Adding upstream version 6.0.4-dfsg.upstream/6.0.4-dfsgupstream

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

9 files changed, 3657 insertions, 0 deletions

diff --git a/src/VBox/NetworkServices/DHCP/ClientDataInt.h b/src/VBox/NetworkServices/DHCP/ClientDataInt.h
new file mode 100644
index 00000000..74879523
--- /dev/null
+++ b/src/VBox/NetworkServices/DHCP/ClientDataInt.h
@@ -0,0 +1,70 @@
+/* $Id: ClientDataInt.h $ */
+/** @file
+ * Config.h
+ */
+
+/*
+ * Copyright (C) 2013-2019 Oracle Corporation
+ *
+ * This file is part of VirtualBox Open Source Edition (OSE), as
+ * available from http://www.virtualbox.org. This file is free software;
+ * you can redistribute it and/or modify it under the terms of the GNU
+ * General Public License (GPL) as published by the Free Software
+ * Foundation, in version 2 as it comes in the "COPYING" file of the
+ * VirtualBox OSE distribution. VirtualBox OSE is distributed in the
+ * hope that it will be useful, but WITHOUT ANY WARRANTY of any kind.
+ */
+
+#ifndef VBOX_INCLUDED_SRC_DHCP_ClientDataInt_h
+#define VBOX_INCLUDED_SRC_DHCP_ClientDataInt_h
+#ifndef RT_WITHOUT_PRAGMA_ONCE
+# pragma once
+#endif
+
+class ClientData
+{
+public:
+    ClientData()
+    {
+        m_address.u = 0;
+        m_network.u = 0;
+        fHasLease = false;
+        fHasClient = false;
+        fBinding = true;
+        u64TimestampBindingStarted = 0;
+        u64TimestampLeasingStarted = 0;
+        u32LeaseExpirationPeriod = 0;
+        u32BindExpirationPeriod = 0;
+        pCfg = NULL;
+
+    }
+    ~ClientData(){}
+
+    /* client information */
+    RTNETADDRIPV4 m_address;
+    RTNETADDRIPV4 m_network;
+    RTMAC m_mac;
+
+    bool fHasClient;
+
+    /* Lease part */
+    bool fHasLease;
+    /** lease isn't commited */
+    bool fBinding;
+
+    /** Timestamp when lease commited. */
+    uint64_t u64TimestampLeasingStarted;
+    /** Period when lease is expired in secs. */
+    uint32_t u32LeaseExpirationPeriod;
+
+    /** timestamp when lease was bound */
+    uint64_t u64TimestampBindingStarted;
+    /* Period when binding is expired in secs. */
+    uint32_t u32BindExpirationPeriod;
+
+    MapOptionId2RawOption options;
+
+    NetworkConfigEntity *pCfg;
+};
+
+#endif /* !VBOX_INCLUDED_SRC_DHCP_ClientDataInt_h */
diff --git a/src/VBox/NetworkServices/DHCP/Config.cpp b/src/VBox/NetworkServices/DHCP/Config.cpp
new file mode 100644
index 00000000..b1d09c78
--- /dev/null
+++ b/src/VBox/NetworkServices/DHCP/Config.cpp
@@ -0,0 +1,1493 @@
+/* $Id: Config.cpp $ */
+/** @file
+ * Configuration for DHCP.
+ */
+
+/*
+ * Copyright (C) 2013-2019 Oracle Corporation
+ *
+ * This file is part of VirtualBox Open Source Edition (OSE), as
+ * available from http://www.virtualbox.org. This file is free software;
+ * you can redistribute it and/or modify it under the terms of the GNU
+ * General Public License (GPL) as published by the Free Software
+ * Foundation, in version 2 as it comes in the "COPYING" file of the
+ * VirtualBox OSE distribution. VirtualBox OSE is distributed in the
+ * hope that it will be useful, but WITHOUT ANY WARRANTY of any kind.
+ */
+
+
+/**
+ * XXX: license.
+ */
+
+#include <iprt/asm.h>
+#include <iprt/getopt.h>
+#include <iprt/net.h>
+#include <iprt/time.h>
+
+#include <VBox/sup.h>
+#include <VBox/intnet.h>
+#include <VBox/intnetinline.h>
+#include <VBox/vmm/vmm.h>
+#include <VBox/version.h>
+
+#include <VBox/com/array.h>
+#include <VBox/com/string.h>
+
+#include <iprt/cpp/xml.h>
+
+#define BASE_SERVICES_ONLY
+#include "../NetLib/VBoxNetBaseService.h"
+#include "../NetLib/VBoxNetLib.h"
+#include "../NetLib/shared_ptr.h"
+
+#include <list>
+#include <vector>
+#include <map>
+#include <string>
+
+#include "Config.h"
+#include "ClientDataInt.h"
+
+bool operator== (const Lease& lhs, const Lease& rhs)
+{
+    return (lhs.m.get() == rhs.m.get());
+}
+
+
+bool operator!= (const Lease& lhs, const Lease& rhs)
+{
+    return !(lhs == rhs);
+}
+
+
+bool operator< (const Lease& lhs, const Lease& rhs)
+{
+    return (   (lhs.getAddress() < rhs.getAddress())
+            || (lhs.issued() < rhs.issued()));
+}
+/* consts */
+
+const NullConfigEntity *g_NullConfig = new NullConfigEntity();
+RootConfigEntity *g_RootConfig = new RootConfigEntity(std::string("ROOT"), 1200 /* 20 min. */);
+const ClientMatchCriteria *g_AnyClient = new AnyClientMatchCriteria();
+
+static ConfigurationManager *g_ConfigurationManager = ConfigurationManager::getConfigurationManager();
+
+NetworkManager *NetworkManager::g_NetworkManager;
+
+bool MACClientMatchCriteria::check(const Client& client) const
+{
+    return (client == m_mac);
+}
+
+
+int BaseConfigEntity::match(Client& client, BaseConfigEntity **cfg)
+{
+    int iMatch = (m_criteria && m_criteria->check(client) ? m_MatchLevel : 0);
+    if (m_children.empty())
+    {
+        if (iMatch > 0)
+        {
+            *cfg = this;
+            return iMatch;
+        }
+    }
+    else
+    {
+        *cfg = this;
+        /* XXX: hack */
+        BaseConfigEntity *matching = this;
+        int matchingLevel = m_MatchLevel;
+
+        for (std::vector<BaseConfigEntity *>::iterator it = m_children.begin();
+             it != m_children.end();
+             ++it)
+        {
+            iMatch = (*it)->match(client, &matching);
+            if (iMatch > matchingLevel)
+            {
+                *cfg = matching;
+                matchingLevel = iMatch;
+            }
+        }
+        return matchingLevel;
+    }
+    return iMatch;
+}
+
+/* Client */
+/* Configs
+    NetworkConfigEntity(std::string name,
+                        ConfigEntity* pCfg,
+                        ClientMatchCriteria* criteria,
+                        RTNETADDRIPV4& networkID,
+                        RTNETADDRIPV4& networkMask)
+*/
+static const RTNETADDRIPV4 g_AnyIpv4 = {0};
+static const RTNETADDRIPV4 g_AllIpv4 = {0xffffffff};
+RootConfigEntity::RootConfigEntity(std::string name, uint32_t expPeriod):
+  NetworkConfigEntity(name, g_NullConfig, g_AnyClient, g_AnyIpv4, g_AllIpv4)
+{
+    m_MatchLevel = 2;
+    m_u32ExpirationPeriod = expPeriod;
+}
+
+/* Configuration Manager */
+struct ConfigurationManager::Data
+{
+    Data():fFileExists(false){}
+
+    MapLease2Ip4Address  m_allocations;
+    Ipv4AddressContainer m_nameservers;
+    Ipv4AddressContainer m_routers;
+
+    std::string          m_domainName;
+    VecClient            m_clients;
+    com::Utf8Str         m_leaseStorageFilename;
+    bool                 fFileExists;
+};
+
+ConfigurationManager *ConfigurationManager::getConfigurationManager()
+{
+    if (!g_ConfigurationManager)
+
+
+    {
+        g_ConfigurationManager = new ConfigurationManager();
+        g_ConfigurationManager->init();
+    }
+
+    return g_ConfigurationManager;
+}
+
+
+const std::string tagXMLLeases = "Leases";
+const std::string tagXMLLeasesAttributeVersion = "version";
+const std::string tagXMLLeasesVersion_1_0 = "1.0";
+const std::string tagXMLLease = "Lease";
+const std::string tagXMLLeaseAttributeMac = "mac";
+const std::string tagXMLLeaseAttributeNetwork = "network";
+const std::string tagXMLLeaseAddress = "Address";
+const std::string tagXMLAddressAttributeValue = "value";
+const std::string tagXMLLeaseTime = "Time";
+const std::string tagXMLTimeAttributeIssued = "issued";
+const std::string tagXMLTimeAttributeExpiration = "expiration";
+const std::string tagXMLLeaseOptions = "Options";
+
+/**
+ * @verbatim
+   <Leases version="1.0">
+     <Lease mac="" network=""/>
+      <Address value=""/>
+      <Time issued="" expiration=""/>
+      <options>
+        <option name="" type=""/>
+        </option>
+      </options>
+     </Lease>
+   </Leases>
+   @endverbatim
+ */
+int ConfigurationManager::loadFromFile(const com::Utf8Str& leaseStorageFileName)
+{
+    m->m_leaseStorageFilename = leaseStorageFileName;
+
+    xml::XmlFileParser parser;
+    xml::Document doc;
+
+    try {
+        parser.read(m->m_leaseStorageFilename.c_str(), doc);
+    }
+    catch (...)
+    {
+        return VINF_SUCCESS;
+    }
+
+    /* XML parsing */
+    xml::ElementNode *root = doc.getRootElement();
+
+    if (!root || !root->nameEquals(tagXMLLeases.c_str()))
+    {
+        m->fFileExists = false;
+        return VERR_NOT_FOUND;
+    }
+
+    com::Utf8Str version;
+    if (root)
+        root->getAttributeValue(tagXMLLeasesAttributeVersion.c_str(), version);
+
+    /* XXX: version check */
+    xml::NodesLoop leases(*root);
+
+    const xml::ElementNode *lease;
+    while ((lease = leases.forAllNodes()))
+    {
+        if (!lease->nameEquals(tagXMLLease.c_str()))
+            continue;
+
+        ClientData *data = new ClientData();
+        Lease l(data);
+        if (l.fromXML(lease))
+        {
+
+            m->m_allocations.insert(MapLease2Ip4AddressPair(l, l.getAddress()));
+
+
+            NetworkConfigEntity *pNetCfg = NULL;
+            Client c(data);
+            int rc = g_RootConfig->match(c, (BaseConfigEntity **)&pNetCfg);
+            Assert(rc >= 0 && pNetCfg); RT_NOREF(rc);
+
+            l.setConfig(pNetCfg);
+
+            m->m_clients.push_back(c);
+        }
+    }
+
+    return VINF_SUCCESS;
+}
+
+
+int ConfigurationManager::saveToFile()
+{
+    if (m->m_leaseStorageFilename.isEmpty())
+        return VINF_SUCCESS;
+
+    xml::Document doc;
+
+    xml::ElementNode *root = doc.createRootElement(tagXMLLeases.c_str());
+    if (!root)
+        return VERR_INTERNAL_ERROR;
+
+    root->setAttribute(tagXMLLeasesAttributeVersion.c_str(), tagXMLLeasesVersion_1_0.c_str());
+
+    for(MapLease2Ip4AddressConstIterator it = m->m_allocations.begin();
+        it != m->m_allocations.end(); ++it)
+    {
+        xml::ElementNode *lease = root->createChild(tagXMLLease.c_str());
+        if (!it->first.toXML(lease))
+        {
+            /* XXX: todo logging + error handling */
+        }
+    }
+
+    try {
+        xml::XmlFileWriter writer(doc);
+        writer.write(m->m_leaseStorageFilename.c_str(), true);
+    } catch(...){}
+
+    return VINF_SUCCESS;
+}
+
+
+int ConfigurationManager::extractRequestList(PCRTNETBOOTP pDhcpMsg, size_t cbDhcpMsg, RawOption& rawOpt)
+{
+    return ConfigurationManager::findOption(RTNET_DHCP_OPT_PARAM_REQ_LIST, pDhcpMsg, cbDhcpMsg, rawOpt);
+}
+
+
+Client ConfigurationManager::getClientByDhcpPacket(const RTNETBOOTP *pDhcpMsg, size_t cbDhcpMsg)
+{
+
+    VecClientIterator it;
+    bool fDhcpValid = false;
+    uint8_t uMsgType = 0;
+
+    fDhcpValid = RTNetIPv4IsDHCPValid(NULL, pDhcpMsg, cbDhcpMsg, &uMsgType);
+    AssertReturn(fDhcpValid, Client::NullClient);
+
+    LogFlowFunc(("dhcp:mac:%RTmac\n", &pDhcpMsg->bp_chaddr.Mac));
+    /* 1st. client IDs */
+    for ( it = m->m_clients.begin();
+         it != m->m_clients.end();
+         ++it)
+    {
+        if ((*it) == pDhcpMsg->bp_chaddr.Mac)
+        {
+            LogFlowFunc(("client:mac:%RTmac\n",  it->getMacAddress()));
+            /* check timestamp that request wasn't expired. */
+            return (*it);
+        }
+    }
+
+    if (it == m->m_clients.end())
+    {
+        /* We hasn't got any session for this client */
+        Client c;
+        c.initWithMac(pDhcpMsg->bp_chaddr.Mac);
+        m->m_clients.push_back(c);
+        return m->m_clients.back();
+    }
+
+    return Client::NullClient;
+}
+
+/**
+ * Finds an option.
+ *
+ * @returns On success, a pointer to the first byte in the option data (no none
+ *          then it'll be the byte following the 0 size field) and *pcbOpt set
+ *          to the option length.
+ *          On failure, NULL is returned and *pcbOpt unchanged.
+ *
+ * @param   uOption     The option to search for.
+ * @param   pDhcpMsg    The DHCP message.
+ *                      that this is adjusted if the option length is larger
+ *                      than the message buffer.
+ * @param   cbDhcpMsg   Size of the DHCP message.
+ * @param   opt         The actual option we found.
+ */
+int
+ConfigurationManager::findOption(uint8_t uOption, PCRTNETBOOTP pDhcpMsg, size_t cbDhcpMsg, RawOption& opt)
+{
+    Assert(uOption != RTNET_DHCP_OPT_PAD);
+    Assert(uOption != RTNET_DHCP_OPT_END);
+
+    /*
+     * Validate the DHCP bits and figure the max size of the options in the vendor field.
+     */
+    if (cbDhcpMsg <= RT_UOFFSETOF(RTNETBOOTP, bp_vend.Dhcp.dhcp_opts))
+        return VERR_INVALID_PARAMETER;
+
+    if (pDhcpMsg->bp_vend.Dhcp.dhcp_cookie != RT_H2N_U32_C(RTNET_DHCP_COOKIE))
+        return VERR_INVALID_PARAMETER;
+
+    size_t cbLeft = cbDhcpMsg - RT_UOFFSETOF(RTNETBOOTP, bp_vend.Dhcp.dhcp_opts);
+    if (cbLeft > RTNET_DHCP_OPT_SIZE)
+        cbLeft = RTNET_DHCP_OPT_SIZE;
+
+    /*
+     * Search the vendor field.
+     */
+    uint8_t const  *pb = &pDhcpMsg->bp_vend.Dhcp.dhcp_opts[0];
+    while (pb && cbLeft > 0)
+    {
+        uint8_t uCur  = *pb;
+        if (uCur == RTNET_DHCP_OPT_PAD)
+        {
+            cbLeft--;
+            pb++;
+        }
+        else if (uCur == RTNET_DHCP_OPT_END)
+            break;
+        else if (cbLeft <= 1)
+            break;
+        else
+        {
+            uint8_t cbCur = pb[1];
+            if (cbCur > cbLeft - 2)
+                cbCur = (uint8_t)(cbLeft - 2);
+            if (uCur == uOption)
+            {
+                opt.u8OptId = uCur;
+                memcpy(opt.au8RawOpt, pb+2, cbCur);
+                opt.cbRawOpt = cbCur;
+                return VINF_SUCCESS;
+            }
+            pb     += cbCur + 2;
+            cbLeft -= cbCur + 2;
+        }
+    }
+
+    /** @todo search extended dhcp option field(s) when present */
+
+    return VERR_NOT_FOUND;
+}
+
+
+/**
+ * We bind lease for client till it continue with it on DHCPREQUEST.
+ */
+Lease ConfigurationManager::allocateLease4Client(const Client& client, PCRTNETBOOTP pDhcpMsg, size_t cbDhcpMsg)
+{
+    {
+        /**
+         * This mean that client has already bound or commited lease.
+         * If we've it happens it means that we received DHCPDISCOVER twice.
+         */
+        const Lease l = client.lease();
+        if (l != Lease::NullLease)
+        {
+            /* Here we should take lease from the m_allocation which was feed with leases
+             *  on start
+             */
+            if (l.isExpired())
+            {
+                expireLease4Client(const_cast<Client&>(client));
+                if (!l.isExpired())
+                    return l;
+            }
+            else
+            {
+                AssertReturn(l.getAddress().u != 0, Lease::NullLease);
+                return l;
+            }
+        }
+    }
+
+    RTNETADDRIPV4 hintAddress;
+    RawOption opt;
+    NetworkConfigEntity *pNetCfg;
+
+    Client cl(client);
+    AssertReturn(g_RootConfig->match(cl, (BaseConfigEntity **)&pNetCfg) > 0, Lease::NullLease);
+
+    /* DHCPDISCOVER MAY contain request address */
+    hintAddress.u = 0;
+    int rc = findOption(RTNET_DHCP_OPT_REQ_ADDR, pDhcpMsg, cbDhcpMsg, opt);
+    if (RT_SUCCESS(rc))
+    {
+        hintAddress.u = *(uint32_t *)opt.au8RawOpt;
+        if (   RT_H2N_U32(hintAddress.u) < RT_H2N_U32(pNetCfg->lowerIp().u)
+            || RT_H2N_U32(hintAddress.u) > RT_H2N_U32(pNetCfg->upperIp().u))
+            hintAddress.u = 0; /* clear hint */
+    }
+
+    if (   hintAddress.u
+        && !isAddressTaken(hintAddress))
+    {
+        Lease l(cl);
+        l.setConfig(pNetCfg);
+        l.setAddress(hintAddress);
+        m->m_allocations.insert(MapLease2Ip4AddressPair(l, hintAddress));
+        return l;
+    }
+
+    uint32_t u32 = 0;
+    for(u32 = RT_H2N_U32(pNetCfg->lowerIp().u);
+        u32 <= RT_H2N_U32(pNetCfg->upperIp().u);
+        ++u32)
+    {
+        RTNETADDRIPV4 address;
+        address.u = RT_H2N_U32(u32);
+        if (!isAddressTaken(address))
+        {
+            Lease l(cl);
+            l.setConfig(pNetCfg);
+            l.setAddress(address);
+            m->m_allocations.insert(MapLease2Ip4AddressPair(l, address));
+            return l;
+        }
+    }
+
+    return Lease::NullLease;
+}
+
+
+int ConfigurationManager::commitLease4Client(Client& client)
+{
+    Lease l = client.lease();
+    AssertReturn(l != Lease::NullLease, VERR_INTERNAL_ERROR);
+
+    l.bindingPhase(false);
+    const NetworkConfigEntity *pCfg = l.getConfig();
+
+    AssertPtr(pCfg);
+    l.setExpiration(pCfg->expirationPeriod());
+    l.phaseStart(RTTimeMilliTS());
+
+    saveToFile();
+
+    return VINF_SUCCESS;
+}
+
+
+int ConfigurationManager::expireLease4Client(Client& client)
+{
+    Lease l = client.lease();
+    AssertReturn(l != Lease::NullLease, VERR_INTERNAL_ERROR);
+
+    if (l.isInBindingPhase())
+    {
+
+        MapLease2Ip4AddressIterator it = m->m_allocations.find(l);
+        AssertReturn(it != m->m_allocations.end(), VERR_NOT_FOUND);
+
+        /*
+         * XXX: perhaps it better to keep this allocation ????
+         */
+        m->m_allocations.erase(it);
+
+        l.expire();
+        return VINF_SUCCESS;
+    }
+
+    l = Lease(client); /* re-new */
+    return VINF_SUCCESS;
+}
+
+
+bool ConfigurationManager::isAddressTaken(const RTNETADDRIPV4& addr, Lease& lease)
+{
+    MapLease2Ip4AddressIterator it;
+
+    for (it = m->m_allocations.begin();
+         it != m->m_allocations.end();
+         ++it)
+    {
+        if (it->second.u == addr.u)
+        {
+            if (lease != Lease::NullLease)
+                lease = it->first;
+
+            return true;
+        }
+    }
+    lease = Lease::NullLease;
+    return false;
+}
+
+
+bool ConfigurationManager::isAddressTaken(const RTNETADDRIPV4& addr)
+{
+    Lease ignore;
+    return isAddressTaken(addr, ignore);
+}
+
+
+NetworkConfigEntity *ConfigurationManager::addNetwork(NetworkConfigEntity *,
+                                    const RTNETADDRIPV4& networkId,
+                                    const RTNETADDRIPV4& netmask,
+                                    RTNETADDRIPV4& LowerAddress,
+                                    RTNETADDRIPV4& UpperAddress)
+{
+        static int id;
+        char name[64];
+
+        RTStrPrintf(name, RT_ELEMENTS(name), "network-%d", id);
+        std::string strname(name);
+        id++;
+
+
+        if (!LowerAddress.u)
+            LowerAddress = networkId;
+
+        if (!UpperAddress.u)
+            UpperAddress.u = networkId.u | (~netmask.u);
+
+        return new NetworkConfigEntity(strname,
+                            g_RootConfig,
+                            g_AnyClient,
+                            5,
+                            networkId,
+                            netmask,
+                            LowerAddress,
+                            UpperAddress);
+}
+
+HostConfigEntity *ConfigurationManager::addHost(NetworkConfigEntity* pCfg,
+                                                const RTNETADDRIPV4& address,
+                                                ClientMatchCriteria *criteria)
+{
+    static int id;
+    char name[64];
+
+    RTStrPrintf(name, RT_ELEMENTS(name), "host-%d", id);
+    std::string strname(name);
+    id++;
+
+    return new HostConfigEntity(address, strname, pCfg, criteria);
+}
+
+int ConfigurationManager::addToAddressList(uint8_t u8OptId, RTNETADDRIPV4& address)
+{
+    switch(u8OptId)
+    {
+        case RTNET_DHCP_OPT_DNS:
+            m->m_nameservers.push_back(address);
+            break;
+        case RTNET_DHCP_OPT_ROUTERS:
+            m->m_routers.push_back(address);
+            break;
+        default:
+            Log(("dhcp-opt: list (%d) unsupported\n", u8OptId));
+    }
+    return VINF_SUCCESS;
+}
+
+
+int ConfigurationManager::flushAddressList(uint8_t u8OptId)
+{
+    switch(u8OptId)
+    {
+        case RTNET_DHCP_OPT_DNS:
+            m->m_nameservers.clear();
+            break;
+        case RTNET_DHCP_OPT_ROUTERS:
+            m->m_routers.clear();
+            break;
+        default:
+            Log(("dhcp-opt: list (%d) unsupported\n", u8OptId));
+    }
+    return VINF_SUCCESS;
+}
+
+
+const Ipv4AddressContainer& ConfigurationManager::getAddressList(uint8_t u8OptId)
+{
+    switch(u8OptId)
+    {
+        case RTNET_DHCP_OPT_DNS:
+            return m->m_nameservers;
+
+        case RTNET_DHCP_OPT_ROUTERS:
+            return m->m_routers;
+
+    }
+    /* XXX: Grrr !!! */
+    return m_empty;
+}
+
+
+int ConfigurationManager::setString(uint8_t u8OptId, const std::string& str)
+{
+    switch (u8OptId)
+    {
+        case RTNET_DHCP_OPT_DOMAIN_NAME:
+            m->m_domainName = str;
+            break;
+        default:
+            break;
+    }
+
+    return VINF_SUCCESS;
+}
+
+
+const std::string &ConfigurationManager::getString(uint8_t u8OptId)
+{
+    switch (u8OptId)
+    {
+        case RTNET_DHCP_OPT_DOMAIN_NAME:
+            if (m->m_domainName.length())
+                return m->m_domainName;
+            return m_noString;
+        default:
+            break;
+    }
+
+    return m_noString;
+}
+
+
+void ConfigurationManager::init()
+{
+    m = new ConfigurationManager::Data();
+}
+
+
+ConfigurationManager::~ConfigurationManager() { if (m) delete m; }
+
+/**
+ * Network manager
+ */
+struct NetworkManager::Data
+{
+    Data()
+    {
+        RT_ZERO(BootPReplyMsg);
+        cbBooPReplyMsg = 0;
+
+        m_OurAddress.u = 0;
+        m_OurNetmask.u = 0;
+        RT_ZERO(m_OurMac);
+    }
+
+    union {
+        RTNETBOOTP BootPHeader;
+        uint8_t au8Storage[1024];
+    } BootPReplyMsg;
+    int cbBooPReplyMsg;
+
+    RTNETADDRIPV4 m_OurAddress;
+    RTNETADDRIPV4 m_OurNetmask;
+    RTMAC m_OurMac;
+
+    ComPtr<IDHCPServer>  m_DhcpServer;
+    const VBoxNetHlpUDPService *m_service;
+};
+
+
+NetworkManager::NetworkManager():m(NULL)
+{
+    m = new NetworkManager::Data();
+}
+
+
+NetworkManager::~NetworkManager()
+{
+    delete m;
+    m = NULL;
+}
+
+
+NetworkManager *NetworkManager::getNetworkManager(ComPtr<IDHCPServer> aDhcpServer)
+{
+    if (!g_NetworkManager)
+    {
+        g_NetworkManager = new NetworkManager();
+        g_NetworkManager->m->m_DhcpServer = aDhcpServer;
+    }
+
+    return g_NetworkManager;
+}
+
+
+const RTNETADDRIPV4& NetworkManager::getOurAddress() const
+{
+    return m->m_OurAddress;
+}
+
+
+const RTNETADDRIPV4& NetworkManager::getOurNetmask() const
+{
+    return m->m_OurNetmask;
+}
+
+
+const RTMAC& NetworkManager::getOurMac() const
+{
+    return m->m_OurMac;
+}
+
+
+void NetworkManager::setOurAddress(const RTNETADDRIPV4& aAddress)
+{
+    m->m_OurAddress = aAddress;
+}
+
+
+void NetworkManager::setOurNetmask(const RTNETADDRIPV4& aNetmask)
+{
+    m->m_OurNetmask = aNetmask;
+}
+
+
+void NetworkManager::setOurMac(const RTMAC& aMac)
+{
+    m->m_OurMac = aMac;
+}
+
+
+void NetworkManager::setService(const VBoxNetHlpUDPService *srv)
+{
+    m->m_service = srv;
+}
+
+/**
+ * Network manager creates DHCPOFFER datagramm
+ */
+int NetworkManager::offer4Client(const Client& client, uint32_t u32Xid,
+                                 uint8_t *pu8ReqList, int cReqList)
+{
+    Lease l(client); /* XXX: oh, it looks badly, but now we have lease */
+    prepareReplyPacket4Client(client, u32Xid);
+
+    RTNETADDRIPV4 address = l.getAddress();
+    m->BootPReplyMsg.BootPHeader.bp_yiaddr =  address;
+
+    /* Ubuntu ???*/
+    m->BootPReplyMsg.BootPHeader.bp_ciaddr =  address;
+
+    /* options:
+     * - IP lease time
+     * - message type
+     * - server identifier
+     */
+    RawOption opt;
+    RT_ZERO(opt);
+
+    std::vector<RawOption> extra;
+    opt.u8OptId = RTNET_DHCP_OPT_MSG_TYPE;
+    opt.au8RawOpt[0] = RTNET_DHCP_MT_OFFER;
+    opt.cbRawOpt = 1;
+    extra.push_back(opt);
+
+    opt.u8OptId = RTNET_DHCP_OPT_LEASE_TIME;
+
+    const NetworkConfigEntity *pCfg = l.getConfig();
+    AssertPtr(pCfg);
+
+    *(uint32_t *)opt.au8RawOpt = RT_H2N_U32(pCfg->expirationPeriod());
+    opt.cbRawOpt = sizeof(RTNETADDRIPV4);
+
+    extra.push_back(opt);
+
+    processParameterReqList(client, pu8ReqList, cReqList, extra);
+
+    return doReply(client, extra);
+}
+
+/**
+ * Network manager creates DHCPACK
+ */
+int NetworkManager::ack(const Client& client, uint32_t u32Xid,
+                        uint8_t *pu8ReqList, int cReqList)
+{
+    RTNETADDRIPV4 address;
+
+    prepareReplyPacket4Client(client, u32Xid);
+
+    Lease l = client.lease();
+    address = l.getAddress();
+    m->BootPReplyMsg.BootPHeader.bp_ciaddr =  address;
+
+
+    /* rfc2131 4.3.1 is about DHCPDISCOVER and this value is equal to ciaddr from
+     * DHCPREQUEST or 0 ...
+     * XXX: Using addressHint is not correct way to initialize [cy]iaddress...
+     */
+    m->BootPReplyMsg.BootPHeader.bp_ciaddr = address;
+    m->BootPReplyMsg.BootPHeader.bp_yiaddr = address;
+
+    Assert(m->BootPReplyMsg.BootPHeader.bp_yiaddr.u);
+
+    /* options:
+     * - IP address lease time (if DHCPREQUEST)
+     * - message type
+     * - server identifier
+     */
+    RawOption opt;
+    RT_ZERO(opt);
+
+    std::vector<RawOption> extra;
+    opt.u8OptId = RTNET_DHCP_OPT_MSG_TYPE;
+    opt.au8RawOpt[0] = RTNET_DHCP_MT_ACK;
+    opt.cbRawOpt = 1;
+    extra.push_back(opt);
+
+    /*
+     * XXX: lease time should be conditional. If on dhcprequest then tim should be provided,
+     * else on dhcpinform it mustn't.
+     */
+    opt.u8OptId = RTNET_DHCP_OPT_LEASE_TIME;
+    *(uint32_t *)opt.au8RawOpt = RT_H2N_U32(l.getExpiration());
+    opt.cbRawOpt = sizeof(RTNETADDRIPV4);
+    extra.push_back(opt);
+
+    processParameterReqList(client, pu8ReqList, cReqList, extra);
+
+    return doReply(client, extra);
+}
+
+/**
+ * Network manager creates DHCPNAK
+ */
+int NetworkManager::nak(const Client& client, uint32_t u32Xid)
+{
+
+    Lease l = client.lease();
+    if (l == Lease::NullLease)
+        return VERR_INTERNAL_ERROR;
+
+    prepareReplyPacket4Client(client, u32Xid);
+
+    /* this field filed in prepareReplyPacket4Session, and
+     * RFC 2131 require to have it zero fo NAK.
+     */
+    m->BootPReplyMsg.BootPHeader.bp_yiaddr.u = 0;
+
+    /* options:
+     * - message type (if DHCPREQUEST)
+     * - server identifier
+     */
+    RawOption opt;
+    std::vector<RawOption> extra;
+
+    opt.u8OptId = RTNET_DHCP_OPT_MSG_TYPE;
+    opt.au8RawOpt[0] = RTNET_DHCP_MT_NAC;
+    opt.cbRawOpt = 1;
+    extra.push_back(opt);
+
+    return doReply(client, extra);
+}
+
+/**
+ *
+ */
+int NetworkManager::prepareReplyPacket4Client(const Client& client, uint32_t u32Xid)
+{
+    RT_ZERO(m->BootPReplyMsg);
+
+    m->BootPReplyMsg.BootPHeader.bp_op     = RTNETBOOTP_OP_REPLY;
+    m->BootPReplyMsg.BootPHeader.bp_htype  = RTNET_ARP_ETHER;
+    m->BootPReplyMsg.BootPHeader.bp_hlen   = sizeof(RTMAC);
+    m->BootPReplyMsg.BootPHeader.bp_hops   = 0;
+    m->BootPReplyMsg.BootPHeader.bp_xid    = u32Xid;
+    m->BootPReplyMsg.BootPHeader.bp_secs   = 0;
+    /* XXX: bp_flags should be processed specially */
+    m->BootPReplyMsg.BootPHeader.bp_flags  = 0;
+    m->BootPReplyMsg.BootPHeader.bp_ciaddr.u = 0;
+    m->BootPReplyMsg.BootPHeader.bp_giaddr.u = 0;
+
+    m->BootPReplyMsg.BootPHeader.bp_chaddr.Mac = client.getMacAddress();
+
+    const Lease l = client.lease();
+    m->BootPReplyMsg.BootPHeader.bp_yiaddr = l.getAddress();
+    m->BootPReplyMsg.BootPHeader.bp_siaddr.u = 0;
+
+
+    m->BootPReplyMsg.BootPHeader.bp_vend.Dhcp.dhcp_cookie = RT_H2N_U32_C(RTNET_DHCP_COOKIE);
+
+    memset(&m->BootPReplyMsg.BootPHeader.bp_vend.Dhcp.dhcp_opts[0],
+           '\0',
+           RTNET_DHCP_OPT_SIZE);
+
+    return VINF_SUCCESS;
+}
+
+
+int NetworkManager::doReply(const Client& client, const std::vector<RawOption>& extra)
+{
+    int rc;
+
+    /*
+      Options....
+     */
+    VBoxNetDhcpWriteCursor Cursor(&m->BootPReplyMsg.BootPHeader, RTNET_DHCP_NORMAL_SIZE);
+
+    /* The basics */
+
+    Cursor.optIPv4Addr(RTNET_DHCP_OPT_SERVER_ID, m->m_OurAddress);
+
+    const Lease l = client.lease();
+    const std::map<uint8_t, RawOption>& options = l.options();
+
+    for(std::vector<RawOption>::const_iterator it = extra.begin();
+        it != extra.end(); ++it)
+    {
+        if (!Cursor.begin(it->u8OptId, it->cbRawOpt))
+            break;
+        Cursor.put(it->au8RawOpt, it->cbRawOpt);
+
+    }
+
+    for(std::map<uint8_t, RawOption>::const_iterator it = options.begin();
+        it != options.end(); ++it)
+    {
+        if (!Cursor.begin(it->second.u8OptId, it->second.cbRawOpt))
+            break;
+        Cursor.put(it->second.au8RawOpt, it->second.cbRawOpt);
+
+    }
+
+    Cursor.optEnd();
+
+    /*
+     */
+#if 0
+    /** @todo need to see someone set this flag to check that it's correct. */
+    if (!(pDhcpMsg->bp_flags & RTNET_DHCP_FLAGS_NO_BROADCAST))
+    {
+        rc = VBoxNetUDPUnicast(m_pSession,
+                               m_hIf,
+                               m_pIfBuf,
+                               m_OurAddress,
+                               &m_OurMac,
+                               RTNETIPV4_PORT_BOOTPS,                 /* sender */
+                               IPv4AddrBrdCast,
+                               &BootPReplyMsg.BootPHeader->bp_chaddr.Mac,
+                               RTNETIPV4_PORT_BOOTPC,    /* receiver */
+                               &BootPReplyMsg, cbBooPReplyMsg);
+    }
+    else
+#endif
+        rc = m->m_service->hlpUDPBroadcast(RTNETIPV4_PORT_BOOTPS,               /* sender */
+                                           RTNETIPV4_PORT_BOOTPC,
+                                           &m->BootPReplyMsg,
+                                           RTNET_DHCP_NORMAL_SIZE);
+
+    AssertRCReturn(rc,rc);
+
+    return VINF_SUCCESS;
+}
+
+
+/*
+ * XXX: TODO: Share decoding code with DHCPServer::addOption.
+ */
+static int parseDhcpOptionText(const char *pszText,
+                               int *pOptCode, char **ppszOptText, int *pOptEncoding)
+{
+    uint8_t u8Code;
+    uint32_t u32Enc;
+    char *pszNext;
+    int rc;
+
+    rc = RTStrToUInt8Ex(pszText, &pszNext, 10, &u8Code);
+    if (!RT_SUCCESS(rc))
+        return VERR_PARSE_ERROR;
+
+    switch (*pszNext)
+    {
+        case ':':           /* support legacy format too */
+        {
+            u32Enc = 0;
+            break;
+        }
+
+        case '=':
+        {
+            u32Enc = 1;
+            break;
+        }
+
+        case '@':
+        {
+            rc = RTStrToUInt32Ex(pszNext + 1, &pszNext, 10, &u32Enc);
+            if (!RT_SUCCESS(rc))
+                return VERR_PARSE_ERROR;
+            if (*pszNext != '=')
+                return VERR_PARSE_ERROR;
+            break;
+        }
+
+        default:
+            return VERR_PARSE_ERROR;
+    }
+
+    *pOptCode = u8Code;
+    *ppszOptText = pszNext + 1;
+    *pOptEncoding = (int)u32Enc;
+
+    return VINF_SUCCESS;
+}
+
+
+static int fillDhcpOption(RawOption &opt, const std::string &OptText, int OptEncoding)
+{
+    int rc;
+
+    if (OptEncoding == DhcpOptEncoding_Hex)
+    {
+        if (OptText.empty())
+            return VERR_INVALID_PARAMETER;
+
+        size_t cbRawOpt = 0;
+        char *pszNext = const_cast<char *>(OptText.c_str());
+        while (*pszNext != '\0')
+        {
+            if (cbRawOpt >= RT_ELEMENTS(opt.au8RawOpt))
+                return VERR_INVALID_PARAMETER;
+
+            uint8_t u8Byte;
+            rc = RTStrToUInt8Ex(pszNext, &pszNext, 16, &u8Byte);
+            if (!RT_SUCCESS(rc))
+                return rc;
+
+            if (*pszNext == ':')
+                ++pszNext;
+            else if (*pszNext != '\0')
+                return VERR_PARSE_ERROR;
+
+            opt.au8RawOpt[cbRawOpt] = u8Byte;
+            ++cbRawOpt;
+        }
+        opt.cbRawOpt = (uint8_t)cbRawOpt;
+    }
+    else if (OptEncoding == DhcpOptEncoding_Legacy)
+    {
+        /*
+         * XXX: TODO: encode "known" option opt.u8OptId
+         */
+        return VERR_INVALID_PARAMETER;
+    }
+
+    return VINF_SUCCESS;
+}
+
+
+int NetworkManager::processParameterReqList(const Client& client, const uint8_t *pu8ReqList,
+                                            int cReqList, std::vector<RawOption>& extra)
+{
+    int rc;
+
+    const Lease l = client.lease();
+
+    const NetworkConfigEntity *pNetCfg = l.getConfig();
+
+    /*
+     * XXX: Brute-force.  Unfortunately, there's no notification event
+     * for changes.  Should at least cache the options for a short
+     * time, enough to last discover/offer/request/ack cycle.
+     */
+    typedef std::map< int, std::pair<std::string, int> > DhcpOptionMap;
+    DhcpOptionMap OptMap;
+
+    if (!m->m_DhcpServer.isNull())
+    {
+        com::SafeArray<BSTR> strings;
+        com::Bstr str;
+        HRESULT hrc;
+        int OptCode, OptEncoding;
+        char *pszOptText;
+
+        strings.setNull();
+        hrc = m->m_DhcpServer->COMGETTER(GlobalOptions)(ComSafeArrayAsOutParam(strings));
+        AssertComRC(hrc);
+        for (size_t i = 0; i < strings.size(); ++i)
+        {
+            com::Utf8Str encoded(strings[i]);
+            rc = parseDhcpOptionText(encoded.c_str(),
+                                     &OptCode, &pszOptText, &OptEncoding);
+            if (!RT_SUCCESS(rc))
+                continue;
+
+            OptMap[OptCode] = std::make_pair(pszOptText, OptEncoding);
+        }
+
+        const RTMAC &mac = client.getMacAddress();
+        char strMac[6*2+1] = "";
+        RTStrPrintf(strMac, sizeof(strMac), "%02x%02x%02x%02x%02x%02x",
+                    mac.au8[0], mac.au8[1], mac.au8[2],
+                    mac.au8[3], mac.au8[4], mac.au8[5]);
+
+        strings.setNull();
+        hrc = m->m_DhcpServer->GetMacOptions(com::Bstr(strMac).raw(),
+                                             ComSafeArrayAsOutParam(strings));
+        AssertComRC(hrc);
+        for (size_t i = 0; i < strings.size(); ++i)
+        {
+            com::Utf8Str text(strings[i]);
+            rc = parseDhcpOptionText(text.c_str(),
+                                     &OptCode, &pszOptText, &OptEncoding);
+            if (!RT_SUCCESS(rc))
+                continue;
+
+            OptMap[OptCode] = std::make_pair(pszOptText, OptEncoding);
+        }
+    }
+
+    /* request parameter list */
+    RawOption opt;
+    bool fIgnore;
+    uint8_t u8Req;
+    for (int idxParam = 0; idxParam < cReqList; ++idxParam)
+    {
+        fIgnore = false;
+        RT_ZERO(opt);
+        u8Req = opt.u8OptId = pu8ReqList[idxParam];
+
+        switch(u8Req)
+        {
+            case RTNET_DHCP_OPT_SUBNET_MASK:
+                ((PRTNETADDRIPV4)opt.au8RawOpt)->u = pNetCfg->netmask().u;
+                opt.cbRawOpt = sizeof(RTNETADDRIPV4);
+
+                break;
+
+            case RTNET_DHCP_OPT_ROUTERS:
+            case RTNET_DHCP_OPT_DNS:
+                {
+                    const Ipv4AddressContainer lst =
+                      g_ConfigurationManager->getAddressList(u8Req);
+                    PRTNETADDRIPV4 pAddresses = (PRTNETADDRIPV4)&opt.au8RawOpt[0];
+
+                    for (Ipv4AddressConstIterator it = lst.begin();
+                         it != lst.end();
+                         ++it)
+                    {
+                        *pAddresses = (*it);
+                        pAddresses++;
+                        opt.cbRawOpt += sizeof(RTNETADDRIPV4);
+                    }
+
+                    if (lst.empty())
+                        fIgnore = true;
+                }
+                break;
+            case RTNET_DHCP_OPT_DOMAIN_NAME:
+                {
+                    std::string domainName = g_ConfigurationManager->getString(u8Req);
+                    if (domainName == g_ConfigurationManager->m_noString)
+                    {
+                        fIgnore = true;
+                        break;
+                    }
+
+                    size_t cchLength = domainName.length();
+                    if (cchLength >= sizeof(opt.au8RawOpt))
+                        cchLength = sizeof(opt.au8RawOpt) - 1;
+                    memcpy(&opt.au8RawOpt[0], domainName.c_str(), cchLength);
+                    opt.au8RawOpt[cchLength] = '\0';
+                    opt.cbRawOpt = (uint8_t)cchLength;
+                }
+                break;
+            default:
+                {
+                    DhcpOptionMap::const_iterator it = OptMap.find((int)u8Req);
+                    if (it == OptMap.end())
+                    {
+                        Log(("opt: %d is ignored\n", u8Req));
+                        fIgnore = true;
+                    }
+                    else
+                    {
+                        std::string OptText((*it).second.first);
+                        int OptEncoding((*it).second.second);
+
+                        rc = fillDhcpOption(opt, OptText, OptEncoding);
+                        if (!RT_SUCCESS(rc))
+                        {
+                            fIgnore = true;
+                            break;
+                        }
+                    }
+                }
+                break;
+        }
+
+        if (!fIgnore)
+            extra.push_back(opt);
+
+    }
+
+    return VINF_SUCCESS;
+}
+
+/* Client */
+Client::Client()
+{
+    m = SharedPtr<ClientData>();
+}
+
+
+void Client::initWithMac(const RTMAC& mac)
+{
+    m = SharedPtr<ClientData>(new ClientData());
+    m->m_mac = mac;
+}
+
+
+bool Client::operator== (const RTMAC& mac) const
+{
+    return (m.get() && m->m_mac == mac);
+}
+
+
+const RTMAC& Client::getMacAddress() const
+{
+    return m->m_mac;
+}
+
+
+Lease Client::lease()
+{
+    if (!m.get()) return Lease::NullLease;
+
+    if (m->fHasLease)
+        return Lease(*this);
+    else
+        return Lease::NullLease;
+}
+
+
+const Lease Client::lease() const
+{
+    return const_cast<Client *>(this)->lease();
+}
+
+
+Client::Client(ClientData *data):m(SharedPtr<ClientData>(data)){}
+
+/* Lease */
+Lease::Lease()
+{
+    m = SharedPtr<ClientData>();
+}
+
+
+Lease::Lease (const Client& c)
+{
+    m = SharedPtr<ClientData>(c.m);
+    if (   !m->fHasLease
+        || (   isExpired()
+            && !isInBindingPhase()))
+    {
+        m->fHasLease = true;
+        m->fBinding = true;
+        phaseStart(RTTimeMilliTS());
+    }
+}
+
+
+bool Lease::isExpired() const
+{
+    AssertPtrReturn(m.get(), false);
+
+    if (!m->fBinding)
+        return (ASMDivU64ByU32RetU32(RTTimeMilliTS() - m->u64TimestampLeasingStarted, 1000)
+                > m->u32LeaseExpirationPeriod);
+    else
+        return (ASMDivU64ByU32RetU32(RTTimeMilliTS() - m->u64TimestampBindingStarted, 1000)
+                > m->u32BindExpirationPeriod);
+}
+
+
+void Lease::expire()
+{
+    /* XXX: TODO */
+}
+
+
+void Lease::phaseStart(uint64_t u64Start)
+{
+    if (m->fBinding)
+        m->u64TimestampBindingStarted = u64Start;
+    else
+        m->u64TimestampLeasingStarted = u64Start;
+}
+
+
+void Lease::bindingPhase(bool fOnOff)
+{
+    m->fBinding = fOnOff;
+}
+
+
+bool Lease::isInBindingPhase() const
+{
+    return m->fBinding;
+}
+
+
+uint64_t Lease::issued() const
+{
+    return m->u64TimestampLeasingStarted;
+}
+
+
+void Lease::setExpiration(uint32_t exp)
+{
+    if (m->fBinding)
+        m->u32BindExpirationPeriod = exp;
+    else
+        m->u32LeaseExpirationPeriod = exp;
+}
+
+
+uint32_t Lease::getExpiration() const
+{
+    if (m->fBinding)
+        return m->u32BindExpirationPeriod;
+    else
+        return m->u32LeaseExpirationPeriod;
+}
+
+
+RTNETADDRIPV4 Lease::getAddress() const
+{
+    return m->m_address;
+}
+
+
+void Lease::setAddress(RTNETADDRIPV4 address)
+{
+    m->m_address = address;
+}
+
+
+const NetworkConfigEntity *Lease::getConfig() const
+{
+    return m->pCfg;
+}
+
+
+void Lease::setConfig(NetworkConfigEntity *pCfg)
+{
+    m->pCfg = pCfg;
+}
+
+
+const MapOptionId2RawOption& Lease::options() const
+{
+    return m->options;
+}
+
+
+Lease::Lease(ClientData *pd):m(SharedPtr<ClientData>(pd)){}
+
+
+bool Lease::toXML(xml::ElementNode *node) const
+{
+    xml::AttributeNode *pAttribNode = node->setAttribute(tagXMLLeaseAttributeMac.c_str(),
+                                                         com::Utf8StrFmt("%RTmac", &m->m_mac));
+    if (!pAttribNode)
+        return false;
+
+    pAttribNode = node->setAttribute(tagXMLLeaseAttributeNetwork.c_str(),
+                                     com::Utf8StrFmt("%RTnaipv4", m->m_network));
+    if (!pAttribNode)
+        return false;
+
+    xml::ElementNode *pLeaseAddress = node->createChild(tagXMLLeaseAddress.c_str());
+    if (!pLeaseAddress)
+        return false;
+
+    pAttribNode = pLeaseAddress->setAttribute(tagXMLAddressAttributeValue.c_str(),
+                                              com::Utf8StrFmt("%RTnaipv4", m->m_address));
+    if (!pAttribNode)
+        return false;
+
+    xml::ElementNode *pLeaseTime = node->createChild(tagXMLLeaseTime.c_str());
+    if (!pLeaseTime)
+        return false;
+
+    pAttribNode = pLeaseTime->setAttribute(tagXMLTimeAttributeIssued.c_str(),
+                                           m->u64TimestampLeasingStarted);
+    if (!pAttribNode)
+        return false;
+
+    pAttribNode = pLeaseTime->setAttribute(tagXMLTimeAttributeExpiration.c_str(),
+                                           m->u32LeaseExpirationPeriod);
+    if (!pAttribNode)
+        return false;
+
+    return true;
+}
+
+
+bool Lease::fromXML(const xml::ElementNode *node)
+{
+    com::Utf8Str mac;
+    bool valueExists = node->getAttributeValue(tagXMLLeaseAttributeMac.c_str(), mac);
+    if (!valueExists) return false;
+    int rc = RTNetStrToMacAddr(mac.c_str(), &m->m_mac);
+    if (RT_FAILURE(rc)) return false;
+
+    com::Utf8Str network;
+    valueExists = node->getAttributeValue(tagXMLLeaseAttributeNetwork.c_str(), network);
+    if (!valueExists) return false;
+    rc = RTNetStrToIPv4Addr(network.c_str(), &m->m_network);
+    if (RT_FAILURE(rc)) return false;
+
+    /* Address */
+    const xml::ElementNode *address = node->findChildElement(tagXMLLeaseAddress.c_str());
+    if (!address) return false;
+    com::Utf8Str addressValue;
+    valueExists = address->getAttributeValue(tagXMLAddressAttributeValue.c_str(), addressValue);
+    if (!valueExists) return false;
+    rc = RTNetStrToIPv4Addr(addressValue.c_str(), &m->m_address);
+
+    /* Time */
+    const xml::ElementNode *time = node->findChildElement(tagXMLLeaseTime.c_str());
+    if (!time) return false;
+
+    valueExists = time->getAttributeValue(tagXMLTimeAttributeIssued.c_str(),
+                                          &m->u64TimestampLeasingStarted);
+    if (!valueExists) return false;
+    m->fBinding = false;
+
+    valueExists = time->getAttributeValue(tagXMLTimeAttributeExpiration.c_str(),
+                                          &m->u32LeaseExpirationPeriod);
+    if (!valueExists) return false;
+
+    m->fHasLease = true;
+    return true;
+}
+
+
+const Lease Lease::NullLease;
+
+const Client Client::NullClient;
diff --git a/src/VBox/NetworkServices/DHCP/Config.h b/src/VBox/NetworkServices/DHCP/Config.h
new file mode 100644
index 00000000..a8431686
--- /dev/null
+++ b/src/VBox/NetworkServices/DHCP/Config.h
@@ -0,0 +1,845 @@
+/* $Id: Config.h $ */
+/** @file
+ * Config.h
+ */
+
+/*
+ * Copyright (C) 2013-2019 Oracle Corporation
+ *
+ * This file is part of VirtualBox Open Source Edition (OSE), as
+ * available from http://www.virtualbox.org. This file is free software;
+ * you can redistribute it and/or modify it under the terms of the GNU
+ * General Public License (GPL) as published by the Free Software
+ * Foundation, in version 2 as it comes in the "COPYING" file of the
+ * VirtualBox OSE distribution. VirtualBox OSE is distributed in the
+ * hope that it will be useful, but WITHOUT ANY WARRANTY of any kind.
+ */
+
+#ifndef VBOX_INCLUDED_SRC_DHCP_Config_h
+#define VBOX_INCLUDED_SRC_DHCP_Config_h
+#ifndef RT_WITHOUT_PRAGMA_ONCE
+# pragma once
+#endif
+
+#include <iprt/asm-math.h>
+#include <iprt/cpp/utils.h>
+
+#include <VBox/com/ptr.h>
+#include <VBox/com/string.h>
+#include <VBox/com/VirtualBox.h>
+
+#include "../NetLib/cpp/utils.h"
+
+
+class RawOption
+{
+public:
+    RawOption()
+    {
+        /** @todo r=bird: this is crazy. */
+        RT_ZERO(*this);
+    }
+    uint8_t u8OptId;
+    uint8_t cbRawOpt;
+    uint8_t au8RawOpt[255];
+};
+
+class ClientData;
+class Client;
+class Lease;
+class BaseConfigEntity;
+
+class NetworkConfigEntity;
+class HostConfigEntity;
+class ClientMatchCriteria;
+class ConfigurationManager;
+
+/*
+ * it's a basic representation of
+ * of out undestanding what client is
+ * XXX: Client might sends Option 61 (RFC2132 9.14 "Client-identifier") signalling
+ * that we may identify it in special way
+ *
+ * XXX: Client might send Option 60 (RFC2132 9.13 "Vendor class undentifier")
+ * in response it's expected server sends Option 43 (RFC2132 8.4. "Vendor Specific Information")
+ */
+class Client
+{
+    friend class Lease;
+    friend class ConfigurationManager;
+
+    public:
+    Client();
+    void initWithMac(const RTMAC& mac);
+    bool operator== (const RTMAC& mac) const;
+    const RTMAC& getMacAddress() const;
+
+    /** Dumps client query */
+    void dump();
+
+    Lease lease();
+    const Lease lease() const;
+
+    public:
+    static const Client NullClient;
+
+    private:
+    Client(ClientData *);
+    SharedPtr<ClientData> m;
+};
+
+
+bool operator== (const Lease&, const Lease&);
+bool operator!= (const Lease&, const Lease&);
+bool operator< (const Lease&, const Lease&);
+
+
+typedef std::map<uint8_t, RawOption> MapOptionId2RawOption;
+typedef MapOptionId2RawOption::iterator MapOptionId2RawOptionIterator;
+typedef MapOptionId2RawOption::const_iterator MapOptionId2RawOptionConstIterator;
+typedef MapOptionId2RawOption::value_type MapOptionId2RawOptionValue;
+
+namespace xml {
+    class ElementNode;
+}
+
+class Lease
+{
+    friend class Client;
+    friend bool operator== (const Lease&, const Lease&);
+    //friend int ConfigurationManager::loadFromFile(const std::string&);
+    friend class ConfigurationManager;
+
+    public:
+    Lease();
+    Lease(const Client&);
+
+    bool isExpired() const;
+    void expire();
+
+    /* Depending on phase *Expiration and phaseStart initialize different values. */
+    void bindingPhase(bool);
+    void phaseStart(uint64_t u64Start);
+    bool isInBindingPhase() const;
+    /* returns 0 if in binding state */
+    uint64_t issued() const;
+
+    void setExpiration(uint32_t);
+    uint32_t getExpiration() const;
+
+    RTNETADDRIPV4 getAddress() const;
+    void setAddress(RTNETADDRIPV4);
+
+    const NetworkConfigEntity *getConfig() const;
+    void setConfig(NetworkConfigEntity *);
+
+    const MapOptionId2RawOption& options() const;
+
+    bool toXML(xml::ElementNode *) const;
+    bool fromXML(const xml::ElementNode *);
+
+    public:
+    static const Lease NullLease;
+
+    private:
+    Lease(ClientData *);
+    SharedPtr<ClientData> m;
+};
+
+
+typedef std::vector<Client> VecClient;
+typedef VecClient::iterator VecClientIterator;
+typedef VecClient::const_iterator VecClientConstIterator;
+
+typedef std::vector<RTMAC> MacAddressContainer;
+typedef MacAddressContainer::iterator MacAddressIterator;
+
+typedef std::vector<RTNETADDRIPV4> Ipv4AddressContainer;
+typedef Ipv4AddressContainer::iterator Ipv4AddressIterator;
+typedef Ipv4AddressContainer::const_iterator Ipv4AddressConstIterator;
+
+typedef std::map<Lease, RTNETADDRIPV4> MapLease2Ip4Address;
+typedef MapLease2Ip4Address::iterator MapLease2Ip4AddressIterator;
+typedef MapLease2Ip4Address::const_iterator MapLease2Ip4AddressConstIterator;
+typedef MapLease2Ip4Address::value_type MapLease2Ip4AddressPair;
+
+/**
+ *
+ */
+class ClientMatchCriteria
+{
+    public:
+    virtual bool check(const Client&) const {return false;};
+};
+
+
+class ORClientMatchCriteria: ClientMatchCriteria
+{
+    ClientMatchCriteria* m_left;
+    ClientMatchCriteria* m_right;
+    ORClientMatchCriteria(ClientMatchCriteria *left, ClientMatchCriteria *right)
+    {
+        m_left = left;
+        m_right = right;
+    }
+
+    virtual bool check(const Client& client) const
+    {
+        return (m_left->check(client) || m_right->check(client));
+    }
+};
+
+
+class ANDClientMatchCriteria: ClientMatchCriteria
+{
+public:
+    ANDClientMatchCriteria(ClientMatchCriteria *left, ClientMatchCriteria *right)
+    {
+        m_left = left;
+        m_right = right;
+    }
+
+    virtual bool check(const Client& client) const
+    {
+        return (m_left->check(client) && m_right->check(client));
+    }
+
+private:
+    ClientMatchCriteria* m_left;
+    ClientMatchCriteria* m_right;
+
+};
+
+
+class AnyClientMatchCriteria: public ClientMatchCriteria
+{
+public:
+    virtual bool check(const Client&) const
+    {
+        return true;
+    }
+};
+
+
+class MACClientMatchCriteria: public ClientMatchCriteria
+{
+public:
+    MACClientMatchCriteria(const RTMAC& mac):m_mac(mac){}
+
+    virtual bool check(const Client& client) const;
+
+private:
+    RTMAC m_mac;
+};
+
+
+#if 0
+/* XXX: Later */
+class VmSlotClientMatchCriteria: public ClientMatchCriteria
+{
+    str::string VmName;
+    uint8_t u8Slot;
+    virtual bool check(const Client& client)
+    {
+        return (   client.VmName == VmName
+                   && (   u8Slot == (uint8_t)~0 /* any */
+                       || client.u8Slot == u8Slot));
+    }
+};
+#endif
+
+
+/* Option 60 */
+class ClassClientMatchCriteria: ClientMatchCriteria{};
+/* Option 61 */
+class ClientIdentifierMatchCriteria: ClientMatchCriteria{};
+
+
+class BaseConfigEntity
+{
+    public:
+    BaseConfigEntity(const ClientMatchCriteria *criteria = NULL,
+      int matchingLevel = 0)
+      : m_criteria(criteria),
+      m_MatchLevel(matchingLevel){};
+    virtual ~BaseConfigEntity(){};
+    /* XXX */
+    int add(BaseConfigEntity *cfg)
+    {
+        m_children.push_back(cfg);
+        return 0;
+    }
+
+    /* Should return how strong matching */
+    virtual int match(Client& client, BaseConfigEntity **cfg);
+    virtual uint32_t expirationPeriod() const = 0;
+
+    protected:
+    const ClientMatchCriteria *m_criteria;
+    int m_MatchLevel;
+    std::vector<BaseConfigEntity *> m_children;
+};
+
+
+class NullConfigEntity: public BaseConfigEntity
+{
+    public:
+    NullConfigEntity(){}
+    virtual ~NullConfigEntity(){}
+    int add(BaseConfigEntity *) const { return 0;}
+    virtual uint32_t expirationPeriod() const {return 0;}
+};
+
+
+class ConfigEntity: public BaseConfigEntity
+{
+    public:
+    /* range */
+    /* match conditions */
+    ConfigEntity(std::string& name,
+                 const BaseConfigEntity *cfg,
+                 const ClientMatchCriteria *criteria,
+                 int matchingLevel = 0):
+      BaseConfigEntity(criteria, matchingLevel),
+      m_name(name),
+      m_parentCfg(cfg),
+      m_u32ExpirationPeriod(0)
+    {
+        unconst(m_parentCfg)->add(this);
+    }
+
+    virtual uint32_t expirationPeriod() const
+    {
+        if (!m_u32ExpirationPeriod)
+            return m_parentCfg->expirationPeriod();
+        else
+            return m_u32ExpirationPeriod;
+    }
+
+    /* XXX: private:*/
+    std::string m_name;
+    const BaseConfigEntity *m_parentCfg;
+    uint32_t m_u32ExpirationPeriod;
+};
+
+
+/**
+ * Network specific entries
+ */
+class NetworkConfigEntity:public ConfigEntity
+{
+public:
+    /* Address Pool matching with network declaration */
+    NetworkConfigEntity(std::string name,
+                        const BaseConfigEntity *cfg,
+                        const ClientMatchCriteria *criteria,
+                        int matchlvl,
+                        const RTNETADDRIPV4& networkID,
+                        const RTNETADDRIPV4& networkMask,
+                        const RTNETADDRIPV4& lowerIP,
+                        const RTNETADDRIPV4& upperIP):
+      ConfigEntity(name, cfg, criteria, matchlvl),
+      m_NetworkID(networkID),
+      m_NetworkMask(networkMask),
+      m_UpperIP(upperIP),
+      m_LowerIP(lowerIP)
+    {
+    };
+
+    NetworkConfigEntity(std::string name,
+                        const BaseConfigEntity *cfg,
+                        const ClientMatchCriteria *criteria,
+                        const RTNETADDRIPV4& networkID,
+                        const RTNETADDRIPV4& networkMask):
+      ConfigEntity(name, cfg, criteria, 5),
+      m_NetworkID(networkID),
+      m_NetworkMask(networkMask)
+    {
+        m_UpperIP.u = m_NetworkID.u | (~m_NetworkMask.u);
+        m_LowerIP.u = m_NetworkID.u;
+    };
+
+    const RTNETADDRIPV4& upperIp() const {return m_UpperIP;}
+    const RTNETADDRIPV4& lowerIp() const {return m_LowerIP;}
+    const RTNETADDRIPV4& networkId() const {return m_NetworkID;}
+    const RTNETADDRIPV4& netmask() const {return m_NetworkMask;}
+
+    private:
+    RTNETADDRIPV4 m_NetworkID;
+    RTNETADDRIPV4 m_NetworkMask;
+    RTNETADDRIPV4 m_UpperIP;
+    RTNETADDRIPV4 m_LowerIP;
+};
+
+
+/**
+ * Host specific entry
+ * Address pool is contains one element
+ */
+class HostConfigEntity: public NetworkConfigEntity
+{
+public:
+    HostConfigEntity(const RTNETADDRIPV4& addr,
+                     std::string name,
+                     const NetworkConfigEntity *cfg,
+                     const ClientMatchCriteria *criteria):
+      NetworkConfigEntity(name,
+                          static_cast<const ConfigEntity*>(cfg), criteria, 10,
+                          cfg->networkId(), cfg->netmask(), addr, addr)
+    {
+        /* upper addr == lower addr */
+    }
+};
+
+class RootConfigEntity: public NetworkConfigEntity
+{
+public:
+    RootConfigEntity(std::string name, uint32_t expirationPeriod);
+    virtual ~RootConfigEntity(){};
+};
+
+
+#if 0
+/**
+ * Shared regions e.g. some of configured networks declarations
+ * are cover each other.
+ * XXX: Shared Network is join on Network config entities with possible
+ * overlaps in address pools. for a moment we won't configure and use them them
+ */
+class SharedNetworkConfigEntity: public NetworkEntity
+{
+public:
+    SharedNetworkConfigEntity(){}
+    int match(const Client& client) const { return m_criteria.match(client)? 3 : 0;}
+
+    SharedNetworkConfigEntity(NetworkEntity& network)
+    {
+        Networks.push_back(network);
+    }
+    virtual ~SharedNetworkConfigEntity(){}
+
+    std::vector<NetworkConfigEntity> Networks;
+};
+#endif
+
+class ConfigurationManager
+{
+public:
+    static ConfigurationManager* getConfigurationManager();
+    static int extractRequestList(PCRTNETBOOTP pDhcpMsg, size_t cbDhcpMsg, RawOption& rawOpt);
+
+    int loadFromFile(const com::Utf8Str&);
+    int saveToFile();
+    /**
+     *
+     */
+    Client getClientByDhcpPacket(const RTNETBOOTP *pDhcpMsg, size_t cbDhcpMsg);
+
+    /**
+     * XXX: it's could be done on DHCPOFFER or on DHCPACK (rfc2131 gives freedom here
+     * 3.1.2, what is strict that allocation should do address check before real
+     * allocation)...
+     */
+    Lease allocateLease4Client(const Client& client, PCRTNETBOOTP pDhcpMsg, size_t cbDhcpMsg);
+
+    /**
+     * We call this before DHCPACK sent and after DHCPREQUEST received ...
+     * when requested configuration is acceptable.
+     */
+    int commitLease4Client(Client& client);
+
+    /**
+     * Expires client lease.
+     */
+    int expireLease4Client(Client& client);
+
+    static int findOption(uint8_t uOption, PCRTNETBOOTP pDhcpMsg, size_t cbDhcpMsg, RawOption& opt);
+
+    NetworkConfigEntity *addNetwork(NetworkConfigEntity *pCfg,
+                                    const RTNETADDRIPV4& networkId,
+                                    const RTNETADDRIPV4& netmask,
+                                    RTNETADDRIPV4& UpperAddress,
+                                    RTNETADDRIPV4& LowerAddress);
+
+    HostConfigEntity *addHost(NetworkConfigEntity*, const RTNETADDRIPV4&, ClientMatchCriteria*);
+    int addToAddressList(uint8_t u8OptId, RTNETADDRIPV4& address);
+    int flushAddressList(uint8_t u8OptId);
+    int setString(uint8_t u8OptId, const std::string& str);
+    const std::string& getString(uint8_t u8OptId);
+    const Ipv4AddressContainer& getAddressList(uint8_t u8OptId);
+
+private:
+    ConfigurationManager():m(NULL){}
+    void init();
+
+    ~ConfigurationManager();
+    bool isAddressTaken(const RTNETADDRIPV4& addr, Lease& lease);
+    bool isAddressTaken(const RTNETADDRIPV4& addr);
+
+public:
+    /* nulls */
+    const Ipv4AddressContainer m_empty;
+    const std::string    m_noString;
+
+private:
+    struct Data;
+    Data *m;
+};
+
+
+class NetworkManager
+{
+public:
+    static NetworkManager *getNetworkManager(ComPtr<IDHCPServer> aDhcpServer = ComPtr<IDHCPServer>());
+
+    const RTNETADDRIPV4& getOurAddress() const;
+    const RTNETADDRIPV4& getOurNetmask() const;
+    const RTMAC& getOurMac() const;
+
+    void setOurAddress(const RTNETADDRIPV4& aAddress);
+    void setOurNetmask(const RTNETADDRIPV4& aNetmask);
+    void setOurMac(const RTMAC& aMac);
+
+    bool handleDhcpReqDiscover(PCRTNETBOOTP pDhcpMsg, size_t cb);
+    bool handleDhcpReqRequest(PCRTNETBOOTP pDhcpMsg, size_t cb);
+    bool handleDhcpReqDecline(PCRTNETBOOTP pDhcpMsg, size_t cb);
+    bool handleDhcpReqRelease(PCRTNETBOOTP pDhcpMsg, size_t cb);
+
+    void setService(const VBoxNetHlpUDPService *);
+private:
+    NetworkManager();
+    ~NetworkManager();
+
+    int offer4Client(const Client& lease, uint32_t u32Xid, uint8_t *pu8ReqList, int cReqList);
+    int ack(const Client& lease, uint32_t u32Xid, uint8_t *pu8ReqList, int cReqList);
+    int nak(const Client& lease, uint32_t u32Xid);
+
+    int prepareReplyPacket4Client(const Client& client, uint32_t u32Xid);
+    int doReply(const Client& client, const std::vector<RawOption>& extra);
+    int processParameterReqList(const Client& client, const uint8_t *pu8ReqList, int cReqList, std::vector<RawOption>& extra);
+
+private:
+    static NetworkManager *g_NetworkManager;
+
+private:
+    struct Data;
+    Data *m;
+
+};
+
+
+extern const ClientMatchCriteria *g_AnyClient;
+extern RootConfigEntity *g_RootConfig;
+extern const NullConfigEntity *g_NullConfig;
+
+/**
+ * Helper class for stuffing DHCP options into a reply packet.
+ */
+class VBoxNetDhcpWriteCursor
+{
+private:
+    uint8_t        *m_pbCur;       /**< The current cursor position. */
+    uint8_t        *m_pbEnd;       /**< The end the current option space. */
+    uint8_t        *m_pfOverload;  /**< Pointer to the flags of the overload option. */
+    uint8_t         m_fUsed;       /**< Overload fields that have been used. */
+    PRTNETDHCPOPT   m_pOpt;        /**< The current option. */
+    PRTNETBOOTP     m_pDhcp;       /**< The DHCP packet. */
+    bool            m_fOverflowed; /**< Set if we've overflowed, otherwise false. */
+
+public:
+    /** Instantiate an option cursor for the specified DHCP message. */
+    VBoxNetDhcpWriteCursor(PRTNETBOOTP pDhcp, size_t cbDhcp) :
+        m_pbCur(&pDhcp->bp_vend.Dhcp.dhcp_opts[0]),
+        m_pbEnd((uint8_t *)pDhcp + cbDhcp),
+        m_pfOverload(NULL),
+        m_fUsed(0),
+        m_pOpt(NULL),
+        m_pDhcp(pDhcp),
+        m_fOverflowed(false)
+    {
+        AssertPtr(pDhcp);
+        Assert(cbDhcp > RT_UOFFSETOF(RTNETBOOTP, bp_vend.Dhcp.dhcp_opts[10]));
+    }
+
+    /** Destructor.  */
+    ~VBoxNetDhcpWriteCursor()
+    {
+        m_pbCur = m_pbEnd = m_pfOverload = NULL;
+        m_pOpt = NULL;
+        m_pDhcp = NULL;
+    }
+
+    /**
+     * Try use the bp_file field.
+     * @returns true if not overloaded, false otherwise.
+     */
+    bool useBpFile(void)
+    {
+        if (    m_pfOverload
+            &&  (*m_pfOverload & 1))
+            return false;
+        m_fUsed |= 1 /* bp_file flag*/;
+        return true;
+    }
+
+
+    /**
+     * Try overload more BOOTP fields
+     */
+    bool overloadMore(void)
+    {
+        /* switch option area. */
+        uint8_t    *pbNew;
+        uint8_t    *pbNewEnd;
+        uint8_t     fField;
+        if (!(m_fUsed & 1))
+        {
+            fField     = 1;
+            pbNew      = &m_pDhcp->bp_file[0];
+            pbNewEnd   = &m_pDhcp->bp_file[sizeof(m_pDhcp->bp_file)];
+        }
+        else if (!(m_fUsed & 2))
+        {
+            fField     = 2;
+            pbNew      = &m_pDhcp->bp_sname[0];
+            pbNewEnd   = &m_pDhcp->bp_sname[sizeof(m_pDhcp->bp_sname)];
+        }
+        else
+            return false;
+
+        if (!m_pfOverload)
+        {
+            /* Add an overload option. */
+            *m_pbCur++ = RTNET_DHCP_OPT_OPTION_OVERLOAD;
+            *m_pbCur++ = fField;
+            m_pfOverload = m_pbCur;
+            *m_pbCur++ = 1;     /* bp_file flag */
+        }
+        else
+            *m_pfOverload |= fField;
+
+        /* pad current option field */
+        while (m_pbCur != m_pbEnd)
+            *m_pbCur++ = RTNET_DHCP_OPT_PAD; /** @todo not sure if this stuff is at all correct... */
+
+        /* switch */
+        m_pbCur = pbNew;
+        m_pbEnd = pbNewEnd;
+        return true;
+    }
+
+    /**
+     * Begin an option.
+     *
+     * @returns true on success, false if we're out of space.
+     *
+     * @param   uOption     The option number.
+     * @param   cb          The amount of data.
+     */
+    bool begin(uint8_t uOption, size_t cb)
+    {
+        /* Check that the data of the previous option has all been written. */
+        Assert(   !m_pOpt
+               || (m_pbCur - m_pOpt->dhcp_len == (uint8_t *)(m_pOpt + 1)));
+        AssertMsg(cb <= 255, ("%#x\n", cb));
+
+        /* Check if we need to overload more stuff. */
+        if ((uintptr_t)(m_pbEnd - m_pbCur) < cb + 2 + (m_pfOverload ? 1 : 3))
+        {
+            m_pOpt = NULL;
+            if (!overloadMore())
+            {
+                m_fOverflowed = true;
+                AssertMsgFailedReturn(("%u %#x\n", uOption, cb), false);
+            }
+            if ((uintptr_t)(m_pbEnd - m_pbCur) < cb + 2 + 1)
+            {
+                m_fOverflowed = true;
+                AssertMsgFailedReturn(("%u %#x\n", uOption, cb), false);
+            }
+        }
+
+        /* Emit the option header. */
+        m_pOpt = (PRTNETDHCPOPT)m_pbCur;
+        m_pOpt->dhcp_opt = uOption;
+        m_pOpt->dhcp_len = (uint8_t)cb;
+        m_pbCur += 2;
+        return true;
+    }
+
+    /**
+     * Puts option data.
+     *
+     * @param   pvData      The data.
+     * @param   cb          The amount to put.
+     */
+    void put(void const *pvData, size_t cb)
+    {
+        Assert(m_pOpt || m_fOverflowed);
+        if (RT_LIKELY(m_pOpt))
+        {
+            Assert((uintptr_t)m_pbCur - (uintptr_t)(m_pOpt + 1) + cb  <= (size_t)m_pOpt->dhcp_len);
+            memcpy(m_pbCur, pvData, cb);
+            m_pbCur += cb;
+        }
+    }
+
+    /**
+     * Puts an IPv4 Address.
+     *
+     * @param   IPv4Addr    The address.
+     */
+    void putIPv4Addr(RTNETADDRIPV4 IPv4Addr)
+    {
+        put(&IPv4Addr, 4);
+    }
+
+    /**
+     * Adds an IPv4 address option.
+     *
+     * @returns true/false just like begin().
+     *
+     * @param   uOption     The option number.
+     * @param   IPv4Addr    The address.
+     */
+    bool optIPv4Addr(uint8_t uOption, RTNETADDRIPV4 IPv4Addr)
+    {
+        if (!begin(uOption, 4))
+            return false;
+        putIPv4Addr(IPv4Addr);
+        return true;
+    }
+
+    /**
+     * Adds an option taking 1 or more IPv4 address.
+     *
+     * If the vector contains no addresses, the option will not be added.
+     *
+     * @returns true/false just like begin().
+     *
+     * @param   uOption     The option number.
+     * @param   rIPv4Addrs  Reference to the address vector.
+     */
+    bool optIPv4Addrs(uint8_t uOption, std::vector<RTNETADDRIPV4> const &rIPv4Addrs)
+    {
+        size_t const c = rIPv4Addrs.size();
+        if (!c)
+            return true;
+
+        if (!begin(uOption, 4*c))
+            return false;
+        for (size_t i = 0; i < c; i++)
+            putIPv4Addr(rIPv4Addrs[i]);
+        return true;
+    }
+
+    /**
+     * Puts an 8-bit integer.
+     *
+     * @param   u8          The integer.
+     */
+    void putU8(uint8_t u8)
+    {
+        put(&u8, 1);
+    }
+
+    /**
+     * Adds an 8-bit integer option.
+     *
+     * @returns true/false just like begin().
+     *
+     * @param   uOption     The option number.
+     * @param   u8          The integer
+     */
+    bool optU8(uint8_t uOption, uint8_t u8)
+    {
+        if (!begin(uOption, 1))
+            return false;
+        putU8(u8);
+        return true;
+    }
+
+    /**
+     * Puts an 32-bit integer (network endian).
+     *
+     * @param   u32         The integer.
+     */
+    void putU32(uint32_t u32)
+    {
+        put(&u32, 4);
+    }
+
+    /**
+     * Adds an 32-bit integer (network endian) option.
+     *
+     * @returns true/false just like begin().
+     *
+     * @param   uOption     The option number.
+     * @param   u32         The integer.
+     */
+    bool optU32(uint8_t uOption, uint32_t u32)
+    {
+        if (!begin(uOption, 4))
+            return false;
+        putU32(u32);
+        return true;
+    }
+
+    /**
+     * Puts a std::string.
+     *
+     * @param   rStr        Reference to the string.
+     */
+    void putStr(std::string const &rStr)
+    {
+        put(rStr.c_str(), rStr.size());
+    }
+
+    /**
+     * Adds an std::string option if the string isn't empty.
+     *
+     * @returns true/false just like begin().
+     *
+     * @param   uOption     The option number.
+     * @param   rStr        Reference to the string.
+     */
+    bool optStr(uint8_t uOption, std::string const &rStr)
+    {
+        const size_t cch = rStr.size();
+        if (!cch)
+            return true;
+
+        if (!begin(uOption, cch))
+            return false;
+        put(rStr.c_str(), cch);
+        return true;
+    }
+
+    /**
+     * Whether we've overflowed.
+     *
+     * @returns true on overflow, false otherwise.
+     */
+    bool hasOverflowed(void) const
+    {
+        return m_fOverflowed;
+    }
+
+    /**
+     * Adds the terminating END option.
+     *
+     * The END will always be added as we're reserving room for it, however, we
+     * might have dropped previous options due to overflows and that is what the
+     * return status indicates.
+     *
+     * @returns true on success, false on a (previous) overflow.
+     */
+    bool optEnd(void)
+    {
+        Assert((uintptr_t)(m_pbEnd - m_pbCur) < 4096);
+        *m_pbCur++ = RTNET_DHCP_OPT_END;
+        return !hasOverflowed();
+    }
+};
+
+#endif /* !VBOX_INCLUDED_SRC_DHCP_Config_h */
diff --git a/src/VBox/NetworkServices/DHCP/Makefile.kmk b/src/VBox/NetworkServices/DHCP/Makefile.kmk
new file mode 100644
index 00000000..41e9bb8e
--- /dev/null
+++ b/src/VBox/NetworkServices/DHCP/Makefile.kmk
@@ -0,0 +1,72 @@
+ # $Id: Makefile.kmk $
+## @file
+# Sub-Makefile for VBoxNetDHCP.
+#
+
+#
+# Copyright (C) 2009-2019 Oracle Corporation
+#
+# This file is part of VirtualBox Open Source Edition (OSE), as
+# available from http://www.virtualbox.org. This file is free software;
+# you can redistribute it and/or modify it under the terms of the GNU
+# General Public License (GPL) as published by the Free Software
+# Foundation, in version 2 as it comes in the "COPYING" file of the
+# VirtualBox OSE distribution. VirtualBox OSE is distributed in the
+# hope that it will be useful, but WITHOUT ANY WARRANTY of any kind.
+#
+
+SUB_DEPTH = ../../../..
+include $(KBUILD_PATH)/subheader.kmk
+
+VBOX_PATH_NET_DHCP_SRC := $(PATH_SUB_CURRENT)
+
+#
+# Targets.
+#
+ifdef VBOX_WITH_HARDENING
+ PROGRAMS += VBoxNetDHCPHardened
+ DLLS += VBoxNetDHCP
+else
+ PROGRAMS += VBoxNetDHCP
+endif
+
+
+#
+# Hardened VBoxNetDHCP.
+#
+VBoxNetDHCPHardened_TEMPLATE = VBOXR3HARDENEDEXE
+VBoxNetDHCPHardened_SOURCES = VBoxNetDHCPHardened.cpp
+VBoxNetDHCPHardened_SOURCES.win = $(VBoxNetDHCP_0_OUTDIR)/VBoxNetDHCP-icon.rc
+VBoxNetDHCPHardened_NAME = VBoxNetDHCP
+VBoxNetDHCPHardened_LDFLAGS.win = /SUBSYSTEM:windows
+
+
+#
+# VBoxNetDHCP
+#
+VBoxNetDHCP_TEMPLATE := VBOX$(if-expr defined(VBOX_WITH_HARDENING),MAINDLL,MAINCLIENTEXE)
+VBoxNetDHCP_SOURCES = \
+	VBoxNetDHCP.cpp \
+	Config.cpp \
+	NetworkManagerDhcp.cpp \
+	$(VBOX_PATH_NET_DHCP_SRC)/../NetLib/VBoxNetIntIf.cpp \
+	$(VBOX_PATH_NET_DHCP_SRC)/../NetLib/VBoxNetUDP.cpp \
+	$(VBOX_PATH_NET_DHCP_SRC)/../NetLib/VBoxNetARP.cpp \
+	$(VBOX_PATH_NET_DHCP_SRC)/../NetLib/VBoxNetBaseService.cpp \
+	$(VBOX_PATH_NET_DHCP_SRC)/../NetLib/ComHostUtils.cpp
+VBoxNetDHCP_LIBS = \
+	$(LIB_RUNTIME)
+VBoxNetDHCP_LDFLAGS.win = /SUBSYSTEM:windows
+
+ifeq ($(KBUILD_TARGET),win)
+# Icon include file.
+VBoxNetDHCP_SOURCES     += VBoxNetDHCP.rc
+VBoxNetDHCP.rc_INCS      = $(VBoxNetDHCP_0_OUTDIR)
+VBoxNetDHCP.rc_DEPS      = $(VBoxNetDHCP_0_OUTDIR)/VBoxNetDHCP-icon.rc
+VBoxNetDHCP.rc_CLEAN     = $(VBoxNetDHCP_0_OUTDIR)/VBoxNetDHCP-icon.rc
+$$(VBoxNetDHCP_0_OUTDIR)/VBoxNetDHCP-icon.rc: $(VBOX_WINDOWS_ICON_FILE) $$(VBoxNetDHCP_DEFPATH)/Makefile.kmk | $$(dir $$@)
+	$(RM) -f $@
+	$(APPEND) $@ 'IDI_VIRTUALBOX ICON DISCARDABLE "$(subst /,\\,$(VBOX_WINDOWS_ICON_FILE))"'
+endif # win
+
+include $(FILE_KBUILD_SUB_FOOTER)
diff --git a/src/VBox/NetworkServices/DHCP/NetworkManagerDhcp.cpp b/src/VBox/NetworkServices/DHCP/NetworkManagerDhcp.cpp
new file mode 100644
index 00000000..591da5b8
--- /dev/null
+++ b/src/VBox/NetworkServices/DHCP/NetworkManagerDhcp.cpp
@@ -0,0 +1,189 @@
+/* $Id: NetworkManagerDhcp.cpp $ */
+/** @file
+ * NetworkManagerDhcp - Network Manager part handling Dhcp.
+ */
+
+/*
+ * Copyright (C) 2013-2019 Oracle Corporation
+ *
+ * This file is part of VirtualBox Open Source Edition (OSE), as
+ * available from http://www.virtualbox.org. This file is free software;
+ * you can redistribute it and/or modify it under the terms of the GNU
+ * General Public License (GPL) as published by the Free Software
+ * Foundation, in version 2 as it comes in the "COPYING" file of the
+ * VirtualBox OSE distribution. VirtualBox OSE is distributed in the
+ * hope that it will be useful, but WITHOUT ANY WARRANTY of any kind.
+ */
+
+
+/*********************************************************************************************************************************
+*   Header Files                                                                                                                 *
+*********************************************************************************************************************************/
+#include <iprt/asm.h>
+#include <iprt/cdefs.h>
+#include <iprt/getopt.h>
+#include <iprt/net.h>
+#include <iprt/param.h>
+#include <iprt/path.h>
+#include <iprt/stream.h>
+#include <iprt/time.h>
+#include <iprt/string.h>
+
+#include "../NetLib/shared_ptr.h"
+
+#include <vector>
+#include <list>
+#include <string>
+#include <map>
+
+#include <VBox/sup.h>
+#include <VBox/intnet.h>
+
+#define BASE_SERVICES_ONLY
+#include "../NetLib/VBoxNetBaseService.h"
+#include "Config.h"
+#include "ClientDataInt.h"
+
+/**
+ * The client is requesting an offer.
+ *
+ * @returns true.
+ *
+ * @param   pDhcpMsg    The message.
+ * @param   cb          The message size.
+ */
+bool NetworkManager::handleDhcpReqDiscover(PCRTNETBOOTP pDhcpMsg, size_t cb)
+{
+    RawOption opt;
+    RT_ZERO(opt);
+
+    /* 1. Find client */
+    ConfigurationManager *confManager = ConfigurationManager::getConfigurationManager();
+    Client client = confManager->getClientByDhcpPacket(pDhcpMsg, cb);
+
+    /* 2. Find/Bind lease for client */
+    Lease lease = confManager->allocateLease4Client(client, pDhcpMsg, cb);
+    AssertReturn(lease != Lease::NullLease, VINF_SUCCESS);
+
+    int rc = ConfigurationManager::extractRequestList(pDhcpMsg, cb, opt);
+    NOREF(rc); /** @todo check */
+
+    /* 3. Send of offer */
+
+    lease.bindingPhase(true);
+    lease.phaseStart(RTTimeMilliTS());
+    lease.setExpiration(300); /* 3 min. */
+    offer4Client(client, pDhcpMsg->bp_xid, opt.au8RawOpt, opt.cbRawOpt);
+
+    return true;
+}
+
+
+/**
+ * The client is requesting an offer.
+ *
+ * @returns true.
+ *
+ * @param   pDhcpMsg    The message.
+ * @param   cb          The message size.
+ */
+bool NetworkManager::handleDhcpReqRequest(PCRTNETBOOTP pDhcpMsg, size_t cb)
+{
+    ConfigurationManager *confManager = ConfigurationManager::getConfigurationManager();
+
+    /* 1. find client */
+    Client client = confManager->getClientByDhcpPacket(pDhcpMsg, cb);
+
+    /* 2. find bound lease */
+    Lease l = client.lease();
+    if (l != Lease::NullLease)
+    {
+
+        if (l.isExpired())
+        {
+            /* send client to INIT state */
+            Client c(client);
+            nak(client, pDhcpMsg->bp_xid);
+            confManager->expireLease4Client(c);
+            return true;
+        }
+        /* XXX: Validate request */
+        RawOption opt;
+        RT_ZERO(opt);
+
+        Client c(client);
+        int rc = confManager->commitLease4Client(c);
+        AssertRCReturn(rc, false);
+
+        rc = ConfigurationManager::extractRequestList(pDhcpMsg, cb, opt);
+        AssertRCReturn(rc, false);
+
+        ack(client, pDhcpMsg->bp_xid, opt.au8RawOpt, opt.cbRawOpt);
+    }
+    else
+    {
+        nak(client, pDhcpMsg->bp_xid);
+    }
+    return true;
+}
+
+
+/**
+ * The client is declining an offer we've made.
+ *
+ * @returns true.
+ *
+ * @param   pDhcpMsg    The message.
+ * @param   cb          The message size.
+ */
+bool NetworkManager::handleDhcpReqDecline(PCRTNETBOOTP, size_t)
+{
+    /** @todo Probably need to match the server IP here to work correctly with
+     *        other servers. */
+
+    /*
+     * The client is supposed to pass us option 50, requested address,
+     * from the offer. We also match the lease state. Apparently the
+     * MAC address is not supposed to be checked here.
+     */
+
+    /** @todo this is not required in the initial implementation, do it later. */
+    return true;
+}
+
+
+/**
+ * The client is releasing its lease - good boy.
+ *
+ * @returns true.
+ *
+ * @param   pDhcpMsg    The message.
+ * @param   cb          The message size.
+ */
+bool NetworkManager::handleDhcpReqRelease(PCRTNETBOOTP, size_t)
+{
+    /** @todo Probably need to match the server IP here to work correctly with
+     *        other servers. */
+
+    /*
+     * The client may pass us option 61, client identifier, which we should
+     * use to find the lease by.
+     *
+     * We're matching MAC address and lease state as well.
+     */
+
+    /*
+     * If no client identifier or if we couldn't find a lease by using it,
+     * we will try look it up by the client IP address.
+     */
+
+
+    /*
+     * If found, release it.
+     */
+
+
+    /** @todo this is not required in the initial implementation, do it later. */
+    return true;
+}
+
diff --git a/src/VBox/NetworkServices/DHCP/README.customoptions b/src/VBox/NetworkServices/DHCP/README.customoptions
new file mode 100644
index 00000000..c121d318
--- /dev/null
+++ b/src/VBox/NetworkServices/DHCP/README.customoptions
@@ -0,0 +1,23 @@
+To configure custom DHCP options for a VM use the following command adapted
+to your needs:
+
+$ VBoxManage dhcpserver modify \
+    --netname test-0 --options --vm "Test Client" --slot 0 \
+    --id 0 --value "224=c0:a8:02:01:c0:a8:02:02" \
+    --id 0 --value "225=0:0"
+
+Note that custom DHCP options must be specified with ID 0 and the actual
+number in the value. This has technical reasons which may change in future
+VirtualBox releases.
+
+
+It corresponds to the following bit of ISC 'dhcpd.conf':
+
+option sample1 code 224 = array of ip-address;
+option sample2 code 225 = array of integer 8;
+
+...
+    option sample1 192.168.2.1,192.168.2.2;
+    option sample2 0,0;
+...
+
diff --git a/src/VBox/NetworkServices/DHCP/VBoxNetDHCP.cpp b/src/VBox/NetworkServices/DHCP/VBoxNetDHCP.cpp
new file mode 100644
index 00000000..8c543272
--- /dev/null
+++ b/src/VBox/NetworkServices/DHCP/VBoxNetDHCP.cpp
@@ -0,0 +1,885 @@
+/* $Id: VBoxNetDHCP.cpp $ */
+/** @file
+ * VBoxNetDHCP - DHCP Service for connecting to IntNet.
+ */
+
+/*
+ * Copyright (C) 2009-2019 Oracle Corporation
+ *
+ * This file is part of VirtualBox Open Source Edition (OSE), as
+ * available from http://www.virtualbox.org. This file is free software;
+ * you can redistribute it and/or modify it under the terms of the GNU
+ * General Public License (GPL) as published by the Free Software
+ * Foundation, in version 2 as it comes in the "COPYING" file of the
+ * VirtualBox OSE distribution. VirtualBox OSE is distributed in the
+ * hope that it will be useful, but WITHOUT ANY WARRANTY of any kind.
+ */
+
+/** @page pg_net_dhcp       VBoxNetDHCP
+ *
+ * Write a few words...
+ *
+ */
+
+
+/*********************************************************************************************************************************
+*   Header Files                                                                                                                 *
+*********************************************************************************************************************************/
+#include <VBox/com/com.h>
+#include <VBox/com/listeners.h>
+#include <VBox/com/string.h>
+#include <VBox/com/Guid.h>
+#include <VBox/com/array.h>
+#include <VBox/com/ErrorInfo.h>
+#include <VBox/com/errorprint.h>
+#include <VBox/com/EventQueue.h>
+#include <VBox/com/VirtualBox.h>
+
+#include <iprt/alloca.h>
+#include <iprt/buildconfig.h>
+#include <iprt/err.h>
+#include <iprt/net.h>                   /* must come before getopt */
+#include <iprt/getopt.h>
+#include <iprt/initterm.h>
+#include <iprt/message.h>
+#include <iprt/param.h>
+#include <iprt/path.h>
+#include <iprt/stream.h>
+#include <iprt/time.h>
+#include <iprt/string.h>
+#ifdef RT_OS_WINDOWS
+# include <iprt/thread.h>
+#endif
+
+#include <VBox/sup.h>
+#include <VBox/intnet.h>
+#include <VBox/intnetinline.h>
+#include <VBox/vmm/vmm.h>
+#include <VBox/version.h>
+
+#include "../NetLib/VBoxNetLib.h"
+#include "../NetLib/shared_ptr.h"
+
+#include <vector>
+#include <list>
+#include <string>
+#include <map>
+
+#include "../NetLib/VBoxNetBaseService.h"
+#include "../NetLib/utils.h"
+
+#ifdef RT_OS_WINDOWS /* WinMain */
+# include <iprt/win/windows.h>
+# include <stdlib.h>
+# ifdef INET_ADDRSTRLEN
+/* On Windows INET_ADDRSTRLEN defined as 22 Ws2ipdef.h, because it include port number */
+#  undef INET_ADDRSTRLEN
+# endif
+# define INET_ADDRSTRLEN 16
+#else
+# include <netinet/in.h>
+#endif
+
+
+#include "Config.h"
+
+
+/*********************************************************************************************************************************
+*   Structures and Typedefs                                                                                                      *
+*********************************************************************************************************************************/
+/**
+ * DHCP server instance.
+ */
+class VBoxNetDhcp : public VBoxNetBaseService, public NATNetworkEventAdapter
+{
+public:
+    VBoxNetDhcp();
+    virtual ~VBoxNetDhcp();
+
+    int                 init();
+    void                done();
+    void                usage(void) { /* XXX: document options */ };
+    int                 parseOpt(int rc, const RTGETOPTUNION& getOptVal);
+    int                 processFrame(void *, size_t) {return VERR_IGNORED; };
+    int                 processGSO(PCPDMNETWORKGSO, size_t) {return VERR_IGNORED; };
+    int                 processUDP(void *, size_t);
+
+protected:
+    bool                handleDhcpMsg(uint8_t uMsgType, PCRTNETBOOTP pDhcpMsg, size_t cb);
+
+    void                debugPrintV(int32_t iMinLevel, bool fMsg,  const char *pszFmt, va_list va) const;
+    static const char  *debugDhcpName(uint8_t uMsgType);
+
+private:
+    int initNoMain();
+    int initWithMain();
+    HRESULT HandleEvent(VBoxEventType_T aEventType, IEvent *pEvent);
+
+    static int hostDnsServers(const ComHostPtr& host,
+                              const RTNETADDRIPV4& networkid,
+                              const AddressToOffsetMapping& mapping,
+                              AddressList& servers);
+    int fetchAndUpdateDnsInfo();
+
+protected:
+    /** @name The DHCP server specific configuration data members.
+     * @{ */
+    /*
+     * XXX: what was the plan? SQL3 or plain text file?
+     * How it will coexists with managment from VBoxManagement, who should manage db
+     * in that case (VBoxManage, VBoxSVC ???)
+     */
+    std::string         m_LeaseDBName;
+
+    /** @} */
+
+    /* corresponding dhcp server description in Main */
+    ComPtr<IDHCPServer> m_DhcpServer;
+
+    ComPtr<INATNetwork> m_NATNetwork;
+
+    /** Listener for Host DNS changes */
+    ComNatListenerPtr m_VBoxListener;
+    ComNatListenerPtr m_VBoxClientListener;
+
+    NetworkManager *m_NetworkManager;
+
+    /*
+     * We will ignore cmd line parameters IFF there will be some DHCP specific arguments
+     * otherwise all paramters will come from Main.
+     */
+    bool m_fIgnoreCmdLineParameters;
+
+    /*
+     * -b -n 10.0.1.2 -m 255.255.255.0 -> to the list processing in
+     */
+    typedef struct
+    {
+        char Key;
+        std::string strValue;
+    } CMDLNPRM;
+    std::list<CMDLNPRM> CmdParameterll;
+    typedef std::list<CMDLNPRM>::iterator CmdParameterIterator;
+
+    /** @name Debug stuff
+     * @{  */
+    int32_t             m_cVerbosity;
+    uint8_t             m_uCurMsgType;
+    size_t              m_cbCurMsg;
+    PCRTNETBOOTP        m_pCurMsg;
+    VBOXNETUDPHDRS      m_CurHdrs;
+    /** @} */
+};
+
+
+static inline int configGetBoundryAddress(const ComDhcpServerPtr& dhcp, bool fUpperBoundry, RTNETADDRIPV4& boundryAddress)
+{
+    boundryAddress.u = INADDR_ANY;
+
+    HRESULT hrc;
+    com::Bstr strAddress;
+    if (fUpperBoundry)
+        hrc = dhcp->COMGETTER(UpperIP)(strAddress.asOutParam());
+    else
+        hrc = dhcp->COMGETTER(LowerIP)(strAddress.asOutParam());
+    AssertComRCReturn(hrc, VERR_INTERNAL_ERROR);
+
+    return RTNetStrToIPv4Addr(com::Utf8Str(strAddress).c_str(), &boundryAddress);
+}
+
+
+/*********************************************************************************************************************************
+*   Global Variables                                                                                                             *
+*********************************************************************************************************************************/
+/** Pointer to the DHCP server. */
+static VBoxNetDhcp *g_pDhcp;
+
+/* DHCP server specific options */
+static RTGETOPTDEF g_aOptionDefs[] =
+{
+  { "--lease-db",       'D',   RTGETOPT_REQ_STRING },
+  { "--begin-config",   'b',   RTGETOPT_REQ_NOTHING },
+  { "--gateway",        'g',   RTGETOPT_REQ_IPV4ADDR },
+  { "--lower-ip",       'l',   RTGETOPT_REQ_IPV4ADDR },
+  { "--upper-ip",       'u',   RTGETOPT_REQ_IPV4ADDR },
+};
+
+/**
+ * Construct a DHCP server with a default configuration.
+ */
+VBoxNetDhcp::VBoxNetDhcp()
+  : VBoxNetBaseService("VBoxNetDhcp", "VBoxNetDhcp"),
+    m_NetworkManager(NULL)
+{
+    /*   m_enmTrunkType          = kIntNetTrunkType_WhateverNone; */
+    RTMAC mac;
+    mac.au8[0]     = 0x08;
+    mac.au8[1]     = 0x00;
+    mac.au8[2]     = 0x27;
+    mac.au8[3]     = 0x40;
+    mac.au8[4]     = 0x41;
+    mac.au8[5]     = 0x42;
+    setMacAddress(mac);
+
+    RTNETADDRIPV4 address;
+    address.u = RT_H2N_U32_C(RT_BSWAP_U32_C(RT_MAKE_U32_FROM_U8( 10,  0,  2,  5)));
+    setIpv4Address(address);
+
+    setSendBufSize(8 * _1K);
+    setRecvBufSize(50 * _1K);
+
+    m_uCurMsgType           = UINT8_MAX;
+    m_cbCurMsg              = 0;
+    m_pCurMsg               = NULL;
+    RT_ZERO(m_CurHdrs);
+
+    m_fIgnoreCmdLineParameters = true;
+
+    for(unsigned int i = 0; i < RT_ELEMENTS(g_aOptionDefs); ++i)
+        addCommandLineOption(&g_aOptionDefs[i]);
+}
+
+
+/**
+ * Destruct a DHCP server.
+ */
+VBoxNetDhcp::~VBoxNetDhcp()
+{
+}
+
+
+
+
+/**
+ * Parse the DHCP specific arguments.
+ *
+ * This callback caled for each paramenter so
+ * ....
+ * we nee post analisys of the parameters, at least
+ *    for -b, -g, -l, -u, -m
+ */
+int VBoxNetDhcp::parseOpt(int rc, const RTGETOPTUNION& Val)
+{
+    CMDLNPRM prm;
+
+    /* Ok, we've entered here, thus we can't ignore cmd line parameters anymore */
+    m_fIgnoreCmdLineParameters = false;
+
+    prm.Key = rc;
+
+    switch (rc)
+    {
+        case 'l':
+        case 'u':
+        case 'g':
+        {
+            char buf[17];
+            RTStrPrintf(buf, 17, "%RTnaipv4", Val.IPv4Addr.u);
+            prm.strValue = buf;
+            CmdParameterll.push_back(prm);
+        }
+        break;
+
+        case 'b': // ignore
+        case 'D': // ignore
+            break;
+
+        default:
+            rc = RTGetOptPrintError(rc, &Val);
+            RTPrintf("Use --help for more information.\n");
+            return rc;
+    }
+
+    return VINF_SUCCESS;
+}
+
+int VBoxNetDhcp::init()
+{
+    int rc = this->VBoxNetBaseService::init();
+    AssertRCReturn(rc, rc);
+
+    if (isMainNeeded())
+        rc = initWithMain();
+    else
+        rc = initNoMain();
+    AssertRCReturn(rc, rc);
+
+    m_NetworkManager = NetworkManager::getNetworkManager(m_DhcpServer);
+    AssertPtrReturn(m_NetworkManager, VERR_INTERNAL_ERROR);
+
+    m_NetworkManager->setOurAddress(getIpv4Address());
+    m_NetworkManager->setOurNetmask(getIpv4Netmask());
+    m_NetworkManager->setOurMac(getMacAddress());
+    m_NetworkManager->setService(this);
+
+    return VINF_SUCCESS;
+}
+
+void VBoxNetDhcp::done()
+{
+    destroyNatListener(m_VBoxListener, virtualbox);
+    destroyClientListener(m_VBoxClientListener, virtualboxClient);
+}
+
+int  VBoxNetDhcp::processUDP(void *pv, size_t cbPv)
+{
+    PCRTNETBOOTP pDhcpMsg = (PCRTNETBOOTP)pv;
+    m_pCurMsg  = pDhcpMsg;
+    m_cbCurMsg = cbPv;
+
+    uint8_t uMsgType;
+    if (RTNetIPv4IsDHCPValid(NULL /* why is this here? */, pDhcpMsg, cbPv, &uMsgType))
+    {
+        m_uCurMsgType = uMsgType;
+        {
+            /* To avoid fight with event processing thread */
+            VBoxNetALock(this);
+            handleDhcpMsg(uMsgType, pDhcpMsg, cbPv);
+        }
+        m_uCurMsgType = UINT8_MAX;
+    }
+    else
+        debugPrint(1, true, "VBoxNetDHCP: Skipping invalid DHCP packet.\n"); /** @todo handle pure bootp clients too? */
+
+    m_pCurMsg = NULL;
+    m_cbCurMsg = 0;
+
+    return VINF_SUCCESS;
+}
+
+
+/**
+ * Handles a DHCP message.
+ *
+ * @returns true if handled, false if not.  (IGNORED BY CALLER)
+ * @param   uMsgType        The message type.
+ * @param   pDhcpMsg        The DHCP message.
+ * @param   cb              The size of the DHCP message.
+ */
+bool VBoxNetDhcp::handleDhcpMsg(uint8_t uMsgType, PCRTNETBOOTP pDhcpMsg, size_t cb)
+{
+    if (pDhcpMsg->bp_op == RTNETBOOTP_OP_REQUEST)
+    {
+        AssertPtrReturn(m_NetworkManager, false);
+
+        switch (uMsgType)
+        {
+            case RTNET_DHCP_MT_DISCOVER:
+                return m_NetworkManager->handleDhcpReqDiscover(pDhcpMsg, cb);
+
+            case RTNET_DHCP_MT_REQUEST:
+                return m_NetworkManager->handleDhcpReqRequest(pDhcpMsg, cb);
+
+            case RTNET_DHCP_MT_DECLINE:
+                return m_NetworkManager->handleDhcpReqDecline(pDhcpMsg, cb);
+
+            case RTNET_DHCP_MT_RELEASE:
+                return m_NetworkManager->handleDhcpReqRelease(pDhcpMsg, cb);
+
+            case RTNET_DHCP_MT_INFORM:
+                debugPrint(0, true, "Should we handle this?");
+                break;
+
+            default:
+                debugPrint(0, true, "Unexpected.");
+                break;
+        }
+    }
+    return false;
+}
+
+/**
+ * Print debug message depending on the m_cVerbosity level.
+ *
+ * @param   iMinLevel       The minimum m_cVerbosity level for this message.
+ * @param   fMsg            Whether to dump parts for the current DHCP message.
+ * @param   pszFmt          The message format string.
+ * @param   va              Optional arguments.
+ */
+void VBoxNetDhcp::debugPrintV(int iMinLevel, bool fMsg, const char *pszFmt, va_list va) const
+{
+    if (iMinLevel <= m_cVerbosity)
+    {
+        va_list vaCopy;                 /* This dude is *very* special, thus the copy. */
+        va_copy(vaCopy, va);
+        RTStrmPrintf(g_pStdErr, "VBoxNetDHCP: %s: %N\n", iMinLevel >= 2 ? "debug" : "info", pszFmt, &vaCopy);
+        va_end(vaCopy);
+
+        if (    fMsg
+            &&  m_cVerbosity >= 2
+            &&  m_pCurMsg)
+        {
+            /* XXX: export this to debugPrinfDhcpMsg or variant and other method export
+             *  to base class
+             */
+            const char *pszMsg = m_uCurMsgType != UINT8_MAX ? debugDhcpName(m_uCurMsgType) : "";
+            RTStrmPrintf(g_pStdErr, "VBoxNetDHCP: debug: %8s chaddr=%.6Rhxs ciaddr=%d.%d.%d.%d yiaddr=%d.%d.%d.%d siaddr=%d.%d.%d.%d xid=%#x\n",
+                         pszMsg,
+                         &m_pCurMsg->bp_chaddr,
+                         m_pCurMsg->bp_ciaddr.au8[0], m_pCurMsg->bp_ciaddr.au8[1], m_pCurMsg->bp_ciaddr.au8[2], m_pCurMsg->bp_ciaddr.au8[3],
+                         m_pCurMsg->bp_yiaddr.au8[0], m_pCurMsg->bp_yiaddr.au8[1], m_pCurMsg->bp_yiaddr.au8[2], m_pCurMsg->bp_yiaddr.au8[3],
+                         m_pCurMsg->bp_siaddr.au8[0], m_pCurMsg->bp_siaddr.au8[1], m_pCurMsg->bp_siaddr.au8[2], m_pCurMsg->bp_siaddr.au8[3],
+                         m_pCurMsg->bp_xid);
+        }
+    }
+}
+
+
+/**
+ * Gets the name of given DHCP message type.
+ *
+ * @returns Readonly name.
+ * @param   uMsgType        The message number.
+ */
+/* static */ const char *VBoxNetDhcp::debugDhcpName(uint8_t uMsgType)
+{
+    switch (uMsgType)
+    {
+        case 0:                         return "MT_00";
+        case RTNET_DHCP_MT_DISCOVER:    return "DISCOVER";
+        case RTNET_DHCP_MT_OFFER:       return "OFFER";
+        case RTNET_DHCP_MT_REQUEST:     return "REQUEST";
+        case RTNET_DHCP_MT_DECLINE:     return "DECLINE";
+        case RTNET_DHCP_MT_ACK:         return "ACK";
+        case RTNET_DHCP_MT_NAC:         return "NAC";
+        case RTNET_DHCP_MT_RELEASE:     return "RELEASE";
+        case RTNET_DHCP_MT_INFORM:      return "INFORM";
+        case 9:                         return "MT_09";
+        case 10:                        return "MT_0a";
+        case 11:                        return "MT_0b";
+        case 12:                        return "MT_0c";
+        case 13:                        return "MT_0d";
+        case 14:                        return "MT_0e";
+        case 15:                        return "MT_0f";
+        case 16:                        return "MT_10";
+        case 17:                        return "MT_11";
+        case 18:                        return "MT_12";
+        case 19:                        return "MT_13";
+        case UINT8_MAX:                 return "MT_ff";
+        default:                        return "UNKNOWN";
+    }
+}
+
+
+int VBoxNetDhcp::initNoMain()
+{
+    CmdParameterIterator it;
+
+    RTNETADDRIPV4 address = getIpv4Address();
+    RTNETADDRIPV4 netmask = getIpv4Netmask();
+    RTNETADDRIPV4 networkId;
+    networkId.u = address.u & netmask.u;
+
+    RTNETADDRIPV4 UpperAddress;
+    RTNETADDRIPV4 LowerAddress = networkId;
+    UpperAddress.u = RT_H2N_U32(RT_N2H_U32(LowerAddress.u) | RT_N2H_U32(netmask.u));
+
+    for (it = CmdParameterll.begin(); it != CmdParameterll.end(); ++it)
+    {
+        switch(it->Key)
+        {
+            case 'l':
+                RTNetStrToIPv4Addr(it->strValue.c_str(), &LowerAddress);
+                break;
+
+            case 'u':
+                RTNetStrToIPv4Addr(it->strValue.c_str(), &UpperAddress);
+                break;
+            case 'b':
+                break;
+
+        }
+    }
+
+    ConfigurationManager *confManager = ConfigurationManager::getConfigurationManager();
+    AssertPtrReturn(confManager, VERR_INTERNAL_ERROR);
+    confManager->addNetwork(unconst(g_RootConfig),
+                            networkId,
+                            netmask,
+                            LowerAddress,
+                            UpperAddress);
+
+    return VINF_SUCCESS;
+}
+
+
+int VBoxNetDhcp::initWithMain()
+{
+    /* ok, here we should initiate instance of dhcp server
+     * and listener for Dhcp configuration events
+     */
+    AssertRCReturn(virtualbox.isNull(), VERR_INTERNAL_ERROR);
+    std::string networkName = getNetworkName();
+
+    int rc = findDhcpServer(virtualbox, networkName, m_DhcpServer);
+    AssertRCReturn(rc, rc);
+
+    rc = findNatNetwork(virtualbox, networkName, m_NATNetwork);
+    AssertRCReturn(rc, rc);
+
+    BOOL fNeedDhcpServer = isDhcpRequired(m_NATNetwork);
+    if (!fNeedDhcpServer)
+        return VERR_CANCELLED;
+
+    RTNETADDRIPV4 gateway;
+    com::Bstr strGateway;
+    HRESULT hrc = m_NATNetwork->COMGETTER(Gateway)(strGateway.asOutParam());
+    AssertComRCReturn(hrc, VERR_INTERNAL_ERROR);
+    RTNetStrToIPv4Addr(com::Utf8Str(strGateway).c_str(), &gateway);
+
+    ConfigurationManager *confManager = ConfigurationManager::getConfigurationManager();
+    AssertPtrReturn(confManager, VERR_INTERNAL_ERROR);
+    confManager->addToAddressList(RTNET_DHCP_OPT_ROUTERS, gateway);
+
+    rc = fetchAndUpdateDnsInfo();
+    AssertMsgRCReturn(rc, ("Wasn't able to fetch Dns info"), rc);
+
+    {
+        ComEventTypeArray eventTypes;
+        eventTypes.push_back(VBoxEventType_OnHostNameResolutionConfigurationChange);
+        eventTypes.push_back(VBoxEventType_OnNATNetworkStartStop);
+        rc = createNatListener(m_VBoxListener, virtualbox, this, eventTypes);
+        AssertRCReturn(rc, rc);
+    }
+
+    {
+        ComEventTypeArray eventTypes;
+        eventTypes.push_back(VBoxEventType_OnVBoxSVCAvailabilityChanged);
+        rc = createClientListener(m_VBoxClientListener, virtualboxClient, this, eventTypes);
+        AssertRCReturn(rc, rc);
+    }
+
+    RTNETADDRIPV4 LowerAddress;
+    rc = configGetBoundryAddress(m_DhcpServer, false, LowerAddress);
+    AssertMsgRCReturn(rc, ("can't get lower boundrary adderss'"),rc);
+
+    RTNETADDRIPV4 UpperAddress;
+    rc = configGetBoundryAddress(m_DhcpServer, true, UpperAddress);
+    AssertMsgRCReturn(rc, ("can't get upper boundrary adderss'"),rc);
+
+    RTNETADDRIPV4 address = getIpv4Address();
+    RTNETADDRIPV4 netmask = getIpv4Netmask();
+    RTNETADDRIPV4 networkId = networkid(address, netmask);
+    std::string name = std::string("default");
+
+    confManager->addNetwork(unconst(g_RootConfig),
+                            networkId,
+                            netmask,
+                            LowerAddress,
+                            UpperAddress);
+
+    com::Bstr bstr;
+    hrc = virtualbox->COMGETTER(HomeFolder)(bstr.asOutParam());
+    com::Utf8StrFmt strXmlLeaseFile("%ls%c%s.leases",
+                                    bstr.raw(), RTPATH_DELIMITER, networkName.c_str());
+    confManager->loadFromFile(strXmlLeaseFile);
+
+    return VINF_SUCCESS;
+}
+
+
+int VBoxNetDhcp::fetchAndUpdateDnsInfo()
+{
+    ComHostPtr host;
+    if (SUCCEEDED(virtualbox->COMGETTER(Host)(host.asOutParam())))
+    {
+        AddressToOffsetMapping mapIp4Addr2Off;
+        int rc = localMappings(m_NATNetwork, mapIp4Addr2Off);
+        /* XXX: here could be several cases: 1. COM error, 2. not found (empty) 3. ? */
+        AssertMsgRCReturn(rc, ("Can't fetch local mappings"), rc);
+
+        RTNETADDRIPV4 address = getIpv4Address();
+        RTNETADDRIPV4 netmask = getIpv4Netmask();
+
+        AddressList nameservers;
+        rc = hostDnsServers(host, networkid(address, netmask), mapIp4Addr2Off, nameservers);
+        AssertMsgRCReturn(rc, ("Debug me!!!"), rc);
+        /* XXX: Search strings */
+
+        std::string domain;
+        rc = hostDnsDomain(host, domain);
+        AssertMsgRCReturn(rc, ("Debug me!!"), rc);
+
+        {
+            VBoxNetALock(this);
+            ConfigurationManager *confManager = ConfigurationManager::getConfigurationManager();
+            confManager->flushAddressList(RTNET_DHCP_OPT_DNS);
+
+            for (AddressList::iterator it = nameservers.begin(); it != nameservers.end(); ++it)
+                confManager->addToAddressList(RTNET_DHCP_OPT_DNS, *it);
+
+            confManager->setString(RTNET_DHCP_OPT_DOMAIN_NAME, domain);
+        }
+    }
+
+    return VINF_SUCCESS;
+}
+
+
+int VBoxNetDhcp::hostDnsServers(const ComHostPtr& host,
+                                const RTNETADDRIPV4& networkid,
+                                const AddressToOffsetMapping& mapping,
+                                AddressList& servers)
+{
+    ComBstrArray strs;
+
+    HRESULT hrc = host->COMGETTER(NameServers)(ComSafeArrayAsOutParam(strs));
+    if (FAILED(hrc))
+        return VERR_NOT_FOUND;
+
+    /*
+     * Recent fashion is to run dnsmasq on 127.0.1.1 which we
+     * currently can't map.  If that's the only nameserver we've got,
+     * we need to use DNS proxy for VMs to reach it.
+     */
+    bool fUnmappedLoopback = false;
+
+    for (size_t i = 0; i < strs.size(); ++i)
+    {
+        RTNETADDRIPV4 addr;
+        int rc;
+
+        rc = RTNetStrToIPv4Addr(com::Utf8Str(strs[i]).c_str(), &addr);
+        if (RT_FAILURE(rc))
+            continue;
+
+        if (addr.u == INADDR_ANY)
+        {
+            /*
+             * This doesn't seem to be very well documented except for
+             * RTFS of res_init.c, but INADDR_ANY is a valid value for
+             * for "nameserver".
+             */
+            addr.u = RT_H2N_U32_C(INADDR_LOOPBACK);
+        }
+
+        if (addr.au8[0] == 127)
+        {
+            AddressToOffsetMapping::const_iterator remap(mapping.find(addr));
+
+            if (remap != mapping.end())
+            {
+                int offset = remap->second;
+                addr.u = RT_H2N_U32(RT_N2H_U32(networkid.u) + offset);
+            }
+            else
+            {
+                fUnmappedLoopback = true;
+                continue;
+            }
+        }
+
+        servers.push_back(addr);
+    }
+
+    if (servers.empty() && fUnmappedLoopback)
+    {
+        RTNETADDRIPV4 proxy;
+
+        proxy.u = networkid.u | RT_H2N_U32_C(1U);
+        servers.push_back(proxy);
+    }
+
+    return VINF_SUCCESS;
+}
+
+
+HRESULT VBoxNetDhcp::HandleEvent(VBoxEventType_T aEventType, IEvent *pEvent)
+{
+    switch (aEventType)
+    {
+        case VBoxEventType_OnHostNameResolutionConfigurationChange:
+            fetchAndUpdateDnsInfo();
+            break;
+
+        case VBoxEventType_OnNATNetworkStartStop:
+        {
+            ComPtr <INATNetworkStartStopEvent> pStartStopEvent = pEvent;
+
+            com::Bstr networkName;
+            HRESULT hrc = pStartStopEvent->COMGETTER(NetworkName)(networkName.asOutParam());
+            AssertComRCReturn(hrc, hrc);
+            if (networkName.compare(getNetworkName().c_str()))
+                break; /* change not for our network */
+
+            BOOL fStart = TRUE;
+            hrc = pStartStopEvent->COMGETTER(StartEvent)(&fStart);
+            AssertComRCReturn(hrc, hrc);
+            if (!fStart)
+                shutdown();
+            break;
+        }
+
+        case VBoxEventType_OnVBoxSVCAvailabilityChanged:
+        {
+            shutdown();
+            break;
+        }
+
+        default: break; /* Shut up MSC. */
+    }
+
+    return S_OK;
+}
+
+#ifdef RT_OS_WINDOWS
+
+/** The class name for the DIFx-killable window.    */
+static WCHAR g_wszWndClassName[] = L"VBoxNetDHCPClass";
+/** Whether to exit the process on quit.   */
+static bool g_fExitProcessOnQuit = true;
+
+/**
+ * Window procedure for making us DIFx-killable.
+ */
+static LRESULT CALLBACK DIFxKillableWindowProc(HWND hwnd, UINT uMsg, WPARAM wParam, LPARAM lParam)
+{
+    if (uMsg == WM_DESTROY)
+    {
+        PostQuitMessage(0);
+        return 0;
+    }
+    return DefWindowProc(hwnd, uMsg, wParam, lParam);
+}
+
+/** @callback_method_impl{FNRTTHREAD,
+ *      Thread that creates service a window the DIFx can destroy, thereby
+ *      triggering process termination. }
+ */
+static DECLCALLBACK(int) DIFxKillableProcessThreadProc(RTTHREAD hThreadSelf, void *pvUser)
+{
+    RT_NOREF(hThreadSelf, pvUser);
+    HINSTANCE hInstance = (HINSTANCE)GetModuleHandle(NULL);
+
+    /* Register the Window Class. */
+    WNDCLASSW WndCls;
+    WndCls.style         = 0;
+    WndCls.lpfnWndProc   = DIFxKillableWindowProc;
+    WndCls.cbClsExtra    = 0;
+    WndCls.cbWndExtra    = sizeof(void *);
+    WndCls.hInstance     = hInstance;
+    WndCls.hIcon         = NULL;
+    WndCls.hCursor       = NULL;
+    WndCls.hbrBackground = (HBRUSH)(COLOR_BACKGROUND + 1);
+    WndCls.lpszMenuName  = NULL;
+    WndCls.lpszClassName = g_wszWndClassName;
+
+    ATOM atomWindowClass = RegisterClassW(&WndCls);
+    if (atomWindowClass != 0)
+    {
+        /* Create the window. */
+        HWND hwnd = CreateWindowExW(WS_EX_TOOLWINDOW | WS_EX_TRANSPARENT | WS_EX_TOPMOST,
+                                    g_wszWndClassName, g_wszWndClassName,
+                                    WS_POPUPWINDOW,
+                                    -200, -200, 100, 100, NULL, NULL, hInstance, NULL);
+        if (hwnd)
+        {
+            SetWindowPos(hwnd, HWND_TOPMOST, -200, -200, 0, 0,
+                         SWP_NOACTIVATE | SWP_HIDEWINDOW | SWP_NOCOPYBITS | SWP_NOREDRAW | SWP_NOSIZE);
+
+            MSG msg;
+            while (GetMessage(&msg, NULL, 0, 0))
+            {
+                TranslateMessage(&msg);
+                DispatchMessage(&msg);
+            }
+
+            DestroyWindow(hwnd);
+        }
+
+        UnregisterClassW(g_wszWndClassName, hInstance);
+
+        if (hwnd && g_fExitProcessOnQuit)
+            exit(0);
+    }
+    return 0;
+}
+
+#endif /* RT_OS_WINDOWS */
+
+/**
+ *  Entry point.
+ */
+extern "C" DECLEXPORT(int) TrustedMain(int argc, char **argv)
+{
+    /*
+     * Instantiate the DHCP server and hand it the options.
+     */
+    VBoxNetDhcp *pDhcp = new VBoxNetDhcp();
+    if (!pDhcp)
+    {
+        RTStrmPrintf(g_pStdErr, "VBoxNetDHCP: new VBoxNetDhcp failed!\n");
+        return 1;
+    }
+
+    RTEXITCODE rcExit = (RTEXITCODE)pDhcp->parseArgs(argc - 1, argv + 1);
+    if (rcExit != RTEXITCODE_SUCCESS)
+        return rcExit;
+
+#ifdef RT_OS_WINDOWS
+    /* DIFx hack. */
+    RTTHREAD hMakeUseKillableThread = NIL_RTTHREAD;
+    int rc2 = RTThreadCreate(&hMakeUseKillableThread, DIFxKillableProcessThreadProc, NULL, 0,
+                             RTTHREADTYPE_DEFAULT, RTTHREADFLAGS_WAITABLE, "DIFxKill");
+    if (RT_FAILURE(rc2))
+        hMakeUseKillableThread = NIL_RTTHREAD;
+#endif
+
+    pDhcp->init();
+
+    /*
+     * Try connect the server to the network.
+     */
+    int rc = pDhcp->tryGoOnline();
+    if (RT_SUCCESS(rc))
+    {
+        /*
+         * Process requests.
+         */
+        g_pDhcp = pDhcp;
+        rc = pDhcp->run();
+        pDhcp->done();
+
+        g_pDhcp = NULL;
+    }
+    delete pDhcp;
+
+#ifdef RT_OS_WINDOWS
+    /* Kill DIFx hack. */
+    if (hMakeUseKillableThread != NIL_RTTHREAD)
+    {
+        g_fExitProcessOnQuit = false;
+        PostThreadMessage((DWORD)RTThreadGetNative(hMakeUseKillableThread), WM_QUIT, 0, 0);
+        RTThreadWait(hMakeUseKillableThread, RT_MS_1SEC * 5U, NULL);
+    }
+#endif
+
+    return RT_SUCCESS(rc) ? RTEXITCODE_SUCCESS : RTEXITCODE_FAILURE;
+}
+
+
+#ifndef VBOX_WITH_HARDENING
+
+int main(int argc, char **argv)
+{
+    int rc = RTR3InitExe(argc, &argv, RTR3INIT_FLAGS_SUPLIB);
+    if (RT_FAILURE(rc))
+        return RTMsgInitFailure(rc);
+
+    return TrustedMain(argc, argv);
+}
+
+# ifdef RT_OS_WINDOWS
+
+
+
+/** (We don't want a console usually.) */
+int WINAPI WinMain(HINSTANCE hInstance, HINSTANCE hPrevInstance, LPSTR lpCmdLine, int nCmdShow)
+{
+    NOREF(hInstance); NOREF(hPrevInstance); NOREF(lpCmdLine); NOREF(nCmdShow);
+    return main(__argc, __argv);
+}
+# endif /* RT_OS_WINDOWS */
+
+#endif /* !VBOX_WITH_HARDENING */
+
diff --git a/src/VBox/NetworkServices/DHCP/VBoxNetDHCP.rc b/src/VBox/NetworkServices/DHCP/VBoxNetDHCP.rc
new file mode 100644
index 00000000..5a8b64aa
--- /dev/null
+++ b/src/VBox/NetworkServices/DHCP/VBoxNetDHCP.rc
@@ -0,0 +1,55 @@
+/* $Id: VBoxNetDHCP.rc $ */
+/** @file
+ * VBoxNetDHCP - Resource file containing version info.
+ */
+
+/*
+ * Copyright (C) 2015-2019 Oracle Corporation
+ *
+ * This file is part of VirtualBox Open Source Edition (OSE), as
+ * available from http://www.virtualbox.org. This file is free software;
+ * you can redistribute it and/or modify it under the terms of the GNU
+ * General Public License (GPL) as published by the Free Software
+ * Foundation, in version 2 as it comes in the "COPYING" file of the
+ * VirtualBox OSE distribution. VirtualBox OSE is distributed in the
+ * hope that it will be useful, but WITHOUT ANY WARRANTY of any kind.
+ */
+
+#include <windows.h>
+#include <VBox/version.h>
+
+LANGUAGE LANG_ENGLISH, SUBLANG_ENGLISH_US
+
+VS_VERSION_INFO VERSIONINFO
+  FILEVERSION      VBOX_RC_FILE_VERSION
+  PRODUCTVERSION   VBOX_RC_FILE_VERSION
+  FILEFLAGSMASK    VS_FFI_FILEFLAGSMASK
+  FILEFLAGS        VBOX_RC_FILE_FLAGS
+  FILEOS           VBOX_RC_FILE_OS
+  FILETYPE         VBOX_RC_TYPE_DLL
+  FILESUBTYPE      VFT2_UNKNOWN
+BEGIN
+  BLOCK "StringFileInfo"
+  BEGIN
+    BLOCK "040904b0" // Lang=US English, CharSet=Unicode
+    BEGIN
+      VALUE "CompanyName",      VBOX_RC_COMPANY_NAME
+      VALUE "FileDescription",  "VirtualBox DHCP Server\0"
+      VALUE "FileVersion",      VBOX_RC_FILE_VERSION_STR
+      VALUE "InternalName",     "VBoxNetDHCP\0"
+      VALUE "LegalCopyright",   VBOX_RC_LEGAL_COPYRIGHT
+      VALUE "OriginalFilename", "VBoxNetDHCP.dll\0"
+      VALUE "ProductName",      VBOX_RC_PRODUCT_NAME_STR
+      VALUE "ProductVersion",   VBOX_RC_PRODUCT_VERSION_STR
+      VBOX_RC_MORE_STRINGS
+    END
+  END
+  BLOCK "VarFileInfo"
+  BEGIN
+    VALUE "Translation", 0x409, 1200
+  END
+END
+
+/* Creates the application icon. */
+#include "VBoxNetDHCP-icon.rc"
+
diff --git a/src/VBox/NetworkServices/DHCP/VBoxNetDHCPHardened.cpp b/src/VBox/NetworkServices/DHCP/VBoxNetDHCPHardened.cpp
new file mode 100644
index 00000000..8ed60a98
--- /dev/null
+++ b/src/VBox/NetworkServices/DHCP/VBoxNetDHCPHardened.cpp
@@ -0,0 +1,25 @@
+/* $Id: VBoxNetDHCPHardened.cpp $ */
+/** @file
+ * VBoxNetDHCP - Hardened main().
+ */
+
+/*
+ * Copyright (C) 2009-2019 Oracle Corporation
+ *
+ * This file is part of VirtualBox Open Source Edition (OSE), as
+ * available from http://www.virtualbox.org. This file is free software;
+ * you can redistribute it and/or modify it under the terms of the GNU
+ * General Public License (GPL) as published by the Free Software
+ * Foundation, in version 2 as it comes in the "COPYING" file of the
+ * VirtualBox OSE distribution. VirtualBox OSE is distributed in the
+ * hope that it will be useful, but WITHOUT ANY WARRANTY of any kind.
+ */
+
+#include <VBox/sup.h>
+
+
+int main(int argc, char **argv, char **envp)
+{
+    return SUPR3HardenedMain("VBoxNetDHCP", 0 /* fFlags */, argc, argv, envp);
+}
+