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202 | /* -*- 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/packages/XPackageEncryption.hpp>
#include <oox/ole/olestorage.hxx>
#include <oox/helper/binaryinputstream.hxx>
#include <filter/msfilter/mscodec.hxx>
#include <com/sun/star/task/PasswordRequestMode.hpp>
#include <comphelper/docpasswordrequest.hxx>
#include <comphelper/stillreadwriteinteraction.hxx>
#include <com/sun/star/task/InteractionHandler.hpp>
#include <com/sun/star/task/PasswordContainer.hpp>
#include <com/sun/star/task/XInteractionHandler.hpp>
#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())
{
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; 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; 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
aDataSpaceStream.readUnicodeArray(aReferenceComponentNameLength / 2);
aDataSpaceStream.skip((4 - (aReferenceComponentNameLength & 3)) & 3); // Skip padding
}
sal_uInt32 aDataSpaceNameLength = aDataSpaceStream.readuInt32();
sDataSpaceName = aDataSpaceStream.readUnicodeArray(aDataSpaceNameLength / 2);
aDataSpaceStream.skip((4 - (aDataSpaceNameLength & 3)) & 3); // Skip padding
}
}
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)<--- If condition 'bResult' is true, the function will return/exit
return mxPackageEncryption->checkDataIntegrity();
return bResult;<--- Returning identical expression 'bResult'
}
} // namespace oox::crypto
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