2 * Copyright 2001-2023 The OpenSSL Project Authors. All Rights Reserved.
4 * Licensed under the Apache License 2.0 (the "License"). You may not use
5 * this file except in compliance with the License. You can obtain a copy
6 * in the file LICENSE in the source distribution or at
7 * https://www.openssl.org/source/license.html
10 #include "internal/cryptlib.h"
11 #include <openssl/evp.h>
12 #include <openssl/lhash.h>
13 #include <openssl/trace.h>
14 #include "eng_local.h"
16 /* The type of the items in the table */
17 struct st_engine_pile {
18 /* The 'nid' of this algorithm/mode */
20 /* ENGINEs that implement this algorithm/mode. */
22 /* The default ENGINE to perform this algorithm/mode. */
25 * Zero if 'sk' is newer than the cached 'funct', non-zero otherwise
30 /* The type exposed in eng_local.h */
31 struct st_engine_table {
32 LHASH_OF(ENGINE_PILE) piles;
35 typedef struct st_engine_pile_doall {
36 engine_table_doall_cb *cb;
40 /* Global flags (ENGINE_TABLE_FLAG_***). */
41 static unsigned int table_flags = 0;
43 /* API function manipulating 'table_flags' */
44 unsigned int ENGINE_get_table_flags(void)
49 void ENGINE_set_table_flags(unsigned int flags)
54 /* Internal functions for the "piles" hash table */
55 static unsigned long engine_pile_hash(const ENGINE_PILE *c)
60 static int engine_pile_cmp(const ENGINE_PILE *a, const ENGINE_PILE *b)
62 return a->nid - b->nid;
65 static int int_table_check(ENGINE_TABLE **t, int create)
67 LHASH_OF(ENGINE_PILE) *lh;
73 if ((lh = lh_ENGINE_PILE_new(engine_pile_hash, engine_pile_cmp)) == NULL)
75 *t = (ENGINE_TABLE *)lh;
80 * Privately exposed (via eng_local.h) functions for adding and/or removing
81 * ENGINEs from the implementation table
83 int engine_table_register(ENGINE_TABLE **table, ENGINE_CLEANUP_CB *cleanup,
84 ENGINE *e, const int *nids, int num_nids,
87 int ret = 0, added = 0;
88 ENGINE_PILE tmplate, *fnd;
90 if (!CRYPTO_THREAD_write_lock(global_engine_lock))
94 if (!int_table_check(table, 1))
96 /* The cleanup callback needs to be added */
97 if (added && !engine_cleanup_add_first(cleanup)) {
98 lh_ENGINE_PILE_free(&(*table)->piles);
104 fnd = lh_ENGINE_PILE_retrieve(&(*table)->piles, &tmplate);
106 fnd = OPENSSL_malloc(sizeof(*fnd));
111 fnd->sk = sk_ENGINE_new_null();
117 (void)lh_ENGINE_PILE_insert(&(*table)->piles, fnd);
118 if (lh_ENGINE_PILE_retrieve(&(*table)->piles, &tmplate) != fnd) {
119 sk_ENGINE_free(fnd->sk);
124 /* A registration shouldn't add duplicate entries */
125 (void)sk_ENGINE_delete_ptr(fnd->sk, e);
127 * if 'setdefault', this ENGINE goes to the head of the list
129 if (!sk_ENGINE_push(fnd->sk, e))
131 /* "touch" this ENGINE_PILE */
134 if (!engine_unlocked_init(e)) {
135 ERR_raise(ERR_LIB_ENGINE, ENGINE_R_INIT_FAILED);
139 engine_unlocked_finish(fnd->funct, 0);
147 CRYPTO_THREAD_unlock(global_engine_lock);
151 static void int_unregister_cb(ENGINE_PILE *pile, ENGINE *e)
154 /* Iterate the 'c->sk' stack removing any occurrence of 'e' */
155 while ((n = sk_ENGINE_find(pile->sk, e)) >= 0) {
156 (void)sk_ENGINE_delete(pile->sk, n);
159 if (pile->funct == e) {
160 engine_unlocked_finish(e, 0);
165 IMPLEMENT_LHASH_DOALL_ARG(ENGINE_PILE, ENGINE);
167 void engine_table_unregister(ENGINE_TABLE **table, ENGINE *e)
169 if (!CRYPTO_THREAD_write_lock(global_engine_lock))
170 /* Can't return a value. :( */
172 if (int_table_check(table, 0))
173 lh_ENGINE_PILE_doall_ENGINE(&(*table)->piles, int_unregister_cb, e);
174 CRYPTO_THREAD_unlock(global_engine_lock);
177 static void int_cleanup_cb_doall(ENGINE_PILE *p)
181 sk_ENGINE_free(p->sk);
183 engine_unlocked_finish(p->funct, 0);
187 void engine_table_cleanup(ENGINE_TABLE **table)
189 if (!CRYPTO_THREAD_write_lock(global_engine_lock))
192 lh_ENGINE_PILE_doall(&(*table)->piles, int_cleanup_cb_doall);
193 lh_ENGINE_PILE_free(&(*table)->piles);
196 CRYPTO_THREAD_unlock(global_engine_lock);
199 /* return a functional reference for a given 'nid' */
200 ENGINE *ossl_engine_table_select(ENGINE_TABLE **table, int nid,
201 const char *f, int l)
204 ENGINE_PILE tmplate, *fnd = NULL;
205 int initres, loop = 0;
207 #ifndef OPENSSL_NO_AUTOLOAD_CONFIG
208 /* Load the config before trying to check if engines are available */
209 OPENSSL_init_crypto(OPENSSL_INIT_LOAD_CONFIG, NULL);
213 OSSL_TRACE3(ENGINE_TABLE,
214 "%s:%d, nid=%d, nothing registered!\n",
219 if (!CRYPTO_THREAD_write_lock(global_engine_lock))
222 * Check again inside the lock otherwise we could race against cleanup
223 * operations. But don't worry about a debug printout
225 if (!int_table_check(table, 0))
228 fnd = lh_ENGINE_PILE_retrieve(&(*table)->piles, &tmplate);
231 if (fnd->funct && engine_unlocked_init(fnd->funct)) {
232 OSSL_TRACE4(ENGINE_TABLE,
233 "%s:%d, nid=%d, using ENGINE '%s' cached\n",
234 f, l, nid, fnd->funct->id);
243 ret = sk_ENGINE_value(fnd->sk, loop++);
245 OSSL_TRACE3(ENGINE_TABLE,
247 "no registered implementations would initialise\n",
251 /* Try to initialise the ENGINE? */
252 if ((ret->funct_ref > 0) || !(table_flags & ENGINE_TABLE_FLAG_NOINIT))
253 initres = engine_unlocked_init(ret);
258 if ((fnd->funct != ret) && engine_unlocked_init(ret)) {
259 /* If there was a previous default we release it. */
261 engine_unlocked_finish(fnd->funct, 0);
263 OSSL_TRACE4(ENGINE_TABLE,
264 "%s:%d, nid=%d, setting default to '%s'\n",
267 OSSL_TRACE4(ENGINE_TABLE,
268 "%s:%d, nid=%d, using newly initialised '%s'\n",
275 * If it failed, it is unlikely to succeed again until some future
276 * registrations have taken place. In all cases, we cache.
281 OSSL_TRACE4(ENGINE_TABLE,
282 "%s:%d, nid=%d, caching ENGINE '%s'\n",
285 OSSL_TRACE3(ENGINE_TABLE,
286 "%s:%d, nid=%d, caching 'no matching ENGINE'\n",
288 CRYPTO_THREAD_unlock(global_engine_lock);
290 * Whatever happened, any failed init()s are not failures in this
291 * context, so clear our error state.
297 /* Table enumeration */
299 static void int_dall(const ENGINE_PILE *pile, ENGINE_PILE_DOALL *dall)
301 dall->cb(pile->nid, pile->sk, pile->funct, dall->arg);
304 IMPLEMENT_LHASH_DOALL_ARG_CONST(ENGINE_PILE, ENGINE_PILE_DOALL);
306 void engine_table_doall(ENGINE_TABLE *table, engine_table_doall_cb *cb,
309 ENGINE_PILE_DOALL dall;
313 lh_ENGINE_PILE_doall_ENGINE_PILE_DOALL(&table->piles, int_dall, &dall);