Edit File: test_EAX.py
# =================================================================== # # Copyright (c) 2015, Legrandin <helderijs@gmail.com> # All rights reserved. # # Redistribution and use in source and binary forms, with or without # modification, are permitted provided that the following conditions # are met: # # 1. Redistributions of source code must retain the above copyright # notice, this list of conditions and the following disclaimer. # 2. Redistributions in binary form must reproduce the above copyright # notice, this list of conditions and the following disclaimer in # the documentation and/or other materials provided with the # distribution. # # THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS # "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT # LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS # FOR A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE # COPYRIGHT HOLDER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, # INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, # BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; # LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER # CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT # LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN # ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE # POSSIBILITY OF SUCH DAMAGE. # =================================================================== import unittest from binascii import unhexlify from Crypto.SelfTest.st_common import list_test_cases from Crypto.SelfTest.loader import load_test_vectors_wycheproof from Crypto.Util.py3compat import tobytes, bchr from Crypto.Cipher import AES, DES3 from Crypto.Hash import SHAKE128 from Crypto.Util.strxor import strxor def get_tag_random(tag, length): return SHAKE128.new(data=tobytes(tag)).read(length) class EaxTests(unittest.TestCase): key_128 = get_tag_random("key_128", 16) key_192 = get_tag_random("key_192", 16) nonce_96 = get_tag_random("nonce_128", 12) data_128 = get_tag_random("data_128", 16) def test_loopback_128(self): cipher = AES.new(self.key_128, AES.MODE_EAX, nonce=self.nonce_96) pt = get_tag_random("plaintext", 16 * 100) ct = cipher.encrypt(pt) cipher = AES.new(self.key_128, AES.MODE_EAX, nonce=self.nonce_96) pt2 = cipher.decrypt(ct) self.assertEqual(pt, pt2) def test_loopback_64(self): cipher = DES3.new(self.key_192, DES3.MODE_EAX, nonce=self.nonce_96) pt = get_tag_random("plaintext", 8 * 100) ct = cipher.encrypt(pt) cipher = DES3.new(self.key_192, DES3.MODE_EAX, nonce=self.nonce_96) pt2 = cipher.decrypt(ct) self.assertEqual(pt, pt2) def test_nonce(self): # If not passed, the nonce is created randomly cipher = AES.new(self.key_128, AES.MODE_EAX) nonce1 = cipher.nonce cipher = AES.new(self.key_128, AES.MODE_EAX) nonce2 = cipher.nonce self.assertEqual(len(nonce1), 16) self.assertNotEqual(nonce1, nonce2) cipher = AES.new(self.key_128, AES.MODE_EAX, self.nonce_96) ct = cipher.encrypt(self.data_128) cipher = AES.new(self.key_128, AES.MODE_EAX, nonce=self.nonce_96) self.assertEqual(ct, cipher.encrypt(self.data_128)) def test_nonce_must_be_bytes(self): self.assertRaises(TypeError, AES.new, self.key_128, AES.MODE_EAX, nonce=u'test12345678') def test_nonce_length(self): # nonce can be of any length (but not empty) self.assertRaises(ValueError, AES.new, self.key_128, AES.MODE_EAX, nonce=b"") for x in range(1, 128): cipher = AES.new(self.key_128, AES.MODE_EAX, nonce=bchr(1) * x) cipher.encrypt(bchr(1)) def test_block_size_128(self): cipher = AES.new(self.key_128, AES.MODE_EAX, nonce=self.nonce_96) self.assertEqual(cipher.block_size, AES.block_size) def test_block_size_64(self): cipher = DES3.new(self.key_192, AES.MODE_EAX, nonce=self.nonce_96) self.assertEqual(cipher.block_size, DES3.block_size) def test_nonce_attribute(self): cipher = AES.new(self.key_128, AES.MODE_EAX, nonce=self.nonce_96) self.assertEqual(cipher.nonce, self.nonce_96) # By default, a 16 bytes long nonce is randomly generated nonce1 = AES.new(self.key_128, AES.MODE_EAX).nonce nonce2 = AES.new(self.key_128, AES.MODE_EAX).nonce self.assertEqual(len(nonce1), 16) self.assertNotEqual(nonce1, nonce2) def test_unknown_parameters(self): self.assertRaises(TypeError, AES.new, self.key_128, AES.MODE_EAX, self.nonce_96, 7) self.assertRaises(TypeError, AES.new, self.key_128, AES.MODE_EAX, nonce=self.nonce_96, unknown=7) # But some are only known by the base cipher # (e.g. use_aesni consumed by the AES module) AES.new(self.key_128, AES.MODE_EAX, nonce=self.nonce_96, use_aesni=False) def test_null_encryption_decryption(self): for func in "encrypt", "decrypt": cipher = AES.new(self.key_128, AES.MODE_EAX, nonce=self.nonce_96) result = getattr(cipher, func)(b"") self.assertEqual(result, b"") def test_either_encrypt_or_decrypt(self): cipher = AES.new(self.key_128, AES.MODE_EAX, nonce=self.nonce_96) cipher.encrypt(b"") self.assertRaises(TypeError, cipher.decrypt, b"") cipher = AES.new(self.key_128, AES.MODE_EAX, nonce=self.nonce_96) cipher.decrypt(b"") self.assertRaises(TypeError, cipher.encrypt, b"") def test_data_must_be_bytes(self): cipher = AES.new(self.key_128, AES.MODE_EAX, nonce=self.nonce_96) self.assertRaises(TypeError, cipher.encrypt, u'test1234567890-*') cipher = AES.new(self.key_128, AES.MODE_EAX, nonce=self.nonce_96) self.assertRaises(TypeError, cipher.decrypt, u'test1234567890-*') def test_mac_len(self): # Invalid MAC length self.assertRaises(ValueError, AES.new, self.key_128, AES.MODE_EAX, nonce=self.nonce_96, mac_len=2-1) self.assertRaises(ValueError, AES.new, self.key_128, AES.MODE_EAX, nonce=self.nonce_96, mac_len=16+1) # Valid MAC length for mac_len in range(2, 16 + 1): cipher = AES.new(self.key_128, AES.MODE_EAX, nonce=self.nonce_96, mac_len=mac_len) _, mac = cipher.encrypt_and_digest(self.data_128) self.assertEqual(len(mac), mac_len) # Default MAC length cipher = AES.new(self.key_128, AES.MODE_EAX, nonce=self.nonce_96) _, mac = cipher.encrypt_and_digest(self.data_128) self.assertEqual(len(mac), 16) def test_invalid_mac(self): from Crypto.Util.strxor import strxor_c cipher = AES.new(self.key_128, AES.MODE_EAX, nonce=self.nonce_96) ct, mac = cipher.encrypt_and_digest(self.data_128) invalid_mac = strxor_c(mac, 0x01) cipher = AES.new(self.key_128, AES.MODE_EAX, nonce=self.nonce_96) self.assertRaises(ValueError, cipher.decrypt_and_verify, ct, invalid_mac) def test_hex_mac(self): cipher = AES.new(self.key_128, AES.MODE_EAX, nonce=self.nonce_96) mac_hex = cipher.hexdigest() self.assertEqual(cipher.digest(), unhexlify(mac_hex)) cipher = AES.new(self.key_128, AES.MODE_EAX, nonce=self.nonce_96) cipher.hexverify(mac_hex) def test_message_chunks(self): # Validate that both associated data and plaintext/ciphertext # can be broken up in chunks of arbitrary length auth_data = get_tag_random("authenticated data", 127) plaintext = get_tag_random("plaintext", 127) cipher = AES.new(self.key_128, AES.MODE_EAX, nonce=self.nonce_96) cipher.update(auth_data) ciphertext, ref_mac = cipher.encrypt_and_digest(plaintext) def break_up(data, chunk_length): return [data[i:i+chunk_length] for i in range(0, len(data), chunk_length)] # Encryption for chunk_length in 1, 2, 3, 7, 10, 13, 16, 40, 80, 128: cipher = AES.new(self.key_128, AES.MODE_EAX, nonce=self.nonce_96) for chunk in break_up(auth_data, chunk_length): cipher.update(chunk) pt2 = b"" for chunk in break_up(ciphertext, chunk_length): pt2 += cipher.decrypt(chunk) self.assertEqual(plaintext, pt2) cipher.verify(ref_mac) # Decryption for chunk_length in 1, 2, 3, 7, 10, 13, 16, 40, 80, 128: cipher = AES.new(self.key_128, AES.MODE_EAX, nonce=self.nonce_96) for chunk in break_up(auth_data, chunk_length): cipher.update(chunk) ct2 = b"" for chunk in break_up(plaintext, chunk_length): ct2 += cipher.encrypt(chunk) self.assertEqual(ciphertext, ct2) self.assertEqual(cipher.digest(), ref_mac) def test_bytearray(self): # Encrypt key_ba = bytearray(self.key_128) nonce_ba = bytearray(self.nonce_96) header_ba = bytearray(self.data_128) data_ba = bytearray(self.data_128) cipher1 = AES.new(self.key_128, AES.MODE_EAX, nonce=self.nonce_96) cipher1.update(self.data_128) ct = cipher1.encrypt(self.data_128) tag = cipher1.digest() cipher2 = AES.new(key_ba, AES.MODE_EAX, nonce=nonce_ba) key_ba[:3] = b'\xFF\xFF\xFF' nonce_ba[:3] = b'\xFF\xFF\xFF' cipher2.update(header_ba) header_ba[:3] = b'\xFF\xFF\xFF' ct_test = cipher2.encrypt(data_ba) data_ba[:3] = b'\x99\x99\x99' tag_test = cipher2.digest() self.assertEqual(ct, ct_test) self.assertEqual(tag, tag_test) self.assertEqual(cipher1.nonce, cipher2.nonce) # Decrypt key_ba = bytearray(self.key_128) nonce_ba = bytearray(self.nonce_96) header_ba = bytearray(self.data_128) ct_ba = bytearray(ct) tag_ba = bytearray(tag) del data_ba cipher3 = AES.new(key_ba, AES.MODE_EAX, nonce=nonce_ba) key_ba[:3] = b'\xFF\xFF\xFF' nonce_ba[:3] = b'\xFF\xFF\xFF' cipher3.update(header_ba) header_ba[:3] = b'\xFF\xFF\xFF' pt_test = cipher3.decrypt(ct_ba) ct_ba[:3] = b'\xFF\xFF\xFF' cipher3.verify(tag_ba) self.assertEqual(pt_test, self.data_128) def test_memoryview(self): # Encrypt key_mv = memoryview(bytearray(self.key_128)) nonce_mv = memoryview(bytearray(self.nonce_96)) header_mv = memoryview(bytearray(self.data_128)) data_mv = memoryview(bytearray(self.data_128)) cipher1 = AES.new(self.key_128, AES.MODE_EAX, nonce=self.nonce_96) cipher1.update(self.data_128) ct = cipher1.encrypt(self.data_128) tag = cipher1.digest() cipher2 = AES.new(key_mv, AES.MODE_EAX, nonce=nonce_mv) key_mv[:3] = b'\xFF\xFF\xFF' nonce_mv[:3] = b'\xFF\xFF\xFF' cipher2.update(header_mv) header_mv[:3] = b'\xFF\xFF\xFF' ct_test = cipher2.encrypt(data_mv) data_mv[:3] = b'\x99\x99\x99' tag_test = cipher2.digest() self.assertEqual(ct, ct_test) self.assertEqual(tag, tag_test) self.assertEqual(cipher1.nonce, cipher2.nonce) # Decrypt key_mv = memoryview(bytearray(self.key_128)) nonce_mv = memoryview(bytearray(self.nonce_96)) header_mv = memoryview(bytearray(self.data_128)) ct_mv = memoryview(bytearray(ct)) tag_mv = memoryview(bytearray(tag)) del data_mv cipher3 = AES.new(key_mv, AES.MODE_EAX, nonce=nonce_mv) key_mv[:3] = b'\xFF\xFF\xFF' nonce_mv[:3] = b'\xFF\xFF\xFF' cipher3.update(header_mv) header_mv[:3] = b'\xFF\xFF\xFF' pt_test = cipher3.decrypt(ct_mv) ct_mv[:3] = b'\x99\x99\x99' cipher3.verify(tag_mv) self.assertEqual(pt_test, self.data_128) def test_output_param(self): pt = b'5' * 128 cipher = AES.new(self.key_128, AES.MODE_EAX, nonce=self.nonce_96) ct = cipher.encrypt(pt) tag = cipher.digest() output = bytearray(128) cipher = AES.new(self.key_128, AES.MODE_EAX, nonce=self.nonce_96) res = cipher.encrypt(pt, output=output) self.assertEqual(ct, output) self.assertEqual(res, None) cipher = AES.new(self.key_128, AES.MODE_EAX, nonce=self.nonce_96) res = cipher.decrypt(ct, output=output) self.assertEqual(pt, output) self.assertEqual(res, None) cipher = AES.new(self.key_128, AES.MODE_EAX, nonce=self.nonce_96) res, tag_out = cipher.encrypt_and_digest(pt, output=output) self.assertEqual(ct, output) self.assertEqual(res, None) self.assertEqual(tag, tag_out) cipher = AES.new(self.key_128, AES.MODE_EAX, nonce=self.nonce_96) res = cipher.decrypt_and_verify(ct, tag, output=output) self.assertEqual(pt, output) self.assertEqual(res, None) def test_output_param_memoryview(self): pt = b'5' * 128 cipher = AES.new(self.key_128, AES.MODE_EAX, nonce=self.nonce_96) ct = cipher.encrypt(pt) output = memoryview(bytearray(128)) cipher = AES.new(self.key_128, AES.MODE_EAX, nonce=self.nonce_96) cipher.encrypt(pt, output=output) self.assertEqual(ct, output) cipher = AES.new(self.key_128, AES.MODE_EAX, nonce=self.nonce_96) cipher.decrypt(ct, output=output) self.assertEqual(pt, output) def test_output_param_neg(self): LEN_PT = 16 pt = b'5' * LEN_PT cipher = AES.new(self.key_128, AES.MODE_EAX, nonce=self.nonce_96) ct = cipher.encrypt(pt) cipher = AES.new(self.key_128, AES.MODE_EAX, nonce=self.nonce_96) self.assertRaises(TypeError, cipher.encrypt, pt, output=b'0' * LEN_PT) cipher = AES.new(self.key_128, AES.MODE_EAX, nonce=self.nonce_96) self.assertRaises(TypeError, cipher.decrypt, ct, output=b'0' * LEN_PT) shorter_output = bytearray(LEN_PT - 1) cipher = AES.new(self.key_128, AES.MODE_EAX, nonce=self.nonce_96) self.assertRaises(ValueError, cipher.encrypt, pt, output=shorter_output) cipher = AES.new(self.key_128, AES.MODE_EAX, nonce=self.nonce_96) self.assertRaises(ValueError, cipher.decrypt, ct, output=shorter_output) class EaxFSMTests(unittest.TestCase): key_128 = get_tag_random("key_128", 16) nonce_96 = get_tag_random("nonce_128", 12) data_128 = get_tag_random("data_128", 16) def test_valid_init_encrypt_decrypt_digest_verify(self): # No authenticated data, fixed plaintext # Verify path INIT->ENCRYPT->DIGEST cipher = AES.new(self.key_128, AES.MODE_EAX, nonce=self.nonce_96) ct = cipher.encrypt(self.data_128) mac = cipher.digest() # Verify path INIT->DECRYPT->VERIFY cipher = AES.new(self.key_128, AES.MODE_EAX, nonce=self.nonce_96) cipher.decrypt(ct) cipher.verify(mac) def test_valid_init_update_digest_verify(self): # No plaintext, fixed authenticated data # Verify path INIT->UPDATE->DIGEST cipher = AES.new(self.key_128, AES.MODE_EAX, nonce=self.nonce_96) cipher.update(self.data_128) mac = cipher.digest() # Verify path INIT->UPDATE->VERIFY cipher = AES.new(self.key_128, AES.MODE_EAX, nonce=self.nonce_96) cipher.update(self.data_128) cipher.verify(mac) def test_valid_full_path(self): # Fixed authenticated data, fixed plaintext # Verify path INIT->UPDATE->ENCRYPT->DIGEST cipher = AES.new(self.key_128, AES.MODE_EAX, nonce=self.nonce_96) cipher.update(self.data_128) ct = cipher.encrypt(self.data_128) mac = cipher.digest() # Verify path INIT->UPDATE->DECRYPT->VERIFY cipher = AES.new(self.key_128, AES.MODE_EAX, nonce=self.nonce_96) cipher.update(self.data_128) cipher.decrypt(ct) cipher.verify(mac) def test_valid_init_digest(self): # Verify path INIT->DIGEST cipher = AES.new(self.key_128, AES.MODE_EAX, nonce=self.nonce_96) cipher.digest() def test_valid_init_verify(self): # Verify path INIT->VERIFY cipher = AES.new(self.key_128, AES.MODE_EAX, nonce=self.nonce_96) mac = cipher.digest() cipher = AES.new(self.key_128, AES.MODE_EAX, nonce=self.nonce_96) cipher.verify(mac) def test_valid_multiple_encrypt_or_decrypt(self): for method_name in "encrypt", "decrypt": for auth_data in (None, b"333", self.data_128, self.data_128 + b"3"): if auth_data is None: assoc_len = None else: assoc_len = len(auth_data) cipher = AES.new(self.key_128, AES.MODE_EAX, nonce=self.nonce_96) if auth_data is not None: cipher.update(auth_data) method = getattr(cipher, method_name) method(self.data_128) method(self.data_128) method(self.data_128) method(self.data_128) def test_valid_multiple_digest_or_verify(self): # Multiple calls to digest cipher = AES.new(self.key_128, AES.MODE_EAX, nonce=self.nonce_96) cipher.update(self.data_128) first_mac = cipher.digest() for x in range(4): self.assertEqual(first_mac, cipher.digest()) # Multiple calls to verify cipher = AES.new(self.key_128, AES.MODE_EAX, nonce=self.nonce_96) cipher.update(self.data_128) for x in range(5): cipher.verify(first_mac) def test_valid_encrypt_and_digest_decrypt_and_verify(self): # encrypt_and_digest cipher = AES.new(self.key_128, AES.MODE_EAX, nonce=self.nonce_96) cipher.update(self.data_128) ct, mac = cipher.encrypt_and_digest(self.data_128) # decrypt_and_verify cipher = AES.new(self.key_128, AES.MODE_EAX, nonce=self.nonce_96) cipher.update(self.data_128) pt = cipher.decrypt_and_verify(ct, mac) self.assertEqual(self.data_128, pt) def test_invalid_mixing_encrypt_decrypt(self): # Once per method, with or without assoc. data for method1_name, method2_name in (("encrypt", "decrypt"), ("decrypt", "encrypt")): for assoc_data_present in (True, False): cipher = AES.new(self.key_128, AES.MODE_EAX, nonce=self.nonce_96) if assoc_data_present: cipher.update(self.data_128) getattr(cipher, method1_name)(self.data_128) self.assertRaises(TypeError, getattr(cipher, method2_name), self.data_128) def test_invalid_encrypt_or_update_after_digest(self): for method_name in "encrypt", "update": cipher = AES.new(self.key_128, AES.MODE_EAX, nonce=self.nonce_96) cipher.encrypt(self.data_128) cipher.digest() self.assertRaises(TypeError, getattr(cipher, method_name), self.data_128) cipher = AES.new(self.key_128, AES.MODE_EAX, nonce=self.nonce_96) cipher.encrypt_and_digest(self.data_128) def test_invalid_decrypt_or_update_after_verify(self): cipher = AES.new(self.key_128, AES.MODE_EAX, nonce=self.nonce_96) ct = cipher.encrypt(self.data_128) mac = cipher.digest() for method_name in "decrypt", "update": cipher = AES.new(self.key_128, AES.MODE_EAX, nonce=self.nonce_96) cipher.decrypt(ct) cipher.verify(mac) self.assertRaises(TypeError, getattr(cipher, method_name), self.data_128) cipher = AES.new(self.key_128, AES.MODE_EAX, nonce=self.nonce_96) cipher.decrypt_and_verify(ct, mac) self.assertRaises(TypeError, getattr(cipher, method_name), self.data_128) class TestVectorsPaper(unittest.TestCase): """Class exercising the EAX test vectors found in http://www.cs.ucdavis.edu/~rogaway/papers/eax.pdf""" test_vectors_hex = [ ( '6bfb914fd07eae6b', '', '', 'e037830e8389f27b025a2d6527e79d01', '233952dee4d5ed5f9b9c6d6ff80ff478', '62EC67F9C3A4A407FCB2A8C49031A8B3' ), ( 'fa3bfd4806eb53fa', 'f7fb', '19dd', '5c4c9331049d0bdab0277408f67967e5', '91945d3f4dcbee0bf45ef52255f095a4', 'BECAF043B0A23D843194BA972C66DEBD' ), ( '234a3463c1264ac6', '1a47cb4933', 'd851d5bae0', '3a59f238a23e39199dc9266626c40f80', '01f74ad64077f2e704c0f60ada3dd523', '70C3DB4F0D26368400A10ED05D2BFF5E' ), ( '33cce2eabff5a79d', '481c9e39b1', '632a9d131a', 'd4c168a4225d8e1ff755939974a7bede', 'd07cf6cbb7f313bdde66b727afd3c5e8', '8408DFFF3C1A2B1292DC199E46B7D617' ), ( 'aeb96eaebe2970e9', '40d0c07da5e4', '071dfe16c675', 'cb0677e536f73afe6a14b74ee49844dd', '35b6d0580005bbc12b0587124557d2c2', 'FDB6B06676EEDC5C61D74276E1F8E816' ), ( 'd4482d1ca78dce0f', '4de3b35c3fc039245bd1fb7d', '835bb4f15d743e350e728414', 'abb8644fd6ccb86947c5e10590210a4f', 'bd8e6e11475e60b268784c38c62feb22', '6EAC5C93072D8E8513F750935E46DA1B' ), ( '65d2017990d62528', '8b0a79306c9ce7ed99dae4f87f8dd61636', '02083e3979da014812f59f11d52630da30', '137327d10649b0aa6e1c181db617d7f2', '7c77d6e813bed5ac98baa417477a2e7d', '1A8C98DCD73D38393B2BF1569DEEFC19' ), ( '54b9f04e6a09189a', '1bda122bce8a8dbaf1877d962b8592dd2d56', '2ec47b2c4954a489afc7ba4897edcdae8cc3', '3b60450599bd02c96382902aef7f832a', '5fff20cafab119ca2fc73549e20f5b0d', 'DDE59B97D722156D4D9AFF2BC7559826' ), ( '899a175897561d7e', '6cf36720872b8513f6eab1a8a44438d5ef11', '0de18fd0fdd91e7af19f1d8ee8733938b1e8', 'e7f6d2231618102fdb7fe55ff1991700', 'a4a4782bcffd3ec5e7ef6d8c34a56123', 'B781FCF2F75FA5A8DE97A9CA48E522EC' ), ( '126735fcc320d25a', 'ca40d7446e545ffaed3bd12a740a659ffbbb3ceab7', 'cb8920f87a6c75cff39627b56e3ed197c552d295a7', 'cfc46afc253b4652b1af3795b124ab6e', '8395fcf1e95bebd697bd010bc766aac3', '22E7ADD93CFC6393C57EC0B3C17D6B44' ), ] test_vectors = [[unhexlify(x) for x in tv] for tv in test_vectors_hex] def runTest(self): for assoc_data, pt, ct, mac, key, nonce in self.test_vectors: # Encrypt cipher = AES.new(key, AES.MODE_EAX, nonce, mac_len=len(mac)) cipher.update(assoc_data) ct2, mac2 = cipher.encrypt_and_digest(pt) self.assertEqual(ct, ct2) self.assertEqual(mac, mac2) # Decrypt cipher = AES.new(key, AES.MODE_EAX, nonce, mac_len=len(mac)) cipher.update(assoc_data) pt2 = cipher.decrypt_and_verify(ct, mac) self.assertEqual(pt, pt2) class TestVectorsWycheproof(unittest.TestCase): def __init__(self, wycheproof_warnings): unittest.TestCase.__init__(self) self._wycheproof_warnings = wycheproof_warnings self._id = "None" def setUp(self): def filter_tag(group): return group['tagSize'] // 8 self.tv = load_test_vectors_wycheproof(("Cipher", "wycheproof"), "aes_eax_test.json", "Wycheproof EAX", group_tag={'tag_size': filter_tag}) def shortDescription(self): return self._id def warn(self, tv): if tv.warning and self._wycheproof_warnings: import warnings warnings.warn("Wycheproof warning: %s (%s)" % (self._id, tv.comment)) def test_encrypt(self, tv): self._id = "Wycheproof Encrypt EAX Test #" + str(tv.id) try: cipher = AES.new(tv.key, AES.MODE_EAX, tv.iv, mac_len=tv.tag_size) except ValueError as e: assert len(tv.iv) == 0 and "Nonce cannot be empty" in str(e) return cipher.update(tv.aad) ct, tag = cipher.encrypt_and_digest(tv.msg) if tv.valid: self.assertEqual(ct, tv.ct) self.assertEqual(tag, tv.tag) self.warn(tv) def test_decrypt(self, tv): self._id = "Wycheproof Decrypt EAX Test #" + str(tv.id) try: cipher = AES.new(tv.key, AES.MODE_EAX, tv.iv, mac_len=tv.tag_size) except ValueError as e: assert len(tv.iv) == 0 and "Nonce cannot be empty" in str(e) return cipher.update(tv.aad) try: pt = cipher.decrypt_and_verify(tv.ct, tv.tag) except ValueError: assert not tv.valid else: assert tv.valid self.assertEqual(pt, tv.msg) self.warn(tv) def test_corrupt_decrypt(self, tv): self._id = "Wycheproof Corrupt Decrypt EAX Test #" + str(tv.id) if len(tv.iv) == 0 or len(tv.ct) < 1: return cipher = AES.new(tv.key, AES.MODE_EAX, tv.iv, mac_len=tv.tag_size) cipher.update(tv.aad) ct_corrupt = strxor(tv.ct, b"\x00" * (len(tv.ct) - 1) + b"\x01") self.assertRaises(ValueError, cipher.decrypt_and_verify, ct_corrupt, tv.tag) def runTest(self): for tv in self.tv: self.test_encrypt(tv) self.test_decrypt(tv) self.test_corrupt_decrypt(tv) class TestOtherCiphers(unittest.TestCase): @classmethod def create_test(cls, name, factory, key_size): def test_template(self, factory=factory, key_size=key_size): cipher = factory.new(get_tag_random("cipher", key_size), factory.MODE_EAX, nonce=b"nonce") ct, mac = cipher.encrypt_and_digest(b"plaintext") cipher = factory.new(get_tag_random("cipher", key_size), factory.MODE_EAX, nonce=b"nonce") pt2 = cipher.decrypt_and_verify(ct, mac) self.assertEqual(b"plaintext", pt2) setattr(cls, "test_" + name, test_template) from Crypto.Cipher import DES, DES3, ARC2, CAST, Blowfish TestOtherCiphers.create_test("DES_" + str(DES.key_size), DES, DES.key_size) for ks in DES3.key_size: TestOtherCiphers.create_test("DES3_" + str(ks), DES3, ks) for ks in ARC2.key_size: TestOtherCiphers.create_test("ARC2_" + str(ks), ARC2, ks) for ks in CAST.key_size: TestOtherCiphers.create_test("CAST_" + str(ks), CAST, ks) for ks in Blowfish.key_size: TestOtherCiphers.create_test("Blowfish_" + str(ks), Blowfish, ks) def get_tests(config={}): wycheproof_warnings = config.get('wycheproof_warnings') tests = [] tests += list_test_cases(EaxTests) tests += list_test_cases(EaxFSMTests) tests += [ TestVectorsPaper() ] tests += [ TestVectorsWycheproof(wycheproof_warnings) ] tests += list_test_cases(TestOtherCiphers) return tests if __name__ == '__main__': suite = lambda: unittest.TestSuite(get_tests()) unittest.main(defaultTest='suite')