private Stream ReadData(Stream input)
{
input.Position = DataOffset;
int dataSize = (int)CompressedSize;
Stream stream = new Decrypt1Stream(input, (int)Version, dataSize, DataHash, hashLow: (uint)(Hash & 0xFFFFFFFF), streamMode: StreamMode.Read);
if (Encryption == Cryptography.Magic1 || Encryption == Cryptography.Magic2)
{
int headerSize = Cryptography.GetHeaderSize(Encryption);
stream.Read(new byte[headerSize], 0, headerSize);
dataSize -= headerSize;
stream = new Decrypt2Stream(stream, dataSize, Key, StreamMode.Read);
}
if (Compressed)
{
stream = Compression.UncompressStream(stream);
}
return(stream);
}
public void Write(Stream output, IDirectory inputDirectory)
{
using (Stream inputStream = inputDirectory.ReadFileStream(Hashing.NormalizeFilePath(FilePath)))
using (Md5Stream md5OutputStream = new Md5Stream(output))
{
long headerPosition = output.Position;
const int entryHeaderSize = 32;
long dataStartPosition = headerPosition + entryHeaderSize;
output.Position = dataStartPosition;
uint uncompressedSize = (uint)inputStream.Length;
Stream outputDataStream = md5OutputStream;
Stream outputDataStreamCompressed = null;
if (Compressed)
{
outputDataStreamCompressed = Compression.CompressStream(outputDataStream);
outputDataStream = outputDataStreamCompressed;
}
if (Encryption != 0)
{
int encryptionHeaderSize = Cryptography.GetHeaderSize(Encryption);
if (encryptionHeaderSize >= 8)
{
byte[] header = new byte[encryptionHeaderSize];
Buffer.BlockCopy(BitConverter.GetBytes(Encryption), 0, header, 0, sizeof(uint));
Buffer.BlockCopy(BitConverter.GetBytes(Key), 0, header, 4, sizeof(uint));
if (encryptionHeaderSize == 16)
{
Buffer.BlockCopy(BitConverter.GetBytes(uncompressedSize), 0, header, 8, sizeof(uint));
Buffer.BlockCopy(BitConverter.GetBytes(uncompressedSize), 0, header, 12, sizeof(uint));
}
using (var headerStream = new MemoryStream(header))
{
headerStream.CopyTo(outputDataStream);
}
}
outputDataStream = new Decrypt2Stream(outputDataStream, (int)uncompressedSize, Key, StreamMode.Write);
}
inputStream.CopyTo(outputDataStream);
outputDataStreamCompressed?.Close();
// TODO: HACK to support repacked files
if (DataHash == null)
{
md5OutputStream.Flush();
DataHash = md5OutputStream.Hash;
}
long dataEndPosition = output.Position;
uint compressedSize = (uint)(dataEndPosition - dataStartPosition);
uncompressedSize = Compressed ? uncompressedSize : compressedSize;
using (var decrypt1Stream = new Decrypt1Stream(output, (int)Version, (int)compressedSize, DataHash, hashLow: (uint)(Hash & 0xFFFFFFFF), streamMode: StreamMode.Write))
{
CopyTo(output, decrypt1Stream, dataStartPosition, dataEndPosition);
}
output.Position = headerPosition;
const ulong xorMask1Long = 0x4144104341441043;
const uint xorMask1 = 0x41441043;
const uint xorMask2 = 0x11C22050;
const uint xorMask3 = 0xD05608C3;
const uint xorMask4 = 0x532C7319;
BinaryWriter writer = new BinaryWriter(output, Encoding.ASCII, true);
writer.Write(Hash ^ xorMask1Long);
writer.Write((Version != 2 ? uncompressedSize : compressedSize) ^ xorMask2);
writer.Write((Version != 2 ? compressedSize : uncompressedSize) ^ xorMask3);
writer.Write(BitConverter.ToUInt32(DataHash, 0) ^ xorMask4);
writer.Write(BitConverter.ToUInt32(DataHash, 4) ^ xorMask1);
writer.Write(BitConverter.ToUInt32(DataHash, 8) ^ xorMask1);
writer.Write(BitConverter.ToUInt32(DataHash, 12) ^ xorMask2);
output.Position = dataEndPosition;
}
}