1 /*
2 * Copyright 2001-2023 The OpenSSL Project Authors. All Rights Reserved.
3 * Copyright (c) 2002, Oracle and/or its affiliates. All rights reserved
4 *
5 * Licensed under the Apache License 2.0 (the "License"). You may not use
6 * this file except in compliance with the License. You can obtain a copy
7 * in the file LICENSE in the source distribution or at
8 * https://www.openssl.org/source/license.html
9 */
10
11 /* We need to use some engine deprecated APIs */
12 #define OPENSSL_SUPPRESS_DEPRECATED
13
14 #include "eng_local.h"
15
16 /*
17 * The linked-list of pointers to engine types. engine_list_head incorporates
18 * an implicit structural reference but engine_list_tail does not - the
19 * latter is a computational optimization and only points to something that
20 * is already pointed to by its predecessor in the list (or engine_list_head
21 * itself). In the same way, the use of the "prev" pointer in each ENGINE is
22 * to save excessive list iteration, it doesn't correspond to an extra
23 * structural reference. Hence, engine_list_head, and each non-null "next"
24 * pointer account for the list itself assuming exactly 1 structural
25 * reference on each list member.
26 */
27 static ENGINE *engine_list_head = NULL;
28 static ENGINE *engine_list_tail = NULL;
29
30 /*
31 * The linked list of currently loaded dynamic engines.
32 */
33 static ENGINE *engine_dyn_list_head = NULL;
34 static ENGINE *engine_dyn_list_tail = NULL;
35
36 /*
37 * This cleanup function is only needed internally. If it should be called,
38 * we register it with the "engine_cleanup_int()" stack to be called during
39 * cleanup.
40 */
41
engine_list_cleanup(void)42 static void engine_list_cleanup(void)
43 {
44 ENGINE *iterator = engine_list_head;
45
46 while (iterator != NULL) {
47 ENGINE_remove(iterator);
48 iterator = engine_list_head;
49 }
50 return;
51 }
52
53 /*
54 * These static functions starting with a lower case "engine_" always take
55 * place when global_engine_lock has been locked up.
56 */
engine_list_add(ENGINE * e)57 static int engine_list_add(ENGINE *e)
58 {
59 int conflict = 0;
60 ENGINE *iterator = NULL;
61 int ref;
62
63 if (e == NULL) {
64 ERR_raise(ERR_LIB_ENGINE, ERR_R_PASSED_NULL_PARAMETER);
65 return 0;
66 }
67 iterator = engine_list_head;
68 while (iterator && !conflict) {
69 conflict = (strcmp(iterator->id, e->id) == 0);
70 iterator = iterator->next;
71 }
72 if (conflict) {
73 ERR_raise(ERR_LIB_ENGINE, ENGINE_R_CONFLICTING_ENGINE_ID);
74 return 0;
75 }
76
77 /*
78 * Having the engine in the list assumes a structural reference.
79 */
80 if (!CRYPTO_UP_REF(&e->struct_ref, &ref)) {
81 ERR_raise(ERR_LIB_ENGINE, ENGINE_R_INTERNAL_LIST_ERROR);
82 return 0;
83 }
84 ENGINE_REF_PRINT(e, 0, 1);
85 if (engine_list_head == NULL) {
86 /* We are adding to an empty list. */
87 if (engine_list_tail != NULL) {
88 CRYPTO_DOWN_REF(&e->struct_ref, &ref);
89 ERR_raise(ERR_LIB_ENGINE, ENGINE_R_INTERNAL_LIST_ERROR);
90 return 0;
91 }
92 /*
93 * The first time the list allocates, we should register the cleanup.
94 */
95 if (!engine_cleanup_add_last(engine_list_cleanup)) {
96 CRYPTO_DOWN_REF(&e->struct_ref, &ref);
97 ERR_raise(ERR_LIB_ENGINE, ENGINE_R_INTERNAL_LIST_ERROR);
98 return 0;
99 }
100 engine_list_head = e;
101 e->prev = NULL;
102 } else {
103 /* We are adding to the tail of an existing list. */
104 if ((engine_list_tail == NULL) || (engine_list_tail->next != NULL)) {
105 CRYPTO_DOWN_REF(&e->struct_ref, &ref);
106 ERR_raise(ERR_LIB_ENGINE, ENGINE_R_INTERNAL_LIST_ERROR);
107 return 0;
108 }
109 engine_list_tail->next = e;
110 e->prev = engine_list_tail;
111 }
112
113 /* However it came to be, e is the last item in the list. */
114 engine_list_tail = e;
115 e->next = NULL;
116 return 1;
117 }
118
engine_list_remove(ENGINE * e)119 static int engine_list_remove(ENGINE *e)
120 {
121 ENGINE *iterator;
122
123 if (e == NULL) {
124 ERR_raise(ERR_LIB_ENGINE, ERR_R_PASSED_NULL_PARAMETER);
125 return 0;
126 }
127 /* We need to check that e is in our linked list! */
128 iterator = engine_list_head;
129 while (iterator && (iterator != e))
130 iterator = iterator->next;
131 if (iterator == NULL) {
132 ERR_raise(ERR_LIB_ENGINE, ENGINE_R_ENGINE_IS_NOT_IN_LIST);
133 return 0;
134 }
135 /* un-link e from the chain. */
136 if (e->next)
137 e->next->prev = e->prev;
138 if (e->prev)
139 e->prev->next = e->next;
140 /* Correct our head/tail if necessary. */
141 if (engine_list_head == e)
142 engine_list_head = e->next;
143 if (engine_list_tail == e)
144 engine_list_tail = e->prev;
145 engine_free_util(e, 0);
146 return 1;
147 }
148
149 /* Add engine to dynamic engine list. */
engine_add_dynamic_id(ENGINE * e,ENGINE_DYNAMIC_ID dynamic_id,int not_locked)150 int engine_add_dynamic_id(ENGINE *e, ENGINE_DYNAMIC_ID dynamic_id,
151 int not_locked)
152 {
153 int result = 0;
154 ENGINE *iterator = NULL;
155
156 if (e == NULL)
157 return 0;
158
159 if (e->dynamic_id == NULL && dynamic_id == NULL)
160 return 0;
161
162 if (not_locked && !CRYPTO_THREAD_write_lock(global_engine_lock))
163 return 0;
164
165 if (dynamic_id != NULL) {
166 iterator = engine_dyn_list_head;
167 while (iterator != NULL) {
168 if (iterator->dynamic_id == dynamic_id)
169 goto err;
170 iterator = iterator->next;
171 }
172 if (e->dynamic_id != NULL)
173 goto err;
174 e->dynamic_id = dynamic_id;
175 }
176
177 if (engine_dyn_list_head == NULL) {
178 /* We are adding to an empty list. */
179 if (engine_dyn_list_tail != NULL)
180 goto err;
181 engine_dyn_list_head = e;
182 e->prev_dyn = NULL;
183 } else {
184 /* We are adding to the tail of an existing list. */
185 if (engine_dyn_list_tail == NULL
186 || engine_dyn_list_tail->next_dyn != NULL)
187 goto err;
188 engine_dyn_list_tail->next_dyn = e;
189 e->prev_dyn = engine_dyn_list_tail;
190 }
191
192 engine_dyn_list_tail = e;
193 e->next_dyn = NULL;
194 result = 1;
195
196 err:
197 if (not_locked)
198 CRYPTO_THREAD_unlock(global_engine_lock);
199 return result;
200 }
201
202 /* Remove engine from dynamic engine list. */
engine_remove_dynamic_id(ENGINE * e,int not_locked)203 void engine_remove_dynamic_id(ENGINE *e, int not_locked)
204 {
205 if (e == NULL || e->dynamic_id == NULL)
206 return;
207
208 if (not_locked && !CRYPTO_THREAD_write_lock(global_engine_lock))
209 return;
210
211 e->dynamic_id = NULL;
212
213 /* un-link e from the chain. */
214 if (e->next_dyn != NULL)
215 e->next_dyn->prev_dyn = e->prev_dyn;
216 if (e->prev_dyn != NULL)
217 e->prev_dyn->next_dyn = e->next_dyn;
218 /* Correct our head/tail if necessary. */
219 if (engine_dyn_list_head == e)
220 engine_dyn_list_head = e->next_dyn;
221 if (engine_dyn_list_tail == e)
222 engine_dyn_list_tail = e->prev_dyn;
223
224 if (not_locked)
225 CRYPTO_THREAD_unlock(global_engine_lock);
226 }
227
228 /* Get the first/last "ENGINE" type available. */
ENGINE_get_first(void)229 ENGINE *ENGINE_get_first(void)
230 {
231 ENGINE *ret;
232
233 if (!RUN_ONCE(&engine_lock_init, do_engine_lock_init)) {
234 /* Maybe this should be raised in do_engine_lock_init() */
235 ERR_raise(ERR_LIB_ENGINE, ERR_R_CRYPTO_LIB);
236 return NULL;
237 }
238
239 if (!CRYPTO_THREAD_write_lock(global_engine_lock))
240 return NULL;
241 ret = engine_list_head;
242 if (ret) {
243 int ref;
244
245 if (!CRYPTO_UP_REF(&ret->struct_ref, &ref)) {
246 CRYPTO_THREAD_unlock(global_engine_lock);
247 ERR_raise(ERR_LIB_ENGINE, ERR_R_CRYPTO_LIB);
248 return NULL;
249 }
250 ENGINE_REF_PRINT(ret, 0, 1);
251 }
252 CRYPTO_THREAD_unlock(global_engine_lock);
253 return ret;
254 }
255
ENGINE_get_last(void)256 ENGINE *ENGINE_get_last(void)
257 {
258 ENGINE *ret;
259
260 if (!RUN_ONCE(&engine_lock_init, do_engine_lock_init)) {
261 /* Maybe this should be raised in do_engine_lock_init() */
262 ERR_raise(ERR_LIB_ENGINE, ERR_R_CRYPTO_LIB);
263 return NULL;
264 }
265
266 if (!CRYPTO_THREAD_write_lock(global_engine_lock))
267 return NULL;
268 ret = engine_list_tail;
269 if (ret) {
270 int ref;
271
272 if (!CRYPTO_UP_REF(&ret->struct_ref, &ref)) {
273 CRYPTO_THREAD_unlock(global_engine_lock);
274 ERR_raise(ERR_LIB_ENGINE, ERR_R_CRYPTO_LIB);
275 return NULL;
276 }
277 ENGINE_REF_PRINT(ret, 0, 1);
278 }
279 CRYPTO_THREAD_unlock(global_engine_lock);
280 return ret;
281 }
282
283 /* Iterate to the next/previous "ENGINE" type (NULL = end of the list). */
ENGINE_get_next(ENGINE * e)284 ENGINE *ENGINE_get_next(ENGINE *e)
285 {
286 ENGINE *ret = NULL;
287 if (e == NULL) {
288 ERR_raise(ERR_LIB_ENGINE, ERR_R_PASSED_NULL_PARAMETER);
289 return NULL;
290 }
291 if (!CRYPTO_THREAD_write_lock(global_engine_lock))
292 return NULL;
293 ret = e->next;
294 if (ret) {
295 int ref;
296
297 /* Return a valid structural reference to the next ENGINE */
298 if (!CRYPTO_UP_REF(&ret->struct_ref, &ref)) {
299 CRYPTO_THREAD_unlock(global_engine_lock);
300 ERR_raise(ERR_LIB_ENGINE, ERR_R_CRYPTO_LIB);
301 return NULL;
302 }
303 ENGINE_REF_PRINT(ret, 0, 1);
304 }
305 CRYPTO_THREAD_unlock(global_engine_lock);
306 /* Release the structural reference to the previous ENGINE */
307 ENGINE_free(e);
308 return ret;
309 }
310
ENGINE_get_prev(ENGINE * e)311 ENGINE *ENGINE_get_prev(ENGINE *e)
312 {
313 ENGINE *ret = NULL;
314 if (e == NULL) {
315 ERR_raise(ERR_LIB_ENGINE, ERR_R_PASSED_NULL_PARAMETER);
316 return NULL;
317 }
318 if (!CRYPTO_THREAD_write_lock(global_engine_lock))
319 return NULL;
320 ret = e->prev;
321 if (ret) {
322 int ref;
323
324 /* Return a valid structural reference to the next ENGINE */
325 if (!CRYPTO_UP_REF(&ret->struct_ref, &ref)) {
326 CRYPTO_THREAD_unlock(global_engine_lock);
327 ERR_raise(ERR_LIB_ENGINE, ERR_R_CRYPTO_LIB);
328 return NULL;
329 }
330 ENGINE_REF_PRINT(ret, 0, 1);
331 }
332 CRYPTO_THREAD_unlock(global_engine_lock);
333 /* Release the structural reference to the previous ENGINE */
334 ENGINE_free(e);
335 return ret;
336 }
337
338 /* Add another "ENGINE" type into the list. */
ENGINE_add(ENGINE * e)339 int ENGINE_add(ENGINE *e)
340 {
341 int to_return = 1;
342 if (e == NULL) {
343 ERR_raise(ERR_LIB_ENGINE, ERR_R_PASSED_NULL_PARAMETER);
344 return 0;
345 }
346 if ((e->id == NULL) || (e->name == NULL)) {
347 ERR_raise(ERR_LIB_ENGINE, ENGINE_R_ID_OR_NAME_MISSING);
348 return 0;
349 }
350 if (!CRYPTO_THREAD_write_lock(global_engine_lock))
351 return 0;
352 if (!engine_list_add(e)) {
353 ERR_raise(ERR_LIB_ENGINE, ENGINE_R_INTERNAL_LIST_ERROR);
354 to_return = 0;
355 }
356 CRYPTO_THREAD_unlock(global_engine_lock);
357 return to_return;
358 }
359
360 /* Remove an existing "ENGINE" type from the array. */
ENGINE_remove(ENGINE * e)361 int ENGINE_remove(ENGINE *e)
362 {
363 int to_return = 1;
364 if (e == NULL) {
365 ERR_raise(ERR_LIB_ENGINE, ERR_R_PASSED_NULL_PARAMETER);
366 return 0;
367 }
368 if (!CRYPTO_THREAD_write_lock(global_engine_lock))
369 return 0;
370 if (!engine_list_remove(e)) {
371 ERR_raise(ERR_LIB_ENGINE, ENGINE_R_INTERNAL_LIST_ERROR);
372 to_return = 0;
373 }
374 CRYPTO_THREAD_unlock(global_engine_lock);
375 return to_return;
376 }
377
engine_cpy(ENGINE * dest,const ENGINE * src)378 static void engine_cpy(ENGINE *dest, const ENGINE *src)
379 {
380 dest->id = src->id;
381 dest->name = src->name;
382 dest->rsa_meth = src->rsa_meth;
383 #ifndef OPENSSL_NO_DSA
384 dest->dsa_meth = src->dsa_meth;
385 #endif
386 #ifndef OPENSSL_NO_DH
387 dest->dh_meth = src->dh_meth;
388 #endif
389 #ifndef OPENSSL_NO_EC
390 dest->ec_meth = src->ec_meth;
391 #endif
392 dest->rand_meth = src->rand_meth;
393 dest->ciphers = src->ciphers;
394 dest->digests = src->digests;
395 dest->pkey_meths = src->pkey_meths;
396 dest->destroy = src->destroy;
397 dest->init = src->init;
398 dest->finish = src->finish;
399 dest->ctrl = src->ctrl;
400 dest->load_privkey = src->load_privkey;
401 dest->load_pubkey = src->load_pubkey;
402 dest->cmd_defns = src->cmd_defns;
403 dest->flags = src->flags;
404 dest->dynamic_id = src->dynamic_id;
405 engine_add_dynamic_id(dest, NULL, 0);
406 }
407
ENGINE_by_id(const char * id)408 ENGINE *ENGINE_by_id(const char *id)
409 {
410 ENGINE *iterator;
411 char *load_dir = NULL;
412 if (id == NULL) {
413 ERR_raise(ERR_LIB_ENGINE, ERR_R_PASSED_NULL_PARAMETER);
414 return NULL;
415 }
416 ENGINE_load_builtin_engines();
417
418 if (!RUN_ONCE(&engine_lock_init, do_engine_lock_init)) {
419 /* Maybe this should be raised in do_engine_lock_init() */
420 ERR_raise(ERR_LIB_ENGINE, ERR_R_CRYPTO_LIB);
421 return NULL;
422 }
423
424 if (!CRYPTO_THREAD_write_lock(global_engine_lock))
425 return NULL;
426 iterator = engine_list_head;
427 while (iterator && (strcmp(id, iterator->id) != 0))
428 iterator = iterator->next;
429 if (iterator != NULL) {
430 /*
431 * We need to return a structural reference. If this is an ENGINE
432 * type that returns copies, make a duplicate - otherwise increment
433 * the existing ENGINE's reference count.
434 */
435 if (iterator->flags & ENGINE_FLAGS_BY_ID_COPY) {
436 ENGINE *cp = ENGINE_new();
437 if (cp == NULL)
438 iterator = NULL;
439 else {
440 engine_cpy(cp, iterator);
441 iterator = cp;
442 }
443 } else {
444 int ref;
445
446 if (!CRYPTO_UP_REF(&iterator->struct_ref, &ref)) {
447 CRYPTO_THREAD_unlock(global_engine_lock);
448 ERR_raise(ERR_LIB_ENGINE, ERR_R_CRYPTO_LIB);
449 return NULL;
450 }
451 ENGINE_REF_PRINT(iterator, 0, 1);
452 }
453 }
454 CRYPTO_THREAD_unlock(global_engine_lock);
455 if (iterator != NULL)
456 return iterator;
457 /*
458 * Prevent infinite recursion if we're looking for the dynamic engine.
459 */
460 if (strcmp(id, "dynamic")) {
461 if ((load_dir = ossl_safe_getenv("OPENSSL_ENGINES")) == NULL)
462 load_dir = ENGINESDIR;
463 iterator = ENGINE_by_id("dynamic");
464 if (!iterator || !ENGINE_ctrl_cmd_string(iterator, "ID", id, 0) ||
465 !ENGINE_ctrl_cmd_string(iterator, "DIR_LOAD", "2", 0) ||
466 !ENGINE_ctrl_cmd_string(iterator, "DIR_ADD",
467 load_dir, 0) ||
468 !ENGINE_ctrl_cmd_string(iterator, "LIST_ADD", "1", 0) ||
469 !ENGINE_ctrl_cmd_string(iterator, "LOAD", NULL, 0))
470 goto notfound;
471 return iterator;
472 }
473 notfound:
474 ENGINE_free(iterator);
475 ERR_raise_data(ERR_LIB_ENGINE, ENGINE_R_NO_SUCH_ENGINE, "id=%s", id);
476 return NULL;
477 /* EEK! Experimental code ends */
478 }
479
ENGINE_up_ref(ENGINE * e)480 int ENGINE_up_ref(ENGINE *e)
481 {
482 int i;
483 if (e == NULL) {
484 ERR_raise(ERR_LIB_ENGINE, ERR_R_PASSED_NULL_PARAMETER);
485 return 0;
486 }
487 CRYPTO_UP_REF(&e->struct_ref, &i);
488 return 1;
489 }
490
