private static async Task <(MemoryStream output, IMS2SizeHeader size)> InternalGetEncryptionStreamAsync(Stream input, long inputSize, IBufferedCipher cipher, long headerSize)
{
byte[] inputBytes = new byte[inputSize];
int read = await input.ReadAsync(inputBytes, 0, (int)inputSize).ConfigureAwait(false);
if (inputSize != read)
{
throw new EndOfStreamException();
}
using var msInput = new MemoryStream(inputBytes);
using var cs = new CipherStream(msInput, cipher, null);
using var ms = new MemoryStream();
var output = new MemoryStream();
await cs.CopyToAsync(ms).ConfigureAwait(false);
var data = ms.ToArray();
var encoder = new Base64Encoder();
encoder.Encode(data, 0, data.Length, output);
var header = new MS2SizeHeader(output.Length, inputSize, headerSize);
output.Position = 0;
return(output, header);
}
private static Task <MS2Archive> LoadMS2F(MS2CryptoMode cryptoMode, BinaryReader br, string name, MemoryMappedFile dataMemoryMappedFile)
{
return(Task.Run(async() =>
{
uint unk = br.ReadUInt32(); // TODO: unknown/unused?
uint dataCompressedSize = br.ReadUInt32() | br.ReadUInt32();
uint dataEncodedSize = br.ReadUInt32() | br.ReadUInt32();
uint size = br.ReadUInt32() | br.ReadUInt32();
uint compressedSize = br.ReadUInt32() | br.ReadUInt32();
uint encodedSize = br.ReadUInt32() | br.ReadUInt32();
uint fileCount = br.ReadUInt32() | br.ReadUInt32();
uint dataSize = br.ReadUInt32() | br.ReadUInt32();
if (unk != 0)
{
Logger.Debug($"Archive header unk is \"{unk}\".");
}
var header = new MS2SizeHeader(encodedSize, compressedSize, size);
var data = new MS2SizeHeader(dataEncodedSize, dataCompressedSize, dataSize);
Logger.Verbose($"There are {fileCount} files in the archive.");
List <MS2File> files = await LoadFiles(cryptoMode, header, data, fileCount, br, dataMemoryMappedFile).ConfigureAwait(false);
var archive = new MS2Archive(cryptoMode, header, data, name, dataMemoryMappedFile, files);
return archive;
}));
}
private MS2Archive(MS2CryptoMode cryptoMode, MS2SizeHeader header, MS2SizeHeader data, string name, MemoryMappedFile dataFile, List <MS2File> files)
{
this.Name = name;
this.DataFile = dataFile;
this.CryptoMode = cryptoMode;
this.Header = header;
this.Data = data;
this.Files = files;
}
public static async Task <(byte[] Bytes, MS2SizeHeader Header)> EncryptDataToDataAsync(MS2CryptoMode cryptoMode, bool compress, byte[] bytes)
{
if (compress)
{
byte[] compressedBytes = await Task.Run(() => Compress(bytes)).ConfigureAwait(false);
byte[] encryptedBytes = await Task.Run(() => EncryptNoCompress(cryptoMode, compressedBytes, (uint)compressedBytes.Length)).ConfigureAwait(false);
var header = new MS2SizeHeader((uint)encryptedBytes.Length, (uint)compressedBytes.Length, (uint)bytes.Length);
return(encryptedBytes, header);
}
else
{
byte[] encryptedBytes = await Task.Run(() => EncryptNoCompress(cryptoMode, bytes, (uint)bytes.Length)).ConfigureAwait(false);
var header = new MS2SizeHeader((uint)encryptedBytes.Length, (uint)bytes.Length, (uint)bytes.Length);
return(encryptedBytes, header);
}
}
private static Task <MS2Archive> LoadNS2F(MS2CryptoMode cryptoMode, BinaryReader br, string name, MemoryMappedFile dataMemoryMappedFile)
{
return(Task.Run(async() =>
{
uint fileCount = br.ReadUInt32();
uint dataCompressedSize = br.ReadUInt32() | br.ReadUInt32();
uint dataEncodedSize = br.ReadUInt32() | br.ReadUInt32();
uint size = br.ReadUInt32() | br.ReadUInt32();
uint compressedSize = br.ReadUInt32() | br.ReadUInt32();
uint encodedSize = br.ReadUInt32() | br.ReadUInt32();
uint dataSize = br.ReadUInt32() | br.ReadUInt32();
var header = new MS2SizeHeader(encodedSize, compressedSize, size);
var data = new MS2SizeHeader(dataEncodedSize, dataCompressedSize, dataSize);
List <MS2File> files = await LoadFiles(cryptoMode, header, data, fileCount, br, dataMemoryMappedFile).ConfigureAwait(false);
var archive = new MS2Archive(cryptoMode, header, data, name, dataMemoryMappedFile, files);
return archive;
}));
}
public static Task <Stream> DecryptStreamToStreamAsync(MS2CryptoMode cryptoMode, MS2SizeHeader header, bool isCompressed, Stream stream)
{
return(DecryptStreamToDataAsync(cryptoMode, header, isCompressed, stream).ContinueWith <Stream>(t => new MemoryStream(t.Result)));
}
public static async Task <byte[]> DecryptDataToDataAsync(MS2CryptoMode cryptoMode, MS2SizeHeader header, bool isCompressed, byte[] bytes)
{
if (header.EncodedSize == 0 || header.CompressedSize == 0 || header.Size == 0)
{
return(new byte[0]);
}
if (isCompressed)
{
return(await Task.Run(() => Decrypt(cryptoMode, bytes, header.CompressedSize, header.Size)).ConfigureAwait(false));
}
else
{
return(await Task.Run(() => DecryptNoDecompress(cryptoMode, bytes, header.Size)).ConfigureAwait(false));
}
}
public static async Task <byte[]> DecryptStreamToDataAsync(MS2CryptoMode cryptoMode, MS2SizeHeader header, bool isCompressed, Stream stream)
{
if (header.EncodedSize == 0 || header.CompressedSize == 0 || header.Size == 0)
{
return(new byte[0]);
}
byte[] buffer = new byte[header.EncodedSize];
uint readBytes = (uint)await stream.ReadAsync(buffer, 0, (int)header.EncodedSize).ConfigureAwait(false);
if (readBytes != header.EncodedSize)
{
throw new Exception("Data length mismatch when reading data.");
}
return(await DecryptDataToDataAsync(cryptoMode, header, isCompressed, buffer).ConfigureAwait(false));
}
internal static MS2FileHeader Create(uint id, uint offset, CompressionType compressionType, MS2SizeHeader header) => new MS2FileHeader(header.EncodedSize, header.CompressedSize, header.Size, id, offset, compressionType);
private static async Task <List <MS2File> > LoadFiles(MS2CryptoMode cryptoMode, MS2SizeHeader header, MS2SizeHeader data, uint fileCount, BinaryReader br, MemoryMappedFile dataMemoryMappedFile)
{
var files = new List <MS2File>((int)fileCount);
// TODO: are those always compressed?
using (Stream headerStream = await DecryptStreamToStreamAsync(cryptoMode, header, true, br.BaseStream).ConfigureAwait(false))
using (Stream dataStream = await DecryptStreamToStreamAsync(cryptoMode, data, true, br.BaseStream).ConfigureAwait(false))
{
for (int i = 0; i < fileCount; i++)
{
files.Add(await MS2File.Load(cryptoMode, headerStream, dataStream, dataMemoryMappedFile).ConfigureAwait(false));
}
return(files);
}
}
