| #!/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 OR GPL-2.0-or-later |
| |
| import os |
| import sys |
| |
| from mbedtls_dev import build_tree |
| from mbedtls_dev import macro_collector |
| |
| 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 (alg & PSA_ALG_MAC_AT_LEAST_THIS_LENGTH_FLAG) { |
| append(&buffer, buffer_size, &required_size, |
| "PSA_ALG_AT_LEAST_THIS_LENGTH_MAC(", 33); |
| length_modifier = PSA_MAC_TRUNCATED_LENGTH(alg); |
| } else 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_LENGTH_TAG(alg); |
| if (core_alg == 0) { |
| /* For unknown AEAD algorithms, there is no "default tag length". */ |
| core_alg = alg; |
| } else if (alg & PSA_ALG_AEAD_AT_LEAST_THIS_LENGTH_FLAG) { |
| append(&buffer, buffer_size, &required_size, |
| "PSA_ALG_AEAD_WITH_AT_LEAST_THIS_LENGTH_TAG(", 43); |
| length_modifier = PSA_ALG_AEAD_GET_TAG_LENGTH(alg); |
| } else if (core_alg != alg) { |
| append(&buffer, buffer_size, &required_size, |
| "PSA_ALG_AEAD_WITH_SHORTENED_TAG(", 32); |
| length_modifier = PSA_ALG_AEAD_GET_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 CaseBuilder(macro_collector.PSAMacroCollector): |
| """Collect PSA crypto macro definitions and write value recognition functions. |
| |
| 1. Call `read_file` on the input header file(s). |
| 2. Call `write_file` to write ``psa_constant_names_generated.c``. |
| """ |
| |
| def __init__(self): |
| super().__init__(include_intermediate=True) |
| |
| @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_usage_flags)]) |
| |
| 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 = CaseBuilder() |
| 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.replace(temp_file_name, output_file_name) |
| |
| if __name__ == '__main__': |
| build_tree.chdir_to_root() |
| # 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') |