private byte[] Hash(SequencePool sequencePool, BigInteger sharedSecret, byte[] exchangeHash, byte c, byte[] sessionId, int hashLength)
{
// https://tools.ietf.org/html/rfc4253#section-7.2
byte[] hashRv = new byte[hashLength];
int hashOffset = 0;
// TODO: handle 'If the key length needed is longer than the output of the HASH'
// HASH(K || H || c || session_id)
using Sequence sequence = sequencePool.RentSequence();
var writer = new SequenceWriter(sequence);
writer.WriteMPInt(sharedSecret);
writer.Write(exchangeHash);
writer.WriteByte(c);
writer.Write(sessionId);
using IncrementalHash hash = IncrementalHash.CreateHash(_hashAlgorithmName);
foreach (var segment in sequence.AsReadOnlySequence())
{
hash.AppendData(segment.Span);
}
byte[] K1 = hash.GetHashAndReset();
Append(hashRv, K1, ref hashOffset);
while (hashOffset != hashRv.Length)
{
// TODO: handle 'If the key length needed is longer than the output of the HASH'
// K3 = HASH(K || H || K1 || K2)
throw new NotSupportedException();
}
return(hashRv);
public void Transform(Span <byte> prefix, ReadOnlySequence <byte> data, Span <byte> suffix, Sequence output)
{
var writer = new SequenceWriter(output);
writer.Write(prefix);
writer.Write(data);
writer.Write(suffix);
}
