1 /* 2 * Threading abstraction layer 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 */ 19 20 /* 21 * Ensure gmtime_r is available even with -std=c99; must be defined before 22 * mbedtls_config.h, which pulls in glibc's features.h. Harmless on other platforms. 23 */ 24 #if !defined(_POSIX_C_SOURCE) 25 #define _POSIX_C_SOURCE 200112L 26 #endif 27 28 #include "common.h" 29 30 #if defined(MBEDTLS_THREADING_C) 31 32 #include "mbedtls/threading.h" 33 34 #if defined(MBEDTLS_HAVE_TIME_DATE) && !defined(MBEDTLS_PLATFORM_GMTIME_R_ALT) 35 36 #if !defined(_WIN32) && (defined(unix) || \ 37 defined(__unix) || defined(__unix__) || (defined(__APPLE__) && \ 38 defined(__MACH__))) 39 #include <unistd.h> 40 #endif /* !_WIN32 && (unix || __unix || __unix__ || 41 * (__APPLE__ && __MACH__)) */ 42 43 #if !((defined(_POSIX_VERSION) && _POSIX_VERSION >= 200809L) || \ 44 (defined(_POSIX_THREAD_SAFE_FUNCTIONS) && \ 45 _POSIX_THREAD_SAFE_FUNCTIONS >= 200112L)) 46 /* 47 * This is a convenience shorthand macro to avoid checking the long 48 * preprocessor conditions above. Ideally, we could expose this macro in 49 * platform_util.h and simply use it in platform_util.c, threading.c and 50 * threading.h. However, this macro is not part of the Mbed TLS public API, so 51 * we keep it private by only defining it in this file 52 */ 53 54 #if !(defined(_WIN32) && !defined(EFIX64) && !defined(EFI32)) 55 #define THREADING_USE_GMTIME 56 #endif /* ! ( defined(_WIN32) && !defined(EFIX64) && !defined(EFI32) ) */ 57 58 #endif /* !( ( defined(_POSIX_VERSION) && _POSIX_VERSION >= 200809L ) || \ 59 ( defined(_POSIX_THREAD_SAFE_FUNCTIONS ) && \ 60 _POSIX_THREAD_SAFE_FUNCTIONS >= 200112L ) ) */ 61 62 #endif /* MBEDTLS_HAVE_TIME_DATE && !MBEDTLS_PLATFORM_GMTIME_R_ALT */ 63 64 #if defined(MBEDTLS_THREADING_PTHREAD) 65 static void threading_mutex_init_pthread(mbedtls_threading_mutex_t *mutex) 66 { 67 if (mutex == NULL) { 68 return; 69 } 70 71 /* A nonzero value of is_valid indicates a successfully initialized 72 * mutex. This is a workaround for not being able to return an error 73 * code for this function. The lock/unlock functions return an error 74 * if is_valid is nonzero. The Mbed TLS unit test code uses this field 75 * to distinguish more states of the mutex; see 76 * tests/src/threading_helpers for details. */ 77 mutex->is_valid = pthread_mutex_init(&mutex->mutex, NULL) == 0; 78 } 79 80 static void threading_mutex_free_pthread(mbedtls_threading_mutex_t *mutex) 81 { 82 if (mutex == NULL || !mutex->is_valid) { 83 return; 84 } 85 86 (void) pthread_mutex_destroy(&mutex->mutex); 87 mutex->is_valid = 0; 88 } 89 90 static int threading_mutex_lock_pthread(mbedtls_threading_mutex_t *mutex) 91 { 92 if (mutex == NULL || !mutex->is_valid) { 93 return MBEDTLS_ERR_THREADING_BAD_INPUT_DATA; 94 } 95 96 if (pthread_mutex_lock(&mutex->mutex) != 0) { 97 return MBEDTLS_ERR_THREADING_MUTEX_ERROR; 98 } 99 100 return 0; 101 } 102 103 static int threading_mutex_unlock_pthread(mbedtls_threading_mutex_t *mutex) 104 { 105 if (mutex == NULL || !mutex->is_valid) { 106 return MBEDTLS_ERR_THREADING_BAD_INPUT_DATA; 107 } 108 109 if (pthread_mutex_unlock(&mutex->mutex) != 0) { 110 return MBEDTLS_ERR_THREADING_MUTEX_ERROR; 111 } 112 113 return 0; 114 } 115 116 void (*mbedtls_mutex_init)(mbedtls_threading_mutex_t *) = threading_mutex_init_pthread; 117 void (*mbedtls_mutex_free)(mbedtls_threading_mutex_t *) = threading_mutex_free_pthread; 118 int (*mbedtls_mutex_lock)(mbedtls_threading_mutex_t *) = threading_mutex_lock_pthread; 119 int (*mbedtls_mutex_unlock)(mbedtls_threading_mutex_t *) = threading_mutex_unlock_pthread; 120 121 /* 122 * With pthreads we can statically initialize mutexes 123 */ 124 #define MUTEX_INIT = { PTHREAD_MUTEX_INITIALIZER, 1 } 125 126 #endif /* MBEDTLS_THREADING_PTHREAD */ 127 128 #if defined(MBEDTLS_THREADING_ALT) 129 static int threading_mutex_fail(mbedtls_threading_mutex_t *mutex) 130 { 131 ((void) mutex); 132 return MBEDTLS_ERR_THREADING_BAD_INPUT_DATA; 133 } 134 static void threading_mutex_dummy(mbedtls_threading_mutex_t *mutex) 135 { 136 ((void) mutex); 137 return; 138 } 139 140 void (*mbedtls_mutex_init)(mbedtls_threading_mutex_t *) = threading_mutex_dummy; 141 void (*mbedtls_mutex_free)(mbedtls_threading_mutex_t *) = threading_mutex_dummy; 142 int (*mbedtls_mutex_lock)(mbedtls_threading_mutex_t *) = threading_mutex_fail; 143 int (*mbedtls_mutex_unlock)(mbedtls_threading_mutex_t *) = threading_mutex_fail; 144 145 /* 146 * Set functions pointers and initialize global mutexes 147 */ 148 void mbedtls_threading_set_alt(void (*mutex_init)(mbedtls_threading_mutex_t *), 149 void (*mutex_free)(mbedtls_threading_mutex_t *), 150 int (*mutex_lock)(mbedtls_threading_mutex_t *), 151 int (*mutex_unlock)(mbedtls_threading_mutex_t *)) 152 { 153 mbedtls_mutex_init = mutex_init; 154 mbedtls_mutex_free = mutex_free; 155 mbedtls_mutex_lock = mutex_lock; 156 mbedtls_mutex_unlock = mutex_unlock; 157 158 #if defined(MBEDTLS_FS_IO) 159 mbedtls_mutex_init(&mbedtls_threading_readdir_mutex); 160 #endif 161 #if defined(THREADING_USE_GMTIME) 162 mbedtls_mutex_init(&mbedtls_threading_gmtime_mutex); 163 #endif 164 } 165 166 /* 167 * Free global mutexes 168 */ 169 void mbedtls_threading_free_alt(void) 170 { 171 #if defined(MBEDTLS_FS_IO) 172 mbedtls_mutex_free(&mbedtls_threading_readdir_mutex); 173 #endif 174 #if defined(THREADING_USE_GMTIME) 175 mbedtls_mutex_free(&mbedtls_threading_gmtime_mutex); 176 #endif 177 } 178 #endif /* MBEDTLS_THREADING_ALT */ 179 180 /* 181 * Define global mutexes 182 */ 183 #ifndef MUTEX_INIT 184 #define MUTEX_INIT 185 #endif 186 #if defined(MBEDTLS_FS_IO) 187 mbedtls_threading_mutex_t mbedtls_threading_readdir_mutex MUTEX_INIT; 188 #endif 189 #if defined(THREADING_USE_GMTIME) 190 mbedtls_threading_mutex_t mbedtls_threading_gmtime_mutex MUTEX_INIT; 191 #endif 192 193 #endif /* MBEDTLS_THREADING_C */ 194