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, 1263 insertions, 0 deletions

diff --git a/package/source/zipapi/ZipFile.cxx b/package/source/zipapi/ZipFile.cxx
new file mode 100644
index 000000000..79dc5bb68
--- /dev/null
+++ b/package/source/zipapi/ZipFile.cxx
@@ -0,0 +1,1263 @@
+/* -*- 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/.
+ *
+ * This file incorporates work covered by the following license notice:
+ *
+ *   Licensed to the Apache Software Foundation (ASF) under one or more
+ *   contributor license agreements. See the NOTICE file distributed
+ *   with this work for additional information regarding copyright
+ *   ownership. The ASF licenses this file to you under the Apache
+ *   License, Version 2.0 (the "License"); you may not use this file
+ *   except in compliance with the License. You may obtain a copy of
+ *   the License at http://www.apache.org/licenses/LICENSE-2.0 .
+ */
+
+#include <com/sun/star/io/BufferSizeExceededException.hpp>
+#include <com/sun/star/io/NotConnectedException.hpp>
+#include <com/sun/star/lang/IllegalArgumentException.hpp>
+#include <com/sun/star/lang/XUnoTunnel.hpp>
+#include <com/sun/star/packages/NoEncryptionException.hpp>
+#include <com/sun/star/packages/WrongPasswordException.hpp>
+#include <com/sun/star/packages/zip/ZipConstants.hpp>
+#include <com/sun/star/packages/zip/ZipException.hpp>
+#include <com/sun/star/packages/zip/ZipIOException.hpp>
+#include <com/sun/star/xml/crypto/XCipherContext.hpp>
+#include <com/sun/star/xml/crypto/XDigestContext.hpp>
+#include <com/sun/star/xml/crypto/CipherID.hpp>
+#include <com/sun/star/xml/crypto/DigestID.hpp>
+#include <com/sun/star/xml/crypto/NSSInitializer.hpp>
+
+#include <comphelper/bytereader.hxx>
+#include <comphelper/storagehelper.hxx>
+#include <comphelper/processfactory.hxx>
+#include <rtl/digest.h>
+#include <sal/log.hxx>
+#include <o3tl/safeint.hxx>
+#include <osl/diagnose.h>
+
+#include <algorithm>
+#include <iterator>
+#include <vector>
+
+#include "blowfishcontext.hxx"
+#include "sha1context.hxx"
+#include <ZipFile.hxx>
+#include <ZipEnumeration.hxx>
+#include "XUnbufferedStream.hxx"
+#include "XBufferedThreadedStream.hxx"
+#include <PackageConstants.hxx>
+#include <EncryptedDataHeader.hxx>
+#include <EncryptionData.hxx>
+#include "MemoryByteGrabber.hxx"
+
+#include <CRC32.hxx>
+
+using namespace com::sun::star;
+using namespace com::sun::star::io;
+using namespace com::sun::star::uno;
+using namespace com::sun::star::lang;
+using namespace com::sun::star::packages;
+using namespace com::sun::star::packages::zip;
+using namespace com::sun::star::packages::zip::ZipConstants;
+
+using ZipUtils::Inflater;
+
+#if OSL_DEBUG_LEVEL > 0
+#define THROW_WHERE SAL_WHERE
+#else
+#define THROW_WHERE ""
+#endif
+
+/** This class is used to read entries from a zip file
+ */
+ZipFile::ZipFile( const rtl::Reference<comphelper::RefCountedMutex>& aMutexHolder,
+                  uno::Reference < XInputStream > const &xInput,
+                  const uno::Reference < XComponentContext > & rxContext,
+                  bool bInitialise )
+: m_aMutexHolder( aMutexHolder )
+, aGrabber( xInput )
+, aInflater( true )
+, xStream(xInput)
+, m_xContext ( rxContext )
+, bRecoveryMode( false )
+{
+    if (bInitialise && readCEN() == -1 )
+    {
+        aEntries.clear();
+        throw ZipException( "stream data looks to be broken" );
+    }
+}
+
+ZipFile::ZipFile( const rtl::Reference< comphelper::RefCountedMutex >& aMutexHolder,
+                  uno::Reference < XInputStream > const &xInput,
+                  const uno::Reference < XComponentContext > & rxContext,
+                  bool bInitialise, bool bForceRecovery)
+: m_aMutexHolder( aMutexHolder )
+, aGrabber( xInput )
+, aInflater( true )
+, xStream(xInput)
+, m_xContext ( rxContext )
+, bRecoveryMode( bForceRecovery )
+{
+    if (bInitialise)
+    {
+        if ( bForceRecovery )
+        {
+            recover();
+        }
+        else if ( readCEN() == -1 )
+        {
+            aEntries.clear();
+            throw ZipException("stream data looks to be broken" );
+        }
+    }
+}
+
+ZipFile::~ZipFile()
+{
+    aEntries.clear();
+}
+
+void ZipFile::setInputStream ( const uno::Reference < XInputStream >& xNewStream )
+{
+    ::osl::MutexGuard aGuard( m_aMutexHolder->GetMutex() );
+
+    xStream = xNewStream;
+    aGrabber.setInputStream ( xStream );
+}
+
+uno::Reference< xml::crypto::XDigestContext > ZipFile::StaticGetDigestContextForChecksum( const uno::Reference< uno::XComponentContext >& xArgContext, const ::rtl::Reference< EncryptionData >& xEncryptionData )
+{
+    uno::Reference< xml::crypto::XDigestContext > xDigestContext;
+    if ( xEncryptionData->m_nCheckAlg == xml::crypto::DigestID::SHA256_1K )
+    {
+        uno::Reference< uno::XComponentContext > xContext = xArgContext;
+        if ( !xContext.is() )
+            xContext = comphelper::getProcessComponentContext();
+
+        uno::Reference< xml::crypto::XNSSInitializer > xDigestContextSupplier = xml::crypto::NSSInitializer::create( xContext );
+
+        xDigestContext.set( xDigestContextSupplier->getDigestContext( xEncryptionData->m_nCheckAlg, uno::Sequence< beans::NamedValue >() ), uno::UNO_SET_THROW );
+    }
+    else if ( xEncryptionData->m_nCheckAlg == xml::crypto::DigestID::SHA1_1K )
+    {
+        if (xEncryptionData->m_bTryWrongSHA1)
+        {
+            xDigestContext.set(StarOfficeSHA1DigestContext::Create(), uno::UNO_SET_THROW);
+        }
+        else
+        {
+            xDigestContext.set(CorrectSHA1DigestContext::Create(), uno::UNO_SET_THROW);
+        }
+    }
+
+    return xDigestContext;
+}
+
+uno::Reference< xml::crypto::XCipherContext > ZipFile::StaticGetCipher( const uno::Reference< uno::XComponentContext >& xArgContext, const ::rtl::Reference< EncryptionData >& xEncryptionData, bool bEncrypt )
+{
+    uno::Reference< xml::crypto::XCipherContext > xResult;
+
+    if (xEncryptionData->m_nDerivedKeySize < 0)
+    {
+        throw ZipIOException("Invalid derived key length!" );
+    }
+
+    uno::Sequence< sal_Int8 > aDerivedKey( xEncryptionData->m_nDerivedKeySize );
+    if ( !xEncryptionData->m_nIterationCount &&
+         xEncryptionData->m_nDerivedKeySize == xEncryptionData->m_aKey.getLength() )
+    {
+        // gpg4libre: no need to derive key, m_aKey is already
+        // usable as symmetric session key
+        aDerivedKey = xEncryptionData->m_aKey;
+    }
+    else if ( rtl_Digest_E_None != rtl_digest_PBKDF2( reinterpret_cast< sal_uInt8* >( aDerivedKey.getArray() ),
+                        aDerivedKey.getLength(),
+                        reinterpret_cast< const sal_uInt8 * > (xEncryptionData->m_aKey.getConstArray() ),
+                        xEncryptionData->m_aKey.getLength(),
+                        reinterpret_cast< const sal_uInt8 * > ( xEncryptionData->m_aSalt.getConstArray() ),
+                        xEncryptionData->m_aSalt.getLength(),
+                        xEncryptionData->m_nIterationCount ) )
+    {
+        throw ZipIOException("Can not create derived key!" );
+    }
+
+    if ( xEncryptionData->m_nEncAlg == xml::crypto::CipherID::AES_CBC_W3C_PADDING )
+    {
+        uno::Reference< uno::XComponentContext > xContext = xArgContext;
+        if ( !xContext.is() )
+            xContext = comphelper::getProcessComponentContext();
+
+        uno::Reference< xml::crypto::XNSSInitializer > xCipherContextSupplier = xml::crypto::NSSInitializer::create( xContext );
+
+        xResult = xCipherContextSupplier->getCipherContext( xEncryptionData->m_nEncAlg, aDerivedKey, xEncryptionData->m_aInitVector, bEncrypt, uno::Sequence< beans::NamedValue >() );
+    }
+    else if ( xEncryptionData->m_nEncAlg == xml::crypto::CipherID::BLOWFISH_CFB_8 )
+    {
+        xResult = BlowfishCFB8CipherContext::Create( aDerivedKey, xEncryptionData->m_aInitVector, bEncrypt );
+    }
+    else
+    {
+        throw ZipIOException("Unknown cipher algorithm is requested!" );
+    }
+
+    return xResult;
+}
+
+void ZipFile::StaticFillHeader( const ::rtl::Reference< EncryptionData >& rData,
+                                sal_Int64 nSize,
+                                const OUString& aMediaType,
+                                sal_Int8 * & pHeader )
+{
+    // I think it's safe to restrict vector and salt length to 2 bytes !
+    sal_Int16 nIVLength = static_cast < sal_Int16 > ( rData->m_aInitVector.getLength() );
+    sal_Int16 nSaltLength = static_cast < sal_Int16 > ( rData->m_aSalt.getLength() );
+    sal_Int16 nDigestLength = static_cast < sal_Int16 > ( rData->m_aDigest.getLength() );
+    sal_Int16 nMediaTypeLength = static_cast < sal_Int16 > ( aMediaType.getLength() * sizeof( sal_Unicode ) );
+
+    // First the header
+    *(pHeader++) = ( n_ConstHeader >> 0 ) & 0xFF;
+    *(pHeader++) = ( n_ConstHeader >> 8 ) & 0xFF;
+    *(pHeader++) = ( n_ConstHeader >> 16 ) & 0xFF;
+    *(pHeader++) = ( n_ConstHeader >> 24 ) & 0xFF;
+
+    // Then the version
+    *(pHeader++) = ( n_ConstCurrentVersion >> 0 ) & 0xFF;
+    *(pHeader++) = ( n_ConstCurrentVersion >> 8 ) & 0xFF;
+
+    // Then the iteration Count
+    sal_Int32 nIterationCount = rData->m_nIterationCount;
+    *(pHeader++) = static_cast< sal_Int8 >(( nIterationCount >> 0 ) & 0xFF);
+    *(pHeader++) = static_cast< sal_Int8 >(( nIterationCount >> 8 ) & 0xFF);
+    *(pHeader++) = static_cast< sal_Int8 >(( nIterationCount >> 16 ) & 0xFF);
+    *(pHeader++) = static_cast< sal_Int8 >(( nIterationCount >> 24 ) & 0xFF);
+
+    // FIXME64: need to handle larger sizes
+    // Then the size:
+    *(pHeader++) = static_cast< sal_Int8 >(( nSize >> 0 ) & 0xFF);
+    *(pHeader++) = static_cast< sal_Int8 >(( nSize >> 8 ) & 0xFF);
+    *(pHeader++) = static_cast< sal_Int8 >(( nSize >> 16 ) & 0xFF);
+    *(pHeader++) = static_cast< sal_Int8 >(( nSize >> 24 ) & 0xFF);
+
+    // Then the encryption algorithm
+    sal_Int32 nEncAlgID = rData->m_nEncAlg;
+    *(pHeader++) = static_cast< sal_Int8 >(( nEncAlgID >> 0 ) & 0xFF);
+    *(pHeader++) = static_cast< sal_Int8 >(( nEncAlgID >> 8 ) & 0xFF);
+    *(pHeader++) = static_cast< sal_Int8 >(( nEncAlgID >> 16 ) & 0xFF);
+    *(pHeader++) = static_cast< sal_Int8 >(( nEncAlgID >> 24 ) & 0xFF);
+
+    // Then the checksum algorithm
+    sal_Int32 nChecksumAlgID = rData->m_nCheckAlg;
+    *(pHeader++) = static_cast< sal_Int8 >(( nChecksumAlgID >> 0 ) & 0xFF);
+    *(pHeader++) = static_cast< sal_Int8 >(( nChecksumAlgID >> 8 ) & 0xFF);
+    *(pHeader++) = static_cast< sal_Int8 >(( nChecksumAlgID >> 16 ) & 0xFF);
+    *(pHeader++) = static_cast< sal_Int8 >(( nChecksumAlgID >> 24 ) & 0xFF);
+
+    // Then the derived key size
+    sal_Int32 nDerivedKeySize = rData->m_nDerivedKeySize;
+    *(pHeader++) = static_cast< sal_Int8 >(( nDerivedKeySize >> 0 ) & 0xFF);
+    *(pHeader++) = static_cast< sal_Int8 >(( nDerivedKeySize >> 8 ) & 0xFF);
+    *(pHeader++) = static_cast< sal_Int8 >(( nDerivedKeySize >> 16 ) & 0xFF);
+    *(pHeader++) = static_cast< sal_Int8 >(( nDerivedKeySize >> 24 ) & 0xFF);
+
+    // Then the start key generation algorithm
+    sal_Int32 nKeyAlgID = rData->m_nStartKeyGenID;
+    *(pHeader++) = static_cast< sal_Int8 >(( nKeyAlgID >> 0 ) & 0xFF);
+    *(pHeader++) = static_cast< sal_Int8 >(( nKeyAlgID >> 8 ) & 0xFF);
+    *(pHeader++) = static_cast< sal_Int8 >(( nKeyAlgID >> 16 ) & 0xFF);
+    *(pHeader++) = static_cast< sal_Int8 >(( nKeyAlgID >> 24 ) & 0xFF);
+
+    // Then the salt length
+    *(pHeader++) = static_cast< sal_Int8 >(( nSaltLength >> 0 ) & 0xFF);
+    *(pHeader++) = static_cast< sal_Int8 >(( nSaltLength >> 8 ) & 0xFF);
+
+    // Then the IV length
+    *(pHeader++) = static_cast< sal_Int8 >(( nIVLength >> 0 ) & 0xFF);
+    *(pHeader++) = static_cast< sal_Int8 >(( nIVLength >> 8 ) & 0xFF);
+
+    // Then the digest length
+    *(pHeader++) = static_cast< sal_Int8 >(( nDigestLength >> 0 ) & 0xFF);
+    *(pHeader++) = static_cast< sal_Int8 >(( nDigestLength >> 8 ) & 0xFF);
+
+    // Then the mediatype length
+    *(pHeader++) = static_cast< sal_Int8 >(( nMediaTypeLength >> 0 ) & 0xFF);
+    *(pHeader++) = static_cast< sal_Int8 >(( nMediaTypeLength >> 8 ) & 0xFF);
+
+    // Then the salt content
+    memcpy ( pHeader, rData->m_aSalt.getConstArray(), nSaltLength );
+    pHeader += nSaltLength;
+
+    // Then the IV content
+    memcpy ( pHeader, rData->m_aInitVector.getConstArray(), nIVLength );
+    pHeader += nIVLength;
+
+    // Then the digest content
+    memcpy ( pHeader, rData->m_aDigest.getConstArray(), nDigestLength );
+    pHeader += nDigestLength;
+
+    // Then the mediatype itself
+    memcpy ( pHeader, aMediaType.getStr(), nMediaTypeLength );
+    pHeader += nMediaTypeLength;
+}
+
+bool ZipFile::StaticFillData (  ::rtl::Reference< BaseEncryptionData > const & rData,
+                                    sal_Int32 &rEncAlg,
+                                    sal_Int32 &rChecksumAlg,
+                                    sal_Int32 &rDerivedKeySize,
+                                    sal_Int32 &rStartKeyGenID,
+                                    sal_Int32 &rSize,
+                                    OUString& aMediaType,
+                                    const uno::Reference< XInputStream >& rStream )
+{
+    bool bOk = false;
+    const sal_Int32 nHeaderSize = n_ConstHeaderSize - 4;
+    Sequence < sal_Int8 > aBuffer ( nHeaderSize );
+    if ( nHeaderSize == rStream->readBytes ( aBuffer, nHeaderSize ) )
+    {
+        sal_Int16 nPos = 0;
+        sal_Int8 *pBuffer = aBuffer.getArray();
+        sal_Int16 nVersion = pBuffer[nPos++] & 0xFF;
+        nVersion |= ( pBuffer[nPos++] & 0xFF ) << 8;
+        if ( nVersion == n_ConstCurrentVersion )
+        {
+            sal_Int32 nCount = pBuffer[nPos++] & 0xFF;
+            nCount |= ( pBuffer[nPos++] & 0xFF ) << 8;
+            nCount |= ( pBuffer[nPos++] & 0xFF ) << 16;
+            nCount |= ( pBuffer[nPos++] & 0xFF ) << 24;
+            rData->m_nIterationCount = nCount;
+
+            rSize  =   pBuffer[nPos++] & 0xFF;
+            rSize |= ( pBuffer[nPos++] & 0xFF ) << 8;
+            rSize |= ( pBuffer[nPos++] & 0xFF ) << 16;
+            rSize |= ( pBuffer[nPos++] & 0xFF ) << 24;
+
+            rEncAlg   =   pBuffer[nPos++] & 0xFF;
+            rEncAlg  |= ( pBuffer[nPos++] & 0xFF ) << 8;
+            rEncAlg  |= ( pBuffer[nPos++] & 0xFF ) << 16;
+            rEncAlg  |= ( pBuffer[nPos++] & 0xFF ) << 24;
+
+            rChecksumAlg   =   pBuffer[nPos++] & 0xFF;
+            rChecksumAlg  |= ( pBuffer[nPos++] & 0xFF ) << 8;
+            rChecksumAlg  |= ( pBuffer[nPos++] & 0xFF ) << 16;
+            rChecksumAlg  |= ( pBuffer[nPos++] & 0xFF ) << 24;
+
+            rDerivedKeySize   =   pBuffer[nPos++] & 0xFF;
+            rDerivedKeySize  |= ( pBuffer[nPos++] & 0xFF ) << 8;
+            rDerivedKeySize  |= ( pBuffer[nPos++] & 0xFF ) << 16;
+            rDerivedKeySize  |= ( pBuffer[nPos++] & 0xFF ) << 24;
+
+            rStartKeyGenID   =   pBuffer[nPos++] & 0xFF;
+            rStartKeyGenID  |= ( pBuffer[nPos++] & 0xFF ) << 8;
+            rStartKeyGenID  |= ( pBuffer[nPos++] & 0xFF ) << 16;
+            rStartKeyGenID  |= ( pBuffer[nPos++] & 0xFF ) << 24;
+
+            sal_Int16 nSaltLength =   pBuffer[nPos++] & 0xFF;
+            nSaltLength          |= ( pBuffer[nPos++] & 0xFF ) << 8;
+            sal_Int16 nIVLength   = ( pBuffer[nPos++] & 0xFF );
+            nIVLength            |= ( pBuffer[nPos++] & 0xFF ) << 8;
+            sal_Int16 nDigestLength = pBuffer[nPos++] & 0xFF;
+            nDigestLength        |= ( pBuffer[nPos++] & 0xFF ) << 8;
+
+            sal_Int16 nMediaTypeLength = pBuffer[nPos++] & 0xFF;
+            nMediaTypeLength |= ( pBuffer[nPos++] & 0xFF ) << 8;
+
+            if ( nSaltLength == rStream->readBytes ( aBuffer, nSaltLength ) )
+            {
+                rData->m_aSalt.realloc ( nSaltLength );
+                memcpy ( rData->m_aSalt.getArray(), aBuffer.getConstArray(), nSaltLength );
+                if ( nIVLength == rStream->readBytes ( aBuffer, nIVLength ) )
+                {
+                    rData->m_aInitVector.realloc ( nIVLength );
+                    memcpy ( rData->m_aInitVector.getArray(), aBuffer.getConstArray(), nIVLength );
+                    if ( nDigestLength == rStream->readBytes ( aBuffer, nDigestLength ) )
+                    {
+                        rData->m_aDigest.realloc ( nDigestLength );
+                        memcpy ( rData->m_aDigest.getArray(), aBuffer.getConstArray(), nDigestLength );
+
+                        if ( nMediaTypeLength == rStream->readBytes ( aBuffer, nMediaTypeLength ) )
+                        {
+                            aMediaType = OUString( reinterpret_cast<sal_Unicode const *>(aBuffer.getConstArray()),
+                                                            nMediaTypeLength / sizeof( sal_Unicode ) );
+                            bOk = true;
+                        }
+                    }
+                }
+            }
+        }
+    }
+    return bOk;
+}
+
+uno::Reference< XInputStream > ZipFile::StaticGetDataFromRawStream( const rtl::Reference< comphelper::RefCountedMutex >& aMutexHolder,
+                                                                const uno::Reference< uno::XComponentContext >& rxContext,
+                                                                const uno::Reference< XInputStream >& xStream,
+                                                                const ::rtl::Reference< EncryptionData > &rData )
+{
+    if ( !rData.is() )
+        throw ZipIOException("Encrypted stream without encryption data!" );
+
+    if ( !rData->m_aKey.hasElements() )
+        throw packages::WrongPasswordException(THROW_WHERE );
+
+    uno::Reference< XSeekable > xSeek( xStream, UNO_QUERY );
+    if ( !xSeek.is() )
+        throw ZipIOException("The stream must be seekable!" );
+
+    // if we have a digest, then this file is an encrypted one and we should
+    // check if we can decrypt it or not
+    OSL_ENSURE( rData->m_aDigest.hasElements(), "Can't detect password correctness without digest!" );
+    if ( rData->m_aDigest.hasElements() )
+    {
+        sal_Int32 nSize = sal::static_int_cast< sal_Int32 >( xSeek->getLength() );
+        if ( nSize > n_ConstDigestLength + 32 )
+            nSize = n_ConstDigestLength + 32;
+
+        // skip header
+        xSeek->seek( n_ConstHeaderSize + rData->m_aInitVector.getLength() +
+                                rData->m_aSalt.getLength() + rData->m_aDigest.getLength() );
+
+        // Only want to read enough to verify the digest
+        Sequence < sal_Int8 > aReadBuffer ( nSize );
+
+        xStream->readBytes( aReadBuffer, nSize );
+
+        if ( !StaticHasValidPassword( rxContext, aReadBuffer, rData ) )
+            throw packages::WrongPasswordException(THROW_WHERE );
+    }
+
+    return new XUnbufferedStream( aMutexHolder, xStream, rData );
+}
+
+#if 0
+// for debugging purposes
+void CheckSequence( const uno::Sequence< sal_Int8 >& aSequence )
+{
+    if ( aSequence.getLength() )
+    {
+        sal_Int32* pPointer = *( (sal_Int32**)&aSequence );
+        sal_Int32 nSize = *( pPointer + 1 );
+        sal_Int32 nMemSize = *( pPointer - 2 );
+        sal_Int32 nUsedMemSize = ( nSize + 4 * sizeof( sal_Int32 ) );
+        OSL_ENSURE( nSize == aSequence.getLength() && nUsedMemSize + 7 - ( nUsedMemSize - 1 ) % 8 == nMemSize, "Broken Sequence!" );
+    }
+}
+#endif
+
+bool ZipFile::StaticHasValidPassword( const uno::Reference< uno::XComponentContext >& rxContext, const Sequence< sal_Int8 > &aReadBuffer, const ::rtl::Reference< EncryptionData > &rData )
+{
+    if ( !rData.is() || !rData->m_aKey.hasElements() )
+        return false;
+
+    bool bRet = false;
+
+    uno::Reference< xml::crypto::XCipherContext > xCipher( StaticGetCipher( rxContext, rData, false ), uno::UNO_SET_THROW );
+
+    uno::Sequence< sal_Int8 > aDecryptBuffer;
+    uno::Sequence< sal_Int8 > aDecryptBuffer2;
+    try
+    {
+        aDecryptBuffer = xCipher->convertWithCipherContext( aReadBuffer );
+        aDecryptBuffer2 = xCipher->finalizeCipherContextAndDispose();
+    }
+    catch( uno::Exception& )
+    {
+        // decryption with padding will throw the exception in finalizing if the buffer represent only part of the stream
+        // it is no problem, actually this is why we read 32 additional bytes ( two of maximal possible encryption blocks )
+    }
+
+    if ( aDecryptBuffer2.hasElements() )
+    {
+        sal_Int32 nOldLen = aDecryptBuffer.getLength();
+        aDecryptBuffer.realloc( nOldLen + aDecryptBuffer2.getLength() );
+        memcpy( aDecryptBuffer.getArray() + nOldLen, aDecryptBuffer2.getConstArray(), aDecryptBuffer2.getLength() );
+    }
+
+    if ( aDecryptBuffer.getLength() > n_ConstDigestLength )
+        aDecryptBuffer.realloc( n_ConstDigestLength );
+
+    uno::Sequence< sal_Int8 > aDigestSeq;
+    uno::Reference< xml::crypto::XDigestContext > xDigestContext( StaticGetDigestContextForChecksum( rxContext, rData ), uno::UNO_SET_THROW );
+
+    xDigestContext->updateDigest( aDecryptBuffer );
+    aDigestSeq = xDigestContext->finalizeDigestAndDispose();
+
+    // If we don't have a digest, then we have to assume that the password is correct
+    if (  rData->m_aDigest.hasElements() &&
+          ( aDigestSeq.getLength() != rData->m_aDigest.getLength() ||
+            0 != memcmp ( aDigestSeq.getConstArray(),
+                                     rData->m_aDigest.getConstArray(),
+                                    aDigestSeq.getLength() ) ) )
+    {
+        // We should probably tell the user that the password they entered was wrong
+    }
+    else
+        bRet = true;
+
+    return bRet;
+}
+
+bool ZipFile::hasValidPassword ( ZipEntry const & rEntry, const ::rtl::Reference< EncryptionData >& rData )
+{
+    ::osl::MutexGuard aGuard( m_aMutexHolder->GetMutex() );
+
+    bool bRet = false;
+    if ( rData.is() && rData->m_aKey.hasElements() )
+    {
+        css::uno::Reference < css::io::XSeekable > xSeek(xStream, UNO_QUERY_THROW);
+        xSeek->seek( rEntry.nOffset );
+        sal_Int64 nSize = rEntry.nMethod == DEFLATED ? rEntry.nCompressedSize : rEntry.nSize;
+
+        // Only want to read enough to verify the digest
+        if ( nSize > n_ConstDigestDecrypt )
+            nSize = n_ConstDigestDecrypt;
+
+        Sequence < sal_Int8 > aReadBuffer ( nSize );
+
+        xStream->readBytes( aReadBuffer, nSize );
+
+        bRet = StaticHasValidPassword( m_xContext, aReadBuffer, rData );
+    }
+
+    return bRet;
+}
+
+namespace {
+
+class XBufferedStream : public cppu::WeakImplHelper<css::io::XInputStream, css::io::XSeekable>
+{
+    std::vector<sal_Int8> maBytes;
+    size_t mnPos;
+
+    size_t remainingSize() const
+    {
+        return maBytes.size() - mnPos;
+    }
+
+    bool hasBytes() const
+    {
+        return mnPos < maBytes.size();
+    }
+
+public:
+    XBufferedStream( const uno::Reference<XInputStream>& xSrcStream ) : mnPos(0)
+    {
+        sal_Int32 nRemaining = xSrcStream->available();
+        uno::Reference< css::lang::XUnoTunnel > xInputTunnel( xSrcStream, uno::UNO_QUERY );
+        comphelper::ByteReader* pByteReader = nullptr;
+        if (xInputTunnel)
+            pByteReader = reinterpret_cast< comphelper::ByteReader* >( xInputTunnel->getSomething( comphelper::ByteReader::getUnoTunnelId() ) );
+
+        if (pByteReader)
+        {
+            maBytes.resize(nRemaining);
+
+            sal_Int8* pData = maBytes.data();
+            while (nRemaining > 0)
+            {
+                sal_Int32 nRead = pByteReader->readSomeBytes(pData, nRemaining);
+                nRemaining -= nRead;
+                pData += nRead;
+            }
+        }
+        else
+        {
+            const sal_Int32 nBufSize = 8192;
+
+            sal_Int32 nRead = 0;
+            maBytes.reserve(nRemaining);
+            uno::Sequence<sal_Int8> aBuf(nBufSize);
+
+            auto readAndCopy = [&]( sal_Int32 nReadSize ) -> sal_Int32
+            {
+                sal_Int32 nBytes = xSrcStream->readBytes(aBuf, nReadSize);
+                const sal_Int8* p = aBuf.getConstArray();
+                const sal_Int8* pEnd = p + nBytes;
+                maBytes.insert( maBytes.end(), p, pEnd );
+                return nBytes;
+            };
+
+            while (nRemaining > nBufSize)
+            {
+                const auto nBytes = readAndCopy(nBufSize);
+                if (!nBytes)
+                    break;
+                nRead += nBytes;
+                nRemaining -= nBytes;
+            }
+
+            if (nRemaining)
+                nRead += readAndCopy(nRemaining);
+            maBytes.resize(nRead);
+        }
+    }
+
+    virtual sal_Int32 SAL_CALL readBytes( uno::Sequence<sal_Int8>& rData, sal_Int32 nBytesToRead ) override
+    {
+        if (!hasBytes())
+            return 0;
+
+        sal_Int32 nReadSize = std::min<sal_Int32>(nBytesToRead, remainingSize());
+        rData.realloc(nReadSize);
+        auto pData = rData.getArray();
+        std::vector<sal_Int8>::const_iterator it = maBytes.cbegin();
+        std::advance(it, mnPos);
+        for (sal_Int32 i = 0; i < nReadSize; ++i, ++it)
+            pData[i] = *it;
+
+        mnPos += nReadSize;
+
+        return nReadSize;
+    }
+
+    virtual sal_Int32 SAL_CALL readSomeBytes( ::css::uno::Sequence<sal_Int8>& rData, sal_Int32 nMaxBytesToRead ) override
+    {
+        return readBytes(rData, nMaxBytesToRead);
+    }
+
+    virtual void SAL_CALL skipBytes( sal_Int32 nBytesToSkip ) override
+    {
+        if (!hasBytes())
+            return;
+
+        mnPos += nBytesToSkip;
+    }
+
+    virtual sal_Int32 SAL_CALL available() override
+    {
+        if (!hasBytes())
+            return 0;
+
+        return remainingSize();
+    }
+
+    virtual void SAL_CALL closeInput() override
+    {
+    }
+    // XSeekable
+    virtual void SAL_CALL seek( sal_Int64 location ) override
+    {
+        if ( location < 0 || o3tl::make_unsigned(location) > maBytes.size() )
+            throw IllegalArgumentException(THROW_WHERE, uno::Reference< uno::XInterface >(), 1 );
+        mnPos = location;
+    }
+    virtual sal_Int64 SAL_CALL getPosition() override
+    {
+        return mnPos;
+    }
+    virtual sal_Int64 SAL_CALL getLength() override
+    {
+        return maBytes.size();
+    }
+};
+
+}
+
+uno::Reference< XInputStream > ZipFile::createStreamForZipEntry(
+            const rtl::Reference< comphelper::RefCountedMutex >& aMutexHolder,
+            ZipEntry const & rEntry,
+            const ::rtl::Reference< EncryptionData > &rData,
+            sal_Int8 nStreamMode,
+            bool bIsEncrypted,
+            const bool bUseBufferedStream,
+            const OUString& aMediaType )
+{
+    ::osl::MutexGuard aGuard( m_aMutexHolder->GetMutex() );
+
+    rtl::Reference< XUnbufferedStream > xSrcStream = new XUnbufferedStream(
+        m_xContext, aMutexHolder, rEntry, xStream, rData, nStreamMode, bIsEncrypted, aMediaType, bRecoveryMode);
+
+    if (!bUseBufferedStream)
+        return xSrcStream;
+
+    uno::Reference<io::XInputStream> xBufStream;
+#ifndef EMSCRIPTEN
+    static const sal_Int32 nThreadingThreshold = 10000;
+
+    if( xSrcStream->available() > nThreadingThreshold )
+        xBufStream = new XBufferedThreadedStream(xSrcStream, xSrcStream->getSize());
+    else
+#endif
+        xBufStream = new XBufferedStream(xSrcStream);
+
+    return xBufStream;
+}
+
+ZipEnumeration ZipFile::entries()
+{
+    return aEntries;
+}
+
+uno::Reference< XInputStream > ZipFile::getInputStream( ZipEntry& rEntry,
+        const ::rtl::Reference< EncryptionData > &rData,
+        bool bIsEncrypted,
+        const rtl::Reference<comphelper::RefCountedMutex>& aMutexHolder )
+{
+    ::osl::MutexGuard aGuard( m_aMutexHolder->GetMutex() );
+
+    if ( rEntry.nOffset <= 0 )
+        readLOC( rEntry );
+
+    // We want to return a rawStream if we either don't have a key or if the
+    // key is wrong
+
+    bool bNeedRawStream = rEntry.nMethod == STORED;
+
+    // if we have a digest, then this file is an encrypted one and we should
+    // check if we can decrypt it or not
+    if ( bIsEncrypted && rData.is() && rData->m_aDigest.hasElements() )
+        bNeedRawStream = !hasValidPassword ( rEntry, rData );
+
+    return createStreamForZipEntry ( aMutexHolder,
+                                    rEntry,
+                                    rData,
+                                    bNeedRawStream ? UNBUFF_STREAM_RAW : UNBUFF_STREAM_DATA,
+                                    bIsEncrypted );
+}
+
+uno::Reference< XInputStream > ZipFile::getDataStream( ZipEntry& rEntry,
+        const ::rtl::Reference< EncryptionData > &rData,
+        bool bIsEncrypted,
+        const rtl::Reference<comphelper::RefCountedMutex>& aMutexHolder )
+{
+    ::osl::MutexGuard aGuard( m_aMutexHolder->GetMutex() );
+
+    if ( rEntry.nOffset <= 0 )
+        readLOC( rEntry );
+
+    // An exception must be thrown in case stream is encrypted and
+    // there is no key or the key is wrong
+    bool bNeedRawStream = false;
+    if ( bIsEncrypted )
+    {
+        // in case no digest is provided there is no way
+        // to detect password correctness
+        if ( !rData.is() )
+            throw ZipException("Encrypted stream without encryption data!" );
+
+        // if we have a digest, then this file is an encrypted one and we should
+        // check if we can decrypt it or not
+        OSL_ENSURE( rData->m_aDigest.hasElements(), "Can't detect password correctness without digest!" );
+        if ( rData->m_aDigest.hasElements() && !hasValidPassword ( rEntry, rData ) )
+                throw packages::WrongPasswordException(THROW_WHERE );
+    }
+    else
+        bNeedRawStream = ( rEntry.nMethod == STORED );
+
+    return createStreamForZipEntry ( aMutexHolder,
+                                    rEntry,
+                                    rData,
+                                    bNeedRawStream ? UNBUFF_STREAM_RAW : UNBUFF_STREAM_DATA,
+                                    bIsEncrypted );
+}
+
+uno::Reference< XInputStream > ZipFile::getRawData( ZipEntry& rEntry,
+        const ::rtl::Reference< EncryptionData >& rData,
+        bool bIsEncrypted,
+        const rtl::Reference<comphelper::RefCountedMutex>& aMutexHolder,
+        const bool bUseBufferedStream )
+{
+    ::osl::MutexGuard aGuard( m_aMutexHolder->GetMutex() );
+
+    if ( rEntry.nOffset <= 0 )
+        readLOC( rEntry );
+
+    return createStreamForZipEntry ( aMutexHolder, rEntry, rData, UNBUFF_STREAM_RAW, bIsEncrypted, bUseBufferedStream );
+}
+
+uno::Reference< XInputStream > ZipFile::getWrappedRawStream(
+        ZipEntry& rEntry,
+        const ::rtl::Reference< EncryptionData >& rData,
+        const OUString& aMediaType,
+        const rtl::Reference<comphelper::RefCountedMutex>& aMutexHolder )
+{
+    ::osl::MutexGuard aGuard( m_aMutexHolder->GetMutex() );
+
+    if ( !rData.is() )
+        throw packages::NoEncryptionException(THROW_WHERE );
+
+    if ( rEntry.nOffset <= 0 )
+        readLOC( rEntry );
+
+    return createStreamForZipEntry ( aMutexHolder, rEntry, rData, UNBUFF_STREAM_WRAPPEDRAW, true, true, aMediaType );
+}
+
+void ZipFile::readLOC( ZipEntry &rEntry )
+{
+    ::osl::MutexGuard aGuard( m_aMutexHolder->GetMutex() );
+
+    sal_Int64 nPos = -rEntry.nOffset;
+
+    aGrabber.seek(nPos);
+    sal_Int32 nTestSig = aGrabber.ReadInt32();
+    if (nTestSig != LOCSIG)
+        throw ZipIOException("Invalid LOC header (bad signature)" );
+
+    // Ignore all (duplicated) information from the local file header.
+    // various programs produced "broken" zip files; even LO at some point.
+    // Just verify the path and calculate the data offset and otherwise
+    // rely on the central directory info.
+
+    aGrabber.ReadInt16(); //version
+    aGrabber.ReadInt16(); //flag
+    aGrabber.ReadInt16(); //how
+    aGrabber.ReadInt32(); //time
+    aGrabber.ReadInt32(); //crc
+    aGrabber.ReadInt32(); //compressed size
+    aGrabber.ReadInt32(); //size
+    sal_Int16 nPathLen = aGrabber.ReadInt16();
+    sal_Int16 nExtraLen = aGrabber.ReadInt16();
+    rEntry.nOffset = aGrabber.getPosition() + nPathLen + nExtraLen;
+
+    // FIXME64: need to read 64bit LOC
+
+    bool bBroken = false;
+
+    try
+    {
+        sal_Int16 nPathLenToRead = nPathLen;
+        const sal_Int64 nBytesAvailable = aGrabber.getLength() - aGrabber.getPosition();
+        if (nPathLenToRead > nBytesAvailable)
+            nPathLenToRead = nBytesAvailable;
+        else if (nPathLenToRead < 0)
+            nPathLenToRead = 0;
+
+        // read always in UTF8, some tools seem not to set UTF8 bit
+        uno::Sequence<sal_Int8> aNameBuffer(nPathLenToRead);
+        sal_Int32 nRead = aGrabber.readBytes(aNameBuffer, nPathLenToRead);
+        if (nRead < aNameBuffer.getLength())
+            aNameBuffer.realloc(nRead);
+
+        OUString sLOCPath( reinterpret_cast<const char *>(aNameBuffer.getConstArray()),
+                           aNameBuffer.getLength(),
+                           RTL_TEXTENCODING_UTF8 );
+
+        if ( rEntry.nPathLen == -1 ) // the file was created
+        {
+            rEntry.nPathLen = nPathLen;
+            rEntry.sPath = sLOCPath;
+        }
+
+        bBroken = rEntry.nPathLen != nPathLen
+                        || rEntry.sPath != sLOCPath;
+    }
+    catch(...)
+    {
+        bBroken = true;
+    }
+
+    if ( bBroken && !bRecoveryMode )
+        throw ZipIOException("The stream seems to be broken!" );
+}
+
+sal_Int32 ZipFile::findEND()
+{
+    // this method is called in constructor only, no need for mutex
+    sal_Int32 nPos, nEnd;
+    Sequence < sal_Int8 > aBuffer;
+    try
+    {
+        sal_Int32 nLength = static_cast <sal_Int32 > (aGrabber.getLength());
+        if (nLength < ENDHDR)
+            return -1;
+        nPos = nLength - ENDHDR - ZIP_MAXNAMELEN;
+        nEnd = nPos >= 0 ? nPos : 0 ;
+
+        aGrabber.seek( nEnd );
+
+        auto nSize = nLength - nEnd;
+        if (nSize != aGrabber.readBytes(aBuffer, nSize))
+            throw ZipException("Zip END signature not found!" );
+
+        const sal_Int8 *pBuffer = aBuffer.getConstArray();
+
+        nPos = nSize - ENDHDR;
+        while ( nPos >= 0 )
+        {
+            if (pBuffer[nPos] == 'P' && pBuffer[nPos+1] == 'K' && pBuffer[nPos+2] == 5 && pBuffer[nPos+3] == 6 )
+                return nPos + nEnd;
+            nPos--;
+        }
+    }
+    catch ( IllegalArgumentException& )
+    {
+        throw ZipException("Zip END signature not found!" );
+    }
+    catch ( NotConnectedException& )
+    {
+        throw ZipException("Zip END signature not found!" );
+    }
+    catch ( BufferSizeExceededException& )
+    {
+        throw ZipException("Zip END signature not found!" );
+    }
+    throw ZipException("Zip END signature not found!" );
+}
+
+sal_Int32 ZipFile::readCEN()
+{
+    // this method is called in constructor only, no need for mutex
+    sal_Int32 nCenPos = -1, nLocPos;
+    sal_uInt16 nCount;
+
+    try
+    {
+        sal_Int32 nEndPos = findEND();
+        if (nEndPos == -1)
+            return -1;
+        aGrabber.seek(nEndPos + ENDTOT);
+        sal_uInt16 nTotal = aGrabber.ReadUInt16();
+        sal_Int32 nCenLen = aGrabber.ReadInt32();
+        sal_Int32 nCenOff = aGrabber.ReadInt32();
+
+        if ( nTotal * CENHDR > nCenLen )
+            throw ZipException("invalid END header (bad entry count)" );
+
+        if ( nTotal > ZIP_MAXENTRIES )
+            throw ZipException("too many entries in ZIP File" );
+
+        if ( nCenLen < 0 || nCenLen > nEndPos )
+            throw ZipException("Invalid END header (bad central directory size)" );
+
+        nCenPos = nEndPos - nCenLen;
+
+        if ( nCenOff < 0 || nCenOff > nCenPos )
+            throw ZipException("Invalid END header (bad central directory size)" );
+
+        nLocPos = nCenPos - nCenOff;
+        aGrabber.seek( nCenPos );
+        Sequence < sal_Int8 > aCENBuffer ( nCenLen );
+        sal_Int64 nRead = aGrabber.readBytes ( aCENBuffer, nCenLen );
+        if ( static_cast < sal_Int64 > ( nCenLen ) != nRead )
+            throw ZipException ("Error reading CEN into memory buffer!" );
+
+        MemoryByteGrabber aMemGrabber(aCENBuffer);
+
+        ZipEntry aEntry;
+        sal_Int16 nCommentLen;
+
+        aEntries.reserve(nTotal);
+        for (nCount = 0 ; nCount < nTotal; nCount++)
+        {
+            sal_Int32 nTestSig = aMemGrabber.ReadInt32();
+            if ( nTestSig != CENSIG )
+                throw ZipException("Invalid CEN header (bad signature)" );
+
+            aMemGrabber.skipBytes ( 2 );
+            aEntry.nVersion = aMemGrabber.ReadInt16();
+            aEntry.nFlag = aMemGrabber.ReadInt16();
+
+            if ( ( aEntry.nFlag & 1 ) == 1 )
+                throw ZipException("Invalid CEN header (encrypted entry)" );
+
+            aEntry.nMethod = aMemGrabber.ReadInt16();
+
+            if ( aEntry.nMethod != STORED && aEntry.nMethod != DEFLATED)
+                throw ZipException("Invalid CEN header (bad compression method)" );
+
+            aEntry.nTime = aMemGrabber.ReadInt32();
+            aEntry.nCrc = aMemGrabber.ReadInt32();
+
+            sal_uInt32 nCompressedSize = aMemGrabber.ReadUInt32();
+            sal_uInt32 nSize = aMemGrabber.ReadUInt32();
+            aEntry.nPathLen = aMemGrabber.ReadInt16();
+            aEntry.nExtraLen = aMemGrabber.ReadInt16();
+            nCommentLen = aMemGrabber.ReadInt16();
+            aMemGrabber.skipBytes ( 8 );
+            sal_uInt32 nOffset = aMemGrabber.ReadUInt32();
+
+            // FIXME64: need to read the 64bit header instead
+            if ( nSize == 0xffffffff ||
+                 nOffset == 0xffffffff ||
+                 nCompressedSize == 0xffffffff ) {
+                throw ZipException("PK64 zip file entry" );
+            }
+            aEntry.nCompressedSize = nCompressedSize;
+            aEntry.nSize = nSize;
+            aEntry.nOffset = nOffset;
+
+            aEntry.nOffset += nLocPos;
+            aEntry.nOffset *= -1;
+
+            if ( aEntry.nPathLen < 0 )
+                throw ZipException("unexpected name length" );
+
+            if ( nCommentLen < 0 )
+                throw ZipException("unexpected comment length" );
+
+            if ( aEntry.nExtraLen < 0 )
+                throw ZipException("unexpected extra header info length" );
+
+            if (aEntry.nPathLen > aMemGrabber.remainingSize())
+                throw ZipException("name too long");
+
+            // read always in UTF8, some tools seem not to set UTF8 bit
+            aEntry.sPath = OUString( reinterpret_cast<char const *>(aMemGrabber.getCurrentPos()),
+                                     aEntry.nPathLen,
+                                     RTL_TEXTENCODING_UTF8 );
+
+            if ( !::comphelper::OStorageHelper::IsValidZipEntryFileName( aEntry.sPath, true ) )
+                throw ZipException("Zip entry has an invalid name." );
+
+            aMemGrabber.skipBytes( aEntry.nPathLen + aEntry.nExtraLen + nCommentLen );
+            aEntries[aEntry.sPath] = aEntry;
+        }
+
+        if (nCount != nTotal)
+            throw ZipException("Count != Total" );
+    }
+    catch ( IllegalArgumentException & )
+    {
+        // seek can throw this...
+        nCenPos = -1; // make sure we return -1 to indicate an error
+    }
+    return nCenPos;
+}
+
+void ZipFile::recover()
+{
+    ::osl::MutexGuard aGuard( m_aMutexHolder->GetMutex() );
+
+    sal_Int64 nLength;
+    Sequence < sal_Int8 > aBuffer;
+
+    try
+    {
+        nLength = aGrabber.getLength();
+        if (nLength < ENDHDR)
+            return;
+
+        aGrabber.seek( 0 );
+
+        const sal_Int64 nToRead = 32000;
+        for( sal_Int64 nGenPos = 0; aGrabber.readBytes( aBuffer, nToRead ) && aBuffer.getLength() > 16; )
+        {
+            const sal_Int8 *pBuffer = aBuffer.getConstArray();
+            sal_Int32 nBufSize = aBuffer.getLength();
+
+            sal_Int64 nPos = 0;
+            // the buffer should contain at least one header,
+            // or if it is end of the file, at least the postheader with sizes and hash
+            while( nPos < nBufSize - 30
+                || ( nBufSize < nToRead && nPos < nBufSize - 16 ) )
+
+            {
+                if ( nPos < nBufSize - 30 && pBuffer[nPos] == 'P' && pBuffer[nPos+1] == 'K' && pBuffer[nPos+2] == 3 && pBuffer[nPos+3] == 4 )
+                {
+                    ZipEntry aEntry;
+                    Sequence<sal_Int8> aTmpBuffer(&(pBuffer[nPos+4]), 26);
+                    MemoryByteGrabber aMemGrabber(aTmpBuffer);
+
+                    aEntry.nVersion = aMemGrabber.ReadInt16();
+                    aEntry.nFlag = aMemGrabber.ReadInt16();
+
+                    if ( ( aEntry.nFlag & 1 ) != 1 )
+                    {
+                        aEntry.nMethod = aMemGrabber.ReadInt16();
+
+                        if ( aEntry.nMethod == STORED || aEntry.nMethod == DEFLATED )
+                        {
+                            aEntry.nTime = aMemGrabber.ReadInt32();
+                            aEntry.nCrc = aMemGrabber.ReadInt32();
+                            sal_uInt32 nCompressedSize = aMemGrabber.ReadUInt32();
+                            sal_uInt32 nSize = aMemGrabber.ReadUInt32();
+                            aEntry.nPathLen = aMemGrabber.ReadInt16();
+                            aEntry.nExtraLen = aMemGrabber.ReadInt16();
+
+                            // FIXME64: need to read the 64bit header instead
+                            if ( nSize == 0xffffffff ||
+                                 nCompressedSize == 0xffffffff ) {
+                                throw ZipException("PK64 zip file entry" );
+                            }
+                            aEntry.nCompressedSize = nCompressedSize;
+                            aEntry.nSize = nSize;
+
+                            sal_Int32 nDescrLength =
+                                ( aEntry.nMethod == DEFLATED && ( aEntry.nFlag & 8 ) ) ? 16 : 0;
+
+                            sal_Int64 nDataSize = ( aEntry.nMethod == DEFLATED ) ? aEntry.nCompressedSize : aEntry.nSize;
+                            sal_Int64 nBlockLength = nDataSize + aEntry.nPathLen + aEntry.nExtraLen + 30 + nDescrLength;
+                            if ( aEntry.nPathLen >= 0 && aEntry.nExtraLen >= 0
+                                && ( nGenPos + nPos + nBlockLength ) <= nLength )
+                            {
+                                // read always in UTF8, some tools seem not to set UTF8 bit
+                                if( nPos + 30 + aEntry.nPathLen <= nBufSize )
+                                    aEntry.sPath = OUString ( reinterpret_cast<char const *>(&pBuffer[nPos + 30]),
+                                                              aEntry.nPathLen,
+                                                              RTL_TEXTENCODING_UTF8 );
+                                else
+                                {
+                                    Sequence < sal_Int8 > aFileName;
+                                    aGrabber.seek( nGenPos + nPos + 30 );
+                                    aGrabber.readBytes( aFileName, aEntry.nPathLen );
+                                    aEntry.sPath = OUString ( reinterpret_cast<const char *>(aFileName.getConstArray()),
+                                                              aFileName.getLength(),
+                                                              RTL_TEXTENCODING_UTF8 );
+                                    aEntry.nPathLen = static_cast< sal_Int16 >(aFileName.getLength());
+                                }
+
+                                aEntry.nOffset = nGenPos + nPos + 30 + aEntry.nPathLen + aEntry.nExtraLen;
+
+                                if ( ( aEntry.nSize || aEntry.nCompressedSize ) && !checkSizeAndCRC( aEntry ) )
+                                {
+                                    aEntry.nCrc = 0;
+                                    aEntry.nCompressedSize = 0;
+                                    aEntry.nSize = 0;
+                                }
+
+                                aEntries.emplace( aEntry.sPath, aEntry );
+                            }
+                        }
+                    }
+
+                    nPos += 4;
+                }
+                else if (pBuffer[nPos] == 'P' && pBuffer[nPos+1] == 'K' && pBuffer[nPos+2] == 7 && pBuffer[nPos+3] == 8 )
+                {
+                    sal_Int64 nCompressedSize, nSize;
+                    Sequence<sal_Int8> aTmpBuffer(&(pBuffer[nPos+4]), 12);
+                    MemoryByteGrabber aMemGrabber(aTmpBuffer);
+                    sal_Int32 nCRC32 = aMemGrabber.ReadInt32();
+                    sal_uInt32 nCompressedSize32 = aMemGrabber.ReadUInt32();
+                    sal_uInt32 nSize32 = aMemGrabber.ReadUInt32();
+
+                    // FIXME64: work to be done here ...
+                    nCompressedSize = nCompressedSize32;
+                    nSize = nSize32;
+
+                    for( auto& rEntry : aEntries )
+                    {
+                        // this is a broken package, accept this block not only for DEFLATED streams
+                        if( rEntry.second.nFlag & 8 )
+                        {
+                            sal_Int64 nStreamOffset = nGenPos + nPos - nCompressedSize;
+                            if ( nStreamOffset == rEntry.second.nOffset && nCompressedSize > rEntry.second.nCompressedSize )
+                            {
+                                // only DEFLATED blocks need to be checked
+                                bool bAcceptBlock = ( rEntry.second.nMethod == STORED && nCompressedSize == nSize );
+
+                                if ( !bAcceptBlock )
+                                {
+                                    sal_Int64 nRealSize = 0;
+                                    sal_Int32 nRealCRC = 0;
+                                    getSizeAndCRC( nStreamOffset, nCompressedSize, &nRealSize, &nRealCRC );
+                                    bAcceptBlock = ( nRealSize == nSize && nRealCRC == nCRC32 );
+                                }
+
+                                if ( bAcceptBlock )
+                                {
+                                    rEntry.second.nCrc = nCRC32;
+                                    rEntry.second.nCompressedSize = nCompressedSize;
+                                    rEntry.second.nSize = nSize;
+                                }
+                            }
+#if 0
+// for now ignore clearly broken streams
+                            else if( !rEntry.second.nCompressedSize )
+                            {
+                                rEntry.second.nCrc = nCRC32;
+                                sal_Int32 nRealStreamSize = nGenPos + nPos - rEntry.second.nOffset;
+                                rEntry.second.nCompressedSize = nRealStreamSize;
+                                rEntry.second.nSize = nSize;
+                            }
+#endif
+                        }
+                    }
+
+                    nPos += 4;
+                }
+                else
+                    nPos++;
+            }
+
+            nGenPos += nPos;
+            aGrabber.seek( nGenPos );
+        }
+    }
+    catch ( IllegalArgumentException& )
+    {
+        throw ZipException("Zip END signature not found!" );
+    }
+    catch ( NotConnectedException& )
+    {
+        throw ZipException("Zip END signature not found!" );
+    }
+    catch ( BufferSizeExceededException& )
+    {
+        throw ZipException("Zip END signature not found!" );
+    }
+}
+
+bool ZipFile::checkSizeAndCRC( const ZipEntry& aEntry )
+{
+    ::osl::MutexGuard aGuard( m_aMutexHolder->GetMutex() );
+
+    sal_Int32 nCRC = 0;
+    sal_Int64 nSize = 0;
+
+    if( aEntry.nMethod == STORED )
+        return ( getCRC( aEntry.nOffset, aEntry.nSize ) == aEntry.nCrc );
+
+    getSizeAndCRC( aEntry.nOffset, aEntry.nCompressedSize, &nSize, &nCRC );
+    return ( aEntry.nSize == nSize && aEntry.nCrc == nCRC );
+}
+
+sal_Int32 ZipFile::getCRC( sal_Int64 nOffset, sal_Int64 nSize )
+{
+    ::osl::MutexGuard aGuard( m_aMutexHolder->GetMutex() );
+
+    Sequence < sal_Int8 > aBuffer;
+    CRC32 aCRC;
+    sal_Int64 nBlockSize = ::std::min(nSize, static_cast< sal_Int64 >(32000));
+
+    aGrabber.seek( nOffset );
+    for (sal_Int64 ind = 0;
+         aGrabber.readBytes( aBuffer, nBlockSize ) && ind * nBlockSize < nSize;
+         ++ind)
+    {
+        sal_Int64 nLen = ::std::min(nBlockSize, nSize - ind * nBlockSize);
+        aCRC.updateSegment(aBuffer, static_cast<sal_Int32>(nLen));
+    }
+
+    return aCRC.getValue();
+}
+
+void ZipFile::getSizeAndCRC( sal_Int64 nOffset, sal_Int64 nCompressedSize, sal_Int64 *nSize, sal_Int32 *nCRC )
+{
+    ::osl::MutexGuard aGuard( m_aMutexHolder->GetMutex() );
+
+    Sequence < sal_Int8 > aBuffer;
+    CRC32 aCRC;
+    sal_Int64 nRealSize = 0;
+    Inflater aInflaterLocal( true );
+    sal_Int32 nBlockSize = static_cast< sal_Int32 > (::std::min( nCompressedSize, static_cast< sal_Int64 >( 32000 ) ) );
+
+    aGrabber.seek( nOffset );
+    for ( sal_Int64 ind = 0;
+          !aInflaterLocal.finished() && aGrabber.readBytes( aBuffer, nBlockSize ) && ind * nBlockSize < nCompressedSize;
+          ind++ )
+    {
+        Sequence < sal_Int8 > aData( nBlockSize );
+        sal_Int32 nLastInflated = 0;
+        sal_Int64 nInBlock = 0;
+
+        aInflaterLocal.setInput( aBuffer );
+        do
+        {
+            nLastInflated = aInflaterLocal.doInflateSegment( aData, 0, nBlockSize );
+            aCRC.updateSegment( aData, nLastInflated );
+            nInBlock += nLastInflated;
+        } while( !aInflater.finished() && nLastInflated );
+
+        nRealSize += nInBlock;
+    }
+
+    *nSize = nRealSize;
+    *nCRC = aCRC.getValue();
+}
+
+/* vim:set shiftwidth=4 softtabstop=4 expandtab: */