def test_signature(self):
k1 = new_key()
k2 = new_key()
k3 = new_key()
sender = Encryptor(k1, k2.publickey())
receiver = Encryptor(k2, k1.publickey())
deceiver = Encryptor(k3, k2.publickey())
message = b"Erised stra ehru oyt ube cafru oyt on wohsi"
with print_key_on_error(sender, receiver, deceiver):
cipher_text = sender.encrypt(message)
decrypted_message, signature = receiver.decrypt(cipher_text)
self.assertTrue(receiver.verify_message(decrypted_message, signature))
deceiver_text = deceiver.encrypt(message)
decrypted_message, signature = receiver.decrypt(deceiver_text)
self.assertFalse(receiver.verify_message(decrypted_message, signature))
_, real_encrypted_message, _ = receiver.split_cipher_text(cipher_text)
deceiver_aes, _, deceiver_signature = receiver.split_cipher_text(deceiver_text)
cipher_text = deceiver_aes + real_encrypted_message + deceiver_signature
decrypted_message, signature = receiver.decrypt(cipher_text)
self.assertFalse(receiver.verify_message(decrypted_message, signature))
def test_encrypt_decrypt(self):
k1 = new_key()
k2 = new_key()
k3 = new_key()
sender = Encryptor(k1, k2.publickey())
receiver = Encryptor(k2, k1.publickey())
message = b"In the Land of Mordor where the Shadows lie." \
b"One Ring to rule them all, One Ring to find them,\n" \
b"One Ring to bring them all and in the darkness bind them\n" \
b"In the Land of Mordor where the Shadows lie.\n"
with print_key_on_error(sender, receiver):
cipher_text = sender.encrypt(message)
decrypted_message, signature = receiver.decrypt(cipher_text)
self.assertEqual(message, decrypted_message)
with self.assertRaises(Exception):
mangled_cipher_text = cipher_text[2:4] + cipher_text[:2] + cipher_text[4:]
receiver.decrypt(mangled_cipher_text)