mbedtls/tests/scripts/generate_psa_tests.py
Gilles Peskine 60b29fea46 Define WANT symbols for always-supported key types
PSA_KEY_TYPE_RAW_DATA and PSA_KEY_TYPE_DERIVE are always supported.
Make this explicit by declaring PSA_WANT_KEY_TYPE_RAW_DATA and
PSA_WANT_KEY_TYPE_DERIVE unconditionally. This makes it easier to
infer dependencies in a systematic way.

Don't generate not-supported test cases for those key types. They
would always be skipped, which is noise and would make it impossible
to eventually validate that all test cases pass in at least one
configuration over the whole CI.

Don't remove the exception in set_psa_test_dependencies.py for now, to
get less noise in dependencies. This may be revised later if it is
deemed more important to be systematic.

Signed-off-by: Gilles Peskine <Gilles.Peskine@arm.com>
2021-02-17 14:50:52 +01:00

205 lines
8.3 KiB
Python
Executable File

#!/usr/bin/env python3
"""Generate test data for PSA cryptographic mechanisms.
"""
# 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 Iterable, 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 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 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.
"""
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 TestGenerator:
"""Gather information and generate test data."""
def __init__(self, options):
self.test_suite_directory = self.get_option(options, 'directory',
'tests/suites')
self.constructors = self.read_psa_interface()
@staticmethod
def get_option(options, name: str, default: T) -> T:
value = getattr(options, name, None)
return default if value is None else value
@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 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 = os.path.join(self.test_suite_directory, basename + '.data')
test_case.write_data_file(filename, test_cases)
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 = '',
) -> List[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
test_cases = []
for bits in kt.sizes_to_test():
test_cases.append(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
test_cases.append(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
return test_cases
def generate_not_supported(self) -> None:
"""Generate test cases that exercise the creation of keys of unsupported types."""
test_cases = []
for key_type in sorted(self.constructors.key_types):
kt = crypto_knowledge.KeyType(key_type)
test_cases += self.test_cases_for_key_type_not_supported(kt)
# To be added: parametrized key types FFDH
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])
test_cases += self.test_cases_for_key_type_not_supported(
kt, param_descr='type')
test_cases += self.test_cases_for_key_type_not_supported(
kt, 0, param_descr='curve')
self.write_test_data_file(
'test_suite_psa_crypto_not_supported.generated',
test_cases)
def generate_all(self):
self.generate_not_supported()
def main(args):
"""Command line entry point."""
parser = argparse.ArgumentParser(description=__doc__)
options = parser.parse_args(args)
generator = TestGenerator(options)
generator.generate_all()
if __name__ == '__main__':
main(sys.argv[1:])