2 * Copyright 2019-2021 The OpenSSL Project Authors. All Rights Reserved.
3 * Copyright (c) 2019, Oracle and/or its affiliates. All rights reserved.
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
14 #include <openssl/crypto.h>
15 #include "internal/core.h"
16 #include "internal/property.h"
17 #include "internal/provider.h"
18 #include "crypto/ctype.h"
19 #include <openssl/lhash.h>
20 #include <openssl/rand.h>
21 #include "internal/thread_once.h"
22 #include "crypto/lhash.h"
23 #include "crypto/sparse_array.h"
24 #include "property_local.h"
27 * The number of elements in the query cache before we initiate a flush.
28 * If reducing this, also ensure the stochastic test in test/property_test.c
29 * isn't likely to fail.
31 #define IMPL_CACHE_FLUSH_THRESHOLD 500
35 int (*up_ref)(void *);
40 const OSSL_PROVIDER *provider;
41 OSSL_PROPERTY_LIST *properties;
45 DEFINE_STACK_OF(IMPLEMENTATION)
53 DEFINE_LHASH_OF(QUERY);
57 STACK_OF(IMPLEMENTATION) *impls;
58 LHASH_OF(QUERY) *cache;
61 struct ossl_method_store_st {
64 SPARSE_ARRAY_OF(ALGORITHM) *algs;
70 LHASH_OF(QUERY) *cache;
75 DEFINE_SPARSE_ARRAY_OF(ALGORITHM);
77 typedef struct ossl_global_properties_st {
78 OSSL_PROPERTY_LIST *list;
80 unsigned int no_mirrored : 1;
82 } OSSL_GLOBAL_PROPERTIES;
84 static void ossl_method_cache_flush(OSSL_METHOD_STORE *store, int nid);
86 /* Global properties are stored per library context */
87 static void ossl_ctx_global_properties_free(void *vglobp)
89 OSSL_GLOBAL_PROPERTIES *globp = vglobp;
92 ossl_property_free(globp->list);
97 static void *ossl_ctx_global_properties_new(OSSL_LIB_CTX *ctx)
99 return OPENSSL_zalloc(sizeof(OSSL_GLOBAL_PROPERTIES));
102 static const OSSL_LIB_CTX_METHOD ossl_ctx_global_properties_method = {
103 OSSL_LIB_CTX_METHOD_DEFAULT_PRIORITY,
104 ossl_ctx_global_properties_new,
105 ossl_ctx_global_properties_free,
108 OSSL_PROPERTY_LIST **ossl_ctx_global_properties(OSSL_LIB_CTX *libctx,
111 OSSL_GLOBAL_PROPERTIES *globp;
114 if (loadconfig && !OPENSSL_init_crypto(OPENSSL_INIT_LOAD_CONFIG, NULL))
117 globp = ossl_lib_ctx_get_data(libctx, OSSL_LIB_CTX_GLOBAL_PROPERTIES,
118 &ossl_ctx_global_properties_method);
124 int ossl_global_properties_no_mirrored(OSSL_LIB_CTX *libctx)
126 OSSL_GLOBAL_PROPERTIES *globp
127 = ossl_lib_ctx_get_data(libctx, OSSL_LIB_CTX_GLOBAL_PROPERTIES,
128 &ossl_ctx_global_properties_method);
130 return globp->no_mirrored ? 1 : 0;
133 void ossl_global_properties_stop_mirroring(OSSL_LIB_CTX *libctx)
135 OSSL_GLOBAL_PROPERTIES *globp
136 = ossl_lib_ctx_get_data(libctx, OSSL_LIB_CTX_GLOBAL_PROPERTIES,
137 &ossl_ctx_global_properties_method);
139 globp->no_mirrored = 1;
143 static int ossl_method_up_ref(METHOD *method)
145 return (*method->up_ref)(method->method);
148 static void ossl_method_free(METHOD *method)
150 (*method->free)(method->method);
153 static __owur int ossl_property_read_lock(OSSL_METHOD_STORE *p)
155 return p != NULL ? CRYPTO_THREAD_read_lock(p->lock) : 0;
158 static __owur int ossl_property_write_lock(OSSL_METHOD_STORE *p)
160 return p != NULL ? CRYPTO_THREAD_write_lock(p->lock) : 0;
163 static int ossl_property_unlock(OSSL_METHOD_STORE *p)
165 return p != 0 ? CRYPTO_THREAD_unlock(p->lock) : 0;
168 static unsigned long query_hash(const QUERY *a)
170 return OPENSSL_LH_strhash(a->query);
173 static int query_cmp(const QUERY *a, const QUERY *b)
175 return strcmp(a->query, b->query);
178 static void impl_free(IMPLEMENTATION *impl)
181 ossl_method_free(&impl->method);
186 static void impl_cache_free(QUERY *elem)
189 ossl_method_free(&elem->method);
194 static void alg_cleanup(ossl_uintmax_t idx, ALGORITHM *a)
197 sk_IMPLEMENTATION_pop_free(a->impls, &impl_free);
198 lh_QUERY_doall(a->cache, &impl_cache_free);
199 lh_QUERY_free(a->cache);
205 * The OSSL_LIB_CTX param here allows access to underlying property data needed
208 OSSL_METHOD_STORE *ossl_method_store_new(OSSL_LIB_CTX *ctx)
210 OSSL_METHOD_STORE *res;
212 res = OPENSSL_zalloc(sizeof(*res));
215 if ((res->algs = ossl_sa_ALGORITHM_new()) == NULL) {
219 if ((res->lock = CRYPTO_THREAD_lock_new()) == NULL) {
220 ossl_sa_ALGORITHM_free(res->algs);
228 void ossl_method_store_free(OSSL_METHOD_STORE *store)
231 ossl_sa_ALGORITHM_doall(store->algs, &alg_cleanup);
232 ossl_sa_ALGORITHM_free(store->algs);
233 CRYPTO_THREAD_lock_free(store->lock);
238 static ALGORITHM *ossl_method_store_retrieve(OSSL_METHOD_STORE *store, int nid)
240 return ossl_sa_ALGORITHM_get(store->algs, nid);
243 static int ossl_method_store_insert(OSSL_METHOD_STORE *store, ALGORITHM *alg)
245 return ossl_sa_ALGORITHM_set(store->algs, alg->nid, alg);
248 int ossl_method_store_add(OSSL_METHOD_STORE *store, const OSSL_PROVIDER *prov,
249 int nid, const char *properties, void *method,
250 int (*method_up_ref)(void *),
251 void (*method_destruct)(void *))
253 ALGORITHM *alg = NULL;
254 IMPLEMENTATION *impl;
258 if (nid <= 0 || method == NULL || store == NULL)
260 if (properties == NULL)
263 /* Create new entry */
264 impl = OPENSSL_malloc(sizeof(*impl));
267 impl->method.method = method;
268 impl->method.up_ref = method_up_ref;
269 impl->method.free = method_destruct;
270 if (!ossl_method_up_ref(&impl->method)) {
274 impl->provider = prov;
277 * Insert into the hash table if required.
279 * A write lock is used unconditionally because we wend our way down to the
280 * property string code which isn't locking friendly.
282 if (!ossl_property_write_lock(store)) {
286 ossl_method_cache_flush(store, nid);
287 if ((impl->properties = ossl_prop_defn_get(store->ctx, properties)) == NULL) {
288 impl->properties = ossl_parse_property(store->ctx, properties);
289 if (impl->properties == NULL)
291 ossl_prop_defn_set(store->ctx, properties, impl->properties);
294 alg = ossl_method_store_retrieve(store, nid);
296 if ((alg = OPENSSL_zalloc(sizeof(*alg))) == NULL
297 || (alg->impls = sk_IMPLEMENTATION_new_null()) == NULL
298 || (alg->cache = lh_QUERY_new(&query_hash, &query_cmp)) == NULL)
301 if (!ossl_method_store_insert(store, alg))
305 /* Push onto stack if there isn't one there already */
306 for (i = 0; i < sk_IMPLEMENTATION_num(alg->impls); i++) {
307 const IMPLEMENTATION *tmpimpl = sk_IMPLEMENTATION_value(alg->impls, i);
309 if (tmpimpl->provider == impl->provider
310 && tmpimpl->properties == impl->properties)
313 if (i == sk_IMPLEMENTATION_num(alg->impls)
314 && sk_IMPLEMENTATION_push(alg->impls, impl))
316 ossl_property_unlock(store);
322 ossl_property_unlock(store);
328 int ossl_method_store_remove(OSSL_METHOD_STORE *store, int nid,
331 ALGORITHM *alg = NULL;
334 if (nid <= 0 || method == NULL || store == NULL)
337 if (!ossl_property_write_lock(store))
339 ossl_method_cache_flush(store, nid);
340 alg = ossl_method_store_retrieve(store, nid);
342 ossl_property_unlock(store);
347 * A sorting find then a delete could be faster but these stacks should be
348 * relatively small, so we avoid the overhead. Sorting could also surprise
349 * users when result orderings change (even though they are not guaranteed).
351 for (i = 0; i < sk_IMPLEMENTATION_num(alg->impls); i++) {
352 IMPLEMENTATION *impl = sk_IMPLEMENTATION_value(alg->impls, i);
354 if (impl->method.method == method) {
356 (void)sk_IMPLEMENTATION_delete(alg->impls, i);
357 ossl_property_unlock(store);
361 ossl_property_unlock(store);
365 static void alg_do_one(ALGORITHM *alg, IMPLEMENTATION *impl,
366 void (*fn)(int id, void *method, void *fnarg),
369 fn(alg->nid, impl->method.method, fnarg);
372 struct alg_do_each_data_st {
373 void (*fn)(int id, void *method, void *fnarg);
377 static void alg_do_each(ossl_uintmax_t idx, ALGORITHM *alg, void *arg)
379 struct alg_do_each_data_st *data = arg;
380 int i, end = sk_IMPLEMENTATION_num(alg->impls);
382 for (i = 0; i < end; i++) {
383 IMPLEMENTATION *impl = sk_IMPLEMENTATION_value(alg->impls, i);
385 alg_do_one(alg, impl, data->fn, data->fnarg);
389 void ossl_method_store_do_all(OSSL_METHOD_STORE *store,
390 void (*fn)(int id, void *method, void *fnarg),
393 struct alg_do_each_data_st data;
398 ossl_sa_ALGORITHM_doall_arg(store->algs, alg_do_each, &data);
401 int ossl_method_store_fetch(OSSL_METHOD_STORE *store, int nid,
402 const char *prop_query,
405 OSSL_PROPERTY_LIST **plp;
407 IMPLEMENTATION *impl;
408 OSSL_PROPERTY_LIST *pq = NULL, *p2 = NULL;
409 METHOD *best_method = NULL;
411 int j, best = -1, score, optional;
414 if (!OPENSSL_init_crypto(OPENSSL_INIT_LOAD_CONFIG, NULL))
418 if (nid <= 0 || method == NULL || store == NULL)
422 * This only needs to be a read lock, because queries never create property
423 * names or value and thus don't modify any of the property string layer.
425 if (!ossl_property_read_lock(store))
427 alg = ossl_method_store_retrieve(store, nid);
429 ossl_property_unlock(store);
433 if (prop_query != NULL)
434 p2 = pq = ossl_parse_query(store->ctx, prop_query, 0);
435 plp = ossl_ctx_global_properties(store->ctx, 0);
436 if (plp != NULL && *plp != NULL) {
440 p2 = ossl_property_merge(pq, *plp);
441 ossl_property_free(pq);
449 if ((impl = sk_IMPLEMENTATION_value(alg->impls, 0)) != NULL) {
450 best_method = &impl->method;
455 optional = ossl_property_has_optional(pq);
456 for (j = 0; j < sk_IMPLEMENTATION_num(alg->impls); j++) {
457 impl = sk_IMPLEMENTATION_value(alg->impls, j);
458 score = ossl_property_match_count(pq, impl->properties);
460 best_method = &impl->method;
468 if (ret && ossl_method_up_ref(best_method))
469 *method = best_method->method;
472 ossl_property_unlock(store);
473 ossl_property_free(p2);
477 static void impl_cache_flush_alg(ossl_uintmax_t idx, ALGORITHM *alg, void *arg)
479 SPARSE_ARRAY_OF(ALGORITHM) *algs = arg;
481 lh_QUERY_doall(alg->cache, &impl_cache_free);
483 sk_IMPLEMENTATION_pop_free(alg->impls, &impl_free);
484 lh_QUERY_free(alg->cache);
486 ossl_sa_ALGORITHM_set(algs, idx, NULL);
488 lh_QUERY_flush(alg->cache);
492 static void ossl_method_cache_flush(OSSL_METHOD_STORE *store, int nid)
494 ALGORITHM *alg = ossl_method_store_retrieve(store, nid);
497 ossl_provider_clear_all_operation_bits(store->ctx);
498 store->nelem -= lh_QUERY_num_items(alg->cache);
499 impl_cache_flush_alg(0, alg, NULL);
503 int ossl_method_store_flush_cache(OSSL_METHOD_STORE *store, int all)
505 void *arg = (all != 0 ? store->algs : NULL);
507 if (!ossl_property_write_lock(store))
509 ossl_provider_clear_all_operation_bits(store->ctx);
510 ossl_sa_ALGORITHM_doall_arg(store->algs, &impl_cache_flush_alg, arg);
512 ossl_property_unlock(store);
516 IMPLEMENT_LHASH_DOALL_ARG(QUERY, IMPL_CACHE_FLUSH);
519 * Flush an element from the query cache (perhaps).
521 * In order to avoid taking a write lock or using atomic operations
522 * to keep accurate least recently used (LRU) or least frequently used
523 * (LFU) information, the procedure used here is to stochastically
524 * flush approximately half the cache.
526 * This procedure isn't ideal, LRU or LFU would be better. However,
527 * in normal operation, reaching a full cache would be unexpected.
528 * It means that no steady state of algorithm queries has been reached.
529 * That is, it is most likely an attack of some form. A suboptimal clearance
530 * strategy that doesn't degrade performance of the normal case is
531 * preferable to a more refined approach that imposes a performance
534 static void impl_cache_flush_cache(QUERY *c, IMPL_CACHE_FLUSH *state)
539 * Implement the 32 bit xorshift as suggested by George Marsaglia in:
540 * https://doi.org/10.18637/jss.v008.i14
542 * This is a very fast PRNG so there is no need to extract bits one at a
543 * time and use the entire value each time.
552 impl_cache_free(lh_QUERY_delete(state->cache, c));
557 static void impl_cache_flush_one_alg(ossl_uintmax_t idx, ALGORITHM *alg,
560 IMPL_CACHE_FLUSH *state = (IMPL_CACHE_FLUSH *)v;
562 state->cache = alg->cache;
563 lh_QUERY_doall_IMPL_CACHE_FLUSH(state->cache, &impl_cache_flush_cache,
567 static void ossl_method_cache_flush_some(OSSL_METHOD_STORE *store)
569 IMPL_CACHE_FLUSH state;
572 if ((state.seed = OPENSSL_rdtsc()) == 0)
574 ossl_provider_clear_all_operation_bits(store->ctx);
575 store->need_flush = 0;
576 ossl_sa_ALGORITHM_doall_arg(store->algs, &impl_cache_flush_one_alg, &state);
577 store->nelem = state.nelem;
580 int ossl_method_store_cache_get(OSSL_METHOD_STORE *store, int nid,
581 const char *prop_query, void **method)
587 if (nid <= 0 || store == NULL)
590 if (!ossl_property_read_lock(store))
592 alg = ossl_method_store_retrieve(store, nid);
596 elem.query = prop_query != NULL ? prop_query : "";
597 r = lh_QUERY_retrieve(alg->cache, &elem);
600 if (ossl_method_up_ref(&r->method)) {
601 *method = r->method.method;
605 ossl_property_unlock(store);
609 int ossl_method_store_cache_set(OSSL_METHOD_STORE *store, int nid,
610 const char *prop_query, void *method,
611 int (*method_up_ref)(void *),
612 void (*method_destruct)(void *))
614 QUERY elem, *old, *p = NULL;
619 if (nid <= 0 || store == NULL)
621 if (prop_query == NULL)
624 if (!ossl_property_write_lock(store))
626 if (store->need_flush)
627 ossl_method_cache_flush_some(store);
628 alg = ossl_method_store_retrieve(store, nid);
632 if (method == NULL) {
633 elem.query = prop_query;
634 if ((old = lh_QUERY_delete(alg->cache, &elem)) != NULL) {
635 impl_cache_free(old);
640 p = OPENSSL_malloc(sizeof(*p) + (len = strlen(prop_query)));
643 p->method.method = method;
644 p->method.up_ref = method_up_ref;
645 p->method.free = method_destruct;
646 if (!ossl_method_up_ref(&p->method))
648 memcpy((char *)p->query, prop_query, len + 1);
649 if ((old = lh_QUERY_insert(alg->cache, p)) != NULL) {
650 impl_cache_free(old);
653 if (!lh_QUERY_error(alg->cache)) {
654 if (++store->nelem >= IMPL_CACHE_FLUSH_THRESHOLD)
655 store->need_flush = 1;
658 ossl_method_free(&p->method);
664 ossl_property_unlock(store);