public Encryption(Key key, IV iv)
{
aes.Mode = CipherMode.CBC;
aes.Padding = PaddingMode.None;
aes.Key = key.key;
aes.IV = iv.iv;
}
public void EncryptFileWithPadding(FileStream input, int contentID, FileStream output, int blockSize)
{
BigEndianMemoryStream ivStream = new BigEndianMemoryStream(0x10);
ivStream.WriteBigEndian((short)contentID);
IV iv = new IV(ivStream.GetBuffer());
EncryptSingleFile(input, output, input.Length, iv, blockSize);
}
public void EncryptFileWithPadding(FST fst, string outputFilename, short contentID, int blockSize)
{
using FileStream output = new FileStream(outputFilename, FileMode.Create);
MemoryStream input = new MemoryStream(fst.GetAsData());
BigEndianMemoryStream ivStream = new BigEndianMemoryStream(0x10);
ivStream.WriteBigEndian(contentID);
IV iv = new IV(ivStream.GetBuffer());
EncryptSingleFile(input, output, fst.GetDataSize(), iv, blockSize);
}
private void EncryptSingleFile(Stream input, Stream output, long inputLength, IV iv, int blockSize)
{
aes.IV = iv.iv;
long targetSize = Utils.Align(inputLength, blockSize);
int cur_position = 0;
do
{
byte[] blockBuffer = new byte[blockSize];
input.Read(blockBuffer, 0, blockSize);
blockBuffer = Encrypt(blockBuffer);
aes.IV = Utils.CopyOfRange(blockBuffer, blockSize - 16, blockSize);
cur_position += blockSize;
output.Write(blockBuffer);
} while (cur_position < targetSize);
}