Beispiel #1
0
        void ExtractEntry(ZipEntry 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="ZipEntry">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="ZipException">
        /// Password is not set, password is invalid, compression method is invalid,
        /// version required to extract is not supported
        /// </exception>
        public ZipEntry GetNextEntry()
        {
            if (crc == null)
            {
                throw new InvalidOperationException("Closed.");
            }

            if (entry != null)
            {
                CloseEntry();
            }

            int header = inputBuffer.ReadLeInt();

            if (header == ZipConstants.CentralHeaderSignature ||
                header == ZipConstants.EndOfCentralDirectorySignature ||
                header == ZipConstants.CentralHeaderDigitalSignature ||
                header == ZipConstants.ArchiveExtraDataSignature ||
                header == ZipConstants.Zip64CentralFileHeaderSignature)
            {
                // 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 == ZipConstants.SpanningTempSignature) || (header == ZipConstants.SpanningSignature))
            {
                header = inputBuffer.ReadLeInt();
            }

            if (header != ZipConstants.LocalHeaderSignature)
            {
                throw new ZipException("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 = ZipConstants.ConvertToStringExt(flags, buffer);

            entry = new ZipEntry(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, WinZip 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 Zip64 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 - ZipConstants.CryptoHeaderSize != size)))
            {
                throw new ZipException("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;
        }
        /// <summary>
        /// Advances to the next entry in the archive
        /// </summary>
        /// <returns>
        /// The next <see cref="ZipEntry">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="ZipException">
        /// Password is not set, password is invalid, compression method is invalid,
        /// version required to extract is not supported
        /// </exception>
        public ZipEntry GetNextEntry()
        {
            if (crc == null)
            {
                throw new InvalidOperationException("Closed.");
            }

            if (entry != null)
            {
                CloseEntry();
            }

            int header = inputBuffer.ReadLeInt();

            if (header == ZipConstants.CentralHeaderSignature ||
                header == ZipConstants.EndOfCentralDirectorySignature ||
                header == ZipConstants.CentralHeaderDigitalSignature ||
                header == ZipConstants.ArchiveExtraDataSignature ||
                header == ZipConstants.Zip64CentralFileHeaderSignature)
            {
                // 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 == ZipConstants.SpanningTempSignature) || (header == ZipConstants.SpanningSignature))
            {
                header = inputBuffer.ReadLeInt();
            }

            if (header != ZipConstants.LocalHeaderSignature)
            {
                throw new ZipException("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 = ZipConstants.ConvertToStringExt(flags, buffer);

            entry       = new ZipEntry(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, WinZip 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 Zip64 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 - ZipConstants.CryptoHeaderSize != size)))
            {
                throw new ZipException("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);
        }
Beispiel #4
0
        /// <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(ZipEntry 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() != ZipConstants.LocalHeaderSignature)
                {
                    throw new ZipException(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);

                ZipExtraData localExtraData = new ZipExtraData(extraData);

                // Extra data / zip64 checks
                if (localExtraData.Find(1))
                {
                    // 2010-03-04 Forum 10512: removed checks for version >= ZipConstants.VersionZip64
                    // and size or compressedSize = MaxValue, due to rogue creators.

                    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 ZipException("Size invalid for descriptor");
                        }

                        if ((compressedSize != -1) && (compressedSize != entry.CompressedSize))
                        {
                            throw new ZipException("Compressed size invalid for descriptor");
                        }
                    }
                }
                else
                {
                    // No zip64 extra data but entry requires it.
                    if ((extractVersion >= ZipConstants.VersionZip64) &&
                        (((uint)size == uint.MaxValue) || ((uint)compressedSize == uint.MaxValue)))
                    {
                        throw new ZipException("Required Zip64 extended information missing");
                    }
                }

                if (testData)
                {
                    if (entry.IsFile)
                    {
                        if (!entry.IsCompressionMethodSupported())
                        {
                            throw new ZipException("Compression method not supported");
                        }

                        if ((extractVersion > ZipConstants.VersionMadeBy)
                            || ((extractVersion > 20) && (extractVersion < ZipConstants.VersionZip64)))
                        {
                            throw new ZipException(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 ZipException("The library does not support the zip version required to extract this entry");
                        }
                    }
                }

                if (testHeader)
                {
                    if ((extractVersion <= 63) &&	// Ignore later versions as we dont know about them..
                        (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 ZipException(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 ZipException("Reserved bit flags cannot be set.");
                    }

                    // Encryption requires extract version >= 20
                    if (((localFlags & (int)GeneralBitFlags.Encrypted) != 0) && (extractVersion < 20))
                    {
                        throw new ZipException(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 ZipException("Strong encryption flag set but encryption flag is not set");
                        }

                        if (extractVersion < 50)
                        {
                            throw new ZipException(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 ZipException(string.Format("Patched data requires higher version than ({0})", extractVersion));
                    }

                    // Central header flags match local entry flags.
                    if (localFlags != entry.Flags)
                    {
                        throw new ZipException("Central header/local header flags mismatch");
                    }

                    // Central header compression method matches local entry
                    if (entry.CompressionMethod != (CompressionMethod)compressionMethod)
                    {
                        throw new ZipException("Central header/local header compression method mismatch");
                    }

                    if (entry.Version != extractVersion)
                    {
                        throw new ZipException("Extract version mismatch");
                    }

                    // Strong encryption and extract version match
                    if ((localFlags & (int)GeneralBitFlags.StrongEncryption) != 0)
                    {
                        if (extractVersion < 62)
                        {
                            throw new ZipException("Strong encryption flag set but version not high enough");
                        }
                    }

                    if ((localFlags & (int)GeneralBitFlags.HeaderMasked) != 0)
                    {
                        if ((fileTime != 0) || (fileDate != 0))
                        {
                            throw new ZipException("Header masked set but date/time values non-zero");
                        }
                    }

                    if ((localFlags & (int)GeneralBitFlags.Descriptor) == 0)
                    {
                        if (crcValue != (uint)entry.Crc)
                        {
                            throw new ZipException("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 ZipException("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 ZipEntry probably
                    if (entry.Name.Length > storedNameLength)
                    {
                        throw new ZipException("File name length mismatch");
                    }

                    // Name data has already been read convert it and compare.
                    string localName = ZipConstants.ConvertToStringExt(localFlags, nameData);

                    // Central directory and local entry name match
                    if (localName != entry.Name)
                    {
                        throw new ZipException("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 ZipException("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 > ZipConstants.CryptoHeaderSize + 2)
                            {
                                throw new ZipException("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 ZipException("Directory compressed size invalid");
                        }
                    }

                    if (!ZipNameTransform.IsValidName(localName, true))
                    {
                        throw new ZipException("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 ZipException(
                            string.Format("Size mismatch between central header({0}) and local header({1})",
                                entry.Size, size));
                    }

                    if (compressedSize != entry.CompressedSize &&
                        compressedSize != 0xFFFFFFFF && compressedSize != -1)
                    {
                        throw new ZipException(
                            string.Format("Compressed size mismatch between central header({0}) and local header({1})",
                            entry.CompressedSize, compressedSize));
                    }
                }

                int extraLength = storedNameLength + extraDataLength;
                return offsetOfFirstEntry + entry.Offset + ZipConstants.LocalHeaderBaseSize + extraLength;
            }
        }
Beispiel #5
0
        void ExtractEntry(ZipEntry 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);
            }
        }