def test_all(self):
for _ in range(20):
x, y = random.randrange(2**256), random.randrange(2**256)
self.assertFalse(ec.is_curve_point((x,y)))
G_x = ec.multiply(ec.G, x)
G_y = ec.multiply(ec.G, y)
self.assertTrue(ec.is_curve_point(G_x))
self.assertEqual(
ec.multiply(G_x, y)[0],
ec.multiply(G_y, x)[0]
)
self.assertEqual(
ec.add(G_x, G_y)[0],
ec.multiply(ec.G, ec.add_scalar(x, y))[0]
)
self.assertEqual(
ec.substract(G_x, G_y)[0],
ec.multiply(ec.G, ec.substract_scalar(x, y))[0]
)
self.assertEqual(ec.G[0], ec.multiply(ec.divide(ec.G, x), x)[0])
def derive_xpriv(k, i):
i = int(i)
pub = ecdsa.priv_to_pub(k['priv'])
pub_ser = ecdsa.serialize_pub(pub)
priv_ser = ecdsa.serialize_priv(k['priv'])
if i >= 2**31:
hmacdata = b'\x00' + priv_ser + convert.int_to_bytes(i, 4)
else:
hmacdata = pub_ser + convert.int_to_bytes(i, 4)
I = hmac.new(k['chaincode'], hmacdata, hashlib.sha512).digest()
return {
'depth': k['depth'] + 1,
'fingerprint': hashes.hash160(pub_ser)[:4],
'i': i,
'chaincode': I[32:],
'priv': ec.add_scalar(k['priv'], ecdsa.deserialize_priv(I[:32]))
}