1 /* Copyright (c) 2015, Google Inc.
2  *
3  * Permission to use, copy, modify, and/or distribute this software for any
4  * purpose with or without fee is hereby granted, provided that the above
5  * copyright notice and this permission notice appear in all copies.
6  *
7  * THE SOFTWARE IS PROVIDED "AS IS" AND THE AUTHOR DISCLAIMS ALL WARRANTIES
8  * WITH REGARD TO THIS SOFTWARE INCLUDING ALL IMPLIED WARRANTIES OF
9  * MERCHANTABILITY AND FITNESS. IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY
10  * SPECIAL, DIRECT, INDIRECT, OR CONSEQUENTIAL DAMAGES OR ANY DAMAGES
11  * WHATSOEVER RESULTING FROM LOSS OF USE, DATA OR PROFITS, WHETHER IN AN ACTION
12  * OF CONTRACT, NEGLIGENCE OR OTHER TORTIOUS ACTION, ARISING OUT OF OR IN
13  * CONNECTION WITH THE USE OR PERFORMANCE OF THIS SOFTWARE. */
14 
15 #include "internal.h"
16 
17 #if !defined(OPENSSL_WINDOWS) && !defined(OPENSSL_NO_THREADS)
18 
19 #include <pthread.h>
20 #include <stdio.h>
21 #include <stdlib.h>
22 #include <string.h>
23 
24 #include <openssl/mem.h>
25 #include <openssl/type_check.h>
26 
27 
28 OPENSSL_COMPILE_ASSERT(sizeof(CRYPTO_MUTEX) >= sizeof(pthread_rwlock_t),
29                        CRYPTO_MUTEX_too_small);
30 
CRYPTO_MUTEX_init(CRYPTO_MUTEX * lock)31 void CRYPTO_MUTEX_init(CRYPTO_MUTEX *lock) {
32   if (pthread_rwlock_init((pthread_rwlock_t *) lock, NULL) != 0) {
33     abort();
34   }
35 }
36 
CRYPTO_MUTEX_lock_read(CRYPTO_MUTEX * lock)37 void CRYPTO_MUTEX_lock_read(CRYPTO_MUTEX *lock) {
38   if (pthread_rwlock_rdlock((pthread_rwlock_t *) lock) != 0) {
39     abort();
40   }
41 }
42 
CRYPTO_MUTEX_lock_write(CRYPTO_MUTEX * lock)43 void CRYPTO_MUTEX_lock_write(CRYPTO_MUTEX *lock) {
44   if (pthread_rwlock_wrlock((pthread_rwlock_t *) lock) != 0) {
45     abort();
46   }
47 }
48 
CRYPTO_MUTEX_unlock(CRYPTO_MUTEX * lock)49 void CRYPTO_MUTEX_unlock(CRYPTO_MUTEX *lock) {
50   if (pthread_rwlock_unlock((pthread_rwlock_t *) lock) != 0) {
51     abort();
52   }
53 }
54 
CRYPTO_MUTEX_cleanup(CRYPTO_MUTEX * lock)55 void CRYPTO_MUTEX_cleanup(CRYPTO_MUTEX *lock) {
56   pthread_rwlock_destroy((pthread_rwlock_t *) lock);
57 }
58 
CRYPTO_STATIC_MUTEX_lock_read(struct CRYPTO_STATIC_MUTEX * lock)59 void CRYPTO_STATIC_MUTEX_lock_read(struct CRYPTO_STATIC_MUTEX *lock) {
60   if (pthread_rwlock_rdlock(&lock->lock) != 0) {
61     abort();
62   }
63 }
64 
CRYPTO_STATIC_MUTEX_lock_write(struct CRYPTO_STATIC_MUTEX * lock)65 void CRYPTO_STATIC_MUTEX_lock_write(struct CRYPTO_STATIC_MUTEX *lock) {
66   if (pthread_rwlock_wrlock(&lock->lock) != 0) {
67     abort();
68   }
69 }
70 
CRYPTO_STATIC_MUTEX_unlock(struct CRYPTO_STATIC_MUTEX * lock)71 void CRYPTO_STATIC_MUTEX_unlock(struct CRYPTO_STATIC_MUTEX *lock) {
72   if (pthread_rwlock_unlock(&lock->lock) != 0) {
73     abort();
74   }
75 }
76 
CRYPTO_once(CRYPTO_once_t * once,void (* init)(void))77 void CRYPTO_once(CRYPTO_once_t *once, void (*init)(void)) {
78   if (pthread_once(once, init) != 0) {
79     fprintf(stderr,
80             "pthread_once failed. Did you link against a threading library?\n");
81     abort();
82   }
83 }
84 
85 static pthread_mutex_t g_destructors_lock = PTHREAD_MUTEX_INITIALIZER;
86 static thread_local_destructor_t g_destructors[NUM_OPENSSL_THREAD_LOCALS];
87 
thread_local_destructor(void * arg)88 static void thread_local_destructor(void *arg) {
89   if (arg == NULL) {
90     return;
91   }
92 
93   thread_local_destructor_t destructors[NUM_OPENSSL_THREAD_LOCALS];
94   if (pthread_mutex_lock(&g_destructors_lock) != 0) {
95     return;
96   }
97   memcpy(destructors, g_destructors, sizeof(destructors));
98   pthread_mutex_unlock(&g_destructors_lock);
99 
100   unsigned i;
101   void **pointers = arg;
102   for (i = 0; i < NUM_OPENSSL_THREAD_LOCALS; i++) {
103     if (destructors[i] != NULL) {
104       destructors[i](pointers[i]);
105     }
106   }
107 
108   OPENSSL_free(pointers);
109 }
110 
111 static pthread_once_t g_thread_local_init_once = PTHREAD_ONCE_INIT;
112 static pthread_key_t g_thread_local_key;
113 static int g_thread_local_failed = 0;
114 
thread_local_init(void)115 static void thread_local_init(void) {
116   g_thread_local_failed =
117       pthread_key_create(&g_thread_local_key, thread_local_destructor) != 0;
118 }
119 
CRYPTO_get_thread_local(thread_local_data_t index)120 void *CRYPTO_get_thread_local(thread_local_data_t index) {
121   CRYPTO_once(&g_thread_local_init_once, thread_local_init);
122   if (g_thread_local_failed) {
123     return NULL;
124   }
125 
126   void **pointers = pthread_getspecific(g_thread_local_key);
127   if (pointers == NULL) {
128     return NULL;
129   }
130   return pointers[index];
131 }
132 
CRYPTO_set_thread_local(thread_local_data_t index,void * value,thread_local_destructor_t destructor)133 int CRYPTO_set_thread_local(thread_local_data_t index, void *value,
134                             thread_local_destructor_t destructor) {
135   CRYPTO_once(&g_thread_local_init_once, thread_local_init);
136   if (g_thread_local_failed) {
137     destructor(value);
138     return 0;
139   }
140 
141   void **pointers = pthread_getspecific(g_thread_local_key);
142   if (pointers == NULL) {
143     pointers = OPENSSL_malloc(sizeof(void *) * NUM_OPENSSL_THREAD_LOCALS);
144     if (pointers == NULL) {
145       destructor(value);
146       return 0;
147     }
148     memset(pointers, 0, sizeof(void *) * NUM_OPENSSL_THREAD_LOCALS);
149     if (pthread_setspecific(g_thread_local_key, pointers) != 0) {
150       OPENSSL_free(pointers);
151       destructor(value);
152       return 0;
153     }
154   }
155 
156   if (pthread_mutex_lock(&g_destructors_lock) != 0) {
157     destructor(value);
158     return 0;
159   }
160   g_destructors[index] = destructor;
161   pthread_mutex_unlock(&g_destructors_lock);
162 
163   pointers[index] = value;
164   return 1;
165 }
166 
167 #endif  /* !OPENSSL_WINDOWS && !OPENSSL_NO_THREADS */
168