crypto/provider_core.c

   1 /*
   2  * Copyright 2019 The OpenSSL Project Authors. All Rights Reserved.
   3  *
   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
   8  */
   9
  10 #include <openssl/core.h>
  11 #include <openssl/core_numbers.h>
  12 #include <openssl/params.h>
  13 #include <openssl/opensslv.h>
  14 #include "internal/cryptlib.h"
  15 #include "internal/nelem.h"
  16 #include "internal/thread_once.h"
  17 #include "internal/provider.h"
  18 #include "internal/refcount.h"
  19 #include "provider_local.h"
  20
  21 static OSSL_PROVIDER *provider_new(const char *name,
  22                                    OSSL_provider_init_fn *init_function);
  23
  24 /*-
  25  * Provider Object structure
  26  * =========================
  27  */
  28
  29 typedef struct {
  30     char *name;
  31     char *value;
  32 } INFOPAIR;
  33 DEFINE_STACK_OF(INFOPAIR)
  34
  35 struct provider_store_st;        /* Forward declaration */
  36
  37 struct ossl_provider_st {
  38     /* Flag bits */
  39     unsigned int flag_initialized:1;
  40     unsigned int flag_fallback:1;
  41
  42     /* OpenSSL library side data */
  43     CRYPTO_REF_COUNT refcnt;
  44     CRYPTO_RWLOCK *refcnt_lock;  /* For the ref counter */
  45     char *name;
  46     char *path;
  47     DSO *module;
  48     OSSL_provider_init_fn *init_function;
  49     STACK_OF(INFOPAIR) *parameters;
  50     struct provider_store_st *store; /* The store this instance belongs to */
  51
  52     /* Provider side functions */
  53     OSSL_provider_teardown_fn *teardown;
  54     OSSL_provider_get_param_types_fn *get_param_types;
  55     OSSL_provider_get_params_fn *get_params;
  56     OSSL_provider_query_operation_fn *query_operation;
  57
  58     /* Provider side data */
  59     void *provctx;
  60 };
  61 DEFINE_STACK_OF(OSSL_PROVIDER)
  62
  63 static int ossl_provider_cmp(const OSSL_PROVIDER * const *a,
  64                              const OSSL_PROVIDER * const *b)
  65 {
  66     return strcmp((*a)->name, (*b)->name);
  67 }
  68
  69 /*-
  70  * Provider Object store
  71  * =====================
  72  *
  73  * The Provider Object store is a library context object, and therefore needs
  74  * an index.
  75  */
  76
  77 struct provider_store_st {
  78     STACK_OF(OSSL_PROVIDER) *providers;
  79     CRYPTO_RWLOCK *lock;
  80     unsigned int use_fallbacks:1;
  81 };
  82
  83 static void provider_store_free(void *vstore)
  84 {
  85     struct provider_store_st *store = vstore;
  86
  87     if (store == NULL)
  88         return;
  89     sk_OSSL_PROVIDER_pop_free(store->providers, ossl_provider_free);
  90     CRYPTO_THREAD_lock_free(store->lock);
  91     OPENSSL_free(store);
  92 }
  93
  94 static void *provider_store_new(OPENSSL_CTX *ctx)
  95 {
  96     struct provider_store_st *store = OPENSSL_zalloc(sizeof(*store));
  97     const struct predefined_providers_st *p = NULL;
  98
  99     if (store == NULL
 100         || (store->providers = sk_OSSL_PROVIDER_new(ossl_provider_cmp)) == NULL
 101         || (store->lock = CRYPTO_THREAD_lock_new()) == NULL) {
 102         provider_store_free(store);
 103         return NULL;
 104     }
 105     store->use_fallbacks = 1;
 106
 107     for (p = predefined_providers; p->name != NULL; p++) {
 108         OSSL_PROVIDER *prov = NULL;
 109
 110         /*
 111          * We use the internal constructor directly here,
 112          * otherwise we get a call loop
 113          */
 114         prov = provider_new(p->name, p->init);
 115
 116         if (prov == NULL
 117             || sk_OSSL_PROVIDER_push(store->providers, prov) == 0) {
 118             ossl_provider_free(prov);
 119             provider_store_free(store);
 120             CRYPTOerr(CRYPTO_F_PROVIDER_STORE_NEW, ERR_R_INTERNAL_ERROR);
 121             return NULL;
 122         }
 123         prov->store = store;
 124         if(p->is_fallback)
 125             ossl_provider_set_fallback(prov);
 126     }
 127
 128     return store;
 129 }
 130
 131 static const OPENSSL_CTX_METHOD provider_store_method = {
 132     provider_store_new,
 133     provider_store_free,
 134 };
 135
 136 static struct provider_store_st *get_provider_store(OPENSSL_CTX *libctx)
 137 {
 138     struct provider_store_st *store = NULL;
 139
 140     store = openssl_ctx_get_data(libctx, OPENSSL_CTX_PROVIDER_STORE_INDEX,
 141                                  &provider_store_method);
 142     if (store == NULL)
 143         CRYPTOerr(CRYPTO_F_GET_PROVIDER_STORE, ERR_R_INTERNAL_ERROR);
 144     return store;
 145 }
 146
 147 OSSL_PROVIDER *ossl_provider_find(OPENSSL_CTX *libctx, const char *name)
 148 {
 149     struct provider_store_st *store = NULL;
 150     OSSL_PROVIDER *prov = NULL;
 151
 152     if ((store = get_provider_store(libctx)) != NULL) {
 153         OSSL_PROVIDER tmpl = { 0, };
 154         int i;
 155
 156         tmpl.name = (char *)name;
 157         CRYPTO_THREAD_write_lock(store->lock);
 158         if ((i = sk_OSSL_PROVIDER_find(store->providers, &tmpl)) == -1
 159             || (prov = sk_OSSL_PROVIDER_value(store->providers, i)) == NULL
 160             || !ossl_provider_upref(prov))
 161             prov = NULL;
 162         CRYPTO_THREAD_unlock(store->lock);
 163     }
 164
 165     return prov;
 166 }
 167
 168 /*-
 169  * Provider Object methods
 170  * =======================
 171  */
 172
 173 static OSSL_PROVIDER *provider_new(const char *name,
 174                                    OSSL_provider_init_fn *init_function)
 175 {
 176     OSSL_PROVIDER *prov = NULL;
 177
 178     if ((prov = OPENSSL_zalloc(sizeof(*prov))) == NULL
 179 #ifndef HAVE_ATOMICS
 180         || (prov->refcnt_lock = CRYPTO_THREAD_lock_new()) == NULL
 181 #endif
 182         || !ossl_provider_upref(prov) /* +1 One reference to be returned */
 183         || (prov->name = OPENSSL_strdup(name)) == NULL) {
 184         ossl_provider_free(prov);
 185         CRYPTOerr(CRYPTO_F_PROVIDER_NEW, ERR_R_MALLOC_FAILURE);
 186         return NULL;
 187     }
 188
 189     prov->init_function = init_function;
 190     return prov;
 191 }
 192
 193 int ossl_provider_upref(OSSL_PROVIDER *prov)
 194 {
 195     int ref = 0;
 196
 197     CRYPTO_UP_REF(&prov->refcnt, &ref, prov->refcnt_lock);
 198     return ref;
 199 }
 200
 201 OSSL_PROVIDER *ossl_provider_new(OPENSSL_CTX *libctx, const char *name,
 202                                  OSSL_provider_init_fn *init_function)
 203 {
 204     struct provider_store_st *store = NULL;
 205     OSSL_PROVIDER *prov = NULL;
 206
 207     if ((store = get_provider_store(libctx)) == NULL)
 208         return NULL;
 209
 210     if ((prov = ossl_provider_find(libctx, name)) != NULL) { /* refcount +1 */
 211         ossl_provider_free(prov); /* refcount -1 */
 212         CRYPTOerr(CRYPTO_F_OSSL_PROVIDER_NEW,
 213                   CRYPTO_R_PROVIDER_ALREADY_EXISTS);
 214         ERR_add_error_data(2, "name=", name);
 215         return NULL;
 216     }
 217
 218     /* provider_new() generates an error, so no need here */
 219     if ((prov = provider_new(name, init_function)) == NULL)
 220         return NULL;
 221
 222     CRYPTO_THREAD_write_lock(store->lock);
 223     if (!ossl_provider_upref(prov)) { /* +1 One reference for the store */
 224         ossl_provider_free(prov); /* -1 Reference that was to be returned */
 225         prov = NULL;
 226     } else if (sk_OSSL_PROVIDER_push(store->providers, prov) == 0) {
 227         ossl_provider_free(prov); /* -1 Store reference */
 228         ossl_provider_free(prov); /* -1 Reference that was to be returned */
 229         prov = NULL;
 230     } else {
 231         prov->store = store;
 232     }
 233     CRYPTO_THREAD_unlock(store->lock);
 234
 235     if (prov == NULL)
 236         CRYPTOerr(CRYPTO_F_OSSL_PROVIDER_NEW, ERR_R_MALLOC_FAILURE);
 237
 238     /*
 239      * At this point, the provider is only partially "loaded".  To be
 240      * fully "loaded", ossl_provider_activate() must also be called.
 241      */
 242
 243     return prov;
 244 }
 245
 246 static void free_infopair(INFOPAIR *pair)
 247 {
 248     OPENSSL_free(pair->name);
 249     OPENSSL_free(pair->value);
 250     OPENSSL_free(pair);
 251 }
 252
 253 void ossl_provider_free(OSSL_PROVIDER *prov)
 254 {
 255     if (prov != NULL) {
 256         int ref = 0;
 257
 258         CRYPTO_DOWN_REF(&prov->refcnt, &ref, prov->refcnt_lock);
 259
 260         /*
 261          * When the refcount drops below two, the store is the only
 262          * possible reference, or it has already been taken away from
 263          * the store (this may happen if a provider was activated
 264          * because it's a fallback, but isn't currently used)
 265          * When that happens, the provider is inactivated.
 266          */
 267         if (ref < 2 && prov->flag_initialized) {
 268             if (prov->teardown != NULL)
 269                 prov->teardown(prov->provctx);
 270             prov->flag_initialized = 0;
 271         }
 272
 273         /*
 274          * When the refcount drops to zero, it has been taken out of
 275          * the store.  All we have to do here is clean it out.
 276          */
 277         if (ref == 0) {
 278 #ifndef FIPS_MODE
 279             DSO_free(prov->module);
 280 #endif
 281             OPENSSL_free(prov->name);
 282             OPENSSL_free(prov->path);
 283             sk_INFOPAIR_pop_free(prov->parameters, free_infopair);
 284 #ifndef HAVE_ATOMICS
 285             CRYPTO_THREAD_lock_free(prov->refcnt_lock);
 286 #endif
 287             OPENSSL_free(prov);
 288         }
 289     }
 290 }
 291
 292 /* Setters */
 293 int ossl_provider_set_module_path(OSSL_PROVIDER *prov, const char *module_path)
 294 {
 295     OPENSSL_free(prov->path);
 296     if (module_path == NULL)
 297         return 1;
 298     if ((prov->path = OPENSSL_strdup(module_path)) != NULL)
 299         return 1;
 300     CRYPTOerr(CRYPTO_F_OSSL_PROVIDER_SET_MODULE_PATH, ERR_R_MALLOC_FAILURE);
 301     return 0;
 302 }
 303
 304 int ossl_provider_add_parameter(OSSL_PROVIDER *prov,
 305                                 const char *name, const char *value)
 306 {
 307     INFOPAIR *pair = NULL;
 308
 309     if ((pair = OPENSSL_zalloc(sizeof(*pair))) != NULL
 310         && (prov->parameters != NULL
 311             || (prov->parameters = sk_INFOPAIR_new_null()) != NULL)
 312         && (pair->name = OPENSSL_strdup(name)) != NULL
 313         && (pair->value = OPENSSL_strdup(value)) != NULL
 314         && sk_INFOPAIR_push(prov->parameters, pair) > 0)
 315         return 1;
 316
 317     if (pair != NULL) {
 318         OPENSSL_free(pair->name);
 319         OPENSSL_free(pair->value);
 320         OPENSSL_free(pair);
 321     }
 322     CRYPTOerr(CRYPTO_F_OSSL_PROVIDER_ADD_PARAMETER, ERR_R_MALLOC_FAILURE);
 323     return 0;
 324 }
 325
 326 /*
 327  * Provider activation.
 328  *
 329  * What "activation" means depends on the provider form; for built in
 330  * providers (in the library or the application alike), the provider
 331  * can already be considered to be loaded, all that's needed is to
 332  * initialize it.  However, for dynamically loadable provider modules,
 333  * we must first load that module.
 334  *
 335  * Built in modules are distinguished from dynamically loaded modules
 336  * with an already assigned init function.
 337  */
 338 static const OSSL_DISPATCH *core_dispatch; /* Define further down */
 339
 340 /*
 341  * Internal version that doesn't affect the store flags, and thereby avoid
 342  * locking.  Direct callers must remember to set the store flags when
 343  * appropriate
 344  */
 345 static int provider_activate(OSSL_PROVIDER *prov)
 346 {
 347     const OSSL_DISPATCH *provider_dispatch = NULL;
 348
 349     if (prov->flag_initialized)
 350         return 1;
 351
 352     /*
 353      * If the init function isn't set, it indicates that this provider is
 354      * a loadable module.
 355      */
 356     if (prov->init_function == NULL) {
 357 #ifdef FIPS_MODE
 358         return 0;
 359 #else
 360         if (prov->module == NULL) {
 361             char *allocated_path = NULL;
 362             const char *module_path = NULL;
 363             char *merged_path = NULL;
 364             const char *load_dir = ossl_safe_getenv("OPENSSL_MODULES");
 365
 366             if ((prov->module = DSO_new()) == NULL) {
 367                 /* DSO_new() generates an error already */
 368                 return 0;
 369             }
 370
 371             if (load_dir == NULL)
 372                 load_dir = MODULESDIR;
 373
 374             DSO_ctrl(prov->module, DSO_CTRL_SET_FLAGS,
 375                      DSO_FLAG_NAME_TRANSLATION_EXT_ONLY, NULL);
 376
 377             module_path = prov->path;
 378             if (module_path == NULL)
 379                 module_path = allocated_path =
 380                     DSO_convert_filename(prov->module, prov->name);
 381             if (module_path != NULL)
 382                 merged_path = DSO_merge(prov->module, module_path, load_dir);
 383
 384             if (merged_path == NULL
 385                 || (DSO_load(prov->module, merged_path, NULL, 0)) == NULL) {
 386                 DSO_free(prov->module);
 387                 prov->module = NULL;
 388             }
 389
 390             OPENSSL_free(merged_path);
 391             OPENSSL_free(allocated_path);
 392         }
 393
 394         if (prov->module != NULL)
 395             prov->init_function = (OSSL_provider_init_fn *)
 396                 DSO_bind_func(prov->module, "OSSL_provider_init");
 397 #endif
 398     }
 399
 400     if (prov->init_function == NULL
 401         || !prov->init_function(prov, core_dispatch, &provider_dispatch,
 402                                 &prov->provctx)) {
 403         CRYPTOerr(CRYPTO_F_PROVIDER_ACTIVATE, ERR_R_INIT_FAIL);
 404         ERR_add_error_data(2, "name=", prov->name);
 405 #ifndef FIPS_MODE
 406         DSO_free(prov->module);
 407         prov->module = NULL;
 408 #endif
 409         return 0;
 410     }
 411
 412     for (; provider_dispatch->function_id != 0; provider_dispatch++) {
 413         switch (provider_dispatch->function_id) {
 414         case OSSL_FUNC_PROVIDER_TEARDOWN:
 415             prov->teardown =
 416                 OSSL_get_provider_teardown(provider_dispatch);
 417             break;
 418         case OSSL_FUNC_PROVIDER_GET_PARAM_TYPES:
 419             prov->get_param_types =
 420                 OSSL_get_provider_get_param_types(provider_dispatch);
 421             break;
 422         case OSSL_FUNC_PROVIDER_GET_PARAMS:
 423             prov->get_params =
 424                 OSSL_get_provider_get_params(provider_dispatch);
 425             break;
 426         case OSSL_FUNC_PROVIDER_QUERY_OPERATION:
 427             prov->query_operation =
 428                 OSSL_get_provider_query_operation(provider_dispatch);
 429             break;
 430         }
 431     }
 432
 433     /* With this flag set, this provider has become fully "loaded". */
 434     prov->flag_initialized = 1;
 435
 436     return 1;
 437 }
 438
 439 int ossl_provider_activate(OSSL_PROVIDER *prov)
 440 {
 441     if (provider_activate(prov)) {
 442         CRYPTO_THREAD_write_lock(prov->store->lock);
 443         prov->store->use_fallbacks = 0;
 444         CRYPTO_THREAD_unlock(prov->store->lock);
 445         return 1;
 446     }
 447
 448     return 0;
 449 }
 450
 451 void *ossl_provider_ctx(const OSSL_PROVIDER *prov)
 452 {
 453     return prov->provctx;
 454 }
 455
 456
 457 static int provider_forall_loaded(struct provider_store_st *store,
 458                                   int *found_activated,
 459                                   int (*cb)(OSSL_PROVIDER *provider,
 460                                             void *cbdata),
 461                                   void *cbdata)
 462 {
 463     int i;
 464     int ret = 1;
 465     int num_provs = sk_OSSL_PROVIDER_num(store->providers);
 466
 467     if (found_activated != NULL)
 468         *found_activated = 0;
 469     for (i = 0; i < num_provs; i++) {
 470         OSSL_PROVIDER *prov =
 471             sk_OSSL_PROVIDER_value(store->providers, i);
 472
 473         if (prov->flag_initialized) {
 474             if (found_activated != NULL)
 475                 *found_activated = 1;
 476             if (!(ret = cb(prov, cbdata)))
 477                 break;
 478         }
 479     }
 480
 481     return ret;
 482 }
 483
 484 int ossl_provider_forall_loaded(OPENSSL_CTX *ctx,
 485                                 int (*cb)(OSSL_PROVIDER *provider,
 486                                           void *cbdata),
 487                                 void *cbdata)
 488 {
 489     int ret = 1;
 490     int i;
 491     struct provider_store_st *store = get_provider_store(ctx);
 492
 493     if (store != NULL) {
 494         int found_activated = 0;
 495
 496         CRYPTO_THREAD_read_lock(store->lock);
 497         ret = provider_forall_loaded(store, &found_activated, cb, cbdata);
 498
 499         /*
 500          * If there's nothing activated ever in this store, try to activate
 501          * all fallbacks.
 502          */
 503         if (!found_activated && store->use_fallbacks) {
 504             int num_provs = sk_OSSL_PROVIDER_num(store->providers);
 505             int activated_fallback_count = 0;
 506
 507             for (i = 0; i < num_provs; i++) {
 508                 OSSL_PROVIDER *prov =
 509                     sk_OSSL_PROVIDER_value(store->providers, i);
 510
 511                 /*
 512                  * Note that we don't care if the activation succeeds or
 513                  * not.  If it doesn't succeed, then the next loop will
 514                  * fail anyway.
 515                  */
 516                 if (prov->flag_fallback) {
 517                     activated_fallback_count++;
 518                     provider_activate(prov);
 519                 }
 520             }
 521
 522             if (activated_fallback_count > 0) {
 523                 /*
 524                  * We assume that all fallbacks have been added to the store
 525                  * before any fallback is activated.
 526                  * TODO: We may have to reconsider this, IF we find ourselves
 527                  * adding fallbacks after any previous fallback has been
 528                  * activated.
 529                  */
 530                 store->use_fallbacks = 0;
 531
 532                 /*
 533                  * Now that we've activated available fallbacks, try a
 534                  * second sweep
 535                  */
 536                 ret = provider_forall_loaded(store, NULL, cb, cbdata);
 537             }
 538         }
 539         CRYPTO_THREAD_unlock(store->lock);
 540     }
 541
 542     return ret;
 543 }
 544
 545 /* Setters of Provider Object data */
 546 int ossl_provider_set_fallback(OSSL_PROVIDER *prov)
 547 {
 548     if (prov == NULL)
 549         return 0;
 550
 551     prov->flag_fallback = 1;
 552     return 1;
 553 }
 554
 555 /* Getters of Provider Object data */
 556 const char *ossl_provider_name(OSSL_PROVIDER *prov)
 557 {
 558     return prov->name;
 559 }
 560
 561 const DSO *ossl_provider_dso(OSSL_PROVIDER *prov)
 562 {
 563     return prov->module;
 564 }
 565
 566 const char *ossl_provider_module_name(OSSL_PROVIDER *prov)
 567 {
 568 #ifdef FIPS_MODE
 569     return NULL;
 570 #else
 571     return DSO_get_filename(prov->module);
 572 #endif
 573 }
 574
 575 const char *ossl_provider_module_path(OSSL_PROVIDER *prov)
 576 {
 577 #ifdef FIPS_MODE
 578     return NULL;
 579 #else
 580     /* FIXME: Ensure it's a full path */
 581     return DSO_get_filename(prov->module);
 582 #endif
 583 }
 584
 585 /* Wrappers around calls to the provider */
 586 void ossl_provider_teardown(const OSSL_PROVIDER *prov)
 587 {
 588     if (prov->teardown != NULL)
 589         prov->teardown(prov->provctx);
 590 }
 591
 592 const OSSL_ITEM *ossl_provider_get_param_types(const OSSL_PROVIDER *prov)
 593 {
 594     return prov->get_param_types == NULL
 595         ? NULL : prov->get_param_types(prov->provctx);
 596 }
 597
 598 int ossl_provider_get_params(const OSSL_PROVIDER *prov,
 599                              const OSSL_PARAM params[])
 600 {
 601     return prov->get_params == NULL
 602         ? 0 : prov->get_params(prov->provctx, params);
 603 }
 604
 605
 606 const OSSL_ALGORITHM *ossl_provider_query_operation(const OSSL_PROVIDER *prov,
 607                                                     int operation_id,
 608                                                     int *no_cache)
 609 {
 610     return prov->query_operation(prov->provctx, operation_id, no_cache);
 611 }
 612
 613 /*-
 614  * Core functions for the provider
 615  * ===============================
 616  *
 617  * This is the set of functions that the core makes available to the provider
 618  */
 619
 620 /*
 621  * This returns a list of Provider Object parameters with their types, for
 622  * discovery.  We do not expect that many providers will use this, but one
 623  * never knows.
 624  */
 625 static const OSSL_ITEM param_types[] = {
 626     { OSSL_PARAM_UTF8_PTR, "openssl-version" },
 627     { OSSL_PARAM_UTF8_PTR, "provider-name" },
 628     { 0, NULL }
 629 };
 630
 631 static const OSSL_ITEM *core_get_param_types(const OSSL_PROVIDER *prov)
 632 {
 633     return param_types;
 634 }
 635
 636 static int core_get_params(const OSSL_PROVIDER *prov, const OSSL_PARAM params[])
 637 {
 638     int i;
 639     const OSSL_PARAM *p;
 640
 641     if ((p = OSSL_PARAM_locate(params, "openssl-version")) != NULL)
 642         OSSL_PARAM_set_utf8_ptr(p, OPENSSL_VERSION_STR);
 643     if ((p = OSSL_PARAM_locate(params, "provider-name")) != NULL)
 644         OSSL_PARAM_set_utf8_ptr(p, prov->name);
 645
 646     if (prov->parameters == NULL)
 647         return 1;
 648
 649     for (i = 0; i < sk_INFOPAIR_num(prov->parameters); i++) {
 650         INFOPAIR *pair = sk_INFOPAIR_value(prov->parameters, i);
 651
 652         if ((p = OSSL_PARAM_locate(params, pair->name)) != NULL)
 653             OSSL_PARAM_set_utf8_ptr(p, pair->value);
 654     }
 655
 656     return 1;
 657 }
 658
 659 static const OSSL_DISPATCH core_dispatch_[] = {
 660     { OSSL_FUNC_CORE_GET_PARAM_TYPES, (void (*)(void))core_get_param_types },
 661     { OSSL_FUNC_CORE_GET_PARAMS, (void (*)(void))core_get_params },
 662     { OSSL_FUNC_CORE_PUT_ERROR, (void (*)(void))ERR_put_error },
 663     { OSSL_FUNC_CORE_ADD_ERROR_VDATA, (void (*)(void))ERR_add_error_vdata },
 664     { 0, NULL }
 665 };
 666 static const OSSL_DISPATCH *core_dispatch = core_dispatch_;