2 * Copyright 2016-2018 The OpenSSL Project Authors. All Rights Reserved.
4 * Licensed under the OpenSSL license (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
11 #include "internal/cryptlib_int.h"
12 #include <openssl/err.h>
13 #include "internal/rand_int.h"
14 #include "internal/bio.h"
15 #include <openssl/evp.h>
16 #include "internal/evp_int.h"
17 #include "internal/conf.h"
18 #include "internal/async.h"
19 #include "internal/engine.h"
20 #include "internal/comp.h"
21 #include "internal/err.h"
22 #include "internal/err_int.h"
23 #include "internal/objects.h"
26 #include "internal/thread_once.h"
27 #include "internal/dso_conf.h"
28 #include "internal/dso.h"
29 #include "internal/store.h"
31 static int stopped = 0;
34 * Since per-thread-specific-data destructors are not universally
35 * available, i.e. not on Windows, only below CRYPTO_THREAD_LOCAL key
36 * is assumed to have destructor associated. And then an effort is made
37 * to call this single destructor on non-pthread platform[s].
39 * Initial value is "impossible". It is used as guard value to shortcut
40 * destructor for threads terminating before libcrypto is initialized or
41 * after it's de-initialized. Access to the key doesn't have to be
42 * serialized for the said threads, because they didn't use libcrypto
43 * and it doesn't matter if they pick "impossible" or derefernce real
44 * key value and pull NULL past initialization in the first thread that
45 * intends to use libcrypto.
49 CRYPTO_THREAD_LOCAL value;
50 } destructor_key = { -1 };
52 static void ossl_init_thread_stop(struct thread_local_inits_st *locals);
54 static void ossl_init_thread_destructor(void *local)
56 ossl_init_thread_stop((struct thread_local_inits_st *)local);
59 static struct thread_local_inits_st *ossl_init_get_thread_local(int alloc)
61 struct thread_local_inits_st *local =
62 CRYPTO_THREAD_get_local(&destructor_key.value);
66 && (local = OPENSSL_zalloc(sizeof(*local))) != NULL
67 && !CRYPTO_THREAD_set_local(&destructor_key.value, local)) {
72 CRYPTO_THREAD_set_local(&destructor_key.value, NULL);
78 typedef struct ossl_init_stop_st OPENSSL_INIT_STOP;
79 struct ossl_init_stop_st {
80 void (*handler)(void);
81 OPENSSL_INIT_STOP *next;
84 static OPENSSL_INIT_STOP *stop_handlers = NULL;
85 static CRYPTO_RWLOCK *init_lock = NULL;
87 static CRYPTO_ONCE base = CRYPTO_ONCE_STATIC_INIT;
88 static int base_inited = 0;
89 DEFINE_RUN_ONCE_STATIC(ossl_init_base)
91 CRYPTO_THREAD_LOCAL key;
93 #ifdef OPENSSL_INIT_DEBUG
94 fprintf(stderr, "OPENSSL_INIT: ossl_init_base: Setting up stop handlers\n");
96 #ifndef OPENSSL_NO_CRYPTO_MDEBUG
97 ossl_malloc_setup_failures();
99 if (!CRYPTO_THREAD_init_local(&key, ossl_init_thread_destructor))
101 if ((init_lock = CRYPTO_THREAD_lock_new()) == NULL)
103 #ifndef OPENSSL_SYS_UEFI
104 if (atexit(OPENSSL_cleanup) != 0)
107 OPENSSL_cpuid_setup();
109 destructor_key.value = key;
114 #ifdef OPENSSL_INIT_DEBUG
115 fprintf(stderr, "OPENSSL_INIT: ossl_init_base not ok!\n");
117 CRYPTO_THREAD_lock_free(init_lock);
120 CRYPTO_THREAD_cleanup_local(&key);
124 static CRYPTO_ONCE load_crypto_nodelete = CRYPTO_ONCE_STATIC_INIT;
125 DEFINE_RUN_ONCE_STATIC(ossl_init_load_crypto_nodelete)
127 #ifdef OPENSSL_INIT_DEBUG
128 fprintf(stderr, "OPENSSL_INIT: ossl_init_load_crypto_nodelete()\n");
130 #if !defined(OPENSSL_NO_DSO) && !defined(OPENSSL_USE_NODELETE)
133 HMODULE handle = NULL;
136 /* We don't use the DSO route for WIN32 because there is a better way */
137 ret = GetModuleHandleEx(GET_MODULE_HANDLE_EX_FLAG_FROM_ADDRESS
138 | GET_MODULE_HANDLE_EX_FLAG_PIN,
139 (void *)&base_inited, &handle);
141 # ifdef OPENSSL_INIT_DEBUG
142 fprintf(stderr, "OPENSSL_INIT: obtained DSO reference? %s\n",
143 (ret == TRUE ? "No!" : "Yes."));
145 return (ret == TRUE) ? 1 : 0;
149 * Deliberately leak a reference to ourselves. This will force the library
150 * to remain loaded until the atexit() handler is run at process exit.
156 if (!err_shelve_state(&err))
159 dso = DSO_dsobyaddr(&base_inited, DSO_FLAG_NO_UNLOAD_ON_FREE);
160 # ifdef OPENSSL_INIT_DEBUG
161 fprintf(stderr, "OPENSSL_INIT: obtained DSO reference? %s\n",
162 (dso == NULL ? "No!" : "Yes."));
164 * In case of No!, it is uncertain our exit()-handlers can still be
165 * called. After dlclose() the whole library might have been unloaded
170 err_unshelve_state(err);
178 static CRYPTO_ONCE load_crypto_strings = CRYPTO_ONCE_STATIC_INIT;
179 static int load_crypto_strings_inited = 0;
180 DEFINE_RUN_ONCE_STATIC(ossl_init_no_load_crypto_strings)
182 /* Do nothing in this case */
186 DEFINE_RUN_ONCE_STATIC(ossl_init_load_crypto_strings)
190 * OPENSSL_NO_AUTOERRINIT is provided here to prevent at compile time
191 * pulling in all the error strings during static linking
193 #if !defined(OPENSSL_NO_ERR) && !defined(OPENSSL_NO_AUTOERRINIT)
194 # ifdef OPENSSL_INIT_DEBUG
195 fprintf(stderr, "OPENSSL_INIT: ossl_init_load_crypto_strings: "
196 "err_load_crypto_strings_int()\n");
198 ret = err_load_crypto_strings_int();
199 load_crypto_strings_inited = 1;
204 static CRYPTO_ONCE add_all_ciphers = CRYPTO_ONCE_STATIC_INIT;
205 DEFINE_RUN_ONCE_STATIC(ossl_init_add_all_ciphers)
208 * OPENSSL_NO_AUTOALGINIT is provided here to prevent at compile time
209 * pulling in all the ciphers during static linking
211 #ifndef OPENSSL_NO_AUTOALGINIT
212 # ifdef OPENSSL_INIT_DEBUG
213 fprintf(stderr, "OPENSSL_INIT: ossl_init_add_all_ciphers: "
214 "openssl_add_all_ciphers_int()\n");
216 openssl_add_all_ciphers_int();
221 static CRYPTO_ONCE add_all_digests = CRYPTO_ONCE_STATIC_INIT;
222 DEFINE_RUN_ONCE_STATIC(ossl_init_add_all_digests)
225 * OPENSSL_NO_AUTOALGINIT is provided here to prevent at compile time
226 * pulling in all the ciphers during static linking
228 #ifndef OPENSSL_NO_AUTOALGINIT
229 # ifdef OPENSSL_INIT_DEBUG
230 fprintf(stderr, "OPENSSL_INIT: ossl_init_add_all_digests: "
231 "openssl_add_all_digests()\n");
233 openssl_add_all_digests_int();
238 DEFINE_RUN_ONCE_STATIC(ossl_init_no_add_algs)
244 static CRYPTO_ONCE config = CRYPTO_ONCE_STATIC_INIT;
245 static int config_inited = 0;
246 static const char *appname;
247 DEFINE_RUN_ONCE_STATIC(ossl_init_config)
249 #ifdef OPENSSL_INIT_DEBUG
251 "OPENSSL_INIT: ossl_init_config: openssl_config(%s)\n",
252 appname == NULL ? "NULL" : appname);
254 openssl_config_int(appname);
258 DEFINE_RUN_ONCE_STATIC(ossl_init_no_config)
260 #ifdef OPENSSL_INIT_DEBUG
262 "OPENSSL_INIT: ossl_init_config: openssl_no_config_int()\n");
264 openssl_no_config_int();
269 static CRYPTO_ONCE async = CRYPTO_ONCE_STATIC_INIT;
270 static int async_inited = 0;
271 DEFINE_RUN_ONCE_STATIC(ossl_init_async)
273 #ifdef OPENSSL_INIT_DEBUG
274 fprintf(stderr, "OPENSSL_INIT: ossl_init_async: async_init()\n");
282 #ifndef OPENSSL_NO_ENGINE
283 static CRYPTO_ONCE engine_openssl = CRYPTO_ONCE_STATIC_INIT;
284 DEFINE_RUN_ONCE_STATIC(ossl_init_engine_openssl)
286 # ifdef OPENSSL_INIT_DEBUG
287 fprintf(stderr, "OPENSSL_INIT: ossl_init_engine_openssl: "
288 "engine_load_openssl_int()\n");
290 engine_load_openssl_int();
293 # ifndef OPENSSL_NO_DEVCRYPTOENG
294 static CRYPTO_ONCE engine_devcrypto = CRYPTO_ONCE_STATIC_INIT;
295 DEFINE_RUN_ONCE_STATIC(ossl_init_engine_devcrypto)
297 # ifdef OPENSSL_INIT_DEBUG
298 fprintf(stderr, "OPENSSL_INIT: ossl_init_engine_devcrypto: "
299 "engine_load_devcrypto_int()\n");
301 engine_load_devcrypto_int();
306 # ifndef OPENSSL_NO_RDRAND
307 static CRYPTO_ONCE engine_rdrand = CRYPTO_ONCE_STATIC_INIT;
308 DEFINE_RUN_ONCE_STATIC(ossl_init_engine_rdrand)
310 # ifdef OPENSSL_INIT_DEBUG
311 fprintf(stderr, "OPENSSL_INIT: ossl_init_engine_rdrand: "
312 "engine_load_rdrand_int()\n");
314 engine_load_rdrand_int();
318 static CRYPTO_ONCE engine_dynamic = CRYPTO_ONCE_STATIC_INIT;
319 DEFINE_RUN_ONCE_STATIC(ossl_init_engine_dynamic)
321 # ifdef OPENSSL_INIT_DEBUG
322 fprintf(stderr, "OPENSSL_INIT: ossl_init_engine_dynamic: "
323 "engine_load_dynamic_int()\n");
325 engine_load_dynamic_int();
328 # ifndef OPENSSL_NO_STATIC_ENGINE
329 # if !defined(OPENSSL_NO_HW) && !defined(OPENSSL_NO_HW_PADLOCK)
330 static CRYPTO_ONCE engine_padlock = CRYPTO_ONCE_STATIC_INIT;
331 DEFINE_RUN_ONCE_STATIC(ossl_init_engine_padlock)
333 # ifdef OPENSSL_INIT_DEBUG
334 fprintf(stderr, "OPENSSL_INIT: ossl_init_engine_padlock: "
335 "engine_load_padlock_int()\n");
337 engine_load_padlock_int();
341 # if defined(OPENSSL_SYS_WIN32) && !defined(OPENSSL_NO_CAPIENG)
342 static CRYPTO_ONCE engine_capi = CRYPTO_ONCE_STATIC_INIT;
343 DEFINE_RUN_ONCE_STATIC(ossl_init_engine_capi)
345 # ifdef OPENSSL_INIT_DEBUG
346 fprintf(stderr, "OPENSSL_INIT: ossl_init_engine_capi: "
347 "engine_load_capi_int()\n");
349 engine_load_capi_int();
353 # if !defined(OPENSSL_NO_AFALGENG)
354 static CRYPTO_ONCE engine_afalg = CRYPTO_ONCE_STATIC_INIT;
355 DEFINE_RUN_ONCE_STATIC(ossl_init_engine_afalg)
357 # ifdef OPENSSL_INIT_DEBUG
358 fprintf(stderr, "OPENSSL_INIT: ossl_init_engine_afalg: "
359 "engine_load_afalg_int()\n");
361 engine_load_afalg_int();
368 #ifndef OPENSSL_NO_COMP
369 static CRYPTO_ONCE zlib = CRYPTO_ONCE_STATIC_INIT;
371 static int zlib_inited = 0;
372 DEFINE_RUN_ONCE_STATIC(ossl_init_zlib)
374 /* Do nothing - we need to know about this for the later cleanup */
380 static void ossl_init_thread_stop(struct thread_local_inits_st *locals)
382 /* Can't do much about this */
387 #ifdef OPENSSL_INIT_DEBUG
388 fprintf(stderr, "OPENSSL_INIT: ossl_init_thread_stop: "
389 "async_delete_thread_state()\n");
391 async_delete_thread_state();
394 if (locals->err_state) {
395 #ifdef OPENSSL_INIT_DEBUG
396 fprintf(stderr, "OPENSSL_INIT: ossl_init_thread_stop: "
397 "err_delete_thread_state()\n");
399 err_delete_thread_state();
403 #ifdef OPENSSL_INIT_DEBUG
404 fprintf(stderr, "OPENSSL_INIT: ossl_init_thread_stop: "
405 "drbg_delete_thread_state()\n");
407 drbg_delete_thread_state();
410 OPENSSL_free(locals);
413 void OPENSSL_thread_stop(void)
415 if (destructor_key.sane != -1)
416 ossl_init_thread_stop(ossl_init_get_thread_local(0));
419 int ossl_init_thread_start(uint64_t opts)
421 struct thread_local_inits_st *locals;
423 if (!OPENSSL_init_crypto(0, NULL))
426 locals = ossl_init_get_thread_local(1);
431 if (opts & OPENSSL_INIT_THREAD_ASYNC) {
432 #ifdef OPENSSL_INIT_DEBUG
433 fprintf(stderr, "OPENSSL_INIT: ossl_init_thread_start: "
434 "marking thread for async\n");
439 if (opts & OPENSSL_INIT_THREAD_ERR_STATE) {
440 #ifdef OPENSSL_INIT_DEBUG
441 fprintf(stderr, "OPENSSL_INIT: ossl_init_thread_start: "
442 "marking thread for err_state\n");
444 locals->err_state = 1;
447 if (opts & OPENSSL_INIT_THREAD_RAND) {
448 #ifdef OPENSSL_INIT_DEBUG
449 fprintf(stderr, "OPENSSL_INIT: ossl_init_thread_start: "
450 "marking thread for rand\n");
458 void OPENSSL_cleanup(void)
460 OPENSSL_INIT_STOP *currhandler, *lasthandler;
461 CRYPTO_THREAD_LOCAL key;
463 /* If we've not been inited then no need to deinit */
467 /* Might be explicitly called and also by atexit */
473 * Thread stop may not get automatically called by the thread library for
474 * the very last thread in some situations, so call it directly.
476 ossl_init_thread_stop(ossl_init_get_thread_local(0));
478 currhandler = stop_handlers;
479 while (currhandler != NULL) {
480 currhandler->handler();
481 lasthandler = currhandler;
482 currhandler = currhandler->next;
483 OPENSSL_free(lasthandler);
485 stop_handlers = NULL;
487 CRYPTO_THREAD_lock_free(init_lock);
491 * We assume we are single-threaded for this function, i.e. no race
492 * conditions for the various "*_inited" vars below.
495 #ifndef OPENSSL_NO_COMP
497 #ifdef OPENSSL_INIT_DEBUG
498 fprintf(stderr, "OPENSSL_INIT: OPENSSL_cleanup: "
499 "comp_zlib_cleanup_int()\n");
501 comp_zlib_cleanup_int();
506 # ifdef OPENSSL_INIT_DEBUG
507 fprintf(stderr, "OPENSSL_INIT: OPENSSL_cleanup: "
513 if (load_crypto_strings_inited) {
514 #ifdef OPENSSL_INIT_DEBUG
515 fprintf(stderr, "OPENSSL_INIT: OPENSSL_cleanup: "
516 "err_free_strings_int()\n");
518 err_free_strings_int();
521 key = destructor_key.value;
522 destructor_key.sane = -1;
523 CRYPTO_THREAD_cleanup_local(&key);
525 #ifdef OPENSSL_INIT_DEBUG
526 fprintf(stderr, "OPENSSL_INIT: OPENSSL_cleanup: "
527 "rand_cleanup_int()\n");
528 fprintf(stderr, "OPENSSL_INIT: OPENSSL_cleanup: "
529 "conf_modules_free_int()\n");
530 #ifndef OPENSSL_NO_ENGINE
531 fprintf(stderr, "OPENSSL_INIT: OPENSSL_cleanup: "
532 "engine_cleanup_int()\n");
534 fprintf(stderr, "OPENSSL_INIT: OPENSSL_cleanup: "
535 "crypto_cleanup_all_ex_data_int()\n");
536 fprintf(stderr, "OPENSSL_INIT: OPENSSL_cleanup: "
537 "bio_sock_cleanup_int()\n");
538 fprintf(stderr, "OPENSSL_INIT: OPENSSL_cleanup: "
540 fprintf(stderr, "OPENSSL_INIT: OPENSSL_cleanup: "
541 "evp_cleanup_int()\n");
542 fprintf(stderr, "OPENSSL_INIT: OPENSSL_cleanup: "
543 "obj_cleanup_int()\n");
544 fprintf(stderr, "OPENSSL_INIT: OPENSSL_cleanup: "
548 * Note that cleanup order is important:
549 * - rand_cleanup_int could call an ENGINE's RAND cleanup function so
550 * must be called before engine_cleanup_int()
551 * - ENGINEs use CRYPTO_EX_DATA and therefore, must be cleaned up
552 * before the ex data handlers are wiped in CRYPTO_cleanup_all_ex_data().
553 * - conf_modules_free_int() can end up in ENGINE code so must be called
554 * before engine_cleanup_int()
555 * - ENGINEs and additional EVP algorithms might use added OIDs names so
556 * obj_cleanup_int() must be called last
559 rand_drbg_cleanup_int();
560 conf_modules_free_int();
561 #ifndef OPENSSL_NO_ENGINE
562 engine_cleanup_int();
564 ossl_store_cleanup_int();
565 crypto_cleanup_all_ex_data_int();
571 CRYPTO_secure_malloc_done();
577 * If this function is called with a non NULL settings value then it must be
578 * called prior to any threads making calls to any OpenSSL functions,
579 * i.e. passing a non-null settings value is assumed to be single-threaded.
581 int OPENSSL_init_crypto(uint64_t opts, const OPENSSL_INIT_SETTINGS *settings)
584 if (!(opts & OPENSSL_INIT_BASE_ONLY))
585 CRYPTOerr(CRYPTO_F_OPENSSL_INIT_CRYPTO, ERR_R_INIT_FAIL);
589 if (!RUN_ONCE(&base, ossl_init_base))
592 if (!(opts & OPENSSL_INIT_BASE_ONLY)
593 && !RUN_ONCE(&load_crypto_nodelete,
594 ossl_init_load_crypto_nodelete))
597 if ((opts & OPENSSL_INIT_NO_LOAD_CRYPTO_STRINGS)
598 && !RUN_ONCE(&load_crypto_strings,
599 ossl_init_no_load_crypto_strings))
602 if ((opts & OPENSSL_INIT_LOAD_CRYPTO_STRINGS)
603 && !RUN_ONCE(&load_crypto_strings, ossl_init_load_crypto_strings))
606 if ((opts & OPENSSL_INIT_NO_ADD_ALL_CIPHERS)
607 && !RUN_ONCE(&add_all_ciphers, ossl_init_no_add_algs))
610 if ((opts & OPENSSL_INIT_ADD_ALL_CIPHERS)
611 && !RUN_ONCE(&add_all_ciphers, ossl_init_add_all_ciphers))
614 if ((opts & OPENSSL_INIT_NO_ADD_ALL_DIGESTS)
615 && !RUN_ONCE(&add_all_digests, ossl_init_no_add_algs))
618 if ((opts & OPENSSL_INIT_ADD_ALL_DIGESTS)
619 && !RUN_ONCE(&add_all_digests, ossl_init_add_all_digests))
622 if ((opts & OPENSSL_INIT_ATFORK)
623 && !openssl_init_fork_handlers())
626 if ((opts & OPENSSL_INIT_NO_LOAD_CONFIG)
627 && !RUN_ONCE(&config, ossl_init_no_config))
630 if (opts & OPENSSL_INIT_LOAD_CONFIG) {
632 CRYPTO_THREAD_write_lock(init_lock);
633 appname = (settings == NULL) ? NULL : settings->appname;
634 ret = RUN_ONCE(&config, ossl_init_config);
635 CRYPTO_THREAD_unlock(init_lock);
640 if ((opts & OPENSSL_INIT_ASYNC)
641 && !RUN_ONCE(&async, ossl_init_async))
644 #ifndef OPENSSL_NO_ENGINE
645 if ((opts & OPENSSL_INIT_ENGINE_OPENSSL)
646 && !RUN_ONCE(&engine_openssl, ossl_init_engine_openssl))
648 # if !defined(OPENSSL_NO_HW) && !defined(OPENSSL_NO_DEVCRYPTOENG)
649 if ((opts & OPENSSL_INIT_ENGINE_CRYPTODEV)
650 && !RUN_ONCE(&engine_devcrypto, ossl_init_engine_devcrypto))
653 # ifndef OPENSSL_NO_RDRAND
654 if ((opts & OPENSSL_INIT_ENGINE_RDRAND)
655 && !RUN_ONCE(&engine_rdrand, ossl_init_engine_rdrand))
658 if ((opts & OPENSSL_INIT_ENGINE_DYNAMIC)
659 && !RUN_ONCE(&engine_dynamic, ossl_init_engine_dynamic))
661 # ifndef OPENSSL_NO_STATIC_ENGINE
662 # if !defined(OPENSSL_NO_HW) && !defined(OPENSSL_NO_HW_PADLOCK)
663 if ((opts & OPENSSL_INIT_ENGINE_PADLOCK)
664 && !RUN_ONCE(&engine_padlock, ossl_init_engine_padlock))
667 # if defined(OPENSSL_SYS_WIN32) && !defined(OPENSSL_NO_CAPIENG)
668 if ((opts & OPENSSL_INIT_ENGINE_CAPI)
669 && !RUN_ONCE(&engine_capi, ossl_init_engine_capi))
672 # if !defined(OPENSSL_NO_AFALGENG)
673 if ((opts & OPENSSL_INIT_ENGINE_AFALG)
674 && !RUN_ONCE(&engine_afalg, ossl_init_engine_afalg))
678 if (opts & (OPENSSL_INIT_ENGINE_ALL_BUILTIN
679 | OPENSSL_INIT_ENGINE_OPENSSL
680 | OPENSSL_INIT_ENGINE_AFALG)) {
681 ENGINE_register_all_complete();
685 #ifndef OPENSSL_NO_COMP
686 if ((opts & OPENSSL_INIT_ZLIB)
687 && !RUN_ONCE(&zlib, ossl_init_zlib))
694 int OPENSSL_atexit(void (*handler)(void))
696 OPENSSL_INIT_STOP *newhand;
698 #if !defined(OPENSSL_NO_DSO) && !defined(OPENSSL_USE_NODELETE)
705 handlersym.func = handler;
708 HMODULE handle = NULL;
712 * We don't use the DSO route for WIN32 because there is a better
715 ret = GetModuleHandleEx(GET_MODULE_HANDLE_EX_FLAG_FROM_ADDRESS
716 | GET_MODULE_HANDLE_EX_FLAG_PIN,
717 handlersym.sym, &handle);
724 * Deliberately leak a reference to the handler. This will force the
725 * library/code containing the handler to remain loaded until we run the
726 * atexit handler. If -znodelete has been used then this is
733 dso = DSO_dsobyaddr(handlersym.sym, DSO_FLAG_NO_UNLOAD_ON_FREE);
734 # ifdef OPENSSL_INIT_DEBUG
736 "OPENSSL_INIT: OPENSSL_atexit: obtained DSO reference? %s\n",
737 (dso == NULL ? "No!" : "Yes."));
738 /* See same code above in ossl_init_base() for an explanation. */
747 if ((newhand = OPENSSL_malloc(sizeof(*newhand))) == NULL) {
748 CRYPTOerr(CRYPTO_F_OPENSSL_ATEXIT, ERR_R_MALLOC_FAILURE);
752 newhand->handler = handler;
753 newhand->next = stop_handlers;
754 stop_handlers = newhand;
759 #ifdef OPENSSL_SYS_UNIX
761 * The following three functions are for OpenSSL developers. This is
762 * where we set/reset state across fork (called via pthread_atfork when
763 * it exists, or manually by the application when it doesn't).
765 * WARNING! If you put code in either OPENSSL_fork_parent or
766 * OPENSSL_fork_child, you MUST MAKE SURE that they are async-signal-
767 * safe. See this link, for example:
768 * http://man7.org/linux/man-pages/man7/signal-safety.7.html
771 void OPENSSL_fork_prepare(void)
775 void OPENSSL_fork_parent(void)
779 void OPENSSL_fork_child(void)