xref: /third_party/mbedtls/library/threading.c (revision a8e1175b)
1/*
2 *  Threading abstraction layer
3 *
4 *  Copyright The Mbed TLS Contributors
5 *  SPDX-License-Identifier: Apache-2.0 OR GPL-2.0-or-later
6 */
7
8/*
9 * Ensure gmtime_r is available even with -std=c99; must be defined before
10 * mbedtls_config.h, which pulls in glibc's features.h. Harmless on other platforms.
11 */
12#if !defined(_POSIX_C_SOURCE)
13#define _POSIX_C_SOURCE 200112L
14#endif
15
16#include "common.h"
17
18#if defined(MBEDTLS_THREADING_C)
19
20#include "mbedtls/threading.h"
21
22#if defined(MBEDTLS_HAVE_TIME_DATE) && !defined(MBEDTLS_PLATFORM_GMTIME_R_ALT)
23
24#if !defined(_WIN32) && (defined(unix) || \
25    defined(__unix) || defined(__unix__) || (defined(__APPLE__) && \
26    defined(__MACH__)))
27#include <unistd.h>
28#endif /* !_WIN32 && (unix || __unix || __unix__ ||
29        * (__APPLE__ && __MACH__)) */
30
31#if !((defined(_POSIX_VERSION) && _POSIX_VERSION >= 200809L) ||     \
32    (defined(_POSIX_THREAD_SAFE_FUNCTIONS) &&                     \
33    _POSIX_THREAD_SAFE_FUNCTIONS >= 200112L))
34/*
35 * This is a convenience shorthand macro to avoid checking the long
36 * preprocessor conditions above. Ideally, we could expose this macro in
37 * platform_util.h and simply use it in platform_util.c, threading.c and
38 * threading.h. However, this macro is not part of the Mbed TLS public API, so
39 * we keep it private by only defining it in this file
40 */
41
42#if !(defined(_WIN32) && !defined(EFIX64) && !defined(EFI32))
43#define THREADING_USE_GMTIME
44#endif /* ! ( defined(_WIN32) && !defined(EFIX64) && !defined(EFI32) ) */
45
46#endif /* !( ( defined(_POSIX_VERSION) && _POSIX_VERSION >= 200809L ) || \
47             ( defined(_POSIX_THREAD_SAFE_FUNCTIONS ) && \
48                _POSIX_THREAD_SAFE_FUNCTIONS >= 200112L ) ) */
49
50#endif /* MBEDTLS_HAVE_TIME_DATE && !MBEDTLS_PLATFORM_GMTIME_R_ALT */
51
52#if defined(MBEDTLS_THREADING_PTHREAD)
53static void threading_mutex_init_pthread(mbedtls_threading_mutex_t *mutex)
54{
55    if (mutex == NULL) {
56        return;
57    }
58
59    /* One problem here is that calling lock on a pthread mutex without first
60     * having initialised it is undefined behaviour. Obviously we cannot check
61     * this here in a thread safe manner without a significant performance
62     * hit, so state transitions are checked in tests only via the state
63     * variable. Please make sure any new mutex that gets added is exercised in
64     * tests; see tests/src/threading_helpers.c for more details. */
65    (void) pthread_mutex_init(&mutex->mutex, NULL);
66}
67
68static void threading_mutex_free_pthread(mbedtls_threading_mutex_t *mutex)
69{
70    if (mutex == NULL) {
71        return;
72    }
73
74    (void) pthread_mutex_destroy(&mutex->mutex);
75}
76
77static int threading_mutex_lock_pthread(mbedtls_threading_mutex_t *mutex)
78{
79    if (mutex == NULL) {
80        return MBEDTLS_ERR_THREADING_BAD_INPUT_DATA;
81    }
82
83    if (pthread_mutex_lock(&mutex->mutex) != 0) {
84        return MBEDTLS_ERR_THREADING_MUTEX_ERROR;
85    }
86
87    return 0;
88}
89
90static int threading_mutex_unlock_pthread(mbedtls_threading_mutex_t *mutex)
91{
92    if (mutex == NULL) {
93        return MBEDTLS_ERR_THREADING_BAD_INPUT_DATA;
94    }
95
96    if (pthread_mutex_unlock(&mutex->mutex) != 0) {
97        return MBEDTLS_ERR_THREADING_MUTEX_ERROR;
98    }
99
100    return 0;
101}
102
103void (*mbedtls_mutex_init)(mbedtls_threading_mutex_t *) = threading_mutex_init_pthread;
104void (*mbedtls_mutex_free)(mbedtls_threading_mutex_t *) = threading_mutex_free_pthread;
105int (*mbedtls_mutex_lock)(mbedtls_threading_mutex_t *) = threading_mutex_lock_pthread;
106int (*mbedtls_mutex_unlock)(mbedtls_threading_mutex_t *) = threading_mutex_unlock_pthread;
107
108/*
109 * With pthreads we can statically initialize mutexes
110 */
111#define MUTEX_INIT  = { PTHREAD_MUTEX_INITIALIZER, 1 }
112
113#endif /* MBEDTLS_THREADING_PTHREAD */
114
115#if defined(MBEDTLS_THREADING_ALT)
116static int threading_mutex_fail(mbedtls_threading_mutex_t *mutex)
117{
118    ((void) mutex);
119    return MBEDTLS_ERR_THREADING_BAD_INPUT_DATA;
120}
121static void threading_mutex_dummy(mbedtls_threading_mutex_t *mutex)
122{
123    ((void) mutex);
124    return;
125}
126
127void (*mbedtls_mutex_init)(mbedtls_threading_mutex_t *) = threading_mutex_dummy;
128void (*mbedtls_mutex_free)(mbedtls_threading_mutex_t *) = threading_mutex_dummy;
129int (*mbedtls_mutex_lock)(mbedtls_threading_mutex_t *) = threading_mutex_fail;
130int (*mbedtls_mutex_unlock)(mbedtls_threading_mutex_t *) = threading_mutex_fail;
131
132/*
133 * Set functions pointers and initialize global mutexes
134 */
135void mbedtls_threading_set_alt(void (*mutex_init)(mbedtls_threading_mutex_t *),
136                               void (*mutex_free)(mbedtls_threading_mutex_t *),
137                               int (*mutex_lock)(mbedtls_threading_mutex_t *),
138                               int (*mutex_unlock)(mbedtls_threading_mutex_t *))
139{
140    mbedtls_mutex_init = mutex_init;
141    mbedtls_mutex_free = mutex_free;
142    mbedtls_mutex_lock = mutex_lock;
143    mbedtls_mutex_unlock = mutex_unlock;
144
145#if defined(MBEDTLS_FS_IO)
146    mbedtls_mutex_init(&mbedtls_threading_readdir_mutex);
147#endif
148#if defined(THREADING_USE_GMTIME)
149    mbedtls_mutex_init(&mbedtls_threading_gmtime_mutex);
150#endif
151#if defined(MBEDTLS_PSA_CRYPTO_C)
152    mbedtls_mutex_init(&mbedtls_threading_key_slot_mutex);
153    mbedtls_mutex_init(&mbedtls_threading_psa_globaldata_mutex);
154    mbedtls_mutex_init(&mbedtls_threading_psa_rngdata_mutex);
155#endif
156}
157
158/*
159 * Free global mutexes
160 */
161void mbedtls_threading_free_alt(void)
162{
163#if defined(MBEDTLS_FS_IO)
164    mbedtls_mutex_free(&mbedtls_threading_readdir_mutex);
165#endif
166#if defined(THREADING_USE_GMTIME)
167    mbedtls_mutex_free(&mbedtls_threading_gmtime_mutex);
168#endif
169#if defined(MBEDTLS_PSA_CRYPTO_C)
170    mbedtls_mutex_free(&mbedtls_threading_key_slot_mutex);
171    mbedtls_mutex_free(&mbedtls_threading_psa_globaldata_mutex);
172    mbedtls_mutex_free(&mbedtls_threading_psa_rngdata_mutex);
173#endif
174}
175#endif /* MBEDTLS_THREADING_ALT */
176
177/*
178 * Define global mutexes
179 */
180#ifndef MUTEX_INIT
181#define MUTEX_INIT
182#endif
183#if defined(MBEDTLS_FS_IO)
184mbedtls_threading_mutex_t mbedtls_threading_readdir_mutex MUTEX_INIT;
185#endif
186#if defined(THREADING_USE_GMTIME)
187mbedtls_threading_mutex_t mbedtls_threading_gmtime_mutex MUTEX_INIT;
188#endif
189#if defined(MBEDTLS_PSA_CRYPTO_C)
190mbedtls_threading_mutex_t mbedtls_threading_key_slot_mutex MUTEX_INIT;
191mbedtls_threading_mutex_t mbedtls_threading_psa_globaldata_mutex MUTEX_INIT;
192mbedtls_threading_mutex_t mbedtls_threading_psa_rngdata_mutex MUTEX_INIT;
193#endif
194
195#endif /* MBEDTLS_THREADING_C */
196