_slowmath.py 文件源码

def _sign(self, m, k):   # alias for _decrypt
        # SECURITY TODO - We _should_ be computing SHA1(m), but we don't because that's the API.
        if not self.has_private():
            raise TypeError("No private key")
        if not (1L < k < self.q):
            raise ValueError("k is not between 2 and q-1")
        inv_k = inverse(k, self.q)   # Compute k**-1 mod q
        r = pow(self.g, k, self.p) % self.q  # r = (g**k mod p) mod q
        s = (inv_k * (m + self.x * r)) % self.q
        return (r, s)