/// <summary>
/// Updates internal state with data from the provided array.
/// </summary>
/// <param name="data">Array of bytes</param>
/// <param name="index">Offset of byte sequence</param>
/// <param name="length">Sequence length</param>
public void Update(byte[] data, int index, int length)
{
Contract.Requires <ArgumentNullException>(data != null);
Contract.Requires <ArgumentOutOfRangeException>(index >= 0 && length >= 0);
Contract.Requires <ArgumentException>((index + length) <= data.Length);
Array16 <ulong> block;
int bytesInBuffer = (int)_totalBytes & (BlockSize - 1);
_totalBytes += (uint)length;
if (_totalBytes >= ulong.MaxValue / 8)
{
throw new InvalidOperationException("Too much data");
}
// Fill existing buffer
if (bytesInBuffer != 0)
{
var toCopy = Math.Min(BlockSize - bytesInBuffer, length);
Buffer.BlockCopy(data, index, _buffer, bytesInBuffer, toCopy);
index += toCopy;
length -= toCopy;
bytesInBuffer += toCopy;
if (bytesInBuffer == BlockSize)
{
ByteIntegerConverter.Array16LoadBigEndian64(out block, _buffer, 0);
Sha512Internal.Core(out _state, ref _state, ref block);
CryptoBytes.InternalWipe(_buffer, 0, _buffer.Length);
bytesInBuffer = 0;
}
}
// Hash complete blocks without copying
while (length >= BlockSize)
{
ByteIntegerConverter.Array16LoadBigEndian64(out block, data, index);
Sha512Internal.Core(out _state, ref _state, ref block);
index += BlockSize;
length -= BlockSize;
}
// Copy remainder into buffer
if (length > 0)
{
Buffer.BlockCopy(data, index, _buffer, bytesInBuffer, length);
}
}