Example #1
0
        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) {
                Close();
                return null;
            }

            if ( (header == ZipConstants.SpanningTempSignature) || (header == ZipConstants.SpanningSignature) ) {
                header = inputBuffer.ReadLeInt();
            }

            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 {

                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 (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 (entry.IsCompressionMethodSupported()) {
                internalReader = new ReadDataHandler(InitialRead);
            } else {
                internalReader = new ReadDataHandler(ReadingNotSupported);
            }

            return entry;
        }
Example #2
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) {
                }

                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)) {
                        }

                        if ((compressedSize != -1) && (compressedSize != entry.CompressedSize)) {
                        }
                    }
                }
                else
                {
                    // No zip64 extra data but entry requires it.
                    if ((extractVersion >= ZipConstants.VersionZip64) &&
                        (((uint)size == uint.MaxValue) || ((uint)compressedSize == uint.MaxValue)))
                    {
                    }
                }

                if ( testData ) {
                    if ( entry.IsFile ) {
                        if ( !entry.IsCompressionMethodSupported() ) {
                        }

                        if ( (extractVersion > ZipConstants.VersionMadeBy)
                            || ((extractVersion > 20) && (extractVersion < ZipConstants.VersionZip64)) ) {
                        }

                        if ( (localFlags & ( int )(GeneralBitFlags.Patched | GeneralBitFlags.StrongEncryption | GeneralBitFlags.EnhancedCompress | GeneralBitFlags.HeaderMasked)) != 0 ) {

                        }
                    }
                }

                if (testHeader)
                {

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

                    // Directories have zero actual size but can have compressed size
                    if (entry.IsDirectory)
                    {
                        // 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)
                        {

                        }
                        else if (compressedSize > 2)
                        {
                        }
                    }
                }

                // 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.

                int extraLength = storedNameLength + extraDataLength;
                return offsetOfFirstEntry + entry.Offset + ZipConstants.LocalHeaderBaseSize + extraLength;
            }
        }