public static void crypto_sign(
byte[] sig, int sigoffset,
byte[] m, int moffset, int mlen,
byte[] sk, int skoffset)
{
byte[] az, r, hram;
GroupElementP3 R;
var hasher = new Sha512();
{
hasher.Update(sk, skoffset, 32);
az = hasher.Finalize();
ScalarOperations.sc_clamp(az, 0);
hasher.Init();
hasher.Update(az, 32, 32);
hasher.Update(m, moffset, mlen);
r = hasher.Finalize();
ScalarOperations.sc_reduce(r);
GroupOperations.ge_scalarmult_base(out R, r, 0);
GroupOperations.ge_p3_tobytes(sig, sigoffset, ref R);
hasher.Init();
hasher.Update(sig, sigoffset, 32);
hasher.Update(sk, skoffset + 32, 32);
hasher.Update(m, moffset, mlen);
hram = hasher.Finalize();
ScalarOperations.sc_reduce(hram);
var s = new byte[32]; //todo: remove allocation
Array.Copy(sig, sigoffset + 32, s, 0, 32);
ScalarOperations.sc_muladd(s, hram, az, r);
Array.Copy(s, 0, sig, sigoffset + 32, 32);
CryptoBytes.Wipe(s);
}
}
