def verify(self, msg, signature, y):
r, s = signature
# assert 0 < r < self.q
assert 0 < s < self.q
w = modinv(s, self.q)
u1 = (sha1num(msg) * w) % self.q
u2 = (r * w) % self.q
v = (pow(self.g, u1, self.p) * pow(y, u2, self.p)) % self.p % self.q
return v == r
def sign(self, msg, x):
hash = sha1num(msg)
return self.sign_hash(hash, x)