text: /*
   * Copyright 2016-2021 The OpenSSL Project Authors. All Rights Reserved.
   *
   * Licensed under the Apache License 2.0 (the "License").  You may not use
   * this file except in compliance with the License.  You can obtain a copy
   * in the file LICENSE in the source distribution or at
   * https://www.openssl.org/source/license.html
   */
  
  /* We need to use some engine deprecated APIs */
  #define OPENSSL_SUPPRESS_DEPRECATED
  
  #include "internal/e_os.h"
  #include "crypto/cryptlib.h"
  #include <openssl/err.h>
  #include "crypto/rand.h"
  #include "internal/bio.h"
  #include <openssl/evp.h>
  #include "crypto/evp.h"
  #include "internal/conf.h"
  #include "crypto/async.h"
  #include "crypto/engine.h"
  #include "internal/comp.h"
  #include "internal/err.h"
  #include "crypto/err.h"
  #include "crypto/objects.h"
  #include <stdlib.h>
  #include <assert.h>
  #include "internal/thread_once.h"
  #include "crypto/dso_conf.h"
  #include "internal/dso.h"
  #include "crypto/store.h"
  #include <openssl/cmp_util.h> /* for OSSL_CMP_log_close() */
  #include <openssl/trace.h>
  
  static int stopped = 0;
  static uint64_t optsdone = 0;
  
  typedef struct ossl_init_stop_st OPENSSL_INIT_STOP;
  struct ossl_init_stop_st {
      void (*handler)(void);
      OPENSSL_INIT_STOP *next;
  };
  
  static OPENSSL_INIT_STOP *stop_handlers = NULL;
  static CRYPTO_RWLOCK *init_lock = NULL;
  static CRYPTO_THREAD_LOCAL in_init_config_local;
  
  static CRYPTO_ONCE base = CRYPTO_ONCE_STATIC_INIT;
  static int base_inited = 0;
  DEFINE_RUN_ONCE_STATIC(ossl_init_base)
  {
      /* no need to init trace */
  
      OSSL_TRACE(INIT, "ossl_init_base: setting up stop handlers\n");
  #ifndef OPENSSL_NO_CRYPTO_MDEBUG
      ossl_malloc_setup_failures();
  #endif
  
      if ((init_lock = CRYPTO_THREAD_lock_new()) == NULL)
          goto err;
      OPENSSL_cpuid_setup();
  
      if (!ossl_init_thread())
          goto err;
  
      if (!CRYPTO_THREAD_init_local(&in_init_config_local, NULL))
          goto err;
  
      base_inited = 1;
      return 1;
  
  err:
      OSSL_TRACE(INIT, "ossl_init_base failed!\n");
      CRYPTO_THREAD_lock_free(init_lock);
      init_lock = NULL;
  
      return 0;
  }
  
  static CRYPTO_ONCE register_atexit = CRYPTO_ONCE_STATIC_INIT;
  #if !defined(OPENSSL_SYS_UEFI) && defined(_WIN32)
  static int win32atexit(void)
  {
      OPENSSL_cleanup();
      return 0;
  }
  #endif
  
  DEFINE_RUN_ONCE_STATIC(ossl_init_register_atexit)
  {
  #ifdef OPENSSL_INIT_DEBUG
      fprintf(stderr, "OPENSSL_INIT: ossl_init_register_atexit()\n");
  #endif
  #ifndef OPENSSL_SYS_UEFI
  # if defined(_WIN32) && !defined(__BORLANDC__)
      /* We use _onexit() in preference because it gets called on DLL unload */
      if (_onexit(win32atexit) == NULL)
          return 0;
  # else
      if (atexit(OPENSSL_cleanup) != 0)
          return 0;
  # endif
  #endif
  
      return 1;
  }
  
  DEFINE_RUN_ONCE_STATIC_ALT(ossl_init_no_register_atexit,
                             ossl_init_register_atexit)
  {
  #ifdef OPENSSL_INIT_DEBUG
      fprintf(stderr, "OPENSSL_INIT: ossl_init_no_register_atexit ok!\n");
  #endif
      /* Do nothing in this case */
      return 1;
  }
  
  static CRYPTO_ONCE load_crypto_nodelete = CRYPTO_ONCE_STATIC_INIT;
  DEFINE_RUN_ONCE_STATIC(ossl_init_load_crypto_nodelete)
  {
      OSSL_TRACE(INIT, "ossl_init_load_crypto_nodelete()\n");
  
  #if !defined(OPENSSL_USE_NODELETE) \
      && !defined(OPENSSL_NO_PINSHARED)
  # if defined(DSO_WIN32) && !defined(_WIN32_WCE)
      {
          HMODULE handle = NULL;
          BOOL ret;
  
          /* We don't use the DSO route for WIN32 because there is a better way */
          ret = GetModuleHandleEx(GET_MODULE_HANDLE_EX_FLAG_FROM_ADDRESS
                                  | GET_MODULE_HANDLE_EX_FLAG_PIN,
                                  (void *)&base_inited, &handle);
  
          OSSL_TRACE1(INIT,
                      "ossl_init_load_crypto_nodelete: "
                      "obtained DSO reference? %s\n",
                      (ret == TRUE ? "No!" : "Yes."));
          return (ret == TRUE) ? 1 : 0;
      }
  # elif !defined(DSO_NONE)
      /*
       * Deliberately leak a reference to ourselves. This will force the library
       * to remain loaded until the atexit() handler is run at process exit.
       */
      {
          DSO *dso;
          void *err;
  
          if (!err_shelve_state(&err))
              return 0;
  
          dso = DSO_dsobyaddr(&base_inited, DSO_FLAG_NO_UNLOAD_ON_FREE);
          /*
           * In case of No!, it is uncertain our exit()-handlers can still be
           * called. After dlclose() the whole library might have been unloaded
           * already.
           */
          OSSL_TRACE1(INIT, "obtained DSO reference? %s\n",
                      (dso == NULL ? "No!" : "Yes."));
          DSO_free(dso);
          err_unshelve_state(err);
      }
  # endif
  #endif
  
      return 1;
  }
  
  static CRYPTO_ONCE load_crypto_strings = CRYPTO_ONCE_STATIC_INIT;
  static int load_crypto_strings_inited = 0;
  DEFINE_RUN_ONCE_STATIC(ossl_init_load_crypto_strings)
  {
      int ret = 1;
      /*
       * OPENSSL_NO_AUTOERRINIT is provided here to prevent at compile time
       * pulling in all the error strings during static linking
       */
  #if !defined(OPENSSL_NO_ERR) && !defined(OPENSSL_NO_AUTOERRINIT)
      OSSL_TRACE(INIT, "ossl_err_load_crypto_strings()\n");
      ret = ossl_err_load_crypto_strings();
      load_crypto_strings_inited = 1;
  #endif
      return ret;
  }
  
  DEFINE_RUN_ONCE_STATIC_ALT(ossl_init_no_load_crypto_strings,
                             ossl_init_load_crypto_strings)
  {
      /* Do nothing in this case */
      return 1;
  }
  
  static CRYPTO_ONCE add_all_ciphers = CRYPTO_ONCE_STATIC_INIT;
  DEFINE_RUN_ONCE_STATIC(ossl_init_add_all_ciphers)
  {
      /*
       * OPENSSL_NO_AUTOALGINIT is provided here to prevent at compile time
       * pulling in all the ciphers during static linking
       */
  #ifndef OPENSSL_NO_AUTOALGINIT
      OSSL_TRACE(INIT, "openssl_add_all_ciphers_int()\n");
      openssl_add_all_ciphers_int();
  #endif
      return 1;
  }
  
  DEFINE_RUN_ONCE_STATIC_ALT(ossl_init_no_add_all_ciphers,
                             ossl_init_add_all_ciphers)
  {
      /* Do nothing */
      return 1;
  }
  
  static CRYPTO_ONCE add_all_digests = CRYPTO_ONCE_STATIC_INIT;
  DEFINE_RUN_ONCE_STATIC(ossl_init_add_all_digests)
  {
      /*
       * OPENSSL_NO_AUTOALGINIT is provided here to prevent at compile time
       * pulling in all the ciphers during static linking
       */
  #ifndef OPENSSL_NO_AUTOALGINIT
      OSSL_TRACE(INIT, "openssl_add_all_digests()\n");
      openssl_add_all_digests_int();
  #endif
      return 1;
  }
  
  DEFINE_RUN_ONCE_STATIC_ALT(ossl_init_no_add_all_digests,
                             ossl_init_add_all_digests)
  {
      /* Do nothing */
      return 1;
  }
  
  static CRYPTO_ONCE config = CRYPTO_ONCE_STATIC_INIT;
  static int config_inited = 0;
  static const OPENSSL_INIT_SETTINGS *conf_settings = NULL;
  DEFINE_RUN_ONCE_STATIC(ossl_init_config)
  {
      int ret = ossl_config_int(NULL);
  
      config_inited = 1;
      return ret;
  }
  DEFINE_RUN_ONCE_STATIC_ALT(ossl_init_config_settings, ossl_init_config)
  {
      int ret = ossl_config_int(conf_settings);
  
      config_inited = 1;
      return ret;
  }
  DEFINE_RUN_ONCE_STATIC_ALT(ossl_init_no_config, ossl_init_config)
  {
      OSSL_TRACE(INIT, "ossl_no_config_int()\n");
      ossl_no_config_int();
      config_inited = 1;
      return 1;
  }
  
  static CRYPTO_ONCE async = CRYPTO_ONCE_STATIC_INIT;
  static int async_inited = 0;
  DEFINE_RUN_ONCE_STATIC(ossl_init_async)
  {
      OSSL_TRACE(INIT, "async_init()\n");
      if (!async_init())
          return 0;
      async_inited = 1;
      return 1;
  }
  
  #ifndef OPENSSL_NO_ENGINE
  static CRYPTO_ONCE engine_openssl = CRYPTO_ONCE_STATIC_INIT;
  DEFINE_RUN_ONCE_STATIC(ossl_init_engine_openssl)
  {
      OSSL_TRACE(INIT, "engine_load_openssl_int()\n");
      engine_load_openssl_int();
      return 1;
  }
  # ifndef OPENSSL_NO_RDRAND
  static CRYPTO_ONCE engine_rdrand = CRYPTO_ONCE_STATIC_INIT;
  DEFINE_RUN_ONCE_STATIC(ossl_init_engine_rdrand)
  {
      OSSL_TRACE(INIT, "engine_load_rdrand_int()\n");
      engine_load_rdrand_int();
      return 1;
  }
  # endif
  static CRYPTO_ONCE engine_dynamic = CRYPTO_ONCE_STATIC_INIT;
  DEFINE_RUN_ONCE_STATIC(ossl_init_engine_dynamic)
  {
      OSSL_TRACE(INIT, "engine_load_dynamic_int()\n");
      engine_load_dynamic_int();
      return 1;
  }
  # ifndef OPENSSL_NO_STATIC_ENGINE
  #  ifndef OPENSSL_NO_DEVCRYPTOENG
  static CRYPTO_ONCE engine_devcrypto = CRYPTO_ONCE_STATIC_INIT;
  DEFINE_RUN_ONCE_STATIC(ossl_init_engine_devcrypto)
  {
      OSSL_TRACE(INIT, "engine_load_devcrypto_int()\n");
      engine_load_devcrypto_int();
      return 1;
  }
  #  endif
  #  if !defined(OPENSSL_NO_PADLOCKENG)
  static CRYPTO_ONCE engine_padlock = CRYPTO_ONCE_STATIC_INIT;
  DEFINE_RUN_ONCE_STATIC(ossl_init_engine_padlock)
  {
      OSSL_TRACE(INIT, "engine_load_padlock_int()\n");
      engine_load_padlock_int();
      return 1;
  }
  #  endif
  #  if defined(OPENSSL_SYS_WIN32) && !defined(OPENSSL_NO_CAPIENG)
  static CRYPTO_ONCE engine_capi = CRYPTO_ONCE_STATIC_INIT;
  DEFINE_RUN_ONCE_STATIC(ossl_init_engine_capi)
  {
      OSSL_TRACE(INIT, "engine_load_capi_int()\n");
      engine_load_capi_int();
      return 1;
  }
  #  endif
  #  if !defined(OPENSSL_NO_AFALGENG)
  static CRYPTO_ONCE engine_afalg = CRYPTO_ONCE_STATIC_INIT;
  DEFINE_RUN_ONCE_STATIC(ossl_init_engine_afalg)
  {
      OSSL_TRACE(INIT, "engine_load_afalg_int()\n");
      engine_load_afalg_int();
      return 1;
  }
  #  endif
  # endif
  #endif
  
  void OPENSSL_cleanup(void)
  {
      OPENSSL_INIT_STOP *currhandler, *lasthandler;
  
      /*
       * At some point we should consider looking at this function with a view to
       * moving most/all of this into onfree handlers in OSSL_LIB_CTX.
       */
  
      /* If we've not been inited then no need to deinit */
      if (!base_inited)
          return;
  
      /* Might be explicitly called and also by atexit */
      if (stopped)
          return;
      stopped = 1;
  
      /*
       * Thread stop may not get automatically called by the thread library for
       * the very last thread in some situations, so call it directly.
       */
      OPENSSL_thread_stop();
  
      currhandler = stop_handlers;
      while (currhandler != NULL) {
          currhandler->handler();
          lasthandler = currhandler;
          currhandler = currhandler->next;
          OPENSSL_free(lasthandler);
      }
      stop_handlers = NULL;
  
      CRYPTO_THREAD_lock_free(init_lock);
      init_lock = NULL;
  
      CRYPTO_THREAD_cleanup_local(&in_init_config_local);
  
      /*
       * We assume we are single-threaded for this function, i.e. no race
       * conditions for the various "*_inited" vars below.
       */
  
  #ifndef OPENSSL_NO_COMP
      OSSL_TRACE(INIT, "OPENSSL_cleanup: ossl_comp_zlib_cleanup()\n");
      ossl_comp_zlib_cleanup();
  #endif
  
      if (async_inited) {
          OSSL_TRACE(INIT, "OPENSSL_cleanup: async_deinit()\n");
          async_deinit();
      }
  
      if (load_crypto_strings_inited) {
          OSSL_TRACE(INIT, "OPENSSL_cleanup: err_free_strings_int()\n");
          err_free_strings_int();
      }
  
      /*
       * Note that cleanup order is important:
       * - ossl_rand_cleanup_int could call an ENGINE's RAND cleanup function so
       * must be called before engine_cleanup_int()
       * - ENGINEs use CRYPTO_EX_DATA and therefore, must be cleaned up
       * before the ex data handlers are wiped during default ossl_lib_ctx deinit.
       * - ossl_config_modules_free() can end up in ENGINE code so must be called
       * before engine_cleanup_int()
       * - ENGINEs and additional EVP algorithms might use added OIDs names so
       * ossl_obj_cleanup_int() must be called last
       */
      OSSL_TRACE(INIT, "OPENSSL_cleanup: ossl_rand_cleanup_int()\n");
      ossl_rand_cleanup_int();
  
      OSSL_TRACE(INIT, "OPENSSL_cleanup: ossl_config_modules_free()\n");
      ossl_config_modules_free();
  
  #ifndef OPENSSL_NO_ENGINE
      OSSL_TRACE(INIT, "OPENSSL_cleanup: engine_cleanup_int()\n");
      engine_cleanup_int();
  #endif
  
  #ifndef OPENSSL_NO_DEPRECATED_3_0
      OSSL_TRACE(INIT, "OPENSSL_cleanup: ossl_store_cleanup_int()\n");
      ossl_store_cleanup_int();
  #endif
  
      OSSL_TRACE(INIT, "OPENSSL_cleanup: ossl_lib_ctx_default_deinit()\n");
      ossl_lib_ctx_default_deinit();
  
      ossl_cleanup_thread();
  
      OSSL_TRACE(INIT, "OPENSSL_cleanup: bio_cleanup()\n");
      bio_cleanup();
  
      OSSL_TRACE(INIT, "OPENSSL_cleanup: evp_cleanup_int()\n");
      evp_cleanup_int();
  
      OSSL_TRACE(INIT, "OPENSSL_cleanup: ossl_obj_cleanup_int()\n");
      ossl_obj_cleanup_int();
  
      OSSL_TRACE(INIT, "OPENSSL_cleanup: err_int()\n");
      err_cleanup();
  
      OSSL_TRACE(INIT, "OPENSSL_cleanup: CRYPTO_secure_malloc_done()\n");
      CRYPTO_secure_malloc_done();
  
  #ifndef OPENSSL_NO_CMP
      OSSL_TRACE(INIT, "OPENSSL_cleanup: OSSL_CMP_log_close()\n");
      OSSL_CMP_log_close();
  #endif
  
      OSSL_TRACE(INIT, "OPENSSL_cleanup: ossl_trace_cleanup()\n");
      ossl_trace_cleanup();
  
      base_inited = 0;
  }
  
  /*
   * If this function is called with a non NULL settings value then it must be
   * called prior to any threads making calls to any OpenSSL functions,
   * i.e. passing a non-null settings value is assumed to be single-threaded.
   */
  int OPENSSL_init_crypto(uint64_t opts, const OPENSSL_INIT_SETTINGS *settings)
  {
      uint64_t tmp;
      int aloaddone = 0;
  
     /* Applications depend on 0 being returned when cleanup was already done */
      if (stopped) {
          if (!(opts & OPENSSL_INIT_BASE_ONLY))
              ERR_raise(ERR_LIB_CRYPTO, ERR_R_INIT_FAIL);
          return 0;
      }
  
      /*
       * We ignore failures from this function. It is probably because we are
       * on a platform that doesn't support lockless atomic loads (we may not
       * have created init_lock yet so we can't use it). This is just an
       * optimisation to skip the full checks in this function if we don't need
       * to, so we carry on regardless in the event of failure.
       *
       * There could be a race here with other threads, so that optsdone has not
       * been updated yet, even though the options have in fact been initialised.
       * This doesn't matter - it just means we will run the full function
       * unnecessarily - but all the critical code is contained in RUN_ONCE
       * functions anyway so we are safe.
       */
      if (CRYPTO_atomic_load(&optsdone, &tmp, NULL)) {
          if ((tmp & opts) == opts)
              return 1;
          aloaddone = 1;
      }
  
      /*
       * At some point we should look at this function with a view to moving
       * most/all of this into OSSL_LIB_CTX.
       *
       * When the caller specifies OPENSSL_INIT_BASE_ONLY, that should be the
       * *only* option specified.  With that option we return immediately after
       * doing the requested limited initialization.  Note that
       * err_shelve_state() called by us via ossl_init_load_crypto_nodelete()
       * re-enters OPENSSL_init_crypto() with OPENSSL_INIT_BASE_ONLY, but with
       * base already initialized this is a harmless NOOP.
       *
       * If we remain the only caller of err_shelve_state() the recursion should
       * perhaps be removed, but if in doubt, it can be left in place.
       */
      if (!RUN_ONCE(&base, ossl_init_base))
          return 0;
  
      if (opts & OPENSSL_INIT_BASE_ONLY)
          return 1;
  
      /*
       * init_lock should definitely be set up now, so we can now repeat the
       * same check from above but be sure that it will work even on platforms
       * without lockless CRYPTO_atomic_load
       */
      if (!aloaddone) {
          if (!CRYPTO_atomic_load(&optsdone, &tmp, init_lock))
              return 0;
          if ((tmp & opts) == opts)
              return 1;
      }
  
      /*
       * Now we don't always set up exit handlers, the INIT_BASE_ONLY calls
       * should not have the side-effect of setting up exit handlers, and
       * therefore, this code block is below the INIT_BASE_ONLY-conditioned early
       * return above.
       */
      if ((opts & OPENSSL_INIT_NO_ATEXIT) != 0) {
          if (!RUN_ONCE_ALT(&register_atexit, ossl_init_no_register_atexit,
                            ossl_init_register_atexit))
              return 0;
      } else if (!RUN_ONCE(&register_atexit, ossl_init_register_atexit)) {
          return 0;
      }
  
      if (!RUN_ONCE(&load_crypto_nodelete, ossl_init_load_crypto_nodelete))
          return 0;
  
      if ((opts & OPENSSL_INIT_NO_LOAD_CRYPTO_STRINGS)
              && !RUN_ONCE_ALT(&load_crypto_strings,
                               ossl_init_no_load_crypto_strings,
                               ossl_init_load_crypto_strings))
          return 0;
  
      if ((opts & OPENSSL_INIT_LOAD_CRYPTO_STRINGS)
              && !RUN_ONCE(&load_crypto_strings, ossl_init_load_crypto_strings))
          return 0;
  
      if ((opts & OPENSSL_INIT_NO_ADD_ALL_CIPHERS)
              && !RUN_ONCE_ALT(&add_all_ciphers, ossl_init_no_add_all_ciphers,
                               ossl_init_add_all_ciphers))
          return 0;
  
      if ((opts & OPENSSL_INIT_ADD_ALL_CIPHERS)
              && !RUN_ONCE(&add_all_ciphers, ossl_init_add_all_ciphers))
          return 0;
  
      if ((opts & OPENSSL_INIT_NO_ADD_ALL_DIGESTS)
              && !RUN_ONCE_ALT(&add_all_digests, ossl_init_no_add_all_digests,
                               ossl_init_add_all_digests))
          return 0;
  
      if ((opts & OPENSSL_INIT_ADD_ALL_DIGESTS)
              && !RUN_ONCE(&add_all_digests, ossl_init_add_all_digests))
          return 0;
  
      if ((opts & OPENSSL_INIT_ATFORK)
              && !openssl_init_fork_handlers())
          return 0;
  
      if ((opts & OPENSSL_INIT_NO_LOAD_CONFIG)
              && !RUN_ONCE_ALT(&config, ossl_init_no_config, ossl_init_config))
          return 0;
  
      if (opts & OPENSSL_INIT_LOAD_CONFIG) {
          int loading = CRYPTO_THREAD_get_local(&in_init_config_local) != NULL;
  
          /* If called recursively from OBJ_ calls, just skip it. */
          if (!loading) {
              int ret;
  
              if (!CRYPTO_THREAD_set_local(&in_init_config_local, (void *)-1))
                  return 0;
              if (settings == NULL) {
                  ret = RUN_ONCE(&config, ossl_init_config);
              } else {
                  if (!CRYPTO_THREAD_write_lock(init_lock))
                      return 0;
                  conf_settings = settings;
                  ret = RUN_ONCE_ALT(&config, ossl_init_config_settings,
                                     ossl_init_config);
                  conf_settings = NULL;
                  CRYPTO_THREAD_unlock(init_lock);
              }
  
              if (ret <= 0)
                  return 0;
          }
      }
  
      if ((opts & OPENSSL_INIT_ASYNC)
              && !RUN_ONCE(&async, ossl_init_async))
          return 0;
  
  #ifndef OPENSSL_NO_ENGINE
      if ((opts & OPENSSL_INIT_ENGINE_OPENSSL)
              && !RUN_ONCE(&engine_openssl, ossl_init_engine_openssl))
          return 0;
  # ifndef OPENSSL_NO_RDRAND
      if ((opts & OPENSSL_INIT_ENGINE_RDRAND)
              && !RUN_ONCE(&engine_rdrand, ossl_init_engine_rdrand))
          return 0;
  # endif
      if ((opts & OPENSSL_INIT_ENGINE_DYNAMIC)
              && !RUN_ONCE(&engine_dynamic, ossl_init_engine_dynamic))
          return 0;
  # ifndef OPENSSL_NO_STATIC_ENGINE
  #  ifndef OPENSSL_NO_DEVCRYPTOENG
      if ((opts & OPENSSL_INIT_ENGINE_CRYPTODEV)
              && !RUN_ONCE(&engine_devcrypto, ossl_init_engine_devcrypto))
          return 0;
  #  endif
  #  if !defined(OPENSSL_NO_PADLOCKENG)
      if ((opts & OPENSSL_INIT_ENGINE_PADLOCK)
              && !RUN_ONCE(&engine_padlock, ossl_init_engine_padlock))
          return 0;
  #  endif
  #  if defined(OPENSSL_SYS_WIN32) && !defined(OPENSSL_NO_CAPIENG)
      if ((opts & OPENSSL_INIT_ENGINE_CAPI)
              && !RUN_ONCE(&engine_capi, ossl_init_engine_capi))
          return 0;
  #  endif
  #  if !defined(OPENSSL_NO_AFALGENG)
      if ((opts & OPENSSL_INIT_ENGINE_AFALG)
              && !RUN_ONCE(&engine_afalg, ossl_init_engine_afalg))
          return 0;
  #  endif
  # endif
      if (opts & (OPENSSL_INIT_ENGINE_ALL_BUILTIN
                  | OPENSSL_INIT_ENGINE_OPENSSL
                  | OPENSSL_INIT_ENGINE_AFALG)) {
          ENGINE_register_all_complete();
      }
  #endif
  
      if (!CRYPTO_atomic_or(&optsdone, opts, &tmp, init_lock))
          return 0;
  
      return 1;
  }
  
  int OPENSSL_atexit(void (*handler)(void))
  {
      OPENSSL_INIT_STOP *newhand;
  
  #if !defined(OPENSSL_USE_NODELETE)\
      && !defined(OPENSSL_NO_PINSHARED)
      {
          union {
              void *sym;
              void (*func)(void);
          } handlersym;
  
          handlersym.func = handler;
  # if defined(DSO_WIN32) && !defined(_WIN32_WCE)
          {
              HMODULE handle = NULL;
              BOOL ret;
  
              /*
               * We don't use the DSO route for WIN32 because there is a better
               * way
               */
              ret = GetModuleHandleEx(GET_MODULE_HANDLE_EX_FLAG_FROM_ADDRESS
                                      | GET_MODULE_HANDLE_EX_FLAG_PIN,
                                      handlersym.sym, &handle);
  
              if (!ret)
                  return 0;
          }
  # elif !defined(DSO_NONE)
          /*
           * Deliberately leak a reference to the handler. This will force the
           * library/code containing the handler to remain loaded until we run the
           * atexit handler. If -znodelete has been used then this is
           * unnecessary.
           */
          {
              DSO *dso = NULL;
  
              ERR_set_mark();
              dso = DSO_dsobyaddr(handlersym.sym, DSO_FLAG_NO_UNLOAD_ON_FREE);
              /* See same code above in ossl_init_base() for an explanation. */
              OSSL_TRACE1(INIT,
                         "atexit: obtained DSO reference? %s\n",
                         (dso == NULL ? "No!" : "Yes."));
              DSO_free(dso);
              ERR_pop_to_mark();
          }
  # endif
      }
  #endif
  
      if ((newhand = OPENSSL_malloc(sizeof(*newhand))) == NULL) {
          ERR_raise(ERR_LIB_CRYPTO, ERR_R_MALLOC_FAILURE);
          return 0;
      }
  
      newhand->handler = handler;
      newhand->next = stop_handlers;
      stop_handlers = newhand;
  
      return 1;
  }
  
  