| #!/usr/bin/env python3 |
| """Generate test data for PSA cryptographic mechanisms. |
| |
| With no arguments, generate all test data. With non-option arguments, |
| generate only the specified files. |
| """ |
| |
| # Copyright The Mbed TLS Contributors |
| # SPDX-License-Identifier: Apache-2.0 |
| # |
| # Licensed under the Apache License, Version 2.0 (the "License"); you may |
| # not use this file except in compliance with the License. |
| # You may obtain a copy of the License at |
| # |
| # http://www.apache.org/licenses/LICENSE-2.0 |
| # |
| # Unless required by applicable law or agreed to in writing, software |
| # distributed under the License is distributed on an "AS IS" BASIS, WITHOUT |
| # WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. |
| # See the License for the specific language governing permissions and |
| # limitations under the License. |
| |
| import argparse |
| import os |
| import re |
| import sys |
| from typing import Callable, Dict, FrozenSet, Iterable, Iterator, List, Optional, TypeVar |
| |
| import scripts_path # pylint: disable=unused-import |
| from mbedtls_dev import crypto_knowledge |
| from mbedtls_dev import macro_collector |
| from mbedtls_dev import psa_storage |
| from mbedtls_dev import test_case |
| |
| T = TypeVar('T') #pylint: disable=invalid-name |
| |
| |
| def psa_want_symbol(name: str) -> str: |
| """Return the PSA_WANT_xxx symbol associated with a PSA crypto feature.""" |
| if name.startswith('PSA_'): |
| return name[:4] + 'WANT_' + name[4:] |
| else: |
| raise ValueError('Unable to determine the PSA_WANT_ symbol for ' + name) |
| |
| def finish_family_dependency(dep: str, bits: int) -> str: |
| """Finish dep if it's a family dependency symbol prefix. |
| |
| A family dependency symbol prefix is a PSA_WANT_ symbol that needs to be |
| qualified by the key size. If dep is such a symbol, finish it by adjusting |
| the prefix and appending the key size. Other symbols are left unchanged. |
| """ |
| return re.sub(r'_FAMILY_(.*)', r'_\1_' + str(bits), dep) |
| |
| def finish_family_dependencies(dependencies: List[str], bits: int) -> List[str]: |
| """Finish any family dependency symbol prefixes. |
| |
| Apply `finish_family_dependency` to each element of `dependencies`. |
| """ |
| return [finish_family_dependency(dep, bits) for dep in dependencies] |
| |
| def automatic_dependencies(*expressions: str) -> List[str]: |
| """Infer dependencies of a test case by looking for PSA_xxx symbols. |
| |
| The arguments are strings which should be C expressions. Do not use |
| string literals or comments as this function is not smart enough to |
| skip them. |
| """ |
| used = set() |
| for expr in expressions: |
| used.update(re.findall(r'PSA_(?:ALG|ECC_FAMILY|KEY_TYPE)_\w+', expr)) |
| return sorted(psa_want_symbol(name) for name in used) |
| |
| # A temporary hack: at the time of writing, not all dependency symbols |
| # are implemented yet. Skip test cases for which the dependency symbols are |
| # not available. Once all dependency symbols are available, this hack must |
| # be removed so that a bug in the dependency symbols proprely leads to a test |
| # failure. |
| def read_implemented_dependencies(filename: str) -> FrozenSet[str]: |
| return frozenset(symbol |
| for line in open(filename) |
| for symbol in re.findall(r'\bPSA_WANT_\w+\b', line)) |
| IMPLEMENTED_DEPENDENCIES = read_implemented_dependencies('include/psa/crypto_config.h') |
| def hack_dependencies_not_implemented(dependencies: List[str]) -> None: |
| if not all(dep.lstrip('!') in IMPLEMENTED_DEPENDENCIES |
| for dep in dependencies): |
| dependencies.append('DEPENDENCY_NOT_IMPLEMENTED_YET') |
| |
| |
| class Information: |
| """Gather information about PSA constructors.""" |
| |
| def __init__(self) -> None: |
| self.constructors = self.read_psa_interface() |
| |
| @staticmethod |
| def remove_unwanted_macros( |
| constructors: macro_collector.PSAMacroCollector |
| ) -> None: |
| # Mbed TLS doesn't support DSA. Don't attempt to generate any related |
| # test case. |
| constructors.key_types.discard('PSA_KEY_TYPE_DSA_KEY_PAIR') |
| constructors.key_types.discard('PSA_KEY_TYPE_DSA_PUBLIC_KEY') |
| constructors.algorithms_from_hash.pop('PSA_ALG_DSA', None) |
| constructors.algorithms_from_hash.pop('PSA_ALG_DETERMINISTIC_DSA', None) |
| |
| def read_psa_interface(self) -> macro_collector.PSAMacroCollector: |
| """Return the list of known key types, algorithms, etc.""" |
| constructors = macro_collector.PSAMacroCollector() |
| header_file_names = ['include/psa/crypto_values.h', |
| 'include/psa/crypto_extra.h'] |
| for header_file_name in header_file_names: |
| with open(header_file_name, 'rb') as header_file: |
| constructors.read_file(header_file) |
| self.remove_unwanted_macros(constructors) |
| return constructors |
| |
| |
| def test_case_for_key_type_not_supported( |
| verb: str, key_type: str, bits: int, |
| dependencies: List[str], |
| *args: str, |
| param_descr: str = '' |
| ) -> test_case.TestCase: |
| """Return one test case exercising a key creation method |
| for an unsupported key type or size. |
| """ |
| hack_dependencies_not_implemented(dependencies) |
| tc = test_case.TestCase() |
| short_key_type = re.sub(r'PSA_(KEY_TYPE|ECC_FAMILY)_', r'', key_type) |
| adverb = 'not' if dependencies else 'never' |
| if param_descr: |
| adverb = param_descr + ' ' + adverb |
| tc.set_description('PSA {} {} {}-bit {} supported' |
| .format(verb, short_key_type, bits, adverb)) |
| tc.set_dependencies(dependencies) |
| tc.set_function(verb + '_not_supported') |
| tc.set_arguments([key_type] + list(args)) |
| return tc |
| |
| class NotSupported: |
| """Generate test cases for when something is not supported.""" |
| |
| def __init__(self, info: Information) -> None: |
| self.constructors = info.constructors |
| |
| ALWAYS_SUPPORTED = frozenset([ |
| 'PSA_KEY_TYPE_DERIVE', |
| 'PSA_KEY_TYPE_RAW_DATA', |
| ]) |
| def test_cases_for_key_type_not_supported( |
| self, |
| kt: crypto_knowledge.KeyType, |
| param: Optional[int] = None, |
| param_descr: str = '', |
| ) -> Iterator[test_case.TestCase]: |
| """Return test cases exercising key creation when the given type is unsupported. |
| |
| If param is present and not None, emit test cases conditioned on this |
| parameter not being supported. If it is absent or None, emit test cases |
| conditioned on the base type not being supported. |
| """ |
| if kt.name in self.ALWAYS_SUPPORTED: |
| # Don't generate test cases for key types that are always supported. |
| # They would be skipped in all configurations, which is noise. |
| return |
| import_dependencies = [('!' if param is None else '') + |
| psa_want_symbol(kt.name)] |
| if kt.params is not None: |
| import_dependencies += [('!' if param == i else '') + |
| psa_want_symbol(sym) |
| for i, sym in enumerate(kt.params)] |
| if kt.name.endswith('_PUBLIC_KEY'): |
| generate_dependencies = [] |
| else: |
| generate_dependencies = import_dependencies |
| for bits in kt.sizes_to_test(): |
| yield test_case_for_key_type_not_supported( |
| 'import', kt.expression, bits, |
| finish_family_dependencies(import_dependencies, bits), |
| test_case.hex_string(kt.key_material(bits)), |
| param_descr=param_descr, |
| ) |
| if not generate_dependencies and param is not None: |
| # If generation is impossible for this key type, rather than |
| # supported or not depending on implementation capabilities, |
| # only generate the test case once. |
| continue |
| yield test_case_for_key_type_not_supported( |
| 'generate', kt.expression, bits, |
| finish_family_dependencies(generate_dependencies, bits), |
| str(bits), |
| param_descr=param_descr, |
| ) |
| # To be added: derive |
| |
| def test_cases_for_not_supported(self) -> Iterator[test_case.TestCase]: |
| """Generate test cases that exercise the creation of keys of unsupported types.""" |
| for key_type in sorted(self.constructors.key_types): |
| kt = crypto_knowledge.KeyType(key_type) |
| yield from self.test_cases_for_key_type_not_supported(kt) |
| for curve_family in sorted(self.constructors.ecc_curves): |
| for constr in ('PSA_KEY_TYPE_ECC_KEY_PAIR', |
| 'PSA_KEY_TYPE_ECC_PUBLIC_KEY'): |
| kt = crypto_knowledge.KeyType(constr, [curve_family]) |
| yield from self.test_cases_for_key_type_not_supported( |
| kt, param_descr='type') |
| yield from self.test_cases_for_key_type_not_supported( |
| kt, 0, param_descr='curve') |
| |
| |
| class StorageKey(psa_storage.Key): |
| """Representation of a key for storage format testing.""" |
| |
| def __init__(self, *, description: str, **kwargs) -> None: |
| super().__init__(**kwargs) |
| self.description = description #type: str |
| |
| class StorageFormat: |
| """Storage format stability test cases.""" |
| |
| def __init__(self, info: Information, version: int, forward: bool) -> None: |
| """Prepare to generate test cases for storage format stability. |
| |
| * `info`: information about the API. See the `Information` class. |
| * `version`: the storage format version to generate test cases for. |
| * `forward`: if true, generate forward compatibility test cases which |
| save a key and check that its representation is as intended. Otherwise |
| generate backward compatibility test cases which inject a key |
| representation and check that it can be read and used. |
| """ |
| self.constructors = info.constructors |
| self.version = version |
| self.forward = forward |
| |
| def make_test_case(self, key: StorageKey) -> test_case.TestCase: |
| """Construct a storage format test case for the given key. |
| |
| If ``forward`` is true, generate a forward compatibility test case: |
| create a key and validate that it has the expected representation. |
| Otherwise generate a backward compatibility test case: inject the |
| key representation into storage and validate that it can be read |
| correctly. |
| """ |
| verb = 'save' if self.forward else 'read' |
| tc = test_case.TestCase() |
| tc.set_description('PSA storage {}: {}'.format(verb, key.description)) |
| dependencies = automatic_dependencies( |
| key.lifetime.string, key.type.string, |
| key.usage.string, key.alg.string, key.alg2.string, |
| ) |
| dependencies = finish_family_dependencies(dependencies, key.bits) |
| tc.set_dependencies(dependencies) |
| tc.set_function('key_storage_' + verb) |
| if self.forward: |
| extra_arguments = [] |
| else: |
| # Some test keys have the RAW_DATA type and attributes that don't |
| # necessarily make sense. We do this to validate numerical |
| # encodings of the attributes. |
| # Raw data keys have no useful exercise anyway so there is no |
| # loss of test coverage. |
| exercise = key.type.string != 'PSA_KEY_TYPE_RAW_DATA' |
| extra_arguments = ['1' if exercise else '0'] |
| tc.set_arguments([key.lifetime.string, |
| key.type.string, str(key.bits), |
| key.usage.string, key.alg.string, key.alg2.string, |
| '"' + key.material.hex() + '"', |
| '"' + key.hex() + '"', |
| *extra_arguments]) |
| return tc |
| |
| def key_for_usage_flags( |
| self, |
| usage_flags: List[str], |
| short: Optional[str] = None |
| ) -> StorageKey: |
| """Construct a test key for the given key usage.""" |
| usage = ' | '.join(usage_flags) if usage_flags else '0' |
| if short is None: |
| short = re.sub(r'\bPSA_KEY_USAGE_', r'', usage) |
| description = 'usage: ' + short |
| key = StorageKey(version=self.version, |
| id=1, lifetime=0x00000001, |
| type='PSA_KEY_TYPE_RAW_DATA', bits=8, |
| usage=usage, alg=0, alg2=0, |
| material=b'K', |
| description=description) |
| return key |
| |
| def all_keys_for_usage_flags(self) -> Iterator[StorageKey]: |
| """Generate test keys covering usage flags.""" |
| known_flags = sorted(self.constructors.key_usage_flags) |
| yield self.key_for_usage_flags(['0']) |
| for usage_flag in known_flags: |
| yield self.key_for_usage_flags([usage_flag]) |
| for flag1, flag2 in zip(known_flags, |
| known_flags[1:] + [known_flags[0]]): |
| yield self.key_for_usage_flags([flag1, flag2]) |
| yield self.key_for_usage_flags(known_flags, short='all known') |
| |
| def keys_for_type( |
| self, |
| key_type: str, |
| params: Optional[Iterable[str]] = None |
| ) -> Iterator[StorageKey]: |
| """Generate test keys for the given key type. |
| |
| For key types that depend on a parameter (e.g. elliptic curve family), |
| `param` is the parameter to pass to the constructor. Only a single |
| parameter is supported. |
| """ |
| kt = crypto_knowledge.KeyType(key_type, params) |
| for bits in kt.sizes_to_test(): |
| usage_flags = 'PSA_KEY_USAGE_EXPORT' |
| alg = 0 |
| alg2 = 0 |
| key_material = kt.key_material(bits) |
| short_expression = re.sub(r'\bPSA_(?:KEY_TYPE|ECC_FAMILY)_', |
| r'', |
| kt.expression) |
| description = 'type: {} {}-bit'.format(short_expression, bits) |
| key = StorageKey(version=self.version, |
| id=1, lifetime=0x00000001, |
| type=kt.expression, bits=bits, |
| usage=usage_flags, alg=alg, alg2=alg2, |
| material=key_material, |
| description=description) |
| yield key |
| |
| def all_keys_for_types(self) -> Iterator[StorageKey]: |
| """Generate test keys covering key types and their representations.""" |
| for key_type in sorted(self.constructors.key_types): |
| yield from self.keys_for_type(key_type) |
| for key_type in sorted(self.constructors.key_types_from_curve): |
| for curve in sorted(self.constructors.ecc_curves): |
| yield from self.keys_for_type(key_type, [curve]) |
| ## Diffie-Hellman (FFDH) is not supported yet, either in |
| ## crypto_knowledge.py or in Mbed TLS. |
| # for key_type in sorted(self.constructors.key_types_from_group): |
| # for group in sorted(self.constructors.dh_groups): |
| # yield from self.keys_for_type(key_type, [group]) |
| |
| def keys_for_algorithm(self, alg: str) -> Iterator[StorageKey]: |
| """Generate test keys for the specified algorithm.""" |
| # For now, we don't have information on the compatibility of key |
| # types and algorithms. So we just test the encoding of algorithms, |
| # and not that operations can be performed with them. |
| descr = alg |
| usage = 'PSA_KEY_USAGE_EXPORT' |
| key1 = StorageKey(version=self.version, |
| id=1, lifetime=0x00000001, |
| type='PSA_KEY_TYPE_RAW_DATA', bits=8, |
| usage=usage, alg=alg, alg2=0, |
| material=b'K', |
| description='alg: ' + descr) |
| yield key1 |
| key2 = StorageKey(version=self.version, |
| id=1, lifetime=0x00000001, |
| type='PSA_KEY_TYPE_RAW_DATA', bits=8, |
| usage=usage, alg=0, alg2=alg, |
| material=b'L', |
| description='alg2: ' + descr) |
| yield key2 |
| |
| def all_keys_for_algorithms(self) -> Iterator[StorageKey]: |
| """Generate test keys covering algorithm encodings.""" |
| for alg in sorted(self.constructors.algorithms): |
| yield from self.keys_for_algorithm(alg) |
| # To do: algorithm constructors with parameters |
| |
| def all_test_cases(self) -> Iterator[test_case.TestCase]: |
| """Generate all storage format test cases.""" |
| for key in self.all_keys_for_usage_flags(): |
| yield self.make_test_case(key) |
| for key in self.all_keys_for_types(): |
| yield self.make_test_case(key) |
| for key in self.all_keys_for_algorithms(): |
| yield self.make_test_case(key) |
| # To do: vary id, lifetime |
| |
| |
| class TestGenerator: |
| """Generate test data.""" |
| |
| def __init__(self, options) -> None: |
| self.test_suite_directory = self.get_option(options, 'directory', |
| 'tests/suites') |
| self.info = Information() |
| |
| @staticmethod |
| def get_option(options, name: str, default: T) -> T: |
| value = getattr(options, name, None) |
| return default if value is None else value |
| |
| def filename_for(self, basename: str) -> str: |
| """The location of the data file with the specified base name.""" |
| return os.path.join(self.test_suite_directory, basename + '.data') |
| |
| def write_test_data_file(self, basename: str, |
| test_cases: Iterable[test_case.TestCase]) -> None: |
| """Write the test cases to a .data file. |
| |
| The output file is ``basename + '.data'`` in the test suite directory. |
| """ |
| filename = self.filename_for(basename) |
| test_case.write_data_file(filename, test_cases) |
| |
| TARGETS = { |
| 'test_suite_psa_crypto_not_supported.generated': |
| lambda info: NotSupported(info).test_cases_for_not_supported(), |
| 'test_suite_psa_crypto_storage_format.current': |
| lambda info: StorageFormat(info, 0, True).all_test_cases(), |
| 'test_suite_psa_crypto_storage_format.v0': |
| lambda info: StorageFormat(info, 0, False).all_test_cases(), |
| } #type: Dict[str, Callable[[Information], Iterable[test_case.TestCase]]] |
| |
| def generate_target(self, name: str) -> None: |
| test_cases = self.TARGETS[name](self.info) |
| self.write_test_data_file(name, test_cases) |
| |
| def main(args): |
| """Command line entry point.""" |
| parser = argparse.ArgumentParser(description=__doc__) |
| parser.add_argument('--list', action='store_true', |
| help='List available targets and exit') |
| parser.add_argument('targets', nargs='*', metavar='TARGET', |
| help='Target file to generate (default: all; "-": none)') |
| options = parser.parse_args(args) |
| generator = TestGenerator(options) |
| if options.list: |
| for name in sorted(generator.TARGETS): |
| print(generator.filename_for(name)) |
| return |
| if options.targets: |
| # Allow "-" as a special case so you can run |
| # ``generate_psa_tests.py - $targets`` and it works uniformly whether |
| # ``$targets`` is empty or not. |
| options.targets = [os.path.basename(re.sub(r'\.data\Z', r'', target)) |
| for target in options.targets |
| if target != '-'] |
| else: |
| options.targets = sorted(generator.TARGETS) |
| for target in options.targets: |
| generator.generate_target(target) |
| |
| if __name__ == '__main__': |
| main(sys.argv[1:]) |
