示例#1
0
        /// <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);

            } 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 ReaderDelegate(InitialRead);
            } else {
                internalReader = new ReaderDelegate(ReadingNotSupported);
            }

            return entry;
        }
示例#2
0
        /// <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);
            }
            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 ReaderDelegate(InitialRead);
            }
            else
            {
                internalReader = new ReaderDelegate(ReadingNotSupported);
            }

            return(entry);
        }
示例#3
0
        /// <summary>
        /// Search for and read the central directory of a zip file filling the entries array.
        /// </summary>
        /// <exception cref="System.IO.IOException">
        /// An i/o error occurs.
        /// </exception>
        /// <exception cref="ICSharpCode.SharpZipLib.Zip.ZipException">
        /// The central directory is malformed or cannot be found
        /// </exception>
        void ReadEntries()
        {
            // Search for the End Of Central Directory.  When a zip comment is
            // present the directory will start earlier
            //
            // The search is limited to 64K which is the maximum size of a trailing comment field to aid speed.
            // This should be compatible with both SFX and ZIP files but has only been tested for Zip files
            // If a SFX file has the Zip data attached as a resource and there are other resources occuring later then
            // this could be invalid.
            // Could also speed this up by reading memory in larger blocks.

            if (baseStream_.CanSeek == false) {
                throw new ZipException("ZipFile stream must be seekable");
            }

            long locatedEndOfCentralDir = LocateBlockWithSignature(ZipConstants.EndOfCentralDirectorySignature,
                baseStream_.Length, ZipConstants.EndOfCentralRecordBaseSize, 0xffff);

            if (locatedEndOfCentralDir < 0) {
                throw new ZipException("Cannot find central directory");
            }

            // Read end of central directory record
            ushort thisDiskNumber           = ReadLEUshort();
            ushort startCentralDirDisk      = ReadLEUshort();
            ulong entriesForThisDisk        = ReadLEUshort();
            ulong entriesForWholeCentralDir = ReadLEUshort();
            ulong centralDirSize            = ReadLEUint();
            long offsetOfCentralDir         = ReadLEUint();
            uint commentSize                = ReadLEUshort();

            if ( commentSize > 0 ) {
                byte[] comment = new byte[commentSize];

                StreamUtils.ReadFully(baseStream_, comment);
                comment_ = ZipConstants.ConvertToString(comment);
            }
            else {
                comment_ = string.Empty;
            }

            bool isZip64 = false;

            // Check if zip64 header information is required.
            if ( (thisDiskNumber == 0xffff) ||
                (startCentralDirDisk == 0xffff) ||
                (entriesForThisDisk == 0xffff) ||
                (entriesForWholeCentralDir == 0xffff) ||
                (centralDirSize == 0xffffffff) ||
                (offsetOfCentralDir == 0xffffffff) ) {
                isZip64 = true;

                long offset = LocateBlockWithSignature(ZipConstants.Zip64CentralDirLocatorSignature, locatedEndOfCentralDir, 0, 0x1000);
                if ( offset < 0 ) {
                    throw new ZipException("Cannot find Zip64 locator");
                }

                // number of the disk with the start of the zip64 end of central directory 4 bytes
                // relative offset of the zip64 end of central directory record 8 bytes
                // total number of disks 4 bytes
                ReadLEUint(); // startDisk64 is not currently used
                ulong offset64 = ReadLEUlong();
                uint totalDisks = ReadLEUint();

                baseStream_.Position = (long)offset64;
                long sig64 = ReadLEUint();

                if ( sig64 != ZipConstants.Zip64CentralFileHeaderSignature ) {
                    throw new ZipException(string.Format("Invalid Zip64 Central directory signature at {0:X}", offset64));
                }

                // NOTE: Record size = SizeOfFixedFields + SizeOfVariableData - 12.
                ulong recordSize = ( ulong )ReadLEUlong();
                int versionMadeBy = ReadLEUshort();
                int versionToExtract = ReadLEUshort();
                uint thisDisk = ReadLEUint();
                uint centralDirDisk = ReadLEUint();
                entriesForThisDisk = ReadLEUlong();
                entriesForWholeCentralDir = ReadLEUlong();
                centralDirSize = ReadLEUlong();
                offsetOfCentralDir = (long)ReadLEUlong();

                // NOTE: zip64 extensible data sector (variable size) is ignored.
            }

            entries_ = new ZipEntry[entriesForThisDisk];

            // SFX/embedded support, find the offset of the first entry vis the start of the stream
            // This applies to Zip files that are appended to the end of an SFX stub.
            // Or are appended as a resource to an executable.
            // Zip files created by some archivers have the offsets altered to reflect the true offsets
            // and so dont require any adjustment here...
            // TODO: Difficulty with Zip64 and SFX offset handling needs resolution - maths?
            if ( !isZip64 && (offsetOfCentralDir < locatedEndOfCentralDir - (4 + (long)centralDirSize)) ) {
                offsetOfFirstEntry = locatedEndOfCentralDir - (4 + (long)centralDirSize + offsetOfCentralDir);
                if (offsetOfFirstEntry <= 0) {
                    throw new ZipException("Invalid embedded zip archive");
                }
            }

            baseStream_.Seek(offsetOfFirstEntry + offsetOfCentralDir, SeekOrigin.Begin);

            for (ulong i = 0; i < entriesForThisDisk; i++) {
                if (ReadLEUint() != ZipConstants.CentralHeaderSignature) {
                    throw new ZipException("Wrong Central Directory signature");
                }

                int versionMadeBy      = ReadLEUshort();
                int versionToExtract   = ReadLEUshort();
                int bitFlags           = ReadLEUshort();
                int method             = ReadLEUshort();
                uint dostime           = ReadLEUint();
                uint crc               = ReadLEUint();
                long csize             = (long)ReadLEUint();
                long size              = (long)ReadLEUint();
                int nameLen            = ReadLEUshort();
                int extraLen           = ReadLEUshort();
                int commentLen         = ReadLEUshort();

                int diskStartNo        = ReadLEUshort();  // Not currently used
                int internalAttributes = ReadLEUshort();  // Not currently used

                uint externalAttributes = ReadLEUint();
                long offset             = ReadLEUint();

                byte[] buffer = new byte[Math.Max(nameLen, commentLen)];

                StreamUtils.ReadFully(baseStream_, buffer, 0, nameLen);
                string name = ZipConstants.ConvertToStringExt(bitFlags, buffer, nameLen);

                // eliminate system id from version (use version only)
                versionToExtract &= 0x00FF;
                versionMadeBy &= 0x00FF;

                ZipEntry entry = new ZipEntry(name, versionToExtract, versionMadeBy, (CompressionMethod)method);
                entry.Crc = crc & 0xffffffffL;
                entry.Size = size & 0xffffffffL;
                entry.CompressedSize = csize & 0xffffffffL;
                entry.Flags = bitFlags;
                entry.DosTime = (uint)dostime;

                if ((bitFlags & 8) == 0) {
                    entry.CryptoCheckValue = (byte)(crc >> 24);
                }
                else {
                    entry.CryptoCheckValue = (byte)((dostime >> 8) & 0xff);
                }

                if (extraLen > 0) {
                    byte[] extra = new byte[extraLen];
                    StreamUtils.ReadFully(baseStream_, extra);
                    entry.ExtraData = extra;
                }

                entry.ProcessExtraData(false);

                if (commentLen > 0) {
                    StreamUtils.ReadFully(baseStream_, buffer, 0, commentLen);
                    entry.Comment = ZipConstants.ConvertToStringExt(bitFlags, buffer, commentLen);
                }

                entry.ZipFileIndex           = (long)i;
                entry.Offset                 = offset;
                entry.ExternalFileAttributes = (int)externalAttributes;

                entries_[i] = entry;
            }
        }
示例#4
0
        public ZipEntry GetNextEntry()
        {
            if (_crc == null)
            {
                throw new InvalidOperationException("Closed.");
            }
            if (_entry != null)
            {
                CloseEntry();
            }
            var num = InputBuffer.ReadLeInt();
            switch (num)
            {
                case ZipConstants.CentralHeaderSignature:
                case ZipConstants.EndOfCentralDirectorySignature:
                case ZipConstants.CentralHeaderDigitalSignature:
                case ZipConstants.ArchiveExtraDataSignature:
                case 0x6064b50:
                    Close();
                    return null;

                case 0x30304b50:
                case ZipConstants.SpanningSignature:
                    num = InputBuffer.ReadLeInt();
                    break;
            }
            if (num != ZipConstants.LocalHeaderSignature)
            {
                throw new ZipException("Wrong Local header signature: 0x" + $"{num:X}");
            }
            var versionRequiredToExtract = (short)InputBuffer.ReadLeShort();
            _flags = InputBuffer.ReadLeShort();
            _method = InputBuffer.ReadLeShort();
            var num3 = (uint)InputBuffer.ReadLeInt();
            var num4 = InputBuffer.ReadLeInt();
            Csize = InputBuffer.ReadLeInt();
            _size = InputBuffer.ReadLeInt();
            var num5 = InputBuffer.ReadLeShort();
            var num6 = InputBuffer.ReadLeShort();
            var flag = (_flags & 1) == 1;
            var buffer = new byte[num5];
            InputBuffer.ReadRawBuffer(buffer);
            var name = ZipConstants.ConvertToStringExt(_flags, buffer);
            _entry = new ZipEntry(name, versionRequiredToExtract)
            {
                Flags = _flags,
                CompressionMethod = (CompressionMethod) _method
            };
            if ((_flags & 8) == 0)
            {
                _entry.Crc = num4 & 0xffffffffL;
                _entry.Size = _size & 0xffffffffL;
                _entry.CompressedSize = Csize & 0xffffffffL;
                _entry.CryptoCheckValue = (byte)((num4 >> 0x18) & 0xff);
            }
            else
            {
                if (num4 != 0)
                {
                    _entry.Crc = num4 & 0xffffffffL;
                }
                if (_size != 0L)
                {
                    _entry.Size = _size & 0xffffffffL;
                }
                if (Csize != 0L)
                {
                    _entry.CompressedSize = Csize & 0xffffffffL;
                }
                _entry.CryptoCheckValue = (byte)((num3 >> 8) & 0xff);
            }
            _entry.DosTime = num3;
            if (num6 > 0)
            {
                var buffer2 = new byte[num6];
                InputBuffer.ReadRawBuffer(buffer2);
                _entry.ExtraData = buffer2;
            }
            _entry.ProcessExtraData(true);
            if (_entry.CompressedSize >= 0L)
            {
                Csize = _entry.CompressedSize;
            }
            if (_entry.Size >= 0L)
            {
                _size = _entry.Size;
            }
            if ((_method == 0) && ((!flag && (Csize != _size)) || (flag && ((Csize - 12L) != _size))))
            {
                throw new ZipException("Stored, but compressed != uncompressed");
            }
            if (_entry.IsCompressionMethodSupported())
            {
                _internalReader = InitialRead;
            }
            else
            {
                _internalReader = ReadingNotSupported;
            }
            return _entry;
        }
示例#5
0
        public ZipEntry GetNextEntry()
        {
            if (_crc == null)
            {
                throw new InvalidOperationException("Closed.");
            }
            if (_entry != null)
            {
                CloseEntry();
            }
            var num = InputBuffer.ReadLeInt();

            switch (num)
            {
            case ZipConstants.CentralHeaderSignature:
            case ZipConstants.EndOfCentralDirectorySignature:
            case ZipConstants.CentralHeaderDigitalSignature:
            case ZipConstants.ArchiveExtraDataSignature:
            case 0x6064b50:
                Close();
                return(null);

            case 0x30304b50:
            case ZipConstants.SpanningSignature:
                num = InputBuffer.ReadLeInt();
                break;
            }
            if (num != ZipConstants.LocalHeaderSignature)
            {
                throw new ZipException("Wrong Local header signature: 0x" + $"{num:X}");
            }
            var versionRequiredToExtract = (short)InputBuffer.ReadLeShort();

            _flags  = InputBuffer.ReadLeShort();
            _method = InputBuffer.ReadLeShort();
            var num3 = (uint)InputBuffer.ReadLeInt();
            var num4 = InputBuffer.ReadLeInt();

            Csize = InputBuffer.ReadLeInt();
            _size = InputBuffer.ReadLeInt();
            var num5   = InputBuffer.ReadLeShort();
            var num6   = InputBuffer.ReadLeShort();
            var flag   = (_flags & 1) == 1;
            var buffer = new byte[num5];

            InputBuffer.ReadRawBuffer(buffer);
            var name = ZipConstants.ConvertToStringExt(_flags, buffer);

            _entry = new ZipEntry(name, versionRequiredToExtract)
            {
                Flags             = _flags,
                CompressionMethod = (CompressionMethod)_method
            };
            if ((_flags & 8) == 0)
            {
                _entry.Crc              = num4 & 0xffffffffL;
                _entry.Size             = _size & 0xffffffffL;
                _entry.CompressedSize   = Csize & 0xffffffffL;
                _entry.CryptoCheckValue = (byte)((num4 >> 0x18) & 0xff);
            }
            else
            {
                if (num4 != 0)
                {
                    _entry.Crc = num4 & 0xffffffffL;
                }
                if (_size != 0L)
                {
                    _entry.Size = _size & 0xffffffffL;
                }
                if (Csize != 0L)
                {
                    _entry.CompressedSize = Csize & 0xffffffffL;
                }
                _entry.CryptoCheckValue = (byte)((num3 >> 8) & 0xff);
            }
            _entry.DosTime = num3;
            if (num6 > 0)
            {
                var buffer2 = new byte[num6];
                InputBuffer.ReadRawBuffer(buffer2);
                _entry.ExtraData = buffer2;
            }
            _entry.ProcessExtraData(true);
            if (_entry.CompressedSize >= 0L)
            {
                Csize = _entry.CompressedSize;
            }
            if (_entry.Size >= 0L)
            {
                _size = _entry.Size;
            }
            if ((_method == 0) && ((!flag && (Csize != _size)) || (flag && ((Csize - 12L) != _size))))
            {
                throw new ZipException("Stored, but compressed != uncompressed");
            }
            if (_entry.IsCompressionMethodSupported())
            {
                _internalReader = InitialRead;
            }
            else
            {
                _internalReader = ReadingNotSupported;
            }
            return(_entry);
        }
示例#6
0
 private void ReadEntries()
 {
     if (!_baseStream.CanSeek)
     {
         throw new ZipException("ZipFile stream must be seekable");
     }
     var endLocation = LocateBlockWithSignature(ZipConstants.EndOfCentralDirectorySignature, _baseStream.Length,
         0x16, 0xffff);
     if (endLocation < 0L)
     {
         throw new ZipException("Cannot find central directory");
     }
     var num2 = ReadLeUshort();
     var num3 = ReadLeUshort();
     ulong num4 = ReadLeUshort();
     ulong num5 = ReadLeUshort();
     ulong num6 = ReadLeUint();
     long num7 = ReadLeUint();
     uint num8 = ReadLeUshort();
     if (num8 > 0)
     {
         var buffer = new byte[num8];
         StreamUtils.ReadFully(_baseStream, buffer);
         _comment = ZipConstants.ConvertToString(buffer);
     }
     else
     {
         _comment = string.Empty;
     }
     var flag = false;
     if ((((num2 == 0xffff) || (num3 == 0xffff)) || ((num4 == 0xffffL) 
         || (num5 == 0xffffL))) || ((num6 == 0xffffffffL) || (num7 == 0xffffffffL)))
     {
         flag = true;
         if (LocateBlockWithSignature(ZipConstants.ArchiveExtraDataSignature, endLocation, 0, DefaultBufferSize) < 0L)
         {
             throw new ZipException("Cannot find Zip64 locator");
         }
         ReadLeUint();
         var num10 = ReadLeUlong();
         ReadLeUint();
         _baseStream.Position = (long)num10;
         long num11 = ReadLeUint();
         if (num11 != 0x6064b50L)
         {
             throw new ZipException($"Invalid Zip64 Central directory signature at {num10:X}");
         }
         ReadLeUlong();
         ReadLeUshort();
         ReadLeUshort();
         ReadLeUint();
         ReadLeUint();
         num4 = ReadLeUlong();
         num5 = ReadLeUlong();
         num6 = ReadLeUlong();
         num7 = (long)ReadLeUlong();
     }
     _entries = new ZipEntry[num4];
     if (!flag && (num7 < (long)(((ulong)endLocation) - (4L + num6))))
     {
         _offsetOfFirstEntry = endLocation - ((4L + ((long)num6)) + num7);
         if (_offsetOfFirstEntry <= 0L)
         {
             throw new ZipException("Invalid embedded zip archive");
         }
     }
     _baseStream.Seek(_offsetOfFirstEntry + num7, SeekOrigin.Begin);
     for (ulong i = 0L; i < num4; i += (ulong)1L)
     {
         if (ReadLeUint() != ZipConstants.CentralHeaderSignature)
         {
             throw new ZipException("Wrong Central Directory signature");
         }
         int madeByInfo = ReadLeUshort();
         int versionRequiredToExtract = ReadLeUshort();
         int flags = ReadLeUshort();
         int num16 = ReadLeUshort();
         var num17 = ReadLeUint();
         var num18 = ReadLeUint();
         long num19 = ReadLeUint();
         long num20 = ReadLeUint();
         int num21 = ReadLeUshort();
         int num22 = ReadLeUshort();
         int num23 = ReadLeUshort();
         ReadLeUshort();
         ReadLeUshort();
         var num24 = ReadLeUint();
         long num25 = ReadLeUint();
         var buffer2 = new byte[Math.Max(num21, num23)];
         StreamUtils.ReadFully(_baseStream, buffer2, 0, num21);
         var entry = new ZipEntry(ZipConstants.ConvertToStringExt(flags, buffer2, num21), versionRequiredToExtract, madeByInfo, (CompressionMethod)num16)
         {
             Crc = num18 & 0xffffffffL,
             Size = num20 & 0xffffffffL,
             CompressedSize = num19 & 0xffffffffL,
             Flags = flags,
             DosTime = num17,
             ZipFileIndex = (long)i,
             Offset = num25,
             ExternalFileAttributes = (int)num24
         };
         if ((flags & 8) == 0)
         {
             entry.CryptoCheckValue = (byte)(num18 >> 0x18);
         }
         else
         {
             entry.CryptoCheckValue = (byte)((num17 >> 8) & 0xff);
         }
         if (num22 > 0)
         {
             var buffer3 = new byte[num22];
             StreamUtils.ReadFully(_baseStream, buffer3);
             entry.ExtraData = buffer3;
         }
         entry.ProcessExtraData(false);
         if (num23 > 0)
         {
             StreamUtils.ReadFully(_baseStream, buffer2, 0, num23);
             entry.Comment = ZipConstants.ConvertToStringExt(flags, buffer2, num23);
         }
         _entries[(int)((IntPtr)i)] = entry;
     }
 }