public bool CheckSignature(string message, int w, BigInteger s)
{
BigInteger m = new GostHash().CalculateHash(message.ToCharArray());
BigInteger v = BigInteger.Pow(m, _q - 2) % _q;
int z1 = (int)((s * v) % _q);
int z2 = (int)(((_q - w) * v) % _q);
BigInteger u = ((BigInteger.Pow(_a, z1) * BigInteger.Pow(_y, z2)) % _p % _q);
return(w == u);
}
public (int, BigInteger) Sign(string message)
{
BigInteger m = new GostHash().CalculateHash(message.ToCharArray());
int w = (int)(BigInteger.Pow(_a, _k) % _p);
w = w % _q;
BigInteger s = (_x * w + _k * m) % _q;
return(w, s);
}
