blob: a82df41df4a528a9da28012fdd1f12d56034774d [file] [log] [blame]
Gilles Peskinefdb72232023-06-19 20:46:47 +02001"""Collect information about PSA cryptographic mechanisms.
2"""
3
4# Copyright The Mbed TLS Contributors
5# SPDX-License-Identifier: Apache-2.0
6#
7# Licensed under the Apache License, Version 2.0 (the "License"); you may
8# not use this file except in compliance with the License.
9# You may obtain a copy of the License at
10#
11# http://www.apache.org/licenses/LICENSE-2.0
12#
13# Unless required by applicable law or agreed to in writing, software
14# distributed under the License is distributed on an "AS IS" BASIS, WITHOUT
15# WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
16# See the License for the specific language governing permissions and
17# limitations under the License.
18
19import re
20from typing import Dict, FrozenSet, List, Optional
21
22from . import macro_collector
23
24
25class Information:
26 """Gather information about PSA constructors."""
27
28 def __init__(self) -> None:
29 self.constructors = self.read_psa_interface()
30
31 @staticmethod
32 def remove_unwanted_macros(
33 constructors: macro_collector.PSAMacroEnumerator
34 ) -> None:
35 # Mbed TLS does not support finite-field DSA.
36 # Don't attempt to generate any related test case.
37 constructors.key_types.discard('PSA_KEY_TYPE_DSA_KEY_PAIR')
38 constructors.key_types.discard('PSA_KEY_TYPE_DSA_PUBLIC_KEY')
39
40 def read_psa_interface(self) -> macro_collector.PSAMacroEnumerator:
41 """Return the list of known key types, algorithms, etc."""
42 constructors = macro_collector.InputsForTest()
43 header_file_names = ['include/psa/crypto_values.h',
44 'include/psa/crypto_extra.h']
45 test_suites = ['tests/suites/test_suite_psa_crypto_metadata.data']
46 for header_file_name in header_file_names:
47 constructors.parse_header(header_file_name)
48 for test_cases in test_suites:
49 constructors.parse_test_cases(test_cases)
50 self.remove_unwanted_macros(constructors)
51 constructors.gather_arguments()
52 return constructors
53
54
55def psa_want_symbol(name: str) -> str:
56 """Return the PSA_WANT_xxx symbol associated with a PSA crypto feature."""
57 if name.startswith('PSA_'):
58 return name[:4] + 'WANT_' + name[4:]
59 else:
60 raise ValueError('Unable to determine the PSA_WANT_ symbol for ' + name)
61
62def finish_family_dependency(dep: str, bits: int) -> str:
63 """Finish dep if it's a family dependency symbol prefix.
64
65 A family dependency symbol prefix is a PSA_WANT_ symbol that needs to be
66 qualified by the key size. If dep is such a symbol, finish it by adjusting
67 the prefix and appending the key size. Other symbols are left unchanged.
68 """
69 return re.sub(r'_FAMILY_(.*)', r'_\1_' + str(bits), dep)
70
71def finish_family_dependencies(dependencies: List[str], bits: int) -> List[str]:
72 """Finish any family dependency symbol prefixes.
73
74 Apply `finish_family_dependency` to each element of `dependencies`.
75 """
76 return [finish_family_dependency(dep, bits) for dep in dependencies]
77
78SYMBOLS_WITHOUT_DEPENDENCY = frozenset([
79 'PSA_ALG_AEAD_WITH_AT_LEAST_THIS_LENGTH_TAG', # modifier, only in policies
80 'PSA_ALG_AEAD_WITH_SHORTENED_TAG', # modifier
81 'PSA_ALG_ANY_HASH', # only in policies
82 'PSA_ALG_AT_LEAST_THIS_LENGTH_MAC', # modifier, only in policies
83 'PSA_ALG_KEY_AGREEMENT', # chaining
84 'PSA_ALG_TRUNCATED_MAC', # modifier
85])
86def automatic_dependencies(*expressions: str) -> List[str]:
87 """Infer dependencies of a test case by looking for PSA_xxx symbols.
88
89 The arguments are strings which should be C expressions. Do not use
90 string literals or comments as this function is not smart enough to
91 skip them.
92 """
93 used = set()
94 for expr in expressions:
95 used.update(re.findall(r'PSA_(?:ALG|ECC_FAMILY|KEY_TYPE)_\w+', expr))
96 used.difference_update(SYMBOLS_WITHOUT_DEPENDENCY)
97 return sorted(psa_want_symbol(name) for name in used)
98
99# Define set of regular expressions and dependencies to optionally append
100# extra dependencies for test case.
101AES_128BIT_ONLY_DEP_REGEX = r'AES\s(192|256)'
102AES_128BIT_ONLY_DEP = ["!MBEDTLS_AES_ONLY_128_BIT_KEY_LENGTH"]
103
104DEPENDENCY_FROM_KEY = {
105 AES_128BIT_ONLY_DEP_REGEX: AES_128BIT_ONLY_DEP
106}#type: Dict[str, List[str]]
107def generate_key_dependencies(description: str) -> List[str]:
108 """Return additional dependencies based on pairs of REGEX and dependencies.
109 """
110 deps = []
111 for regex, dep in DEPENDENCY_FROM_KEY.items():
112 if re.search(regex, description):
113 deps += dep
114
115 return deps
116
117# A temporary hack: at the time of writing, not all dependency symbols
118# are implemented yet. Skip test cases for which the dependency symbols are
119# not available. Once all dependency symbols are available, this hack must
120# be removed so that a bug in the dependency symbols properly leads to a test
121# failure.
122def read_implemented_dependencies(filename: str) -> FrozenSet[str]:
123 return frozenset(symbol
124 for line in open(filename)
125 for symbol in re.findall(r'\bPSA_WANT_\w+\b', line))
126_implemented_dependencies = None #type: Optional[FrozenSet[str]] #pylint: disable=invalid-name
127def hack_dependencies_not_implemented(dependencies: List[str]) -> None:
128 global _implemented_dependencies #pylint: disable=global-statement,invalid-name
129 if _implemented_dependencies is None:
130 _implemented_dependencies = \
131 read_implemented_dependencies('include/psa/crypto_config.h')
132 if not all((dep.lstrip('!') in _implemented_dependencies or
133 not dep.lstrip('!').startswith('PSA_WANT'))
134 for dep in dependencies):
135 dependencies.append('DEPENDENCY_NOT_IMPLEMENTED_YET')
136
137def tweak_key_pair_dependency(dep: str, usage: str):
138 """
139 This helper function add the proper suffix to PSA_WANT_KEY_TYPE_xxx_KEY_PAIR
140 symbols according to the required usage.
141 """
142 ret_list = list()
143 if dep.endswith('KEY_PAIR'):
144 if usage == "BASIC":
145 # BASIC automatically includes IMPORT and EXPORT for test purposes (see
146 # config_psa.h).
147 ret_list.append(re.sub(r'KEY_PAIR', r'KEY_PAIR_BASIC', dep))
148 ret_list.append(re.sub(r'KEY_PAIR', r'KEY_PAIR_IMPORT', dep))
149 ret_list.append(re.sub(r'KEY_PAIR', r'KEY_PAIR_EXPORT', dep))
150 elif usage == "GENERATE":
151 ret_list.append(re.sub(r'KEY_PAIR', r'KEY_PAIR_GENERATE', dep))
152 else:
153 # No replacement to do in this case
154 ret_list.append(dep)
155 return ret_list
156
157def fix_key_pair_dependencies(dep_list: List[str], usage: str):
158 new_list = [new_deps
159 for dep in dep_list
160 for new_deps in tweak_key_pair_dependency(dep, usage)]
161
162 return new_list