crypto/init.c

   1 /*
   2  * Copyright 2016-2018 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 #include "e_os.h"
  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"
  24 #include <stdlib.h>
  25 #include <assert.h>
  26 #include "internal/thread_once.h"
  27 #include "internal/dso_conf.h"
  28 #include "internal/dso.h"
  29 #include "internal/store.h"
  30 #include <openssl/cmp_util.h> /* for OSSL_CMP_log_close() */
  31 #include <openssl/trace.h>
  32
  33 static int stopped = 0;
  34
  35 typedef struct ossl_init_stop_st OPENSSL_INIT_STOP;
  36 struct ossl_init_stop_st {
  37     void (*handler)(void);
  38     OPENSSL_INIT_STOP *next;
  39 };
  40
  41 static OPENSSL_INIT_STOP *stop_handlers = NULL;
  42 static CRYPTO_RWLOCK *init_lock = NULL;
  43
  44 static CRYPTO_ONCE base = CRYPTO_ONCE_STATIC_INIT;
  45 static int base_inited = 0;
  46 DEFINE_RUN_ONCE_STATIC(ossl_init_base)
  47 {
  48     /* no need to init trace */
  49
  50     OSSL_TRACE(INIT, "ossl_init_base: setting up stop handlers\n");
  51 #ifndef OPENSSL_NO_CRYPTO_MDEBUG
  52     ossl_malloc_setup_failures();
  53 #endif
  54
  55     if ((init_lock = CRYPTO_THREAD_lock_new()) == NULL)
  56         goto err;
  57     OPENSSL_cpuid_setup();
  58
  59     if (!ossl_init_thread())
  60         return 0;
  61
  62     base_inited = 1;
  63     return 1;
  64
  65 err:
  66     OSSL_TRACE(INIT, "ossl_init_base failed!\n");
  67     CRYPTO_THREAD_lock_free(init_lock);
  68     init_lock = NULL;
  69
  70     return 0;
  71 }
  72
  73 static CRYPTO_ONCE register_atexit = CRYPTO_ONCE_STATIC_INIT;
  74 #if !defined(OPENSSL_SYS_UEFI) && defined(_WIN32)
  75 static int win32atexit(void)
  76 {
  77     OPENSSL_cleanup();
  78     return 0;
  79 }
  80 #endif
  81
  82 DEFINE_RUN_ONCE_STATIC(ossl_init_register_atexit)
  83 {
  84 #ifdef OPENSSL_INIT_DEBUG
  85     fprintf(stderr, "OPENSSL_INIT: ossl_init_register_atexit()\n");
  86 #endif
  87 #ifndef OPENSSL_SYS_UEFI
  88 # ifdef _WIN32
  89     /* We use _onexit() in preference because it gets called on DLL unload */
  90     if (_onexit(win32atexit) == NULL)
  91         return 0;
  92 # else
  93     if (atexit(OPENSSL_cleanup) != 0)
  94         return 0;
  95 # endif
  96 #endif
  97
  98     return 1;
  99 }
 100
 101 DEFINE_RUN_ONCE_STATIC_ALT(ossl_init_no_register_atexit,
 102                            ossl_init_register_atexit)
 103 {
 104 #ifdef OPENSSL_INIT_DEBUG
 105     fprintf(stderr, "OPENSSL_INIT: ossl_init_no_register_atexit ok!\n");
 106 #endif
 107     /* Do nothing in this case */
 108     return 1;
 109 }
 110
 111 static CRYPTO_ONCE load_crypto_nodelete = CRYPTO_ONCE_STATIC_INIT;
 112 DEFINE_RUN_ONCE_STATIC(ossl_init_load_crypto_nodelete)
 113 {
 114     OSSL_TRACE(INIT, "ossl_init_load_crypto_nodelete()\n");
 115
 116 #if !defined(OPENSSL_USE_NODELETE) \
 117     && !defined(OPENSSL_NO_PINSHARED)
 118 # if defined(DSO_WIN32) && !defined(_WIN32_WCE)
 119     {
 120         HMODULE handle = NULL;
 121         BOOL ret;
 122
 123         /* We don't use the DSO route for WIN32 because there is a better way */
 124         ret = GetModuleHandleEx(GET_MODULE_HANDLE_EX_FLAG_FROM_ADDRESS
 125                                 | GET_MODULE_HANDLE_EX_FLAG_PIN,
 126                                 (void *)&base_inited, &handle);
 127
 128         OSSL_TRACE1(INIT,
 129                     "ossl_init_load_crypto_nodelete: "
 130                     "obtained DSO reference? %s\n",
 131                     (ret == TRUE ? "No!" : "Yes."));
 132         return (ret == TRUE) ? 1 : 0;
 133     }
 134 # elif !defined(DSO_NONE)
 135     /*
 136      * Deliberately leak a reference to ourselves. This will force the library
 137      * to remain loaded until the atexit() handler is run at process exit.
 138      */
 139     {
 140         DSO *dso;
 141         void *err;
 142
 143         if (!err_shelve_state(&err))
 144             return 0;
 145
 146         dso = DSO_dsobyaddr(&base_inited, DSO_FLAG_NO_UNLOAD_ON_FREE);
 147         /*
 148          * In case of No!, it is uncertain our exit()-handlers can still be
 149          * called. After dlclose() the whole library might have been unloaded
 150          * already.
 151          */
 152         OSSL_TRACE1(INIT, "obtained DSO reference? %s\n",
 153                     (dso == NULL ? "No!" : "Yes."));
 154         DSO_free(dso);
 155         err_unshelve_state(err);
 156     }
 157 # endif
 158 #endif
 159
 160     return 1;
 161 }
 162
 163 static CRYPTO_ONCE load_crypto_strings = CRYPTO_ONCE_STATIC_INIT;
 164 static int load_crypto_strings_inited = 0;
 165 DEFINE_RUN_ONCE_STATIC(ossl_init_load_crypto_strings)
 166 {
 167     int ret = 1;
 168     /*
 169      * OPENSSL_NO_AUTOERRINIT is provided here to prevent at compile time
 170      * pulling in all the error strings during static linking
 171      */
 172 #if !defined(OPENSSL_NO_ERR) && !defined(OPENSSL_NO_AUTOERRINIT)
 173     OSSL_TRACE(INIT, "err_load_crypto_strings_int()\n");
 174     ret = err_load_crypto_strings_int();
 175     load_crypto_strings_inited = 1;
 176 #endif
 177     return ret;
 178 }
 179
 180 DEFINE_RUN_ONCE_STATIC_ALT(ossl_init_no_load_crypto_strings,
 181                            ossl_init_load_crypto_strings)
 182 {
 183     /* Do nothing in this case */
 184     return 1;
 185 }
 186
 187 static CRYPTO_ONCE add_all_ciphers = CRYPTO_ONCE_STATIC_INIT;
 188 DEFINE_RUN_ONCE_STATIC(ossl_init_add_all_ciphers)
 189 {
 190     /*
 191      * OPENSSL_NO_AUTOALGINIT is provided here to prevent at compile time
 192      * pulling in all the ciphers during static linking
 193      */
 194 #ifndef OPENSSL_NO_AUTOALGINIT
 195     OSSL_TRACE(INIT, "openssl_add_all_ciphers_int()\n");
 196     openssl_add_all_ciphers_int();
 197 #endif
 198     return 1;
 199 }
 200
 201 DEFINE_RUN_ONCE_STATIC_ALT(ossl_init_no_add_all_ciphers,
 202                            ossl_init_add_all_ciphers)
 203 {
 204     /* Do nothing */
 205     return 1;
 206 }
 207
 208 static CRYPTO_ONCE add_all_digests = CRYPTO_ONCE_STATIC_INIT;
 209 DEFINE_RUN_ONCE_STATIC(ossl_init_add_all_digests)
 210 {
 211     /*
 212      * OPENSSL_NO_AUTOALGINIT is provided here to prevent at compile time
 213      * pulling in all the ciphers during static linking
 214      */
 215 #ifndef OPENSSL_NO_AUTOALGINIT
 216     OSSL_TRACE(INIT, "openssl_add_all_digests()\n");
 217     openssl_add_all_digests_int();
 218 #endif
 219     return 1;
 220 }
 221
 222 DEFINE_RUN_ONCE_STATIC_ALT(ossl_init_no_add_all_digests,
 223                            ossl_init_add_all_digests)
 224 {
 225     /* Do nothing */
 226     return 1;
 227 }
 228
 229 static CRYPTO_ONCE config = CRYPTO_ONCE_STATIC_INIT;
 230 static int config_inited = 0;
 231 static const OPENSSL_INIT_SETTINGS *conf_settings = NULL;
 232 DEFINE_RUN_ONCE_STATIC(ossl_init_config)
 233 {
 234     int ret = openssl_config_int(conf_settings);
 235     config_inited = 1;
 236     return ret;
 237 }
 238 DEFINE_RUN_ONCE_STATIC_ALT(ossl_init_no_config, ossl_init_config)
 239 {
 240     OSSL_TRACE(INIT, "openssl_no_config_int()\n");
 241     openssl_no_config_int();
 242     config_inited = 1;
 243     return 1;
 244 }
 245
 246 static CRYPTO_ONCE async = CRYPTO_ONCE_STATIC_INIT;
 247 static int async_inited = 0;
 248 DEFINE_RUN_ONCE_STATIC(ossl_init_async)
 249 {
 250     OSSL_TRACE(INIT, "async_init()\n");
 251     if (!async_init())
 252         return 0;
 253     async_inited = 1;
 254     return 1;
 255 }
 256
 257 #ifndef OPENSSL_NO_ENGINE
 258 static CRYPTO_ONCE engine_openssl = CRYPTO_ONCE_STATIC_INIT;
 259 DEFINE_RUN_ONCE_STATIC(ossl_init_engine_openssl)
 260 {
 261     OSSL_TRACE(INIT, "engine_load_openssl_int()\n");
 262     engine_load_openssl_int();
 263     return 1;
 264 }
 265 # ifndef OPENSSL_NO_RDRAND
 266 static CRYPTO_ONCE engine_rdrand = CRYPTO_ONCE_STATIC_INIT;
 267 DEFINE_RUN_ONCE_STATIC(ossl_init_engine_rdrand)
 268 {
 269     OSSL_TRACE(INIT, "engine_load_rdrand_int()\n");
 270     engine_load_rdrand_int();
 271     return 1;
 272 }
 273 # endif
 274 static CRYPTO_ONCE engine_dynamic = CRYPTO_ONCE_STATIC_INIT;
 275 DEFINE_RUN_ONCE_STATIC(ossl_init_engine_dynamic)
 276 {
 277     OSSL_TRACE(INIT, "engine_load_dynamic_int()\n");
 278     engine_load_dynamic_int();
 279     return 1;
 280 }
 281 # ifndef OPENSSL_NO_STATIC_ENGINE
 282 #  ifndef OPENSSL_NO_DEVCRYPTOENG
 283 static CRYPTO_ONCE engine_devcrypto = CRYPTO_ONCE_STATIC_INIT;
 284 DEFINE_RUN_ONCE_STATIC(ossl_init_engine_devcrypto)
 285 {
 286     OSSL_TRACE(INIT, "engine_load_devcrypto_int()\n");
 287     engine_load_devcrypto_int();
 288     return 1;
 289 }
 290 #  endif
 291 #  if !defined(OPENSSL_NO_PADLOCKENG)
 292 static CRYPTO_ONCE engine_padlock = CRYPTO_ONCE_STATIC_INIT;
 293 DEFINE_RUN_ONCE_STATIC(ossl_init_engine_padlock)
 294 {
 295     OSSL_TRACE(INIT, "engine_load_padlock_int()\n");
 296     engine_load_padlock_int();
 297     return 1;
 298 }
 299 #  endif
 300 #  if defined(OPENSSL_SYS_WIN32) && !defined(OPENSSL_NO_CAPIENG)
 301 static CRYPTO_ONCE engine_capi = CRYPTO_ONCE_STATIC_INIT;
 302 DEFINE_RUN_ONCE_STATIC(ossl_init_engine_capi)
 303 {
 304     OSSL_TRACE(INIT, "engine_load_capi_int()\n");
 305     engine_load_capi_int();
 306     return 1;
 307 }
 308 #  endif
 309 #  if !defined(OPENSSL_NO_AFALGENG)
 310 static CRYPTO_ONCE engine_afalg = CRYPTO_ONCE_STATIC_INIT;
 311 DEFINE_RUN_ONCE_STATIC(ossl_init_engine_afalg)
 312 {
 313     OSSL_TRACE(INIT, "engine_load_afalg_int()\n");
 314     engine_load_afalg_int();
 315     return 1;
 316 }
 317 #  endif
 318 # endif
 319 #endif
 320
 321 #ifndef OPENSSL_NO_COMP
 322 static CRYPTO_ONCE zlib = CRYPTO_ONCE_STATIC_INIT;
 323
 324 static int zlib_inited = 0;
 325 DEFINE_RUN_ONCE_STATIC(ossl_init_zlib)
 326 {
 327     /* Do nothing - we need to know about this for the later cleanup */
 328     zlib_inited = 1;
 329     return 1;
 330 }
 331 #endif
 332
 333 void OPENSSL_cleanup(void)
 334 {
 335     OPENSSL_INIT_STOP *currhandler, *lasthandler;
 336
 337     /*
 338      * TODO(3.0): This function needs looking at with a view to moving most/all
 339      * of this into onfree handlers in OPENSSL_CTX.
 340      */
 341
 342     /* If we've not been inited then no need to deinit */
 343     if (!base_inited)
 344         return;
 345
 346     /* Might be explicitly called and also by atexit */
 347     if (stopped)
 348         return;
 349     stopped = 1;
 350
 351     /*
 352      * Thread stop may not get automatically called by the thread library for
 353      * the very last thread in some situations, so call it directly.
 354      */
 355     OPENSSL_thread_stop();
 356
 357     currhandler = stop_handlers;
 358     while (currhandler != NULL) {
 359         currhandler->handler();
 360         lasthandler = currhandler;
 361         currhandler = currhandler->next;
 362         OPENSSL_free(lasthandler);
 363     }
 364     stop_handlers = NULL;
 365
 366     CRYPTO_THREAD_lock_free(init_lock);
 367     init_lock = NULL;
 368
 369     /*
 370      * We assume we are single-threaded for this function, i.e. no race
 371      * conditions for the various "*_inited" vars below.
 372      */
 373
 374 #ifndef OPENSSL_NO_COMP
 375     if (zlib_inited) {
 376         OSSL_TRACE(INIT, "OPENSSL_cleanup: comp_zlib_cleanup_int()\n");
 377         comp_zlib_cleanup_int();
 378     }
 379 #endif
 380
 381     if (async_inited) {
 382         OSSL_TRACE(INIT, "OPENSSL_cleanup: async_deinit()\n");
 383         async_deinit();
 384     }
 385
 386     if (load_crypto_strings_inited) {
 387         OSSL_TRACE(INIT, "OPENSSL_cleanup: err_free_strings_int()\n");
 388         err_free_strings_int();
 389     }
 390
 391     /*
 392      * Note that cleanup order is important:
 393      * - rand_cleanup_int could call an ENGINE's RAND cleanup function so
 394      * must be called before engine_cleanup_int()
 395      * - ENGINEs use CRYPTO_EX_DATA and therefore, must be cleaned up
 396      * before the ex data handlers are wiped during default openssl_ctx deinit.
 397      * - conf_modules_free_int() can end up in ENGINE code so must be called
 398      * before engine_cleanup_int()
 399      * - ENGINEs and additional EVP algorithms might use added OIDs names so
 400      * obj_cleanup_int() must be called last
 401      */
 402     OSSL_TRACE(INIT, "OPENSSL_cleanup: rand_cleanup_int()\n");
 403     rand_cleanup_int();
 404
 405     OSSL_TRACE(INIT, "OPENSSL_cleanup: conf_modules_free_int()\n");
 406     conf_modules_free_int();
 407
 408 #ifndef OPENSSL_NO_ENGINE
 409     OSSL_TRACE(INIT, "OPENSSL_cleanup: engine_cleanup_int()\n");
 410     engine_cleanup_int();
 411 #endif
 412     OSSL_TRACE(INIT, "OPENSSL_cleanup: ossl_store_cleanup_int()\n");
 413     ossl_store_cleanup_int();
 414
 415     OSSL_TRACE(INIT, "OPENSSL_cleanup: openssl_ctx_default_deinit()\n");
 416     openssl_ctx_default_deinit();
 417
 418     ossl_cleanup_thread();
 419
 420     OSSL_TRACE(INIT, "OPENSSL_cleanup: bio_cleanup()\n");
 421     bio_cleanup();
 422
 423     OSSL_TRACE(INIT, "OPENSSL_cleanup: evp_cleanup_int()\n");
 424     evp_cleanup_int();
 425
 426     OSSL_TRACE(INIT, "OPENSSL_cleanup: obj_cleanup_int()\n");
 427     obj_cleanup_int();
 428
 429     OSSL_TRACE(INIT, "OPENSSL_cleanup: err_int()\n");
 430     err_cleanup();
 431
 432     OSSL_TRACE(INIT, "OPENSSL_cleanup: CRYPTO_secure_malloc_done()\n");
 433     CRYPTO_secure_malloc_done();
 434
 435 #ifndef OPENSSL_NO_CMP
 436     OSSL_TRACE(INIT, "OPENSSL_cleanup: OSSL_CMP_log_close()\n");
 437     OSSL_CMP_log_close();
 438 #endif
 439
 440     OSSL_TRACE(INIT, "OPENSSL_cleanup: ossl_trace_cleanup()\n");
 441     ossl_trace_cleanup();
 442
 443     base_inited = 0;
 444 }
 445
 446 /*
 447  * If this function is called with a non NULL settings value then it must be
 448  * called prior to any threads making calls to any OpenSSL functions,
 449  * i.e. passing a non-null settings value is assumed to be single-threaded.
 450  */
 451 int OPENSSL_init_crypto(uint64_t opts, const OPENSSL_INIT_SETTINGS *settings)
 452 {
 453     /*
 454      * TODO(3.0): This function needs looking at with a view to moving most/all
 455      * of this into OPENSSL_CTX.
 456      */
 457
 458     if (stopped) {
 459         if (!(opts & OPENSSL_INIT_BASE_ONLY))
 460             CRYPTOerr(CRYPTO_F_OPENSSL_INIT_CRYPTO, ERR_R_INIT_FAIL);
 461         return 0;
 462     }
 463
 464     /*
 465      * When the caller specifies OPENSSL_INIT_BASE_ONLY, that should be the
 466      * *only* option specified.  With that option we return immediately after
 467      * doing the requested limited initialization.  Note that
 468      * err_shelve_state() called by us via ossl_init_load_crypto_nodelete()
 469      * re-enters OPENSSL_init_crypto() with OPENSSL_INIT_BASE_ONLY, but with
 470      * base already initialized this is a harmless NOOP.
 471      *
 472      * If we remain the only caller of err_shelve_state() the recursion should
 473      * perhaps be removed, but if in doubt, it can be left in place.
 474      */
 475     if (!RUN_ONCE(&base, ossl_init_base))
 476         return 0;
 477
 478     if (opts & OPENSSL_INIT_BASE_ONLY)
 479         return 1;
 480
 481     /*
 482      * Now we don't always set up exit handlers, the INIT_BASE_ONLY calls
 483      * should not have the side-effect of setting up exit handlers, and
 484      * therefore, this code block is below the INIT_BASE_ONLY-conditioned early
 485      * return above.
 486      */
 487     if ((opts & OPENSSL_INIT_NO_ATEXIT) != 0) {
 488         if (!RUN_ONCE_ALT(&register_atexit, ossl_init_no_register_atexit,
 489                           ossl_init_register_atexit))
 490             return 0;
 491     } else if (!RUN_ONCE(&register_atexit, ossl_init_register_atexit)) {
 492         return 0;
 493     }
 494
 495     if (!RUN_ONCE(&load_crypto_nodelete, ossl_init_load_crypto_nodelete))
 496         return 0;
 497
 498     if ((opts & OPENSSL_INIT_NO_LOAD_CRYPTO_STRINGS)
 499             && !RUN_ONCE_ALT(&load_crypto_strings,
 500                              ossl_init_no_load_crypto_strings,
 501                              ossl_init_load_crypto_strings))
 502         return 0;
 503
 504     if ((opts & OPENSSL_INIT_LOAD_CRYPTO_STRINGS)
 505             && !RUN_ONCE(&load_crypto_strings, ossl_init_load_crypto_strings))
 506         return 0;
 507
 508     if ((opts & OPENSSL_INIT_NO_ADD_ALL_CIPHERS)
 509             && !RUN_ONCE_ALT(&add_all_ciphers, ossl_init_no_add_all_ciphers,
 510                              ossl_init_add_all_ciphers))
 511         return 0;
 512
 513     if ((opts & OPENSSL_INIT_ADD_ALL_CIPHERS)
 514             && !RUN_ONCE(&add_all_ciphers, ossl_init_add_all_ciphers))
 515         return 0;
 516
 517     if ((opts & OPENSSL_INIT_NO_ADD_ALL_DIGESTS)
 518             && !RUN_ONCE_ALT(&add_all_digests, ossl_init_no_add_all_digests,
 519                              ossl_init_add_all_digests))
 520         return 0;
 521
 522     if ((opts & OPENSSL_INIT_ADD_ALL_DIGESTS)
 523             && !RUN_ONCE(&add_all_digests, ossl_init_add_all_digests))
 524         return 0;
 525
 526     if ((opts & OPENSSL_INIT_ATFORK)
 527             && !openssl_init_fork_handlers())
 528         return 0;
 529
 530     if ((opts & OPENSSL_INIT_NO_LOAD_CONFIG)
 531             && !RUN_ONCE_ALT(&config, ossl_init_no_config, ossl_init_config))
 532         return 0;
 533
 534     if (opts & OPENSSL_INIT_LOAD_CONFIG) {
 535         int ret;
 536         CRYPTO_THREAD_write_lock(init_lock);
 537         conf_settings = settings;
 538         ret = RUN_ONCE(&config, ossl_init_config);
 539         conf_settings = NULL;
 540         CRYPTO_THREAD_unlock(init_lock);
 541         if (ret <= 0)
 542             return 0;
 543     }
 544
 545     if ((opts & OPENSSL_INIT_ASYNC)
 546             && !RUN_ONCE(&async, ossl_init_async))
 547         return 0;
 548
 549 #ifndef OPENSSL_NO_ENGINE
 550     if ((opts & OPENSSL_INIT_ENGINE_OPENSSL)
 551             && !RUN_ONCE(&engine_openssl, ossl_init_engine_openssl))
 552         return 0;
 553 # ifndef OPENSSL_NO_RDRAND
 554     if ((opts & OPENSSL_INIT_ENGINE_RDRAND)
 555             && !RUN_ONCE(&engine_rdrand, ossl_init_engine_rdrand))
 556         return 0;
 557 # endif
 558     if ((opts & OPENSSL_INIT_ENGINE_DYNAMIC)
 559             && !RUN_ONCE(&engine_dynamic, ossl_init_engine_dynamic))
 560         return 0;
 561 # ifndef OPENSSL_NO_STATIC_ENGINE
 562 #  ifndef OPENSSL_NO_DEVCRYPTOENG
 563     if ((opts & OPENSSL_INIT_ENGINE_CRYPTODEV)
 564             && !RUN_ONCE(&engine_devcrypto, ossl_init_engine_devcrypto))
 565         return 0;
 566 #  endif
 567 #  if !defined(OPENSSL_NO_PADLOCKENG)
 568     if ((opts & OPENSSL_INIT_ENGINE_PADLOCK)
 569             && !RUN_ONCE(&engine_padlock, ossl_init_engine_padlock))
 570         return 0;
 571 #  endif
 572 #  if defined(OPENSSL_SYS_WIN32) && !defined(OPENSSL_NO_CAPIENG)
 573     if ((opts & OPENSSL_INIT_ENGINE_CAPI)
 574             && !RUN_ONCE(&engine_capi, ossl_init_engine_capi))
 575         return 0;
 576 #  endif
 577 #  if !defined(OPENSSL_NO_AFALGENG)
 578     if ((opts & OPENSSL_INIT_ENGINE_AFALG)
 579             && !RUN_ONCE(&engine_afalg, ossl_init_engine_afalg))
 580         return 0;
 581 #  endif
 582 # endif
 583     if (opts & (OPENSSL_INIT_ENGINE_ALL_BUILTIN
 584                 | OPENSSL_INIT_ENGINE_OPENSSL
 585                 | OPENSSL_INIT_ENGINE_AFALG)) {
 586         ENGINE_register_all_complete();
 587     }
 588 #endif
 589
 590 #ifndef OPENSSL_NO_COMP
 591     if ((opts & OPENSSL_INIT_ZLIB)
 592             && !RUN_ONCE(&zlib, ossl_init_zlib))
 593         return 0;
 594 #endif
 595
 596     return 1;
 597 }
 598
 599 int OPENSSL_atexit(void (*handler)(void))
 600 {
 601     OPENSSL_INIT_STOP *newhand;
 602
 603 #if !defined(OPENSSL_USE_NODELETE)\
 604     && !defined(OPENSSL_NO_PINSHARED)
 605     {
 606         union {
 607             void *sym;
 608             void (*func)(void);
 609         } handlersym;
 610
 611         handlersym.func = handler;
 612 # if defined(DSO_WIN32) && !defined(_WIN32_WCE)
 613         {
 614             HMODULE handle = NULL;
 615             BOOL ret;
 616
 617             /*
 618              * We don't use the DSO route for WIN32 because there is a better
 619              * way
 620              */
 621             ret = GetModuleHandleEx(GET_MODULE_HANDLE_EX_FLAG_FROM_ADDRESS
 622                                     | GET_MODULE_HANDLE_EX_FLAG_PIN,
 623                                     handlersym.sym, &handle);
 624
 625             if (!ret)
 626                 return 0;
 627         }
 628 # elif !defined(DSO_NONE)
 629         /*
 630          * Deliberately leak a reference to the handler. This will force the
 631          * library/code containing the handler to remain loaded until we run the
 632          * atexit handler. If -znodelete has been used then this is
 633          * unnecessary.
 634          */
 635         {
 636             DSO *dso = NULL;
 637
 638             ERR_set_mark();
 639             dso = DSO_dsobyaddr(handlersym.sym, DSO_FLAG_NO_UNLOAD_ON_FREE);
 640             /* See same code above in ossl_init_base() for an explanation. */
 641             OSSL_TRACE1(INIT,
 642                        "atexit: obtained DSO reference? %s\n",
 643                        (dso == NULL ? "No!" : "Yes."));
 644             DSO_free(dso);
 645             ERR_pop_to_mark();
 646         }
 647 # endif
 648     }
 649 #endif
 650
 651     if ((newhand = OPENSSL_malloc(sizeof(*newhand))) == NULL) {
 652         CRYPTOerr(CRYPTO_F_OPENSSL_ATEXIT, ERR_R_MALLOC_FAILURE);
 653         return 0;
 654     }
 655
 656     newhand->handler = handler;
 657     newhand->next = stop_handlers;
 658     stop_handlers = newhand;
 659
 660     return 1;
 661 }
 662
 663 #ifdef OPENSSL_SYS_UNIX
 664 /*
 665  * The following three functions are for OpenSSL developers.  This is
 666  * where we set/reset state across fork (called via pthread_atfork when
 667  * it exists, or manually by the application when it doesn't).
 668  *
 669  * WARNING!  If you put code in either OPENSSL_fork_parent or
 670  * OPENSSL_fork_child, you MUST MAKE SURE that they are async-signal-
 671  * safe.  See this link, for example:
 672  *      http://man7.org/linux/man-pages/man7/signal-safety.7.html
 673  */
 674
 675 void OPENSSL_fork_prepare(void)
 676 {
 677 }
 678
 679 void OPENSSL_fork_parent(void)
 680 {
 681 }
 682
 683 void OPENSSL_fork_child(void)
 684 {
 685     /* TODO(3.0): Inform all providers about a fork event */
 686 }
 687 #endif