tests/primitives/test_nist.py

# Licensed under the Apache License, Version 2.0 (the "License");
# you may not use this file except in compliance with the License.
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#
#    http://www.apache.org/licenses/LICENSE-2.0
#
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"""
Test using the NIST Test Vectors
"""

from __future__ import absolute_import, division, print_function

import binascii
import itertools
import os

import pytest

from cryptography.primitives.block import BlockCipher, ciphers, modes

from ..utils import load_nist_vectors_from_file


def parameterize_encrypt_test(cipher, vector_type, fnames):
    return pytest.mark.parametrize(("key", "iv", "plaintext", "ciphertext"),
        list(itertools.chain.from_iterable(
            load_nist_vectors_from_file(
                os.path.join(cipher, vector_type, fname),
                "ENCRYPT",
                ["key", "iv", "plaintext", "ciphertext"],
            )
            for fname in fnames
        ))
    )


class TestAES_CBC(object):
    @parameterize_encrypt_test("AES", "KAT", [
        "CBCGFSbox128.rsp",
        "CBCGFSbox192.rsp",
        "CBCGFSbox256.rsp",
        "CBCKeySbox128.rsp",
        "CBCKeySbox192.rsp",
        "CBCKeySbox256.rsp",
        "CBCVarKey128.rsp",
        "CBCVarKey192.rsp",
        "CBCVarKey256.rsp",
        "CBCVarTxt128.rsp",
        "CBCVarTxt192.rsp",
        "CBCVarTxt256.rsp",
    ])
    def test_KAT(self, key, iv, plaintext, ciphertext):
        cipher = BlockCipher(
            ciphers.AES(binascii.unhexlify(key)),
            modes.CBC(binascii.unhexlify(iv)),
        )
        actual_ciphertext = cipher.encrypt(binascii.unhexlify(plaintext))
        actual_ciphertext += cipher.finalize()
        assert binascii.hexlify(actual_ciphertext) == ciphertext

    @parameterize_encrypt_test("AES", "MMT", [
        "CBCMMT128.rsp",
        "CBCMMT192.rsp",
        "CBCMMT256.rsp",
    ])
    def test_MMT(self, key, iv, plaintext, ciphertext):
        cipher = BlockCipher(
            ciphers.AES(binascii.unhexlify(key)),
            modes.CBC(binascii.unhexlify(iv)),
        )
        actual_ciphertext = cipher.encrypt(binascii.unhexlify(plaintext))
        actual_ciphertext += cipher.finalize()
        assert binascii.hexlify(actual_ciphertext) == ciphertext