| #!/usr/bin/env python3 |
| |
| """Generate psa_constant_names_generated.c |
| which is included by programs/psa/psa_constant_names.c. |
| The code generated by this module is only meant to be used in the context |
| of that program. |
| |
| An argument passed to this script will modify the output directory where the |
| file is written: |
| * by default (no arguments passed): writes to programs/psa/ |
| * OUTPUT_FILE_DIR passed: writes to OUTPUT_FILE_DIR/ |
| """ |
| |
| # 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 os |
| import re |
| import sys |
| |
| OUTPUT_TEMPLATE = '''\ |
| /* Automatically generated by generate_psa_constant.py. DO NOT EDIT. */ |
| |
| static const char *psa_strerror(psa_status_t status) |
| { |
| switch (status) { |
| %(status_cases)s |
| default: return NULL; |
| } |
| } |
| |
| static const char *psa_ecc_family_name(psa_ecc_family_t curve) |
| { |
| switch (curve) { |
| %(ecc_curve_cases)s |
| default: return NULL; |
| } |
| } |
| |
| static const char *psa_dh_family_name(psa_dh_family_t group) |
| { |
| switch (group) { |
| %(dh_group_cases)s |
| default: return NULL; |
| } |
| } |
| |
| static const char *psa_hash_algorithm_name(psa_algorithm_t hash_alg) |
| { |
| switch (hash_alg) { |
| %(hash_algorithm_cases)s |
| default: return NULL; |
| } |
| } |
| |
| static const char *psa_ka_algorithm_name(psa_algorithm_t ka_alg) |
| { |
| switch (ka_alg) { |
| %(ka_algorithm_cases)s |
| default: return NULL; |
| } |
| } |
| |
| static int psa_snprint_key_type(char *buffer, size_t buffer_size, |
| psa_key_type_t type) |
| { |
| size_t required_size = 0; |
| switch (type) { |
| %(key_type_cases)s |
| default: |
| %(key_type_code)s{ |
| return snprintf(buffer, buffer_size, |
| "0x%%04x", (unsigned) type); |
| } |
| break; |
| } |
| buffer[0] = 0; |
| return (int) required_size; |
| } |
| |
| #define NO_LENGTH_MODIFIER 0xfffffffflu |
| static int psa_snprint_algorithm(char *buffer, size_t buffer_size, |
| psa_algorithm_t alg) |
| { |
| size_t required_size = 0; |
| psa_algorithm_t core_alg = alg; |
| unsigned long length_modifier = NO_LENGTH_MODIFIER; |
| if (PSA_ALG_IS_MAC(alg)) { |
| core_alg = PSA_ALG_TRUNCATED_MAC(alg, 0); |
| if (core_alg != alg) { |
| append(&buffer, buffer_size, &required_size, |
| "PSA_ALG_TRUNCATED_MAC(", 22); |
| length_modifier = PSA_MAC_TRUNCATED_LENGTH(alg); |
| } |
| } else if (PSA_ALG_IS_AEAD(alg)) { |
| core_alg = PSA_ALG_AEAD_WITH_DEFAULT_TAG_LENGTH(alg); |
| if (core_alg == 0) { |
| /* For unknown AEAD algorithms, there is no "default tag length". */ |
| core_alg = alg; |
| } else if (core_alg != alg) { |
| append(&buffer, buffer_size, &required_size, |
| "PSA_ALG_AEAD_WITH_TAG_LENGTH(", 29); |
| length_modifier = PSA_AEAD_TAG_LENGTH(alg); |
| } |
| } else if (PSA_ALG_IS_KEY_AGREEMENT(alg) && |
| !PSA_ALG_IS_RAW_KEY_AGREEMENT(alg)) { |
| core_alg = PSA_ALG_KEY_AGREEMENT_GET_KDF(alg); |
| append(&buffer, buffer_size, &required_size, |
| "PSA_ALG_KEY_AGREEMENT(", 22); |
| append_with_alg(&buffer, buffer_size, &required_size, |
| psa_ka_algorithm_name, |
| PSA_ALG_KEY_AGREEMENT_GET_BASE(alg)); |
| append(&buffer, buffer_size, &required_size, ", ", 2); |
| } |
| switch (core_alg) { |
| %(algorithm_cases)s |
| default: |
| %(algorithm_code)s{ |
| append_integer(&buffer, buffer_size, &required_size, |
| "0x%%08lx", (unsigned long) core_alg); |
| } |
| break; |
| } |
| if (core_alg != alg) { |
| if (length_modifier != NO_LENGTH_MODIFIER) { |
| append(&buffer, buffer_size, &required_size, ", ", 2); |
| append_integer(&buffer, buffer_size, &required_size, |
| "%%lu", length_modifier); |
| } |
| append(&buffer, buffer_size, &required_size, ")", 1); |
| } |
| buffer[0] = 0; |
| return (int) required_size; |
| } |
| |
| static int psa_snprint_key_usage(char *buffer, size_t buffer_size, |
| psa_key_usage_t usage) |
| { |
| size_t required_size = 0; |
| if (usage == 0) { |
| if (buffer_size > 1) { |
| buffer[0] = '0'; |
| buffer[1] = 0; |
| } else if (buffer_size == 1) { |
| buffer[0] = 0; |
| } |
| return 1; |
| } |
| %(key_usage_code)s |
| if (usage != 0) { |
| if (required_size != 0) { |
| append(&buffer, buffer_size, &required_size, " | ", 3); |
| } |
| append_integer(&buffer, buffer_size, &required_size, |
| "0x%%08lx", (unsigned long) usage); |
| } else { |
| buffer[0] = 0; |
| } |
| return (int) required_size; |
| } |
| |
| /* End of automatically generated file. */ |
| ''' |
| |
| KEY_TYPE_FROM_CURVE_TEMPLATE = '''if (%(tester)s(type)) { |
| append_with_curve(&buffer, buffer_size, &required_size, |
| "%(builder)s", %(builder_length)s, |
| PSA_KEY_TYPE_ECC_GET_FAMILY(type)); |
| } else ''' |
| |
| KEY_TYPE_FROM_GROUP_TEMPLATE = '''if (%(tester)s(type)) { |
| append_with_group(&buffer, buffer_size, &required_size, |
| "%(builder)s", %(builder_length)s, |
| PSA_KEY_TYPE_DH_GET_FAMILY(type)); |
| } else ''' |
| |
| ALGORITHM_FROM_HASH_TEMPLATE = '''if (%(tester)s(core_alg)) { |
| append(&buffer, buffer_size, &required_size, |
| "%(builder)s(", %(builder_length)s + 1); |
| append_with_alg(&buffer, buffer_size, &required_size, |
| psa_hash_algorithm_name, |
| PSA_ALG_GET_HASH(core_alg)); |
| append(&buffer, buffer_size, &required_size, ")", 1); |
| } else ''' |
| |
| BIT_TEST_TEMPLATE = '''\ |
| if (%(var)s & %(flag)s) { |
| if (required_size != 0) { |
| append(&buffer, buffer_size, &required_size, " | ", 3); |
| } |
| append(&buffer, buffer_size, &required_size, "%(flag)s", %(length)d); |
| %(var)s ^= %(flag)s; |
| }\ |
| ''' |
| |
| class MacroCollector: |
| """Collect PSA crypto macro definitions from C header files. |
| |
| 1. Call `read_file` on the input header file(s). |
| 2. Call `write_file` to write ``psa_constant_names_generated.c``. |
| """ |
| |
| def __init__(self): |
| self.statuses = set() |
| self.key_types = set() |
| self.key_types_from_curve = {} |
| self.key_types_from_group = {} |
| self.ecc_curves = set() |
| self.dh_groups = set() |
| self.algorithms = set() |
| self.hash_algorithms = set() |
| self.ka_algorithms = set() |
| self.algorithms_from_hash = {} |
| self.key_usages = set() |
| |
| # "#define" followed by a macro name with either no parameters |
| # or a single parameter and a non-empty expansion. |
| # Grab the macro name in group 1, the parameter name if any in group 2 |
| # and the expansion in group 3. |
| _define_directive_re = re.compile(r'\s*#\s*define\s+(\w+)' + |
| r'(?:\s+|\((\w+)\)\s*)' + |
| r'(.+)') |
| _deprecated_definition_re = re.compile(r'\s*MBEDTLS_DEPRECATED') |
| |
| def read_line(self, line): |
| """Parse a C header line and record the PSA identifier it defines if any. |
| This function analyzes lines that start with "#define PSA_" |
| (up to non-significant whitespace) and skips all non-matching lines. |
| """ |
| # pylint: disable=too-many-branches |
| m = re.match(self._define_directive_re, line) |
| if not m: |
| return |
| name, parameter, expansion = m.groups() |
| expansion = re.sub(r'/\*.*?\*/|//.*', r' ', expansion) |
| if re.match(self._deprecated_definition_re, expansion): |
| # Skip deprecated values, which are assumed to be |
| # backward compatibility aliases that share |
| # numerical values with non-deprecated values. |
| return |
| if name.endswith('_FLAG') or name.endswith('MASK'): |
| # Macro only to build actual values |
| return |
| elif (name.startswith('PSA_ERROR_') or name == 'PSA_SUCCESS') \ |
| and not parameter: |
| self.statuses.add(name) |
| elif name.startswith('PSA_KEY_TYPE_') and not parameter: |
| self.key_types.add(name) |
| elif name.startswith('PSA_KEY_TYPE_') and parameter == 'curve': |
| self.key_types_from_curve[name] = name[:13] + 'IS_' + name[13:] |
| elif name.startswith('PSA_KEY_TYPE_') and parameter == 'group': |
| self.key_types_from_group[name] = name[:13] + 'IS_' + name[13:] |
| elif name.startswith('PSA_ECC_FAMILY_') and not parameter: |
| self.ecc_curves.add(name) |
| elif name.startswith('PSA_DH_FAMILY_') and not parameter: |
| self.dh_groups.add(name) |
| elif name.startswith('PSA_ALG_') and not parameter: |
| if name in ['PSA_ALG_ECDSA_BASE', |
| 'PSA_ALG_RSA_PKCS1V15_SIGN_BASE']: |
| # Ad hoc skipping of duplicate names for some numerical values |
| return |
| self.algorithms.add(name) |
| # Ad hoc detection of hash algorithms |
| if re.search(r'0x010000[0-9A-Fa-f]{2}', expansion): |
| self.hash_algorithms.add(name) |
| # Ad hoc detection of key agreement algorithms |
| if re.search(r'0x30[0-9A-Fa-f]{2}0000', expansion): |
| self.ka_algorithms.add(name) |
| elif name.startswith('PSA_ALG_') and parameter == 'hash_alg': |
| if name in ['PSA_ALG_DSA', 'PSA_ALG_ECDSA']: |
| # A naming irregularity |
| tester = name[:8] + 'IS_RANDOMIZED_' + name[8:] |
| else: |
| tester = name[:8] + 'IS_' + name[8:] |
| self.algorithms_from_hash[name] = tester |
| elif name.startswith('PSA_KEY_USAGE_') and not parameter: |
| self.key_usages.add(name) |
| else: |
| # Other macro without parameter |
| return |
| |
| _nonascii_re = re.compile(rb'[^\x00-\x7f]+') |
| _continued_line_re = re.compile(rb'\\\r?\n\Z') |
| def read_file(self, header_file): |
| for line in header_file: |
| m = re.search(self._continued_line_re, line) |
| while m: |
| cont = next(header_file) |
| line = line[:m.start(0)] + cont |
| m = re.search(self._continued_line_re, line) |
| line = re.sub(self._nonascii_re, rb'', line).decode('ascii') |
| self.read_line(line) |
| |
| @staticmethod |
| def _make_return_case(name): |
| return 'case %(name)s: return "%(name)s";' % {'name': name} |
| |
| @staticmethod |
| def _make_append_case(name): |
| template = ('case %(name)s: ' |
| 'append(&buffer, buffer_size, &required_size, "%(name)s", %(length)d); ' |
| 'break;') |
| return template % {'name': name, 'length': len(name)} |
| |
| @staticmethod |
| def _make_bit_test(var, flag): |
| return BIT_TEST_TEMPLATE % {'var': var, |
| 'flag': flag, |
| 'length': len(flag)} |
| |
| def _make_status_cases(self): |
| return '\n '.join(map(self._make_return_case, |
| sorted(self.statuses))) |
| |
| def _make_ecc_curve_cases(self): |
| return '\n '.join(map(self._make_return_case, |
| sorted(self.ecc_curves))) |
| |
| def _make_dh_group_cases(self): |
| return '\n '.join(map(self._make_return_case, |
| sorted(self.dh_groups))) |
| |
| def _make_key_type_cases(self): |
| return '\n '.join(map(self._make_append_case, |
| sorted(self.key_types))) |
| |
| @staticmethod |
| def _make_key_type_from_curve_code(builder, tester): |
| return KEY_TYPE_FROM_CURVE_TEMPLATE % {'builder': builder, |
| 'builder_length': len(builder), |
| 'tester': tester} |
| |
| @staticmethod |
| def _make_key_type_from_group_code(builder, tester): |
| return KEY_TYPE_FROM_GROUP_TEMPLATE % {'builder': builder, |
| 'builder_length': len(builder), |
| 'tester': tester} |
| |
| def _make_ecc_key_type_code(self): |
| d = self.key_types_from_curve |
| make = self._make_key_type_from_curve_code |
| return ''.join([make(k, d[k]) for k in sorted(d.keys())]) |
| |
| def _make_dh_key_type_code(self): |
| d = self.key_types_from_group |
| make = self._make_key_type_from_group_code |
| return ''.join([make(k, d[k]) for k in sorted(d.keys())]) |
| |
| def _make_hash_algorithm_cases(self): |
| return '\n '.join(map(self._make_return_case, |
| sorted(self.hash_algorithms))) |
| |
| def _make_ka_algorithm_cases(self): |
| return '\n '.join(map(self._make_return_case, |
| sorted(self.ka_algorithms))) |
| |
| def _make_algorithm_cases(self): |
| return '\n '.join(map(self._make_append_case, |
| sorted(self.algorithms))) |
| |
| @staticmethod |
| def _make_algorithm_from_hash_code(builder, tester): |
| return ALGORITHM_FROM_HASH_TEMPLATE % {'builder': builder, |
| 'builder_length': len(builder), |
| 'tester': tester} |
| |
| def _make_algorithm_code(self): |
| d = self.algorithms_from_hash |
| make = self._make_algorithm_from_hash_code |
| return ''.join([make(k, d[k]) for k in sorted(d.keys())]) |
| |
| def _make_key_usage_code(self): |
| return '\n'.join([self._make_bit_test('usage', bit) |
| for bit in sorted(self.key_usages)]) |
| |
| def write_file(self, output_file): |
| """Generate the pretty-printer function code from the gathered |
| constant definitions. |
| """ |
| data = {} |
| data['status_cases'] = self._make_status_cases() |
| data['ecc_curve_cases'] = self._make_ecc_curve_cases() |
| data['dh_group_cases'] = self._make_dh_group_cases() |
| data['key_type_cases'] = self._make_key_type_cases() |
| data['key_type_code'] = (self._make_ecc_key_type_code() + |
| self._make_dh_key_type_code()) |
| data['hash_algorithm_cases'] = self._make_hash_algorithm_cases() |
| data['ka_algorithm_cases'] = self._make_ka_algorithm_cases() |
| data['algorithm_cases'] = self._make_algorithm_cases() |
| data['algorithm_code'] = self._make_algorithm_code() |
| data['key_usage_code'] = self._make_key_usage_code() |
| output_file.write(OUTPUT_TEMPLATE % data) |
| |
| def generate_psa_constants(header_file_names, output_file_name): |
| collector = MacroCollector() |
| for header_file_name in header_file_names: |
| with open(header_file_name, 'rb') as header_file: |
| collector.read_file(header_file) |
| temp_file_name = output_file_name + '.tmp' |
| with open(temp_file_name, 'w') as output_file: |
| collector.write_file(output_file) |
| os.rename(temp_file_name, output_file_name) |
| |
| if __name__ == '__main__': |
| if not os.path.isdir('programs') and os.path.isdir('../programs'): |
| os.chdir('..') |
| # Allow to change the directory where psa_constant_names_generated.c is written to. |
| OUTPUT_FILE_DIR = sys.argv[1] if len(sys.argv) == 2 else "programs/psa" |
| generate_psa_constants(['include/psa/crypto_values.h', |
| 'include/psa/crypto_extra.h'], |
| OUTPUT_FILE_DIR + '/psa_constant_names_generated.c') |
