1 | /* |
2 | * Copyright 2001-2018 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 | #include "eng_local.h" |
12 | |
13 | /* |
14 | * The linked-list of pointers to engine types. engine_list_head incorporates |
15 | * an implicit structural reference but engine_list_tail does not - the |
16 | * latter is a computational optimization and only points to something that |
17 | * is already pointed to by its predecessor in the list (or engine_list_head |
18 | * itself). In the same way, the use of the "prev" pointer in each ENGINE is |
19 | * to save excessive list iteration, it doesn't correspond to an extra |
20 | * structural reference. Hence, engine_list_head, and each non-null "next" |
21 | * pointer account for the list itself assuming exactly 1 structural |
22 | * reference on each list member. |
23 | */ |
24 | static ENGINE *engine_list_head = NULL; |
25 | static ENGINE *engine_list_tail = NULL; |
26 | |
27 | /* |
28 | * This cleanup function is only needed internally. If it should be called, |
29 | * we register it with the "engine_cleanup_int()" stack to be called during |
30 | * cleanup. |
31 | */ |
32 | |
33 | static void engine_list_cleanup(void) |
34 | { |
35 | ENGINE *iterator = engine_list_head; |
36 | |
37 | while (iterator != NULL) { |
38 | ENGINE_remove(iterator); |
39 | iterator = engine_list_head; |
40 | } |
41 | return; |
42 | } |
43 | |
44 | /* |
45 | * These static functions starting with a lower case "engine_" always take |
46 | * place when global_engine_lock has been locked up. |
47 | */ |
48 | static int engine_list_add(ENGINE *e) |
49 | { |
50 | int conflict = 0; |
51 | ENGINE *iterator = NULL; |
52 | |
53 | if (e == NULL) { |
54 | ENGINEerr(ENGINE_F_ENGINE_LIST_ADD, ERR_R_PASSED_NULL_PARAMETER); |
55 | return 0; |
56 | } |
57 | iterator = engine_list_head; |
58 | while (iterator && !conflict) { |
59 | conflict = (strcmp(iterator->id, e->id) == 0); |
60 | iterator = iterator->next; |
61 | } |
62 | if (conflict) { |
63 | ENGINEerr(ENGINE_F_ENGINE_LIST_ADD, ENGINE_R_CONFLICTING_ENGINE_ID); |
64 | return 0; |
65 | } |
66 | if (engine_list_head == NULL) { |
67 | /* We are adding to an empty list. */ |
68 | if (engine_list_tail) { |
69 | ENGINEerr(ENGINE_F_ENGINE_LIST_ADD, ENGINE_R_INTERNAL_LIST_ERROR); |
70 | return 0; |
71 | } |
72 | engine_list_head = e; |
73 | e->prev = NULL; |
74 | /* |
75 | * The first time the list allocates, we should register the cleanup. |
76 | */ |
77 | engine_cleanup_add_last(engine_list_cleanup); |
78 | } else { |
79 | /* We are adding to the tail of an existing list. */ |
80 | if ((engine_list_tail == NULL) || (engine_list_tail->next != NULL)) { |
81 | ENGINEerr(ENGINE_F_ENGINE_LIST_ADD, ENGINE_R_INTERNAL_LIST_ERROR); |
82 | return 0; |
83 | } |
84 | engine_list_tail->next = e; |
85 | e->prev = engine_list_tail; |
86 | } |
87 | /* |
88 | * Having the engine in the list assumes a structural reference. |
89 | */ |
90 | e->struct_ref++; |
91 | engine_ref_debug(e, 0, 1); |
92 | /* However it came to be, e is the last item in the list. */ |
93 | engine_list_tail = e; |
94 | e->next = NULL; |
95 | return 1; |
96 | } |
97 | |
98 | static int engine_list_remove(ENGINE *e) |
99 | { |
100 | ENGINE *iterator; |
101 | |
102 | if (e == NULL) { |
103 | ENGINEerr(ENGINE_F_ENGINE_LIST_REMOVE, ERR_R_PASSED_NULL_PARAMETER); |
104 | return 0; |
105 | } |
106 | /* We need to check that e is in our linked list! */ |
107 | iterator = engine_list_head; |
108 | while (iterator && (iterator != e)) |
109 | iterator = iterator->next; |
110 | if (iterator == NULL) { |
111 | ENGINEerr(ENGINE_F_ENGINE_LIST_REMOVE, |
112 | ENGINE_R_ENGINE_IS_NOT_IN_LIST); |
113 | return 0; |
114 | } |
115 | /* un-link e from the chain. */ |
116 | if (e->next) |
117 | e->next->prev = e->prev; |
118 | if (e->prev) |
119 | e->prev->next = e->next; |
120 | /* Correct our head/tail if necessary. */ |
121 | if (engine_list_head == e) |
122 | engine_list_head = e->next; |
123 | if (engine_list_tail == e) |
124 | engine_list_tail = e->prev; |
125 | engine_free_util(e, 0); |
126 | return 1; |
127 | } |
128 | |
129 | /* Get the first/last "ENGINE" type available. */ |
130 | ENGINE *ENGINE_get_first(void) |
131 | { |
132 | ENGINE *ret; |
133 | |
134 | if (!RUN_ONCE(&engine_lock_init, do_engine_lock_init)) { |
135 | ENGINEerr(ENGINE_F_ENGINE_GET_FIRST, ERR_R_MALLOC_FAILURE); |
136 | return NULL; |
137 | } |
138 | |
139 | CRYPTO_THREAD_write_lock(global_engine_lock); |
140 | ret = engine_list_head; |
141 | if (ret) { |
142 | ret->struct_ref++; |
143 | engine_ref_debug(ret, 0, 1); |
144 | } |
145 | CRYPTO_THREAD_unlock(global_engine_lock); |
146 | return ret; |
147 | } |
148 | |
149 | ENGINE *ENGINE_get_last(void) |
150 | { |
151 | ENGINE *ret; |
152 | |
153 | if (!RUN_ONCE(&engine_lock_init, do_engine_lock_init)) { |
154 | ENGINEerr(ENGINE_F_ENGINE_GET_LAST, ERR_R_MALLOC_FAILURE); |
155 | return NULL; |
156 | } |
157 | |
158 | CRYPTO_THREAD_write_lock(global_engine_lock); |
159 | ret = engine_list_tail; |
160 | if (ret) { |
161 | ret->struct_ref++; |
162 | engine_ref_debug(ret, 0, 1); |
163 | } |
164 | CRYPTO_THREAD_unlock(global_engine_lock); |
165 | return ret; |
166 | } |
167 | |
168 | /* Iterate to the next/previous "ENGINE" type (NULL = end of the list). */ |
169 | ENGINE *ENGINE_get_next(ENGINE *e) |
170 | { |
171 | ENGINE *ret = NULL; |
172 | if (e == NULL) { |
173 | ENGINEerr(ENGINE_F_ENGINE_GET_NEXT, ERR_R_PASSED_NULL_PARAMETER); |
174 | return 0; |
175 | } |
176 | CRYPTO_THREAD_write_lock(global_engine_lock); |
177 | ret = e->next; |
178 | if (ret) { |
179 | /* Return a valid structural reference to the next ENGINE */ |
180 | ret->struct_ref++; |
181 | engine_ref_debug(ret, 0, 1); |
182 | } |
183 | CRYPTO_THREAD_unlock(global_engine_lock); |
184 | /* Release the structural reference to the previous ENGINE */ |
185 | ENGINE_free(e); |
186 | return ret; |
187 | } |
188 | |
189 | ENGINE *ENGINE_get_prev(ENGINE *e) |
190 | { |
191 | ENGINE *ret = NULL; |
192 | if (e == NULL) { |
193 | ENGINEerr(ENGINE_F_ENGINE_GET_PREV, ERR_R_PASSED_NULL_PARAMETER); |
194 | return 0; |
195 | } |
196 | CRYPTO_THREAD_write_lock(global_engine_lock); |
197 | ret = e->prev; |
198 | if (ret) { |
199 | /* Return a valid structural reference to the next ENGINE */ |
200 | ret->struct_ref++; |
201 | engine_ref_debug(ret, 0, 1); |
202 | } |
203 | CRYPTO_THREAD_unlock(global_engine_lock); |
204 | /* Release the structural reference to the previous ENGINE */ |
205 | ENGINE_free(e); |
206 | return ret; |
207 | } |
208 | |
209 | /* Add another "ENGINE" type into the list. */ |
210 | int ENGINE_add(ENGINE *e) |
211 | { |
212 | int to_return = 1; |
213 | if (e == NULL) { |
214 | ENGINEerr(ENGINE_F_ENGINE_ADD, ERR_R_PASSED_NULL_PARAMETER); |
215 | return 0; |
216 | } |
217 | if ((e->id == NULL) || (e->name == NULL)) { |
218 | ENGINEerr(ENGINE_F_ENGINE_ADD, ENGINE_R_ID_OR_NAME_MISSING); |
219 | return 0; |
220 | } |
221 | CRYPTO_THREAD_write_lock(global_engine_lock); |
222 | if (!engine_list_add(e)) { |
223 | ENGINEerr(ENGINE_F_ENGINE_ADD, ENGINE_R_INTERNAL_LIST_ERROR); |
224 | to_return = 0; |
225 | } |
226 | CRYPTO_THREAD_unlock(global_engine_lock); |
227 | return to_return; |
228 | } |
229 | |
230 | /* Remove an existing "ENGINE" type from the array. */ |
231 | int ENGINE_remove(ENGINE *e) |
232 | { |
233 | int to_return = 1; |
234 | if (e == NULL) { |
235 | ENGINEerr(ENGINE_F_ENGINE_REMOVE, ERR_R_PASSED_NULL_PARAMETER); |
236 | return 0; |
237 | } |
238 | CRYPTO_THREAD_write_lock(global_engine_lock); |
239 | if (!engine_list_remove(e)) { |
240 | ENGINEerr(ENGINE_F_ENGINE_REMOVE, ENGINE_R_INTERNAL_LIST_ERROR); |
241 | to_return = 0; |
242 | } |
243 | CRYPTO_THREAD_unlock(global_engine_lock); |
244 | return to_return; |
245 | } |
246 | |
247 | static void engine_cpy(ENGINE *dest, const ENGINE *src) |
248 | { |
249 | dest->id = src->id; |
250 | dest->name = src->name; |
251 | #ifndef OPENSSL_NO_RSA |
252 | dest->rsa_meth = src->rsa_meth; |
253 | #endif |
254 | #ifndef OPENSSL_NO_DSA |
255 | dest->dsa_meth = src->dsa_meth; |
256 | #endif |
257 | #ifndef OPENSSL_NO_DH |
258 | dest->dh_meth = src->dh_meth; |
259 | #endif |
260 | #ifndef OPENSSL_NO_EC |
261 | dest->ec_meth = src->ec_meth; |
262 | #endif |
263 | dest->rand_meth = src->rand_meth; |
264 | dest->ciphers = src->ciphers; |
265 | dest->digests = src->digests; |
266 | dest->pkey_meths = src->pkey_meths; |
267 | dest->destroy = src->destroy; |
268 | dest->init = src->init; |
269 | dest->finish = src->finish; |
270 | dest->ctrl = src->ctrl; |
271 | dest->load_privkey = src->load_privkey; |
272 | dest->load_pubkey = src->load_pubkey; |
273 | dest->cmd_defns = src->cmd_defns; |
274 | dest->flags = src->flags; |
275 | } |
276 | |
277 | ENGINE *ENGINE_by_id(const char *id) |
278 | { |
279 | ENGINE *iterator; |
280 | char *load_dir = NULL; |
281 | if (id == NULL) { |
282 | ENGINEerr(ENGINE_F_ENGINE_BY_ID, ERR_R_PASSED_NULL_PARAMETER); |
283 | return NULL; |
284 | } |
285 | if (!RUN_ONCE(&engine_lock_init, do_engine_lock_init)) { |
286 | ENGINEerr(ENGINE_F_ENGINE_BY_ID, ERR_R_MALLOC_FAILURE); |
287 | return NULL; |
288 | } |
289 | |
290 | CRYPTO_THREAD_write_lock(global_engine_lock); |
291 | iterator = engine_list_head; |
292 | while (iterator && (strcmp(id, iterator->id) != 0)) |
293 | iterator = iterator->next; |
294 | if (iterator != NULL) { |
295 | /* |
296 | * We need to return a structural reference. If this is an ENGINE |
297 | * type that returns copies, make a duplicate - otherwise increment |
298 | * the existing ENGINE's reference count. |
299 | */ |
300 | if (iterator->flags & ENGINE_FLAGS_BY_ID_COPY) { |
301 | ENGINE *cp = ENGINE_new(); |
302 | if (cp == NULL) |
303 | iterator = NULL; |
304 | else { |
305 | engine_cpy(cp, iterator); |
306 | iterator = cp; |
307 | } |
308 | } else { |
309 | iterator->struct_ref++; |
310 | engine_ref_debug(iterator, 0, 1); |
311 | } |
312 | } |
313 | CRYPTO_THREAD_unlock(global_engine_lock); |
314 | if (iterator != NULL) |
315 | return iterator; |
316 | /* |
317 | * Prevent infinite recursion if we're looking for the dynamic engine. |
318 | */ |
319 | if (strcmp(id, "dynamic" )) { |
320 | if ((load_dir = ossl_safe_getenv("OPENSSL_ENGINES" )) == NULL) |
321 | load_dir = ENGINESDIR; |
322 | iterator = ENGINE_by_id("dynamic" ); |
323 | if (!iterator || !ENGINE_ctrl_cmd_string(iterator, "ID" , id, 0) || |
324 | !ENGINE_ctrl_cmd_string(iterator, "DIR_LOAD" , "2" , 0) || |
325 | !ENGINE_ctrl_cmd_string(iterator, "DIR_ADD" , |
326 | load_dir, 0) || |
327 | !ENGINE_ctrl_cmd_string(iterator, "LIST_ADD" , "1" , 0) || |
328 | !ENGINE_ctrl_cmd_string(iterator, "LOAD" , NULL, 0)) |
329 | goto notfound; |
330 | return iterator; |
331 | } |
332 | notfound: |
333 | ENGINE_free(iterator); |
334 | ENGINEerr(ENGINE_F_ENGINE_BY_ID, ENGINE_R_NO_SUCH_ENGINE); |
335 | ERR_add_error_data(2, "id=" , id); |
336 | return NULL; |
337 | /* EEK! Experimental code ends */ |
338 | } |
339 | |
340 | int ENGINE_up_ref(ENGINE *e) |
341 | { |
342 | int i; |
343 | if (e == NULL) { |
344 | ENGINEerr(ENGINE_F_ENGINE_UP_REF, ERR_R_PASSED_NULL_PARAMETER); |
345 | return 0; |
346 | } |
347 | CRYPTO_UP_REF(&e->struct_ref, &i, global_engine_lock); |
348 | return 1; |
349 | } |
350 | |