1 /* crypto/engine/eng_list.c */
2 /* Written by Geoff Thorpe (geoff@geoffthorpe.net) for the OpenSSL
5 /* ====================================================================
6 * Copyright (c) 1999-2001 The OpenSSL Project. All rights reserved.
8 * Redistribution and use in source and binary forms, with or without
9 * modification, are permitted provided that the following conditions
12 * 1. Redistributions of source code must retain the above copyright
13 * notice, this list of conditions and the following disclaimer.
15 * 2. Redistributions in binary form must reproduce the above copyright
16 * notice, this list of conditions and the following disclaimer in
17 * the documentation and/or other materials provided with the
20 * 3. All advertising materials mentioning features or use of this
21 * software must display the following acknowledgment:
22 * "This product includes software developed by the OpenSSL Project
23 * for use in the OpenSSL Toolkit. (http://www.OpenSSL.org/)"
25 * 4. The names "OpenSSL Toolkit" and "OpenSSL Project" must not be used to
26 * endorse or promote products derived from this software without
27 * prior written permission. For written permission, please contact
28 * licensing@OpenSSL.org.
30 * 5. Products derived from this software may not be called "OpenSSL"
31 * nor may "OpenSSL" appear in their names without prior written
32 * permission of the OpenSSL Project.
34 * 6. Redistributions of any form whatsoever must retain the following
36 * "This product includes software developed by the OpenSSL Project
37 * for use in the OpenSSL Toolkit (http://www.OpenSSL.org/)"
39 * THIS SOFTWARE IS PROVIDED BY THE OpenSSL PROJECT ``AS IS'' AND ANY
40 * EXPRESSED OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
41 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR
42 * PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE OpenSSL PROJECT OR
43 * ITS CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
44 * SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT
45 * NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES;
46 * LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
47 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT,
48 * STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE)
49 * ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED
50 * OF THE POSSIBILITY OF SUCH DAMAGE.
51 * ====================================================================
53 * This product includes cryptographic software written by Eric Young
54 * (eay@cryptsoft.com). This product includes software written by Tim
55 * Hudson (tjh@cryptsoft.com).
59 #include <openssl/crypto.h>
62 #include <openssl/engine.h>
64 /* The linked-list of pointers to engine types. engine_list_head
65 * incorporates an implicit structural reference but engine_list_tail
66 * does not - the latter is a computational niceity and only points
67 * to something that is already pointed to by its predecessor in the
68 * list (or engine_list_head itself). In the same way, the use of the
69 * "prev" pointer in each ENGINE is to save excessive list iteration,
70 * it doesn't correspond to an extra structural reference. Hence,
71 * engine_list_head, and each non-null "next" pointer account for
72 * the list itself assuming exactly 1 structural reference on each
74 static ENGINE *engine_list_head = NULL;
75 static ENGINE *engine_list_tail = NULL;
77 /* This cleanup function is only needed internally. If it should be called, we
78 * register it with the "ENGINE_cleanup()" stack to be called during cleanup. */
80 static void engine_list_cleanup(void)
82 ENGINE *iterator = engine_list_head;
84 while(iterator != NULL)
86 ENGINE_remove(iterator);
87 iterator = engine_list_head;
92 /* These static functions starting with a lower case "engine_" always
93 * take place when CRYPTO_LOCK_ENGINE has been locked up. */
94 static int engine_list_add(ENGINE *e)
97 ENGINE *iterator = NULL;
101 ENGINEerr(ENGINE_F_ENGINE_LIST_ADD,
102 ERR_R_PASSED_NULL_PARAMETER);
105 iterator = engine_list_head;
106 while(iterator && !conflict)
108 conflict = (strcmp(iterator->id, e->id) == 0);
109 iterator = iterator->next;
113 ENGINEerr(ENGINE_F_ENGINE_LIST_ADD,
114 ENGINE_R_CONFLICTING_ENGINE_ID);
117 if(engine_list_head == NULL)
119 /* We are adding to an empty list. */
122 ENGINEerr(ENGINE_F_ENGINE_LIST_ADD,
123 ENGINE_R_INTERNAL_LIST_ERROR);
126 engine_list_head = e;
128 /* The first time the list allocates, we should register the
130 engine_cleanup_add_last(engine_list_cleanup);
134 /* We are adding to the tail of an existing list. */
135 if((engine_list_tail == NULL) ||
136 (engine_list_tail->next != NULL))
138 ENGINEerr(ENGINE_F_ENGINE_LIST_ADD,
139 ENGINE_R_INTERNAL_LIST_ERROR);
142 engine_list_tail->next = e;
143 e->prev = engine_list_tail;
145 /* Having the engine in the list assumes a structural
148 engine_ref_debug(e, 0, 1)
149 /* However it came to be, e is the last item in the list. */
150 engine_list_tail = e;
155 static int engine_list_remove(ENGINE *e)
161 ENGINEerr(ENGINE_F_ENGINE_LIST_REMOVE,
162 ERR_R_PASSED_NULL_PARAMETER);
165 /* We need to check that e is in our linked list! */
166 iterator = engine_list_head;
167 while(iterator && (iterator != e))
168 iterator = iterator->next;
171 ENGINEerr(ENGINE_F_ENGINE_LIST_REMOVE,
172 ENGINE_R_ENGINE_IS_NOT_IN_LIST);
175 /* un-link e from the chain. */
177 e->next->prev = e->prev;
179 e->prev->next = e->next;
180 /* Correct our head/tail if necessary. */
181 if(engine_list_head == e)
182 engine_list_head = e->next;
183 if(engine_list_tail == e)
184 engine_list_tail = e->prev;
185 engine_free_util(e, 0);
189 /* Get the first/last "ENGINE" type available. */
190 ENGINE *ENGINE_get_first(void)
194 CRYPTO_r_lock(CRYPTO_LOCK_ENGINE);
195 ret = engine_list_head;
199 engine_ref_debug(ret, 0, 1)
201 CRYPTO_r_unlock(CRYPTO_LOCK_ENGINE);
205 ENGINE *ENGINE_get_last(void)
209 CRYPTO_r_lock(CRYPTO_LOCK_ENGINE);
210 ret = engine_list_tail;
214 engine_ref_debug(ret, 0, 1)
216 CRYPTO_r_unlock(CRYPTO_LOCK_ENGINE);
220 /* Iterate to the next/previous "ENGINE" type (NULL = end of the list). */
221 ENGINE *ENGINE_get_next(ENGINE *e)
226 ENGINEerr(ENGINE_F_ENGINE_GET_NEXT,
227 ERR_R_PASSED_NULL_PARAMETER);
230 CRYPTO_r_lock(CRYPTO_LOCK_ENGINE);
234 /* Return a valid structural refernce to the next ENGINE */
236 engine_ref_debug(ret, 0, 1)
238 CRYPTO_r_unlock(CRYPTO_LOCK_ENGINE);
239 /* Release the structural reference to the previous ENGINE */
244 ENGINE *ENGINE_get_prev(ENGINE *e)
249 ENGINEerr(ENGINE_F_ENGINE_GET_PREV,
250 ERR_R_PASSED_NULL_PARAMETER);
253 CRYPTO_r_lock(CRYPTO_LOCK_ENGINE);
257 /* Return a valid structural reference to the next ENGINE */
259 engine_ref_debug(ret, 0, 1)
261 CRYPTO_r_unlock(CRYPTO_LOCK_ENGINE);
262 /* Release the structural reference to the previous ENGINE */
267 /* Add another "ENGINE" type into the list. */
268 int ENGINE_add(ENGINE *e)
273 ENGINEerr(ENGINE_F_ENGINE_ADD,
274 ERR_R_PASSED_NULL_PARAMETER);
277 if((e->id == NULL) || (e->name == NULL))
279 ENGINEerr(ENGINE_F_ENGINE_ADD,
280 ENGINE_R_ID_OR_NAME_MISSING);
282 CRYPTO_w_lock(CRYPTO_LOCK_ENGINE);
283 if(!engine_list_add(e))
285 ENGINEerr(ENGINE_F_ENGINE_ADD,
286 ENGINE_R_INTERNAL_LIST_ERROR);
289 CRYPTO_w_unlock(CRYPTO_LOCK_ENGINE);
293 /* Remove an existing "ENGINE" type from the array. */
294 int ENGINE_remove(ENGINE *e)
299 ENGINEerr(ENGINE_F_ENGINE_REMOVE,
300 ERR_R_PASSED_NULL_PARAMETER);
303 CRYPTO_w_lock(CRYPTO_LOCK_ENGINE);
304 if(!engine_list_remove(e))
306 ENGINEerr(ENGINE_F_ENGINE_REMOVE,
307 ENGINE_R_INTERNAL_LIST_ERROR);
310 CRYPTO_w_unlock(CRYPTO_LOCK_ENGINE);
314 static void engine_cpy(ENGINE *dest, const ENGINE *src)
317 dest->name = src->name;
318 #ifndef OPENSSL_NO_RSA
319 dest->rsa_meth = src->rsa_meth;
321 #ifndef OPENSSL_NO_DSA
322 dest->dsa_meth = src->dsa_meth;
324 #ifndef OPENSSL_NO_DH
325 dest->dh_meth = src->dh_meth;
327 dest->rand_meth = src->rand_meth;
328 dest->ciphers = src->ciphers;
329 dest->digests = src->digests;
330 dest->destroy = src->destroy;
331 dest->init = src->init;
332 dest->finish = src->finish;
333 dest->ctrl = src->ctrl;
334 dest->load_privkey = src->load_privkey;
335 dest->load_pubkey = src->load_pubkey;
336 dest->cmd_defns = src->cmd_defns;
337 dest->flags = src->flags;
340 ENGINE *ENGINE_by_id(const char *id)
345 ENGINEerr(ENGINE_F_ENGINE_BY_ID,
346 ERR_R_PASSED_NULL_PARAMETER);
349 CRYPTO_r_lock(CRYPTO_LOCK_ENGINE);
350 iterator = engine_list_head;
351 while(iterator && (strcmp(id, iterator->id) != 0))
352 iterator = iterator->next;
355 /* We need to return a structural reference. If this is an
356 * ENGINE type that returns copies, make a duplicate - otherwise
357 * increment the existing ENGINE's reference count. */
358 if(iterator->flags & ENGINE_FLAGS_BY_ID_COPY)
360 ENGINE *cp = ENGINE_new();
365 engine_cpy(cp, iterator);
371 iterator->struct_ref++;
372 engine_ref_debug(iterator, 0, 1)
375 CRYPTO_r_unlock(CRYPTO_LOCK_ENGINE);
377 ENGINEerr(ENGINE_F_ENGINE_BY_ID,
378 ENGINE_R_NO_SUCH_ENGINE);