def test_decrypt_acvp(self):
for testVector in testVectors_ACVP_AES_FF3_1:
with self.subTest(testVector=testVector):
c = FF3Cipher.withCustomAlphabet(testVector['key'],
testVector['tweak'],
testVector['alphabet'])
s = c.decrypt(testVector['ciphertext'])
self.assertEqual(s, testVector['plaintext'])
def test_custom_alphabet(self):
alphabet = "⁰¹²³⁴⁵⁶⁷⁸⁹"
key = "EF4359D8D580AA4F7F036D6F04FC6A94"
tweak = "D8E7920AFA330A73"
plaintext = "⁸⁹⁰¹²¹²³⁴⁵⁶⁷⁸⁹⁰⁰⁰⁰"
ciphertext = "⁷⁵⁰⁹¹⁸⁸¹⁴⁰⁵⁸⁶⁵⁴⁶⁰⁷"
c = FF3Cipher.withCustomAlphabet(key, tweak, alphabet)
s = c.encrypt(plaintext)
self.assertEqual(s, ciphertext)
x = c.decrypt(s)
self.assertEqual(x, plaintext)
def test_german(self):
"""
Test the German alphabet with a radix of 70. German consists of the latin alphabet
plus four additional letters, each of which have uppercase and lowercase letters
"""
german_alphabet = string.digits + string.ascii_lowercase + string.ascii_uppercase + "ÄäÖöÜüẞß"
key = "EF4359D8D580AA4F7F036D6F04FC6A94"
tweak = "D8E7920AFA330A73"
plaintext = "liebeGrüße"
ciphertext = "5kÖQbairXo"
c = FF3Cipher.withCustomAlphabet(key, tweak, alphabet=german_alphabet)
s = c.encrypt(plaintext)
self.assertEqual(s, ciphertext)
x = c.decrypt(s)
self.assertEqual(x, plaintext)
def test_whole_domain(self):
test_cases = [
# (radix, plaintext_len, alphabet (None means default))
(2, 10, None),
(3, 6, None),
(10, 3, None),
(17, 3, None),
(62, 2, None),
(3, 7, "ABC"),
]
max_radix = max(radix for radix, plaintext_len, alphabet in test_cases)
# Temporarily reduce DOMAIN_MIN to make testing fast
domain_min_orig = FF3Cipher.DOMAIN_MIN
FF3Cipher.DOMAIN_MIN = max_radix + 1
key = "EF4359D8D580AA4F7F036D6F04FC6A94"
tweak = "D8E7920AFA330A73"
for radix, plaintext_len, alphabet in test_cases:
if alphabet is None:
c = FF3Cipher(key, tweak, radix=radix)
else:
c = FF3Cipher.withCustomAlphabet(key, tweak, alphabet=alphabet)
self.subTest(radix=radix, plaintext_len=plaintext_len)
# Integer representations of each possible plaintext
plaintexts_as_ints = list(range(radix**plaintext_len))
# String representations of each possible plaintext
all_possible_plaintexts = [
encode_int_r(i, alphabet=c.alphabet, length=plaintext_len)
for i in plaintexts_as_ints
]
# Check that plaintexts decode correctly
self.assertEqual([
decode_int_r(plaintext, c.alphabet)
for plaintext in all_possible_plaintexts
], plaintexts_as_ints)
# Check that there are no duplicate plaintexts
self.assertEqual(len(set(all_possible_plaintexts)),
len(all_possible_plaintexts))
# Check that all plaintexts have the expected length
self.assertTrue(
all(
len(plaintext) == plaintext_len
for plaintext in all_possible_plaintexts))
all_possible_ciphertexts = [
c.encrypt(plaintext) for plaintext in all_possible_plaintexts
]
# Check that encryption is format-preserving
self.assertEqual(set(all_possible_plaintexts),
set(all_possible_ciphertexts))
all_decrypted_ciphertexts = [
c.decrypt(ciphertext)
for ciphertext in all_possible_ciphertexts
]
# Check that encryption and decryption are inverses
self.assertEqual(all_possible_plaintexts,
all_decrypted_ciphertexts)
# Note: it would be mathematically redundant to also check first decrypting
# and then encrypting, since permutations have only two-sided inverses.
# Restore original DOMAIN_MIN value
FF3Cipher.DOMAIN_MIN = domain_min_orig