eng_init.c revision 296465 
1/* crypto/engine/eng_init.c */
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 "eng_int.h"
57
58/*
59 * Initialise a engine type for use (or up its functional reference count if
60 * it's already in use). This version is only used internally.
61 */
62int engine_unlocked_init(ENGINE *e)
63{
64    int to_return = 1;
65
66    if ((e->funct_ref == 0) && e->init)
67        /*
68         * This is the first functional reference and the engine requires
69         * initialisation so we do it now.
70         */
71        to_return = e->init(e);
72    if (to_return) {
73        /*
74         * OK, we return a functional reference which is also a structural
75         * reference.
76         */
77        e->struct_ref++;
78        e->funct_ref++;
79        engine_ref_debug(e, 0, 1)
80            engine_ref_debug(e, 1, 1)
81    }
82    return to_return;
83}
84
85/*
86 * Free a functional reference to a engine type. This version is only used
87 * internally.
88 */
89int engine_unlocked_finish(ENGINE *e, int unlock_for_handlers)
90{
91    int to_return = 1;
92
93    /*
94     * Reduce the functional reference count here so if it's the terminating
95     * case, we can release the lock safely and call the finish() handler
96     * without risk of a race. We get a race if we leave the count until
97     * after and something else is calling "finish" at the same time -
98     * there's a chance that both threads will together take the count from 2
99     * to 0 without either calling finish().
100     */
101    e->funct_ref--;
102    engine_ref_debug(e, 1, -1);
103    if ((e->funct_ref == 0) && e->finish) {
104        if (unlock_for_handlers)
105            CRYPTO_w_unlock(CRYPTO_LOCK_ENGINE);
106        to_return = e->finish(e);
107        if (unlock_for_handlers)
108            CRYPTO_w_lock(CRYPTO_LOCK_ENGINE);
109        if (!to_return)
110            return 0;
111    }
112#ifdef REF_CHECK
113    if (e->funct_ref < 0) {
114        fprintf(stderr, "ENGINE_finish, bad functional reference count\n");
115        abort();
116    }
117#endif
118    /* Release the structural reference too */
119    if (!engine_free_util(e, 0)) {
120        ENGINEerr(ENGINE_F_ENGINE_UNLOCKED_FINISH, ENGINE_R_FINISH_FAILED);
121        return 0;
122    }
123    return to_return;
124}
125
126/* The API (locked) version of "init" */
127int ENGINE_init(ENGINE *e)
128{
129    int ret;
130    if (e == NULL) {
131        ENGINEerr(ENGINE_F_ENGINE_INIT, ERR_R_PASSED_NULL_PARAMETER);
132        return 0;
133    }
134    CRYPTO_w_lock(CRYPTO_LOCK_ENGINE);
135    ret = engine_unlocked_init(e);
136    CRYPTO_w_unlock(CRYPTO_LOCK_ENGINE);
137    return ret;
138}
139
140/* The API (locked) version of "finish" */
141int ENGINE_finish(ENGINE *e)
142{
143    int to_return = 1;
144
145    if (e == NULL) {
146        ENGINEerr(ENGINE_F_ENGINE_FINISH, ERR_R_PASSED_NULL_PARAMETER);
147        return 0;
148    }
149    CRYPTO_w_lock(CRYPTO_LOCK_ENGINE);
150    to_return = engine_unlocked_finish(e, 1);
151    CRYPTO_w_unlock(CRYPTO_LOCK_ENGINE);
152    if (!to_return) {
153        ENGINEerr(ENGINE_F_ENGINE_FINISH, ENGINE_R_FINISH_FAILED);
154        return 0;
155    }
156    return to_return;
157}
158