/// <summary>
/// Test a local header against that provided from the central directory
/// </summary>
/// <param name="entry">
/// The entry to test against
/// </param>
/// <param name="tests">The type of <see cref="HeaderTest">tests</see> to carry out.</param>
/// <returns>The offset of the entries data in the file</returns>
long TestLocalHeader( BlubbZipEntry entry, HeaderTest tests ) {
lock( baseStream_ ) {
bool testHeader = ( tests & HeaderTest.Header ) != 0;
bool testData = ( tests & HeaderTest.Extract ) != 0;
baseStream_.Seek( offsetOfFirstEntry + entry.Offset, SeekOrigin.Begin );
if( (int)ReadLEUint() != BlubbZipConstants.LocalHeaderSignature ) {
throw new BlubbZipException( string.Format( "Wrong local header signature @{0:X}", offsetOfFirstEntry + entry.Offset ) );
}
short extractVersion = (short)ReadLEUshort();
short localFlags = (short)ReadLEUshort();
short compressionMethod = (short)ReadLEUshort();
short fileTime = (short)ReadLEUshort();
short fileDate = (short)ReadLEUshort();
uint crcValue = ReadLEUint();
long compressedSize = ReadLEUint();
long size = ReadLEUint();
int storedNameLength = ReadLEUshort();
int extraDataLength = ReadLEUshort();
byte[] nameData = new byte[ storedNameLength ];
StreamUtils.ReadFully( baseStream_, nameData );
byte[] extraData = new byte[ extraDataLength ];
StreamUtils.ReadFully( baseStream_, extraData );
BlubbZipExtraData localExtraData = new BlubbZipExtraData( extraData );
// Extra data / blubb64 checks
if( localExtraData.Find( 1 ) ) {
// TODO Check for tag values being distinct.. Multiple blubb64 tags means what?
// Blubb64 extra data but 'extract version' is too low
if( extractVersion < BlubbZipConstants.VersionBlubb64 ) {
throw new BlubbZipException(
string.Format( "Extra data contains Blubb64 information but version {0}.{1} is not high enough",
extractVersion / 10, extractVersion % 10 ) );
}
// Blubb64 extra data but size fields dont indicate its required.
if( ( (uint)size != uint.MaxValue ) && ( (uint)compressedSize != uint.MaxValue ) ) {
throw new BlubbZipException( "Entry sizes not correct for Blubb64" );
}
size = localExtraData.ReadLong();
compressedSize = localExtraData.ReadLong();
if( ( localFlags & (int)GeneralBitFlags.Descriptor ) != 0 ) {
// These may be valid if patched later
if( ( size != -1 ) && ( size != entry.Size ) ) {
throw new BlubbZipException( "Size invalid for descriptor" );
}
if( ( compressedSize != -1 ) && ( compressedSize != entry.CompressedSize ) ) {
throw new BlubbZipException( "Compressed size invalid for descriptor" );
}
}
} else {
// No blubb64 extra data but entry requires it.
if( ( extractVersion >= BlubbZipConstants.VersionBlubb64 ) &&
( ( (uint)size == uint.MaxValue ) || ( (uint)compressedSize == uint.MaxValue ) ) ) {
throw new BlubbZipException( "Required Blubb64 extended information missing" );
}
}
if( testData ) {
if( entry.IsFile ) {
if( !entry.IsCompressionMethodSupported() ) {
throw new BlubbZipException( "Compression method not supported" );
}
if( ( extractVersion > BlubbZipConstants.VersionMadeBy )
|| ( ( extractVersion > 20 ) && ( extractVersion < BlubbZipConstants.VersionBlubb64 ) ) ) {
throw new BlubbZipException( string.Format( "Version required to extract this entry not supported ({0})", extractVersion ) );
}
if( ( localFlags & (int)( GeneralBitFlags.Patched | GeneralBitFlags.StrongEncryption | GeneralBitFlags.EnhancedCompress | GeneralBitFlags.HeaderMasked ) ) != 0 ) {
throw new BlubbZipException( "The library does not support the blubb version required to extract this entry" );
}
}
}
if( testHeader ) {
if( ( extractVersion <= 63 ) &&
( extractVersion != 10 ) &&
( extractVersion != 11 ) &&
( extractVersion != 20 ) &&
( extractVersion != 21 ) &&
( extractVersion != 25 ) &&
( extractVersion != 27 ) &&
( extractVersion != 45 ) &&
( extractVersion != 46 ) &&
( extractVersion != 50 ) &&
( extractVersion != 51 ) &&
( extractVersion != 52 ) &&
( extractVersion != 61 ) &&
( extractVersion != 62 ) &&
( extractVersion != 63 )
) {
throw new BlubbZipException( string.Format( "Version required to extract this entry is invalid ({0})", extractVersion ) );
}
// Local entry flags dont have reserved bit set on.
if( ( localFlags & (int)( GeneralBitFlags.ReservedPKware4 | GeneralBitFlags.ReservedPkware14 | GeneralBitFlags.ReservedPkware15 ) ) != 0 ) {
throw new BlubbZipException( "Reserved bit flags cannot be set." );
}
// Encryption requires extract version >= 20
if( ( ( localFlags & (int)GeneralBitFlags.Encrypted ) != 0 ) && ( extractVersion < 20 ) ) {
throw new BlubbZipException( string.Format( "Version required to extract this entry is too low for encryption ({0})", extractVersion ) );
}
// Strong encryption requires encryption flag to be set and extract version >= 50.
if( ( localFlags & (int)GeneralBitFlags.StrongEncryption ) != 0 ) {
if( ( localFlags & (int)GeneralBitFlags.Encrypted ) == 0 ) {
throw new BlubbZipException( "Strong encryption flag set but encryption flag is not set" );
}
if( extractVersion < 50 ) {
throw new BlubbZipException( string.Format( "Version required to extract this entry is too low for encryption ({0})", extractVersion ) );
}
}
// Patched entries require extract version >= 27
if( ( ( localFlags & (int)GeneralBitFlags.Patched ) != 0 ) && ( extractVersion < 27 ) ) {
throw new BlubbZipException( string.Format( "Patched data requires higher version than ({0})", extractVersion ) );
}
// Central header flags match local entry flags.
if( localFlags != entry.Flags ) {
throw new BlubbZipException( "Central header/local header flags mismatch" );
}
// Central header compression method matches local entry
if( entry.CompressionMethod != (CompressionMethod)compressionMethod ) {
throw new BlubbZipException( "Central header/local header compression method mismatch" );
}
if( entry.Version != extractVersion ) {
throw new BlubbZipException( "Extract version mismatch" );
}
// Strong encryption and extract version match
if( ( localFlags & (int)GeneralBitFlags.StrongEncryption ) != 0 ) {
if( extractVersion < 62 ) {
throw new BlubbZipException( "Strong encryption flag set but version not high enough" );
}
}
if( ( localFlags & (int)GeneralBitFlags.HeaderMasked ) != 0 ) {
if( ( fileTime != 0 ) || ( fileDate != 0 ) ) {
throw new BlubbZipException( "Header masked set but date/time values non-zero" );
}
}
if( ( localFlags & (int)GeneralBitFlags.Descriptor ) == 0 ) {
if( crcValue != (uint)entry.Crc ) {
throw new BlubbZipException( "Central header/local header crc mismatch" );
}
}
// Crc valid for empty entry.
// This will also apply to streamed entries where size isnt known and the header cant be patched
if( ( size == 0 ) && ( compressedSize == 0 ) ) {
if( crcValue != 0 ) {
throw new BlubbZipException( "Invalid CRC for empty entry" );
}
}
// TODO: make test more correct... can't compare lengths as was done originally as this can fail for MBCS strings
// Assuming a code page at this point is not valid? Best is to store the name length in the BlubbEntry probably
if( entry.Name.Length > storedNameLength ) {
throw new BlubbZipException( "File name length mismatch" );
}
// Name data has already been read convert it and compare.
string localName = BlubbZipConstants.ConvertToStringExt( localFlags, nameData );
// Central directory and local entry name match
if( localName != entry.Name ) {
throw new BlubbZipException( "Central header and local header file name mismatch" );
}
// Directories have zero actual size but can have compressed size
if( entry.IsDirectory ) {
if( size > 0 ) {
throw new BlubbZipException( "Directory cannot have size" );
}
// There may be other cases where the compressed size can be greater than this?
// If so until details are known we will be strict.
if( entry.IsCrypted ) {
if( compressedSize > BlubbZipConstants.CryptoHeaderSize + 2 ) {
throw new BlubbZipException( "Directory compressed size invalid" );
}
} else if( compressedSize > 2 ) {
// When not compressed the directory size can validly be 2 bytes
// if the true size wasnt known when data was originally being written.
// NOTE: Versions of the library 0.85.4 and earlier always added 2 bytes
throw new BlubbZipException( "Directory compressed size invalid" );
}
}
if( !BlubbZipNameTransform.IsValidName( localName, true ) ) {
throw new BlubbZipException( "Name is invalid" );
}
}
// Tests that apply to both data and header.
// Size can be verified only if it is known in the local header.
// it will always be known in the central header.
if( ( ( localFlags & (int)GeneralBitFlags.Descriptor ) == 0 ) ||
( ( size > 0 ) || ( compressedSize > 0 ) ) ) {
if( size != entry.Size ) {
throw new BlubbZipException(
string.Format( "Size mismatch between central header({0}) and local header({1})",
entry.Size, size ) );
}
if( compressedSize != entry.CompressedSize ) {
throw new BlubbZipException(
string.Format( "Compressed size mismatch between central header({0}) and local header({1})",
entry.CompressedSize, compressedSize ) );
}
}
int extraLength = storedNameLength + extraDataLength;
return offsetOfFirstEntry + entry.Offset + BlubbZipConstants.LocalHeaderBaseSize + extraLength;
}
}
/// <summary>
/// Advances to the next entry in the archive
/// </summary>
/// <returns>
/// The next <see cref="BlubbEntry">entry</see> in the archive or null if there are no more entries.
/// </returns>
/// <remarks>
/// If the previous entry is still open <see cref="CloseEntry">CloseEntry</see> is called.
/// </remarks>
/// <exception cref="InvalidOperationException">
/// Input stream is closed
/// </exception>
/// <exception cref="BlubbException">
/// Password is not set, password is invalid, compression method is invalid,
/// version required to extract is not supported
/// </exception>
public BlubbZipEntry GetNextEntry()
{
if (crc == null)
{
throw new InvalidOperationException("Closed.");
}
if (entry != null)
{
CloseEntry();
}
int header = inputBuffer.ReadLeInt();
if (header == BlubbZipConstants.CentralHeaderSignature ||
header == BlubbZipConstants.EndOfCentralDirectorySignature ||
header == BlubbZipConstants.CentralHeaderDigitalSignature ||
header == BlubbZipConstants.ArchiveExtraDataSignature ||
header == BlubbZipConstants.Blubb64CentralFileHeaderSignature)
{
// No more individual entries exist
Close();
return(null);
}
// -jr- 07-Dec-2003 Ignore spanning temporary signatures if found
// Spanning signature is same as descriptor signature and is untested as yet.
if ((header == BlubbZipConstants.SpanningTempSignature) || (header == BlubbZipConstants.SpanningSignature))
{
header = inputBuffer.ReadLeInt();
}
if (header != BlubbZipConstants.LocalHeaderSignature)
{
throw new BlubbZipException("Wrong Local header signature: 0x" + String.Format("{0:X}", header));
}
short versionRequiredToExtract = (short)inputBuffer.ReadLeShort();
flags = inputBuffer.ReadLeShort();
method = inputBuffer.ReadLeShort();
uint dostime = (uint)inputBuffer.ReadLeInt();
int crc2 = inputBuffer.ReadLeInt();
csize = inputBuffer.ReadLeInt();
size = inputBuffer.ReadLeInt();
int nameLen = inputBuffer.ReadLeShort();
int extraLen = inputBuffer.ReadLeShort();
bool isCrypted = (flags & 1) == 1;
byte[] buffer = new byte[nameLen];
inputBuffer.ReadRawBuffer(buffer);
string name = BlubbZipConstants.ConvertToStringExt(flags, buffer);
entry = new BlubbZipEntry(name, versionRequiredToExtract);
entry.Flags = flags;
entry.CompressionMethod = (CompressionMethod)method;
if ((flags & 8) == 0)
{
entry.Crc = crc2 & 0xFFFFFFFFL;
entry.Size = size & 0xFFFFFFFFL;
entry.CompressedSize = csize & 0xFFFFFFFFL;
entry.CryptoCheckValue = (byte)((crc2 >> 24) & 0xff);
}
else
{
// This allows for GNU, WinBlubb and possibly other archives, the PKZIP spec
// says these values are zero under these circumstances.
if (crc2 != 0)
{
entry.Crc = crc2 & 0xFFFFFFFFL;
}
if (size != 0)
{
entry.Size = size & 0xFFFFFFFFL;
}
if (csize != 0)
{
entry.CompressedSize = csize & 0xFFFFFFFFL;
}
entry.CryptoCheckValue = (byte)((dostime >> 8) & 0xff);
}
entry.DosTime = dostime;
// If local header requires Blubb64 is true then the extended header should contain
// both values.
// Handle extra data if present. This can set/alter some fields of the entry.
if (extraLen > 0)
{
byte[] extra = new byte[extraLen];
inputBuffer.ReadRawBuffer(extra);
entry.ExtraData = extra;
}
entry.ProcessExtraData(true);
if (entry.CompressedSize >= 0)
{
csize = entry.CompressedSize;
}
if (entry.Size >= 0)
{
size = entry.Size;
}
if (method == (int)CompressionMethod.Stored && (!isCrypted && csize != size || (isCrypted && csize - BlubbZipConstants.CryptoHeaderSize != size)))
{
throw new BlubbZipException("Stored, but compressed != uncompressed");
}
// Determine how to handle reading of data if this is attempted.
if (entry.IsCompressionMethodSupported())
{
internalReader = new ReadDataHandler(InitialRead);
}
else
{
internalReader = new ReadDataHandler(ReadingNotSupported);
}
return(entry);
}
void ExtractEntry(BlubbZipEntry entry)
{
bool doExtraction = entry.IsCompressionMethodSupported();
string targetName = entry.Name;
if (doExtraction)
{
if (entry.IsFile)
{
targetName = extractNameTransform_.TransformFile(targetName);
}
else if (entry.IsDirectory)
{
targetName = extractNameTransform_.TransformDirectory(targetName);
}
doExtraction = !((targetName == null) || (targetName.Length == 0));
}
// TODO: Fire delegate/throw exception were compression method not supported, or name is invalid?
string dirName = null;
if (doExtraction)
{
if (entry.IsDirectory)
{
dirName = targetName;
}
else
{
dirName = Path.GetDirectoryName(Path.GetFullPath(targetName));
}
}
if (doExtraction && !Directory.Exists(dirName))
{
if (!entry.IsDirectory || CreateEmptyDirectories)
{
try {
Directory.CreateDirectory(dirName);
} catch (Exception ex) {
doExtraction = false;
if (events_ != null)
{
if (entry.IsDirectory)
{
continueRunning_ = events_.OnDirectoryFailure(targetName, ex);
}
else
{
continueRunning_ = events_.OnFileFailure(targetName, ex);
}
}
else
{
continueRunning_ = false;
throw;
}
}
}
}
if (doExtraction && entry.IsFile)
{
ExtractFileEntry(entry, targetName);
}
}
/// <summary>
/// Advances to the next entry in the archive
/// </summary>
/// <returns>
/// The next <see cref="BlubbEntry">entry</see> in the archive or null if there are no more entries.
/// </returns>
/// <remarks>
/// If the previous entry is still open <see cref="CloseEntry">CloseEntry</see> is called.
/// </remarks>
/// <exception cref="InvalidOperationException">
/// Input stream is closed
/// </exception>
/// <exception cref="BlubbException">
/// Password is not set, password is invalid, compression method is invalid,
/// version required to extract is not supported
/// </exception>
public BlubbZipEntry GetNextEntry() {
if( crc == null ) {
throw new InvalidOperationException( "Closed." );
}
if( entry != null ) {
CloseEntry();
}
int header = inputBuffer.ReadLeInt();
if( header == BlubbZipConstants.CentralHeaderSignature ||
header == BlubbZipConstants.EndOfCentralDirectorySignature ||
header == BlubbZipConstants.CentralHeaderDigitalSignature ||
header == BlubbZipConstants.ArchiveExtraDataSignature ||
header == BlubbZipConstants.Blubb64CentralFileHeaderSignature ) {
// No more individual entries exist
Close();
return null;
}
// -jr- 07-Dec-2003 Ignore spanning temporary signatures if found
// Spanning signature is same as descriptor signature and is untested as yet.
if( ( header == BlubbZipConstants.SpanningTempSignature ) || ( header == BlubbZipConstants.SpanningSignature ) ) {
header = inputBuffer.ReadLeInt();
}
if( header != BlubbZipConstants.LocalHeaderSignature ) {
throw new BlubbZipException( "Wrong Local header signature: 0x" + String.Format( "{0:X}", header ) );
}
short versionRequiredToExtract = (short)inputBuffer.ReadLeShort();
flags = inputBuffer.ReadLeShort();
method = inputBuffer.ReadLeShort();
uint dostime = (uint)inputBuffer.ReadLeInt();
int crc2 = inputBuffer.ReadLeInt();
csize = inputBuffer.ReadLeInt();
size = inputBuffer.ReadLeInt();
int nameLen = inputBuffer.ReadLeShort();
int extraLen = inputBuffer.ReadLeShort();
bool isCrypted = ( flags & 1 ) == 1;
byte[] buffer = new byte[ nameLen ];
inputBuffer.ReadRawBuffer( buffer );
string name = BlubbZipConstants.ConvertToStringExt( flags, buffer );
entry = new BlubbZipEntry( name, versionRequiredToExtract );
entry.Flags = flags;
entry.CompressionMethod = (CompressionMethod)method;
if( ( flags & 8 ) == 0 ) {
entry.Crc = crc2 & 0xFFFFFFFFL;
entry.Size = size & 0xFFFFFFFFL;
entry.CompressedSize = csize & 0xFFFFFFFFL;
entry.CryptoCheckValue = (byte)( ( crc2 >> 24 ) & 0xff );
} else {
// This allows for GNU, WinBlubb and possibly other archives, the PKZIP spec
// says these values are zero under these circumstances.
if( crc2 != 0 ) {
entry.Crc = crc2 & 0xFFFFFFFFL;
}
if( size != 0 ) {
entry.Size = size & 0xFFFFFFFFL;
}
if( csize != 0 ) {
entry.CompressedSize = csize & 0xFFFFFFFFL;
}
entry.CryptoCheckValue = (byte)( ( dostime >> 8 ) & 0xff );
}
entry.DosTime = dostime;
// If local header requires Blubb64 is true then the extended header should contain
// both values.
// Handle extra data if present. This can set/alter some fields of the entry.
if( extraLen > 0 ) {
byte[] extra = new byte[ extraLen ];
inputBuffer.ReadRawBuffer( extra );
entry.ExtraData = extra;
}
entry.ProcessExtraData( true );
if( entry.CompressedSize >= 0 ) {
csize = entry.CompressedSize;
}
if( entry.Size >= 0 ) {
size = entry.Size;
}
if( method == (int)CompressionMethod.Stored && ( !isCrypted && csize != size || ( isCrypted && csize - BlubbZipConstants.CryptoHeaderSize != size ) ) ) {
throw new BlubbZipException( "Stored, but compressed != uncompressed" );
}
// Determine how to handle reading of data if this is attempted.
if( entry.IsCompressionMethodSupported() ) {
internalReader = new ReadDataHandler( InitialRead );
} else {
internalReader = new ReadDataHandler( ReadingNotSupported );
}
return entry;
}
