# SPDX-FileCopyrightText: 2016 Legrandin # SPDX-License-Identifier: BSD-2-Clause import binascii import errno import json import os import re import warnings from binascii import unhexlify try: import pycryptodome_test_vectors # type: ignore test_vectors_available = True except ImportError: test_vectors_available = False def warn_skipped_tests(message, stacklevel=2): """Warn that some extended tests are skipped, because a file of test vectors is missing from the package pycryptodome-test-vectors. If the whole package is not installed, nothing is reported here: the plugin of the self-tests says it once, at the start and at the end of the run (instead of a warning for each file). ``stacklevel`` is the one of the caller of this function.""" if test_vectors_available: warnings.warn(message, UserWarning, stacklevel=stacklevel + 1) def _load_tests(dir_comps, file_in, description, conversions): """Load and parse a test vector file Return a list of objects, one per group of adjacent KV lines or for a single line in the form "[.*]". For a group of lines, the object has one attribute per line. """ line_number = 0 results = [] class TestVector: def __init__(self, description, count): self.desc = description self.count = count self.others = [] test_vector = None count = 0 new_group = True while True: line_number += 1 line = file_in.readline() if not line: if test_vector is not None: results.append(test_vector) break line = line.strip() # Skip comments and empty lines if line.startswith("#") or not line: new_group = True continue if line.startswith("["): if test_vector is not None: results.append(test_vector) test_vector = None results.append(line) continue if new_group: count += 1 new_group = False if test_vector is not None: results.append(test_vector) test_vector = TestVector("%s (#%d)" % (description, count), count) res = re.match("([A-Za-z0-9]+) = ?(.*)", line) if not res: test_vector.others += [line] else: token = res.group(1).lower() data = res.group(2).lower() conversion = conversions.get(token, None) if conversion is None: if len(data) % 2 != 0: data = "0" + data setattr(test_vector, token, binascii.unhexlify(data)) else: setattr(test_vector, token, conversion(data)) # This line is ignored return results def load_test_vectors(dir_comps, file_name, description, conversions): """Load and parse a test vector file, formatted using the NIST style. Args: dir_comps (list of strings): The path components under the ``pycryptodome_test_vectors`` package. For instance ``("Cipher", "AES")``. file_name (string): The name of the file with the test vectors. description (string): A description applicable to the test vectors in the file. conversions (dictionary): The dictionary contains functions. Values in the file that have an entry in this dictionary will be converted usign the matching function. Otherwise, values will be considered as hexadecimal and converted to binary. Returns: A list of test vector objects. The file is formatted in the following way: - Lines starting with "#" are comments and will be ignored. - Each test vector is a sequence of 1 or more adjacent lines, where each lines is an assignement. - Test vectors are separated by an empty line, a comment, or a line starting with "[". A test vector object has the following attributes: - desc (string): description - counter (int): the order of the test vector in the file (from 1) - others (list): zero or more lines of the test vector that were not assignments - left-hand side of each assignment (lowercase): the value of the assignement, either converted or bytes. """ results = None try: if not test_vectors_available: raise FileNotFoundError(errno.ENOENT, os.strerror(errno.ENOENT), file_name) description = "%s test (%s)" % (description, file_name) init_dir = os.path.dirname(pycryptodome_test_vectors.__file__) full_file_name = os.path.join(os.path.join(init_dir, *dir_comps), file_name) with open(full_file_name) as file_in: results = _load_tests(dir_comps, file_in, description, conversions) except FileNotFoundError: warn_skipped_tests("Warning: skipping extended tests for " + description) return results def load_test_vectors_wycheproof(dir_comps, file_name, description, root_tag={}, group_tag={}, unit_tag={}): result = [] try: if not test_vectors_available: raise FileNotFoundError(errno.ENOENT, os.strerror(errno.ENOENT), file_name) init_dir = os.path.dirname(pycryptodome_test_vectors.__file__) full_file_name = os.path.join(os.path.join(init_dir, *dir_comps), file_name) with open(full_file_name) as file_in: tv_tree = json.load(file_in) except FileNotFoundError: warn_skipped_tests("Warning: skipping extended tests for " + description) return result class TestVector: pass # Unique attributes that will be converted from # hexadecimal to binary, unless the attribute is # listed in the unit_tag dict unit_attr_hex = { "key", "iv", "aad", "msg", "ct", "tag", "label", "ikm", "salt", "info", "okm", "sig", "public", "shared", } unit_attr_hex -= set(unit_tag.keys()) common_root = {} for k, v in root_tag.items(): common_root[k] = v(tv_tree) for group in tv_tree["testGroups"]: common_group = {} for k, v in group_tag.items(): common_group[k] = v(group) for test in group["tests"]: tv = TestVector() for k, v in common_root.items(): setattr(tv, k, v) for k, v in common_group.items(): setattr(tv, k, v) tv.id = test["tcId"] tv.comment = test.get("comment", "") for attr in unit_attr_hex: if attr in test: try: setattr(tv, attr, unhexlify(test[attr])) except binascii.Error: raise ValueError( "Error decoding attribute '%s' (tcId=%s, file %s)" % (attr, tv.id, file_name) ) tv.filename = file_name for k, v in unit_tag.items(): setattr(tv, k, v(test)) tv.valid = test["result"] != "invalid" tv.warning = test["result"] == "acceptable" tv.flags = test.get("flags") tv.filename = file_name result.append(tv) return result def wycheproof_id(tv): """Return the pytest ID of a Wycheproof test vector (e.g. 'aes_gcm-12')""" name = tv.filename if name.endswith("_test.json"): name = name[: -len("_test.json")] return "%s-%d" % (name, tv.id)