crypto/property/property.c

   1 /*
   2  * Copyright 2019-2022 The OpenSSL Project Authors. All Rights Reserved.
   3  * Copyright (c) 2019, 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 <string.h>
  12 #include <stdio.h>
  13 #include <stdarg.h>
  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"
  25 #include "crypto/context.h"
  26
  27 /*
  28  * The number of elements in the query cache before we initiate a flush.
  29  * If reducing this, also ensure the stochastic test in test/property_test.c
  30  * isn't likely to fail.
  31  */
  32 #define IMPL_CACHE_FLUSH_THRESHOLD  500
  33
  34 typedef struct {
  35     void *method;
  36     int (*up_ref)(void *);
  37     void (*free)(void *);
  38 } METHOD;
  39
  40 typedef struct {
  41     const OSSL_PROVIDER *provider;
  42     OSSL_PROPERTY_LIST *properties;
  43     METHOD method;
  44 } IMPLEMENTATION;
  45
  46 DEFINE_STACK_OF(IMPLEMENTATION)
  47
  48 typedef struct {
  49     const OSSL_PROVIDER *provider;
  50     const char *query;
  51     METHOD method;
  52     char body[1];
  53 } QUERY;
  54
  55 DEFINE_LHASH_OF_EX(QUERY);
  56
  57 typedef struct {
  58     int nid;
  59     STACK_OF(IMPLEMENTATION) *impls;
  60     LHASH_OF(QUERY) *cache;
  61 } ALGORITHM;
  62
  63 struct ossl_method_store_st {
  64     OSSL_LIB_CTX *ctx;
  65     SPARSE_ARRAY_OF(ALGORITHM) *algs;
  66     CRYPTO_RWLOCK *lock;
  67
  68     /* query cache specific values */
  69
  70     /* Count of the query cache entries for all algs */
  71     size_t cache_nelem;
  72
  73     /* Flag: 1 if query cache entries for all algs need flushing */
  74     int cache_need_flush;
  75 };
  76
  77 typedef struct {
  78     LHASH_OF(QUERY) *cache;
  79     size_t nelem;
  80     uint32_t seed;
  81 } IMPL_CACHE_FLUSH;
  82
  83 DEFINE_SPARSE_ARRAY_OF(ALGORITHM);
  84
  85 typedef struct ossl_global_properties_st {
  86     OSSL_PROPERTY_LIST *list;
  87 #ifndef FIPS_MODULE
  88     unsigned int no_mirrored : 1;
  89 #endif
  90 } OSSL_GLOBAL_PROPERTIES;
  91
  92 static void ossl_method_cache_flush_alg(OSSL_METHOD_STORE *store,
  93                                         ALGORITHM *alg);
  94 static void ossl_method_cache_flush(OSSL_METHOD_STORE *store, int nid);
  95
  96 /* Global properties are stored per library context */
  97 void ossl_ctx_global_properties_free(void *vglobp)
  98 {
  99     OSSL_GLOBAL_PROPERTIES *globp = vglobp;
 100
 101     if (globp != NULL) {
 102         ossl_property_free(globp->list);
 103         OPENSSL_free(globp);
 104     }
 105 }
 106
 107 void *ossl_ctx_global_properties_new(OSSL_LIB_CTX *ctx)
 108 {
 109     return OPENSSL_zalloc(sizeof(OSSL_GLOBAL_PROPERTIES));
 110 }
 111
 112 OSSL_PROPERTY_LIST **ossl_ctx_global_properties(OSSL_LIB_CTX *libctx,
 113                                                 int loadconfig)
 114 {
 115     OSSL_GLOBAL_PROPERTIES *globp;
 116
 117 #ifndef FIPS_MODULE
 118     if (loadconfig && !OPENSSL_init_crypto(OPENSSL_INIT_LOAD_CONFIG, NULL))
 119         return NULL;
 120 #endif
 121     globp = ossl_lib_ctx_get_data(libctx, OSSL_LIB_CTX_GLOBAL_PROPERTIES);
 122
 123     return globp != NULL ? &globp->list : NULL;
 124 }
 125
 126 #ifndef FIPS_MODULE
 127 int ossl_global_properties_no_mirrored(OSSL_LIB_CTX *libctx)
 128 {
 129     OSSL_GLOBAL_PROPERTIES *globp
 130         = ossl_lib_ctx_get_data(libctx, OSSL_LIB_CTX_GLOBAL_PROPERTIES);
 131
 132     return globp != NULL && globp->no_mirrored ? 1 : 0;
 133 }
 134
 135 void ossl_global_properties_stop_mirroring(OSSL_LIB_CTX *libctx)
 136 {
 137     OSSL_GLOBAL_PROPERTIES *globp
 138         = ossl_lib_ctx_get_data(libctx, OSSL_LIB_CTX_GLOBAL_PROPERTIES);
 139
 140     if (globp != NULL)
 141         globp->no_mirrored = 1;
 142 }
 143 #endif
 144
 145 static int ossl_method_up_ref(METHOD *method)
 146 {
 147     return (*method->up_ref)(method->method);
 148 }
 149
 150 static void ossl_method_free(METHOD *method)
 151 {
 152     (*method->free)(method->method);
 153 }
 154
 155 static __owur int ossl_property_read_lock(OSSL_METHOD_STORE *p)
 156 {
 157     return p != NULL ? CRYPTO_THREAD_read_lock(p->lock) : 0;
 158 }
 159
 160 static __owur int ossl_property_write_lock(OSSL_METHOD_STORE *p)
 161 {
 162     return p != NULL ? CRYPTO_THREAD_write_lock(p->lock) : 0;
 163 }
 164
 165 static int ossl_property_unlock(OSSL_METHOD_STORE *p)
 166 {
 167     return p != 0 ? CRYPTO_THREAD_unlock(p->lock) : 0;
 168 }
 169
 170 static unsigned long query_hash(const QUERY *a)
 171 {
 172     return OPENSSL_LH_strhash(a->query);
 173 }
 174
 175 static int query_cmp(const QUERY *a, const QUERY *b)
 176 {
 177     int res = strcmp(a->query, b->query);
 178
 179     if (res == 0 && a->provider != NULL && b->provider != NULL)
 180         res = b->provider > a->provider ? 1
 181             : b->provider < a->provider ? -1
 182             : 0;
 183     return res;
 184 }
 185
 186 static void impl_free(IMPLEMENTATION *impl)
 187 {
 188     if (impl != NULL) {
 189         ossl_method_free(&impl->method);
 190         OPENSSL_free(impl);
 191     }
 192 }
 193
 194 static void impl_cache_free(QUERY *elem)
 195 {
 196     if (elem != NULL) {
 197         ossl_method_free(&elem->method);
 198         OPENSSL_free(elem);
 199     }
 200 }
 201
 202 static void impl_cache_flush_alg(ossl_uintmax_t idx, ALGORITHM *alg)
 203 {
 204     lh_QUERY_doall(alg->cache, &impl_cache_free);
 205     lh_QUERY_flush(alg->cache);
 206 }
 207
 208 static void alg_cleanup(ossl_uintmax_t idx, ALGORITHM *a, void *arg)
 209 {
 210     OSSL_METHOD_STORE *store = arg;
 211
 212     if (a != NULL) {
 213         sk_IMPLEMENTATION_pop_free(a->impls, &impl_free);
 214         lh_QUERY_doall(a->cache, &impl_cache_free);
 215         lh_QUERY_free(a->cache);
 216         OPENSSL_free(a);
 217     }
 218     if (store != NULL)
 219         ossl_sa_ALGORITHM_set(store->algs, idx, NULL);
 220 }
 221
 222 /*
 223  * The OSSL_LIB_CTX param here allows access to underlying property data needed
 224  * for computation
 225  */
 226 OSSL_METHOD_STORE *ossl_method_store_new(OSSL_LIB_CTX *ctx)
 227 {
 228     OSSL_METHOD_STORE *res;
 229
 230     res = OPENSSL_zalloc(sizeof(*res));
 231     if (res != NULL) {
 232         res->ctx = ctx;
 233         if ((res->algs = ossl_sa_ALGORITHM_new()) == NULL) {
 234             OPENSSL_free(res);
 235             return NULL;
 236         }
 237         if ((res->lock = CRYPTO_THREAD_lock_new()) == NULL) {
 238             ossl_sa_ALGORITHM_free(res->algs);
 239             OPENSSL_free(res);
 240             return NULL;
 241         }
 242     }
 243     return res;
 244 }
 245
 246 void ossl_method_store_free(OSSL_METHOD_STORE *store)
 247 {
 248     if (store != NULL) {
 249         ossl_sa_ALGORITHM_doall_arg(store->algs, &alg_cleanup, store);
 250         ossl_sa_ALGORITHM_free(store->algs);
 251         CRYPTO_THREAD_lock_free(store->lock);
 252         OPENSSL_free(store);
 253     }
 254 }
 255
 256 static ALGORITHM *ossl_method_store_retrieve(OSSL_METHOD_STORE *store, int nid)
 257 {
 258     return ossl_sa_ALGORITHM_get(store->algs, nid);
 259 }
 260
 261 static int ossl_method_store_insert(OSSL_METHOD_STORE *store, ALGORITHM *alg)
 262 {
 263         return ossl_sa_ALGORITHM_set(store->algs, alg->nid, alg);
 264 }
 265
 266 int ossl_method_store_add(OSSL_METHOD_STORE *store, const OSSL_PROVIDER *prov,
 267                           int nid, const char *properties, void *method,
 268                           int (*method_up_ref)(void *),
 269                           void (*method_destruct)(void *))
 270 {
 271     ALGORITHM *alg = NULL;
 272     IMPLEMENTATION *impl;
 273     int ret = 0;
 274     int i;
 275
 276     if (nid <= 0 || method == NULL || store == NULL)
 277         return 0;
 278     if (properties == NULL)
 279         properties = "";
 280
 281     if (!ossl_assert(prov != NULL))
 282         return 0;
 283
 284     /* Create new entry */
 285     impl = OPENSSL_malloc(sizeof(*impl));
 286     if (impl == NULL)
 287         return 0;
 288     impl->method.method = method;
 289     impl->method.up_ref = method_up_ref;
 290     impl->method.free = method_destruct;
 291     if (!ossl_method_up_ref(&impl->method)) {
 292         OPENSSL_free(impl);
 293         return 0;
 294     }
 295     impl->provider = prov;
 296
 297     /* Insert into the hash table if required */
 298     if (!ossl_property_write_lock(store)) {
 299         OPENSSL_free(impl);
 300         return 0;
 301     }
 302     ossl_method_cache_flush(store, nid);
 303     if ((impl->properties = ossl_prop_defn_get(store->ctx, properties)) == NULL) {
 304         impl->properties = ossl_parse_property(store->ctx, properties);
 305         if (impl->properties == NULL)
 306             goto err;
 307         if (!ossl_prop_defn_set(store->ctx, properties, impl->properties)) {
 308             ossl_property_free(impl->properties);
 309             impl->properties = NULL;
 310             goto err;
 311         }
 312     }
 313
 314     alg = ossl_method_store_retrieve(store, nid);
 315     if (alg == NULL) {
 316         if ((alg = OPENSSL_zalloc(sizeof(*alg))) == NULL
 317                 || (alg->impls = sk_IMPLEMENTATION_new_null()) == NULL
 318                 || (alg->cache = lh_QUERY_new(&query_hash, &query_cmp)) == NULL)
 319             goto err;
 320         alg->nid = nid;
 321         if (!ossl_method_store_insert(store, alg))
 322             goto err;
 323     }
 324
 325     /* Push onto stack if there isn't one there already */
 326     for (i = 0; i < sk_IMPLEMENTATION_num(alg->impls); i++) {
 327         const IMPLEMENTATION *tmpimpl = sk_IMPLEMENTATION_value(alg->impls, i);
 328
 329         if (tmpimpl->provider == impl->provider
 330             && tmpimpl->properties == impl->properties)
 331             break;
 332     }
 333     if (i == sk_IMPLEMENTATION_num(alg->impls)
 334         && sk_IMPLEMENTATION_push(alg->impls, impl))
 335         ret = 1;
 336     ossl_property_unlock(store);
 337     if (ret == 0)
 338         impl_free(impl);
 339     return ret;
 340
 341 err:
 342     ossl_property_unlock(store);
 343     alg_cleanup(0, alg, NULL);
 344     impl_free(impl);
 345     return 0;
 346 }
 347
 348 int ossl_method_store_remove(OSSL_METHOD_STORE *store, int nid,
 349                              const void *method)
 350 {
 351     ALGORITHM *alg = NULL;
 352     int i;
 353
 354     if (nid <= 0 || method == NULL || store == NULL)
 355         return 0;
 356
 357     if (!ossl_property_write_lock(store))
 358         return 0;
 359     ossl_method_cache_flush(store, nid);
 360     alg = ossl_method_store_retrieve(store, nid);
 361     if (alg == NULL) {
 362         ossl_property_unlock(store);
 363         return 0;
 364     }
 365
 366     /*
 367      * A sorting find then a delete could be faster but these stacks should be
 368      * relatively small, so we avoid the overhead.  Sorting could also surprise
 369      * users when result orderings change (even though they are not guaranteed).
 370      */
 371     for (i = 0; i < sk_IMPLEMENTATION_num(alg->impls); i++) {
 372         IMPLEMENTATION *impl = sk_IMPLEMENTATION_value(alg->impls, i);
 373
 374         if (impl->method.method == method) {
 375             impl_free(impl);
 376             (void)sk_IMPLEMENTATION_delete(alg->impls, i);
 377             ossl_property_unlock(store);
 378             return 1;
 379         }
 380     }
 381     ossl_property_unlock(store);
 382     return 0;
 383 }
 384
 385 struct alg_cleanup_by_provider_data_st {
 386     OSSL_METHOD_STORE *store;
 387     const OSSL_PROVIDER *prov;
 388 };
 389
 390 static void
 391 alg_cleanup_by_provider(ossl_uintmax_t idx, ALGORITHM *alg, void *arg)
 392 {
 393     struct alg_cleanup_by_provider_data_st *data = arg;
 394     int i, count;
 395
 396     /*
 397      * We walk the stack backwards, to avoid having to deal with stack shifts
 398      * caused by deletion
 399      */
 400     for (count = 0, i = sk_IMPLEMENTATION_num(alg->impls); i-- > 0;) {
 401         IMPLEMENTATION *impl = sk_IMPLEMENTATION_value(alg->impls, i);
 402
 403         if (impl->provider == data->prov) {
 404             impl_free(impl);
 405             (void)sk_IMPLEMENTATION_delete(alg->impls, i);
 406             count++;
 407         }
 408     }
 409
 410     /*
 411      * If we removed any implementation, we also clear the whole associated
 412      * cache, 'cause that's the sensible thing to do.
 413      * There's no point flushing the cache entries where we didn't remove
 414      * any implementation, though.
 415      */
 416     if (count > 0)
 417         ossl_method_cache_flush_alg(data->store, alg);
 418 }
 419
 420 int ossl_method_store_remove_all_provided(OSSL_METHOD_STORE *store,
 421                                           const OSSL_PROVIDER *prov)
 422 {
 423     struct alg_cleanup_by_provider_data_st data;
 424
 425     if (!ossl_property_write_lock(store))
 426         return 0;
 427     data.prov = prov;
 428     data.store = store;
 429     ossl_sa_ALGORITHM_doall_arg(store->algs, &alg_cleanup_by_provider, &data);
 430     ossl_property_unlock(store);
 431     return 1;
 432 }
 433
 434 static void alg_do_one(ALGORITHM *alg, IMPLEMENTATION *impl,
 435                        void (*fn)(int id, void *method, void *fnarg),
 436                        void *fnarg)
 437 {
 438     fn(alg->nid, impl->method.method, fnarg);
 439 }
 440
 441 struct alg_do_each_data_st {
 442     void (*fn)(int id, void *method, void *fnarg);
 443     void *fnarg;
 444 };
 445
 446 static void alg_do_each(ossl_uintmax_t idx, ALGORITHM *alg, void *arg)
 447 {
 448     struct alg_do_each_data_st *data = arg;
 449     int i, end = sk_IMPLEMENTATION_num(alg->impls);
 450
 451     for (i = 0; i < end; i++) {
 452         IMPLEMENTATION *impl = sk_IMPLEMENTATION_value(alg->impls, i);
 453
 454         alg_do_one(alg, impl, data->fn, data->fnarg);
 455     }
 456 }
 457
 458 void ossl_method_store_do_all(OSSL_METHOD_STORE *store,
 459                               void (*fn)(int id, void *method, void *fnarg),
 460                               void *fnarg)
 461 {
 462     struct alg_do_each_data_st data;
 463
 464     data.fn = fn;
 465     data.fnarg = fnarg;
 466     if (store != NULL)
 467         ossl_sa_ALGORITHM_doall_arg(store->algs, alg_do_each, &data);
 468 }
 469
 470 int ossl_method_store_fetch(OSSL_METHOD_STORE *store,
 471                             int nid, const char *prop_query,
 472                             const OSSL_PROVIDER **prov_rw, void **method)
 473 {
 474     OSSL_PROPERTY_LIST **plp;
 475     ALGORITHM *alg;
 476     IMPLEMENTATION *impl, *best_impl = NULL;
 477     OSSL_PROPERTY_LIST *pq = NULL, *p2 = NULL;
 478     const OSSL_PROVIDER *prov = prov_rw != NULL ? *prov_rw : NULL;
 479     int ret = 0;
 480     int j, best = -1, score, optional;
 481
 482 #ifndef FIPS_MODULE
 483     if (!OPENSSL_init_crypto(OPENSSL_INIT_LOAD_CONFIG, NULL))
 484         return 0;
 485 #endif
 486
 487     if (nid <= 0 || method == NULL || store == NULL)
 488         return 0;
 489
 490     /* This only needs to be a read lock, because the query won't create anything */
 491     if (!ossl_property_read_lock(store))
 492         return 0;
 493     alg = ossl_method_store_retrieve(store, nid);
 494     if (alg == NULL) {
 495         ossl_property_unlock(store);
 496         return 0;
 497     }
 498
 499     if (prop_query != NULL)
 500         p2 = pq = ossl_parse_query(store->ctx, prop_query, 0);
 501     plp = ossl_ctx_global_properties(store->ctx, 0);
 502     if (plp != NULL && *plp != NULL) {
 503         if (pq == NULL) {
 504             pq = *plp;
 505         } else {
 506             p2 = ossl_property_merge(pq, *plp);
 507             ossl_property_free(pq);
 508             if (p2 == NULL)
 509                 goto fin;
 510             pq = p2;
 511         }
 512     }
 513
 514     if (pq == NULL) {
 515         for (j = 0; j < sk_IMPLEMENTATION_num(alg->impls); j++) {
 516             if ((impl = sk_IMPLEMENTATION_value(alg->impls, j)) != NULL
 517                 && (prov == NULL || impl->provider == prov)) {
 518                 best_impl = impl;
 519                 ret = 1;
 520                 break;
 521             }
 522         }
 523         goto fin;
 524     }
 525     optional = ossl_property_has_optional(pq);
 526     for (j = 0; j < sk_IMPLEMENTATION_num(alg->impls); j++) {
 527         if ((impl = sk_IMPLEMENTATION_value(alg->impls, j)) != NULL
 528             && (prov == NULL || impl->provider == prov)) {
 529             score = ossl_property_match_count(pq, impl->properties);
 530             if (score > best) {
 531                 best_impl = impl;
 532                 best = score;
 533                 ret = 1;
 534                 if (!optional)
 535                     goto fin;
 536             }
 537         }
 538     }
 539 fin:
 540     if (ret && ossl_method_up_ref(&best_impl->method)) {
 541         *method = best_impl->method.method;
 542         if (prov_rw != NULL)
 543             *prov_rw = best_impl->provider;
 544     } else {
 545         ret = 0;
 546     }
 547     ossl_property_unlock(store);
 548     ossl_property_free(p2);
 549     return ret;
 550 }
 551
 552 static void ossl_method_cache_flush_alg(OSSL_METHOD_STORE *store,
 553                                         ALGORITHM *alg)
 554 {
 555     store->cache_nelem -= lh_QUERY_num_items(alg->cache);
 556     impl_cache_flush_alg(0, alg);
 557 }
 558
 559 static void ossl_method_cache_flush(OSSL_METHOD_STORE *store, int nid)
 560 {
 561     ALGORITHM *alg = ossl_method_store_retrieve(store, nid);
 562
 563     if (alg != NULL)
 564         ossl_method_cache_flush_alg(store, alg);
 565 }
 566
 567 int ossl_method_store_cache_flush_all(OSSL_METHOD_STORE *store)
 568 {
 569     if (!ossl_property_write_lock(store))
 570         return 0;
 571     ossl_sa_ALGORITHM_doall(store->algs, &impl_cache_flush_alg);
 572     store->cache_nelem = 0;
 573     ossl_property_unlock(store);
 574     return 1;
 575 }
 576
 577 IMPLEMENT_LHASH_DOALL_ARG(QUERY, IMPL_CACHE_FLUSH);
 578
 579 /*
 580  * Flush an element from the query cache (perhaps).
 581  *
 582  * In order to avoid taking a write lock or using atomic operations
 583  * to keep accurate least recently used (LRU) or least frequently used
 584  * (LFU) information, the procedure used here is to stochastically
 585  * flush approximately half the cache.
 586  *
 587  * This procedure isn't ideal, LRU or LFU would be better.  However,
 588  * in normal operation, reaching a full cache would be unexpected.
 589  * It means that no steady state of algorithm queries has been reached.
 590  * That is, it is most likely an attack of some form.  A suboptimal clearance
 591  * strategy that doesn't degrade performance of the normal case is
 592  * preferable to a more refined approach that imposes a performance
 593  * impact.
 594  */
 595 static void impl_cache_flush_cache(QUERY *c, IMPL_CACHE_FLUSH *state)
 596 {
 597     uint32_t n;
 598
 599     /*
 600      * Implement the 32 bit xorshift as suggested by George Marsaglia in:
 601      *      https://doi.org/10.18637/jss.v008.i14
 602      *
 603      * This is a very fast PRNG so there is no need to extract bits one at a
 604      * time and use the entire value each time.
 605      */
 606     n = state->seed;
 607     n ^= n << 13;
 608     n ^= n >> 17;
 609     n ^= n << 5;
 610     state->seed = n;
 611
 612     if ((n & 1) != 0)
 613         impl_cache_free(lh_QUERY_delete(state->cache, c));
 614     else
 615         state->nelem++;
 616 }
 617
 618 static void impl_cache_flush_one_alg(ossl_uintmax_t idx, ALGORITHM *alg,
 619                                      void *v)
 620 {
 621     IMPL_CACHE_FLUSH *state = (IMPL_CACHE_FLUSH *)v;
 622
 623     state->cache = alg->cache;
 624     lh_QUERY_doall_IMPL_CACHE_FLUSH(state->cache, &impl_cache_flush_cache,
 625                                     state);
 626 }
 627
 628 static void ossl_method_cache_flush_some(OSSL_METHOD_STORE *store)
 629 {
 630     IMPL_CACHE_FLUSH state;
 631
 632     state.nelem = 0;
 633     if ((state.seed = OPENSSL_rdtsc()) == 0)
 634         state.seed = 1;
 635     store->cache_need_flush = 0;
 636     ossl_sa_ALGORITHM_doall_arg(store->algs, &impl_cache_flush_one_alg, &state);
 637     store->cache_nelem = state.nelem;
 638 }
 639
 640 int ossl_method_store_cache_get(OSSL_METHOD_STORE *store, OSSL_PROVIDER *prov,
 641                                 int nid, const char *prop_query, void **method)
 642 {
 643     ALGORITHM *alg;
 644     QUERY elem, *r;
 645     int res = 0;
 646
 647     if (nid <= 0 || store == NULL || prop_query == NULL)
 648         return 0;
 649
 650     if (!ossl_property_read_lock(store))
 651         return 0;
 652     alg = ossl_method_store_retrieve(store, nid);
 653     if (alg == NULL)
 654         goto err;
 655
 656     elem.query = prop_query;
 657     elem.provider = prov;
 658     r = lh_QUERY_retrieve(alg->cache, &elem);
 659     if (r == NULL)
 660         goto err;
 661     if (ossl_method_up_ref(&r->method)) {
 662         *method = r->method.method;
 663         res = 1;
 664     }
 665 err:
 666     ossl_property_unlock(store);
 667     return res;
 668 }
 669
 670 int ossl_method_store_cache_set(OSSL_METHOD_STORE *store, OSSL_PROVIDER *prov,
 671                                 int nid, const char *prop_query, void *method,
 672                                 int (*method_up_ref)(void *),
 673                                 void (*method_destruct)(void *))
 674 {
 675     QUERY elem, *old, *p = NULL;
 676     ALGORITHM *alg;
 677     size_t len;
 678     int res = 1;
 679
 680     if (nid <= 0 || store == NULL || prop_query == NULL)
 681         return 0;
 682
 683     if (!ossl_assert(prov != NULL))
 684         return 0;
 685
 686     if (!ossl_property_write_lock(store))
 687         return 0;
 688     if (store->cache_need_flush)
 689         ossl_method_cache_flush_some(store);
 690     alg = ossl_method_store_retrieve(store, nid);
 691     if (alg == NULL)
 692         goto err;
 693
 694     if (method == NULL) {
 695         elem.query = prop_query;
 696         elem.provider = prov;
 697         if ((old = lh_QUERY_delete(alg->cache, &elem)) != NULL) {
 698             impl_cache_free(old);
 699             store->cache_nelem--;
 700         }
 701         goto end;
 702     }
 703     p = OPENSSL_malloc(sizeof(*p) + (len = strlen(prop_query)));
 704     if (p != NULL) {
 705         p->query = p->body;
 706         p->provider = prov;
 707         p->method.method = method;
 708         p->method.up_ref = method_up_ref;
 709         p->method.free = method_destruct;
 710         if (!ossl_method_up_ref(&p->method))
 711             goto err;
 712         memcpy((char *)p->query, prop_query, len + 1);
 713         if ((old = lh_QUERY_insert(alg->cache, p)) != NULL) {
 714             impl_cache_free(old);
 715             goto end;
 716         }
 717         if (!lh_QUERY_error(alg->cache)) {
 718             if (++store->cache_nelem >= IMPL_CACHE_FLUSH_THRESHOLD)
 719                 store->cache_need_flush = 1;
 720             goto end;
 721         }
 722         ossl_method_free(&p->method);
 723     }
 724 err:
 725     res = 0;
 726     OPENSSL_free(p);
 727 end:
 728     ossl_property_unlock(store);
 729     return res;
 730 }