lib/libcrypto/engine/eng_init.c

   1 /* $OpenBSD: eng_init.c,v 1.8 2017/01/29 17:49:23 beck Exp $ */
   2 /* ====================================================================
   3  * Copyright (c) 1999-2001 The OpenSSL Project.  All rights reserved.
   4  *
   5  * Redistribution and use in source and binary forms, with or without
   6  * modification, are permitted provided that the following conditions
   7  * are met:
   8  *
   9  * 1. Redistributions of source code must retain the above copyright
  10  *    notice, this list of conditions and the following disclaimer.
  11  *
  12  * 2. Redistributions in binary form must reproduce the above copyright
  13  *    notice, this list of conditions and the following disclaimer in
  14  *    the documentation and/or other materials provided with the
  15  *    distribution.
  16  *
  17  * 3. All advertising materials mentioning features or use of this
  18  *    software must display the following acknowledgment:
  19  *    "This product includes software developed by the OpenSSL Project
  20  *    for use in the OpenSSL Toolkit. (http://www.OpenSSL.org/)"
  21  *
  22  * 4. The names "OpenSSL Toolkit" and "OpenSSL Project" must not be used to
  23  *    endorse or promote products derived from this software without
  24  *    prior written permission. For written permission, please contact
  25  *    licensing@OpenSSL.org.
  26  *
  27  * 5. Products derived from this software may not be called "OpenSSL"
  28  *    nor may "OpenSSL" appear in their names without prior written
  29  *    permission of the OpenSSL Project.
  30  *
  31  * 6. Redistributions of any form whatsoever must retain the following
  32  *    acknowledgment:
  33  *    "This product includes software developed by the OpenSSL Project
  34  *    for use in the OpenSSL Toolkit (http://www.OpenSSL.org/)"
  35  *
  36  * THIS SOFTWARE IS PROVIDED BY THE OpenSSL PROJECT ``AS IS'' AND ANY
  37  * EXPRESSED OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
  38  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR
  39  * PURPOSE ARE DISCLAIMED.  IN NO EVENT SHALL THE OpenSSL PROJECT OR
  40  * ITS CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
  41  * SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT
  42  * NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES;
  43  * LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
  44  * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT,
  45  * STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE)
  46  * ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED
  47  * OF THE POSSIBILITY OF SUCH DAMAGE.
  48  * ====================================================================
  49  *
  50  * This product includes cryptographic software written by Eric Young
  51  * (eay@cryptsoft.com).  This product includes software written by Tim
  52  * Hudson (tjh@cryptsoft.com).
  53  *
  54  */
  55
  56 #include <openssl/err.h>
  57
  58 #include "eng_int.h"
  59
  60 /* Initialise a engine type for use (or up its functional reference count
  61  * if it's already in use). This version is only used internally. */
  62 int
  63 engine_unlocked_init(ENGINE *e)
  64 {
  65         int to_return = 1;
  66
  67         if ((e->funct_ref == 0) && e->init)
  68                 /* This is the first functional reference and the engine
  69                  * requires initialisation so we do it now. */
  70                 to_return = e->init(e);
  71         if (to_return) {
  72                 /* OK, we return a functional reference which is also a
  73                  * structural reference. */
  74                 e->struct_ref++;
  75                 e->funct_ref++;
  76                 engine_ref_debug(e, 0, 1)
  77                 engine_ref_debug(e, 1, 1)
  78         }
  79         return to_return;
  80 }
  81
  82 /* Free a functional reference to a engine type. This version is only used
  83  * internally. */
  84 int
  85 engine_unlocked_finish(ENGINE *e, int unlock_for_handlers)
  86 {
  87         int to_return = 1;
  88
  89         /* Reduce the functional reference count here so if it's the terminating
  90          * case, we can release the lock safely and call the finish() handler
  91          * without risk of a race. We get a race if we leave the count until
  92          * after and something else is calling "finish" at the same time -
  93          * there's a chance that both threads will together take the count from
  94          * 2 to 0 without either calling finish(). */
  95         e->funct_ref--;
  96         engine_ref_debug(e, 1, -1);
  97         if ((e->funct_ref == 0) && e->finish) {
  98                 if (unlock_for_handlers)
  99                         CRYPTO_w_unlock(CRYPTO_LOCK_ENGINE);
 100                 to_return = e->finish(e);
 101                 if (unlock_for_handlers)
 102                         CRYPTO_w_lock(CRYPTO_LOCK_ENGINE);
 103                 if (!to_return)
 104                         return 0;
 105         }
 106
 107         /* Release the structural reference too */
 108         if (!engine_free_util(e, 0)) {
 109                 ENGINEerror(ENGINE_R_FINISH_FAILED);
 110                 return 0;
 111         }
 112         return to_return;
 113 }
 114
 115 /* The API (locked) version of "init" */
 116 int
 117 ENGINE_init(ENGINE *e)
 118 {
 119         int ret;
 120
 121         if (e == NULL) {
 122                 ENGINEerror(ERR_R_PASSED_NULL_PARAMETER);
 123                 return 0;
 124         }
 125         CRYPTO_w_lock(CRYPTO_LOCK_ENGINE);
 126         ret = engine_unlocked_init(e);
 127         CRYPTO_w_unlock(CRYPTO_LOCK_ENGINE);
 128         return ret;
 129 }
 130
 131 /* The API (locked) version of "finish" */
 132 int
 133 ENGINE_finish(ENGINE *e)
 134 {
 135         int to_return = 1;
 136
 137         if (e == NULL) {
 138                 ENGINEerror(ERR_R_PASSED_NULL_PARAMETER);
 139                 return 0;
 140         }
 141         CRYPTO_w_lock(CRYPTO_LOCK_ENGINE);
 142         to_return = engine_unlocked_finish(e, 1);
 143         CRYPTO_w_unlock(CRYPTO_LOCK_ENGINE);
 144         if (!to_return) {
 145                 ENGINEerror(ENGINE_R_FINISH_FAILED);
 146                 return 0;
 147         }
 148         return to_return;
 149 }