xref: /freebsd/crypto/openssl/crypto/threads_pthread.c (revision 1523ccfd9c8c254f7928143d31c305384b05fd11)
1 /*
2  * Copyright 2016-2026 The OpenSSL Project Authors. All Rights Reserved.
3  *
4  * Licensed under the Apache License 2.0 (the "License").  You may not use
5  * this file except in compliance with the License.  You can obtain a copy
6  * in the file LICENSE in the source distribution or at
7  * https://www.openssl.org/source/license.html
8  */
9 
10 /* We need to use the OPENSSL_fork_*() deprecated APIs */
11 #define OPENSSL_SUPPRESS_DEPRECATED
12 
13 #include <openssl/crypto.h>
14 #include <crypto/cryptlib.h>
15 #include "internal/cryptlib.h"
16 #include "internal/rcu.h"
17 #include "rcu_internal.h"
18 
19 #if defined(__clang__) && defined(__has_feature)
20 #if __has_feature(thread_sanitizer)
21 #define __SANITIZE_THREAD__
22 #endif
23 #endif
24 
25 #if defined(__SANITIZE_THREAD__)
26 #include <sanitizer/tsan_interface.h>
27 #define TSAN_FAKE_UNLOCK(x)          \
28     __tsan_mutex_pre_unlock((x), 0); \
29     __tsan_mutex_post_unlock((x), 0)
30 
31 #define TSAN_FAKE_LOCK(x)          \
32     __tsan_mutex_pre_lock((x), 0); \
33     __tsan_mutex_post_lock((x), 0, 0)
34 #else
35 #define TSAN_FAKE_UNLOCK(x)
36 #define TSAN_FAKE_LOCK(x)
37 #endif
38 
39 #if defined(__sun)
40 #include <atomic.h>
41 #endif
42 
43 #if defined(__apple_build_version__) && __apple_build_version__ < 6000000
44 /*
45  * OS/X 10.7 and 10.8 had a weird version of clang which has __ATOMIC_ACQUIRE and
46  * __ATOMIC_ACQ_REL but which expects only one parameter for __atomic_is_lock_free()
47  * rather than two which has signature __atomic_is_lock_free(sizeof(_Atomic(T))).
48  * All of this makes impossible to use __atomic_is_lock_free here.
49  *
50  * See: https://github.com/llvm/llvm-project/commit/a4c2602b714e6c6edb98164550a5ae829b2de760
51  */
52 #define BROKEN_CLANG_ATOMICS
53 #endif
54 
55 #if defined(OPENSSL_THREADS) && !defined(CRYPTO_TDEBUG) && !defined(OPENSSL_SYS_WINDOWS)
56 
57 #if defined(OPENSSL_SYS_UNIX)
58 #include <sys/types.h>
59 #include <unistd.h>
60 #endif
61 
62 #include <assert.h>
63 
64 /*
65  * The Non-Stop KLT thread model currently seems broken in its rwlock
66  * implementation
67  * Likewise is there a problem with the glibc implementation on riscv.
68  */
69 #if defined(PTHREAD_RWLOCK_INITIALIZER) && !defined(_KLT_MODEL_) \
70     && !defined(__riscv)
71 #define USE_RWLOCK
72 #endif
73 
74 /*
75  * For all GNU/clang atomic builtins, we also need fallbacks, to cover all
76  * other compilers.
77 
78  * Unfortunately, we can't do that with some "generic type", because there's no
79  * guarantee that the chosen generic type is large enough to cover all cases.
80  * Therefore, we implement fallbacks for each applicable type, with composed
81  * names that include the type they handle.
82  *
83  * (an anecdote: we previously tried to use |void *| as the generic type, with
84  * the thought that the pointer itself is the largest type.  However, this is
85  * not true on 32-bit pointer platforms, as a |uint64_t| is twice as large)
86  *
87  * All applicable ATOMIC_ macros take the intended type as first parameter, so
88  * they can map to the correct fallback function.  In the GNU/clang case, that
89  * parameter is simply ignored.
90  */
91 
92 /*
93  * Internal types used with the ATOMIC_ macros, to make it possible to compose
94  * fallback function names.
95  */
96 typedef void *pvoid;
97 
98 #if defined(__GNUC__) && defined(__ATOMIC_ACQUIRE) && !defined(BROKEN_CLANG_ATOMICS) \
99     && !defined(USE_ATOMIC_FALLBACKS)
100 #define ATOMIC_LOAD_N(t, p, o) __atomic_load_n(p, o)
101 #define ATOMIC_STORE_N(t, p, v, o) __atomic_store_n(p, v, o)
102 #define ATOMIC_STORE(t, p, v, o) __atomic_store(p, v, o)
103 #define ATOMIC_ADD_FETCH(p, v, o) __atomic_add_fetch(p, v, o)
104 #define ATOMIC_SUB_FETCH(p, v, o) __atomic_sub_fetch(p, v, o)
105 #else
106 static pthread_mutex_t atomic_sim_lock = PTHREAD_MUTEX_INITIALIZER;
107 
108 #define IMPL_fallback_atomic_load_n(t)                    \
109     static ossl_inline t fallback_atomic_load_n_##t(t *p) \
110     {                                                     \
111         t ret;                                            \
112                                                           \
113         pthread_mutex_lock(&atomic_sim_lock);             \
114         ret = *p;                                         \
115         pthread_mutex_unlock(&atomic_sim_lock);           \
116         return ret;                                       \
117     }
118 IMPL_fallback_atomic_load_n(uint32_t)
119     IMPL_fallback_atomic_load_n(uint64_t)
120         IMPL_fallback_atomic_load_n(pvoid)
121 
122 #define ATOMIC_LOAD_N(t, p, o) fallback_atomic_load_n_##t(p)
123 
124 #define IMPL_fallback_atomic_store_n(t)                         \
125     static ossl_inline t fallback_atomic_store_n_##t(t *p, t v) \
126     {                                                           \
127         t ret;                                                  \
128                                                                 \
129         pthread_mutex_lock(&atomic_sim_lock);                   \
130         ret = *p;                                               \
131         *p = v;                                                 \
132         pthread_mutex_unlock(&atomic_sim_lock);                 \
133         return ret;                                             \
134     }
135             IMPL_fallback_atomic_store_n(uint32_t)
136 
137 #define ATOMIC_STORE_N(t, p, v, o) fallback_atomic_store_n_##t(p, v)
138 
139 #define IMPL_fallback_atomic_store(t)                             \
140     static ossl_inline void fallback_atomic_store_##t(t *p, t *v) \
141     {                                                             \
142         pthread_mutex_lock(&atomic_sim_lock);                     \
143         *p = *v;                                                  \
144         pthread_mutex_unlock(&atomic_sim_lock);                   \
145     }
146                 IMPL_fallback_atomic_store(pvoid)
147 
148 #define ATOMIC_STORE(t, p, v, o) fallback_atomic_store_##t(p, v)
149 
150     /*
151      * The fallbacks that follow don't need any per type implementation, as
152      * they are designed for uint64_t only.  If there comes a time when multiple
153      * types need to be covered, it's relatively easy to refactor them the same
154      * way as the fallbacks above.
155      */
156 
157     static ossl_inline uint64_t fallback_atomic_add_fetch(uint64_t *p, uint64_t v)
158 {
159     uint64_t ret;
160 
161     pthread_mutex_lock(&atomic_sim_lock);
162     *p += v;
163     ret = *p;
164     pthread_mutex_unlock(&atomic_sim_lock);
165     return ret;
166 }
167 
168 #define ATOMIC_ADD_FETCH(p, v, o) fallback_atomic_add_fetch(p, v)
169 
170 static ossl_inline uint64_t fallback_atomic_sub_fetch(uint64_t *p, uint64_t v)
171 {
172     uint64_t ret;
173 
174     pthread_mutex_lock(&atomic_sim_lock);
175     *p -= v;
176     ret = *p;
177     pthread_mutex_unlock(&atomic_sim_lock);
178     return ret;
179 }
180 
181 #define ATOMIC_SUB_FETCH(p, v, o) fallback_atomic_sub_fetch(p, v)
182 #endif
183 
184 /*
185  * This is the core of an rcu lock. It tracks the readers and writers for the
186  * current quiescence point for a given lock. Users is the 64 bit value that
187  * stores the READERS/ID as defined above
188  *
189  */
190 struct rcu_qp {
191     uint64_t users;
192 };
193 
194 struct thread_qp {
195     struct rcu_qp *qp;
196     unsigned int depth;
197     CRYPTO_RCU_LOCK *lock;
198 };
199 
200 #define MAX_QPS 10
201 /*
202  * This is the per thread tracking data
203  * that is assigned to each thread participating
204  * in an rcu qp
205  *
206  * qp points to the qp that it last acquired
207  *
208  */
209 struct rcu_thr_data {
210     struct thread_qp thread_qps[MAX_QPS];
211 };
212 
213 /*
214  * This is the internal version of a CRYPTO_RCU_LOCK
215  * it is cast from CRYPTO_RCU_LOCK
216  */
217 struct rcu_lock_st {
218     /* Callbacks to call for next ossl_synchronize_rcu */
219     struct rcu_cb_item *cb_items;
220 
221     /* The context we are being created against */
222     OSSL_LIB_CTX *ctx;
223 
224     /* Array of quiescent points for synchronization */
225     struct rcu_qp *qp_group;
226 
227     /* rcu generation counter for in-order retirement */
228     uint32_t id_ctr;
229 
230     /* Number of elements in qp_group array */
231     uint32_t group_count;
232 
233     /* Index of the current qp in the qp_group array */
234     uint32_t reader_idx;
235 
236     /* value of the next id_ctr value to be retired */
237     uint32_t next_to_retire;
238 
239     /* index of the next free rcu_qp in the qp_group */
240     uint32_t current_alloc_idx;
241 
242     /* number of qp's in qp_group array currently being retired */
243     uint32_t writers_alloced;
244 
245     /* lock protecting write side operations */
246     pthread_mutex_t write_lock;
247 
248     /* lock protecting updates to writers_alloced/current_alloc_idx */
249     pthread_mutex_t alloc_lock;
250 
251     /* signal to wake threads waiting on alloc_lock */
252     pthread_cond_t alloc_signal;
253 
254     /* lock to enforce in-order retirement */
255     pthread_mutex_t prior_lock;
256 
257     /* signal to wake threads waiting on prior_lock */
258     pthread_cond_t prior_signal;
259 };
260 
261 /* Read side acquisition of the current qp */
262 static struct rcu_qp *get_hold_current_qp(struct rcu_lock_st *lock)
263 {
264     uint32_t qp_idx;
265 
266     /* get the current qp index */
267     for (;;) {
268         qp_idx = ATOMIC_LOAD_N(uint32_t, &lock->reader_idx, __ATOMIC_RELAXED);
269 
270         /*
271          * Notes on use of __ATOMIC_ACQUIRE
272          * We need to ensure the following:
273          * 1) That subsequent operations aren't optimized by hoisting them above
274          * this operation.  Specifically, we don't want the below re-load of
275          * qp_idx to get optimized away
276          * 2) We want to ensure that any updating of reader_idx on the write side
277          * of the lock is flushed from a local cpu cache so that we see any
278          * updates prior to the load.  This is a non-issue on cache coherent
279          * systems like x86, but is relevant on other arches
280          */
281         ATOMIC_ADD_FETCH(&lock->qp_group[qp_idx].users, (uint64_t)1,
282             __ATOMIC_ACQUIRE);
283 
284         /* if the idx hasn't changed, we're good, else try again */
285         if (qp_idx == ATOMIC_LOAD_N(uint32_t, &lock->reader_idx, __ATOMIC_ACQUIRE))
286             break;
287 
288         ATOMIC_SUB_FETCH(&lock->qp_group[qp_idx].users, (uint64_t)1,
289             __ATOMIC_RELAXED);
290     }
291 
292     return &lock->qp_group[qp_idx];
293 }
294 
295 static void ossl_rcu_free_local_data(void *arg)
296 {
297     OSSL_LIB_CTX *ctx = arg;
298     CRYPTO_THREAD_LOCAL *lkey = ossl_lib_ctx_get_rcukey(ctx);
299     struct rcu_thr_data *data = CRYPTO_THREAD_get_local(lkey);
300 
301     OPENSSL_free(data);
302     CRYPTO_THREAD_set_local(lkey, NULL);
303 }
304 
305 void ossl_rcu_read_lock(CRYPTO_RCU_LOCK *lock)
306 {
307     struct rcu_thr_data *data;
308     int i, available_qp = -1;
309     CRYPTO_THREAD_LOCAL *lkey = ossl_lib_ctx_get_rcukey(lock->ctx);
310 
311     /*
312      * we're going to access current_qp here so ask the
313      * processor to fetch it
314      */
315     data = CRYPTO_THREAD_get_local(lkey);
316 
317     if (data == NULL) {
318         data = OPENSSL_zalloc(sizeof(*data));
319         OPENSSL_assert(data != NULL);
320         CRYPTO_THREAD_set_local(lkey, data);
321         ossl_init_thread_start(NULL, lock->ctx, ossl_rcu_free_local_data);
322     }
323 
324     for (i = 0; i < MAX_QPS; i++) {
325         if (data->thread_qps[i].qp == NULL && available_qp == -1)
326             available_qp = i;
327         /* If we have a hold on this lock already, we're good */
328         if (data->thread_qps[i].lock == lock) {
329             data->thread_qps[i].depth++;
330             return;
331         }
332     }
333 
334     /*
335      * if we get here, then we don't have a hold on this lock yet
336      */
337     assert(available_qp != -1);
338 
339     data->thread_qps[available_qp].qp = get_hold_current_qp(lock);
340     data->thread_qps[available_qp].depth = 1;
341     data->thread_qps[available_qp].lock = lock;
342 }
343 
344 void ossl_rcu_read_unlock(CRYPTO_RCU_LOCK *lock)
345 {
346     int i;
347     CRYPTO_THREAD_LOCAL *lkey = ossl_lib_ctx_get_rcukey(lock->ctx);
348     struct rcu_thr_data *data = CRYPTO_THREAD_get_local(lkey);
349     uint64_t ret;
350 
351     assert(data != NULL);
352 
353     for (i = 0; i < MAX_QPS; i++) {
354         if (data->thread_qps[i].lock == lock) {
355             /*
356              * we have to use __ATOMIC_RELEASE here
357              * to ensure that all preceding read instructions complete
358              * before the decrement is visible to ossl_synchronize_rcu
359              */
360             data->thread_qps[i].depth--;
361             if (data->thread_qps[i].depth == 0) {
362                 ret = ATOMIC_SUB_FETCH(&data->thread_qps[i].qp->users,
363                     (uint64_t)1, __ATOMIC_RELEASE);
364                 OPENSSL_assert(ret != UINT64_MAX);
365                 data->thread_qps[i].qp = NULL;
366                 data->thread_qps[i].lock = NULL;
367             }
368             return;
369         }
370     }
371     /*
372      * If we get here, we're trying to unlock a lock that we never acquired -
373      * that's fatal.
374      */
375     assert(0);
376 }
377 
378 /*
379  * Write side allocation routine to get the current qp
380  * and replace it with a new one
381  */
382 static struct rcu_qp *update_qp(CRYPTO_RCU_LOCK *lock, uint32_t *curr_id)
383 {
384     uint32_t current_idx;
385 
386     pthread_mutex_lock(&lock->alloc_lock);
387 
388     /*
389      * we need at least one qp to be available with one
390      * left over, so that readers can start working on
391      * one that isn't yet being waited on
392      */
393     while (lock->group_count - lock->writers_alloced < 2)
394         /* we have to wait for one to be free */
395         pthread_cond_wait(&lock->alloc_signal, &lock->alloc_lock);
396 
397     current_idx = lock->current_alloc_idx;
398 
399     /* Allocate the qp */
400     lock->writers_alloced++;
401 
402     /* increment the allocation index */
403     lock->current_alloc_idx = (lock->current_alloc_idx + 1) % lock->group_count;
404 
405     *curr_id = lock->id_ctr;
406     lock->id_ctr++;
407 
408     /*
409      * make the current state of everything visible by this release
410      * when get_hold_current_qp acquires the next qp
411      */
412     ATOMIC_STORE_N(uint32_t, &lock->reader_idx, lock->current_alloc_idx,
413         __ATOMIC_RELEASE);
414 
415     /*
416      * this should make sure that the new value of reader_idx is visible in
417      * get_hold_current_qp, directly after incrementing the users count
418      */
419     ATOMIC_ADD_FETCH(&lock->qp_group[current_idx].users, (uint64_t)0,
420         __ATOMIC_RELEASE);
421 
422     /* wake up any waiters */
423     pthread_cond_signal(&lock->alloc_signal);
424     pthread_mutex_unlock(&lock->alloc_lock);
425     return &lock->qp_group[current_idx];
426 }
427 
428 static void retire_qp(CRYPTO_RCU_LOCK *lock, struct rcu_qp *qp)
429 {
430     pthread_mutex_lock(&lock->alloc_lock);
431     lock->writers_alloced--;
432     pthread_cond_signal(&lock->alloc_signal);
433     pthread_mutex_unlock(&lock->alloc_lock);
434 }
435 
436 static struct rcu_qp *allocate_new_qp_group(CRYPTO_RCU_LOCK *lock,
437     uint32_t count)
438 {
439     struct rcu_qp *new = OPENSSL_zalloc(sizeof(*new) * count);
440 
441     lock->group_count = count;
442     return new;
443 }
444 
445 void ossl_rcu_write_lock(CRYPTO_RCU_LOCK *lock)
446 {
447     pthread_mutex_lock(&lock->write_lock);
448     TSAN_FAKE_UNLOCK(&lock->write_lock);
449 }
450 
451 void ossl_rcu_write_unlock(CRYPTO_RCU_LOCK *lock)
452 {
453     TSAN_FAKE_LOCK(&lock->write_lock);
454     pthread_mutex_unlock(&lock->write_lock);
455 }
456 
457 void ossl_synchronize_rcu(CRYPTO_RCU_LOCK *lock)
458 {
459     struct rcu_qp *qp;
460     uint64_t count;
461     uint32_t curr_id;
462     struct rcu_cb_item *cb_items, *tmpcb;
463 
464     pthread_mutex_lock(&lock->write_lock);
465     cb_items = lock->cb_items;
466     lock->cb_items = NULL;
467     pthread_mutex_unlock(&lock->write_lock);
468 
469     qp = update_qp(lock, &curr_id);
470 
471     /* retire in order */
472     pthread_mutex_lock(&lock->prior_lock);
473     while (lock->next_to_retire != curr_id)
474         pthread_cond_wait(&lock->prior_signal, &lock->prior_lock);
475 
476     /*
477      * wait for the reader count to reach zero
478      * Note the use of __ATOMIC_ACQUIRE here to ensure that any
479      * prior __ATOMIC_RELEASE write operation in ossl_rcu_read_unlock
480      * is visible prior to our read
481      * however this is likely just necessary to silence a tsan warning
482      * because the read side should not do any write operation
483      * outside the atomic itself
484      */
485     do {
486         count = ATOMIC_LOAD_N(uint64_t, &qp->users, __ATOMIC_ACQUIRE);
487     } while (count != (uint64_t)0);
488 
489     lock->next_to_retire++;
490     pthread_cond_broadcast(&lock->prior_signal);
491     pthread_mutex_unlock(&lock->prior_lock);
492 
493     retire_qp(lock, qp);
494 
495     /* handle any callbacks that we have */
496     while (cb_items != NULL) {
497         tmpcb = cb_items;
498         cb_items = cb_items->next;
499         tmpcb->fn(tmpcb->data);
500         OPENSSL_free(tmpcb);
501     }
502 }
503 
504 CRYPTO_RCU_CB_ITEM *ossl_rcu_cb_item_new(void)
505 {
506     return OPENSSL_zalloc(sizeof(CRYPTO_RCU_CB_ITEM));
507 }
508 
509 void ossl_rcu_cb_item_free(CRYPTO_RCU_CB_ITEM *item)
510 {
511     OPENSSL_free(item);
512 }
513 
514 /*
515  * Note: This call assumes its made under the protection of
516  * ossl_rcu_write_lock
517  */
518 void ossl_rcu_call(CRYPTO_RCU_LOCK *lock, CRYPTO_RCU_CB_ITEM *item,
519     rcu_cb_fn cb, void *data)
520 {
521     item->fn = cb;
522     item->data = data;
523     item->next = lock->cb_items;
524     lock->cb_items = item;
525 }
526 
527 void *ossl_rcu_uptr_deref(void **p)
528 {
529     return ATOMIC_LOAD_N(pvoid, p, __ATOMIC_ACQUIRE);
530 }
531 
532 void ossl_rcu_assign_uptr(void **p, void **v)
533 {
534     ATOMIC_STORE(pvoid, p, v, __ATOMIC_RELEASE);
535 }
536 
537 CRYPTO_RCU_LOCK *ossl_rcu_lock_new(int num_writers, OSSL_LIB_CTX *ctx)
538 {
539     struct rcu_lock_st *new;
540     pthread_mutex_t *mutexes[3] = { NULL };
541     pthread_cond_t *conds[2] = { NULL };
542     int i;
543 
544     /*
545      * We need a minimum of 2 qp's
546      */
547     if (num_writers < 2)
548         num_writers = 2;
549 
550     ctx = ossl_lib_ctx_get_concrete(ctx);
551     if (ctx == NULL)
552         return 0;
553 
554     new = OPENSSL_zalloc(sizeof(*new));
555     if (new == NULL)
556         return NULL;
557 
558     new->ctx = ctx;
559     i = 0;
560     mutexes[i] = pthread_mutex_init(&new->write_lock, NULL) == 0 ? &new->write_lock : NULL;
561     if (mutexes[i++] == NULL)
562         goto err;
563     mutexes[i] = pthread_mutex_init(&new->prior_lock, NULL) == 0 ? &new->prior_lock : NULL;
564     if (mutexes[i++] == NULL)
565         goto err;
566     mutexes[i] = pthread_mutex_init(&new->alloc_lock, NULL) == 0 ? &new->alloc_lock : NULL;
567     if (mutexes[i++] == NULL)
568         goto err;
569     conds[i - 3] = pthread_cond_init(&new->prior_signal, NULL) == 0 ? &new->prior_signal : NULL;
570     if (conds[i - 3] == NULL)
571         goto err;
572     i++;
573     conds[i - 3] = pthread_cond_init(&new->alloc_signal, NULL) == 0 ? &new->alloc_signal : NULL;
574     if (conds[i - 3] == NULL)
575         goto err;
576     i++;
577     new->qp_group = allocate_new_qp_group(new, num_writers);
578     if (new->qp_group == NULL)
579         goto err;
580 
581     return new;
582 
583 err:
584     for (i = 0; i < 3; i++)
585         if (mutexes[i] != NULL)
586             pthread_mutex_destroy(mutexes[i]);
587     for (i = 0; i < 2; i++)
588         if (conds[i] != NULL)
589             pthread_cond_destroy(conds[i]);
590     OPENSSL_free(new->qp_group);
591     OPENSSL_free(new);
592     return NULL;
593 }
594 
595 void ossl_rcu_lock_free(CRYPTO_RCU_LOCK *lock)
596 {
597     struct rcu_lock_st *rlock = (struct rcu_lock_st *)lock;
598 
599     if (lock == NULL)
600         return;
601 
602     /* make sure we're synchronized */
603     ossl_synchronize_rcu(rlock);
604 
605     OPENSSL_free(rlock->qp_group);
606     /*
607      * Some targets (BSD) allocate heap when initializing
608      * a mutex or condition, to prevent leaks, those need
609      * to be destroyed here
610      */
611     pthread_mutex_destroy(&rlock->write_lock);
612     pthread_mutex_destroy(&rlock->prior_lock);
613     pthread_mutex_destroy(&rlock->alloc_lock);
614     pthread_cond_destroy(&rlock->prior_signal);
615     pthread_cond_destroy(&rlock->alloc_signal);
616 
617     /* There should only be a single qp left now */
618     OPENSSL_free(rlock);
619 }
620 
621 CRYPTO_RWLOCK *CRYPTO_THREAD_lock_new(void)
622 {
623 #ifdef USE_RWLOCK
624     CRYPTO_RWLOCK *lock;
625 
626     if ((lock = OPENSSL_zalloc(sizeof(pthread_rwlock_t))) == NULL)
627         /* Don't set error, to avoid recursion blowup. */
628         return NULL;
629 
630     if (pthread_rwlock_init(lock, NULL) != 0) {
631         OPENSSL_free(lock);
632         return NULL;
633     }
634 #else
635     pthread_mutexattr_t attr;
636     CRYPTO_RWLOCK *lock;
637 
638     if ((lock = OPENSSL_zalloc(sizeof(pthread_mutex_t))) == NULL)
639         /* Don't set error, to avoid recursion blowup. */
640         return NULL;
641 
642     /*
643      * We don't use recursive mutexes, but try to catch errors if we do.
644      */
645     pthread_mutexattr_init(&attr);
646 #if !defined(__TANDEM) && !defined(_SPT_MODEL_)
647 #if !defined(NDEBUG) && !defined(OPENSSL_NO_MUTEX_ERRORCHECK)
648     pthread_mutexattr_settype(&attr, PTHREAD_MUTEX_ERRORCHECK);
649 #endif
650 #else
651     /* The SPT Thread Library does not define MUTEX attributes. */
652 #endif
653 
654     if (pthread_mutex_init(lock, &attr) != 0) {
655         pthread_mutexattr_destroy(&attr);
656         OPENSSL_free(lock);
657         return NULL;
658     }
659 
660     pthread_mutexattr_destroy(&attr);
661 #endif
662 
663     return lock;
664 }
665 
666 __owur int CRYPTO_THREAD_read_lock(CRYPTO_RWLOCK *lock)
667 {
668 #ifdef USE_RWLOCK
669     if (!ossl_assert(pthread_rwlock_rdlock(lock) == 0))
670         return 0;
671 #else
672     if (pthread_mutex_lock(lock) != 0) {
673         assert(errno != EDEADLK && errno != EBUSY);
674         return 0;
675     }
676 #endif
677 
678     return 1;
679 }
680 
681 __owur int CRYPTO_THREAD_write_lock(CRYPTO_RWLOCK *lock)
682 {
683 #ifdef USE_RWLOCK
684     if (!ossl_assert(pthread_rwlock_wrlock(lock) == 0))
685         return 0;
686 #else
687     if (pthread_mutex_lock(lock) != 0) {
688         assert(errno != EDEADLK && errno != EBUSY);
689         return 0;
690     }
691 #endif
692 
693     return 1;
694 }
695 
696 int CRYPTO_THREAD_unlock(CRYPTO_RWLOCK *lock)
697 {
698 #ifdef USE_RWLOCK
699     if (pthread_rwlock_unlock(lock) != 0)
700         return 0;
701 #else
702     if (pthread_mutex_unlock(lock) != 0) {
703         assert(errno != EPERM);
704         return 0;
705     }
706 #endif
707 
708     return 1;
709 }
710 
711 void CRYPTO_THREAD_lock_free(CRYPTO_RWLOCK *lock)
712 {
713     if (lock == NULL)
714         return;
715 
716 #ifdef USE_RWLOCK
717     pthread_rwlock_destroy(lock);
718 #else
719     pthread_mutex_destroy(lock);
720 #endif
721     OPENSSL_free(lock);
722 
723     return;
724 }
725 
726 int CRYPTO_THREAD_run_once(CRYPTO_ONCE *once, void (*init)(void))
727 {
728     if (pthread_once(once, init) != 0)
729         return 0;
730 
731     return 1;
732 }
733 
734 int ossl_thread_init_local(CRYPTO_THREAD_LOCAL *key, void (*cleanup)(void *))
735 {
736 
737     if (pthread_key_create(key, cleanup) != 0)
738         return 0;
739 
740     return 1;
741 }
742 
743 void *CRYPTO_THREAD_get_local(CRYPTO_THREAD_LOCAL *key)
744 {
745     return pthread_getspecific(*key);
746 }
747 
748 int CRYPTO_THREAD_set_local(CRYPTO_THREAD_LOCAL *key, void *val)
749 {
750     if (pthread_setspecific(*key, val) != 0)
751         return 0;
752 
753     return 1;
754 }
755 
756 int CRYPTO_THREAD_cleanup_local(CRYPTO_THREAD_LOCAL *key)
757 {
758     if (pthread_key_delete(*key) != 0)
759         return 0;
760 
761     return 1;
762 }
763 
764 CRYPTO_THREAD_ID CRYPTO_THREAD_get_current_id(void)
765 {
766     return pthread_self();
767 }
768 
769 int CRYPTO_THREAD_compare_id(CRYPTO_THREAD_ID a, CRYPTO_THREAD_ID b)
770 {
771     return pthread_equal(a, b);
772 }
773 
774 int CRYPTO_atomic_add(int *val, int amount, int *ret, CRYPTO_RWLOCK *lock)
775 {
776 #if defined(__GNUC__) && defined(__ATOMIC_ACQ_REL) && !defined(BROKEN_CLANG_ATOMICS)
777     if (__atomic_is_lock_free(sizeof(*val), val)) {
778         *ret = __atomic_add_fetch(val, amount, __ATOMIC_ACQ_REL);
779         return 1;
780     }
781 #elif defined(__sun) && (defined(__SunOS_5_10) || defined(__SunOS_5_11))
782     /* This will work for all future Solaris versions. */
783     if (ret != NULL) {
784         *ret = atomic_add_int_nv((volatile unsigned int *)val, amount);
785         return 1;
786     }
787 #endif
788     if (lock == NULL || !CRYPTO_THREAD_write_lock(lock))
789         return 0;
790 
791     *val += amount;
792     *ret = *val;
793 
794     if (!CRYPTO_THREAD_unlock(lock))
795         return 0;
796 
797     return 1;
798 }
799 
800 int CRYPTO_atomic_add64(uint64_t *val, uint64_t op, uint64_t *ret,
801     CRYPTO_RWLOCK *lock)
802 {
803 #if defined(__GNUC__) && defined(__ATOMIC_ACQ_REL) && !defined(BROKEN_CLANG_ATOMICS)
804     if (__atomic_is_lock_free(sizeof(*val), val)) {
805         *ret = __atomic_add_fetch(val, op, __ATOMIC_ACQ_REL);
806         return 1;
807     }
808 #elif defined(__sun) && (defined(__SunOS_5_10) || defined(__SunOS_5_11))
809     /* This will work for all future Solaris versions. */
810     if (ret != NULL) {
811         *ret = atomic_add_64_nv(val, op);
812         return 1;
813     }
814 #endif
815     if (lock == NULL || !CRYPTO_THREAD_write_lock(lock))
816         return 0;
817     *val += op;
818     *ret = *val;
819 
820     if (!CRYPTO_THREAD_unlock(lock))
821         return 0;
822 
823     return 1;
824 }
825 
826 int CRYPTO_atomic_and(uint64_t *val, uint64_t op, uint64_t *ret,
827     CRYPTO_RWLOCK *lock)
828 {
829 #if defined(__GNUC__) && defined(__ATOMIC_ACQ_REL) && !defined(BROKEN_CLANG_ATOMICS)
830     if (__atomic_is_lock_free(sizeof(*val), val)) {
831         *ret = __atomic_and_fetch(val, op, __ATOMIC_ACQ_REL);
832         return 1;
833     }
834 #elif defined(__sun) && (defined(__SunOS_5_10) || defined(__SunOS_5_11))
835     /* This will work for all future Solaris versions. */
836     if (ret != NULL) {
837         *ret = atomic_and_64_nv(val, op);
838         return 1;
839     }
840 #endif
841     if (lock == NULL || !CRYPTO_THREAD_write_lock(lock))
842         return 0;
843     *val &= op;
844     *ret = *val;
845 
846     if (!CRYPTO_THREAD_unlock(lock))
847         return 0;
848 
849     return 1;
850 }
851 
852 int CRYPTO_atomic_or(uint64_t *val, uint64_t op, uint64_t *ret,
853     CRYPTO_RWLOCK *lock)
854 {
855 #if defined(__GNUC__) && defined(__ATOMIC_ACQ_REL) && !defined(BROKEN_CLANG_ATOMICS)
856     if (__atomic_is_lock_free(sizeof(*val), val)) {
857         *ret = __atomic_or_fetch(val, op, __ATOMIC_ACQ_REL);
858         return 1;
859     }
860 #elif defined(__sun) && (defined(__SunOS_5_10) || defined(__SunOS_5_11))
861     /* This will work for all future Solaris versions. */
862     if (ret != NULL) {
863         *ret = atomic_or_64_nv(val, op);
864         return 1;
865     }
866 #endif
867     if (lock == NULL || !CRYPTO_THREAD_write_lock(lock))
868         return 0;
869     *val |= op;
870     *ret = *val;
871 
872     if (!CRYPTO_THREAD_unlock(lock))
873         return 0;
874 
875     return 1;
876 }
877 
878 int CRYPTO_atomic_load(uint64_t *val, uint64_t *ret, CRYPTO_RWLOCK *lock)
879 {
880 #if defined(__GNUC__) && defined(__ATOMIC_ACQ_REL) && !defined(BROKEN_CLANG_ATOMICS)
881     if (__atomic_is_lock_free(sizeof(*val), val)) {
882         __atomic_load(val, ret, __ATOMIC_ACQUIRE);
883         return 1;
884     }
885 #elif defined(__sun) && (defined(__SunOS_5_10) || defined(__SunOS_5_11))
886     /* This will work for all future Solaris versions. */
887     if (ret != NULL) {
888         *ret = atomic_or_64_nv(val, 0);
889         return 1;
890     }
891 #endif
892     if (lock == NULL || !CRYPTO_THREAD_read_lock(lock))
893         return 0;
894     *ret = *val;
895     if (!CRYPTO_THREAD_unlock(lock))
896         return 0;
897 
898     return 1;
899 }
900 
901 int CRYPTO_atomic_store(uint64_t *dst, uint64_t val, CRYPTO_RWLOCK *lock)
902 {
903 #if defined(__GNUC__) && defined(__ATOMIC_ACQ_REL) && !defined(BROKEN_CLANG_ATOMICS)
904     if (__atomic_is_lock_free(sizeof(*dst), dst)) {
905         __atomic_store(dst, &val, __ATOMIC_RELEASE);
906         return 1;
907     }
908 #elif defined(__sun) && (defined(__SunOS_5_10) || defined(__SunOS_5_11))
909     /* This will work for all future Solaris versions. */
910     if (dst != NULL) {
911         atomic_swap_64(dst, val);
912         return 1;
913     }
914 #endif
915     if (lock == NULL || !CRYPTO_THREAD_write_lock(lock))
916         return 0;
917     *dst = val;
918     if (!CRYPTO_THREAD_unlock(lock))
919         return 0;
920 
921     return 1;
922 }
923 
924 int CRYPTO_atomic_load_int(int *val, int *ret, CRYPTO_RWLOCK *lock)
925 {
926 #if defined(__GNUC__) && defined(__ATOMIC_ACQ_REL) && !defined(BROKEN_CLANG_ATOMICS)
927     if (__atomic_is_lock_free(sizeof(*val), val)) {
928         __atomic_load(val, ret, __ATOMIC_ACQUIRE);
929         return 1;
930     }
931 #elif defined(__sun) && (defined(__SunOS_5_10) || defined(__SunOS_5_11))
932     /* This will work for all future Solaris versions. */
933     if (ret != NULL) {
934         *ret = (int)atomic_or_uint_nv((unsigned int *)val, 0);
935         return 1;
936     }
937 #endif
938     if (lock == NULL || !CRYPTO_THREAD_read_lock(lock))
939         return 0;
940     *ret = *val;
941     if (!CRYPTO_THREAD_unlock(lock))
942         return 0;
943 
944     return 1;
945 }
946 
947 #ifndef FIPS_MODULE
948 int openssl_init_fork_handlers(void)
949 {
950     return 1;
951 }
952 #endif /* FIPS_MODULE */
953 
954 int openssl_get_fork_id(void)
955 {
956     return getpid();
957 }
958 #endif
959