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
62 if (e == NULL) {
63 ERR_raise(ERR_LIB_ENGINE, ERR_R_PASSED_NULL_PARAMETER);
64 return 0;
65 }
66 iterator = engine_list_head;
67 while (iterator && !conflict) {
68 conflict = (strcmp(iterator->id, e->id) == 0);
69 iterator = iterator->next;
70 }
71 if (conflict) {
72 ERR_raise(ERR_LIB_ENGINE, ENGINE_R_CONFLICTING_ENGINE_ID);
73 return 0;
74 }
75 if (engine_list_head == NULL) {
76 /* We are adding to an empty list. */
77 if (engine_list_tail) {
78 ERR_raise(ERR_LIB_ENGINE, ENGINE_R_INTERNAL_LIST_ERROR);
79 return 0;
80 }
81 /*
82 * The first time the list allocates, we should register the cleanup.
83 */
84 if (!engine_cleanup_add_last(engine_list_cleanup)) {
85 ERR_raise(ERR_LIB_ENGINE, ENGINE_R_INTERNAL_LIST_ERROR);
86 return 0;
87 }
88 engine_list_head = e;
89 e->prev = NULL;
90 } else {
91 /* We are adding to the tail of an existing list. */
92 if ((engine_list_tail == NULL) || (engine_list_tail->next != NULL)) {
93 ERR_raise(ERR_LIB_ENGINE, ENGINE_R_INTERNAL_LIST_ERROR);
94 return 0;
95 }
96 engine_list_tail->next = e;
97 e->prev = engine_list_tail;
98 }
99 /*
100 * Having the engine in the list assumes a structural reference.
101 */
102 e->struct_ref++;
103 ENGINE_REF_PRINT(e, 0, 1);
104 /* However it came to be, e is the last item in the list. */
105 engine_list_tail = e;
106 e->next = NULL;
107 return 1;
108 }
109
engine_list_remove(ENGINE * e)110 static int engine_list_remove(ENGINE *e)
111 {
112 ENGINE *iterator;
113
114 if (e == NULL) {
115 ERR_raise(ERR_LIB_ENGINE, ERR_R_PASSED_NULL_PARAMETER);
116 return 0;
117 }
118 /* We need to check that e is in our linked list! */
119 iterator = engine_list_head;
120 while (iterator && (iterator != e))
121 iterator = iterator->next;
122 if (iterator == NULL) {
123 ERR_raise(ERR_LIB_ENGINE, ENGINE_R_ENGINE_IS_NOT_IN_LIST);
124 return 0;
125 }
126 /* un-link e from the chain. */
127 if (e->next)
128 e->next->prev = e->prev;
129 if (e->prev)
130 e->prev->next = e->next;
131 /* Correct our head/tail if necessary. */
132 if (engine_list_head == e)
133 engine_list_head = e->next;
134 if (engine_list_tail == e)
135 engine_list_tail = e->prev;
136 engine_free_util(e, 0);
137 return 1;
138 }
139
140 /* Add engine to dynamic engine list. */
engine_add_dynamic_id(ENGINE * e,ENGINE_DYNAMIC_ID dynamic_id,int not_locked)141 int engine_add_dynamic_id(ENGINE *e, ENGINE_DYNAMIC_ID dynamic_id,
142 int not_locked)
143 {
144 int result = 0;
145 ENGINE *iterator = NULL;
146
147 if (e == NULL)
148 return 0;
149
150 if (e->dynamic_id == NULL && dynamic_id == NULL)
151 return 0;
152
153 if (not_locked && !CRYPTO_THREAD_write_lock(global_engine_lock))
154 return 0;
155
156 if (dynamic_id != NULL) {
157 iterator = engine_dyn_list_head;
158 while (iterator != NULL) {
159 if (iterator->dynamic_id == dynamic_id)
160 goto err;
161 iterator = iterator->next;
162 }
163 if (e->dynamic_id != NULL)
164 goto err;
165 e->dynamic_id = dynamic_id;
166 }
167
168 if (engine_dyn_list_head == NULL) {
169 /* We are adding to an empty list. */
170 if (engine_dyn_list_tail != NULL)
171 goto err;
172 engine_dyn_list_head = e;
173 e->prev_dyn = NULL;
174 } else {
175 /* We are adding to the tail of an existing list. */
176 if (engine_dyn_list_tail == NULL
177 || engine_dyn_list_tail->next_dyn != NULL)
178 goto err;
179 engine_dyn_list_tail->next_dyn = e;
180 e->prev_dyn = engine_dyn_list_tail;
181 }
182
183 engine_dyn_list_tail = e;
184 e->next_dyn = NULL;
185 result = 1;
186
187 err:
188 if (not_locked)
189 CRYPTO_THREAD_unlock(global_engine_lock);
190 return result;
191 }
192
193 /* Remove engine from dynamic engine list. */
engine_remove_dynamic_id(ENGINE * e,int not_locked)194 void engine_remove_dynamic_id(ENGINE *e, int not_locked)
195 {
196 if (e == NULL || e->dynamic_id == NULL)
197 return;
198
199 if (not_locked && !CRYPTO_THREAD_write_lock(global_engine_lock))
200 return;
201
202 e->dynamic_id = NULL;
203
204 /* un-link e from the chain. */
205 if (e->next_dyn != NULL)
206 e->next_dyn->prev_dyn = e->prev_dyn;
207 if (e->prev_dyn != NULL)
208 e->prev_dyn->next_dyn = e->next_dyn;
209 /* Correct our head/tail if necessary. */
210 if (engine_dyn_list_head == e)
211 engine_dyn_list_head = e->next_dyn;
212 if (engine_dyn_list_tail == e)
213 engine_dyn_list_tail = e->prev_dyn;
214
215 if (not_locked)
216 CRYPTO_THREAD_unlock(global_engine_lock);
217 }
218
219 /* Get the first/last "ENGINE" type available. */
ENGINE_get_first(void)220 ENGINE *ENGINE_get_first(void)
221 {
222 ENGINE *ret;
223
224 if (!RUN_ONCE(&engine_lock_init, do_engine_lock_init)) {
225 ERR_raise(ERR_LIB_ENGINE, ERR_R_MALLOC_FAILURE);
226 return NULL;
227 }
228
229 if (!CRYPTO_THREAD_write_lock(global_engine_lock))
230 return NULL;
231 ret = engine_list_head;
232 if (ret) {
233 ret->struct_ref++;
234 ENGINE_REF_PRINT(ret, 0, 1);
235 }
236 CRYPTO_THREAD_unlock(global_engine_lock);
237 return ret;
238 }
239
ENGINE_get_last(void)240 ENGINE *ENGINE_get_last(void)
241 {
242 ENGINE *ret;
243
244 if (!RUN_ONCE(&engine_lock_init, do_engine_lock_init)) {
245 ERR_raise(ERR_LIB_ENGINE, ERR_R_MALLOC_FAILURE);
246 return NULL;
247 }
248
249 if (!CRYPTO_THREAD_write_lock(global_engine_lock))
250 return NULL;
251 ret = engine_list_tail;
252 if (ret) {
253 ret->struct_ref++;
254 ENGINE_REF_PRINT(ret, 0, 1);
255 }
256 CRYPTO_THREAD_unlock(global_engine_lock);
257 return ret;
258 }
259
260 /* Iterate to the next/previous "ENGINE" type (NULL = end of the list). */
ENGINE_get_next(ENGINE * e)261 ENGINE *ENGINE_get_next(ENGINE *e)
262 {
263 ENGINE *ret = NULL;
264 if (e == NULL) {
265 ERR_raise(ERR_LIB_ENGINE, ERR_R_PASSED_NULL_PARAMETER);
266 return NULL;
267 }
268 if (!CRYPTO_THREAD_write_lock(global_engine_lock))
269 return NULL;
270 ret = e->next;
271 if (ret) {
272 /* Return a valid structural reference to the next ENGINE */
273 ret->struct_ref++;
274 ENGINE_REF_PRINT(ret, 0, 1);
275 }
276 CRYPTO_THREAD_unlock(global_engine_lock);
277 /* Release the structural reference to the previous ENGINE */
278 ENGINE_free(e);
279 return ret;
280 }
281
ENGINE_get_prev(ENGINE * e)282 ENGINE *ENGINE_get_prev(ENGINE *e)
283 {
284 ENGINE *ret = NULL;
285 if (e == NULL) {
286 ERR_raise(ERR_LIB_ENGINE, ERR_R_PASSED_NULL_PARAMETER);
287 return NULL;
288 }
289 if (!CRYPTO_THREAD_write_lock(global_engine_lock))
290 return NULL;
291 ret = e->prev;
292 if (ret) {
293 /* Return a valid structural reference to the next ENGINE */
294 ret->struct_ref++;
295 ENGINE_REF_PRINT(ret, 0, 1);
296 }
297 CRYPTO_THREAD_unlock(global_engine_lock);
298 /* Release the structural reference to the previous ENGINE */
299 ENGINE_free(e);
300 return ret;
301 }
302
303 /* Add another "ENGINE" type into the list. */
ENGINE_add(ENGINE * e)304 int ENGINE_add(ENGINE *e)
305 {
306 int to_return = 1;
307 if (e == NULL) {
308 ERR_raise(ERR_LIB_ENGINE, ERR_R_PASSED_NULL_PARAMETER);
309 return 0;
310 }
311 if ((e->id == NULL) || (e->name == NULL)) {
312 ERR_raise(ERR_LIB_ENGINE, ENGINE_R_ID_OR_NAME_MISSING);
313 return 0;
314 }
315 if (!CRYPTO_THREAD_write_lock(global_engine_lock))
316 return 0;
317 if (!engine_list_add(e)) {
318 ERR_raise(ERR_LIB_ENGINE, ENGINE_R_INTERNAL_LIST_ERROR);
319 to_return = 0;
320 }
321 CRYPTO_THREAD_unlock(global_engine_lock);
322 return to_return;
323 }
324
325 /* Remove an existing "ENGINE" type from the array. */
ENGINE_remove(ENGINE * e)326 int ENGINE_remove(ENGINE *e)
327 {
328 int to_return = 1;
329 if (e == NULL) {
330 ERR_raise(ERR_LIB_ENGINE, ERR_R_PASSED_NULL_PARAMETER);
331 return 0;
332 }
333 if (!CRYPTO_THREAD_write_lock(global_engine_lock))
334 return 0;
335 if (!engine_list_remove(e)) {
336 ERR_raise(ERR_LIB_ENGINE, ENGINE_R_INTERNAL_LIST_ERROR);
337 to_return = 0;
338 }
339 CRYPTO_THREAD_unlock(global_engine_lock);
340 return to_return;
341 }
342
engine_cpy(ENGINE * dest,const ENGINE * src)343 static void engine_cpy(ENGINE *dest, const ENGINE *src)
344 {
345 dest->id = src->id;
346 dest->name = src->name;
347 dest->rsa_meth = src->rsa_meth;
348 #ifndef OPENSSL_NO_DSA
349 dest->dsa_meth = src->dsa_meth;
350 #endif
351 #ifndef OPENSSL_NO_DH
352 dest->dh_meth = src->dh_meth;
353 #endif
354 #ifndef OPENSSL_NO_EC
355 dest->ec_meth = src->ec_meth;
356 #endif
357 dest->rand_meth = src->rand_meth;
358 dest->ciphers = src->ciphers;
359 dest->digests = src->digests;
360 dest->pkey_meths = src->pkey_meths;
361 dest->destroy = src->destroy;
362 dest->init = src->init;
363 dest->finish = src->finish;
364 dest->ctrl = src->ctrl;
365 dest->load_privkey = src->load_privkey;
366 dest->load_pubkey = src->load_pubkey;
367 dest->cmd_defns = src->cmd_defns;
368 dest->flags = src->flags;
369 dest->dynamic_id = src->dynamic_id;
370 engine_add_dynamic_id(dest, NULL, 0);
371 }
372
ENGINE_by_id(const char * id)373 ENGINE *ENGINE_by_id(const char *id)
374 {
375 ENGINE *iterator;
376 char *load_dir = NULL;
377 if (id == NULL) {
378 ERR_raise(ERR_LIB_ENGINE, ERR_R_PASSED_NULL_PARAMETER);
379 return NULL;
380 }
381 ENGINE_load_builtin_engines();
382
383 if (!RUN_ONCE(&engine_lock_init, do_engine_lock_init)) {
384 ERR_raise(ERR_LIB_ENGINE, ERR_R_MALLOC_FAILURE);
385 return NULL;
386 }
387
388 if (!CRYPTO_THREAD_write_lock(global_engine_lock))
389 return NULL;
390 iterator = engine_list_head;
391 while (iterator && (strcmp(id, iterator->id) != 0))
392 iterator = iterator->next;
393 if (iterator != NULL) {
394 /*
395 * We need to return a structural reference. If this is an ENGINE
396 * type that returns copies, make a duplicate - otherwise increment
397 * the existing ENGINE's reference count.
398 */
399 if (iterator->flags & ENGINE_FLAGS_BY_ID_COPY) {
400 ENGINE *cp = ENGINE_new();
401 if (cp == NULL)
402 iterator = NULL;
403 else {
404 engine_cpy(cp, iterator);
405 iterator = cp;
406 }
407 } else {
408 iterator->struct_ref++;
409 ENGINE_REF_PRINT(iterator, 0, 1);
410 }
411 }
412 CRYPTO_THREAD_unlock(global_engine_lock);
413 if (iterator != NULL)
414 return iterator;
415 /*
416 * Prevent infinite recursion if we're looking for the dynamic engine.
417 */
418 if (strcmp(id, "dynamic")) {
419 if ((load_dir = ossl_safe_getenv("OPENSSL_ENGINES")) == NULL)
420 load_dir = ENGINESDIR;
421 iterator = ENGINE_by_id("dynamic");
422 if (!iterator || !ENGINE_ctrl_cmd_string(iterator, "ID", id, 0) ||
423 !ENGINE_ctrl_cmd_string(iterator, "DIR_LOAD", "2", 0) ||
424 !ENGINE_ctrl_cmd_string(iterator, "DIR_ADD",
425 load_dir, 0) ||
426 !ENGINE_ctrl_cmd_string(iterator, "LIST_ADD", "1", 0) ||
427 !ENGINE_ctrl_cmd_string(iterator, "LOAD", NULL, 0))
428 goto notfound;
429 return iterator;
430 }
431 notfound:
432 ENGINE_free(iterator);
433 ERR_raise_data(ERR_LIB_ENGINE, ENGINE_R_NO_SUCH_ENGINE, "id=%s", id);
434 return NULL;
435 /* EEK! Experimental code ends */
436 }
437
ENGINE_up_ref(ENGINE * e)438 int ENGINE_up_ref(ENGINE *e)
439 {
440 int i;
441 if (e == NULL) {
442 ERR_raise(ERR_LIB_ENGINE, ERR_R_PASSED_NULL_PARAMETER);
443 return 0;
444 }
445 CRYPTO_UP_REF(&e->struct_ref, &i, global_engine_lock);
446 return 1;
447 }
448