio->setAttribute("enabledIn", hw.audioAdapter.fEnabledIn);
+
+        if (   (m->sv <= SettingsVersion_v1_16 && !hw.audioAdapter.fEnabledOut)
+            || (m->sv > SettingsVersion_v1_16 && hw.audioAdapter.fEnabledOut))
+            pelmAudio->setAttribute("enabledOut", hw.audioAdapter.fEnabledOut);
+
+        if (m->sv >= SettingsVersion_v1_15 && hw.audioAdapter.properties.size() > 0)
+        {
+            for (StringsMap::const_iterator it = hw.audioAdapter.properties.begin();
+                 it != hw.audioAdapter.properties.end();
+                 ++it)
+            {
+                const Utf8Str &strName = it->first;
+                const Utf8Str &strValue = it->second;
+                xml::ElementNode *pelm = pelmAudio->createChild("Property");
+                pelm->setAttribute("name", strName);
+                pelm->setAttribute("value", strValue);
+            }
+        }
+    }
+
+    if (m->sv >= SettingsVersion_v1_10 && machineUserData.fRTCUseUTC)
+    {
+        xml::ElementNode *pelmRTC = pelmHardware->createChild("RTC");
+        pelmRTC->setAttribute("localOrUTC", machineUserData.fRTCUseUTC ? "UTC" : "local");
+    }
+
+    if (hw.llSharedFolders.size())
+    {
+        xml::ElementNode *pelmSharedFolders = pelmHardware->createChild("SharedFolders");
+        for (SharedFoldersList::const_iterator it = hw.llSharedFolders.begin();
+             it != hw.llSharedFolders.end();
+             ++it)
+        {
+            const SharedFolder &sf = *it;
+            xml::ElementNode *pelmThis = pelmSharedFolders->createChild("SharedFolder");
+            pelmThis->setAttribute("name", sf.strName);
+            pelmThis->setAttribute("hostPath", sf.strHostPath);
+            pelmThis->setAttribute("writable", sf.fWritable);
+            pelmThis->setAttribute("autoMount", sf.fAutoMount);
+            if (sf.strAutoMountPoint.isNotEmpty())
+                pelmThis->setAttribute("autoMountPoint", sf.strAutoMountPoint);
+        }
+    }
+
+    xml::ElementNode *pelmClip = pelmHardware->createChild("Clipboard");
+    if (pelmClip)
+    {
+        if (hw.clipboardMode != ClipboardMode_Disabled)
+        {
+            const char *pcszClip;
+            switch (hw.clipboardMode)
+            {
+                default: /*case ClipboardMode_Disabled:*/ pcszClip = "Disabled"; break;
+                case ClipboardMode_HostToGuest: pcszClip = "HostToGuest"; break;
+                case ClipboardMode_GuestToHost: pcszClip = "GuestToHost"; break;
+                case ClipboardMode_Bidirectional: pcszClip = "Bidirectional"; break;
+            }
+            pelmClip->setAttribute("mode", pcszClip);
+        }
+
+        if (hw.fClipboardFileTransfersEnabled)
+            pelmClip->setAttribute("fileTransfersEnabled", hw.fClipboardFileTransfersEnabled);
+    }
+
+    if (hw.dndMode != DnDMode_Disabled)
+    {
+        xml::ElementNode *pelmDragAndDrop = pelmHardware->createChild("DragAndDrop");
+        const char *pcszDragAndDrop;
+        switch (hw.dndMode)
+        {
+            default: /*case DnDMode_Disabled:*/ pcszDragAndDrop = "Disabled"; break;
+            case DnDMode_HostToGuest: pcszDragAndDrop = "HostToGuest"; break;
+            case DnDMode_GuestToHost: pcszDragAndDrop = "GuestToHost"; break;
+            case DnDMode_Bidirectional: pcszDragAndDrop = "Bidirectional"; break;
+        }
+        pelmDragAndDrop->setAttribute("mode", pcszDragAndDrop);
+    }
+
+    if (   m->sv >= SettingsVersion_v1_10
+        && !hw.ioSettings.areDefaultSettings())
+    {
+        xml::ElementNode *pelmIO = pelmHardware->createChild("IO");
+        xml::ElementNode *pelmIOCache;
+
+        if (!hw.ioSettings.areDefaultSettings())
+        {
+            pelmIOCache = pelmIO->createChild("IoCache");
+            if (!hw.ioSettings.fIOCacheEnabled)
+                pelmIOCache->setAttribute("enabled", hw.ioSettings.fIOCacheEnabled);
+            if (hw.ioSettings.ulIOCacheSize != 5)
+                pelmIOCache->setAttribute("size", hw.ioSettings.ulIOCacheSize);
+        }
+
+        if (   m->sv >= SettingsVersion_v1_11
+            && hw.ioSettings.llBandwidthGroups.size())
+        {
+            xml::ElementNode *pelmBandwidthGroups = pelmIO->createChild("BandwidthGroups");
+            for (BandwidthGroupList::const_iterator it = hw.ioSettings.llBandwidthGroups.begin();
+                 it != hw.ioSettings.llBandwidthGroups.end();
+                 ++it)
+            {
+                const BandwidthGroup &gr = *it;
+                const char *pcszType;
+                xml::ElementNode *pelmThis = pelmBandwidthGroups->createChild("BandwidthGroup");
+                pelmThis->setAttribute("name", gr.strName);
+                switch (gr.enmType)
+                {
+                    case BandwidthGroupType_Network: pcszType = "Network"; break;
+                    default: /* BandwidthGrouptype_Disk */ pcszType = "Disk"; break;
+                }
+                pelmThis->setAttribute("type", pcszType);
+                if (m->sv >= SettingsVersion_v1_13)
+                    pelmThis->setAttribute("maxBytesPerSec", gr.cMaxBytesPerSec);
+                else
+                    pelmThis->setAttribute("maxMbPerSec", gr.cMaxBytesPerSec / _1M);
+            }
+        }
+    }
+
+    if (   m->sv >= SettingsVersion_v1_12
+        && hw.pciAttachments.size())
+    {
+        xml::ElementNode *pelmPCI = pelmHardware->createChild("HostPci");
+        xml::ElementNode *pelmPCIDevices = pelmPCI->createChild("Devices");
+
+        for (HostPCIDeviceAttachmentList::const_iterator it = hw.pciAttachments.begin();
+             it != hw.pciAttachments.end();
+             ++it)
+        {
+            const HostPCIDeviceAttachment &hpda = *it;
+
+            xml::ElementNode *pelmThis = pelmPCIDevices->createChild("Device");
+
+            pelmThis->setAttribute("host",  hpda.uHostAddress);
+            pelmThis->setAttribute("guest", hpda.uGuestAddress);
+            pelmThis->setAttribute("name",  hpda.strDeviceName);
+        }
+    }
+
+    if (   m->sv >= SettingsVersion_v1_12
+        && hw.fEmulatedUSBCardReader)
+    {
+        xml::ElementNode *pelmEmulatedUSB = pelmHardware->createChild("EmulatedUSB");
+
+        xml::ElementNode *pelmCardReader = pelmEmulatedUSB->createChild("CardReader");
+        pelmCardReader->setAttribute("enabled", hw.fEmulatedUSBCardReader);
+    }
+
+    if (   m->sv >= SettingsVersion_v1_14
+        && !hw.strDefaultFrontend.isEmpty())
+    {
+        xml::ElementNode *pelmFrontend = pelmHardware->createChild("Frontend");
+        xml::ElementNode *pelmDefault = pelmFrontend->createChild("Default");
+        pelmDefault->setAttribute("type", hw.strDefaultFrontend);
+    }
+
+    if (hw.ulMemoryBalloonSize)
+    {
+        xml::ElementNode *pelmGuest = pelmHardware->createChild("Guest");
+        pelmGuest->setAttribute("memoryBalloonSize", hw.ulMemoryBalloonSize);
+    }
+
+    if (hw.llGuestProperties.size())
+    {
+        xml::ElementNode *pelmGuestProps = pelmHardware->createChild("GuestProperties");
+        for (GuestPropertiesList::const_iterator it = hw.llGuestProperties.begin();
+             it != hw.llGuestProperties.end();
+             ++it)
+        {
+            const GuestProperty &prop = *it;
+            xml::ElementNode *pelmProp = pelmGuestProps->createChild("GuestProperty");
+            pelmProp->setAttribute("name", prop.strName);
+            pelmProp->setAttribute("value", prop.strValue);
+            pelmProp->setAttribute("timestamp", prop.timestamp);
+            pelmProp->setAttribute("flags", prop.strFlags);
+        }
+    }
+
+    /* Starting with settings version of 6.0 (and only 6.1 and later does this, while
+     * 5.2 and 6.0 understand it), place storage controller settings under hardware,
+     * where it always should've been. */
+    xml::ElementNode &elmStorageParent = (m->sv >= SettingsVersion_v1_17) ? *pelmHardware : elmParent;
+    buildStorageControllersXML(elmStorageParent,
+                               hw.storage,
+                               !!(fl & BuildMachineXML_SkipRemovableMedia),
+                               pllElementsWithUuidAttributes);
+}
+
+/**
+ * Fill a \<Network\> node. Only relevant for XML version >= v1_10.
+ * @param mode
+ * @param fEnabled
+ * @param elmParent
+ * @param nic
+ */
+void MachineConfigFile::buildNetworkXML(NetworkAttachmentType_T mode,
+                                        bool fEnabled,
+                                        xml::ElementNode &elmParent,
+                                        const NetworkAdapter &nic)
+{
+    switch (mode)
+    {
+        case NetworkAttachmentType_NAT:
+            // For the currently active network attachment type we have to
+            // generate the tag, otherwise the attachment type is lost.
+            if (fEnabled || !nic.nat.areDefaultSettings(m->sv))
+            {
+                xml::ElementNode *pelmNAT = elmParent.createChild("NAT");
+
+                if (!nic.nat.areDefaultSettings(m->sv))
+                {
+                    if (nic.nat.strNetwork.length())
+                        pelmNAT->setAttribute("network", nic.nat.strNetwork);
+                    if (nic.nat.strBindIP.length())
+                        pelmNAT->setAttribute("hostip", nic.nat.strBindIP);
+                    if (nic.nat.u32Mtu)
+                        pelmNAT->setAttribute("mtu", nic.nat.u32Mtu);
+                    if (nic.nat.u32SockRcv)
+                        pelmNAT->setAttribute("sockrcv", nic.nat.u32SockRcv);
+                    if (nic.nat.u32SockSnd)
+                        pelmNAT->setAttribute("socksnd", nic.nat.u32SockSnd);
+                    if (nic.nat.u32TcpRcv)
+                        pelmNAT->setAttribute("tcprcv", nic.nat.u32TcpRcv);
+                    if (nic.nat.u32TcpSnd)
+                        pelmNAT->setAttribute("tcpsnd", nic.nat.u32TcpSnd);
+                    if (!nic.nat.areLocalhostReachableDefaultSettings(m->sv))
+                        pelmNAT->setAttribute("localhost-reachable", nic.nat.fLocalhostReachable);
+                    if (!nic.nat.areDNSDefaultSettings())
+                    {
+                        xml::ElementNode *pelmDNS = pelmNAT->createChild("DNS");
+                        if (!nic.nat.fDNSPassDomain)
+                            pelmDNS->setAttribute("pass-domain", nic.nat.fDNSPassDomain);
+                        if (nic.nat.fDNSProxy)
+                            pelmDNS->setAttribute("use-proxy", nic.nat.fDNSProxy);
+                        if (nic.nat.fDNSUseHostResolver)
+                            pelmDNS->setAttribute("use-host-resolver", nic.nat.fDNSUseHostResolver);
+                    }
+
+                    if (!nic.nat.areAliasDefaultSettings())
+                    {
+                        xml::ElementNode *pelmAlias = pelmNAT->createChild("Alias");
+                        if (nic.nat.fAliasLog)
+                            pelmAlias->setAttribute("logging", nic.nat.fAliasLog);
+                        if (nic.nat.fAliasProxyOnly)
+                            pelmAlias->setAttribute("proxy-only", nic.nat.fAliasProxyOnly);
+                        if (nic.nat.fAliasUseSamePorts)
+                            pelmAlias->setAttribute("use-same-ports", nic.nat.fAliasUseSamePorts);
+                    }
+
+                    if (!nic.nat.areTFTPDefaultSettings())
+                    {
+                        xml::ElementNode *pelmTFTP;
+                        pelmTFTP = pelmNAT->createChild("TFTP");
+                        if (nic.nat.strTFTPPrefix.length())
+                            pelmTFTP->setAttribute("prefix", nic.nat.strTFTPPrefix);
+                        if (nic.nat.strTFTPBootFile.length())
+                            pelmTFTP->setAttribute("boot-file", nic.nat.strTFTPBootFile);
+                        if (nic.nat.strTFTPNextServer.length())
+                            pelmTFTP->setAttribute("next-server", nic.nat.strTFTPNextServer);
+                    }
+                    buildNATForwardRulesMap(*pelmNAT, nic.nat.mapRules);
+                }
+            }
+            break;
+
+        case NetworkAttachmentType_Bridged:
+            // For the currently active network attachment type we have to
+            // generate the tag, otherwise the attachment type is lost.
+            if (fEnabled || !nic.strBridgedName.isEmpty())
+            {
+                xml::ElementNode *pelmMode = elmParent.createChild("BridgedInterface");
+                if (!nic.strBridgedName.isEmpty())
+                    pelmMode->setAttribute("name", nic.strBridgedName);
+            }
+            break;
+
+        case NetworkAttachmentType_Internal:
+            // For the currently active network attachment type we have to
+            // generate the tag, otherwise the attachment type is lost.
+            if (fEnabled || !nic.strInternalNetworkName.isEmpty())
+            {
+                xml::ElementNode *pelmMode = elmParent.createChild("InternalNetwork");
+                if (!nic.strInternalNetworkName.isEmpty())
+                    pelmMode->setAttribute("name", nic.strInternalNetworkName);
+            }
+            break;
+
+        case NetworkAttachmentType_HostOnly:
+            // For the currently active network attachment type we have to
+            // generate the tag, otherwise the attachment type is lost.
+            if (fEnabled || !nic.strHostOnlyName.isEmpty())
+            {
+                xml::ElementNode *pelmMode = elmParent.createChild("HostOnlyInterface");
+                if (!nic.strHostOnlyName.isEmpty())
+                    pelmMode->setAttribute("name", nic.strHostOnlyName);
+            }
+            break;
+
+#ifdef VBOX_WITH_VMNET
+        case NetworkAttachmentType_HostOnlyNetwork:
+            // For the currently active network attachment type we have to
+            // generate the tag, otherwise the attachment type is lost.
+            if (fEnabled || !nic.strHostOnlyNetworkName.isEmpty())
+            {
+                xml::ElementNode *pelmMode = elmParent.createChild("HostOnlyNetwork");
+                if (!nic.strHostOnlyNetworkName.isEmpty())
+                    pelmMode->setAttribute("name", nic.strHostOnlyNetworkName);
+            }
+            break;
+#endif /* VBOX_WITH_VMNET */
+
+        case NetworkAttachmentType_Generic:
+            // For the currently active network attachment type we have to
+            // generate the tag, otherwise the attachment type is lost.
+            if (fEnabled || !nic.areGenericDriverDefaultSettings())
+            {
+                xml::ElementNode *pelmMode = elmParent.createChild("GenericInterface");
+                if (!nic.areGenericDriverDefaultSettings())
+                {
+                    pelmMode->setAttribute("driver", nic.strGenericDriver);
+                    for (StringsMap::const_iterator it = nic.genericProperties.begin();
+                         it != nic.genericProperties.end();
+                         ++it)
+                    {
+                        xml::ElementNode *pelmProp = pelmMode->createChild("Property");
+                        pelmProp->setAttribute("name", it->first);
+                        pelmProp->setAttribute("value", it->second);
+                    }
+                }
+            }
+            break;
+
+        case NetworkAttachmentType_NATNetwork:
+            // For the currently active network attachment type we have to
+            // generate the tag, otherwise the attachment type is lost.
+            if (fEnabled || !nic.strNATNetworkName.isEmpty())
+            {
+                xml::ElementNode *pelmMode = elmParent.createChild("NATNetwork");
+                if (!nic.strNATNetworkName.isEmpty())
+                    pelmMode->setAttribute("name", nic.strNATNetworkName);
+            }
+            break;
+
+#ifdef VBOX_WITH_CLOUD_NET
+        case NetworkAttachmentType_Cloud:
+            // For the currently active network attachment type we have to
+            // generate the tag, otherwise the attachment type is lost.
+            if (fEnabled || !nic.strCloudNetworkName.isEmpty())
+            {
+                xml::ElementNode *pelmMode = elmParent.createChild("CloudNetwork");
+                if (!nic.strCloudNetworkName.isEmpty())
+                    pelmMode->setAttribute("name", nic.strCloudNetworkName);
+            }
+            break;
+#endif /* VBOX_WITH_CLOUD_NET */
+
+        default: /*case NetworkAttachmentType_Null:*/
+            break;
+    }
+}
+
+/**
+ * Creates a \<StorageControllers\> node under elmParent and then writes out the XML
+ * keys under that. Called for both the \<Machine\> node and for snapshots.
+ * @param elmParent
+ * @param st
+ * @param fSkipRemovableMedia If true, DVD and floppy attachments are skipped and
+ *   an empty drive is always written instead. This is for the OVF export case.
+ *   This parameter is ignored unless the settings version is at least v1.9, which
+ *   is always the case when this gets called for OVF export.
+ * @param pllElementsWithUuidAttributes If not NULL, must point to a list of element node
+ *   pointers to which we will append all elements that we created here that contain
+ *   UUID attributes. This allows the OVF export code to quickly replace the internal
+ *   media UUIDs with the UUIDs of the media that were exported.
+ */
+void MachineConfigFile::buildStorageControllersXML(xml::ElementNode &elmParent,
+                                                   const Storage &st,
+                                                   bool fSkipRemovableMedia,
+                                                   std::list<xml::ElementNode*> *pllElementsWithUuidAttributes)
+{
+    if (!st.llStorageControllers.size())
+        return;
+    xml::ElementNode *pelmStorageControllers = elmParent.createChild("StorageControllers");
+
+    for (StorageControllersList::const_iterator it = st.llStorageControllers.begin();
+         it != st.llStorageControllers.end();
+         ++it)
+    {
+        const StorageController &sc = *it;
+
+        if (    (m->sv < SettingsVersion_v1_9)
+             && (sc.controllerType == StorageControllerType_I82078)
+           )
+            // floppy controller already got written into <Hardware>/<FloppyController> in buildHardwareXML()
+            // for pre-1.9 settings
+            continue;
+
+        xml::ElementNode *pelmController = pelmStorageControllers->createChild("StorageController");
+        com::Utf8Str name = sc.strName;
+        if (m->sv < SettingsVersion_v1_8)
+        {
+            // pre-1.8 settings use shorter controller names, they are
+            // expanded when reading the settings
+            if (name == "IDE Controller")
+                name = "IDE";
+            else if (name == "SATA Controller")
+                name = "SATA";
+            else if (name == "SCSI Controller")
+                name = "SCSI";
+        }
+        pelmController->setAttribute("name", sc.strName);
+
+        const char *pcszType;
+        switch (sc.controllerType)
+        {
+            case StorageControllerType_IntelAhci: pcszType = "AHCI"; break;
+            case StorageControllerType_LsiLogic: pcszType = "LsiLogic"; break;
+            case StorageControllerType_BusLogic: pcszType = "BusLogic"; break;
+            case StorageControllerType_PIIX4: pcszType = "PIIX4"; break;
+            case StorageControllerType_ICH6: pcszType = "ICH6"; break;
+            case StorageControllerType_I82078: pcszType = "I82078"; break;
+            case StorageControllerType_LsiLogicSas: pcszType = "LsiLogicSas"; break;
+            case StorageControllerType_USB: pcszType = "USB"; break;
+            case StorageControllerType_NVMe: pcszType = "NVMe"; break;
+            case StorageControllerType_VirtioSCSI: pcszType = "VirtioSCSI"; break;
+            default: /*case StorageControllerType_PIIX3:*/ pcszType = "PIIX3"; break;
+        }
+        pelmController->setAttribute("type", pcszType);
+
+        pelmController->setAttribute("PortCount", sc.ulPortCount);
+
+        if (m->sv >= SettingsVersion_v1_9)
+            if (sc.ulInstance)
+                pelmController->setAttribute("Instance", sc.ulInstance);
+
+        if (m->sv >= SettingsVersion_v1_10)
+            pelmController->setAttribute("useHostIOCache", sc.fUseHostIOCache);
+
+        if (m->sv >= SettingsVersion_v1_11)
+            pelmController->setAttribute("Bootable", sc.fBootable);
+
+        if (sc.controllerType == StorageControllerType_IntelAhci)
+        {
+            pelmController->setAttribute("IDE0MasterEmulationPort", 0);
+            pelmController->setAttribute("IDE0SlaveEmulationPort", 1);
+            pelmController->setAttribute("IDE1MasterEmulationPort", 2);
+            pelmController->setAttribute("IDE1SlaveEmulationPort", 3);
+        }
+
+        for (AttachedDevicesList::const_iterator it2 = sc.llAttachedDevices.begin();
+             it2 != sc.llAttachedDevices.end();
+             ++it2)
+        {
+            const AttachedDevice &att = *it2;
+
+            // For settings version before 1.9, DVDs and floppies are in hardware, not storage controllers,
+            // so we shouldn't write them here; we only get here for DVDs though because we ruled out
+            // the floppy controller at the top of the loop
+            if (    att.deviceType == DeviceType_DVD
+                 && m->sv < SettingsVersion_v1_9
+               )
+                continue;
+
+            xml::ElementNode *pelmDevice = pelmController->createChild("AttachedDevice");
+
+            pcszType = NULL;
+
+            switch (att.deviceType)
+            {
+                case DeviceType_HardDisk:
+                    pcszType = "HardDisk";
+                    if (att.fNonRotational)
+                        pelmDevice->setAttribute("nonrotational", att.fNonRotational);
+                    if (att.fDiscard)
+                        pelmDevice->setAttribute("discard", att.fDiscard);
+                    break;
+
+                case DeviceType_DVD:
+                    pcszType = "DVD";
+                    pelmDevice->setAttribute("passthrough", att.fPassThrough);
+                    if (att.fTempEject)
+                        pelmDevice->setAttribute("tempeject", att.fTempEject);
+                    break;
+
+                case DeviceType_Floppy:
+                    pcszType = "Floppy";
+                    break;
+
+                default: break; /* Shut up MSC. */
+            }
+
+            pelmDevice->setAttribute("type", pcszType);
+
+            if (m->sv >= SettingsVersion_v1_15)
+                pelmDevice->setAttribute("hotpluggable", att.fHotPluggable);
+
+            pelmDevice->setAttribute("port", att.lPort);
+            pelmDevice->setAttribute("device", att.lDevice);
+
+            if (att.strBwGroup.length())
+                pelmDevice->setAttribute("bandwidthGroup", att.strBwGroup);
+
+            // attached image, if any
+            if (!att.uuid.isZero()
+                 && att.uuid.isValid()
+                 && (att.deviceType == DeviceType_HardDisk
+                      || !fSkipRemovableMedia
+                    )
+               )
+            {
+                xml::ElementNode *pelmImage = pelmDevice->createChild("Image");
+                pelmImage->setAttribute("uuid", att.uuid.toStringCurly());
+
+                // if caller wants a list of UUID elements, give it to them
+                if (pllElementsWithUuidAttributes)
+                    pllElementsWithUuidAttributes->push_back(pelmImage);
+            }
+            else if (    (m->sv >= SettingsVersion_v1_9)
+                      && (att.strHostDriveSrc.length())
+                    )
+                pelmDevice->createChild("HostDrive")->setAttribute("src", att.strHostDriveSrc);
+        }
+    }
+}
+
+/**
+ * Creates a \<Debugging\> node under elmParent and then writes out the XML
+ * keys under that. Called for both the \<Machine\> node and for snapshots.
+ *
+ * @param elmParent     Parent element.
+ * @param dbg           Debugging settings.
+ */
+void MachineConfigFile::buildDebuggingXML(xml::ElementNode &elmParent, const Debugging &dbg)
+{
+    if (m->sv < SettingsVersion_v1_13 || dbg.areDefaultSettings())
+        return;
+
+    xml::ElementNode *pElmDebugging = elmParent.createChild("Debugging");
+    xml::ElementNode *pElmTracing   = pElmDebugging->createChild("Tracing");
+    pElmTracing->setAttribute("enabled", dbg.fTracingEnabled);
+    pElmTracing->setAttribute("allowTracingToAccessVM", dbg.fAllowTracingToAccessVM);
+    pElmTracing->setAttribute("config", dbg.strTracingConfig);
+
+    xml::ElementNode *pElmGuestDebug = pElmDebugging->createChild("GuestDebug");
+    const char *pcszDebugProvider = NULL;
+    const char *pcszIoProvider = NULL;
+
+    switch (dbg.enmDbgProvider)
+    {
+        case GuestDebugProvider_None:    pcszDebugProvider = "None"; break;
+        case GuestDebugProvider_GDB:     pcszDebugProvider = "GDB";  break;
+        case GuestDebugProvider_KD:      pcszDebugProvider = "KD";   break;
+        default:         AssertFailed(); pcszDebugProvider = "None"; break;
+    }
+
+    switch (dbg.enmIoProvider)
+    {
+        case GuestDebugIoProvider_None:  pcszIoProvider = "None"; break;
+        case GuestDebugIoProvider_TCP:   pcszIoProvider = "TCP";  break;
+        case GuestDebugIoProvider_UDP:   pcszIoProvider = "UDP";  break;
+        case GuestDebugIoProvider_IPC:   pcszIoProvider = "IPC";  break;
+        default:         AssertFailed(); pcszIoProvider = "None"; break;
+    }
+
+    pElmGuestDebug->setAttribute("provider", pcszDebugProvider);
+    pElmGuestDebug->setAttribute("io",       pcszIoProvider);
+    pElmGuestDebug->setAttribute("address",  dbg.strAddress);
+    pElmGuestDebug->setAttribute("port",     dbg.ulPort);
+}
+
+/**
+ * Creates a \<Autostart\> node under elmParent and then writes out the XML
+ * keys under that. Called for both the \<Machine\> node and for snapshots.
+ *
+ * @param elmParent     Parent element.
+ * @param autostrt      Autostart settings.
+ */
+void MachineConfigFile::buildAutostartXML(xml::ElementNode &elmParent, const Autostart &autostrt)
+{
+    const char *pcszAutostop = NULL;
+
+    if (m->sv < SettingsVersion_v1_13 || autostrt.areDefaultSettings())
+        return;
+
+    xml::ElementNode *pElmAutostart = elmParent.createChild("Autostart");
+    pElmAutostart->setAttribute("enabled", autostrt.fAutostartEnabled);
+    pElmAutostart->setAttribute("delay", autostrt.uAutostartDelay);
+
+    switch (autostrt.enmAutostopType)
+    {
+        case AutostopType_Disabled:     pcszAutostop = "Disabled";     break;
+        case AutostopType_SaveState:    pcszAutostop = "SaveState";    break;
+        case AutostopType_PowerOff:     pcszAutostop = "PowerOff";     break;
+        case AutostopType_AcpiShutdown: pcszAutostop = "AcpiShutdown"; break;
+        default:         Assert(false); pcszAutostop = "Disabled";     break;
+    }
+    pElmAutostart->setAttribute("autostop", pcszAutostop);
+}
+
+void MachineConfigFile::buildRecordingXML(xml::ElementNode &elmParent, const RecordingSettings &recording)
+{
+    if (recording.areDefaultSettings()) /* Omit branch if we still have the default settings (i.e. nothing to save). */
+        return;
+
+    AssertReturnVoid(recording.mapScreens.size() <= 64); /* Make sure we never exceed the bitmap of 64 monitors. */
+
+    /* Note: Since settings 1.19 the recording settings have a dedicated XML branch outside of Hardware. */
+    if (m->sv >= SettingsVersion_v1_19 /* VBox >= 7.0 */)
+    {
+        /* Note: elmParent is Machine or Snapshot. */
+        xml::ElementNode *pelmRecording = elmParent.createChild("Recording");
+
+        if (!recordingSettings.common.areDefaultSettings())
+        {
+            pelmRecording->setAttribute("enabled", recording.common.fEnabled);
+        }
+
+        /* Only serialize screens which have non-default settings. */
+        uint32_t cScreensToWrite = 0;
+
+        RecordingScreenSettingsMap::const_iterator itScreen = recording.mapScreens.begin();
+        while (itScreen != recording.mapScreens.end())
+        {
+            if (!itScreen->second.areDefaultSettings())
+                cScreensToWrite++;
+            ++itScreen;
+        }
+
+        if (cScreensToWrite)
+            pelmRecording->setAttribute("screens", cScreensToWrite);
+
+        itScreen = recording.mapScreens.begin();
+        while (itScreen != recording.mapScreens.end())
+        {
+            if (!itScreen->second.areDefaultSettings()) /* Skip serializing screen settings which have default settings. */
+            {
+                xml::ElementNode *pelmScreen = pelmRecording->createChild("Screen");
+
+                pelmScreen->setAttribute("id",                  itScreen->first); /* The key equals the monitor ID. */
+                pelmScreen->setAttribute("enabled",             itScreen->second.fEnabled);
+                com::Utf8Str strTemp;
+                RecordingScreenSettings::featuresToString(itScreen->second.featureMap, strTemp);
+                pelmScreen->setAttribute("featuresEnabled",     strTemp);
+                if (itScreen->second.ulMaxTimeS)
+                    pelmScreen->setAttribute("maxTimeS",        itScreen->second.ulMaxTimeS);
+                if (itScreen->second.strOptions.isNotEmpty())
+                    pelmScreen->setAttributePath("options",     itScreen->second.strOptions);
+                pelmScreen->setAttribute("dest",                itScreen->second.enmDest);
+                if (!itScreen->second.File.strName.isEmpty())
+                    pelmScreen->setAttributePath("file",        itScreen->second.File.strName);
+                if (itScreen->second.File.ulMaxSizeMB)
+                    pelmScreen->setAttribute("maxSizeMB",       itScreen->second.File.ulMaxSizeMB);
+
+                RecordingScreenSettings::videoCodecToString(itScreen->second.Video.enmCodec, strTemp);
+                pelmScreen->setAttribute("videoCodec",          strTemp);
+                if (itScreen->second.Video.enmDeadline != RecordingCodecDeadline_Default)
+                    pelmScreen->setAttribute("videoDeadline",   itScreen->second.Video.enmDeadline);
+                if (itScreen->second.Video.enmRateCtlMode != RecordingRateControlMode_VBR) /* Is default. */
+                    pelmScreen->setAttribute("videoRateCtlMode", itScreen->second.Video.enmRateCtlMode);
+                if (itScreen->second.Video.enmScalingMode != RecordingVideoScalingMode_None)
+                    pelmScreen->setAttribute("videoScalingMode",itScreen->second.Video.enmScalingMode);
+                if (   itScreen->second.Video.ulWidth  != 1024
+                    || itScreen->second.Video.ulHeight != 768)
+                {
+                    pelmScreen->setAttribute("horzRes",         itScreen->second.Video.ulWidth);
+                    pelmScreen->setAttribute("vertRes",         itScreen->second.Video.ulHeight);
+                }
+                if (itScreen->second.Video.ulRate != 512)
+                    pelmScreen->setAttribute("rateKbps",        itScreen->second.Video.ulRate);
+                if (itScreen->second.Video.ulFPS)
+                    pelmScreen->setAttribute("fps",             itScreen->second.Video.ulFPS);
+
+                RecordingScreenSettings::audioCodecToString(itScreen->second.Audio.enmCodec, strTemp);
+                pelmScreen->setAttribute("audioCodec",          strTemp);
+                if (itScreen->second.Audio.enmDeadline != RecordingCodecDeadline_Default)
+                    pelmScreen->setAttribute("audioDeadline",   itScreen->second.Audio.enmDeadline);
+                if (itScreen->second.Audio.enmRateCtlMode != RecordingRateControlMode_VBR) /* Is default. */
+                    pelmScreen->setAttribute("audioRateCtlMode", itScreen->second.Audio.enmRateCtlMode);
+                if (itScreen->second.Audio.uHz != 22050)
+                    pelmScreen->setAttribute("audioHz",         itScreen->second.Audio.uHz);
+                if (itScreen->second.Audio.cBits != 16)
+                    pelmScreen->setAttribute("audioBits",       itScreen->second.Audio.cBits);
+                if (itScreen->second.Audio.cChannels != 2)
+                    pelmScreen->setAttribute("audioChannels",   itScreen->second.Audio.cChannels);
+            }
+            ++itScreen;
+        }
+    }
+    else if (   m->sv >= SettingsVersion_v1_14
+             && m->sv <  SettingsVersion_v1_19 /* VBox < 7.0 */)
+    {
+        /* Note: elmParent is Hardware or Snapshot. */
+        xml::ElementNode *pelmVideoCapture = elmParent.createChild("VideoCapture");
+
+        if (!recordingSettings.common.areDefaultSettings())
+        {
+            pelmVideoCapture->setAttribute("enabled", recording.common.fEnabled);
+        }
+
+        /* Convert the enabled screens to the former uint64_t bit array and vice versa. */
+        uint64_t uScreensBitmap = 0;
+        RecordingScreenSettingsMap::const_iterator itScreen = recording.mapScreens.begin();
+        while (itScreen != recording.mapScreens.end())
+        {
+            if (itScreen->second.fEnabled)
+                uScreensBitmap |= RT_BIT_64(itScreen->first);
+            ++itScreen;
+        }
+
+        if (uScreensBitmap)
+            pelmVideoCapture->setAttribute("screens",      uScreensBitmap);
+
+        Assert(recording.mapScreens.size());
+        const RecordingScreenSettingsMap::const_iterator itScreen0Settings = recording.mapScreens.find(0);
+        Assert(itScreen0Settings != recording.mapScreens.end());
+
+        if (itScreen0Settings->second.ulMaxTimeS)
+            pelmVideoCapture->setAttribute("maxTime",      itScreen0Settings->second.ulMaxTimeS);
+        if (itScreen0Settings->second.strOptions.isNotEmpty())
+            pelmVideoCapture->setAttributePath("options",  itScreen0Settings->second.strOptions);
+
+        if (!itScreen0Settings->second.File.strName.isEmpty())
+            pelmVideoCapture->setAttributePath("file",     itScreen0Settings->second.File.strName);
+        if (itScreen0Settings->second.File.ulMaxSizeMB)
+            pelmVideoCapture->setAttribute("maxSize",      itScreen0Settings->second.File.ulMaxSizeMB);
+
+        if (   itScreen0Settings->second.Video.ulWidth  != 1024
+            || itScreen0Settings->second.Video.ulHeight != 768)
+        {
+            pelmVideoCapture->setAttribute("horzRes",      itScreen0Settings->second.Video.ulWidth);
+            pelmVideoCapture->setAttribute("vertRes",      itScreen0Settings->second.Video.ulHeight);
+        }
+        if (itScreen0Settings->second.Video.ulRate != 512)
+            pelmVideoCapture->setAttribute("rate",         itScreen0Settings->second.Video.ulRate);
+        if (itScreen0Settings->second.Video.ulFPS)
+            pelmVideoCapture->setAttribute("fps",          itScreen0Settings->second.Video.ulFPS);
+    }
+}
+
+/**
+ * Creates a \<Groups\> node under elmParent and then writes out the XML
+ * keys under that. Called for the \<Machine\> node only.
+ *
+ * @param elmParent     Parent element.
+ * @param llGroups      Groups list.
+ */
+void MachineConfigFile::buildGroupsXML(xml::ElementNode &elmParent, const StringsList &llGroups)
+{
+    if (   m->sv < SettingsVersion_v1_13 || llGroups.size() == 0
+        || (llGroups.size() == 1 && llGroups.front() == "/"))
+        return;
+
+    xml::ElementNode *pElmGroups = elmParent.createChild("Groups");
+    for (StringsList::const_iterator it = llGroups.begin();
+         it != llGroups.end();
+         ++it)
+    {
+        const Utf8Str &group = *it;
+        xml::ElementNode *pElmGroup = pElmGroups->createChild("Group");
+        pElmGroup->setAttribute("name", group);
+    }
+}
+
+/**
+ * Writes a single snapshot into the DOM tree. Initially this gets called from
+ * MachineConfigFile::write() for the root snapshot of a machine, if present;
+ * elmParent then points to the \<Snapshots\> node under the \<Machine\> node
+ * to which \<Snapshot\> must be added. This may then continue processing the
+ * child snapshots.
+ *
+ * @param elmParent
+ * @param snap
+ */
+void MachineConfigFile::buildSnapshotXML(xml::ElementNode &elmParent,
+                                         const Snapshot &snap)
+{
+    std::list<const Snapshot *> llSettingsTodo;
+    llSettingsTodo.push_back(&snap);
+    std::list<xml::ElementNode *> llElementsTodo;
+    llElementsTodo.push_back(&elmParent);
+    std::list<uint32_t> llDepthsTodo;
+    llDepthsTodo.push_back(1);
+
+    while (llSettingsTodo.size() > 0)
+    {
+        const Snapshot *pSnap = llSettingsTodo.front();
+        llSettingsTodo.pop_front();
+        xml::ElementNode *pElement = llElementsTodo.front();
+        llElementsTodo.pop_front();
+        uint32_t depth = llDepthsTodo.front();
+        llDepthsTodo.pop_front();
+
+        if (depth > SETTINGS_SNAPSHOT_DEPTH_MAX)
+            throw ConfigFileError(this, NULL, N_("Maximum snapshot tree depth of %u exceeded"), SETTINGS_SNAPSHOT_DEPTH_MAX);
+
+        xml::ElementNode *pelmSnapshot = pElement->createChild("Snapshot");
+
+        pelmSnapshot->setAttribute("uuid", pSnap->uuid.toStringCurly());
+        pelmSnapshot->setAttribute("name", pSnap->strName);
+        pelmSnapshot->setAttribute("timeStamp", stringifyTimestamp(pSnap->timestamp));
+
+        if (pSnap->strStateFile.length())
+            pelmSnapshot->setAttributePath("stateFile", pSnap->strStateFile);
+
+        if (pSnap->strDescription.length())
+            pelmSnapshot->createChild("Description")->addContent(pSnap->strDescription);
+
+        // We only skip removable media for OVF, but OVF never includes snapshots.
+        buildHardwareXML(*pelmSnapshot, pSnap->hardware, 0 /* fl */, NULL /* pllElementsWithUuidAttributes */);
+        buildDebuggingXML(*pelmSnapshot, pSnap->debugging);
+        buildAutostartXML(*pelmSnapshot, pSnap->autostart);
+        buildRecordingXML(*pelmSnapshot, pSnap->recordingSettings);
+        // note: Groups exist only for Machine, not for Snapshot
+
+        if (pSnap->llChildSnapshots.size())
+        {
+            xml::ElementNode *pelmChildren = pelmSnapshot->createChild("Snapshots");
+            for (SnapshotsList::const_iterator it = pSnap->llChildSnapshots.begin();
+                it != pSnap->llChildSnapshots.end();
+                ++it)
+            {
+                llSettingsTodo.push_back(&*it);
+                llElementsTodo.push_back(pelmChildren);
+                llDepthsTodo.push_back(depth + 1);
+            }
+        }
+    }
+}
+
+/**
+ * Builds the XML DOM tree for the machine config under the given XML element.
+ *
+ * This has been separated out from write() so it can be called from elsewhere,
+ * such as the OVF code, to build machine XML in an existing XML tree.
+ *
+ * As a result, this gets called from two locations:
+ *
+ *  --  MachineConfigFile::write();
+ *
+ *  --  Appliance::buildXMLForOneVirtualSystem()
+ *
+ * In fl, the following flag bits are recognized:
+ *
+ *  --  BuildMachineXML_MediaRegistry: If set, the machine's media registry will
+ *      be written, if present. This is not set when called from OVF because OVF
+ *      has its own variant of a media registry. This flag is ignored unless the
+ *      settings version is at least v1.11 (VirtualBox 4.0).
+ *
+ *  --  BuildMachineXML_IncludeSnapshots: If set, descend into the snapshots tree
+ *      of the machine and write out \<Snapshot\> and possibly more snapshots under
+ *      that, if snapshots are present. Otherwise all snapshots are suppressed
+ *      (when called from OVF).
+ *
+ *  --  BuildMachineXML_WriteVBoxVersionAttribute: If set, add a settingsVersion
+ *      attribute to the machine tag with the vbox settings version. This is for
+ *      the OVF export case in which we don't have the settings version set in
+ *      the root element.
+ *
+ *  --  BuildMachineXML_SkipRemovableMedia: If set, removable media attachments
+ *      (DVDs, floppies) are silently skipped. This is for the OVF export case
+ *      until we support copying ISO and RAW media as well.  This flag is ignored
+ *      unless the settings version is at least v1.9, which is always the case
+ *      when this gets called for OVF export.
+ *
+ * --   BuildMachineXML_SuppressSavedState: If set, the Machine/stateFile
+ *      attribute is never set. This is also for the OVF export case because we
+ *      cannot save states with OVF.
+ *
+ * @param elmMachine XML \<Machine\> element to add attributes and elements to.
+ * @param fl Flags.
+ * @param pllElementsWithUuidAttributes pointer to list that should receive UUID elements or NULL;
+ *        see buildStorageControllersXML() for details.
+ */
+void MachineConfigFile::buildMachineXML(xml::ElementNode &elmMachine,
+                                        uint32_t fl,
+                                        std::list<xml::ElementNode*> *pllElementsWithUuidAttributes)
+{
+    if (fl & BuildMachineXML_WriteVBoxVersionAttribute)
+    {
+        // add settings version attribute to machine element
+        setVersionAttribute(elmMachine);
+        LogRel(("Exporting settings file \"%s\" with version \"%s\"\n", m->strFilename.c_str(), m->strSettingsVersionFull.c_str()));
+    }
+
+    elmMachine.setAttribute("uuid", uuid.toStringCurly());
+    elmMachine.setAttribute("name", machineUserData.strName);
+    if (machineUserData.fDirectoryIncludesUUID)
+        elmMachine.setAttribute("directoryIncludesUUID", machineUserData.fDirectoryIncludesUUID);
+    if (!machineUserData.fNameSync)
+        elmMachine.setAttribute("nameSync", machineUserData.fNameSync);
+    if (machineUserData.strDescription.length())
+        elmMachine.createChild("Description")->addContent(machineUserData.strDescription);
+    elmMachine.setAttribute("OSType", machineUserData.strOsType);
+
+
+    if (m->sv >= SettingsVersion_v1_19)
+    {
+        if (strStateKeyId.length())
+            elmMachine.setAttribute("stateKeyId", strStateKeyId);
+        if (strStateKeyStore.length())
+            elmMachine.setAttribute("stateKeyStore", strStateKeyStore);
+        if (strLogKeyId.length())
+            elmMachine.setAttribute("logKeyId", strLogKeyId);
+        if (strLogKeyStore.length())
+            elmMachine.setAttribute("logKeyStore", strLogKeyStore);
+    }
+    if (    strStateFile.length()
+         && !(fl & BuildMachineXML_SuppressSavedState)
+       )
+        elmMachine.setAttributePath("stateFile", strStateFile);
+
+    if ((fl & BuildMachineXML_IncludeSnapshots)
+         && !uuidCurrentSnapshot.isZero()
+         && uuidCurrentSnapshot.isValid())
+        elmMachine.setAttribute("currentSnapshot", uuidCurrentSnapshot.toStringCurly());
+
+    if (machineUserData.strSnapshotFolder.length())
+        elmMachine.setAttributePath("snapshotFolder", machineUserData.strSnapshotFolder);
+    if (!fCurrentStateModified)
+        elmMachine.setAttribute("currentStateModified", fCurrentStateModified);
+    elmMachine.setAttribute("lastStateChange", stringifyTimestamp(timeLastStateChange));
+    if (fAborted)
+        elmMachine.setAttribute("aborted", fAborted);
+
+    switch (machineUserData.enmVMPriority)
+    {
+        case VMProcPriority_Flat:
+            elmMachine.setAttribute("processPriority", "Flat");
+            break;
+        case VMProcPriority_Low:
+            elmMachine.setAttribute("processPriority", "Low");
+            break;
+        case VMProcPriority_Normal:
+            elmMachine.setAttribute("processPriority", "Normal");
+            break;
+        case VMProcPriority_High:
+            elmMachine.setAttribute("processPriority", "High");
+            break;
+        default:
+            break;
+    }
+    // Please keep the icon last so that one doesn't have to check if there
+    // is anything in the line after this very long attribute in the XML.
+    if (machineUserData.ovIcon.size())
+    {
+        Utf8Str strIcon;
+        toBase64(strIcon, machineUserData.ovIcon);
+        elmMachine.setAttribute("icon", strIcon);
+    }
+    if (    m->sv >= SettingsVersion_v1_9
+        &&  (   machineUserData.fTeleporterEnabled
+            ||  machineUserData.uTeleporterPort
+            ||  !machineUserData.strTeleporterAddress.isEmpty()
+            ||  !machineUserData.strTeleporterPassword.isEmpty()
+            )
+       )
+    {
+        xml::ElementNode *pelmTeleporter = elmMachine.createChild("Teleporter");
+        pelmTeleporter->setAttribute("enabled", machineUserData.fTeleporterEnabled);
+        pelmTeleporter->setAttribute("port", machineUserData.uTeleporterPort);
+        pelmTeleporter->setAttribute("address", machineUserData.strTeleporterAddress);
+        pelmTeleporter->setAttribute("password", machineUserData.strTeleporterPassword);
+    }
+
+    if (    (fl & BuildMachineXML_MediaRegistry)
+         && (m->sv >= SettingsVersion_v1_11)
+       )
+        buildMediaRegistry(elmMachine, mediaRegistry);
+
+    buildExtraData(elmMachine, mapExtraDataItems);
+
+    if (    (fl & BuildMachineXML_IncludeSnapshots)
+         && llFirstSnapshot.size())
+        buildSnapshotXML(elmMachine, llFirstSnapshot.front());
+
+    buildHardwareXML(elmMachine, hardwareMachine, fl, pllElementsWithUuidAttributes);
+    buildDebuggingXML(elmMachine, debugging);
+    buildAutostartXML(elmMachine, autostart);
+
+    /* Note: Must come *after* buildHardwareXML(), as the "Hardware" branch is needed. */
+    if (   m->sv >= SettingsVersion_v1_14
+        && m->sv  < SettingsVersion_v1_19) /* < VBox 7.0. */
+    {
+        xml::ElementNode *pelHardware = unconst(elmMachine.findChildElement("Hardware"));
+        if (pelHardware)
+            buildRecordingXML(*pelHardware, recordingSettings);
+    }
+    else if (m->sv >= SettingsVersion_v1_19) /* Now lives outside of "Hardware", in "Machine". */
+        buildRecordingXML(elmMachine, recordingSettings);
+
+    buildGroupsXML(elmMachine, machineUserData.llGroups);
+}
+
+ /**
+ * Builds encrypted config.
+ *
+ * @sa MachineConfigFile::buildMachineXML
+ */
+void MachineConfigFile::buildMachineEncryptedXML(xml::ElementNode &elmMachine,
+                                                 uint32_t fl,
+                                                 std::list<xml::ElementNode*> *pllElementsWithUuidAttributes,
+                                                 PCVBOXCRYPTOIF pCryptoIf,
+                                                 const char *pszPassword = NULL)
+{
+    if (   !pszPassword
+        || !pCryptoIf)
+        throw ConfigFileError(this, &elmMachine, N_("Password is required"));
+
+    xml::Document *pDoc = new xml::Document;
+    xml::ElementNode *pelmRoot = pDoc->createRootElement("Machine");
+    pelmRoot->setAttribute("xmlns", VBOX_XML_NAMESPACE);
+    // Have the code for producing a proper schema reference. Not used by most
+    // tools, so don't bother doing it. The schema is not on the server anyway.
+#ifdef VBOX_WITH_SETTINGS_SCHEMA
+    pelmRoot->setAttribute("xmlns:xsi", "http://www.w3.org/2001/XMLSchema-instance");
+    pelmRoot->setAttribute("xsi:schemaLocation", VBOX_XML_NAMESPACE " " VBOX_XML_SCHEMA);
+#endif
+
+    buildMachineXML(*pelmRoot, fl, pllElementsWithUuidAttributes);
+    xml::XmlStringWriter writer;
+    com::Utf8Str strMachineXml;
+    int vrc = writer.write(*pDoc, &strMachineXml);
+    delete pDoc;
+    if (RT_SUCCESS(vrc))
+    {
+        VBOXCRYPTOCTX hCryptoCtx;
+        if (strKeyStore.isEmpty())
+        {
+            vrc = pCryptoIf->pfnCryptoCtxCreate("AES-GCM256", pszPassword, &hCryptoCtx);
+            if (RT_SUCCESS(vrc))
+            {
+                char *pszNewKeyStore;
+                vrc = pCryptoIf->pfnCryptoCtxSave(hCryptoCtx, &pszNewKeyStore);
+                if (RT_SUCCESS(vrc))
+                {
+                    strKeyStore = pszNewKeyStore;
+                    RTStrFree(pszNewKeyStore);
+                }
+                else
+                    pCryptoIf->pfnCryptoCtxDestroy(hCryptoCtx);
+            }
+        }
+        else
+            vrc = pCryptoIf->pfnCryptoCtxLoad(strKeyStore.c_str(), pszPassword, &hCryptoCtx);
+        if (RT_SUCCESS(vrc))
+        {
+            IconBlob abEncrypted;
+            size_t cbEncrypted = 0;
+            vrc = pCryptoIf->pfnCryptoCtxQueryEncryptedSize(hCryptoCtx, strMachineXml.length(), &cbEncrypted);
+            if (RT_SUCCESS(vrc))
+            {
+                abEncrypted.resize(cbEncrypted);
+                vrc = pCryptoIf->pfnCryptoCtxEncrypt(hCryptoCtx, false /*fPartial*/, NULL /*pvIV*/, 0 /*cbIV*/,
+                                                     strMachineXml.c_str(), strMachineXml.length(),
+                                                     uuid.raw(), sizeof(RTUUID),
+                                                     &abEncrypted[0], abEncrypted.size(), &cbEncrypted);
+                int vrc2 = pCryptoIf->pfnCryptoCtxDestroy(hCryptoCtx);
+                AssertRC(vrc2);
+                if (RT_SUCCESS(vrc))
+                {
+                    abEncrypted.resize(cbEncrypted);
+                    toBase64(strMachineXml, abEncrypted);
+                    elmMachine.setAttribute("uuid", uuid.toStringCurly());
+                    elmMachine.setAttribute("keyId", strKeyId);
+                    elmMachine.setAttribute("keyStore", strKeyStore);
+                    elmMachine.setContent(strMachineXml.c_str());
+                }
+            }
+        }
+
+        if (RT_FAILURE(vrc))
+            throw ConfigFileError(this, &elmMachine, N_("Creating machine encrypted xml failed. (%Rrc)"), vrc);
+    }
+    else
+        throw ConfigFileError(this, &elmMachine, N_("Creating machine xml failed. (%Rrc)"), vrc);
+}
+
+/**
+ * Returns true only if the given AudioDriverType is supported on
+ * the current host platform. For example, this would return false
+ * for AudioDriverType_DirectSound when compiled on a Linux host.
+ *
+*  @return @c true if the current host supports the driver, @c false if not.
+ * @param enmDrvType            AudioDriverType_* enum to test.
+ */
+/*static*/
+bool MachineConfigFile::isAudioDriverAllowedOnThisHost(AudioDriverType_T enmDrvType)
+{
+    switch (enmDrvType)
+    {
+        case AudioDriverType_Default:
+            RT_FALL_THROUGH();
+        case AudioDriverType_Null:
+            return true; /* Default and Null audio are always allowed. */
+#ifdef RT_OS_WINDOWS
+        case AudioDriverType_WAS:
+            /* We only support WAS on systems we tested so far (Vista+). */
+            if (RTSystemGetNtVersion() < RTSYSTEM_MAKE_NT_VERSION(6,1,0))
+                break;
+            RT_FALL_THROUGH();
+        case AudioDriverType_DirectSound:
+#endif
+#ifdef VBOX_WITH_AUDIO_OSS
+        case AudioDriverType_OSS:
+#endif
+#ifdef VBOX_WITH_AUDIO_ALSA
+        case AudioDriverType_ALSA:
+#endif
+#ifdef VBOX_WITH_AUDIO_PULSE
+        case AudioDriverType_Pulse:
+#endif
+#ifdef RT_OS_DARWIN
+        case AudioDriverType_CoreAudio:
+#endif
+#ifdef RT_OS_OS2
+        case AudioDriverType_MMPM:
+#endif
+            return true;
+        default: break; /* Shut up MSC. */
+    }
+
+    return false;
+}
+
+/**
+ * Returns the AudioDriverType_* which should be used by default on this
+ * host platform. On Linux, this will check at runtime whether PulseAudio
+ * or ALSA are actually supported on the first call.
+ *
+ * When more than one supported audio stack is available, choose the most suited
+ * (probably newest in most cases) one.
+ *
+ * @return Default audio driver type for this host platform.
+ */
+/*static*/
+AudioDriverType_T MachineConfigFile::getHostDefaultAudioDriver()
+{
+#if defined(RT_OS_WINDOWS)
+    if (RTSystemGetNtVersion() >= RTSYSTEM_MAKE_NT_VERSION(6,1,0))
+        return AudioDriverType_WAS;
+    return AudioDriverType_DirectSound;
+
+#elif defined(RT_OS_LINUX)
+    /* On Linux, we need to check at runtime what's actually supported.
+     * Descending precedence. */
+    static RTCLockMtx s_mtx;
+    static AudioDriverType_T s_enmLinuxDriver = AudioDriverType_Null;
+    RTCLock lock(s_mtx);
+    if (s_enmLinuxDriver == AudioDriverType_Null) /* Already determined from a former run? */
+    {
+# ifdef VBOX_WITH_AUDIO_PULSE
+        /* Check for the pulse library & that the PulseAudio daemon is running. */
+        if (   (   RTProcIsRunningByName("pulseaudio")
+                /* We also use the PulseAudio backend when we find pipewire-pulse running, which
+                 * acts as a PulseAudio-compatible daemon for Pipewire-enabled applications. See @ticketref{21575} */
+                || RTProcIsRunningByName("pipewire-pulse"))
+            && RTLdrIsLoadable("libpulse.so.0"))
+        {
+            s_enmLinuxDriver = AudioDriverType_Pulse;
+        }
+#endif /* VBOX_WITH_AUDIO_PULSE */
+
+# ifdef VBOX_WITH_AUDIO_ALSA
+        if (s_enmLinuxDriver == AudioDriverType_Null)
+        {
+            /* Check if we can load the ALSA library */
+            if (RTLdrIsLoadable("libasound.so.2"))
+                s_enmLinuxDriver = AudioDriverType_ALSA;
+        }
+# endif /* VBOX_WITH_AUDIO_ALSA */
+
+# ifdef VBOX_WITH_AUDIO_OSS
+        if (s_enmLinuxDriver == AudioDriverType_Null)
+            s_enmLinuxDriver = AudioDriverType_OSS;
+# endif /* VBOX_WITH_AUDIO_OSS */
+    }
+    return s_enmLinuxDriver;
+
+#elif defined(RT_OS_DARWIN)
+    return AudioDriverType_CoreAudio;
+
+#elif defined(RT_OS_OS2)
+    return AudioDriverType_MMPM;
+
+#else /* All other platforms. */
+# ifdef VBOX_WITH_AUDIO_OSS
+    return AudioDriverType_OSS;
+# else
+    /* Return NULL driver as a fallback if nothing of the above is available. */
+    return AudioDriverType_Null;
+# endif
+#endif
+}
+
+/**
+ * Called from write() before calling ConfigFileBase::createStubDocument().
+ * This adjusts the settings version in m->sv if incompatible settings require
+ * a settings bump, whereas otherwise we try to preserve the settings version
+ * to avoid breaking compatibility with older versions.
+ *
+ * We do the checks in here in reverse order: newest first, oldest last, so
+ * that we avoid unnecessary checks since some of these are expensive.
+ */
+void MachineConfigFile::bumpSettingsVersionIfNeeded()
+{
+    if (m->sv < SettingsVersion_v1_19)
+    {
+        // VirtualBox 7.0 adds iommu device and full VM encryption.
+        if (   hardwareMachine.iommuType != IommuType_None
+            || strKeyId.isNotEmpty()
+            || strKeyStore.isNotEmpty()
+            || strStateKeyId.isNotEmpty()
+            || strStateKeyStore.isNotEmpty()
+            || hardwareMachine.nvramSettings.strKeyId.isNotEmpty()
+            || hardwareMachine.nvramSettings.strKeyStore.isNotEmpty()
+            /* Default for newly created VMs in VBox 7.0.
+             * Older VMs might have a specific audio driver set (also for VMs created with < VBox 7.0). */
+            || hardwareMachine.audioAdapter.driverType == AudioDriverType_Default
+            || recordingSettings.areDefaultSettings() == false
+            || strLogKeyId.isNotEmpty()
+            || strLogKeyStore.isEmpty())
+        {
+            m->sv = SettingsVersion_v1_19;
+            return;
+        }
+
+        // VirtualBox 7.0 adds a Trusted Platform Module.
+        if (   hardwareMachine.tpmSettings.tpmType != TpmType_None
+            || hardwareMachine.tpmSettings.strLocation.isNotEmpty())
+        {
+            m->sv = SettingsVersion_v1_19;
+            return;
+        }
+
+        NetworkAdaptersList::const_iterator netit;
+        for (netit = hardwareMachine.llNetworkAdapters.begin();
+             netit != hardwareMachine.llNetworkAdapters.end();
+             ++netit)
+        {
+            // VirtualBox 7.0 adds a flag if NAT can reach localhost.
+            if (   netit->fEnabled
+                && netit->mode == NetworkAttachmentType_NAT
+                && !netit->nat.fLocalhostReachable)
+            {
+                m->sv = SettingsVersion_v1_19;
+                break;
+            }
+
+#ifdef VBOX_WITH_VMNET
+            // VirtualBox 7.0 adds a host-only network attachment.
+            if (netit->mode == NetworkAttachmentType_HostOnlyNetwork)
+            {
+                m->sv = SettingsVersion_v1_19;
+                break;
+            }
+#endif /* VBOX_WITH_VMNET */
+        }
+
+        // VirtualBox 7.0 adds guest debug settings.
+        if (   debugging.enmDbgProvider != GuestDebugProvider_None
+            || debugging.enmIoProvider != GuestDebugIoProvider_None
+            || debugging.strAddress.isNotEmpty()
+            || debugging.ulPort != 0)
+        {
+            m->sv = SettingsVersion_v1_19;
+            return;
+        }
+    }
+
+    if (m->sv < SettingsVersion_v1_18)
+    {
+        if (!hardwareMachine.nvramSettings.strNvramPath.isEmpty())
+        {
+            m->sv = SettingsVersion_v1_18;
+            return;
+        }
+
+        // VirtualBox 6.1 adds AMD-V virtualized VMSAVE/VMLOAD setting.
+        if (hardwareMachine.fVirtVmsaveVmload == false)
+        {
+            m->sv = SettingsVersion_v1_18;
+            return;
+        }
+
+        // VirtualBox 6.1 adds a virtio-scsi storage controller.
+        for (StorageControllersList::const_iterator it = hardwareMachine.storage.llStorageControllers.begin();
+             it != hardwareMachine.storage.llStorageControllers.end();
+             ++it)
+        {
+            const StorageController &sctl = *it;
+
+            if (sctl.controllerType == StorageControllerType_VirtioSCSI)
+            {
+                m->sv = SettingsVersion_v1_18;
+                return;
+            }
+        }
+
+#ifdef VBOX_WITH_CLOUD_NET
+        NetworkAdaptersList::const_iterator netit;
+        for (netit = hardwareMachine.llNetworkAdapters.begin();
+             netit != hardwareMachine.llNetworkAdapters.end();
+             ++netit)
+        {
+            // VirtualBox 6.1 adds support for cloud networks.
+            if (   netit->fEnabled
+                && netit->mode == NetworkAttachmentType_Cloud)
+            {
+                m->sv = SettingsVersion_v1_18;
+                break;
+            }
+
+        }
+#endif /* VBOX_WITH_CLOUD_NET */
+    }
+
+    if (m->sv < SettingsVersion_v1_17)
+    {
+        if (machineUserData.enmVMPriority != VMProcPriority_Default)
+        {
+            m->sv = SettingsVersion_v1_17;
+            return;
+        }
+
+        // VirtualBox 6.0 adds nested hardware virtualization, using native API (NEM).
+        if (   hardwareMachine.fNestedHWVirt
+            || hardwareMachine.fUseNativeApi)
+        {
+            m->sv = SettingsVersion_v1_17;
+            return;
+        }
+        if (hardwareMachine.llSharedFolders.size())
+            for (SharedFoldersList::const_iterator it = hardwareMachine.llSharedFolders.begin();
+                 it != hardwareMachine.llSharedFolders.end();
+                 ++it)
+                if (it->strAutoMountPoint.isNotEmpty())
+                {
+                    m->sv = SettingsVersion_v1_17;
+                    return;
+                }
+
+        /*
+         * Check if any serial port uses a non 16550A serial port.
+         */
+        for (SerialPortsList::const_iterator it = hardwareMachine.llSerialPorts.begin();
+             it != hardwareMachine.llSerialPorts.end();
+             ++it)
+        {
+            const SerialPort &port = *it;
+            if (port.uartType != UartType_U16550A)
+            {
+                m->sv = SettingsVersion_v1_17;
+                return;
+            }
+        }
+    }
+
+    if (m->sv < SettingsVersion_v1_16)
+    {
+        // VirtualBox 5.1 adds a NVMe storage controller, paravirt debug
+        // options, cpu profile, APIC settings (CPU capability and BIOS).
+
+        if (   hardwareMachine.strParavirtDebug.isNotEmpty()
+            || (!hardwareMachine.strCpuProfile.equals("host") && hardwareMachine.strCpuProfile.isNotEmpty())
+            || hardwareMachine.biosSettings.apicMode != APICMode_APIC
+            || !hardwareMachine.fAPIC
+            || hardwareMachine.fX2APIC
+            || hardwareMachine.fIBPBOnVMExit
+            || hardwareMachine.fIBPBOnVMEntry
+            || hardwareMachine.fSpecCtrl
+            || hardwareMachine.fSpecCtrlByHost
+            || !hardwareMachine.fL1DFlushOnSched
+            || hardwareMachine.fL1DFlushOnVMEntry
+            || !hardwareMachine.fMDSClearOnSched
+            || hardwareMachine.fMDSClearOnVMEntry)
+        {
+            m->sv = SettingsVersion_v1_16;
+            return;
+        }
+
+        for (StorageControllersList::const_iterator it = hardwareMachine.storage.llStorageControllers.begin();
+             it != hardwareMachine.storage.llStorageControllers.end();
+             ++it)
+        {
+            const StorageController &sctl = *it;
+
+            if (sctl.controllerType == StorageControllerType_NVMe)
+            {
+                m->sv = SettingsVersion_v1_16;
+                return;
+            }
+        }
+
+        for (CpuIdLeafsList::const_iterator it = hardwareMachine.llCpuIdLeafs.begin();
+             it != hardwareMachine.llCpuIdLeafs.end();
+             ++it)
+            if (it->idxSub != 0)
+            {
+                m->sv = SettingsVersion_v1_16;
+                return;
+            }
+    }
+
+    if (m->sv < SettingsVersion_v1_15)
+    {
+        // VirtualBox 5.0 adds paravirt providers, explicit AHCI port hotplug
+        // setting, USB storage controller, xHCI, serial port TCP backend
+        // and VM process priority.
+
+        /*
+         * Check simple configuration bits first, loopy stuff afterwards.
+         */
+        if (   hardwareMachine.paravirtProvider != ParavirtProvider_Legacy
+            || hardwareMachine.uCpuIdPortabilityLevel != 0)
+        {
+            m->sv = SettingsVersion_v1_15;
+            return;
+        }
+
+        /*
+         * Check whether the hotpluggable flag of all storage devices differs
+         * from the default for old settings.
+         * AHCI ports are hotpluggable by default every other device is not.
+         * Also check if there are USB storage controllers.
+         */
+        for (StorageControllersList::const_iterator it = hardwareMachine.storage.llStorageControllers.begin();
+             it != hardwareMachine.storage.llStorageControllers.end();
+             ++it)
+        {
+            const StorageController &sctl = *it;
+
+            if (sctl.controllerType == StorageControllerType_USB)
+            {
+                m->sv = SettingsVersion_v1_15;
+                return;
+            }
+
+            for (AttachedDevicesList::const_iterator it2 = sctl.llAttachedDevices.begin();
+                 it2 != sctl.llAttachedDevices.end();
+                 ++it2)
+            {
+                const AttachedDevice &att = *it2;
+
+                if (   (   att.fHotPluggable
+                        && sctl.controllerType != StorageControllerType_IntelAhci)
+                    || (   !att.fHotPluggable
+                        && sctl.controllerType == StorageControllerType_IntelAhci))
+                {
+                    m->sv = SettingsVersion_v1_15;
+                    return;
+                }
+            }
+        }
+
+        /*
+         * Check if there is an xHCI (USB3) USB controller.
+         */
+        for (USBControllerList::const_iterator it = hardwareMachine.usbSettings.llUSBControllers.begin();
+             it != hardwareMachine.usbSettings.llUSBControllers.end();
+             ++it)
+        {
+            const USBController &ctrl = *it;
+            if (ctrl.enmType == USBControllerType_XHCI)
+            {
+                m->sv = SettingsVersion_v1_15;
+                return;
+            }
+        }
+
+        /*
+         * Check if any serial port uses the TCP backend.
+         */
+        for (SerialPortsList::const_iterator it = hardwareMachine.llSerialPorts.begin();
+             it != hardwareMachine.llSerialPorts.end();
+             ++it)
+        {
+            const SerialPort &port = *it;
+            if (port.portMode == PortMode_TCP)
+            {
+                m->sv = SettingsVersion_v1_15;
+                return;
+            }
+        }
+    }
+
+    if (m->sv < SettingsVersion_v1_14)
+    {
+        // VirtualBox 4.3 adds default frontend setting, graphics controller
+        // setting, explicit long mode setting, (video) capturing and NAT networking.
+        if (   !hardwareMachine.strDefaultFrontend.isEmpty()
+            || hardwareMachine.graphicsAdapter.graphicsControllerType != GraphicsControllerType_VBoxVGA
+            || hardwareMachine.enmLongMode != Hardware::LongMode_Legacy
+            || machineUserData.ovIcon.size() > 0
+            || recordingSettings.common.fEnabled)
+        {
+            m->sv = SettingsVersion_v1_14;
+            return;
+        }
+        NetworkAdaptersList::const_iterator netit;
+        for (netit = hardwareMachine.llNetworkAdapters.begin();
+             netit != hardwareMachine.llNetworkAdapters.end();
+             ++netit)
+        {
+            if (netit->mode == NetworkAttachmentType_NATNetwork)
+            {
+                m->sv = SettingsVersion_v1_14;
+                break;
+            }
+        }
+    }
+
+    if (m->sv < SettingsVersion_v1_14)
+    {
+        unsigned cOhciCtrls = 0;
+        unsigned cEhciCtrls = 0;
+        bool fNonStdName = false;
+
+        for (USBControllerList::const_iterator it = hardwareMachine.usbSettings.llUSBControllers.begin();
+             it != hardwareMachine.usbSettings.llUSBControllers.end();
+             ++it)
+        {
+            const USBController &ctrl = *it;
+
+            switch (ctrl.enmType)
+            {
+                case USBControllerType_OHCI:
+                    cOhciCtrls++;
+                    if (ctrl.strName != "OHCI")
+                        fNonStdName = true;
+                    break;
+                case USBControllerType_EHCI:
+                    cEhciCtrls++;
+                    if (ctrl.strName != "EHCI")
+                        fNonStdName = true;
+                    break;
+                default:
+                    /* Anything unknown forces a bump. */
+                    fNonStdName = true;
+            }
+
+            /* Skip checking other controllers if the settings bump is necessary. */
+            if (cOhciCtrls > 1 || cEhciCtrls > 1 || fNonStdName)
+            {
+                m->sv = SettingsVersion_v1_14;
+                break;
+            }
+        }
+    }
+
+    if (m->sv < SettingsVersion_v1_13)
+    {
+        // VirtualBox 4.2 adds tracing, autostart, UUID in directory and groups.
+        if (   !debugging.areDefaultSettings()
+            || !autostart.areDefaultSettings()
+            || machineUserData.fDirectoryIncludesUUID
+            || machineUserData.llGroups.size() > 1
+            || machineUserData.llGroups.front() != "/")
+            m->sv = SettingsVersion_v1_13;
+    }
+
+    if (m->sv < SettingsVersion_v1_13)
+    {
+        // VirtualBox 4.2 changes the units for bandwidth group limits.
+        for (BandwidthGroupList::const_iterator it = hardwareMachine.ioSettings.llBandwidthGroups.begin();
+             it != hardwareMachine.ioSettings.llBandwidthGroups.end();
+             ++it)
+        {
+            const BandwidthGroup &gr = *it;
+            if (gr.cMaxBytesPerSec % _1M)
+            {
+                // Bump version if a limit cannot be expressed in megabytes
+                m->sv = SettingsVersion_v1_13;
+                break;
+            }
+        }
+    }
+
+    if (m->sv < SettingsVersion_v1_12)
+    {
+        // VirtualBox 4.1 adds PCI passthrough and emulated USB Smart Card reader
+        if (   hardwareMachine.pciAttachments.size()
+            || hardwareMachine.fEmulatedUSBCardReader)
+            m->sv = SettingsVersion_v1_12;
+    }
+
+    if (m->sv < SettingsVersion_v1_12)
+    {
+        // VirtualBox 4.1 adds a promiscuous mode policy to the network
+        // adapters and a generic network driver transport.
+        NetworkAdaptersList::const_iterator netit;
+        for (netit = hardwareMachine.llNetworkAdapters.begin();
+             netit != hardwareMachine.llNetworkAdapters.end();
+             ++netit)
+        {
+            if (   netit->enmPromiscModePolicy != NetworkAdapterPromiscModePolicy_Deny
+                || netit->mode == NetworkAttachmentType_Generic
+                || !netit->areGenericDriverDefaultSettings()
+               )
+            {
+                m->sv = SettingsVersion_v1_12;
+                break;
+            }
+        }
+    }
+
+    if (m->sv < SettingsVersion_v1_11)
+    {
+        // VirtualBox 4.0 adds HD audio, CPU priorities, ~fault tolerance~,
+        // per-machine media registries, VRDE, JRockitVE, bandwidth groups,
+        // ICH9 chipset
+        if (    hardwareMachine.audioAdapter.controllerType == AudioControllerType_HDA
+             || hardwareMachine.ulCpuExecutionCap != 100
+             || mediaRegistry.llHardDisks.size()
+             || mediaRegistry.llDvdImages.size()
+             || mediaRegistry.llFloppyImages.size()
+             || !hardwareMachine.vrdeSettings.strVrdeExtPack.isEmpty()
+             || !hardwareMachine.vrdeSettings.strAuthLibrary.isEmpty()
+             || machineUserData.strOsType == "JRockitVE"
+             || hardwareMachine.ioSettings.llBandwidthGroups.size()
+             || hardwareMachine.chipsetType == ChipsetType_ICH9
+           )
+            m->sv = SettingsVersion_v1_11;
+    }
+
+    if (m->sv < SettingsVersion_v1_10)
+    {
+        /* If the properties contain elements other than "TCP/Ports" and "TCP/Address",
+         * then increase the version to at least VBox 3.2, which can have video channel properties.
+         */
+        unsigned cOldProperties = 0;
+
+        StringsMap::const_iterator it = hardwareMachine.vrdeSettings.mapProperties.find("TCP/Ports");
+        if (it != hardwareMachine.vrdeSettings.mapProperties.end())
+            cOldProperties++;
+        it = hardwareMachine.vrdeSettings.mapProperties.find("TCP/Address");
+        if (it != hardwareMachine.vrdeSettings.mapProperties.end())
+            cOldProperties++;
+
+        if (hardwareMachine.vrdeSettings.mapProperties.size() != cOldProperties)
+            m->sv = SettingsVersion_v1_10;
+    }
+
+    if (m->sv < SettingsVersion_v1_11)
+    {
+        /* If the properties contain elements other than "TCP/Ports", "TCP/Address",
+         * "VideoChannel/Enabled" and "VideoChannel/Quality" then increase the version to VBox 4.0.
+         */
+        unsigned cOldProperties = 0;
+
+        StringsMap::const_iterator it = hardwareMachine.vrdeSettings.mapProperties.find("TCP/Ports");
+        if (it != hardwareMachine.vrdeSettings.mapProperties.end())
+            cOldProperties++;
+        it = hardwareMachine.vrdeSettings.mapProperties.find("TCP/Address");
+        if (it != hardwareMachine.vrdeSettings.mapProperties.end())
+            cOldProperties++;
+        it = hardwareMachine.vrdeSettings.mapProperties.find("VideoChannel/Enabled");
+        if (it != hardwareMachine.vrdeSettings.mapProperties.end())
+            cOldProperties++;
+        it = hardwareMachine.vrdeSettings.mapProperties.find("VideoChannel/Quality");
+        if (it != hardwareMachine.vrdeSettings.mapProperties.end())
+            cOldProperties++;
+
+        if (hardwareMachine.vrdeSettings.mapProperties.size() != cOldProperties)
+            m->sv = SettingsVersion_v1_11;
+    }
+
+    // settings version 1.9 is required if there is not exactly one DVD
+    // or more than one floppy drive present or the DVD is not at the secondary
+    // master; this check is a bit more complicated
+    //
+    // settings version 1.10 is required if the host cache should be disabled
+    //
+    // settings version 1.11 is required for bandwidth limits and if more than
+    // one controller of each type is present.
+    if (m->sv < SettingsVersion_v1_11)
+    {
+        // count attached DVDs and floppies (only if < v1.9)
+        size_t cDVDs = 0;
+        size_t cFloppies = 0;
+
+        // count storage controllers (if < v1.11)
+        size_t cSata = 0;
+        size_t cScsiLsi = 0;
+        size_t cScsiBuslogic = 0;
+        size_t cSas = 0;
+        size_t cIde = 0;
+        size_t cFloppy = 0;
+
+        // need to run thru all the storage controllers and attached devices to figure this out
+        for (StorageControllersList::const_iterator it = hardwareMachine.storage.llStorageControllers.begin();
+             it != hardwareMachine.storage.llStorageControllers.end();
+             ++it)
+        {
+            const StorageController &sctl = *it;
+
+            // count storage controllers of each type; 1.11 is required if more than one
+            // controller of one type is present
+            switch (sctl.storageBus)
+            {
+                case StorageBus_IDE:
+                    cIde++;
+                    break;
+                case StorageBus_SATA:
+                    cSata++;
+                    break;
+                case StorageBus_SAS:
+                    cSas++;
+                    break;
+                case StorageBus_SCSI:
+                    if (sctl.controllerType == StorageControllerType_LsiLogic)
+                        cScsiLsi++;
+                    else
+                        cScsiBuslogic++;
+                    break;
+                case StorageBus_Floppy:
+                    cFloppy++;
+                    break;
+                default:
+                    // Do nothing
+                    break;
+            }
+
+            if (   cSata > 1
+                || cScsiLsi > 1
+                || cScsiBuslogic > 1
+                || cSas > 1
+                || cIde > 1
+                || cFloppy > 1)
+            {
+                m->sv = SettingsVersion_v1_11;
+                break; // abort the loop -- we will not raise the version further
+            }
+
+            for (AttachedDevicesList::const_iterator it2 = sctl.llAttachedDevices.begin();
+                 it2 != sctl.llAttachedDevices.end();
+                 ++it2)
+            {
+                const AttachedDevice &att = *it2;
+
+                // Bandwidth limitations are new in VirtualBox 4.0 (1.11)
+                if (m->sv < SettingsVersion_v1_11)
+                {
+                    if (att.strBwGroup.length() != 0)
+                    {
+                        m->sv = SettingsVersion_v1_11;
+                        break; // abort the loop -- we will not raise the version further
+                    }
+                }
+
+                // disabling the host IO cache requires settings version 1.10
+                if (    (m->sv < SettingsVersion_v1_10)
+                     && (!sctl.fUseHostIOCache)
+                   )
+                    m->sv = SettingsVersion_v1_10;
+
+                // we can only write the StorageController/@Instance attribute with v1.9
+                if (    (m->sv < SettingsVersion_v1_9)
+                     && (sctl.ulInstance != 0)
+                   )
+                    m->sv = SettingsVersion_v1_9;
+
+                if (m->sv < SettingsVersion_v1_9)
+                {
+                    if (att.deviceType == DeviceType_DVD)
+                    {
+                         if (    (sctl.storageBus != StorageBus_IDE) // DVD at bus other than DVD?
+                              || (att.lPort != 1)                    // DVDs not at secondary master?
+                              || (att.lDevice != 0)
+                            )
+                            m->sv = SettingsVersion_v1_9;
+
+                        ++cDVDs;
+                    }
+                    else if (att.deviceType == DeviceType_Floppy)
+                        ++cFloppies;
+                }
+            }
+
+            if (m->sv >= SettingsVersion_v1_11)
+                break;  // abort the loop -- we will not raise the version further
+        }
+
+        // VirtualBox before 3.1 had zero or one floppy and exactly one DVD,
+        // so any deviation from that will require settings version 1.9
+        if (    (m->sv < SettingsVersion_v1_9)
+             && (    (cDVDs != 1)
+                  || (cFloppies > 1)
+                )
+           )
+            m->sv = SettingsVersion_v1_9;
+    }
+
+    // VirtualBox 3.2: Check for non default I/O settings
+    if (m->sv < SettingsVersion_v1_10)
+    {
+        if (   (hardwareMachine.ioSettings.fIOCacheEnabled != true)
+            || (hardwareMachine.ioSettings.ulIOCacheSize != 5)
+                // and page fusion
+            || (hardwareMachine.fPageFusionEnabled)
+                // and CPU hotplug, RTC timezone control, HID type and HPET
+            || machineUserData.fRTCUseUTC
+            || hardwareMachine.fCpuHotPlug
+            || hardwareMachine.pointingHIDType != PointingHIDType_PS2Mouse
+            || hardwareMachine.keyboardHIDType != KeyboardHIDType_PS2Keyboard
+            || hardwareMachine.fHPETEnabled
+           )
+            m->sv = SettingsVersion_v1_10;
+    }
+
+    // VirtualBox 3.2 adds NAT and boot priority to the NIC config in Main
+    // VirtualBox 4.0 adds network bandwitdth
+    if (m->sv < SettingsVersion_v1_11)
+    {
+        NetworkAdaptersList::const_iterator netit;
+        for (netit = hardwareMachine.llNetworkAdapters.begin();
+             netit != hardwareMachine.llNetworkAdapters.end();
+             ++netit)
+        {
+            if (    (m->sv < SettingsVersion_v1_12)
+                 && (netit->strBandwidthGroup.isNotEmpty())
+               )
+            {
+                /* New in VirtualBox 4.1 */
+                m->sv = SettingsVersion_v1_12;
+                break;
+            }
+            else if (    (m->sv < SettingsVersion_v1_10)
+                      && (netit->fEnabled)
+                      && (netit->mode == NetworkAttachmentType_NAT)
+                      && (   netit->nat.u32Mtu != 0
+                          || netit->nat.u32SockRcv != 0
+                          || netit->nat.u32SockSnd != 0
+                          || netit->nat.u32TcpRcv != 0
+                          || netit->nat.u32TcpSnd != 0
+                          || !netit->nat.fDNSPassDomain
+                          || netit->nat.fDNSProxy
+                          || netit->nat.fDNSUseHostResolver
+                          || netit->nat.fAliasLog
+                          || netit->nat.fAliasProxyOnly
+                          || netit->nat.fAliasUseSamePorts
+                          || netit->nat.strTFTPPrefix.length()
+                          || netit->nat.strTFTPBootFile.length()
+                          || netit->nat.strTFTPNextServer.length()
+                          || netit->nat.mapRules.size()
+                         )
+                     )
+            {
+                m->sv = SettingsVersion_v1_10;
+                // no break because we still might need v1.11 above
+            }
+            else if (    (m->sv < SettingsVersion_v1_10)
+                      && (netit->fEnabled)
+                      && (netit->ulBootPriority != 0)
+                    )
+            {
+                m->sv = SettingsVersion_v1_10;
+                // no break because we still might need v1.11 above
+            }
+        }
+    }
+
+    // all the following require settings version 1.9
+    if (    (m->sv < SettingsVersion_v1_9)
+         && (    (hardwareMachine.firmwareType >= FirmwareType_EFI)
+              || machineUserData.fTeleporterEnabled
+              || machineUserData.uTeleporterPort
+              || !machineUserData.strTeleporterAddress.isEmpty()
+              || !machineUserData.strTeleporterPassword.isEmpty()
+              || (!hardwareMachine.uuid.isZero() && hardwareMachine.uuid.isValid())
+            )
+        )
+        m->sv = SettingsVersion_v1_9;
+
+    // "accelerate 2d video" requires settings version 1.8
+    if (    (m->sv < SettingsVersion_v1_8)
+         && (hardwareMachine.graphicsAdapter.fAccelerate2DVideo)
+       )
+        m->sv = SettingsVersion_v1_8;
+
+    // The hardware versions other than "1" requires settings version 1.4 (2.1+).
+    if (    m->sv < SettingsVersion_v1_4
+         && hardwareMachine.strVersion != "1"
+       )
+        m->sv = SettingsVersion_v1_4;
+}
+
+/**
+ * Called from Main code to write a machine config file to disk. This builds a DOM tree from
+ * the member variables and then writes the XML file; it throws xml::Error instances on errors,
+ * in particular if the file cannot be written.
+ */
+void MachineConfigFile::write(const com::Utf8Str &strFilename, PCVBOXCRYPTOIF pCryptoIf, const char *pszPassword)
+{
+    try
+    {
+        // createStubDocument() sets the settings version to at least 1.7; however,
+        // we might need to enfore a later settings version if incompatible settings
+        // are present:
+        bumpSettingsVersionIfNeeded();
+
+        m->strFilename = strFilename;
+        /*
+         * Only create a backup if it is not encrypted.
+         * Otherwise we get an unencrypted copy of the settings.
+         */
+        if (strKeyId.isEmpty() && strKeyStore.isEmpty())
+            specialBackupIfFirstBump();
+        createStubDocument();
+
+        if (strKeyStore.isNotEmpty())
+        {
+            xml::ElementNode *pelmMachine = m->pelmRoot->createChild("MachineEncrypted");
+            buildMachineEncryptedXML(*pelmMachine,
+                                       MachineConfigFile::BuildMachineXML_IncludeSnapshots
+                                     | MachineConfigFile::BuildMachineXML_MediaRegistry,
+                                         // but not BuildMachineXML_WriteVBoxVersionAttribute
+                                     NULL, /* pllElementsWithUuidAttributes */
+                                     pCryptoIf,
+                                     pszPassword);
+        }
+        else
+        {
+            xml::ElementNode *pelmMachine = m->pelmRoot->createChild("Machine");
+            buildMachineXML(*pelmMachine,
+                              MachineConfigFile::BuildMachineXML_IncludeSnapshots
+                            | MachineConfigFile::BuildMachineXML_MediaRegistry,
+                                // but not BuildMachineXML_WriteVBoxVersionAttribute
+                            NULL); /* pllElementsWithUuidAttributes */
+        }
+
+        // now go write the XML
+        xml::XmlFileWriter writer(*m->pDoc);
+        writer.write(m->strFilename.c_str(), true /*fSafe*/);
+
+        m->fFileExists = true;
+        clearDocument();
+        LogRel(("Finished saving settings file \"%s\"\n", m->strFilename.c_str()));
+    }
+    catch (...)
+    {
+        clearDocument();
+        LogRel(("Finished saving settings file \"%s\" with failure\n", m->strFilename.c_str()));
+        throw;
+    }
+}
diff --git a/src/VBox/Main/xml/VirtualBox-settings.xsd b/src/VBox/Main/xml/VirtualBox-settings.xsd
new file mode 100644
index 00000000..60f7303c
--- /dev/null
+++ b/src/VBox/Main/xml/VirtualBox-settings.xsd
@@ -0,0 +1,1514 @@
+<?xml version="1.0" encoding="UTF-8"?>
+<!--
+ *  :tabSize=2:indentSize=2:noTabs=true:
+ *  :folding=explicit:collapseFolds=1:
+ *
+ *  Oracle VM VirtualBox Settings Schema
+ *  Common definitions
+-->
+<!--
+    Copyright (C) 2004-2023 Oracle and/or its affiliates.
+
+    This file is part of VirtualBox base platform packages, as
+    available from https://www.virtualbox.org.
+
+    This program is free software; you can redistribute it and/or
+    modify it under the terms of the GNU General Public License
+    as published by the Free Software Foundation, in version 3 of the
+    License.
+
+    This program is distributed in the hope that it will be useful, but
+    WITHOUT ANY WARRANTY; without even the implied warranty of
+    MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
+    General Public License for more details.
+
+    You should have received a copy of the GNU General Public License
+    along with this program; if not, see <https://www.gnu.org/licenses>.
+
+    SPDX-License-Identifier: GPL-3.0-only
+-->
+
+<xsd:schema
+  xmlns:xsd="http://www.w3.org/2001/XMLSchema"
+  xmlns="http://www.virtualbox.org/"
+  xmlns:vb="http://www.virtualbox.org/"
+  targetNamespace="http://www.virtualbox.org/"
+  elementFormDefault="qualified"
+>
+
+<xsd:annotation>
+  <xsd:documentation xml:lang="en">
+    Oracle VM VirtualBox Settings Schema (common definitions).
+    Copyright (C) 2004-2023 Oracle and/or its affiliates.
+  </xsd:documentation>
+</xsd:annotation>
+
+<!--
+// Simple types
+/////////////////////////////////////////////////////////////////////////
+-->
+
+<xsd:simpleType name="TUUID">
+  <xsd:restriction base="xsd:token">
+    <xsd:pattern value="\{[0-9A-Fa-f]{8}-[0-9A-Fa-f]{4}-[0-9A-Fa-f]{4}-[0-9A-Fa-f]{4}-[0-9A-Fa-f]{12}\}"/>
+  </xsd:restriction>
+</xsd:simpleType>
+
+<xsd:simpleType name="TNonNullUUID">
+  <xsd:restriction base="TUUID">
+    <xsd:pattern value=".*[1-9A-Fa-f]+.*"/>
+  </xsd:restriction>
+</xsd:simpleType>
+
+<xsd:simpleType name="TUInt8">
+  <xsd:union>
+    <xsd:simpleType>
+      <xsd:restriction base="xsd:unsignedByte">
+      </xsd:restriction>
+    </xsd:simpleType>
+    <xsd:simpleType>
+      <xsd:restriction base="xsd:string">
+        <xsd:pattern value="0[xX][A-Fa-f0-9]{1,2}"/>
+      </xsd:restriction>
+    </xsd:simpleType>
+  </xsd:union>
+</xsd:simpleType>
+
+<xsd:simpleType name="TUInt16">
+  <xsd:union>
+    <xsd:simpleType>
+      <xsd:restriction base="xsd:unsignedShort">
+      </xsd:restriction>
+    </xsd:simpleType>
+    <xsd:simpleType>
+      <xsd:restriction base="xsd:string">
+        <xsd:pattern value="0[xX][A-Fa-f0-9]{1,4}"/>
+      </xsd:restriction>
+    </xsd:simpleType>
+  </xsd:union>
+</xsd:simpleType>
+
+<xsd:simpleType name="TUInt16Hex">
+  <xsd:restriction base="xsd:string">
+    <xsd:pattern value="0x[A-Fa-f0-9]{1,4}"/>
+  </xsd:restriction>
+</xsd:simpleType>
+
+<xsd:simpleType name="TUInt16HexNoBase">
+  <xsd:restriction base="xsd:string">
+    <xsd:pattern value="[A-Fa-f0-9]{1,4}"/>
+  </xsd:restriction>
+</xsd:simpleType>
+
+<xsd:simpleType name="TUInt32Hex">
+  <xsd:restriction base="xsd:string">
+    <xsd:pattern value="0x[A-Fa-f0-9]{1,8}"/>
+  </xsd:restriction>
+</xsd:simpleType>
+
+<xsd:simpleType name="TUInt64Hex">
+  <xsd:restriction base="xsd:string">
+    <xsd:pattern value="0x[A-Fa-f0-9]{1,16}"/>
+  </xsd:restriction>
+</xsd:simpleType>
+
+<xsd:simpleType name="TLocalFile">
+  <xsd:restriction base="xsd:string">
+    <xsd:pattern value=".+"/>
+  </xsd:restriction>
+</xsd:simpleType>
+
+<xsd:simpleType name="TDeviceType">
+  <xsd:restriction base="xsd:token">
+    <xsd:enumeration value="None"/>
+    <xsd:enumeration value="Floppy"/>
+    <xsd:enumeration value="DVD"/>
+    <xsd:enumeration value="HardDisk"/>
+    <xsd:enumeration value="Network"/>
+  </xsd:restriction>
+</xsd:simpleType>
+
+<xsd:simpleType name="TMediumDeviceType">
+  <xsd:restriction base="TDeviceType">
+    <xsd:enumeration value="Floppy"/>
+    <xsd:enumeration value="DVD"/>
+    <xsd:enumeration value="HardDisk"/>
+  </xsd:restriction>
+</xsd:simpleType>
+
+<xsd:simpleType name="TMediumType">
+  <xsd:restriction base="xsd:string">
+    <xsd:enumeration value="Normal"/>
+    <xsd:enumeration value="Immutable"/>
+    <xsd:enumeration value="Writethrough"/>
+    <xsd:enumeration value="Shareable"/>
+    <xsd:enumeration value="Readonly"/>
+    <xsd:enumeration value="MultiAttach"/>
+  </xsd:restriction>
+</xsd:simpleType>
+
+<xsd:simpleType name="TVMProcPriority">
+  <xsd:restriction base="xsd:string">
+    <xsd:enumeration value="Invalid"/>
+    <xsd:enumeration value="Default"/>
+    <xsd:enumeration value="Flat"/>
+    <xsd:enumeration value="Low"/>
+    <xsd:enumeration value="Normal"/>
+    <xsd:enumeration value="High"/>
+  </xsd:restriction>
+</xsd:simpleType>
+
+<xsd:simpleType name="TMonitorCount">
+  <xsd:restriction base="xsd:unsignedInt">
+    <xsd:minInclusive value="1"/>
+    <!-- This should be in sync with VBOX_VIDEO_MAX_SCREENS in VBoxVideo.h -->
+    <xsd:maxInclusive value="64"/>
+  </xsd:restriction>
+</xsd:simpleType>
+
+<xsd:simpleType name="TUSBDeviceFilterAction">
+  <xsd:restriction base="xsd:token">
+    <xsd:enumeration value="Ignore"/>
+    <xsd:enumeration value="Hold"/>
+  </xsd:restriction>
+</xsd:simpleType>
+
+<xsd:simpleType name="TNonEmptyString">
+  <xsd:restriction base="xsd:string">
+    <xsd:pattern value=".+"/>
+  </xsd:restriction>
+</xsd:simpleType>
+
+<xsd:simpleType name="TPresentDateTimeUTC">
+  <xsd:restriction base="xsd:dateTime">
+    <xsd:minInclusive value="1900-01-01T00:00:00Z"/>
+    <xsd:maxInclusive value="199999999-12-31T23:59:59Z"/>
+    <xsd:pattern value=".+-.+-.+T.+:.+:[0-9]{2}Z"/>
+  </xsd:restriction>
+</xsd:simpleType>
+
+
+<xsd:simpleType name="TAuthType">
+  <xsd:restriction base="xsd:string">
+    <xsd:enumeration value="null"/> <!-- deprecated -->
+    <xsd:enumeration value="Null"/>
+    <xsd:enumeration value="Guest"/>
+    <xsd:enumeration value="External"/>
+  </xsd:restriction>
+</xsd:simpleType>
+
+<xsd:simpleType name="TNetworkAdapterType">
+  <xsd:restriction base="xsd:string">
+    <xsd:enumeration value="Am79C970A"/>
+    <xsd:enumeration value="Am79C973"/>
+    <xsd:enumeration value="Am79C960"/>
+    <xsd:enumeration value="82540EM"/>
+    <xsd:enumeration value="82543GC"/>
+    <xsd:enumeration value="82545EM"/>
+    <xsd:enumeration value="virtio"/>
+  </xsd:restriction>
+</xsd:simpleType>
+
+<xsd:simpleType name="TTriStateBoolType">
+  <xsd:restriction base="xsd:string">
+    <xsd:enumeration value="false"/>
+    <xsd:enumeration value="true"/>
+    <xsd:enumeration value="default"/>
+  </xsd:restriction>
+</xsd:simpleType>
+
+<xsd:simpleType name="TBIOSBootMenuModeType">
+  <xsd:restriction base="xsd:string">
+    <xsd:enumeration value="Disabled"/>
+    <xsd:enumeration value="MenuOnly"/>
+    <xsd:enumeration value="MessageAndMenu"/>
+    <xsd:enumeration value="messageandmenu"/> <!-- deprecated -->
+  </xsd:restriction>
+</xsd:simpleType>
+
+<xsd:simpleType name="TLocalOrUTC">
+  <xsd:restriction base="xsd:token">
+    <xsd:enumeration value="local"/>
+    <xsd:enumeration value="UTC"/>
+  </xsd:restriction>
+</xsd:simpleType>
+
+<xsd:simpleType name="TClipboardMode">
+  <xsd:restriction base="xsd:string">
+    <xsd:enumeration value="Disabled"/>
+    <xsd:enumeration value="HostToGuest"/>
+    <xsd:enumeration value="GuestToHost"/>
+    <xsd:enumeration value="Bidirectional"/>
+  </xsd:restriction>
+</xsd:simpleType>
+
+<xsd:simpleType name="TDragAndDropMode">
+  <xsd:restriction base="xsd:string">
+    <xsd:enumeration value="Disabled"/>
+    <xsd:enumeration value="HostToGuest"/>
+    <xsd:enumeration value="GuestToHost"/>
+    <xsd:enumeration value="Bidirectional"/>
+  </xsd:restriction>
+</xsd:simpleType>
+
+<xsd:simpleType name="TBandwidthGroupType">
+  <xsd:restriction base="xsd:string">
+    <xsd:enumeration value="Disk"/>
+    <xsd:enumeration value="Network"/>
+  </xsd:restriction>
+</xsd:simpleType>
+
+<xsd:simpleType name="TPortMode">
+  <xsd:restriction base="xsd:string">
+    <xsd:enumeration value="Disconnected"/>
+    <xsd:enumeration value="RawFile"/>
+    <xsd:enumeration value="HostPipe"/>
+    <xsd:enumeration value="HostDevice"/>
+    <xsd:enumeration value="TCP"/>
+  </xsd:restriction>
+</xsd:simpleType>
+
+<xsd:simpleType name="TStorageControllerType">
+  <xsd:restriction base="xsd:token">
+    <xsd:enumeration value="AHCI"/>
+    <xsd:enumeration value="LsiLogic"/>
+    <xsd:enumeration value="BusLogic"/>
+    <xsd:enumeration value="PIIX3"/>
+    <xsd:enumeration value="PIIX4"/>
+    <xsd:enumeration value="ICH6"/>
+    <xsd:enumeration value="LsiLogicSas"/>
+    <xsd:enumeration value="I82078"/>
+    <xsd:enumeration value="USB"/>
+    <xsd:enumeration value="NVMe"/>
+    <xsd:enumeration value="VirtioSCSI"/>
+  </xsd:restriction>
+</xsd:simpleType>
+
+<xsd:simpleType name="TDisplayControllerType">
+  <xsd:restriction base="xsd:token">
+    <xsd:enumeration value="VBoxVGA"/>
+    <xsd:enumeration value="VMSVGA"/>
+    <xsd:enumeration value="VBoxSVGA"/>
+  </xsd:restriction>
+</xsd:simpleType>
+
+<!--
+// Complex types
+/////////////////////////////////////////////////////////////////////////
+-->
+<xsd:complexType name="TDHCPServer">
+  <xsd:sequence>
+    <xsd:element name="Options" minOccurs="0">
+      <xsd:complexType>
+        <xsd:sequence>
+          <xsd:element name="Option" type="TDHCPOption" minOccurs="0" maxOccurs="unbounded"/>
+        </xsd:sequence>
+      </xsd:complexType>
+    </xsd:element>
+  </xsd:sequence>
+  <xsd:attribute name="networkName" type="xsd:string"  use="required"/>
+  <xsd:attribute name="lowerIP"     type="xsd:string"  use="required"/>
+  <xsd:attribute name="upperIP"     type="xsd:string"  use="required"/>
+  <xsd:attribute name="IPAddress"   type="xsd:string"  use="required"/>
+  <xsd:attribute name="networkMask" type="xsd:string"  use="required"/>
+  <xsd:attribute name="enabled"     type="xsd:boolean" use="required"/>
+</xsd:complexType>
+
+<xsd:complexType name="TDHCPOption">
+  <xsd:attribute name="name" type="xsd:string" use="required"/>
+  <xsd:attribute name="value" type="xsd:string" use="required"/>
+  <xsd:attribute name="encoding" type="xsd:integer" default="0"/>
+</xsd:complexType>
+
+<xsd:complexType name="TNATNetwork">
+  <xsd:sequence>
+    <xsd:element name="PortForwarding4" minOccurs="0">
+      <xsd:complexType>
+        <xsd:sequence>
+          <xsd:element name="Forwarding" type="TNATPortForwarding" minOccurs="0" maxOccurs="unbounded"/>
+        </xsd:sequence>
+      </xsd:complexType>
+    </xsd:element>
+    <xsd:element name="PortForwarding6" minOccurs="0">
+      <xsd:complexType>
+        <xsd:sequence>
+          <xsd:element name="Forwarding" type="TNATPortForwarding" minOccurs="0" maxOccurs="unbounded"/>
+        </xsd:sequence>
+      </xsd:complexType>
+    </xsd:element>
+    <xsd:element name="Mappings" minOccurs="0">
+      <xsd:complexType>
+        <xsd:sequence>
+          <xsd:element name="Loopback4" type="TNATLoopback4" minOccurs="0" maxOccurs="unbounded"/>
+        </xsd:sequence>
+      </xsd:complexType>
+    </xsd:element>
+  </xsd:sequence>
+  <xsd:attribute name="networkName" type="xsd:string"  use="required"/>
+  <xsd:attribute name="enabled"     type="xsd:boolean" use="required"/>
+  <xsd:attribute name="network"     type="xsd:string"  use="required"/>
+  <xsd:attribute name="ipv6"        type="xsd:boolean" use="required"/>
+  <xsd:attribute name="ipv6prefix"  type="xsd:string"  use="required"/>
+  <xsd:attribute name="advertiseDefaultIPv6Route" type="xsd:boolean" use="required"/>
+  <xsd:attribute name="needDhcp"    type="xsd:boolean" use="required"/>
+  <xsd:attribute name="loopback6"   type="xsd:integer" default="0"/>
+</xsd:complexType>
+
+<xsd:complexType name="TNATLoopback4">
+  <xsd:attribute name="address" type="xsd:string" use="required"/>
+  <xsd:attribute name="offset" type="xsd:integer" use="required"/>
+</xsd:complexType>
+
+<xsd:complexType name="TNATPortForwarding">
+  <xsd:attribute name="name" type="xsd:string" use="required"/>
+  <xsd:attribute name="proto" type="xsd:integer" use="required"/>
+  <xsd:attribute name="hostip" type="xsd:string" default=""/>
+  <xsd:attribute name="hostport" type="xsd:integer" use="required"/>
+  <xsd:attribute name="guestip" type="xsd:string" use="required"/>
+  <xsd:attribute name="guestport" type="xsd:integer" use="required"/>
+</xsd:complexType>
+
+<xsd:complexType name="TProperty">
+  <xsd:attribute name="name" type="xsd:token" use="required"/>
+  <xsd:attribute name="value" type="xsd:string" use="required"/>
+</xsd:complexType>
+
+<xsd:complexType name="THardDiskBase">
+  <xsd:sequence>
+    <xsd:element name="Description" type="xsd:string" minOccurs="0"/>
+    <xsd:element name="Property" type="TProperty" minOccurs="0" maxOccurs="unbounded"/>
+    <xsd:element name="HardDisk" type="TDiffHardDisk" minOccurs="0" maxOccurs="unbounded"/>
+  </xsd:sequence>
+  <xsd:attribute name="uuid" type="TNonNullUUID" use="required"/>
+  <xsd:attribute name="location" type="TLocalFile" use="required"/>
+  <xsd:attribute name="format" type="TNonEmptyString" use="required"/>
+</xsd:complexType>
+
+<xsd:complexType name="TDiffHardDisk">
+  <xsd:complexContent>
+    <xsd:extension base="THardDiskBase">
+      <xsd:attribute name="autoReset" type="xsd:boolean" default="false"/>
+    </xsd:extension>
+  </xsd:complexContent>
+</xsd:complexType>
+
+<xsd:complexType name="THardDisk">
+  <xsd:complexContent>
+    <xsd:extension base="THardDiskBase">
+      <xsd:attribute name="type" type="TMediumType" use="required"/>
+    </xsd:extension>
+  </xsd:complexContent>
+</xsd:complexType>
+
+<xsd:complexType name="TImage2">
+  <xsd:sequence>
+    <xsd:element name="Description" type="xsd:string" minOccurs="0"/>
+  </xsd:sequence>
+  <xsd:attribute name="uuid" type="TNonNullUUID" use="required"/>
+  <xsd:attribute name="location" type="TLocalFile" use="required"/>
+  <xsd:attribute name="type" type="TMediumType"/>
+</xsd:complexType>
+
+<xsd:complexType name="TImageRef">
+  <xsd:attribute name="uuid" type="TNonNullUUID" use="required"/>
+</xsd:complexType>
+
+<xsd:complexType name="THostDrive">
+  <xsd:attribute name="src" type="TLocalFile" use="required"/>
+</xsd:complexType>
+
+<xsd:complexType name="TUSBDeviceFilter">
+  <xsd:attribute name="name" type="TNonEmptyString" use="required"/>
+  <xsd:attribute name="active" type="xsd:boolean" use="required"/>
+  <xsd:attribute name="vendorId" type="xsd:token"/>
+  <xsd:attribute name="productId" type="xsd:token"/>
+  <xsd:attribute name="revision" type="xsd:token"/>
+  <xsd:attribute name="manufacturer" type="xsd:token"/>
+  <xsd:attribute name="product" type="xsd:token"/>
+  <xsd:attribute name="serialNumber" type="xsd:token"/>
+  <xsd:attribute name="port" type="xsd:token"/>
+  <xsd:attribute name="remote" type="xsd:token"/>
+  <xsd:attribute name="maskedInterfaces" type="xsd:unsignedInt" default="0"/>
+</xsd:complexType>
+
+<xsd:complexType name="TUSBDeviceFilters">
+  <xsd:sequence>
+    <xsd:element name="DeviceFilter" type="TUSBDeviceFilter" minOccurs="0"/>
+  </xsd:sequence>
+</xsd:complexType>
+
+<xsd:complexType name="THostUSBDeviceFilter">
+  <xsd:complexContent>
+    <xsd:extension base="TUSBDeviceFilter">
+      <xsd:attribute name="action" type="TUSBDeviceFilterAction" use="required"/>
+    </xsd:extension>
+  </xsd:complexContent>
+</xsd:complexType>
+
+<xsd:complexType name="TSystemProperties">
+  <xsd:attribute name="defaultMachineFolder" type="TLocalFile"/>
+  <xsd:attribute name="defaultHardDiskFolder" type="TLocalFile"/>
+  <xsd:attribute name="defaultHardDiskFormat" type="TNonEmptyString"/>
+  <xsd:attribute name="VRDEAuthLibrary" type="TLocalFile"/>
+  <xsd:attribute name="webServiceAuthLibrary" type="TLocalFile"/>
+  <xsd:attribute name="defaultVRDELibrary" type="TLocalFile"/>
+  <xsd:attribute name="HWVirtExEnabled" type="xsd:boolean"/>
+  <xsd:attribute name="LogHistoryCount" type="xsd:unsignedInt" default="3"/>
+  <xsd:attribute name="defaultVRDEExtPack" type="xsd:string"/>
+  <xsd:attribute name="exclusiveHwVirt" type="xsd:boolean"/>
+  <xsd:attribute name="proxyMode" type="xsd:string"/>
+</xsd:complexType>
+
+<xsd:complexType name="TExtraData">
+  <xsd:sequence>
+    <xsd:element name="ExtraDataItem" minOccurs="0" maxOccurs="unbounded">
+      <xsd:complexType>
+        <xsd:attribute name="name" type="xsd:token" use="required"/>
+        <xsd:attribute name="value" type="xsd:string" use="required"/>
+      </xsd:complexType>
+    </xsd:element>
+  </xsd:sequence>
+</xsd:complexType>
+
+<xsd:complexType name="TMediaRegistry">
+  <xsd:all>
+    <xsd:element name="HardDisks" minOccurs="0">
+      <xsd:complexType>
+        <xsd:sequence>
+          <xsd:element name="HardDisk" type="THardDisk" minOccurs="0" maxOccurs="unbounded"/>
+        </xsd:sequence>
+      </xsd:complexType>
+    </xsd:element>
+    <xsd:element name="DVDImages" minOccurs="0">
+      <xsd:complexType>
+        <xsd:sequence>
+          <xsd:element name="Image" type="TImage2" minOccurs="0" maxOccurs="unbounded"/>
+        </xsd:sequence>
+      </xsd:complexType>
+    </xsd:element>
+    <xsd:element name="FloppyImages" minOccurs="0">
+      <xsd:complexType>
+        <xsd:sequence>
+          <xsd:element name="Image" type="TImage2" minOccurs="0" maxOccurs="unbounded"/>
+        </xsd:sequence>
+      </xsd:complexType>
+    </xsd:element>
+  </xsd:all>
+</xsd:complexType>
+
+<xsd:complexType name="TGlobal">
+  <xsd:all>
+    <xsd:element name="MachineRegistry">
+      <xsd:complexType>
+        <xsd:sequence>
+          <xsd:element name="MachineEntry" minOccurs="0" maxOccurs="unbounded">
+            <xsd:complexType>
+              <xsd:attribute name="src" type="TLocalFile" use="required"/>
+              <xsd:attribute name="uuid" type="TNonNullUUID" use="required"/>
+            </xsd:complexType>
+          </xsd:element>
+        </xsd:sequence>
+      </xsd:complexType>
+    </xsd:element>
+    <xsd:element name="MediaRegistry" type="TMediaRegistry" minOccurs="0"/>
+    <xsd:element name="NetserviceRegistry" minOccurs="0">
+      <xsd:complexType>
+        <xsd:all>
+          <xsd:element name="DHCPServers" minOccurs="0">
+            <xsd:complexType>
+              <xsd:sequence>
+                <xsd:element name="DHCPServer" type="TDHCPServer" minOccurs="0" maxOccurs="unbounded"/>
+              </xsd:sequence>
+            </xsd:complexType>
+          </xsd:element>
+          <xsd:element name="NATNetworks" minOccurs="0">
+            <xsd:complexType>
+              <xsd:sequence>
+                <xsd:element name="NATNetwork" type="TNATNetwork" minOccurs="0" maxOccurs="unbounded"/>
+              </xsd:sequence>
+            </xsd:complexType>
+          </xsd:element>
+        </xsd:all>
+      </xsd:complexType>
+    </xsd:element>
+    <xsd:element name="USBDeviceFilters">
+      <xsd:complexType>
+        <xsd:sequence>
+          <xsd:element name="DeviceFilter" type="THostUSBDeviceFilter"
+                       minOccurs="0" maxOccurs="unbounded"/>
+        </xsd:sequence>
+      </xsd:complexType>
+    </xsd:element>
+    <xsd:element name="SystemProperties" type="TSystemProperties"/>
+    <xsd:element name="ExtraData" type="TExtraData" minOccurs="0"/>
+  </xsd:all>
+</xsd:complexType>
+
+<xsd:complexType name="THWVirtExType">
+  <xsd:attribute name="enabled" type="TTriStateBoolType"/>
+  <xsd:attribute name="exclusive" type="xsd:boolean"/>
+</xsd:complexType>
+
+<xsd:complexType name="THWVirtExNestedPagingType">
+  <xsd:attribute name="enabled" type="xsd:boolean"/>
+</xsd:complexType>
+
+<xsd:complexType name="THWVirtExVPIDType">
+  <xsd:attribute name="enabled" type="xsd:boolean"/>
+</xsd:complexType>
+
+<xsd:complexType name="THWVirtExUXType">
+  <xsd:attribute name="enabled" type="xsd:boolean"/>
+</xsd:complexType>
+
+<xsd:complexType name="TSyntheticCpuType">
+  <xsd:attribute name="enabled" type="xsd:boolean"/>
+</xsd:complexType>
+
+<xsd:complexType name="TPAEType">
+  <xsd:attribute name="enabled" type="xsd:boolean"/>
+</xsd:complexType>
+
+<xsd:complexType name="TLongModeType">
+  <xsd:attribute name="enabled" type="xsd:boolean"/>
+</xsd:complexType>
+
+<xsd:complexType name="THardwareVirtExLargePages">
+  <xsd:attribute name="enabled" type="xsd:boolean"/>
+</xsd:complexType>
+
+<xsd:complexType name="THardwareVirtForce">
+  <xsd:attribute name="enabled" type="xsd:boolean"/>
+</xsd:complexType>
+
+<xsd:simpleType name="TCPUCount">
+  <xsd:restriction base="xsd:unsignedInt">
+    <xsd:minInclusive value="1"/>
+    <xsd:maxInclusive value="64"/>
+  </xsd:restriction>
+</xsd:simpleType>
+
+<xsd:complexType name="TCpuIdLeaf">
+  <xsd:attribute name="id"        type="xsd:unsignedInt"       use="required"/>
+  <xsd:attribute name="eax"       type="xsd:unsignedInt"       use="required"/>
+  <xsd:attribute name="ebx"       type="xsd:unsignedInt"       use="required"/>
+  <xsd:attribute name="ecx"       type="xsd:unsignedInt"       use="required"/>
+  <xsd:attribute name="edx"       type="xsd:unsignedInt"       use="required"/>
+</xsd:complexType>
+
+<xsd:complexType name="TCpuIdTree">
+  <xsd:sequence>
+    <xsd:element name="CpuIdLeaf" type="TCpuIdLeaf"
+                 minOccurs="0" maxOccurs="unbounded"/>
+  </xsd:sequence>
+</xsd:complexType>
+
+<xsd:complexType name="TCPU">
+  <xsd:sequence>
+    <xsd:element name="HardwareVirtEx" type="THWVirtExType" minOccurs="0"/>
+    <xsd:element name="HardwareVirtExNestedPaging" type="THWVirtExNestedPagingType" minOccurs="0"/>
+    <xsd:element name="HardwareVirtExVPID" type="THWVirtExVPIDType" minOccurs="0"/>
+    <xsd:element name="HardwareVirtExUX" type="THWVirtExUXType" minOccurs="0"/>
+    <xsd:element name="PAE" type="TPAEType" minOccurs="0"/>
+    <xsd:element name="LongMode" type="TLongModeType" minOccurs="0"/>
+    <xsd:element name="HardwareVirtExLargePages" type="THardwareVirtExLargePages" minOccurs="0"/>
+    <xsd:element name="HardwareVirtForce" type="THardwareVirtForce" minOccurs="0"/>
+    <xsd:element name="SyntheticCpu" type="TSyntheticCpuType" minOccurs="0"/>
+    <xsd:element name="CpuIdTree" type="TCpuIdTree" minOccurs="0">
+      <xsd:unique name="TCPU-CpuIdTree-CpuIdLeaf">
+        <xsd:selector xpath="vb:CpuIdLeaf"/>
+        <xsd:field xpath="@id"/>
+      </xsd:unique>
+    </xsd:element>
+  </xsd:sequence>
+  <xsd:attribute name="count" type="TCPUCount" default="1"/>
+  <xsd:attribute name="hotplug" type="xsd:boolean" default="false"/>
+</xsd:complexType>
+
+<xsd:complexType name="TBoot">
+  <xsd:sequence>
+    <xsd:element name="Order" minOccurs="0" maxOccurs="unbounded">
+      <xsd:complexType>
+        <xsd:attribute name="position" use="required">
+          <xsd:simpleType>
+            <xsd:restriction base="xsd:unsignedInt">
+              <xsd:minInclusive value="1"/>
+              <xsd:maxInclusive value="4"/>
+            </xsd:restriction>
+          </xsd:simpleType>
+        </xsd:attribute>
+        <xsd:attribute name="device" type="TDeviceType" use="required"/>
+      </xsd:complexType>
+    </xsd:element>
+  </xsd:sequence>
+</xsd:complexType>
+
+<xsd:complexType name="TDisplay">
+  <xsd:attribute name="VRAMSize" default="8">
+    <xsd:simpleType>
+      <xsd:restriction base="xsd:unsignedInt">
+        <xsd:minInclusive value="0"/>
+        <xsd:maxInclusive value="256"/>
+      </xsd:restriction>
+    </xsd:simpleType>
+  </xsd:attribute>
+  <xsd:attribute name="monitorCount" type="TMonitorCount" default="1"/>
+  <xsd:attribute name="MonitorCount" type="TMonitorCount"/> <!-- deprecated -->
+  <xsd:attribute name="accelerate3D" type="xsd:boolean" default="false"/>
+  <xsd:attribute name="accelerate2DVideo" type="xsd:boolean" default="false"/>
+  <xsd:attribute name="controller" type="TDisplayControllerType" default="VBoxSVGA"/>
+</xsd:complexType>
+
+<xsd:complexType name="TVideoRecording">
+  <xsd:attribute name="enabled" type="xsd:boolean" default="false"/>
+  <xsd:attribute name="file" type="xsd:string"/>
+  <xsd:attribute name="horzRes">
+    <xsd:simpleType>
+      <xsd:restriction base="xsd:unsignedInt">
+        <xsd:minInclusive value="4"/>
+        <xsd:maxInclusive value="2097152"/>
+       </xsd:restriction>
+     </xsd:simpleType>
+  </xsd:attribute>
+  <xsd:attribute name="vertRes" type="xsd:unsignedInt"/>
+</xsd:complexType>
+
+<xsd:complexType name="TVideoCapture">
+  <xsd:attribute name="enabled" type="xsd:boolean" default="false"/>
+  <xsd:attribute name="file" type="xsd:string"/>
+  <xsd:attribute name="screens" type="xsd:unsignedLong"/> <!-- todo: fix writing of settings (writes -1) -->
+  <xsd:attribute name="horzRes">
+    <xsd:simpleType>
+      <xsd:restriction base="xsd:unsignedInt">
+        <xsd:minInclusive value="4"/>
+        <xsd:maxInclusive value="2097152"/>
+       </xsd:restriction>
+     </xsd:simpleType>
+  </xsd:attribute>
+  <xsd:attribute name="vertRes" type="xsd:unsignedInt"/>
+  <xsd:attribute name="rate" type="xsd:unsignedInt"/>
+  <xsd:attribute name="fps" type="xsd:unsignedInt"/>
+  <xsd:attribute name="maxTime" type="xsd:unsignedInt"/>
+  <xsd:attribute name="maxSize" type="xsd:unsignedInt"/>
+  <xsd:attribute name="options" type="xsd:string"/>
+</xsd:complexType>
+
+<xsd:complexType name="TVRDEProperties">
+  <xsd:sequence>
+    <xsd:element name="Property" type="TProperty" minOccurs="0" maxOccurs="unbounded"/>
+  </xsd:sequence>
+</xsd:complexType>
+
+<xsd:complexType name="TVideoChannel">
+  <xsd:attribute name="enabled" type="xsd:boolean" default="false"/>
+  <xsd:attribute name="quality" type="xsd:unsignedByte" default="75"/>
+</xsd:complexType>
+
+<xsd:complexType name="TRemoteDisplay">
+  <xsd:sequence>
+    <xsd:element name="VideoChannel" type="TVideoChannel" minOccurs="0"/> <!-- deprecated -->
+    <xsd:choice minOccurs="0">
+      <xsd:element name="VRDEProperties" type="TVRDEProperties"/>
+    </xsd:choice>
+  </xsd:sequence>
+  <xsd:attribute name="enabled" type="xsd:boolean" default="false"/>
+  <xsd:attribute name="port" type="xsd:string" default="3389"/> <!-- deprecated -->
+  <xsd:attribute name="authType" type="TAuthType" default="Null"/>
+  <xsd:attribute name="authTimeout" type="xsd:unsignedInt" default="5000"/>
+  <xsd:attribute name="allowMultiConnection" type="xsd:boolean" default="false"/>
+  <xsd:attribute name="reuseSingleConnection" type="xsd:boolean" default="false"/>
+</xsd:complexType>
+
+<xsd:complexType name="TBIOS">
+  <xsd:all>
+    <xsd:element name="ACPI" minOccurs="0">
+      <xsd:complexType>
+        <xsd:attribute name="enabled" type="xsd:boolean" use="required"/>
+      </xsd:complexType>
+    </xsd:element>
+    <xsd:element name="IOAPIC" minOccurs="0">
+      <xsd:complexType>
+          <xsd:attribute name="enabled" type="xsd:boolean" default="false"/>
+      </xsd:complexType>
+    </xsd:element>
+    <xsd:element name="Logo" minOccurs="0">
+      <xsd:complexType>
+        <xsd:attribute name="fadeIn" type="xsd:boolean" default="true"/>
+        <xsd:attribute name="fadeOut" type="xsd:boolean" default="true"/>
+        <xsd:attribute name="displayTime" type="xsd:unsignedInt" default="0"/>
+        <xsd:attribute name="imagePath" type="TLocalFile"/>
+      </xsd:complexType>
+    </xsd:element>
+    <xsd:element name="BootMenu" minOccurs="0">
+      <xsd:complexType>
+        <xsd:attribute name="mode" type="TBIOSBootMenuModeType" default="MessageAndMenu"/>
+      </xsd:complexType>
+    </xsd:element>
+    <xsd:element name="TimeOffset" minOccurs="0">
+      <xsd:complexType>
+        <xsd:attribute name="value" type="xsd:integer" default="0"/>
+      </xsd:complexType>
+    </xsd:element>
+    <xsd:element name="PXEDebug" minOccurs="0">
+      <xsd:complexType>
+        <xsd:attribute name="enabled" type="xsd:boolean" default="false"/>
+      </xsd:complexType>
+    </xsd:element>
+    <xsd:element name="NVRAM" minOccurs="0">
+      <xsd:complexType>
+        <xsd:attribute name="enabled" type="xsd:boolean" default="false"/>
+        <xsd:attribute name="path" type="xsd:string"/>
+      </xsd:complexType>
+    </xsd:element>
+    <xsd:element name="SmbiosUuidLittleEndian" minOccurs="0">
+      <xsd:complexType>
+          <xsd:attribute name="enabled" type="xsd:boolean" default="false"/>
+      </xsd:complexType>
+    </xsd:element>
+    <xsd:element name="IDEController" minOccurs="0"> <!-- deprecated -->
+      <xsd:complexType>
+        <xsd:attribute name="type">
+          <xsd:simpleType>
+            <xsd:restriction base="xsd:token">
+            <xsd:enumeration value="PIIX3"/>
+            <xsd:enumeration value="PIIX4"/>
+            <xsd:enumeration value="ICH6"/>
+            </xsd:restriction>
+          </xsd:simpleType>
+        </xsd:attribute>
+      </xsd:complexType>
+    </xsd:element>
+  </xsd:all>
+</xsd:complexType>
+
+<xsd:complexType name="TStorageControllerDevice">
+  <xsd:choice minOccurs="0">
+    <xsd:element name="Image" type="TImageRef"/>
+    <xsd:element name="HostDrive" type="THostDrive"/>
+  </xsd:choice>
+  <xsd:attribute name="type" type="TMediumDeviceType"/>
+  <xsd:attribute name="port" type="xsd:unsignedInt" default="0"/>
+  <xsd:attribute name="device" type="xsd:unsignedInt" default="0"/>
+  <xsd:attribute name="passthrough" type="xsd:boolean" default="false"/>
+  <xsd:attribute name="tempeject" type="xsd:boolean" default="false"/>
+  <xsd:attribute name="nonrotational" type="xsd:boolean" default="false"/>
+  <xsd:attribute name="discard" type="xsd:boolean" default="false"/>
+  <xsd:attribute name="hotpluggable" type="xsd:boolean" default="false"/>
+</xsd:complexType>
+
+<xsd:complexType name="TStorageController">
+  <xsd:sequence>
+    <xsd:element name="AttachedDevice" type="TStorageControllerDevice"
+                 minOccurs="0" maxOccurs="unbounded"/>
+  </xsd:sequence>
+  <xsd:attribute name="name" type="xsd:string" use="required"/>
+  <xsd:attribute name="type" type="TStorageControllerType" use="required"/>
+  <xsd:attribute name="PortCount"   type="xsd:unsignedInt" use="required"/>
+  <xsd:attribute name="useHostIOCache" type="xsd:boolean"  use="optional" default="true"/>
+  <xsd:attribute name="Bootable"    type="xsd:boolean"     use="optional"/>
+  <xsd:attribute name="PCIBus"      type="xsd:unsignedInt" use="optional"/>
+  <xsd:attribute name="PCIDevice"   type="xsd:unsignedInt" use="optional"/>
+  <xsd:attribute name="PCIFunction" type="xsd:unsignedInt" use="optional"/>
+  <xsd:attribute name="IDE0MasterEmulationPort" type="xsd:unsignedInt" use="optional"/>
+  <xsd:attribute name="IDE0SlaveEmulationPort"  type="xsd:unsignedInt" use="optional"/>
+  <xsd:attribute name="IDE1MasterEmulationPort" type="xsd:unsignedInt" use="optional"/>
+  <xsd:attribute name="IDE1SlaveEmulationPort"  type="xsd:unsignedInt" use="optional"/>
+</xsd:complexType>
+
+<xsd:complexType name="TSATAController"> <!-- deprecated -->
+  <xsd:sequence>
+    <xsd:element name="AttachedDevice" type="TStorageControllerDevice"
+                 minOccurs="0" maxOccurs="unbounded"/>
+  </xsd:sequence>
+  <xsd:attribute name="enabled"     type="xsd:boolean"     default="false"/>
+  <xsd:attribute name="PortCount"   type="xsd:unsignedInt" use="required"/>
+  <xsd:attribute name="IDE0MasterEmulationPort" type="xsd:unsignedInt" use="optional"/>
+  <xsd:attribute name="IDE0SlaveEmulationPort"  type="xsd:unsignedInt" use="optional"/>
+  <xsd:attribute name="IDE1MasterEmulationPort" type="xsd:unsignedInt" use="optional"/>
+  <xsd:attribute name="IDE1SlaveEmulationPort"  type="xsd:unsignedInt" use="optional"/>
+</xsd:complexType>
+
+<xsd:complexType name="TStorageControllers">
+  <xsd:sequence>
+    <xsd:element name="StorageController" type="TStorageController"
+                 minOccurs="0" maxOccurs="unbounded"/>
+  </xsd:sequence>
+</xsd:complexType>
+
+<xsd:complexType name="THardDiskAttachment">
+  <xsd:attribute name="hardDisk" type="TNonNullUUID"/>
+  <xsd:attribute name="bus" default="IDE">
+    <xsd:simpleType>
+      <xsd:restriction base="xsd:token">
+        <xsd:enumeration value="IDE"/>
+        <xsd:enumeration value="SATA"/>
+      </xsd:restriction>
+    </xsd:simpleType>
+  </xsd:attribute>
+  <xsd:attribute name="channel" type="xsd:unsignedInt" default="0"/>
+  <xsd:attribute name="device" type="xsd:unsignedInt" default="0"/>
+</xsd:complexType>
+
+<xsd:complexType name="THardDiskAttachments"> <!-- deprecated -->
+  <xsd:sequence>
+    <xsd:element name="HardDiskAttachment" type="THardDiskAttachment"
+                 minOccurs="0" maxOccurs="unbounded"/>
+  </xsd:sequence>
+</xsd:complexType>
+
+<xsd:complexType name="TDVDDrive">
+  <xsd:choice minOccurs="0">
+    <xsd:element name="Image" type="TImageRef"/>
+    <xsd:element name="HostDrive" type="THostDrive"/>
+  </xsd:choice>
+  <xsd:attribute name="passthrough" type="xsd:boolean" default="false"/>
+</xsd:complexType>
+
+<xsd:complexType name="TFloppyDrive">
+  <xsd:choice minOccurs="0">
+    <xsd:element name="Image" type="TImageRef"/>
+    <xsd:element name="HostDrive" type="THostDrive"/>
+  </xsd:choice>
+  <xsd:attribute name="enabled" type="xsd:boolean" default="true"/>
+</xsd:complexType>
+
+<xsd:complexType name="TUSBController">
+  <xsd:sequence>
+    <xsd:element name="DeviceFilter" type="TUSBDeviceFilter"
+                 minOccurs="0" maxOccurs="unbounded"/>
+  </xsd:sequence>
+  <xsd:attribute name="enabled" type="xsd:boolean" use="required"/>
+  <xsd:attribute name="enabledEhci" type="xsd:boolean" default="false"/>
+</xsd:complexType>
+
+<xsd:complexType name="TUSBController2">
+  <xsd:attribute name="name" type="xsd:string" use="required"/>
+  <xsd:attribute name="type" use="required">
+    <xsd:simpleType>
+      <xsd:restriction base="xsd:token">
+      <xsd:enumeration value="OHCI"/>
+      <xsd:enumeration value="EHCI"/>
+      <xsd:enumeration value="XHCI"/>
+      </xsd:restriction>
+    </xsd:simpleType>
+  </xsd:attribute>
+</xsd:complexType>
+
+<xsd:complexType name="TUSBControllers">
+  <xsd:sequence>
+    <xsd:element name="Controller" type="TUSBController2"
+                 minOccurs="0" maxOccurs="unbounded"/>
+  </xsd:sequence>
+</xsd:complexType>
+
+<xsd:complexType name="TUSB">
+  <xsd:sequence>
+    <xsd:element name="Controllers" type="TUSBControllers" minOccurs="0"/>
+    <xsd:element name="DeviceFilters" type="TUSBDeviceFilters" minOccurs="0"/>
+  </xsd:sequence>
+</xsd:complexType>
+
+
+<xsd:complexType name="TAudioAdapter">
+  <xsd:attribute name="enabled" type="xsd:boolean" default="false"/>
+  <xsd:attribute name="enabledIn" type="xsd:boolean" default="false"/>
+  <xsd:attribute name="enabledOut" type="xsd:boolean" default="false"/>
+  <xsd:attribute name="controller" default="AC97">
+    <xsd:simpleType>
+      <xsd:restriction base="xsd:token">
+        <xsd:enumeration value="AC97"/>
+        <xsd:enumeration value="SB16"/>
+        <xsd:enumeration value="HDA"/>
+      </xsd:restriction>
+    </xsd:simpleType>
+  </xsd:attribute>
+  <xsd:attribute name="driver" use="required">
+    <xsd:simpleType>
+      <xsd:restriction base="xsd:token">
+        <xsd:enumeration value="null"/> <!-- deprecated -->
+        <xsd:enumeration value="Null"/> <!-- all platforms -->
+        <xsd:enumeration value="OSS"/> <!-- Linux, Solaris, FreeBSD -->
+        <xsd:enumeration value="ALSA"/> <!-- Linux, FreeBSD -->
+        <xsd:enumeration value="Pulse"/> <!-- Linux -->
+        <xsd:enumeration value="CoreAudio"/> <!-- Mac OS X -->
+        <xsd:enumeration value="MMPM"/> <!-- OS/2 -->
+        <xsd:enumeration value="SolAudio"/> <!-- Solaris -->
+        <xsd:enumeration value="WinMM"/> <!-- Windows -->
+        <xsd:enumeration value="DirectSound"/> <!-- Windows -->
+      </xsd:restriction>
+    </xsd:simpleType>
+  </xsd:attribute>
+</xsd:complexType>
+
+<xsd:complexType name="TNetNAT">
+  <xsd:choice minOccurs="0" maxOccurs="unbounded">
+    <xsd:element name="DNS" minOccurs="0">
+      <xsd:complexType>
+        <xsd:attribute name="pass-domain" type="xsd:boolean" default="true"/>
+        <xsd:attribute name="use-proxy" type="xsd:boolean" default="false"/>
+        <xsd:attribute name="use-host-resolver" type="xsd:boolean" default="false"/>
+      </xsd:complexType>
+    </xsd:element>
+    <xsd:element name="Alias" minOccurs="0">
+      <xsd:complexType>
+        <xsd:attribute name="logging" type="xsd:boolean" default="false"/>
+        <xsd:attribute name="proxy-only" type="xsd:boolean" default="false"/>
+        <xsd:attribute name="use-same-ports" type="xsd:boolean" default="false"/>
+      </xsd:complexType>
+    </xsd:element>
+    <xsd:element name="TFTP" minOccurs="0">
+      <xsd:complexType>
+        <xsd:attribute name="prefix" type="xsd:string"/>
+        <xsd:attribute name="boot-file" type="xsd:string"/>
+        <xsd:attribute name="next-server" type="xsd:string"/>
+      </xsd:complexType>
+    </xsd:element>
+    <xsd:element name="Forwarding" minOccurs="0" maxOccurs="unbounded">
+      <xsd:complexType>
+        <xsd:attribute name="name" type="xsd:string"/>
+        <xsd:attribute name="proto" type="xsd:unsignedInt"/>
+        <xsd:attribute name="hostip" type="xsd:string"/>
+        <xsd:attribute name="hostport" type="xsd:unsignedInt"/>
+        <xsd:attribute name="guestip" type="xsd:string"/>
+        <xsd:attribute name="guestport" type="xsd:unsignedInt"/>
+      </xsd:complexType>
+    </xsd:element>
+  </xsd:choice>
+  <xsd:attribute name="network" type="xsd:string"/>
+  <xsd:attribute name="hostip" type="xsd:string"/>
+  <xsd:attribute name="mtu" type="xsd:unsignedInt"/>
+  <xsd:attribute name="sockrcv" type="xsd:unsignedInt"/>
+  <xsd:attribute name="socksnd" type="xsd:unsignedInt"/>
+  <xsd:attribute name="tcprcv" type="xsd:unsignedInt"/>
+  <xsd:attribute name="tcpsnd" type="xsd:unsignedInt"/>
+</xsd:complexType>
+
+<xsd:complexType name="TNetNATNetwork">
+  <xsd:attribute name="name" type="xsd:string"/>
+</xsd:complexType>
+
+<xsd:complexType name="TNetBridged">
+  <xsd:attribute name="name" type="xsd:string"/>
+</xsd:complexType>
+
+<xsd:complexType name="TNetInternal">
+  <xsd:attribute name="name" type="xsd:string"/>
+</xsd:complexType>
+
+<xsd:complexType name="TNetHostOnly">
+  <xsd:attribute name="name" type="xsd:string"/>
+</xsd:complexType>
+
+<xsd:complexType name="TNetGeneric">
+  <xsd:sequence>
+    <xsd:element name="Property" type="TProperty" minOccurs="0" maxOccurs="unbounded"/>
+  </xsd:sequence>
+  <xsd:attribute name="driver" type="xsd:string" use="required"/>
+</xsd:complexType>
+
+<xsd:complexType name="TNetworkConfig">
+  <xsd:choice maxOccurs="2">
+    <xsd:choice minOccurs="0">
+      <xsd:element name="NAT" type="TNetNAT"/>
+      <xsd:element name="NATNetwork" type="TNetNATNetwork"/>
+      <xsd:element name="HostInterface" type="TNetBridged"/>
+      <xsd:element name="BridgedInterface" type="TNetBridged"/>
+      <xsd:element name="InternalNetwork" type="TNetInternal"/>
+      <xsd:element name="HostOnlyInterface" type="TNetHostOnly"/>
+      <xsd:element name="GenericInterface" type="TNetGeneric"/>
+    </xsd:choice>
+    <xsd:element name="DisabledModes">
+      <xsd:complexType>
+        <xsd:all>
+          <xsd:element name="NAT" type="TNetNAT" minOccurs="0"/>
+          <xsd:element name="NATNetwork" type="TNetNATNetwork" minOccurs="0"/>
+          <xsd:element name="HostInterface" type="TNetBridged" minOccurs="0"/>
+          <xsd:element name="BridgedInterface" type="TNetBridged" minOccurs="0"/>
+          <xsd:element name="InternalNetwork" type="TNetInternal" minOccurs="0"/>
+          <xsd:element name="HostOnlyInterface" type="TNetHostOnly" minOccurs="0"/>
+          <xsd:element name="GenericInterface" type="TNetGeneric" minOccurs="0"/>
+        </xsd:all>
+      </xsd:complexType>
+    </xsd:element>
+  </xsd:choice>
+</xsd:complexType>
+
+<xsd:complexType name="TNetworkAdapter">
+  <xsd:complexContent>
+    <xsd:extension base="TNetworkConfig">
+      <xsd:attribute name="type" type="TNetworkAdapterType" default="Am79C973"/>
+      <xsd:attribute name="slot" type="xsd:unsignedInt" use="required"/>
+      <xsd:attribute name="enabled" type="xsd:boolean" default="false"/>
+      <xsd:attribute name="MACAddress">
+        <xsd:simpleType>
+          <xsd:restriction base="xsd:hexBinary">
+            <xsd:pattern value="[0-9A-Fa-f][02468ACEace][0-9A-Fa-f]{10}"/>
+          </xsd:restriction>
+        </xsd:simpleType>
+      </xsd:attribute>
+      <xsd:attribute name="cable" type="xsd:boolean" default="true"/>
+      <xsd:attribute name="speed" type="xsd:unsignedInt" default="1000000"/>
+      <xsd:attribute name="bootPriority" type="xsd:unsignedInt"/>
+      <xsd:attribute name="trace" type="xsd:boolean" default="false"/>
+      <xsd:attribute name="tracefile" type="xsd:string"/>
+      <xsd:attribute name="bandwidthGroup" type="xsd:string"/>
+      <xsd:attribute name="promiscuousModePolicy" default="Deny">
+        <xsd:simpleType>
+          <xsd:restriction base="xsd:token">
+            <xsd:enumeration value="Deny"/>
+            <xsd:enumeration value="AllowNetwork"/>
+            <xsd:enumeration value="AllowAll"/>
+          </xsd:restriction>
+        </xsd:simpleType>
+      </xsd:attribute>
+    </xsd:extension>
+  </xsd:complexContent>
+</xsd:complexType>
+
+<xsd:complexType name="TNetwork">
+  <xsd:sequence>
+    <xsd:element name="Adapter" type="TNetworkAdapter"
+                 minOccurs="0" maxOccurs="unbounded"/>
+  </xsd:sequence>
+</xsd:complexType>
+
+<xsd:complexType name="TUARTPort">
+  <xsd:attribute name="slot" use="required">
+    <xsd:simpleType>
+      <xsd:restriction base="xsd:unsignedInt">
+        <xsd:minInclusive value="0"/>
+        <xsd:maxExclusive value="4"/>
+      </xsd:restriction>
+    </xsd:simpleType>
+  </xsd:attribute>
+  <xsd:attribute name="enabled" type="xsd:boolean" use="required"/>
+  <xsd:attribute name="IRQ" type="TUInt8" use="required"/>
+  <xsd:attribute name="IOBase" type="TUInt16" use="required"/>
+  <xsd:attribute name="hostMode" type="TPortMode" use="required"/>
+  <xsd:attribute name="path" type="TLocalFile"/>
+  <xsd:attribute name="server" type="xsd:boolean" default="false"/>
+</xsd:complexType>
+
+<xsd:complexType name="TUART">
+  <xsd:sequence>
+    <xsd:element name="Port" type="TUARTPort"
+                 minOccurs="0" maxOccurs="unbounded"/>
+  </xsd:sequence>
+</xsd:complexType>
+
+<xsd:complexType name="TUartPort"> <!-- deprecated -->
+  <xsd:attribute name="slot" use="required">
+    <xsd:simpleType>
+      <xsd:restriction base="xsd:unsignedInt">
+        <xsd:minInclusive value="0"/>
+        <xsd:maxExclusive value="4"/>
+      </xsd:restriction>
+    </xsd:simpleType>
+  </xsd:attribute>
+  <xsd:attribute name="enabled" type="xsd:boolean" use="required"/>
+  <xsd:attribute name="IRQ" type="TUInt8" use="required"/>
+  <xsd:attribute name="IOBase" type="TUInt16HexNoBase" use="required"/>
+  <xsd:attribute name="hostMode" type="TPortMode" use="required"/>
+  <xsd:attribute name="path" type="TLocalFile"/>
+  <xsd:attribute name="server" type="xsd:boolean" default="false"/>
+</xsd:complexType>
+
+<xsd:complexType name="TUart"> <!-- deprecated -->
+  <xsd:sequence>
+    <xsd:element name="Port" type="TUartPort"
+                 minOccurs="0" maxOccurs="unbounded"/>
+  </xsd:sequence>
+</xsd:complexType>
+
+<xsd:complexType name="TLPTPort">
+  <xsd:attribute name="slot" use="required">
+    <xsd:simpleType>
+      <xsd:restriction base="xsd:unsignedInt">
+        <xsd:minInclusive value="0"/>
+        <xsd:maxExclusive value="2"/>
+      </xsd:restriction>
+    </xsd:simpleType>
+  </xsd:attribute>
+  <xsd:attribute name="enabled" type="xsd:boolean" use="required"/>
+  <xsd:attribute name="IRQ" type="TUInt8" use="required"/>
+  <xsd:attribute name="IOBase" type="TUInt16" use="required"/>
+  <xsd:attribute name="path" type="TLocalFile"/>
+</xsd:complexType>
+
+<xsd:complexType name="TLPT">
+  <xsd:sequence>
+    <xsd:element name="Port" type="TLPTPort"
+                 minOccurs="0" maxOccurs="unbounded"/>
+  </xsd:sequence>
+</xsd:complexType>
+
+<xsd:complexType name="TLptPort"> <!-- deprecated -->
+  <xsd:attribute name="slot" use="required">
+    <xsd:simpleType>
+      <xsd:restriction base="xsd:unsignedInt">
+        <xsd:minInclusive value="0"/>
+        <xsd:maxExclusive value="2"/>
+      </xsd:restriction>
+    </xsd:simpleType>
+  </xsd:attribute>
+  <xsd:attribute name="enabled" type="xsd:boolean" use="required"/>
+  <xsd:attribute name="IRQ" type="TUInt8" use="required"/>
+  <xsd:attribute name="IOBase" type="TUInt16HexNoBase" use="required"/>
+  <xsd:attribute name="path" type="TLocalFile"/>
+</xsd:complexType>
+
+<xsd:complexType name="TLpt">
+  <xsd:sequence>
+    <xsd:element name="Port" type="TLptPort"
+                 minOccurs="0" maxOccurs="unbounded"/>
+  </xsd:sequence>
+</xsd:complexType>
+
+<xsd:complexType name="TRTC">
+  <xsd:attribute name="localOrUTC" type="TLocalOrUTC" use="required"/>
+</xsd:complexType>
+
+<xsd:complexType name="TSharedFolder">
+  <xsd:attribute name="name" type="TNonEmptyString" use="required"/>
+  <xsd:attribute name="hostPath" type="TLocalFile" use="required"/>
+  <xsd:attribute name="writable" type="xsd:boolean" default="true"/>
+  <xsd:attribute name="autoMount" type="xsd:boolean" default="false"/>
+</xsd:complexType>
+
+<xsd:complexType name="TSharedFolders">
+  <xsd:sequence>
+    <xsd:element name="SharedFolder" type="TSharedFolder" minOccurs="0" maxOccurs="unbounded"/>
+  </xsd:sequence>
+</xsd:complexType>
+
+<xsd:complexType name="TClipboard">
+  <xsd:attribute name="mode" type="TClipboardMode" default="Disabled"/>
+</xsd:complexType>
+
+<xsd:complexType name="TDragAndDrop">
+  <xsd:attribute name="mode" type="TDragAndDropMode" use="required"/>
+</xsd:complexType>
+
+<xsd:complexType name="TIoCache">
+  <xsd:attribute name="enabled" type="xsd:boolean" default="true"/>
+  <xsd:attribute name="size" type="xsd:unsignedLong"/>
+</xsd:complexType>
+
+<xsd:complexType name="TBandwidthGroup">
+  <xsd:attribute name="name" type="xsd:token" use="required"/>
+  <xsd:attribute name="type" type="TBandwidthGroupType" use="required"/>
+  <xsd:attribute name="maxBytesPerSec" type="xsd:unsignedLong"/>
+  <xsd:attribute name="maxMbPerSec" type="xsd:unsignedLong"/>
+</xsd:complexType>
+
+<xsd:complexType name="TBandwidthGroups">
+  <xsd:sequence>
+    <xsd:element name="BandwidthGroup" type="TBandwidthGroup" minOccurs="0" maxOccurs="unbounded"/>
+  </xsd:sequence>
+</xsd:complexType>
+
+<xsd:complexType name="TIO">
+  <xsd:sequence>
+    <xsd:element name="IoCache" type="TIoCache" minOccurs="0"/>
+    <xsd:element name="BandwidthGroups" type="TBandwidthGroups" minOccurs="0"/>
+  </xsd:sequence>
+</xsd:complexType>
+
+<xsd:complexType name="THostPciDevice">
+  <xsd:attribute name="host" type="xsd:unsignedInt" use="required"/>
+  <xsd:attribute name="guest" type="xsd:unsignedInt" use="required"/>
+  <xsd:attribute name="name" type="xsd:token"/>
+</xsd:complexType>
+
+<xsd:complexType name="THostPciDevices">
+  <xsd:sequence>
+    <xsd:element name="Device" type="THostPciDevice" minOccurs="0" maxOccurs="unbounded"/>
+  </xsd:sequence>
+</xsd:complexType>
+
+<xsd:complexType name="THostPci">
+  <xsd:sequence>
+    <xsd:element name="Devices" type="THostPciDevices" minOccurs="0"/>
+  </xsd:sequence>
+</xsd:complexType>
+
+<xsd:complexType name="TCardReader">
+  <xsd:attribute name="enabled" type="xsd:boolean" default="false"/>
+</xsd:complexType>
+
+<xsd:complexType name="TWebcam">
+  <xsd:attribute name="enabled" type="xsd:boolean" default="false"/>
+</xsd:complexType>
+
+<xsd:complexType name="TEmulatedUSB">
+  <xsd:sequence>
+    <xsd:element name="CardReader" type="TCardReader" minOccurs="0"/>
+    <xsd:element name="Webcam" type="TWebcam" minOccurs="0"/>
+  </xsd:sequence>
+</xsd:complexType>
+
+<xsd:complexType name="TGuest">
+  <xsd:attribute name="memoryBalloonSize"        type="xsd:unsignedInt" default="0"/>
+  <xsd:attribute name="MemoryBalloonSize"        type="xsd:unsignedInt" default="0"/> <!-- deprecated -->
+  <xsd:attribute name="statisticsUpdateInterval" type="xsd:unsignedInt" default="0"/>
+  <xsd:attribute name="StatisticsUpdateInterval" type="xsd:unsignedInt" default="0"/> <!-- deprecated -->
+</xsd:complexType>
+
+<xsd:complexType name="TGuestProperty">
+  <xsd:attribute name="name"      type="xsd:string"       use="required"/>
+  <xsd:attribute name="value"     type="xsd:string"       use="required"/>
+  <xsd:attribute name="timestamp" type="xsd:unsignedLong" default="0"/>
+  <xsd:attribute name="flags"     type="xsd:string"       default=""/>
+</xsd:complexType>
+
+<xsd:complexType name="TGuestProperties">
+  <xsd:sequence>
+    <xsd:element name="GuestProperty" type="TGuestProperty" minOccurs="0" maxOccurs="unbounded"/>
+  </xsd:sequence>
+  <xsd:attribute name="notificationPatterns" type="xsd:string" default=""/>
+</xsd:complexType>
+
+<xsd:complexType name="TMemory">
+  <xsd:attribute name="RAMSize" use="required">
+    <xsd:simpleType>
+      <xsd:restriction base="xsd:unsignedInt">
+        <xsd:minInclusive value="4"/>
+        <xsd:maxInclusive value="2097152"/>
+      </xsd:restriction>
+    </xsd:simpleType>
+  </xsd:attribute>
+  <xsd:attribute name="PageFusion" type="xsd:boolean" default="false"/>
+</xsd:complexType>
+
+<xsd:complexType name="TFirmware">
+  <xsd:attribute name="type" use="required">
+    <xsd:simpleType>
+      <xsd:restriction base="xsd:token">
+        <xsd:enumeration value="BIOS"/>
+        <xsd:enumeration value="EFI"/>
+        <xsd:enumeration value="EFI32"/>
+        <xsd:enumeration value="EFI64"/>
+        <xsd:enumeration value="EFIDUAL"/>
+      </xsd:restriction>
+    </xsd:simpleType>
+  </xsd:attribute>
+</xsd:complexType>
+
+<xsd:complexType name="THID">
+  <xsd:attribute name="Pointing" default="PS2Mouse">
+    <xsd:simpleType>
+      <xsd:restriction base="xsd:token">
+        <xsd:enumeration value="USBMouse"/>
+        <xsd:enumeration value="USBTablet"/>
+        <xsd:enumeration value="PS2Mouse"/>
+        <xsd:enumeration value="ComboMouse"/>
+      </xsd:restriction>
+    </xsd:simpleType>
+  </xsd:attribute>
+  <xsd:attribute name="Keyboard" default="PS2Keyboard">
+    <xsd:simpleType>
+      <xsd:restriction base="xsd:token">
+        <xsd:enumeration value="USBKeyboard"/>
+        <xsd:enumeration value="PS2Keyboard"/>
+        <xsd:enumeration value="ComboKeyboard"/>
+      </xsd:restriction>
+    </xsd:simpleType>
+  </xsd:attribute>
+</xsd:complexType>
+
+<xsd:complexType name="THPET">
+  <xsd:attribute name="enabled" type="xsd:boolean" default="false"/>
+</xsd:complexType>
+
+<xsd:complexType name="TChipset">
+  <xsd:attribute name="type" use="required">
+    <xsd:simpleType>
+      <xsd:restriction base="xsd:token">
+        <xsd:enumeration value="PIIX3"/>
+        <xsd:enumeration value="ICH9"/>
+      </xsd:restriction>
+    </xsd:simpleType>
+  </xsd:attribute>
+</xsd:complexType>
+
+<xsd:complexType name="TParavirt">
+  <xsd:attribute name="provider" use="required">
+    <xsd:simpleType>
+      <xsd:restriction base="xsd:token">
+        <xsd:enumeration value="None"/>
+        <xsd:enumeration value="Default"/>
+        <xsd:enumeration value="Legacy"/>
+        <xsd:enumeration value="Minimal"/>
+        <xsd:enumeration value="HyperV"/>
+        <xsd:enumeration value="KVM"/>
+      </xsd:restriction>
+    </xsd:simpleType>
+  </xsd:attribute>
+  <xsd:attribute name="debug" type="xsd:string"/>
+</xsd:complexType>
+
+<xsd:complexType name="TTeleporter">
+  <xsd:attribute name="enabled" type="xsd:boolean" default="false"/>
+  <xsd:attribute name="port" type="xsd:unsignedShort"/>
+  <xsd:attribute name="address" type="xsd:string"/>
+  <xsd:attribute name="password" type="xsd:string"/>
+</xsd:complexType>
+
+<xsd:complexType name="THardware">
+  <xsd:all>
+    <xsd:element name="CPU" type="TCPU" minOccurs="0"/>
+    <xsd:element name="Memory" type="TMemory"/>
+    <xsd:element name="Firmware" type="TFirmware" minOccurs="0"/>
+    <xsd:element name="HID" type="THID" minOccurs="0"/>
+    <xsd:element name="HPET" type="THPET" minOccurs="0"/>
+    <xsd:element name="Chipset" type="TChipset" minOccurs="0"/>
+    <xsd:element name="Paravirt" type="TParavirt" minOccurs="0"/>
+    <xsd:element name="Boot" type="TBoot" minOccurs="0">
+      <xsd:unique name="THardware-Boot-Order">
+        <xsd:selector xpath="vb:Order"/>
+        <xsd:field xpath="@position"/>
+      </xsd:unique>
+    </xsd:element>
+    <xsd:element name="Display" type="TDisplay" minOccurs="0"/>
+    <xsd:element name="VideoRecording" type="TVideoRecording" minOccurs="0"/>
+    <xsd:element name="VideoCapture" type="TVideoCapture" minOccurs="0"/>
+    <xsd:element name="RemoteDisplay" type="TRemoteDisplay" minOccurs="0"/>
+    <xsd:element name="BIOS" type="TBIOS" minOccurs="0"/>
+    <xsd:element name="DVDDrive" type="TDVDDrive" minOccurs="0"/>
+    <xsd:element name="FloppyDrive" type="TFloppyDrive" minOccurs="0"/>
+    <xsd:element name="USBController" type="TUSBController" minOccurs="0"/>
+    <xsd:element name="USB" type="TUSB" minOccurs="0"/>
+    <xsd:element name="SATAController" type="TSATAController" minOccurs="0"/> <!-- deprecated -->
+    <xsd:element name="Network" type="TNetwork" minOccurs="0">
+      <xsd:unique name="THardware-Network-Adapter">
+        <xsd:selector xpath="vb:Adapter"/>
+        <xsd:field xpath="@slot"/>
+      </xsd:unique>
+    </xsd:element>
+    <xsd:element name="UART" type="TUART" minOccurs="0">
+      <xsd:unique name="THardware-UART-Port">
+        <xsd:selector xpath="vb:Port"/>
+        <xsd:field xpath="@slot"/>
+      </xsd:unique>
+    </xsd:element>
+    <xsd:element name="Uart" type="TUart" minOccurs="0"> <!-- deprecated -->
+      <xsd:unique name="THardware-Uart-Port">
+        <xsd:selector xpath="vb:Port"/>
+        <xsd:field xpath="@slot"/>
+      </xsd:unique>
+    </xsd:element>
+    <xsd:element name="LPT" type="TLPT" minOccurs="0">
+      <xsd:unique name="THardware-LPT-Port">
+        <xsd:selector xpath="vb:Port"/>
+        <xsd:field xpath="@slot"/>
+      </xsd:unique>
+    </xsd:element>
+    <xsd:element name="Lpt" type="TLpt" minOccurs="0"> <!-- deprecated -->
+      <xsd:unique name="THardware-Lpt-Port">
+        <xsd:selector xpath="vb:Port"/>
+        <xsd:field xpath="@slot"/>
+      </xsd:unique>
+    </xsd:element>
+    <xsd:element name="AudioAdapter" type="TAudioAdapter" minOccurs="0"/>
+    <xsd:element name="RTC" type="TRTC" minOccurs="0"/>
+    <xsd:element name="SharedFolders" type="TSharedFolders" minOccurs="0">
+      <xsd:unique name="THardware-SharedFolders-SharedFolder">
+        <xsd:selector xpath="vb:SharedFolder"/>
+        <xsd:field xpath="@name"/>
+      </xsd:unique>
+    </xsd:element>
+    <xsd:element name="Clipboard" type="TClipboard" minOccurs="0"/>
+    <xsd:element name="DragAndDrop" type="TDragAndDrop" minOccurs="0"/>
+    <xsd:element name="IO" type="TIO" minOccurs="0"/>
+    <xsd:element name="HostPci" type="THostPci" minOccurs="0"/>
+    <xsd:element name="EmulatedUSB" type="TEmulatedUSB" minOccurs="0"/>
+    <xsd:element name="Guest" type="TGuest" minOccurs="0"/>
+    <xsd:element name="GuestProperties" type="TGuestProperties" minOccurs="0">
+      <xsd:unique name="THardware-GuestProperties-GuestProperty">
+        <xsd:selector xpath="vb:GuestProperty"/>
+        <xsd:field xpath="@name"/>
+      </xsd:unique>
+    </xsd:element>
+    <xsd:element name="StorageControllers" type="TStorageControllers" minOccurs="0"/>
+  </xsd:all>
+  <xsd:attribute name="version" type="xsd:string" default="2"/>
+</xsd:complexType>
+
+<xsd:complexType name="TGroup">
+  <xsd:attribute name="name" type="xsd:string" use="required"/>
+</xsd:complexType>
+
+<xsd:complexType name="TGroups">
+  <xsd:sequence>
+    <xsd:element name="Group" type="TGroup" minOccurs="0" maxOccurs="unbounded"/>
+  </xsd:sequence>
+</xsd:complexType>
+
+<xsd:complexType name="TMachine">
+  <xsd:all>
+    <xsd:element name="MediaRegistry" type="TMediaRegistry" minOccurs="0"/>
+    <xsd:element name="Description" type="xsd:string" minOccurs="0"/>
+    <xsd:element name="Teleporter" type="TTeleporter" minOccurs="0"/>
+    <xsd:element name="Hardware" type="THardware"/>
+    <xsd:element name="StorageControllers" type="TStorageControllers" minOccurs="0"/>
+    <xsd:element name="HardDiskAttachments" type="THardDiskAttachments" minOccurs="0"/> <!-- deprecated -->
+    <xsd:element name="Groups" type="TGroups" minOccurs="0"/>
+    <xsd:element name="ExtraData" type="TExtraData" minOccurs="0"/>
+    <xsd:element name="Snapshot" type="TSnapshot" minOccurs="0"/>
+  </xsd:all>
+  <xsd:attribute name="name" type="TNonEmptyString" use="required"/>
+  <xsd:attribute name="nameSync" type="xsd:boolean" default="true"/>
+  <xsd:attribute name="directoryIncludesUUID" type="xsd:boolean" default="false"/>
+  <xsd:attribute name="OSType" type="TNonEmptyString" use="required"/>
+  <xsd:attribute name="uuid" type="TNonNullUUID" use="required"/>
+  <xsd:attribute name="stateFile" type="TLocalFile"/>
+  <xsd:attribute name="currentSnapshot" type="TNonNullUUID"/>
+  <xsd:attribute name="snapshotFolder" type="TLocalFile"/>
+  <xsd:attribute name="lastStateChange" type="TPresentDateTimeUTC"/>
+  <xsd:attribute name="aborted" type="xsd:boolean" default="false"/>
+  <xsd:attribute name="currentStateModified" type="xsd:boolean" default="true"/>
+  <xsd:attribute name="version" type="xsd:string" default="1.15"/> <!-- Used for OVF files only, must not be present in normal settings files. The default corresponds to settings created by 5.0, which covers many older versions but not newer ones. -->
+  <xsd:attribute name="VMProcessPriority" type="TVMProcPriority"/>
+</xsd:complexType>
+
+<xsd:complexType name="TSnapshot">
+  <xsd:all>
+    <xsd:element name="Description" type="xsd:string" minOccurs="0"/>
+    <xsd:element name="Hardware" type="THardware"/>
+    <xsd:element name="StorageControllers" type="TStorageControllers" minOccurs="0"/>
+    <xsd:element name="Snapshots" minOccurs="0">
+      <xsd:complexType>
+        <xsd:sequence>
+          <xsd:element name="Snapshot" type="TSnapshot" minOccurs="0" maxOccurs="unbounded"/>
+        </xsd:sequence>
+      </xsd:complexType>
+    </xsd:element>
+  </xsd:all>
+  <xsd:attribute name="name" type="xsd:token" use="required"/>
+  <xsd:attribute name="uuid" type="TNonNullUUID" use="required"/>
+  <xsd:attribute name="timeStamp" type="TPresentDateTimeUTC" use="required"/>
+  <xsd:attribute name="stateFile" type="TLocalFile"/>
+</xsd:complexType>
+
+<xsd:complexType name="TVirtualBox">
+  <xsd:choice>
+    <xsd:element name="Global" type="TGlobal"/>
+    <xsd:element name="Machine" type="TMachine">
+      <!-- @currentSnapshot must refer to an existing Snapshot/@uuid -->
+      <xsd:key name="snapshot">
+        <xsd:selector xpath=".//vb:Snapshot"/>
+        <xsd:field xpath="@uuid"/>
+      </xsd:key>
+      <xsd:keyref name="currentSnapshot" refer="vb:snapshot">
+        <xsd:selector xpath="."/>
+        <xsd:field xpath="@currentSnapshot"/>
+      </xsd:keyref>
+    </xsd:element>
+  </xsd:choice>
+  <xsd:attribute name="version" type="xsd:string" use="required"/>
+</xsd:complexType>
+
+<!-- Root element for all VirtualBox config files -->
+<xsd:element name="VirtualBox" type="TVirtualBox"/>
+
+</xsd:schema>
diff --git a/src/VBox/Main/xml/ovfreader.cpp b/src/VBox/Main/xml/ovfreader.cpp
new file mode 100644
index 00000000..49173538
--- /dev/null
+++ b/src/VBox/Main/xml/ovfreader.cpp
@@ -0,0 +1,1090 @@
+/* $Id: ovfreader.cpp $ */
+/** @file
+ * OVF reader declarations.
+ *
+ * Depends only on IPRT, including the RTCString and IPRT XML classes.
+ */
+
+/*
+ * Copyright (C) 2008-2023 Oracle and/or its affiliates.
+ *
+ * This file is part of VirtualBox base platform packages, as
+ * available from https://www.virtualbox.org.
+ *
+ * This program is free software; you can redistribute it and/or
+ * modify it under the terms of the GNU General Public License
+ * as published by the Free Software Foundation, in version 3 of the
+ * License.
+ *
+ * This program is distributed in the hope that it will be useful, but
+ * WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
+ * General Public License for more details.
+ *
+ * You should have received a copy of the GNU General Public License
+ * along with this program; if not, see <https://www.gnu.org/licenses>.
+ *
+ * SPDX-License-Identifier: GPL-3.0-only
+ */
+
+#define LOG_GROUP LOG_GROUP_MAIN_APPLIANCE
+#include "ovfreader.h"
+#include <VBox/log.h>
+#include <vector>
+
+using namespace std;
+using namespace ovf;
+
+
+
+////////////////////////////////////////////////////////////////////////////////
+//
+// OVF reader implementation
+//
+////////////////////////////////////////////////////////////////////////////////
+
+/**
+ * Default Constructor.
+ * Should be used if you don't have an OVF file, but want to fill the data
+ * m_mapDisks, m_llVirtualSystems manually
+ */
+OVFReader::OVFReader()
+{
+}
+
+/**
+ * Constructor. This parses the given XML file out of the memory. Throws lots of exceptions
+ * on XML or OVF invalidity.
+ * @param pvBuf  the memory buffer to parse
+ * @param cbSize the size of the memory buffer
+ * @param path   path to a filename for error messages.
+ */
+OVFReader::OVFReader(const void *pvBuf, size_t cbSize, const RTCString &path)
+    : m_strPath(path)
+{
+    xml::XmlMemParser parser;
+    parser.read(pvBuf, cbSize,
+                m_strPath,
+                m_doc);
+    /* Start the parsing */
+    parse();
+}
+
+/**
+ * Constructor. This opens the given XML file and parses it. Throws lots of exceptions
+ * on XML or OVF invalidity.
+ * @param path
+ */
+OVFReader::OVFReader(const RTCString &path)
+    : m_strPath(path)
+{
+    xml::XmlFileParser parser;
+    parser.read(m_strPath,
+                m_doc);
+    /* Start the parsing */
+    parse();
+}
+
+void OVFReader::parse()
+{
+    const xml::ElementNode *pRootElem = m_doc.getRootElement();
+    const xml::AttributeNode *pTypeAttr;
+    const char *pcszTypeAttr = "";
+    RTCString pcszNamespaceURI;
+
+    if (!pRootElem || strcmp(pRootElem->getName(), "Envelope"))
+        throw OVFLogicError(N_("Root element in OVF file must be 'Envelope'."));
+
+    pcszNamespaceURI = pRootElem->getNamespaceURI();
+    if (pcszNamespaceURI.isEmpty())
+    {
+        throw OVFLogicError(N_("Error reading namespace URI in 'Envelope' element, line %d"), pRootElem->getLineNumber());
+    }
+
+    if (strncmp(ovf::OVF20_URI_string, pcszNamespaceURI.c_str(), pcszNamespaceURI.length()) == 0)
+    {
+        m_envelopeData.setOVFVersion(ovf::OVFVersion_2_0);
+    }
+    else if (strncmp(OVF10_URI_string, pcszNamespaceURI.c_str(), pcszNamespaceURI.length()) == 0)
+    {
+        m_envelopeData.setOVFVersion(ovf::OVFVersion_1_0);
+    }
+    else
+    {
+        m_envelopeData.setOVFVersion(ovf::OVFVersion_0_9);
+    }
+
+    if ((pTypeAttr = pRootElem->findAttribute("lang", "xml")))
+    {
+        pcszTypeAttr = pTypeAttr->getValueN(RT_XML_ATTR_TINY);
+        m_envelopeData.lang = pcszTypeAttr;
+    }
+
+    // OVF has the following rough layout:
+    /*
+        -- <References> ....  files referenced from other parts of the file, such as VMDK images
+        -- Metadata, comprised of several section commands
+        -- virtual machines, either a single <VirtualSystem>, or a <VirtualSystemCollection>
+        -- optionally <Strings> for localization
+    */
+
+    // get all "File" child elements of "References" section so we can look up files easily;
+    // first find the "References" sections so we can look up files
+    xml::ElementNodesList listFileElements;      // receives all /Envelope/References/File nodes
+    const xml::ElementNode *pReferencesElem;
+    if ((pReferencesElem = pRootElem->findChildElement("References")))
+        pReferencesElem->getChildElements(listFileElements, "File");
+
+    // now go though the sections
+    LoopThruSections(pReferencesElem, pRootElem);
+}
+
+/**
+ * Private helper method that goes thru the elements of the given "current" element in the OVF XML
+ * and handles the contained child elements (which can be "Section" or "Content" elements).
+ *
+ * @param pReferencesElem "References" element from OVF, for looking up file specifications;
+ *                        can be NULL if no such element is present.
+ * @param pCurElem Element whose children are to be analyzed here.
+ */
+void OVFReader::LoopThruSections(const xml::ElementNode *pReferencesElem,
+                                 const xml::ElementNode *pCurElem)
+{
+    xml::NodesLoop loopChildren(*pCurElem);
+    const xml::ElementNode *pElem;
+    while ((pElem = loopChildren.forAllNodes()))
+    {
+        const char *pcszElemName = pElem->getName();
+        const xml::AttributeNode *pTypeAttr = pElem->findAttribute("type");
+        const char *pcszTypeAttr = pTypeAttr ? pTypeAttr->getValueN(RT_XML_ATTR_TINY) : "";
+
+        if (    !strcmp(pcszElemName, "DiskSection")
+             || (    !strcmp(pcszElemName, "Section")
+                  && !strcmp(pcszTypeAttr, "ovf:DiskSection_Type")
+                )
+           )
+        {
+            HandleDiskSection(pReferencesElem, pElem);
+        }
+        else if (    !strcmp(pcszElemName, "NetworkSection")
+                  || (    !strcmp(pcszElemName, "Section")
+                       && !strcmp(pcszTypeAttr, "ovf:NetworkSection_Type")
+                     )
+                )
+        {
+            HandleNetworkSection(pElem);
+        }
+        else if (    !strcmp(pcszElemName, "DeploymentOptionSection"))
+        {
+            /// @todo
+        }
+        else if (    !strcmp(pcszElemName, "Info"))
+        {
+            // child of VirtualSystemCollection -- TODO
+        }
+        else if (    !strcmp(pcszElemName, "ResourceAllocationSection"))
+        {
+            // child of VirtualSystemCollection -- TODO
+        }
+        else if (    !strcmp(pcszElemName, "StartupSection"))
+        {
+            // child of VirtualSystemCollection -- TODO
+        }
+        else if (    !strcmp(pcszElemName, "VirtualSystem")
+                  || (    !strcmp(pcszElemName, "Content")
+                       && !strcmp(pcszTypeAttr, "ovf:VirtualSystem_Type")
+                     )
+                )
+        {
+            HandleVirtualSystemContent(pElem);
+        }
+        else if (    !strcmp(pcszElemName, "VirtualSystemCollection")
+                  || (    !strcmp(pcszElemName, "Content")
+                       && !strcmp(pcszTypeAttr, "ovf:VirtualSystemCollection_Type")
+                     )
+                )
+        {
+            /// @todo ResourceAllocationSection
+
+            // recurse for this, since it has VirtualSystem elements as children
+            LoopThruSections(pReferencesElem, pElem);
+        }
+    }
+}
+
+/**
+ * Private helper method that handles disk sections in the OVF XML.
+ *
+ * Gets called indirectly from IAppliance::read().
+ *
+ * @param pReferencesElem   "References" element from OVF, for looking up file
+ *                          specifications; can be NULL if no such element is
+ *                          present.
+ * @param pSectionElem      Section element for which this helper is getting called.
+ */
+void OVFReader::HandleDiskSection(const xml::ElementNode *pReferencesElem,
+                                  const xml::ElementNode *pSectionElem)
+{
+    // contains "Disk" child elements
+    xml::NodesLoop loopDisks(*pSectionElem, "Disk");
+    const xml::ElementNode *pelmDisk;
+    while ((pelmDisk = loopDisks.forAllNodes()))
+    {
+        DiskImage d;
+        const char *pcszBad = NULL;
+        const char *pcszDiskId;
+        const char *pcszFormat;
+        if (!pelmDisk->getAttributeValueN("diskId", pcszDiskId, RT_XML_ATTR_TINY))
+            pcszBad = "diskId";
+        else if (!pelmDisk->getAttributeValueN("format", pcszFormat, RT_XML_ATTR_SMALL))
+            pcszBad = "format";
+        else if (!pelmDisk->getAttributeValue("capacity", d.iCapacity))
+            pcszBad = "capacity";
+        else
+        {
+            d.strDiskId = pcszDiskId;
+            d.strFormat = pcszFormat;
+
+            if (!pelmDisk->getAttributeValue("populatedSize", d.iPopulatedSize))
+                // optional
+                d.iPopulatedSize = -1;
+
+            // optional vbox:uuid attribute (if OVF was exported by VirtualBox != 3.2)
+            pelmDisk->getAttributeValueN("uuid", d.uuidVBox, RT_XML_ATTR_TINY, "vbox");
+
+            const char *pcszFileRef;
+            if (pelmDisk->getAttributeValueN("fileRef", pcszFileRef, RT_XML_ATTR_SMALL)) // optional
+            {
+                // look up corresponding /References/File nodes (list built above)
+                const xml::ElementNode *pFileElem;
+                if (    pReferencesElem
+                     && (pFileElem = pReferencesElem->findChildElementFromId(pcszFileRef)) != NULL
+                   )
+                {
+
+                    // copy remaining values from file node then
+                    const char *pcszBadInFile = NULL;
+                    const char *pcszHref;
+                    if (!pFileElem->getAttributeValueN("href", pcszHref, RT_XML_ATTR_SMALL))
+                        pcszBadInFile = "href";
+                    else if (!pFileElem->getAttributeValue("size", d.iSize))
+                        d.iSize = -1;       // optional
+
+                    d.strHref = pcszHref;
+
+                    // if (!(pFileElem->getAttributeValue("size", d.iChunkSize))) TODO
+                    d.iChunkSize = -1;       // optional
+                    const char *pcszCompression;
+                    if (pFileElem->getAttributeValueN("compression", pcszCompression, RT_XML_ATTR_TINY))
+                        d.strCompression = pcszCompression;
+
+                    if (pcszBadInFile)
+                        throw OVFLogicError(N_("Error reading \"%s\": missing or invalid attribute '%s' in 'File' element, line %d"),
+                                            m_strPath.c_str(),
+                                            pcszBadInFile,
+                                            pFileElem->getLineNumber());
+                }
+                else
+                    throw OVFLogicError(N_("Error reading \"%s\": cannot find References/File element for ID \"%s\" referenced by 'Disk' element, line %d"),
+                                        m_strPath.c_str(),
+                                        pcszFileRef,
+                                        pelmDisk->getLineNumber());
+            }
+        }
+
+        if (pcszBad)
+            throw OVFLogicError(N_("Error reading \"%s\": missing or invalid attribute '%s' in 'DiskSection' element, line %d"),
+                                m_strPath.c_str(),
+                                pcszBad,
+                                pelmDisk->getLineNumber());
+
+        // suggest a size in megabytes to help callers with progress reports
+        d.ulSuggestedSizeMB = 0;
+        if (d.iCapacity != -1)
+            d.ulSuggestedSizeMB = (uint32_t)(d.iCapacity / _1M);
+        else if (d.iPopulatedSize != -1)
+            d.ulSuggestedSizeMB = (uint32_t)(d.iPopulatedSize / _1M);
+        else if (d.iSize != -1)
+            d.ulSuggestedSizeMB = (uint32_t)(d.iSize / _1M);
+        if (d.ulSuggestedSizeMB == 0)
+            d.ulSuggestedSizeMB = 10000;         // assume 10 GB, this is for the progress bar only anyway
+
+        m_mapDisks[d.strDiskId] = d;
+    }
+}
+
+/**
+ * Private helper method that handles network sections in the OVF XML.
+ * Gets called indirectly from IAppliance::read().
+ */
+void OVFReader::HandleNetworkSection(const xml::ElementNode * /* pSectionElem */)
+{
+    // we ignore network sections for now
+
+//     xml::NodesLoop loopNetworks(*pSectionElem, "Network");
+//     const xml::Node *pelmNetwork;
+//     while ((pelmNetwork = loopNetworks.forAllNodes()))
+//     {
+//         Network n;
+//         if (!(pelmNetwork->getAttributeValue("name", n.strNetworkName)))
+//             return setError(VBOX_E_FILE_ERROR,
+//                             tr("Error reading \"%s\": missing 'name' attribute in 'Network', line %d"),
+//                             pcszPath,
+//                             pelmNetwork->getLineNumber());
+//
+//         m->mapNetworks[n.strNetworkName] = n;
+//     }
+}
+
+/**
+ * Private helper method that handles a "VirtualSystem" element in the OVF XML.
+ * Gets called indirectly from IAppliance::read().
+ *
+ * @param pelmVirtualSystem
+ */
+void OVFReader::HandleVirtualSystemContent(const xml::ElementNode *pelmVirtualSystem)
+{
+    /* Create a new virtual system and work directly on the list copy. */
+    m_llVirtualSystems.push_back(VirtualSystem());
+    VirtualSystem &vsys = m_llVirtualSystems.back();
+
+    // peek under the <VirtualSystem> node whether we have a <vbox:Machine> node;
+    // that case case, the caller can completely ignore the OVF but only load the VBox machine XML
+    vsys.pelmVBoxMachine = pelmVirtualSystem->findChildElementNS("vbox", "Machine");
+
+    // now look for real OVF
+    const xml::AttributeNode *pIdAttr = pelmVirtualSystem->findAttribute("id");
+    if (pIdAttr)
+        vsys.strName = pIdAttr->getValueN(RT_XML_ATTR_SMALL);
+
+    xml::NodesLoop loop(*pelmVirtualSystem);      // all child elements
+    const xml::ElementNode *pelmThis;
+    while ((pelmThis = loop.forAllNodes()))
+    {
+        const char *pcszElemName = pelmThis->getName();
+        const char *pcszTypeAttr = "";
+        if (!strcmp(pcszElemName, "Section"))       // OVF 0.9 used "Section" element always with a varying "type" attribute
+        {
+            const xml::AttributeNode *pTypeAttr = pelmThis->findAttribute("type");
+            if (pTypeAttr)
+                pcszTypeAttr = pTypeAttr->getValueN(RT_XML_ATTR_TINY);
+            else
+                throw OVFLogicError(N_("Error reading \"%s\": element 'Section' has no 'type' attribute, line %d"),
+                                    m_strPath.c_str(),
+                                    pelmThis->getLineNumber());
+        }
+
+        if (    !strcmp(pcszElemName, "EulaSection")
+             || !strcmp(pcszTypeAttr, "ovf:EulaSection_Type")
+           )
+        {
+         /* <EulaSection>
+                <Info ovf:msgid="6">License agreement for the Virtual System.</Info>
+                <License ovf:msgid="1">License terms can go in here.</License>
+            </EulaSection> */
+
+            const xml::ElementNode *pelmLicense;
+            if ((pelmLicense = pelmThis->findChildElement("License")))
+                vsys.strLicenseText = pelmLicense->getValueN(RT_XML_CONTENT_LARGE);
+        }
+        if (    !strcmp(pcszElemName, "ProductSection")
+             || !strcmp(pcszTypeAttr, "ovf:ProductSection_Type")
+           )
+        {
+            /* <Section ovf:required="false" xsi:type="ovf:ProductSection_Type">
+                <Info>Meta-information about the installed software</Info>
+                <Product>VAtest</Product>
+                <Vendor>SUN Microsystems</Vendor>
+                <Version>10.0</Version>
+                <ProductUrl>http://blogs.sun.com/VirtualGuru</ProductUrl>
+                <VendorUrl>http://www.sun.com</VendorUrl>
+               </Section> */
+            const xml::ElementNode *pelmProduct;
+            if ((pelmProduct = pelmThis->findChildElement("Product")))
+                vsys.strProduct = pelmProduct->getValueN(RT_XML_CONTENT_SMALL);
+            const xml::ElementNode *pelmVendor;
+            if ((pelmVendor = pelmThis->findChildElement("Vendor")))
+                vsys.strVendor = pelmVendor->getValueN(RT_XML_CONTENT_SMALL);
+            const xml::ElementNode *pelmVersion;
+            if ((pelmVersion = pelmThis->findChildElement("Version")))
+                vsys.strVersion = pelmVersion->getValueN(RT_XML_CONTENT_SMALL);
+            const xml::ElementNode *pelmProductUrl;
+            if ((pelmProductUrl = pelmThis->findChildElement("ProductUrl")))
+                vsys.strProductUrl = pelmProductUrl->getValueN(RT_XML_CONTENT_SMALL);
+            const xml::ElementNode *pelmVendorUrl;
+            if ((pelmVendorUrl = pelmThis->findChildElement("VendorUrl")))
+                vsys.strVendorUrl = pelmVendorUrl->getValueN(RT_XML_CONTENT_SMALL);
+        }
+        else if (    !strcmp(pcszElemName, "VirtualHardwareSection")
+                  || !strcmp(pcszTypeAttr, "ovf:VirtualHardwareSection_Type")
+                )
+        {
+            const xml::ElementNode *pelmSystem, *pelmVirtualSystemType;
+            if ((pelmSystem = pelmThis->findChildElement("System")))
+            {
+             /* <System>
+                    <vssd:Description>Description of the virtual hardware section.</vssd:Description>
+                    <vssd:ElementName>vmware</vssd:ElementName>
+                    <vssd:InstanceID>1</vssd:InstanceID>
+                    <vssd:VirtualSystemIdentifier>MyLampService</vssd:VirtualSystemIdentifier>
+                    <vssd:VirtualSystemType>vmx-4</vssd:VirtualSystemType>
+                </System>*/
+                if ((pelmVirtualSystemType = pelmSystem->findChildElement("VirtualSystemType")))
+                    vsys.strVirtualSystemType = pelmVirtualSystemType->getValueN(RT_XML_CONTENT_SMALL);
+            }
+
+            /* Parse the items into the hardware item vector. */
+            {
+                std::map<RTCString, const VirtualHardwareItem *> mapHardwareItems;
+                xml::NodesLoop childrenIterator(*pelmThis);
+                const xml::ElementNode *pelmItem;
+                while ((pelmItem = childrenIterator.forAllNodes()) != NULL)
+                {
+                    /* Parse according to type. */
+                    VirtualHardwareItem *pItem;
+                    const char *pszName = pelmItem->getName();
+                    if (RTStrCmp(pszName, "Item") == 0)
+                        pItem = new VirtualHardwareItem();
+                    else if (RTStrCmp(pszName, "StorageItem") == 0)
+                        pItem = new StorageItem();
+                    else if (RTStrCmp(pszName, "EthernetPortItem") == 0)
+                        pItem = new EthernetPortItem();
+                    else
+                        continue;
+                    vsys.vecHardwareItems.push_back(pItem);
+                    pItem->m_iLineNumber = pelmItem->getLineNumber();
+                    pItem->fillItem(pelmItem);
+
+                    /* validate */
+                    try
+                    {
+                        pItem->checkConsistencyAndCompliance();
+                    }
+                    catch (OVFLogicError &e)
+                    {
+                        throw OVFLogicError(N_("Error reading \"%s\": \"%s\""), m_strPath.c_str(), e.what());
+                    }
+
+                    /* Add to mapping vector (for parent ID lookups) if it has a valid instance ID. */
+                    if (!pItem->strInstanceID.isEmpty())
+                    {
+                        std::map<RTCString, const VirtualHardwareItem *>::const_iterator itDup;
+                        itDup = mapHardwareItems.find(pItem->strInstanceID);
+                        if (itDup == mapHardwareItems.end())
+                            mapHardwareItems[pItem->strInstanceID] = pItem;
+                        else
+#if 1
+                            LogRel(("OVFREADER: Warning reading \"%s\": Duplicate InstanceID \"%s\" on line %d, previous at %d!\n",
+                                    m_strPath.c_str(), pItem->strInstanceID.c_str(), pItem->m_iLineNumber, itDup->second->m_iLineNumber));
+#else
+                            throw OVFLogicError(N_("Error reading \"%s\": Duplicate InstanceID \"%s\" on line %d, previous at %d"),
+                                                m_strPath.c_str(), pItem->strInstanceID.c_str(),
+                                                pItem->m_iLineNumber, itDup->second->m_iLineNumber);
+#endif
+                    }
+                }
+            }
+
+            HardDiskController *pPrimaryIDEController = NULL;// will be set once found
+
+            // now go thru all hardware items and handle them according to their type;
+            // in this first loop we handle all items _except_ hard disk images,
+            // which we'll handle in a second loop below
+            HardwareItemVector::const_iterator itH;
+            for (itH = vsys.vecHardwareItems.begin(); itH != vsys.vecHardwareItems.end(); ++itH)
+            {
+                const VirtualHardwareItem &i = **itH;
+
+                // do some analysis
+                switch (i.resourceType)
+                {
+                    case ResourceType_Processor:     // 3
+                        /*  <rasd:Caption>1 virtual CPU</rasd:Caption>
+                            <rasd:Description>Number of virtual CPUs</rasd:Description>
+                            <rasd:ElementName>virtual CPU</rasd:ElementName>
+                            <rasd:InstanceID>1</rasd:InstanceID>
+                            <rasd:ResourceType>3</rasd:ResourceType>
+                            <rasd:VirtualQuantity>1</rasd:VirtualQuantity>*/
+                        if (i.ullVirtualQuantity < UINT16_MAX)
+                            vsys.cCPUs = (uint16_t)i.ullVirtualQuantity;
+                        else
+                            throw OVFLogicError(N_("Error reading \"%s\": CPU count %RI64 is larger than %d, line %d"),
+                                                m_strPath.c_str(),
+                                                i.ullVirtualQuantity,
+                                                UINT16_MAX,
+                                                i.m_iLineNumber);
+                        break;
+
+                    case ResourceType_Memory:        // 4
+                        /* It's always stored in bytes in VSD according to the old internal agreement within the team */
+                        if (    i.strAllocationUnits == "MegaBytes"           // found in OVF created by OVF toolkit
+                             || i.strAllocationUnits == "MB"                  // found in MS docs
+                             || i.strAllocationUnits == "byte * 2^20"         // suggested by OVF spec DSP0243 page 21
+                           )
+                            vsys.ullMemorySize = i.ullVirtualQuantity * _1M;
+                        else if ( i.strAllocationUnits == "GigaBytes"
+                                  || i.strAllocationUnits == "GB"
+                                  || i.strAllocationUnits == "byte * 2^30"
+                           )
+                            vsys.ullMemorySize = i.ullVirtualQuantity * _1G;
+                        else
+                            throw OVFLogicError(N_("Error reading \"%s\": Invalid allocation unit \"%s\" specified with memory size item, line %d"),
+                                                m_strPath.c_str(),
+                                                i.strAllocationUnits.c_str(),
+                                                i.m_iLineNumber);
+                        break;
+
+                    case ResourceType_IDEController:          // 5
+                    {
+                        /*  <Item>
+                                <rasd:Caption>ideController0</rasd:Caption>
+                                <rasd:Description>IDE Controller</rasd:Description>
+                                <rasd:InstanceId>5</rasd:InstanceId>
+                                <rasd:ResourceType>5</rasd:ResourceType>
+                                <rasd:Address>0</rasd:Address>
+                                <rasd:BusNumber>0</rasd:BusNumber>
+                            </Item> */
+                        HardDiskController hdc;
+                        hdc.system = HardDiskController::IDE;
+                        hdc.strIdController = i.strInstanceID;
+                        hdc.strControllerType = i.strResourceSubType;
+
+                        hdc.lAddress = i.lAddress;
+
+                        if (!pPrimaryIDEController)
+                            // this is the first IDE controller found: then mark it as "primary"
+                            hdc.fPrimary = true;
+                        else
+                        {
+                            // this is the second IDE controller found: If VMware exports two
+                            // IDE controllers, it seems that they are given an "Address" of 0
+                            // an 1, respectively, so assume address=0 means primary controller
+                            if (    pPrimaryIDEController->lAddress == 0
+                                 && hdc.lAddress == 1
+                               )
+                            {
+                                pPrimaryIDEController->fPrimary = true;
+                                hdc.fPrimary = false;
+                            }
+                            else if (    pPrimaryIDEController->lAddress == 1
+                                      && hdc.lAddress == 0
+                                    )
+                            {
+                                pPrimaryIDEController->fPrimary = false;
+                                hdc.fPrimary = false;
+                            }
+                            else
+                                // then we really can't tell, just hope for the best
+                                hdc.fPrimary = false;
+                        }
+
+                        vsys.mapControllers[i.strInstanceID] = hdc;
+                        if (!pPrimaryIDEController)
+                            pPrimaryIDEController = &vsys.mapControllers[i.strInstanceID];
+                        break;
+                    }
+
+                    case ResourceType_ParallelSCSIHBA:        // 6       SCSI controller
+                    {
+                        /*  <Item>
+                                <rasd:Caption>SCSI Controller 0 - LSI Logic</rasd:Caption>
+                                <rasd:Description>SCI Controller</rasd:Description>
+                                <rasd:ElementName>SCSI controller</rasd:ElementName>
+                                <rasd:InstanceID>4</rasd:InstanceID>
+                                <rasd:ResourceSubType>LsiLogic</rasd:ResourceSubType>
+                                <rasd:ResourceType>6</rasd:ResourceType>
+                            </Item> */
+                        HardDiskController hdc;
+                        hdc.system = HardDiskController::SCSI;
+                        hdc.strIdController = i.strInstanceID;
+                        hdc.strControllerType = i.strResourceSubType;
+
+                        vsys.mapControllers[i.strInstanceID] = hdc;
+                        break;
+                    }
+
+                    case ResourceType_EthernetAdapter: // 10
+                    {
+                        /*  <Item>
+                            <rasd:Caption>Ethernet adapter on 'Bridged'</rasd:Caption>
+                            <rasd:AutomaticAllocation>true</rasd:AutomaticAllocation>
+                            <rasd:Connection>Bridged</rasd:Connection>
+                            <rasd:InstanceID>6</rasd:InstanceID>
+                            <rasd:ResourceType>10</rasd:ResourceType>
+                            <rasd:ResourceSubType>E1000</rasd:ResourceSubType>
+                            </Item>
+
+                            OVF spec DSP 0243 page 21:
+                           "For an Ethernet adapter, this specifies the abstract network connection name
+                            for the virtual machine. All Ethernet adapters that specify the same abstract
+                            network connection name within an OVF package shall be deployed on the same
+                            network. The abstract network connection name shall be listed in the NetworkSection
+                            at the outermost envelope level." */
+
+                        // only store the name
+                        EthernetAdapter ea;
+                        ea.strAdapterType = i.strResourceSubType;
+                        ea.strNetworkName = i.strConnection;
+                        vsys.llEthernetAdapters.push_back(ea);
+                        break;
+                    }
+
+                    case ResourceType_FloppyDrive: // 14
+                        vsys.fHasFloppyDrive = true;           // we have no additional information
+                        break;
+
+                    case ResourceType_CDDrive:       // 15
+                        /*  <Item ovf:required="false">
+                                <rasd:Caption>cdrom1</rasd:Caption>
+                                <rasd:InstanceId>7</rasd:InstanceId>
+                                <rasd:ResourceType>15</rasd:ResourceType>
+                                <rasd:AutomaticAllocation>true</rasd:AutomaticAllocation>
+                                <rasd:Parent>5</rasd:Parent>
+                                <rasd:AddressOnParent>0</rasd:AddressOnParent>
+                            </Item> */
+                            // I tried to see what happens if I set an ISO for the CD-ROM in VMware Workstation,
+                            // but then the ovftool dies with "Device backing not supported". So I guess if
+                            // VMware can't export ISOs, then we don't need to be able to import them right now.
+                        vsys.fHasCdromDrive = true;           // we have no additional information
+                        break;
+
+                    case ResourceType_HardDisk: // 17
+                        // handled separately in second loop below
+                        break;
+
+                    case ResourceType_OtherStorageDevice:        // 20       SATA/Virtio-SCSI/NVMe controller
+                    {
+                        /* <Item>
+                            <rasd:Description>SATA Controller</rasd:Description>
+                            <rasd:Caption>sataController0</rasd:Caption>
+                            <rasd:InstanceID>4</rasd:InstanceID>
+                            <rasd:ResourceType>20</rasd:ResourceType>
+                            <rasd:ResourceSubType>AHCI</rasd:ResourceSubType>
+                            <rasd:Address>0</rasd:Address>
+                            <rasd:BusNumber>0</rasd:BusNumber>
+                        </Item> */
+                        if (   i.strResourceSubType.compare("AHCI", RTCString::CaseInsensitive) == 0
+                            || i.strResourceSubType.compare("vmware.sata.ahci", RTCString::CaseInsensitive) == 0)
+                        {
+                            HardDiskController hdc;
+                            hdc.system = HardDiskController::SATA;
+                            hdc.strIdController = i.strInstanceID;
+                            hdc.strControllerType = i.strResourceSubType;
+
+                            vsys.mapControllers[i.strInstanceID] = hdc;
+                        }
+                        else if (   i.strResourceSubType.compare("VirtioSCSI", RTCString::CaseInsensitive) == 0
+                                 || i.strResourceSubType.compare("virtio-scsi", RTCString::CaseInsensitive) == 0 )
+                        {
+                            HardDiskController hdc;
+                            hdc.system = HardDiskController::VIRTIOSCSI;
+                            hdc.strIdController = i.strInstanceID;
+                            //<rasd:ResourceSubType>VirtioSCSI</rasd:ResourceSubType>
+                            hdc.strControllerType = i.strResourceSubType;
+                            vsys.mapControllers[i.strInstanceID] = hdc;
+                        }
+                        else if (   i.strResourceSubType.compare("NVMe", RTCString::CaseInsensitive) == 0
+                                 || i.strResourceSubType.compare("vmware.nvme.controller", RTCString::CaseInsensitive) == 0 )
+                        {
+                            HardDiskController hdc;
+                            hdc.system = HardDiskController::NVMe;
+                            hdc.strIdController = i.strInstanceID;
+                            //<rasd:ResourceSubType>NVMe</rasd:ResourceSubType>
+                            hdc.strControllerType = i.strResourceSubType;
+                            vsys.mapControllers[i.strInstanceID] = hdc;
+                        }
+                        else
+                            throw OVFLogicError(N_("Error reading \"%s\": Host resource of type \"Other Storage Device (%d)\" is supported with SATA AHCI or Virtio-SCSI or NVMe controllers only, line %d (subtype:%s)"),
+                                                m_strPath.c_str(),
+                                                ResourceType_OtherStorageDevice,
+                                                i.m_iLineNumber, i.strResourceSubType.c_str() );
+                        break;
+                    }
+
+                    case ResourceType_USBController: // 23
+                        /*  <Item ovf:required="false">
+                                <rasd:Caption>usb</rasd:Caption>
+                                <rasd:Description>USB Controller</rasd:Description>
+                                <rasd:InstanceId>3</rasd:InstanceId>
+                                <rasd:ResourceType>23</rasd:ResourceType>
+                                <rasd:Address>0</rasd:Address>
+                                <rasd:BusNumber>0</rasd:BusNumber>
+                            </Item> */
+                        vsys.fHasUsbController = true;           // we have no additional information
+                        break;
+
+                    case ResourceType_SoundCard: // 35
+                        /*  <Item ovf:required="false">
+                                <rasd:Caption>sound</rasd:Caption>
+                                <rasd:Description>Sound Card</rasd:Description>
+                                <rasd:InstanceId>10</rasd:InstanceId>
+                                <rasd:ResourceType>35</rasd:ResourceType>
+                                <rasd:ResourceSubType>ensoniq1371</rasd:ResourceSubType>
+                                <rasd:AutomaticAllocation>false</rasd:AutomaticAllocation>
+                                <rasd:AddressOnParent>3</rasd:AddressOnParent>
+                            </Item> */
+                        vsys.strSoundCardType = i.strResourceSubType;
+                        break;
+
+                    default:
+                    {
+                        /* If this unknown resource type isn't required, we simply skip it. */
+                        if (i.fResourceRequired)
+                        {
+                            throw OVFLogicError(N_("Error reading \"%s\": Unknown resource type %d in hardware item, line %d"),
+                                                m_strPath.c_str(),
+                                                i.resourceType,
+                                                i.m_iLineNumber);
+                        }
+                    }
+                } // end switch
+            }
+
+            // now run through the items for a second time, but handle only
+            // hard disk images; otherwise the code would fail if a hard
+            // disk image appears in the OVF before its hard disk controller
+            for (itH = vsys.vecHardwareItems.begin(); itH != vsys.vecHardwareItems.end(); ++itH)
+            {
+                const VirtualHardwareItem &i = **itH;
+
+                // do some analysis
+                switch (i.resourceType)
+                {
+                    case ResourceType_CDDrive: // 15
+                        /*  <Item ovf:required="false">
+                                <rasd:Caption>cdrom1</rasd:Caption>
+                                <rasd:InstanceId>7</rasd:InstanceId>
+                                <rasd:ResourceType>15</rasd:ResourceType>
+                                <rasd:AutomaticAllocation>true</rasd:AutomaticAllocation>
+                                <rasd:Parent>5</rasd:Parent>
+                                <rasd:AddressOnParent>0</rasd:AddressOnParent>
+                            </Item> */
+                    case ResourceType_HardDisk: // 17
+                    {
+                        /*  <Item>
+                                <rasd:Caption>Harddisk 1</rasd:Caption>
+                                <rasd:Description>HD</rasd:Description>
+                                <rasd:ElementName>Hard Disk</rasd:ElementName>
+                                <rasd:HostResource>ovf://disk/lamp</rasd:HostResource>
+                                <rasd:InstanceID>5</rasd:InstanceID>
+                                <rasd:Parent>4</rasd:Parent>
+                                <rasd:ResourceType>17</rasd:ResourceType>
+                            </Item> */
+
+                        // look up the hard disk controller element whose InstanceID equals our Parent;
+                        // this is how the connection is specified in OVF
+                        ControllersMap::const_iterator it = vsys.mapControllers.find(i.strParent);
+                        if (it == vsys.mapControllers.end())
+                            throw OVFLogicError(N_("Error reading \"%s\": Disk item with instance ID \"%s\" specifies invalid parent \"%s\", line %d"),
+                                                m_strPath.c_str(),
+                                                i.strInstanceID.c_str(),
+                                                i.strParent.c_str(),
+                                                i.m_iLineNumber);
+
+                        VirtualDisk vd;
+                        vd.strIdController = i.strParent;
+                        i.strAddressOnParent.toInt(vd.ulAddressOnParent);
+                        // ovf://disk/lamp
+                        // 123456789012345
+                        if (i.strHostResource.startsWith("ovf://disk/"))
+                            vd.strDiskId = i.strHostResource.substr(11);
+                        else if (i.strHostResource.startsWith("ovf:/disk/"))
+                            vd.strDiskId = i.strHostResource.substr(10);
+                        else if (i.strHostResource.startsWith("/disk/"))
+                            vd.strDiskId = i.strHostResource.substr(6);
+
+                        //the error may be missed for CD, because CD can be empty
+                        if ((vd.strDiskId.isEmpty() || (m_mapDisks.find(vd.strDiskId) == m_mapDisks.end()))
+                             && i.resourceType == ResourceType_HardDisk)
+                          throw OVFLogicError(N_("Error reading \"%s\": Disk item with instance ID \"%s\" specifies invalid host resource \"%s\", line %d"),
+                                              m_strPath.c_str(),
+                                              i.strInstanceID.c_str(),
+                                              i.strHostResource.c_str(),
+                                              i.m_iLineNumber);
+
+                        vsys.mapVirtualDisks[vd.strDiskId] = vd;
+                        break;
+                    }
+                    default:
+                        break;
+                }
+            }
+        }
+        else if (    !strcmp(pcszElemName, "OperatingSystemSection")
+                  || !strcmp(pcszTypeAttr, "ovf:OperatingSystemSection_Type")
+                )
+        {
+            uint64_t cimos64;
+            if (!(pelmThis->getAttributeValue("id", cimos64)))
+                throw OVFLogicError(N_("Error reading \"%s\": missing or invalid 'ovf:id' attribute in operating system section element, line %d"),
+                                    m_strPath.c_str(),
+                                    pelmThis->getLineNumber());
+
+            vsys.cimos = (CIMOSType_T)cimos64;
+            const xml::ElementNode *pelmCIMOSDescription;
+            if ((pelmCIMOSDescription = pelmThis->findChildElement("Description")))
+                vsys.strCimosDesc = pelmCIMOSDescription->getValueN(RT_XML_CONTENT_SMALL);
+
+            const xml::ElementNode *pelmVBoxOSType;
+            if ((pelmVBoxOSType = pelmThis->findChildElementNS("vbox",            // namespace
+                                                               "OSType")))        // element name
+                vsys.strTypeVBox = pelmVBoxOSType->getValueN(RT_XML_CONTENT_SMALL);
+        }
+        else if (    (!strcmp(pcszElemName, "AnnotationSection"))
+                  || (!strcmp(pcszTypeAttr, "ovf:AnnotationSection_Type"))
+                )
+        {
+            const xml::ElementNode *pelmAnnotation;
+            if ((pelmAnnotation = pelmThis->findChildElement("Annotation")))
+                vsys.strDescription = pelmAnnotation->getValueN(RT_XML_CONTENT_SMALL);
+        }
+    }
+}
+
+void VirtualHardwareItem::fillItem(const xml::ElementNode *item)
+{
+    xml::NodesLoop loopItemChildren(*item);// all child elements
+    const xml::ElementNode *pelmItemChild;
+    while ((pelmItemChild = loopItemChildren.forAllNodes()))
+    {
+        const char *pcszItemChildName = pelmItemChild->getName();
+        if (!strcmp(pcszItemChildName, "Description"))
+            strDescription = pelmItemChild->getValueN(RT_XML_CONTENT_SMALL);
+        else if (!strcmp(pcszItemChildName, "Caption"))
+            strCaption = pelmItemChild->getValueN(RT_XML_CONTENT_SMALL);
+        else if (!strcmp(pcszItemChildName, "ElementName"))
+            strElementName = pelmItemChild->getValueN(RT_XML_CONTENT_SMALL);
+        else if (   !strcmp(pcszItemChildName, "InstanceID")
+                 || !strcmp(pcszItemChildName, "InstanceId") )
+            strInstanceID = pelmItemChild->getValueN(RT_XML_CONTENT_SMALL);
+        else if (!strcmp(pcszItemChildName, "HostResource"))
+            strHostResource = pelmItemChild->getValueN(RT_XML_CONTENT_SMALL);
+        else if (!strcmp(pcszItemChildName, "ResourceType"))
+        {
+            uint32_t ulType;
+            pelmItemChild->copyValue(ulType);
+            if (ulType > 0xffff)
+                ulType = 0xffff;
+            resourceType = (ResourceType_T)ulType;
+            fResourceRequired = true;
+            const char *pcszAttValue;
+            if (item->getAttributeValueN("required", pcszAttValue, RT_XML_ATTR_TINY))
+            {
+                if (!strcmp(pcszAttValue, "false"))
+                    fResourceRequired = false;
+            }
+        }
+        else if (!strcmp(pcszItemChildName, "OtherResourceType"))
+            strOtherResourceType = pelmItemChild->getValueN(RT_XML_CONTENT_SMALL);
+        else if (!strcmp(pcszItemChildName, "ResourceSubType"))
+            strResourceSubType = pelmItemChild->getValueN(RT_XML_CONTENT_SMALL);
+        else if (!strcmp(pcszItemChildName, "AutomaticAllocation"))
+            fAutomaticAllocation = (!strcmp(pelmItemChild->getValueN(RT_XML_CONTENT_SMALL), "true")) ? true : false;
+        else if (!strcmp(pcszItemChildName, "AutomaticDeallocation"))
+            fAutomaticDeallocation = (!strcmp(pelmItemChild->getValueN(RT_XML_CONTENT_SMALL), "true")) ? true : false;
+        else if (!strcmp(pcszItemChildName, "Parent"))
+            strParent = pelmItemChild->getValueN(RT_XML_CONTENT_SMALL);
+        else if (!strcmp(pcszItemChildName, "Connection"))
+            strConnection = pelmItemChild->getValueN(RT_XML_CONTENT_SMALL);
+        else if (!strcmp(pcszItemChildName, "Address"))
+        {
+            strAddress = pelmItemChild->getValueN(RT_XML_CONTENT_SMALL);
+            pelmItemChild->copyValue(lAddress);
+        }
+        else if (!strcmp(pcszItemChildName, "AddressOnParent"))
+            strAddressOnParent = pelmItemChild->getValueN(RT_XML_CONTENT_SMALL);
+        else if (!strcmp(pcszItemChildName, "AllocationUnits"))
+            strAllocationUnits = pelmItemChild->getValueN(RT_XML_CONTENT_SMALL);
+        else if (!strcmp(pcszItemChildName, "VirtualQuantity"))
+            pelmItemChild->copyValue(ullVirtualQuantity);
+        else if (!strcmp(pcszItemChildName, "Reservation"))
+            pelmItemChild->copyValue(ullReservation);
+        else if (!strcmp(pcszItemChildName, "Limit"))
+            pelmItemChild->copyValue(ullLimit);
+        else if (!strcmp(pcszItemChildName, "Weight"))
+            pelmItemChild->copyValue(ullWeight);
+        else if (!strcmp(pcszItemChildName, "ConsumerVisibility"))
+            strConsumerVisibility = pelmItemChild->getValueN(RT_XML_CONTENT_SMALL);
+        else if (!strcmp(pcszItemChildName, "MappingBehavior"))
+            strMappingBehavior = pelmItemChild->getValueN(RT_XML_CONTENT_SMALL);
+        else if (!strcmp(pcszItemChildName, "PoolID"))
+            strPoolID = pelmItemChild->getValueN(RT_XML_CONTENT_SMALL);
+        else if (!strcmp(pcszItemChildName, "BusNumber"))
+            pelmItemChild->copyValue(ulBusNumber);
+//      else if (pelmItemChild->getPrefix() == NULL
+//               || strcmp(pelmItemChild->getPrefix(), "vmw"))
+//          throw OVFLogicError(N_("Unknown element '%s' under Item element, line %d"),
+//                              pcszItemChildName,
+//                              m_iLineNumber);
+    }
+}
+
+void VirtualHardwareItem::_checkConsistencyAndCompliance() RT_THROW(OVFLogicError)
+{
+    RTCString name = getItemName();
+    if (resourceType == 0)
+        throw OVFLogicError(N_("Empty element ResourceType under %s element, line %d. see DMTF Schema Documentation %s"),
+                            name.c_str(), m_iLineNumber, DTMF_SPECS_URI);
+
+    /* Don't be too uptight about the strInstanceID value.  There are OVAs out
+       there which have InstanceID="%iid%" for memory for instance, which is
+       no good reason for not being able to process them.  bugref:8997 */
+    if (strInstanceID.isEmpty())
+    {
+        if (   resourceType == ResourceType_IDEController
+            || resourceType == ResourceType_OtherStorageDevice
+            || resourceType == ResourceType_ParallelSCSIHBA
+            || resourceType == ResourceType_iSCSIHBA //??
+            || resourceType == ResourceType_IBHCA )  //??
+            throw OVFLogicError(N_("Element InstanceID is absent under %s element, line %d. see DMTF Schema Documentation %s"),
+                                name.c_str(), m_iLineNumber, DTMF_SPECS_URI);
+        else
+            LogRel(("OVFREADER: Warning: Ignoring missing or invalid InstanceID under element %s, line %u\n",
+                    name.c_str(), m_iLineNumber));
+    }
+}
+
+void StorageItem::fillItem(const xml::ElementNode *item)
+{
+    VirtualHardwareItem::fillItem(item);
+
+    xml::NodesLoop loopItemChildren(*item);// all child elements
+    const xml::ElementNode *pelmItemChild;
+    while ((pelmItemChild = loopItemChildren.forAllNodes()))
+    {
+        const char *pcszItemChildName = pelmItemChild->getName();
+        if (!strcmp(pcszItemChildName, "HostExtentName"))
+            strHostExtentName = pelmItemChild->getValueN(RT_XML_CONTENT_SMALL);
+        else if (!strcmp(pcszItemChildName, "OtherHostExtentNameFormat"))
+            strOtherHostExtentNameFormat = pelmItemChild->getValueN(RT_XML_CONTENT_SMALL);
+        else if (!strcmp(pcszItemChildName, "OtherHostExtentNameNamespace"))
+            strOtherHostExtentNameNamespace = pelmItemChild->getValueN(RT_XML_CONTENT_SMALL);
+        else if (!strcmp(pcszItemChildName, "VirtualQuantityUnits"))
+            strVirtualQuantityUnits = pelmItemChild->getValueN(RT_XML_CONTENT_SMALL);
+        else if (!strcmp(pcszItemChildName, "Access"))
+        {
+            uint32_t temp;
+            pelmItemChild->copyValue(temp);
+            accessType = (StorageAccessType_T)temp;
+        }
+        else if (!strcmp(pcszItemChildName, "HostExtentNameFormat"))
+        {
+        }
+        else if (!strcmp(pcszItemChildName, "HostExtentNameNamespace"))
+        {
+        }
+        else if (!strcmp(pcszItemChildName, "HostExtentStartingAddress"))
+        {
+        }
+        else if (!strcmp(pcszItemChildName, "HostResourceBlockSize"))
+        {
+            int64_t temp;
+            pelmItemChild->copyValue(temp);
+            hostResourceBlockSize = temp;
+        }
+        else if (!strcmp(pcszItemChildName, "Limit"))
+        {
+            int64_t temp;
+            pelmItemChild->copyValue(temp);
+            limit = temp;
+        }
+        else if (!strcmp(pcszItemChildName, "Reservation"))
+        {
+            int64_t temp;
+            pelmItemChild->copyValue(temp);
+            reservation = temp;
+        }
+        else if (!strcmp(pcszItemChildName, "VirtualQuantity"))
+        {
+            int64_t temp;
+            pelmItemChild->copyValue(temp);
+            virtualQuantity = temp;
+        }
+        else if (!strcmp(pcszItemChildName, "VirtualResourceBlockSize"))
+        {
+            int64_t temp;
+            pelmItemChild->copyValue(temp);
+            virtualResourceBlockSize = temp;
+        }
+    }
+}
+
+
+void StorageItem::_checkConsistencyAndCompliance() RT_THROW(OVFLogicError)
+{
+    VirtualHardwareItem::_checkConsistencyAndCompliance();
+
+    RTCString name = getItemName();
+
+    if (accessType == StorageAccessType_Unknown)
+    {
+        //throw OVFLogicError(N_("Access type is unknown under %s element, line %d"),
+        //                    name.c_str(), m_iLineNumber);
+    }
+
+    if (hostResourceBlockSize <= 0 && reservation > 0)
+    {
+        throw OVFLogicError(N_("Element HostResourceBlockSize is absent under %s element, line %d. "
+                               "see DMTF Schema Documentation %s"),
+                            name.c_str(), m_iLineNumber, DTMF_SPECS_URI);
+    }
+
+    if (virtualResourceBlockSize <= 0 && virtualQuantity > 0)
+    {
+        throw OVFLogicError(N_("Element VirtualResourceBlockSize is absent under %s element, line %d. "
+                               "see DMTF Schema Documentation %s"),
+                            name.c_str(), m_iLineNumber, DTMF_SPECS_URI);
+    }
+
+    if (virtualQuantity > 0 && strVirtualQuantityUnits.isEmpty())
+    {
+        throw OVFLogicError(N_("Element VirtualQuantityUnits is absent under %s element, line %d. "
+                               "see DMTF Schema Documentation %s"),
+                            name.c_str(), m_iLineNumber, DTMF_SPECS_URI);
+    }
+
+    if (virtualResourceBlockSize <= 1 &&
+        strVirtualQuantityUnits.compare(RTCString("count"), RTCString::CaseInsensitive) == 0
+       )
+    {
+        throw OVFLogicError(N_("Element VirtualQuantityUnits is set to \"count\" "
+                               "while VirtualResourceBlockSize is set to 1. "
+                               "under %s element, line %d. "
+                               "It's needed to change on \"byte\". "
+                               "see DMTF Schema Documentation %s"),
+                            name.c_str(), m_iLineNumber, DTMF_SPECS_URI);
+    }
+}
+
+void EthernetPortItem::fillItem(const xml::ElementNode *item)
+{
+    VirtualHardwareItem::fillItem(item);
+
+    xml::NodesLoop loopItemChildren(*item);// all child elements
+    const xml::ElementNode *pelmItemChild;
+    while ((pelmItemChild = loopItemChildren.forAllNodes()))
+    {
+    }
+}
+
+void EthernetPortItem::_checkConsistencyAndCompliance() RT_THROW(OVFLogicError)
+{
+    VirtualHardwareItem::_checkConsistencyAndCompliance();
+}
+
+////////////////////////////////////////////////////////////////////////////////
+//
+// Errors
+//
+////////////////////////////////////////////////////////////////////////////////
+
+OVFLogicError::OVFLogicError(const char *aFormat, ...)
+{
+    char *pszNewMsg;
+    va_list args;
+    va_start(args, aFormat);
+    RTStrAPrintfV(&pszNewMsg, aFormat, args);
+    setWhat(pszNewMsg);
+    RTStrFree(pszNewMsg);
+    va_end(args);
+}
diff --git a/src/VBox/Main/xml/samples/VirtualBox-global.xml b/src/VBox/Main/xml/samples/VirtualBox-global.xml
new file mode 100644
index 00000000..139a47ce
--- /dev/null
+++ b/src/VBox/Main/xml/samples/VirtualBox-global.xml
@@ -0,0 +1,62 @@
+<?xml version="1.0" encoding="UTF-8" standalone="no" ?>
+<!-- Oracle VM VirtualBox Sample Global Configuration -->
+<!--
+ *  :tabSize=2:indentSize=2:noTabs=true:
+ *  :folding=explicit:collapseFolds=1:
+-->
+
+<VirtualBox
+  xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"
+  xsi:schemaLocation="http://www.innotek.de/VirtualBox-settings ../VirtualBox-settings-windows.xsd"
+  xmlns="http://www.innotek.de/VirtualBox-settings"
+  version="1.2-windows"
+>
+
+  <Global>
+    <ExtraData>
+      <ExtraDataItem name="GUI/Input/HostKey" value="165"/>
+      <ExtraDataItem name="GUI/Input/AutoCapture" value="true"/>
+      <ExtraDataItem name="GUI/SuppressMessages" value="remindAboutAutoCapture,remindAboutMouseIntegrationOn"/>
+    </ExtraData>
+    <MachineRegistry>
+      <MachineEntry src="Machines\{1a4d3cff-e693-4ae5-afaf-a1ccc6882183}.xml" uuid="{1a4d3cff-e693-4ae5-afaf-a1ccc6882183}"/>
+      <MachineEntry src="Machines\{aa08aecf-e67d-46b9-a325-948691660689}.xml" uuid="{aa08aecf-e67d-46b9-a325-948691660689}"/>
+      <MachineEntry src="Machines/%7B81ae80b4-2507-4fe8-bed8-33f14920d301%7D.xml" uuid="{81ae80b4-2507-4fe8-bed8-33f14920d301}"/>
+    </MachineRegistry>
+    <DiskRegistry>
+      <HardDisks>
+        <HardDisk uuid="{23dbf22e-9f27-49da-bdae-f4c43f968057}" type="normal">
+          <VirtualDiskImage filePath="E:/develop/innotek/images/nt4ger.vdi"/>
+          <DiffHardDisk uuid="{23dbf22e-9f27-49da-bdae-f4c43f968057}">
+            <VirtualDiskImage filePath="E:/develop/innotek/images/diff1.vdi"/>
+          </DiffHardDisk>
+          <DiffHardDisk uuid="{23dbf22e-9f27-49da-bdae-f4c43f968057}">
+            <VirtualDiskImage filePath="E:/develop/innotek/images/diff2.vdi"/>
+            <DiffHardDisk uuid="{23dbf22e-9f27-49da-bdae-f4c43f968057}">
+              <VirtualDiskImage filePath="E:/develop/innotek/images/diff2.vdi"/>
+            </DiffHardDisk>
+          </DiffHardDisk>
+        </HardDisk>
+        <HardDisk uuid="{23dbf22e-9f27-49da-bdae-f4c43f968058}" type="immutable">
+          <ISCSIHardDisk server="abc.com" target="drive"/>
+        </HardDisk>
+        <HardDisk uuid="{23dbf22e-9f27-49da-bdae-f4c43f968059}" type="writethrough">
+          <PhysicalVolume path="D:"/>
+        </HardDisk>
+      </HardDisks>
+      <DVDImages>
+        <Image src="e:/Develop/innotek/images/fdbootcd.iso" uuid="{8c307b77-f331-45fd-b8b4-cbc5281bf0FF}"/>
+      </DVDImages>
+      <FloppyImages>
+      </FloppyImages>
+    </DiskRegistry>
+    <SystemProperties defaultVDIFolder="somefolder"/>
+    <USBDeviceFilters>
+      <DeviceFilter name="Test1" active="false" action="Ignore"/>
+      <DeviceFilter name="Test2" active="false" vendorid="MegaCorpLTD" action="Ignore"/>
+    </USBDeviceFilters>
+  </Global>
+
+</VirtualBox>
+
+
diff --git a/src/VBox/Main/xml/samples/VirtualBox-machine-linux.xml b/src/VBox/Main/xml/samples/VirtualBox-machine-linux.xml
new file mode 100644
index 00000000..8b67af38
--- /dev/null
+++ b/src/VBox/Main/xml/samples/VirtualBox-machine-linux.xml
@@ -0,0 +1,65 @@
+<?xml version="1.0" encoding="UTF-8" standalone="no" ?>
+<!-- Oracle VM VirtualBox Sample Machine Configuration (for a linux host) -->
+<!--
+ *  :tabSize=2:indentSize=2:noTabs=true:
+ *  :folding=explicit:collapseFolds=1:
+-->
+
+<VirtualBox
+  xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"
+  xsi:schemaLocation="http://www.innotek.de/VirtualBox-settings ../VirtualBox-settings-linux.xsd"
+  xmlns="http://www.innotek.de/VirtualBox-settings"
+  version="1.2-linux"
+>
+
+  <Machine
+    name="dos" OSType="dos" uuid="{1a4d3cff-e693-4ae5-afaf-a1ccc6882183}"
+    stateFile="aaa.sav"
+  >
+
+    <HardDiskAttachments>
+      <HardDiskAttachment hardDisk="{508b474f-62ce-4872-9a42-3af09037a277}"
+                          bus="ide0" device="master"/>
+    </HardDiskAttachments>
+
+    <Hardware>
+      <Memory RAMSize="128"/>
+      <Boot>
+          <Order device="None" position="4"/>
+          <Order device="None" position="2"/>
+          <Order device="HardDisk" position="1"/>
+          <Order device="Floppy" position="3"/>
+      </Boot>
+      <Display VRAMSize="4"/>
+      <RemoteDisplay enabled="false"/>
+      <BIOS>
+        <ACPI enabled="false"/>
+        <Logo displayTime="0" fadeIn="true" fadeOut="true"/>
+      </BIOS>
+      <DVDDrive>
+          <Image uuid="{00000000-0000-0000-0100-000000000000}"/>
+      </DVDDrive>
+      <FloppyDrive>
+          <HostDrive src="aaa"/>
+      </FloppyDrive>
+      <USBController enabled="false"/>
+      <Network>
+        <Adapter slot="0" enabled="true" cable="true" MACAddress="08002751DD5E">
+          <NAT/>
+        </Adapter>
+        <Adapter slot="1" enabled="true" cable="false" MACAddress="08002751DD5E">
+          <HostInterface/>
+        </Adapter>
+        <Adapter slot="2" enabled="true" cable="false" MACAddress="08002751DD5E"/>
+        <Adapter slot="3" enabled="true" cable="false" MACAddress="08002751DD5E"/>
+      </Network>
+      <AudioAdapter driver="alsa" enabled="true"/>
+      <SharedFolders>
+          <SharedFolder name="aaa" hostPath="/bbb/ccc"/>
+          <SharedFolder name="aaab" hostPath="/bbb/ccc"/>
+      </SharedFolders>
+    </Hardware>
+
+  </Machine>
+
+</VirtualBox>
diff --git a/src/VBox/Main/xml/samples/VirtualBox-machine-windows.xml b/src/VBox/Main/xml/samples/VirtualBox-machine-windows.xml
new file mode 100644
index 00000000..729a9357
--- /dev/null
+++ b/src/VBox/Main/xml/samples/VirtualBox-machine-windows.xml
@@ -0,0 +1,203 @@
+<?xml version="1.0" encoding="UTF-8" standalone="no" ?>
+<!-- Oracle VM VirtualBox Sample Machine Configuration (for a win32 host) -->
+<!--
+ *  :tabSize=2:indentSize=2:noTabs=true:
+ *  :folding=explicit:collapseFolds=1:
+-->
+
+<VirtualBox
+  xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"
+  xsi:schemaLocation="http://www.innotek.de/VirtualBox-settings ../VirtualBox-settings-windows.xsd"
+  xmlns="http://www.innotek.de/VirtualBox-settings"
+  version="1.2-windows"
+>
+
+  <Machine
+    name="dos" OSType="dos" uuid="{00000000-0000-0000-0100-000000000000}"
+    currentSnapshot="{00000000-0000-0000-0111-000000000000}"
+    snapshotFolder="."
+    lastStateChange="2005-01-01T10:22:22Z"
+    aborted="true"
+  >
+    <Description>
+        Something is here.
+    </Description>
+    <Hardware>
+      <Memory RAMSize="128"/>
+      <Boot>
+          <Order device="None" position="1"/>
+          <Order device="HardDisk" position="2"/>
+      </Boot>
+      <Display VRAMSize="4"/>
+      <RemoteDisplay enabled="false"/>
+      <BIOS>
+        <ACPI enabled="false"/>
+        <Logo displayTime="0" fadeIn="true" fadeOut="true"/>
+      </BIOS>
+      <DVDDrive>
+          <Image uuid="{00000000-0000-0000-0100-000000000000}"/>
+      </DVDDrive>
+      <FloppyDrive>
+          <HostDrive src="aaa"/>
+      </FloppyDrive>
+      <USBController enabled="false">
+        <DeviceFilter name="Test1" active="false"/>
+      </USBController>
+      <Network>
+        <Adapter slot="0" enabled="false" cable="false" MACAddress="08002751DD5E"/>
+        <Adapter slot="3" enabled="false" cable="false" MACAddress="08002751DD5E">
+          <NAT/>
+        </Adapter>
+        <Adapter slot="2" enabled="false" cable="false" MACAddress="08002751DD5E">
+          <HostInterface name="Home LAN"/>
+        </Adapter>
+      </Network>
+      <AudioAdapter driver="winmm" enabled="true"/>
+    </Hardware>
+
+    <HardDiskAttachments>
+      <HardDiskAttachment hardDisk="{508b474f-62ce-4872-9a42-3af09037a277}"
+                          bus="ide0" device="master"/>
+    </HardDiskAttachments>
+
+    <ExtraData>
+      <ExtraDataItem name="GUI/LastCloseAction" value="powerOff"/>
+    </ExtraData>
+
+    <Snapshot
+      name="Snapshot 1" uuid="{00000000-0000-0000-0111-000000000000}"
+      timeStamp="2006-01-01T00:00:00Z"
+    >
+      <Hardware>
+        <Memory RAMSize="128"/>
+        <Boot>
+            <Order device="None" position="1"/>
+            <Order device="HardDisk" position="2"/>
+        </Boot>
+        <Display VRAMSize="4"/>
+        <RemoteDisplay enabled="false"/>
+        <BIOS>
+          <ACPI enabled="false"/>
+          <Logo displayTime="0" fadeIn="true" fadeOut="true"/>
+        </BIOS>
+        <DVDDrive>
+            <Image uuid="{00000000-0000-0000-0100-000000000000}"/>
+        </DVDDrive>
+        <FloppyDrive>
+            <HostDrive src="aaa"/>
+        </FloppyDrive>
+        <USBController enabled="false">
+          <DeviceFilter name="Test1" active="false"/>
+        </USBController>
+        <Network>
+          <Adapter slot="0" enabled="false" cable="false" MACAddress="08002751DD5E"/>
+          <Adapter slot="3" enabled="false" cable="false" MACAddress="08002751DD5E">
+            <NAT/>
+          </Adapter>
+          <Adapter slot="2" enabled="false" cable="false" MACAddress="08002751DD5E">
+            <HostInterface name="Home LAN"/>
+          </Adapter>
+        </Network>
+        <AudioAdapter driver="winmm" enabled="true"/>
+        <Clipboard mode="Disabled"/>
+      </Hardware>
+      <HardDiskAttachments>
+        <HardDiskAttachment hardDisk="{508b474f-62ce-4872-9a42-3af09037a277}"
+                            bus="ide0" device="master"/>
+      </HardDiskAttachments>
+
+      <Snapshots>
+
+        <Snapshot
+          name="Snapshot 2" uuid="{00000000-0000-0000-0100-000000000000}"
+          timeStamp="2006-01-01T00:00:00Z"
+          stateFile="D:\aaa\bbb.sav"
+        >
+          <Description>ewfqwef</Description>
+          <Hardware>
+            <Memory RAMSize="128"/>
+            <Boot>
+                <Order device="None" position="1"/>
+                <Order device="HardDisk" position="2"/>
+            </Boot>
+            <Display VRAMSize="4"/>
+            <RemoteDisplay enabled="false"/>
+            <BIOS>
+              <ACPI enabled="false"/>
+              <Logo displayTime="0" fadeIn="true" fadeOut="true"/>
+            </BIOS>
+            <DVDDrive>
+                <Image uuid="{00000000-0000-0000-0100-000000000000}"/>
+            </DVDDrive>
+            <FloppyDrive>
+                <HostDrive src="aaa"/>
+            </FloppyDrive>
+            <USBController enabled="false">
+              <DeviceFilter name="Test1" active="false"/>
+            </USBController>
+            <Network>
+              <Adapter slot="0" enabled="false" cable="false" MACAddress="08002751DD5E"/>
+              <Adapter slot="3" enabled="false" cable="false" MACAddress="08002751DD5E">
+                <NAT/>
+              </Adapter>
+              <Adapter slot="2" enabled="false" cable="false" MACAddress="08002751DD5E">
+                <HostInterface name="Home LAN"/>
+              </Adapter>
+            </Network>
+            <AudioAdapter driver="winmm" enabled="true"/>
+          </Hardware>
+          <HardDiskAttachments>
+            <HardDiskAttachment hardDisk="{508b474f-62ce-4872-9a42-3af09037a277}"
+                                bus="ide0" device="master"/>
+          </HardDiskAttachments>
+          <Snapshots/>
+        </Snapshot>
+
+        <Snapshot
+          name="Snapshot 3" uuid="{00000000-0000-0000-0112-000000000000}"
+          timeStamp="2006-01-01T00:00:00Z"
+        >
+          <Hardware>
+            <Memory RAMSize="128"/>
+            <Boot>
+                <Order device="None" position="1"/>
+                <Order device="HardDisk" position="2"/>
+            </Boot>
+            <Display VRAMSize="4"/>
+            <RemoteDisplay enabled="false"/>
+            <BIOS>
+              <ACPI enabled="false"/>
+              <Logo displayTime="0" fadeIn="true" fadeOut="true"/>
+            </BIOS>
+            <DVDDrive>
+                <Image uuid="{00000000-0000-0000-0100-000000000000}"/>
+            </DVDDrive>
+            <FloppyDrive>
+                <HostDrive src="aaa"/>
+            </FloppyDrive>
+            <USBController enabled="false">
+              <DeviceFilter name="Test1" active="false"/>
+            </USBController>
+            <Network>
+              <Adapter slot="0" enabled="false" cable="false" MACAddress="08002751DD5E"/>
+              <Adapter slot="3" enabled="false" cable="false" MACAddress="08002751DD5E">
+                <NAT/>
+              </Adapter>
+              <Adapter slot="2" enabled="false" cable="false" MACAddress="08002751DD5E">
+                <HostInterface name="Home LAN"/>
+              </Adapter>
+            </Network>
+            <AudioAdapter driver="winmm" enabled="true"/>
+          </Hardware>
+          <HardDiskAttachments>
+            <HardDiskAttachment hardDisk="{508b474f-62ce-4872-9a42-3af09037a277}"
+                                bus="ide0" device="master"/>
+          </HardDiskAttachments>
+          <Snapshots/>
+        </Snapshot>
+
+      </Snapshots>
+    </Snapshot>
+  </Machine>
+
+</VirtualBox>