Adding upstream version 4:7.4.7.upstream/4%7.4.7upstream

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

1 files changed, 223 insertions, 0 deletions

diff --git a/oox/source/crypto/DocumentDecryption.cxx b/oox/source/crypto/DocumentDecryption.cxx
new file mode 100644
index 000000000..cae8a1331
--- /dev/null
+++ b/oox/source/crypto/DocumentDecryption.cxx
@@ -0,0 +1,223 @@
+/* -*- Mode: C++; tab-width: 4; indent-tabs-mode: nil; c-basic-offset: 4 -*- */
+/*
+ * This file is part of the LibreOffice project.
+ *
+ * This Source Code Form is subject to the terms of the Mozilla Public
+ * License, v. 2.0. If a copy of the MPL was not distributed with this
+ * file, You can obtain one at http://mozilla.org/MPL/2.0/.
+ *
+ */
+
+#include <oox/crypto/DocumentDecryption.hxx>
+
+#include <comphelper/sequenceashashmap.hxx>
+
+#include <com/sun/star/beans/NamedValue.hpp>
+#include <com/sun/star/io/XSeekable.hpp>
+#include <com/sun/star/io/XStream.hpp>
+#include <com/sun/star/io/IOException.hpp>
+#include <com/sun/star/uno/XComponentContext.hpp>
+#include <com/sun/star/packages/XPackageEncryption.hpp>
+#include <oox/ole/olestorage.hxx>
+#include <oox/helper/binaryinputstream.hxx>
+
+#include <sal/log.hxx>
+
+namespace
+{
+void lcl_getListOfStreams(oox::StorageBase* pStorage, std::vector<OUString>& rElementNames)
+{
+    std::vector<OUString> oElementNames;
+    pStorage->getElementNames(oElementNames);
+    for (const auto& sName : oElementNames)
+    {
+        oox::StorageRef rSubStorage = pStorage->openSubStorage(sName, false);
+        if (rSubStorage && rSubStorage->isStorage())
+        {
+            lcl_getListOfStreams(rSubStorage.get(), rElementNames);
+        }
+        else
+        {
+            if (pStorage->isRootStorage())
+                rElementNames.push_back(sName);
+            else
+                rElementNames.push_back(pStorage->getPath() + "/" + sName);
+        }
+    }
+}
+}
+
+namespace oox::crypto
+{
+using namespace css;
+
+DocumentDecryption::DocumentDecryption(
+    const css::uno::Reference<css::uno::XComponentContext>& rxContext,
+    oox::ole::OleStorage& rOleStorage)
+    : mxContext(rxContext)
+    , mrOleStorage(rOleStorage)
+{
+    // Get OLE streams into sequences for later use in CryptoEngine
+    std::vector<OUString> aStreamNames;
+    lcl_getListOfStreams(&mrOleStorage, aStreamNames);
+
+    comphelper::SequenceAsHashMap aStreamsData;
+    for (const auto& sStreamName : aStreamNames)
+    {
+        uno::Reference<io::XInputStream> xStream = mrOleStorage.openInputStream(sStreamName);
+        if (!xStream.is())
+            throw io::IOException("Cannot open OLE input stream for " + sStreamName + "!");
+
+        BinaryXInputStream aBinaryInputStream(xStream, true);
+
+        css::uno::Sequence<sal_Int8> oData;
+        sal_Int32 nStreamSize = aBinaryInputStream.size();
+        sal_Int32 nReadBytes = aBinaryInputStream.readData(oData, nStreamSize);
+
+        if (nStreamSize != nReadBytes)
+        {
+            SAL_WARN("oox", "OLE stream invalid content");
+            throw io::IOException("OLE stream invalid content for " + sStreamName + "!");
+        }
+
+        aStreamsData[sStreamName] <<= oData;
+    }
+    maStreamsSequence = aStreamsData.getAsConstNamedValueList();
+}
+
+bool DocumentDecryption::generateEncryptionKey(const OUString& rPassword)
+{
+    if (mxPackageEncryption.is())
+        return mxPackageEncryption->generateEncryptionKey(rPassword);
+    return false;
+}
+
+bool DocumentDecryption::readEncryptionInfo()
+{
+    if (!mrOleStorage.isStorage())
+        return false;
+
+    // Read 0x6DataSpaces/DataSpaceMap
+    uno::Reference<io::XInputStream> xDataSpaceMap
+        = mrOleStorage.openInputStream("\006DataSpaces/DataSpaceMap");
+    OUString sDataSpaceName;
+
+    if (xDataSpaceMap.is())
+    {
+        bool bBroken = false;
+
+        BinaryXInputStream aDataSpaceStream(xDataSpaceMap, true);
+        sal_uInt32 aHeaderLength = aDataSpaceStream.readuInt32();
+        SAL_WARN_IF(aHeaderLength != 8, "oox",
+                    "DataSpaceMap length != 8 is not supported. Some content may be skipped");
+        sal_uInt32 aEntryCount = aDataSpaceStream.readuInt32();
+        SAL_WARN_IF(aEntryCount != 1, "oox",
+                    "DataSpaceMap contains more than one entry. Some content may be skipped");
+
+        // Read each DataSpaceMapEntry (MS-OFFCRYPTO 2.1.6.1)
+        for (sal_uInt32 i = 0; i < aEntryCount && !bBroken; i++)
+        {
+            // entryLen unused for the moment
+            aDataSpaceStream.skip(sizeof(sal_uInt32));
+
+            // Read each DataSpaceReferenceComponent (MS-OFFCRYPTO 2.1.6.2)
+            sal_uInt32 aReferenceComponentCount = aDataSpaceStream.readuInt32();
+            for (sal_uInt32 j = 0; j < aReferenceComponentCount && !bBroken; j++)
+            {
+                // Read next reference component
+                // refComponentType unused for the moment
+                aDataSpaceStream.skip(sizeof(sal_uInt32));
+                sal_uInt32 aReferenceComponentNameLength = aDataSpaceStream.readuInt32();
+                // sReferenceComponentName unused for the moment
+                if (aDataSpaceStream.getRemaining() < aReferenceComponentNameLength)
+                {
+                    bBroken = true;
+                    break;
+                }
+                aDataSpaceStream.readUnicodeArray(aReferenceComponentNameLength / 2);
+                aDataSpaceStream.skip((4 - (aReferenceComponentNameLength & 3))
+                                      & 3); // Skip padding
+
+                bBroken |= aDataSpaceStream.isEof();
+            }
+
+            sal_uInt32 aDataSpaceNameLength = aDataSpaceStream.readuInt32();
+            if (aDataSpaceStream.getRemaining() < aDataSpaceNameLength)
+            {
+                bBroken = true;
+                break;
+            }
+            sDataSpaceName = aDataSpaceStream.readUnicodeArray(aDataSpaceNameLength / 2);
+            aDataSpaceStream.skip((4 - (aDataSpaceNameLength & 3)) & 3); // Skip padding
+
+            bBroken |= aDataSpaceStream.isEof();
+        }
+
+        if (bBroken)
+        {
+            SAL_WARN("oox", "EOF on parsing DataSpaceMapEntry table");
+            return false;
+        }
+    }
+    else
+    {
+        // Fallback for documents generated by LO: they sometimes do not have all
+        // required by MS-OFFCRYPTO specification streams (0x6DataSpaces/DataSpaceMap and others)
+        SAL_WARN("oox", "Encrypted package does not contain DataSpaceMap");
+        sDataSpaceName = "StrongEncryptionDataSpace";
+    }
+
+    uno::Sequence<uno::Any> aArguments;
+    mxPackageEncryption.set(
+        mxContext->getServiceManager()->createInstanceWithArgumentsAndContext(
+            "com.sun.star.comp.oox.crypto." + sDataSpaceName, aArguments, mxContext),
+        css::uno::UNO_QUERY);
+
+    if (!mxPackageEncryption.is())
+    {
+        // we do not know how to decrypt this document
+        return false;
+    }
+
+    return mxPackageEncryption->readEncryptionInfo(maStreamsSequence);
+}
+
+uno::Sequence<beans::NamedValue> DocumentDecryption::createEncryptionData(const OUString& rPassword)
+{
+    if (!mxPackageEncryption.is())
+        return uno::Sequence<beans::NamedValue>();
+
+    return mxPackageEncryption->createEncryptionData(rPassword);
+}
+
+bool DocumentDecryption::decrypt(const uno::Reference<io::XStream>& xDocumentStream)
+{
+    bool bResult = false;
+
+    if (!mrOleStorage.isStorage())
+        return false;
+
+    if (!mxPackageEncryption.is())
+        return false;
+
+    // open the required input streams in the encrypted package
+    uno::Reference<io::XInputStream> xEncryptedPackage
+        = mrOleStorage.openInputStream("EncryptedPackage");
+
+    // create temporary file for unencrypted package
+    uno::Reference<io::XOutputStream> xDecryptedPackage = xDocumentStream->getOutputStream();
+
+    bResult = mxPackageEncryption->decrypt(xEncryptedPackage, xDecryptedPackage);
+
+    css::uno::Reference<io::XSeekable> xSeekable(xDecryptedPackage, css::uno::UNO_QUERY);
+    xSeekable->seek(0);
+
+    if (bResult)
+        return mxPackageEncryption->checkDataIntegrity();
+
+    return bResult;
+}
+
+} // namespace oox::crypto
+
+/* vim:set shiftwidth=4 softtabstop=4 expandtab: */