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)
threading_mutex_init_pthread(mbedtls_threading_mutex_t * mutex)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
threading_mutex_free_pthread(mbedtls_threading_mutex_t * mutex)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
threading_mutex_lock_pthread(mbedtls_threading_mutex_t * mutex)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
threading_mutex_unlock_pthread(mbedtls_threading_mutex_t * mutex)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)
threading_mutex_fail(mbedtls_threading_mutex_t * mutex)129 static int threading_mutex_fail(mbedtls_threading_mutex_t *mutex)
130 {
131 ((void) mutex);
132 return MBEDTLS_ERR_THREADING_BAD_INPUT_DATA;
133 }
threading_mutex_dummy(mbedtls_threading_mutex_t * mutex)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 */
mbedtls_threading_set_alt(void (* mutex_init)(mbedtls_threading_mutex_t *),void (* mutex_free)(mbedtls_threading_mutex_t *),int (* mutex_lock)(mbedtls_threading_mutex_t *),int (* mutex_unlock)(mbedtls_threading_mutex_t *))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 */
mbedtls_threading_free_alt(void)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