[thirdparty/openssl.git] / crypto / engine / eng_list.c

/* crypto/engine/eng_list.c */
/*
 * Written by Geoff Thorpe (geoff@geoffthorpe.net) for the OpenSSL project
 * 2000.
 */
/* ====================================================================
 * Copyright (c) 1999-2001 The OpenSSL Project.  All rights reserved.
 *
 * Redistribution and use in source and binary forms, with or without
 * modification, are permitted provided that the following conditions
 * are met:
 *
 * 1. Redistributions of source code must retain the above copyright
 *    notice, this list of conditions and the following disclaimer.
 *
 * 2. Redistributions in binary form must reproduce the above copyright
 *    notice, this list of conditions and the following disclaimer in
 *    the documentation and/or other materials provided with the
 *    distribution.
 *
 * 3. All advertising materials mentioning features or use of this
 *    software must display the following acknowledgment:
 *    "This product includes software developed by the OpenSSL Project
 *    for use in the OpenSSL Toolkit. (http://www.OpenSSL.org/)"
 *
 * 4. The names "OpenSSL Toolkit" and "OpenSSL Project" must not be used to
 *    endorse or promote products derived from this software without
 *    prior written permission. For written permission, please contact
 *    licensing@OpenSSL.org.
 *
 * 5. Products derived from this software may not be called "OpenSSL"
 *    nor may "OpenSSL" appear in their names without prior written
 *    permission of the OpenSSL Project.
 *
 * 6. Redistributions of any form whatsoever must retain the following
 *    acknowledgment:
 *    "This product includes software developed by the OpenSSL Project
 *    for use in the OpenSSL Toolkit (http://www.OpenSSL.org/)"
 *
 * THIS SOFTWARE IS PROVIDED BY THE OpenSSL PROJECT ``AS IS'' AND ANY
 * EXPRESSED OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR
 * PURPOSE ARE DISCLAIMED.  IN NO EVENT SHALL THE OpenSSL PROJECT OR
 * ITS CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
 * SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT
 * NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES;
 * LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT,
 * STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE)
 * ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED
 * OF THE POSSIBILITY OF SUCH DAMAGE.
 * ====================================================================
 *
 * This product includes cryptographic software written by Eric Young
 * (eay@cryptsoft.com).  This product includes software written by Tim
 * Hudson (tjh@cryptsoft.com).
 *
 */
/* ====================================================================
 * Copyright 2002 Sun Microsystems, Inc. ALL RIGHTS RESERVED.
 * ECDH support in OpenSSL originally developed by
 * SUN MICROSYSTEMS, INC., and contributed to the OpenSSL project.
 */

#include "eng_int.h"

/*
 * The linked-list of pointers to engine types. engine_list_head incorporates
 * an implicit structural reference but engine_list_tail does not - the
 * latter is a computational niceity and only points to something that is
 * already pointed to by its predecessor in the list (or engine_list_head
 * itself). In the same way, the use of the "prev" pointer in each ENGINE is
 * to save excessive list iteration, it doesn't correspond to an extra
 * structural reference. Hence, engine_list_head, and each non-null "next"
 * pointer account for the list itself assuming exactly 1 structural
 * reference on each list member.
 */
static ENGINE *engine_list_head = NULL;
static ENGINE *engine_list_tail = NULL;

/*
 * This cleanup function is only needed internally. If it should be called,
 * we register it with the "ENGINE_cleanup()" stack to be called during
 * cleanup.
 */

static void engine_list_cleanup(void)
{
    ENGINE *iterator = engine_list_head;

    while (iterator != NULL) {
        ENGINE_remove(iterator);
        iterator = engine_list_head;
    }
    return;
}

/*
 * These static functions starting with a lower case "engine_" always take
 * place when CRYPTO_LOCK_ENGINE has been locked up.
 */
static int engine_list_add(ENGINE *e)
{
    int conflict = 0;
    ENGINE *iterator = NULL;

    if (e == NULL) {
        ENGINEerr(ENGINE_F_ENGINE_LIST_ADD, ERR_R_PASSED_NULL_PARAMETER);
        return 0;
    }
    iterator = engine_list_head;
    while (iterator && !conflict) {
        conflict = (strcmp(iterator->id, e->id) == 0);
        iterator = iterator->next;
    }
    if (conflict) {
        ENGINEerr(ENGINE_F_ENGINE_LIST_ADD, ENGINE_R_CONFLICTING_ENGINE_ID);
        return 0;
    }
    if (engine_list_head == NULL) {
        /* We are adding to an empty list. */
        if (engine_list_tail) {
            ENGINEerr(ENGINE_F_ENGINE_LIST_ADD, ENGINE_R_INTERNAL_LIST_ERROR);
            return 0;
        }
        engine_list_head = e;
        e->prev = NULL;
        /*
         * The first time the list allocates, we should register the cleanup.
         */
        engine_cleanup_add_last(engine_list_cleanup);
    } else {
        /* We are adding to the tail of an existing list. */
        if ((engine_list_tail == NULL) || (engine_list_tail->next != NULL)) {
            ENGINEerr(ENGINE_F_ENGINE_LIST_ADD, ENGINE_R_INTERNAL_LIST_ERROR);
            return 0;
        }
        engine_list_tail->next = e;
        e->prev = engine_list_tail;
    }
    /*
     * Having the engine in the list assumes a structural reference.
     */
    e->struct_ref++;
    engine_ref_debug(e, 0, 1)
        /* However it came to be, e is the last item in the list. */
        engine_list_tail = e;
    e->next = NULL;
    return 1;
}

static int engine_list_remove(ENGINE *e)
{
    ENGINE *iterator;

    if (e == NULL) {
        ENGINEerr(ENGINE_F_ENGINE_LIST_REMOVE, ERR_R_PASSED_NULL_PARAMETER);
        return 0;
    }
    /* We need to check that e is in our linked list! */
    iterator = engine_list_head;
    while (iterator && (iterator != e))
        iterator = iterator->next;
    if (iterator == NULL) {
        ENGINEerr(ENGINE_F_ENGINE_LIST_REMOVE,
                  ENGINE_R_ENGINE_IS_NOT_IN_LIST);
        return 0;
    }
    /* un-link e from the chain. */
    if (e->next)
        e->next->prev = e->prev;
    if (e->prev)
        e->prev->next = e->next;
    /* Correct our head/tail if necessary. */
    if (engine_list_head == e)
        engine_list_head = e->next;
    if (engine_list_tail == e)
        engine_list_tail = e->prev;
    engine_free_util(e, 0);
    return 1;
}

/* Get the first/last "ENGINE" type available. */
ENGINE *ENGINE_get_first(void)
{
    ENGINE *ret;

    CRYPTO_w_lock(CRYPTO_LOCK_ENGINE);
    ret = engine_list_head;
    if (ret) {
        ret->struct_ref++;
        engine_ref_debug(ret, 0, 1)
    }
    CRYPTO_w_unlock(CRYPTO_LOCK_ENGINE);
    return ret;
}

ENGINE *ENGINE_get_last(void)
{
    ENGINE *ret;

    CRYPTO_w_lock(CRYPTO_LOCK_ENGINE);
    ret = engine_list_tail;
    if (ret) {
        ret->struct_ref++;
        engine_ref_debug(ret, 0, 1)
    }
    CRYPTO_w_unlock(CRYPTO_LOCK_ENGINE);
    return ret;
}

/* Iterate to the next/previous "ENGINE" type (NULL = end of the list). */
ENGINE *ENGINE_get_next(ENGINE *e)
{
    ENGINE *ret = NULL;
    if (e == NULL) {
        ENGINEerr(ENGINE_F_ENGINE_GET_NEXT, ERR_R_PASSED_NULL_PARAMETER);
        return 0;
    }
    CRYPTO_w_lock(CRYPTO_LOCK_ENGINE);
    ret = e->next;
    if (ret) {
        /* Return a valid structural refernce to the next ENGINE */
        ret->struct_ref++;
        engine_ref_debug(ret, 0, 1)
    }
    CRYPTO_w_unlock(CRYPTO_LOCK_ENGINE);
    /* Release the structural reference to the previous ENGINE */
    ENGINE_free(e);
    return ret;
}

ENGINE *ENGINE_get_prev(ENGINE *e)
{
    ENGINE *ret = NULL;
    if (e == NULL) {
        ENGINEerr(ENGINE_F_ENGINE_GET_PREV, ERR_R_PASSED_NULL_PARAMETER);
        return 0;
    }
    CRYPTO_w_lock(CRYPTO_LOCK_ENGINE);
    ret = e->prev;
    if (ret) {
        /* Return a valid structural reference to the next ENGINE */
        ret->struct_ref++;
        engine_ref_debug(ret, 0, 1)
    }
    CRYPTO_w_unlock(CRYPTO_LOCK_ENGINE);
    /* Release the structural reference to the previous ENGINE */
    ENGINE_free(e);
    return ret;
}

/* Add another "ENGINE" type into the list. */
int ENGINE_add(ENGINE *e)
{
    int to_return = 1;
    if (e == NULL) {
        ENGINEerr(ENGINE_F_ENGINE_ADD, ERR_R_PASSED_NULL_PARAMETER);
        return 0;
    }
    if ((e->id == NULL) || (e->name == NULL)) {
        ENGINEerr(ENGINE_F_ENGINE_ADD, ENGINE_R_ID_OR_NAME_MISSING);
        return 0;
    }
    CRYPTO_w_lock(CRYPTO_LOCK_ENGINE);
    if (!engine_list_add(e)) {
        ENGINEerr(ENGINE_F_ENGINE_ADD, ENGINE_R_INTERNAL_LIST_ERROR);
        to_return = 0;
    }
    CRYPTO_w_unlock(CRYPTO_LOCK_ENGINE);
    return to_return;
}

/* Remove an existing "ENGINE" type from the array. */
int ENGINE_remove(ENGINE *e)
{
    int to_return = 1;
    if (e == NULL) {
        ENGINEerr(ENGINE_F_ENGINE_REMOVE, ERR_R_PASSED_NULL_PARAMETER);
        return 0;
    }
    CRYPTO_w_lock(CRYPTO_LOCK_ENGINE);
    if (!engine_list_remove(e)) {
        ENGINEerr(ENGINE_F_ENGINE_REMOVE, ENGINE_R_INTERNAL_LIST_ERROR);
        to_return = 0;
    }
    CRYPTO_w_unlock(CRYPTO_LOCK_ENGINE);
    return to_return;
}

static void engine_cpy(ENGINE *dest, const ENGINE *src)
{
    dest->id = src->id;
    dest->name = src->name;
#ifndef OPENSSL_NO_RSA
    dest->rsa_meth = src->rsa_meth;
#endif
#ifndef OPENSSL_NO_DSA
    dest->dsa_meth = src->dsa_meth;
#endif
#ifndef OPENSSL_NO_DH
    dest->dh_meth = src->dh_meth;
#endif
#ifndef OPENSSL_NO_EC
    dest->ecdh_meth = src->ecdh_meth;
    dest->ecdsa_meth = src->ecdsa_meth;
#endif
    dest->rand_meth = src->rand_meth;
    dest->store_meth = src->store_meth;
    dest->ciphers = src->ciphers;
    dest->digests = src->digests;
    dest->pkey_meths = src->pkey_meths;
    dest->destroy = src->destroy;
    dest->init = src->init;
    dest->finish = src->finish;
    dest->ctrl = src->ctrl;
    dest->load_privkey = src->load_privkey;
    dest->load_pubkey = src->load_pubkey;
    dest->cmd_defns = src->cmd_defns;
    dest->flags = src->flags;
}

ENGINE *ENGINE_by_id(const char *id)
{
    ENGINE *iterator;
    char *load_dir = NULL;
    if (id == NULL) {
        ENGINEerr(ENGINE_F_ENGINE_BY_ID, ERR_R_PASSED_NULL_PARAMETER);
        return NULL;
    }
    CRYPTO_w_lock(CRYPTO_LOCK_ENGINE);
    iterator = engine_list_head;
    while (iterator && (strcmp(id, iterator->id) != 0))
        iterator = iterator->next;
    if (iterator != NULL) {
        /*
         * We need to return a structural reference. If this is an ENGINE
         * type that returns copies, make a duplicate - otherwise increment
         * the existing ENGINE's reference count.
         */
        if (iterator->flags & ENGINE_FLAGS_BY_ID_COPY) {
            ENGINE *cp = ENGINE_new();
            if (cp == NULL)
                iterator = NULL;
            else {
                engine_cpy(cp, iterator);
                iterator = cp;
            }
        } else {
            iterator->struct_ref++;
            engine_ref_debug(iterator, 0, 1)
        }
    }
    CRYPTO_w_unlock(CRYPTO_LOCK_ENGINE);
    if (iterator != NULL)
        return iterator;
    /*
     * Prevent infinite recusrion if we're looking for the dynamic engine.
     */
    if (strcmp(id, "dynamic")) {
# ifdef OPENSSL_SYS_VMS
        if ((load_dir = getenv("OPENSSL_ENGINES")) == 0)
            load_dir = "SSLROOT:[ENGINES]";
# else
        if ((load_dir = getenv("OPENSSL_ENGINES")) == 0)
            load_dir = ENGINESDIR;
# endif
        iterator = ENGINE_by_id("dynamic");
        if (!iterator || !ENGINE_ctrl_cmd_string(iterator, "ID", id, 0) ||
            !ENGINE_ctrl_cmd_string(iterator, "DIR_LOAD", "2", 0) ||
            !ENGINE_ctrl_cmd_string(iterator, "DIR_ADD",
                                    load_dir, 0) ||
            !ENGINE_ctrl_cmd_string(iterator, "LIST_ADD", "1", 0) ||
            !ENGINE_ctrl_cmd_string(iterator, "LOAD", NULL, 0))
            goto notfound;
        return iterator;
    }
 notfound:
    ENGINE_free(iterator);
    ENGINEerr(ENGINE_F_ENGINE_BY_ID, ENGINE_R_NO_SUCH_ENGINE);
    ERR_add_error_data(2, "id=", id);
    return NULL;
    /* EEK! Experimental code ends */
}

int ENGINE_up_ref(ENGINE *e)
{
    if (e == NULL) {
        ENGINEerr(ENGINE_F_ENGINE_UP_REF, ERR_R_PASSED_NULL_PARAMETER);
        return 0;
    }
    CRYPTO_add(&e->struct_ref, 1, CRYPTO_LOCK_ENGINE);
    return 1;
}
Commit	Line	Data
2b671586	1	/* crypto/engine/eng_list.c */
0f113f3e MC	2	/*
	3	* Written by Geoff Thorpe (geoff@geoffthorpe.net) for the OpenSSL project
	4	* 2000.
5270e702 RL	5	*/
5270e702 RL	6	/* ====================================================================
2b671586	7	* Copyright (c) 1999-2001 The OpenSSL Project. All rights reserved.
5270e702 RL	8	*
	9	* Redistribution and use in source and binary forms, with or without
	10	* modification, are permitted provided that the following conditions
	11	* are met:
	12	*
	13	* 1. Redistributions of source code must retain the above copyright
0f113f3e	14	* notice, this list of conditions and the following disclaimer.
5270e702 RL	15	*
	16	* 2. Redistributions in binary form must reproduce the above copyright
	17	* notice, this list of conditions and the following disclaimer in
	18	* the documentation and/or other materials provided with the
	19	* distribution.
	20	*
	21	* 3. All advertising materials mentioning features or use of this
	22	* software must display the following acknowledgment:
	23	* "This product includes software developed by the OpenSSL Project
	24	* for use in the OpenSSL Toolkit. (http://www.OpenSSL.org/)"
	25	*
	26	* 4. The names "OpenSSL Toolkit" and "OpenSSL Project" must not be used to
	27	* endorse or promote products derived from this software without
	28	* prior written permission. For written permission, please contact
	29	* licensing@OpenSSL.org.
	30	*
	31	* 5. Products derived from this software may not be called "OpenSSL"
	32	* nor may "OpenSSL" appear in their names without prior written
	33	* permission of the OpenSSL Project.
	34	*
	35	* 6. Redistributions of any form whatsoever must retain the following
	36	* acknowledgment:
	37	* "This product includes software developed by the OpenSSL Project
	38	* for use in the OpenSSL Toolkit (http://www.OpenSSL.org/)"
	39	*
	40	* THIS SOFTWARE IS PROVIDED BY THE OpenSSL PROJECT ``AS IS'' AND ANY
	41	* EXPRESSED OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
	42	* IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR
	43	* PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE OpenSSL PROJECT OR
	44	* ITS CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
	45	* SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT
	46	* NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES;
	47	* LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
	48	* HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT,
	49	* STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE)
	50	* ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED
	51	* OF THE POSSIBILITY OF SUCH DAMAGE.
	52	* ====================================================================
	53	*
	54	* This product includes cryptographic software written by Eric Young
	55	* (eay@cryptsoft.com). This product includes software written by Tim
	56	* Hudson (tjh@cryptsoft.com).
	57	*
	58	*/
e172d60d BM	59	/* ====================================================================
e172d60d BM	60	* Copyright 2002 Sun Microsystems, Inc. ALL RIGHTS RESERVED.
0f113f3e	61	* ECDH support in OpenSSL originally developed by
e172d60d BM	62	* SUN MICROSYSTEMS, INC., and contributed to the OpenSSL project.
e172d60d BM	63	*/
5270e702	64
14cfde9c	65	#include "eng_int.h"
5270e702	66
0f113f3e MC	67	/*
	68	* The linked-list of pointers to engine types. engine_list_head incorporates
	69	* an implicit structural reference but engine_list_tail does not - the
	70	* latter is a computational niceity and only points to something that is
	71	* already pointed to by its predecessor in the list (or engine_list_head
	72	* itself). In the same way, the use of the "prev" pointer in each ENGINE is
	73	* to save excessive list iteration, it doesn't correspond to an extra
	74	* structural reference. Hence, engine_list_head, and each non-null "next"
	75	* pointer account for the list itself assuming exactly 1 structural
	76	* reference on each list member.
	77	*/
5270e702 RL	78	static ENGINE *engine_list_head = NULL;
5270e702 RL	79	static ENGINE *engine_list_tail = NULL;
b6d1e52d	80
0f113f3e MC	81	/*
	82	* This cleanup function is only needed internally. If it should be called,
	83	* we register it with the "ENGINE_cleanup()" stack to be called during
	84	* cleanup.
	85	*/
b6d1e52d GT	86
b6d1e52d GT	87	static void engine_list_cleanup(void)
0f113f3e MC	88	{
0f113f3e MC	89	ENGINE *iterator = engine_list_head;
b6d1e52d	90
0f113f3e MC	91	while (iterator != NULL) {
	92	ENGINE_remove(iterator);
	93	iterator = engine_list_head;
	94	}
	95	return;
	96	}
5270e702	97
0f113f3e MC	98	/*
	99	* These static functions starting with a lower case "engine_" always take
	100	* place when CRYPTO_LOCK_ENGINE has been locked up.
	101	*/
5270e702	102	static int engine_list_add(ENGINE *e)
0f113f3e MC	103	{
	104	int conflict = 0;
	105	ENGINE *iterator = NULL;
5270e702	106
0f113f3e MC	107	if (e == NULL) {
	108	ENGINEerr(ENGINE_F_ENGINE_LIST_ADD, ERR_R_PASSED_NULL_PARAMETER);
	109	return 0;
	110	}
	111	iterator = engine_list_head;
	112	while (iterator && !conflict) {
	113	conflict = (strcmp(iterator->id, e->id) == 0);
	114	iterator = iterator->next;
	115	}
	116	if (conflict) {
	117	ENGINEerr(ENGINE_F_ENGINE_LIST_ADD, ENGINE_R_CONFLICTING_ENGINE_ID);
	118	return 0;
	119	}
	120	if (engine_list_head == NULL) {
	121	/* We are adding to an empty list. */
	122	if (engine_list_tail) {
	123	ENGINEerr(ENGINE_F_ENGINE_LIST_ADD, ENGINE_R_INTERNAL_LIST_ERROR);
	124	return 0;
	125	}
	126	engine_list_head = e;
	127	e->prev = NULL;
	128	/*
	129	* The first time the list allocates, we should register the cleanup.
	130	*/
	131	engine_cleanup_add_last(engine_list_cleanup);
	132	} else {
	133	/* We are adding to the tail of an existing list. */
	134	if ((engine_list_tail == NULL) \|\| (engine_list_tail->next != NULL)) {
	135	ENGINEerr(ENGINE_F_ENGINE_LIST_ADD, ENGINE_R_INTERNAL_LIST_ERROR);
	136	return 0;
	137	}
	138	engine_list_tail->next = e;
	139	e->prev = engine_list_tail;
	140	}
	141	/*
	142	* Having the engine in the list assumes a structural reference.
	143	*/
	144	e->struct_ref++;
	145	engine_ref_debug(e, 0, 1)
	146	/* However it came to be, e is the last item in the list. */
	147	engine_list_tail = e;
	148	e->next = NULL;
	149	return 1;
	150	}
5270e702 RL	151
5270e702 RL	152	static int engine_list_remove(ENGINE *e)
0f113f3e MC	153	{
0f113f3e MC	154	ENGINE *iterator;
5270e702	155
0f113f3e MC	156	if (e == NULL) {
	157	ENGINEerr(ENGINE_F_ENGINE_LIST_REMOVE, ERR_R_PASSED_NULL_PARAMETER);
	158	return 0;
	159	}
	160	/* We need to check that e is in our linked list! */
	161	iterator = engine_list_head;
	162	while (iterator && (iterator != e))
	163	iterator = iterator->next;
	164	if (iterator == NULL) {
	165	ENGINEerr(ENGINE_F_ENGINE_LIST_REMOVE,
	166	ENGINE_R_ENGINE_IS_NOT_IN_LIST);
	167	return 0;
	168	}
	169	/* un-link e from the chain. */
	170	if (e->next)
	171	e->next->prev = e->prev;
	172	if (e->prev)
	173	e->prev->next = e->next;
	174	/* Correct our head/tail if necessary. */
	175	if (engine_list_head == e)
	176	engine_list_head = e->next;
	177	if (engine_list_tail == e)
	178	engine_list_tail = e->prev;
	179	engine_free_util(e, 0);
	180	return 1;
	181	}
5270e702 RL	182
	183	/* Get the first/last "ENGINE" type available. */
	184	ENGINE *ENGINE_get_first(void)
0f113f3e MC	185	{
0f113f3e MC	186	ENGINE *ret;
5270e702	187
0f113f3e MC	188	CRYPTO_w_lock(CRYPTO_LOCK_ENGINE);
	189	ret = engine_list_head;
	190	if (ret) {
	191	ret->struct_ref++;
	192	engine_ref_debug(ret, 0, 1)
	193	}
	194	CRYPTO_w_unlock(CRYPTO_LOCK_ENGINE);
	195	return ret;
	196	}
b6d1e52d	197
5270e702	198	ENGINE *ENGINE_get_last(void)
0f113f3e MC	199	{
0f113f3e MC	200	ENGINE *ret;
5270e702	201
0f113f3e MC	202	CRYPTO_w_lock(CRYPTO_LOCK_ENGINE);
	203	ret = engine_list_tail;
	204	if (ret) {
	205	ret->struct_ref++;
	206	engine_ref_debug(ret, 0, 1)
	207	}
	208	CRYPTO_w_unlock(CRYPTO_LOCK_ENGINE);
	209	return ret;
	210	}
5270e702 RL	211
	212	/* Iterate to the next/previous "ENGINE" type (NULL = end of the list). */
	213	ENGINE ENGINE_get_next(ENGINE e)
0f113f3e MC	214	{
	215	ENGINE *ret = NULL;
	216	if (e == NULL) {
	217	ENGINEerr(ENGINE_F_ENGINE_GET_NEXT, ERR_R_PASSED_NULL_PARAMETER);
	218	return 0;
	219	}
	220	CRYPTO_w_lock(CRYPTO_LOCK_ENGINE);
	221	ret = e->next;
	222	if (ret) {
	223	/* Return a valid structural refernce to the next ENGINE */
	224	ret->struct_ref++;
	225	engine_ref_debug(ret, 0, 1)
	226	}
	227	CRYPTO_w_unlock(CRYPTO_LOCK_ENGINE);
	228	/* Release the structural reference to the previous ENGINE */
	229	ENGINE_free(e);
	230	return ret;
	231	}
b6d1e52d	232
5270e702	233	ENGINE ENGINE_get_prev(ENGINE e)
0f113f3e MC	234	{
	235	ENGINE *ret = NULL;
	236	if (e == NULL) {
	237	ENGINEerr(ENGINE_F_ENGINE_GET_PREV, ERR_R_PASSED_NULL_PARAMETER);
	238	return 0;
	239	}
	240	CRYPTO_w_lock(CRYPTO_LOCK_ENGINE);
	241	ret = e->prev;
	242	if (ret) {
	243	/* Return a valid structural reference to the next ENGINE */
	244	ret->struct_ref++;
	245	engine_ref_debug(ret, 0, 1)
	246	}
	247	CRYPTO_w_unlock(CRYPTO_LOCK_ENGINE);
	248	/* Release the structural reference to the previous ENGINE */
	249	ENGINE_free(e);
	250	return ret;
	251	}
5270e702 RL	252
	253	/* Add another "ENGINE" type into the list. */
	254	int ENGINE_add(ENGINE *e)
0f113f3e MC	255	{
	256	int to_return = 1;
	257	if (e == NULL) {
	258	ENGINEerr(ENGINE_F_ENGINE_ADD, ERR_R_PASSED_NULL_PARAMETER);
	259	return 0;
	260	}
	261	if ((e->id == NULL) \|\| (e->name == NULL)) {
	262	ENGINEerr(ENGINE_F_ENGINE_ADD, ENGINE_R_ID_OR_NAME_MISSING);
5850cc75	263	return 0;
0f113f3e MC	264	}
	265	CRYPTO_w_lock(CRYPTO_LOCK_ENGINE);
	266	if (!engine_list_add(e)) {
	267	ENGINEerr(ENGINE_F_ENGINE_ADD, ENGINE_R_INTERNAL_LIST_ERROR);
	268	to_return = 0;
	269	}
	270	CRYPTO_w_unlock(CRYPTO_LOCK_ENGINE);
	271	return to_return;
	272	}
5270e702 RL	273
	274	/* Remove an existing "ENGINE" type from the array. */
	275	int ENGINE_remove(ENGINE *e)
0f113f3e MC	276	{
	277	int to_return = 1;
	278	if (e == NULL) {
	279	ENGINEerr(ENGINE_F_ENGINE_REMOVE, ERR_R_PASSED_NULL_PARAMETER);
	280	return 0;
	281	}
	282	CRYPTO_w_lock(CRYPTO_LOCK_ENGINE);
	283	if (!engine_list_remove(e)) {
	284	ENGINEerr(ENGINE_F_ENGINE_REMOVE, ENGINE_R_INTERNAL_LIST_ERROR);
	285	to_return = 0;
	286	}
	287	CRYPTO_w_unlock(CRYPTO_LOCK_ENGINE);
	288	return to_return;
	289	}
5270e702	290
b6d1e52d	291	static void engine_cpy(ENGINE dest, const ENGINE src)
0f113f3e MC	292	{
	293	dest->id = src->id;
	294	dest->name = src->name;
b6d1e52d	295	#ifndef OPENSSL_NO_RSA
0f113f3e	296	dest->rsa_meth = src->rsa_meth;
b6d1e52d GT	297	#endif
b6d1e52d GT	298	#ifndef OPENSSL_NO_DSA
0f113f3e	299	dest->dsa_meth = src->dsa_meth;
b6d1e52d GT	300	#endif
b6d1e52d GT	301	#ifndef OPENSSL_NO_DH
0f113f3e	302	dest->dh_meth = src->dh_meth;
4d94ae00	303	#endif
10bf4fc2	304	#ifndef OPENSSL_NO_EC
0f113f3e	305	dest->ecdh_meth = src->ecdh_meth;
0f113f3e	306	dest->ecdsa_meth = src->ecdsa_meth;
b6d1e52d	307	#endif
0f113f3e MC	308	dest->rand_meth = src->rand_meth;
	309	dest->store_meth = src->store_meth;
	310	dest->ciphers = src->ciphers;
	311	dest->digests = src->digests;
	312	dest->pkey_meths = src->pkey_meths;
	313	dest->destroy = src->destroy;
	314	dest->init = src->init;
	315	dest->finish = src->finish;
	316	dest->ctrl = src->ctrl;
	317	dest->load_privkey = src->load_privkey;
	318	dest->load_pubkey = src->load_pubkey;
	319	dest->cmd_defns = src->cmd_defns;
	320	dest->flags = src->flags;
	321	}
b6d1e52d	322
5270e702	323	ENGINE ENGINE_by_id(const char id)
0f113f3e MC	324	{
	325	ENGINE *iterator;
	326	char *load_dir = NULL;
	327	if (id == NULL) {
	328	ENGINEerr(ENGINE_F_ENGINE_BY_ID, ERR_R_PASSED_NULL_PARAMETER);
	329	return NULL;
	330	}
	331	CRYPTO_w_lock(CRYPTO_LOCK_ENGINE);
	332	iterator = engine_list_head;
	333	while (iterator && (strcmp(id, iterator->id) != 0))
	334	iterator = iterator->next;
90945fa3	335	if (iterator != NULL) {
0f113f3e MC	336	/*
	337	* We need to return a structural reference. If this is an ENGINE
	338	* type that returns copies, make a duplicate - otherwise increment
	339	* the existing ENGINE's reference count.
	340	*/
	341	if (iterator->flags & ENGINE_FLAGS_BY_ID_COPY) {
	342	ENGINE *cp = ENGINE_new();
90945fa3	343	if (cp == NULL)
0f113f3e MC	344	iterator = NULL;
	345	else {
	346	engine_cpy(cp, iterator);
	347	iterator = cp;
	348	}
	349	} else {
	350	iterator->struct_ref++;
	351	engine_ref_debug(iterator, 0, 1)
	352	}
	353	}
	354	CRYPTO_w_unlock(CRYPTO_LOCK_ENGINE);
90945fa3	355	if (iterator != NULL)
0f113f3e MC	356	return iterator;
	357	/*
	358	* Prevent infinite recusrion if we're looking for the dynamic engine.
	359	*/
	360	if (strcmp(id, "dynamic")) {
	361	# ifdef OPENSSL_SYS_VMS
	362	if ((load_dir = getenv("OPENSSL_ENGINES")) == 0)
	363	load_dir = "SSLROOT:[ENGINES]";
	364	# else
	365	if ((load_dir = getenv("OPENSSL_ENGINES")) == 0)
	366	load_dir = ENGINESDIR;
	367	# endif
	368	iterator = ENGINE_by_id("dynamic");
	369	if (!iterator \|\| !ENGINE_ctrl_cmd_string(iterator, "ID", id, 0) \|\|
	370	!ENGINE_ctrl_cmd_string(iterator, "DIR_LOAD", "2", 0) \|\|
	371	!ENGINE_ctrl_cmd_string(iterator, "DIR_ADD",
	372	load_dir, 0) \|\|
	373	!ENGINE_ctrl_cmd_string(iterator, "LIST_ADD", "1", 0) \|\|
	374	!ENGINE_ctrl_cmd_string(iterator, "LOAD", NULL, 0))
	375	goto notfound;
	376	return iterator;
	377	}
	378	notfound:
	379	ENGINE_free(iterator);
	380	ENGINEerr(ENGINE_F_ENGINE_BY_ID, ENGINE_R_NO_SUCH_ENGINE);
	381	ERR_add_error_data(2, "id=", id);
	382	return NULL;
	383	/* EEK! Experimental code ends */
0f113f3e	384	}
314c6670 GT	385
314c6670 GT	386	int ENGINE_up_ref(ENGINE *e)
0f113f3e MC	387	{
	388	if (e == NULL) {
	389	ENGINEerr(ENGINE_F_ENGINE_UP_REF, ERR_R_PASSED_NULL_PARAMETER);
	390	return 0;
	391	}
	392	CRYPTO_add(&e->struct_ref, 1, CRYPTO_LOCK_ENGINE);
	393	return 1;
	394	}