1 /* $OpenBSD: eng_list.c,v 1.20 2015/06/19 06:32:43 bcook Exp $ */
2 /* Written by Geoff Thorpe (geoff@geoffthorpe.net) for the OpenSSL
3  * project 2000.
4  */
5 /* ====================================================================
6  * Copyright (c) 1999-2001 The OpenSSL Project.  All rights reserved.
7  *
8  * Redistribution and use in source and binary forms, with or without
9  * modification, are permitted provided that the following conditions
10  * are met:
11  *
12  * 1. Redistributions of source code must retain the above copyright
13  *    notice, this list of conditions and the following disclaimer.
14  *
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
18  *    distribution.
19  *
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/)"
24  *
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.
29  *
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.
33  *
34  * 6. Redistributions of any form whatsoever must retain the following
35  *    acknowledgment:
36  *    "This product includes software developed by the OpenSSL Project
37  *    for use in the OpenSSL Toolkit (http://www.OpenSSL.org/)"
38  *
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  * ====================================================================
52  *
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).
56  *
57  */
58 /* ====================================================================
59  * Copyright 2002 Sun Microsystems, Inc. ALL RIGHTS RESERVED.
60  * ECDH support in OpenSSL originally developed by
61  * SUN MICROSYSTEMS, INC., and contributed to the OpenSSL project.
62  */
63 
64 #include <string.h>
65 #include <unistd.h>
66 
67 #include <openssl/opensslconf.h>
68 
69 #include <openssl/err.h>
70 
71 #include "cryptlib.h"
72 #include "eng_int.h"
73 
74 /* The linked-list of pointers to engine types. engine_list_head
75  * incorporates an implicit structural reference but engine_list_tail
76  * does not - the latter is a computational niceity and only points
77  * to something that is already pointed to by its predecessor in the
78  * list (or engine_list_head itself). In the same way, the use of the
79  * "prev" pointer in each ENGINE is to save excessive list iteration,
80  * it doesn't correspond to an extra structural reference. Hence,
81  * engine_list_head, and each non-null "next" pointer account for
82  * the list itself assuming exactly 1 structural reference on each
83  * list member. */
84 static ENGINE *engine_list_head = NULL;
85 static ENGINE *engine_list_tail = NULL;
86 
87 /* This cleanup function is only needed internally. If it should be called, we
88  * register it with the "ENGINE_cleanup()" stack to be called during cleanup. */
89 
90 static void
91 engine_list_cleanup(void)
92 {
93 	ENGINE *iterator = engine_list_head;
94 
95 	while (iterator != NULL && ENGINE_remove(iterator))
96 		iterator = engine_list_head;
97 }
98 
99 /* These static functions starting with a lower case "engine_" always
100  * take place when CRYPTO_LOCK_ENGINE has been locked up. */
101 static int
102 engine_list_add(ENGINE *e)
103 {
104 	int conflict = 0;
105 	ENGINE *iterator = NULL;
106 
107 	if (e == NULL) {
108 		ENGINEerr(ENGINE_F_ENGINE_LIST_ADD,
109 		    ERR_R_PASSED_NULL_PARAMETER);
110 		return 0;
111 	}
112 	iterator = engine_list_head;
113 	while (iterator && !conflict) {
114 		conflict = (strcmp(iterator->id, e->id) == 0);
115 		iterator = iterator->next;
116 	}
117 	if (conflict) {
118 		ENGINEerr(ENGINE_F_ENGINE_LIST_ADD,
119 		    ENGINE_R_CONFLICTING_ENGINE_ID);
120 		return 0;
121 	}
122 	if (engine_list_head == NULL) {
123 		/* We are adding to an empty list. */
124 		if (engine_list_tail) {
125 			ENGINEerr(ENGINE_F_ENGINE_LIST_ADD,
126 			    ENGINE_R_INTERNAL_LIST_ERROR);
127 			return 0;
128 		}
129 		engine_list_head = e;
130 		e->prev = NULL;
131 		/* The first time the list allocates, we should register the
132 		 * cleanup. */
133 		engine_cleanup_add_last(engine_list_cleanup);
134 	} else {
135 		/* We are adding to the tail of an existing list. */
136 		if ((engine_list_tail == NULL) ||
137 		    (engine_list_tail->next != NULL)) {
138 			ENGINEerr(ENGINE_F_ENGINE_LIST_ADD,
139 			    ENGINE_R_INTERNAL_LIST_ERROR);
140 			return 0;
141 		}
142 		engine_list_tail->next = e;
143 		e->prev = engine_list_tail;
144 	}
145 	/* Having the engine in the list assumes a structural
146 	 * reference. */
147 	e->struct_ref++;
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;
151 	e->next = NULL;
152 	return 1;
153 }
154 
155 static int
156 engine_list_remove(ENGINE *e)
157 {
158 	ENGINE *iterator;
159 
160 	if (e == NULL) {
161 		ENGINEerr(ENGINE_F_ENGINE_LIST_REMOVE,
162 		    ERR_R_PASSED_NULL_PARAMETER);
163 		return 0;
164 	}
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;
169 	if (iterator == NULL) {
170 		ENGINEerr(ENGINE_F_ENGINE_LIST_REMOVE,
171 		    ENGINE_R_ENGINE_IS_NOT_IN_LIST);
172 		return 0;
173 	}
174 	/* un-link e from the chain. */
175 	if (e->next)
176 		e->next->prev = e->prev;
177 	if (e->prev)
178 		e->prev->next = e->next;
179 	/* Correct our head/tail if necessary. */
180 	if (engine_list_head == e)
181 		engine_list_head = e->next;
182 	if (engine_list_tail == e)
183 		engine_list_tail = e->prev;
184 	engine_free_util(e, 0);
185 	return 1;
186 }
187 
188 /* Get the first/last "ENGINE" type available. */
189 ENGINE *
190 ENGINE_get_first(void)
191 {
192 	ENGINE *ret;
193 
194 	CRYPTO_w_lock(CRYPTO_LOCK_ENGINE);
195 	ret = engine_list_head;
196 	if (ret) {
197 		ret->struct_ref++;
198 		engine_ref_debug(ret, 0, 1)
199 	}
200 	CRYPTO_w_unlock(CRYPTO_LOCK_ENGINE);
201 	return ret;
202 }
203 
204 ENGINE *
205 ENGINE_get_last(void)
206 {
207 	ENGINE *ret;
208 
209 	CRYPTO_w_lock(CRYPTO_LOCK_ENGINE);
210 	ret = engine_list_tail;
211 	if (ret) {
212 		ret->struct_ref++;
213 		engine_ref_debug(ret, 0, 1)
214 	}
215 	CRYPTO_w_unlock(CRYPTO_LOCK_ENGINE);
216 	return ret;
217 }
218 
219 /* Iterate to the next/previous "ENGINE" type (NULL = end of the list). */
220 ENGINE *
221 ENGINE_get_next(ENGINE *e)
222 {
223 	ENGINE *ret = NULL;
224 
225 	if (e == NULL) {
226 		ENGINEerr(ENGINE_F_ENGINE_GET_NEXT,
227 		    ERR_R_PASSED_NULL_PARAMETER);
228 		return 0;
229 	}
230 	CRYPTO_w_lock(CRYPTO_LOCK_ENGINE);
231 	ret = e->next;
232 	if (ret) {
233 		/* Return a valid structural refernce to the next ENGINE */
234 		ret->struct_ref++;
235 		engine_ref_debug(ret, 0, 1)
236 	}
237 	CRYPTO_w_unlock(CRYPTO_LOCK_ENGINE);
238 	/* Release the structural reference to the previous ENGINE */
239 	ENGINE_free(e);
240 	return ret;
241 }
242 
243 ENGINE *
244 ENGINE_get_prev(ENGINE *e)
245 {
246 	ENGINE *ret = NULL;
247 
248 	if (e == NULL) {
249 		ENGINEerr(ENGINE_F_ENGINE_GET_PREV,
250 		    ERR_R_PASSED_NULL_PARAMETER);
251 		return 0;
252 	}
253 	CRYPTO_w_lock(CRYPTO_LOCK_ENGINE);
254 	ret = e->prev;
255 	if (ret) {
256 		/* Return a valid structural reference to the next ENGINE */
257 		ret->struct_ref++;
258 		engine_ref_debug(ret, 0, 1)
259 	}
260 	CRYPTO_w_unlock(CRYPTO_LOCK_ENGINE);
261 	/* Release the structural reference to the previous ENGINE */
262 	ENGINE_free(e);
263 	return ret;
264 }
265 
266 /* Add another "ENGINE" type into the list. */
267 int
268 ENGINE_add(ENGINE *e)
269 {
270 	int to_return = 1;
271 
272 	if (e == NULL) {
273 		ENGINEerr(ENGINE_F_ENGINE_ADD,
274 		    ERR_R_PASSED_NULL_PARAMETER);
275 		return 0;
276 	}
277 	if ((e->id == NULL) || (e->name == NULL)) {
278 		ENGINEerr(ENGINE_F_ENGINE_ADD,
279 		    ENGINE_R_ID_OR_NAME_MISSING);
280 	}
281 	CRYPTO_w_lock(CRYPTO_LOCK_ENGINE);
282 	if (!engine_list_add(e)) {
283 		ENGINEerr(ENGINE_F_ENGINE_ADD,
284 		    ENGINE_R_INTERNAL_LIST_ERROR);
285 		to_return = 0;
286 	}
287 	CRYPTO_w_unlock(CRYPTO_LOCK_ENGINE);
288 	return to_return;
289 }
290 
291 /* Remove an existing "ENGINE" type from the array. */
292 int
293 ENGINE_remove(ENGINE *e)
294 {
295 	int to_return = 1;
296 
297 	if (e == NULL) {
298 		ENGINEerr(ENGINE_F_ENGINE_REMOVE,
299 		    ERR_R_PASSED_NULL_PARAMETER);
300 		return 0;
301 	}
302 	CRYPTO_w_lock(CRYPTO_LOCK_ENGINE);
303 	if (!engine_list_remove(e)) {
304 		ENGINEerr(ENGINE_F_ENGINE_REMOVE,
305 		    ENGINE_R_INTERNAL_LIST_ERROR);
306 		to_return = 0;
307 	}
308 	CRYPTO_w_unlock(CRYPTO_LOCK_ENGINE);
309 	return to_return;
310 }
311 
312 static void
313 engine_cpy(ENGINE *dest, const ENGINE *src)
314 {
315 	dest->id = src->id;
316 	dest->name = src->name;
317 #ifndef OPENSSL_NO_RSA
318 	dest->rsa_meth = src->rsa_meth;
319 #endif
320 #ifndef OPENSSL_NO_DSA
321 	dest->dsa_meth = src->dsa_meth;
322 #endif
323 #ifndef OPENSSL_NO_DH
324 	dest->dh_meth = src->dh_meth;
325 #endif
326 #ifndef OPENSSL_NO_ECDH
327 	dest->ecdh_meth = src->ecdh_meth;
328 #endif
329 #ifndef OPENSSL_NO_ECDSA
330 	dest->ecdsa_meth = src->ecdsa_meth;
331 #endif
332 	dest->rand_meth = src->rand_meth;
333 	dest->store_meth = src->store_meth;
334 	dest->ciphers = src->ciphers;
335 	dest->digests = src->digests;
336 	dest->pkey_meths = src->pkey_meths;
337 	dest->destroy = src->destroy;
338 	dest->init = src->init;
339 	dest->finish = src->finish;
340 	dest->ctrl = src->ctrl;
341 	dest->load_privkey = src->load_privkey;
342 	dest->load_pubkey = src->load_pubkey;
343 	dest->cmd_defns = src->cmd_defns;
344 	dest->flags = src->flags;
345 }
346 
347 ENGINE *
348 ENGINE_by_id(const char *id)
349 {
350 	ENGINE *iterator;
351 
352 	if (id == NULL) {
353 		ENGINEerr(ENGINE_F_ENGINE_BY_ID,
354 		    ERR_R_PASSED_NULL_PARAMETER);
355 		return NULL;
356 	}
357 	CRYPTO_w_lock(CRYPTO_LOCK_ENGINE);
358 	iterator = engine_list_head;
359 	while (iterator && (strcmp(id, iterator->id) != 0))
360 		iterator = iterator->next;
361 	if (iterator) {
362 		/* We need to return a structural reference. If this is an
363 		 * ENGINE type that returns copies, make a duplicate - otherwise
364 		 * increment the existing ENGINE's reference count. */
365 		if (iterator->flags & ENGINE_FLAGS_BY_ID_COPY) {
366 			ENGINE *cp = ENGINE_new();
367 			if (!cp)
368 				iterator = NULL;
369 			else {
370 				engine_cpy(cp, iterator);
371 				iterator = cp;
372 			}
373 		} else {
374 			iterator->struct_ref++;
375 			engine_ref_debug(iterator, 0, 1)
376 		}
377 	}
378 	CRYPTO_w_unlock(CRYPTO_LOCK_ENGINE);
379 
380 	if (iterator == NULL) {
381 		ENGINEerr(ENGINE_F_ENGINE_BY_ID, ENGINE_R_NO_SUCH_ENGINE);
382 		ERR_asprintf_error_data("id=%s", id);
383 	}
384 	return iterator;
385 }
386 
387 int
388 ENGINE_up_ref(ENGINE *e)
389 {
390 	if (e == NULL) {
391 		ENGINEerr(ENGINE_F_ENGINE_UP_REF, ERR_R_PASSED_NULL_PARAMETER);
392 		return 0;
393 	}
394 	CRYPTO_add(&e->struct_ref, 1, CRYPTO_LOCK_ENGINE);
395 	return 1;
396 }
397