def CPAExperiment(total):
start = time.time()
generator = InitialGenerator(True)
key = getDefaultKey()
baseMessage = get_random_bytes(AES.block_size)
baseCipher, baseIV = _encryptionOracle_unsecure([baseMessage], key, generator)[0]
win = 0
iv = baseIV
for i in range(total):
nextIV = compute_next_IV(iv)
prepared = prepare_message(baseMessage, baseIV, nextIV)
random = get_random_bytes(AES.block_size)
while random is prepared:
random = get_random_bytes(AES.block_size)
output, bit = _challenge_unsecure([prepared, random], key, generator)
cipher, iv = output[0], output[1]
guessed = guess_bit(baseCipher,cipher)
if guessed == bit:
win += 1
end = time.time()
print(f"Guessed [{win}] of [{total}] attempts [{win*100/total}%].")
print(f"Guessed in [{end - start} s]")
print(f"Average time [{(end - start)/total} s]")
def get_key(args):
if args.path is None or args.password is None or args.alias is None:
print("Using default key!")
key = getDefaultKey()
else:
key = getKey(args.path, args.alias, args.password)
return key
def test_EAX(self):
aes = AES_util()
mode = "EAX"
key = getDefaultKey()
message = get_random_bytes(AES.block_size)
cipher, iv = aes.encrypt(message, mode, key)
decrypted = aes.decrypt(cipher, mode, key, iv)
self.assertEqual(message, decrypted)
self.assertNotEqual(message, cipher)
def __init__(self, init=None):
if init is None:
self.init = InitialGenerator()
else:
self.init = init
self.key = getDefaultKey()