public static void Unpack(string inputFileName, string outputDirectory, byte[] key, byte[] iv)
{
var info = new List <string>();
if (key.Length != 16)
{
throw new ApplicationException("Invalid key length");
}
if (iv.Length != 16)
{
throw new ApplicationException("Invalid IV length");
}
if (!File.Exists(inputFileName))
{
throw new ApplicationException("Input file not found");
}
info.Add("name " + Path.GetFileName(inputFileName));
info.Add("key " + BitConverter.ToString(key).Replace("-", ""));
info.Add("iv " + BitConverter.ToString(iv).Replace("-", ""));
// decrypt
var decryptedData = new MemoryStream();
var aes = new RijndaelManaged
{
Mode = CipherMode.CFB,
Key = key,
IV = iv,
Padding = PaddingMode.None
};
var decryptor = new NoPaddingTransformWrapper(aes.CreateDecryptor());
using (var inputFile = File.OpenRead(inputFileName))
{
info.Add("original.size " + inputFile.Length);
info.Add("original.sha256 " + HashStream(inputFile));
using (var cryptoStream = new CryptoStream(inputFile, decryptor, CryptoStreamMode.Read))
{
cryptoStream.CopyTo(decryptedData);
}
info.Add("decrypted.size " + decryptedData.Length);
info.Add("decrypted.sha256 " + HashStream(decryptedData));
}
var outputDecryptedName = Path.Combine(outputDirectory, Path.GetFileNameWithoutExtension(inputFileName)) + ".decrypted";
File.WriteAllBytes(outputDecryptedName, decryptedData.ToArray());
// First 4 bytes are unknown. The next 2 bytes are the zlib header 789C. After that the raw deflate data follows.
var header = new byte[6];
if (decryptedData.Read(header, 0, header.Length) != header.Length)
{
throw new IOException("Did not read the full header");
}
if (header[4] != 0x78 || header[5] != 0x9C)//zlib header
{
throw new ApplicationException("Incorrect key/iv");
}
decryptedData.Position = 6;
int revision;
// decompress using deflate
var tempFileName = Path.Combine(outputDirectory, "TempDataCenter");
using (var unpackedData = File.Create(tempFileName))
{
using (var deflateStream = new DeflateStream(decryptedData, CompressionMode.Decompress, true))
{
deflateStream.CopyTo(unpackedData);
}
info.Add("unpacked.size " + unpackedData.Length);
info.Add("unpacked.sha256 " + HashStream(unpackedData));
using (var reader = new BinaryReader(unpackedData, Encoding.Unicode, true))
{
unpackedData.Position = 0x0C;
revision = reader.ReadInt32();
info.Insert(1, "revision " + revision);
}
}
File.WriteAllLines(Path.ChangeExtension(outputDecryptedName, revision + ".dcinfo"), info);
File.Copy(tempFileName, Path.ChangeExtension(outputDecryptedName, revision + ".unpacked"), true);
File.Delete(tempFileName);
File.Delete(outputDecryptedName);
}
public static void Unpack(string inputFileName, string outputBase, byte[] key, byte[] iv)
{
var info = new List<string>();
if (key.Length != 16)
throw new ApplicationException("Invalid key length");
if (iv.Length != 16)
throw new ApplicationException("Invalid IV length");
if (!File.Exists(inputFileName))
throw new ApplicationException("Input file not found");
info.Add("name " + Path.GetFileName(inputFileName));
info.Add("key " + BitConverter.ToString(key).Replace("-", ""));
info.Add("iv " + BitConverter.ToString(iv).Replace("-", ""));
// decrypt
var decryptedData = new MemoryStream();
var aes = new RijndaelManaged();
aes.Mode = CipherMode.CFB;
aes.Key = key;
aes.IV = iv;
aes.Padding = PaddingMode.None;
var decryptor = new NoPaddingTransformWrapper(aes.CreateDecryptor());
using (var inputFile = File.OpenRead(inputFileName))
{
info.Add("original.size " + inputFile.Length);
info.Add("original.sha256 " + HashStream(inputFile));
using (var cryptoStream = new CryptoStream(inputFile, decryptor, CryptoStreamMode.Read))
{
cryptoStream.CopyTo(decryptedData);
}
info.Add("decrypted.size " + decryptedData.Length);
info.Add("decrypted.sha256 " + HashStream(decryptedData));
}
var outputDecryptedName = Path.ChangeExtension(outputBase, "decrypted");
File.WriteAllBytes(outputDecryptedName, decryptedData.ToArray());
// First 4 bytes are unknown. The next 2 bytes are the zlib header 789C. After that the raw deflate data follows.
var header = new byte[6];
if (decryptedData.Read(header, 0, header.Length) != header.Length)
throw new IOException("Did not read the full header");
if (header[4] != 0x78 || header[5] != 0x9C)//zlib header
throw new ApplicationException("Incorrect key/iv");
decryptedData.Position = 6;
// decompress using deflate
var unpackedData = new MemoryStream();
int revision;
using (var deflateStream = new DeflateStream(decryptedData, CompressionMode.Decompress, true))
{
deflateStream.CopyTo(unpackedData);
}
info.Add("unpacked.size " + unpackedData.Length);
info.Add("unpacked.sha256 " + HashStream(unpackedData));
using (var reader = new BinaryReader(unpackedData, Encoding.Unicode, true))
{
unpackedData.Position = 0x0C;
revision = reader.ReadInt32();
info.Insert(1, "revision " + revision);
}
File.WriteAllLines(Path.ChangeExtension(outputBase, revision + ".dcinfo"), info);
File.WriteAllBytes(Path.ChangeExtension(outputBase, revision + ".unpacked"), unpackedData.ToArray());
File.Delete(outputDecryptedName);
}
