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 /* A nonzero value of is_valid indicates a successfully initialized
71 * mutex. This is a workaround for not being able to return an error
72 * code for this function. The lock/unlock functions return an error
73 * if is_valid is nonzero. The Mbed TLS unit test code uses this field
74 * to distinguish more states of the mutex; see
75 * tests/src/threading_helpers for details. */
76 mutex->is_valid = pthread_mutex_init( &mutex->mutex, NULL ) == 0;
77 }
78
threading_mutex_free_pthread(mbedtls_threading_mutex_t * mutex)79 static void threading_mutex_free_pthread( mbedtls_threading_mutex_t *mutex )
80 {
81 if( mutex == NULL || !mutex->is_valid )
82 return;
83
84 (void) pthread_mutex_destroy( &mutex->mutex );
85 mutex->is_valid = 0;
86 }
87
threading_mutex_lock_pthread(mbedtls_threading_mutex_t * mutex)88 static int threading_mutex_lock_pthread( mbedtls_threading_mutex_t *mutex )
89 {
90 if( mutex == NULL || ! mutex->is_valid )
91 return( MBEDTLS_ERR_THREADING_BAD_INPUT_DATA );
92
93 if( pthread_mutex_lock( &mutex->mutex ) != 0 )
94 return( MBEDTLS_ERR_THREADING_MUTEX_ERROR );
95
96 return( 0 );
97 }
98
threading_mutex_unlock_pthread(mbedtls_threading_mutex_t * mutex)99 static int threading_mutex_unlock_pthread( mbedtls_threading_mutex_t *mutex )
100 {
101 if( mutex == NULL || ! mutex->is_valid )
102 return( MBEDTLS_ERR_THREADING_BAD_INPUT_DATA );
103
104 if( pthread_mutex_unlock( &mutex->mutex ) != 0 )
105 return( MBEDTLS_ERR_THREADING_MUTEX_ERROR );
106
107 return( 0 );
108 }
109
110 void (*mbedtls_mutex_init)( mbedtls_threading_mutex_t * ) = threading_mutex_init_pthread;
111 void (*mbedtls_mutex_free)( mbedtls_threading_mutex_t * ) = threading_mutex_free_pthread;
112 int (*mbedtls_mutex_lock)( mbedtls_threading_mutex_t * ) = threading_mutex_lock_pthread;
113 int (*mbedtls_mutex_unlock)( mbedtls_threading_mutex_t * ) = threading_mutex_unlock_pthread;
114
115 /*
116 * With pthreads we can statically initialize mutexes
117 */
118 #define MUTEX_INIT = { PTHREAD_MUTEX_INITIALIZER, 1 }
119
120 #endif /* MBEDTLS_THREADING_PTHREAD */
121
122 #if defined(MBEDTLS_THREADING_ALT)
threading_mutex_fail(mbedtls_threading_mutex_t * mutex)123 static int threading_mutex_fail( mbedtls_threading_mutex_t *mutex )
124 {
125 ((void) mutex );
126 return( MBEDTLS_ERR_THREADING_BAD_INPUT_DATA );
127 }
threading_mutex_dummy(mbedtls_threading_mutex_t * mutex)128 static void threading_mutex_dummy( mbedtls_threading_mutex_t *mutex )
129 {
130 ((void) mutex );
131 return;
132 }
133
134 void (*mbedtls_mutex_init)( mbedtls_threading_mutex_t * ) = threading_mutex_dummy;
135 void (*mbedtls_mutex_free)( mbedtls_threading_mutex_t * ) = threading_mutex_dummy;
136 int (*mbedtls_mutex_lock)( mbedtls_threading_mutex_t * ) = threading_mutex_fail;
137 int (*mbedtls_mutex_unlock)( mbedtls_threading_mutex_t * ) = threading_mutex_fail;
138
139 /*
140 * Set functions pointers and initialize global mutexes
141 */
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 *))142 void mbedtls_threading_set_alt( void (*mutex_init)( mbedtls_threading_mutex_t * ),
143 void (*mutex_free)( mbedtls_threading_mutex_t * ),
144 int (*mutex_lock)( mbedtls_threading_mutex_t * ),
145 int (*mutex_unlock)( mbedtls_threading_mutex_t * ) )
146 {
147 mbedtls_mutex_init = mutex_init;
148 mbedtls_mutex_free = mutex_free;
149 mbedtls_mutex_lock = mutex_lock;
150 mbedtls_mutex_unlock = mutex_unlock;
151
152 #if defined(MBEDTLS_FS_IO)
153 mbedtls_mutex_init( &mbedtls_threading_readdir_mutex );
154 #endif
155 #if defined(THREADING_USE_GMTIME)
156 mbedtls_mutex_init( &mbedtls_threading_gmtime_mutex );
157 #endif
158 }
159
160 /*
161 * Free global mutexes
162 */
mbedtls_threading_free_alt(void)163 void mbedtls_threading_free_alt( void )
164 {
165 #if defined(MBEDTLS_FS_IO)
166 mbedtls_mutex_free( &mbedtls_threading_readdir_mutex );
167 #endif
168 #if defined(THREADING_USE_GMTIME)
169 mbedtls_mutex_free( &mbedtls_threading_gmtime_mutex );
170 #endif
171 }
172 #endif /* MBEDTLS_THREADING_ALT */
173
174 /*
175 * Define global mutexes
176 */
177 #ifndef MUTEX_INIT
178 #define MUTEX_INIT
179 #endif
180 #if defined(MBEDTLS_FS_IO)
181 mbedtls_threading_mutex_t mbedtls_threading_readdir_mutex MUTEX_INIT;
182 #endif
183 #if defined(THREADING_USE_GMTIME)
184 mbedtls_threading_mutex_t mbedtls_threading_gmtime_mutex MUTEX_INIT;
185 #endif
186
187 #endif /* MBEDTLS_THREADING_C */
188
