public int TransformBlock(byte[] inputBuffer, int inputOffset, int inputCount, byte[] outputBuffer, int outputOffset)
{
byte[] tempBuffer = new byte[64];
int encryptedBytes = 0;
while (inputCount > 0)
{
Salsa20Transformation.SalsaBlock(tempBuffer, _state, _rounds);
Salsa20Transformation.IncrementSalsaState(_state);
int blockSize = Math.Min(InputBlockSize, inputCount);
for (int i = 0; i < blockSize; i++)
{
outputBuffer[outputOffset + i] = (byte)(inputBuffer[inputOffset + i] ^ tempBuffer[i]);
}
encryptedBytes += blockSize;
inputCount -= InputBlockSize;
outputOffset += InputBlockSize;
inputOffset += InputBlockSize;
}
return(encryptedBytes);
}
public Salsa20Encryptor(byte[] key, byte[] iv, uint rounds)
{
if (key.Length != 16 && key.Length != 32)
{
throw new ArgumentException($"Key length not supported: {key.Length}");
}
if (iv.Length < 8)
{
throw new ArgumentException($"Invalid initialization vector size: {iv.Length}");
}
_rounds = rounds;
_state = Salsa20Transformation.CreateInitialState(key, iv);
}
