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             DSO_free(prov->module);
 279             OPENSSL_free(prov->name);
 280             OPENSSL_free(prov->path);
 281             sk_INFOPAIR_pop_free(prov->parameters, free_infopair);
 282 #ifndef HAVE_ATOMICS
 283             CRYPTO_THREAD_lock_free(prov->refcnt_lock);
 284 #endif
 285             OPENSSL_free(prov);
 286         }
 287     }
 288 }
 289
 290 /* Setters */
 291 int ossl_provider_set_module_path(OSSL_PROVIDER *prov, const char *module_path)
 292 {
 293     OPENSSL_free(prov->path);
 294     if (module_path == NULL)
 295         return 1;
 296     if ((prov->path = OPENSSL_strdup(module_path)) != NULL)
 297         return 1;
 298     CRYPTOerr(CRYPTO_F_OSSL_PROVIDER_SET_MODULE_PATH, ERR_R_MALLOC_FAILURE);
 299     return 0;
 300 }
 301
 302 int ossl_provider_add_parameter(OSSL_PROVIDER *prov,
 303                                 const char *name, const char *value)
 304 {
 305     INFOPAIR *pair = NULL;
 306
 307     if ((pair = OPENSSL_zalloc(sizeof(*pair))) != NULL
 308         && (prov->parameters != NULL
 309             || (prov->parameters = sk_INFOPAIR_new_null()) != NULL)
 310         && (pair->name = OPENSSL_strdup(name)) != NULL
 311         && (pair->value = OPENSSL_strdup(value)) != NULL
 312         && sk_INFOPAIR_push(prov->parameters, pair) > 0)
 313         return 1;
 314
 315     if (pair != NULL) {
 316         OPENSSL_free(pair->name);
 317         OPENSSL_free(pair->value);
 318         OPENSSL_free(pair);
 319     }
 320     CRYPTOerr(CRYPTO_F_OSSL_PROVIDER_ADD_PARAMETER, ERR_R_MALLOC_FAILURE);
 321     return 0;
 322 }
 323
 324 /*
 325  * Provider activation.
 326  *
 327  * What "activation" means depends on the provider form; for built in
 328  * providers (in the library or the application alike), the provider
 329  * can already be considered to be loaded, all that's needed is to
 330  * initialize it.  However, for dynamically loadable provider modules,
 331  * we must first load that module.
 332  *
 333  * Built in modules are distinguished from dynamically loaded modules
 334  * with an already assigned init function.
 335  */
 336 static const OSSL_DISPATCH *core_dispatch; /* Define further down */
 337
 338 /*
 339  * Internal version that doesn't affect the store flags, and thereby avoid
 340  * locking.  Direct callers must remember to set the store flags when
 341  * appropriate
 342  */
 343 static int provider_activate(OSSL_PROVIDER *prov)
 344 {
 345     const OSSL_DISPATCH *provider_dispatch = NULL;
 346
 347     if (prov->flag_initialized)
 348         return 1;
 349
 350     /*
 351      * If the init function isn't set, it indicates that this provider is
 352      * a loadable module.
 353      */
 354     if (prov->init_function == NULL) {
 355         if (prov->module == NULL) {
 356             char *allocated_path = NULL;
 357             const char *module_path = NULL;
 358             char *merged_path = NULL;
 359             const char *load_dir = ossl_safe_getenv("OPENSSL_MODULES");
 360
 361             if ((prov->module = DSO_new()) == NULL) {
 362                 /* DSO_new() generates an error already */
 363                 return 0;
 364             }
 365
 366             if (load_dir == NULL)
 367                 load_dir = MODULESDIR;
 368
 369             DSO_ctrl(prov->module, DSO_CTRL_SET_FLAGS,
 370                      DSO_FLAG_NAME_TRANSLATION_EXT_ONLY, NULL);
 371
 372             module_path = prov->path;
 373             if (module_path == NULL)
 374                 module_path = allocated_path =
 375                     DSO_convert_filename(prov->module, prov->name);
 376             if (module_path != NULL)
 377                 merged_path = DSO_merge(prov->module, module_path, load_dir);
 378
 379             if (merged_path == NULL
 380                 || (DSO_load(prov->module, merged_path, NULL, 0)) == NULL) {
 381                 DSO_free(prov->module);
 382                 prov->module = NULL;
 383             }
 384
 385             OPENSSL_free(merged_path);
 386             OPENSSL_free(allocated_path);
 387         }
 388
 389         if (prov->module != NULL)
 390             prov->init_function = (OSSL_provider_init_fn *)
 391                 DSO_bind_func(prov->module, "OSSL_provider_init");
 392     }
 393
 394     if (prov->init_function == NULL
 395         || !prov->init_function(prov, core_dispatch, &provider_dispatch,
 396                                 &prov->provctx)) {
 397         CRYPTOerr(CRYPTO_F_PROVIDER_ACTIVATE, ERR_R_INIT_FAIL);
 398         ERR_add_error_data(2, "name=", prov->name);
 399         DSO_free(prov->module);
 400         prov->module = NULL;
 401         return 0;
 402     }
 403
 404     for (; provider_dispatch->function_id != 0; provider_dispatch++) {
 405         switch (provider_dispatch->function_id) {
 406         case OSSL_FUNC_PROVIDER_TEARDOWN:
 407             prov->teardown =
 408                 OSSL_get_provider_teardown(provider_dispatch);
 409             break;
 410         case OSSL_FUNC_PROVIDER_GET_PARAM_TYPES:
 411             prov->get_param_types =
 412                 OSSL_get_provider_get_param_types(provider_dispatch);
 413             break;
 414         case OSSL_FUNC_PROVIDER_GET_PARAMS:
 415             prov->get_params =
 416                 OSSL_get_provider_get_params(provider_dispatch);
 417             break;
 418         case OSSL_FUNC_PROVIDER_QUERY_OPERATION:
 419             prov->query_operation =
 420                 OSSL_get_provider_query_operation(provider_dispatch);
 421             break;
 422         }
 423     }
 424
 425     /* With this flag set, this provider has become fully "loaded". */
 426     prov->flag_initialized = 1;
 427
 428     return 1;
 429 }
 430
 431 int ossl_provider_activate(OSSL_PROVIDER *prov)
 432 {
 433     if (provider_activate(prov)) {
 434         CRYPTO_THREAD_write_lock(prov->store->lock);
 435         prov->store->use_fallbacks = 0;
 436         CRYPTO_THREAD_unlock(prov->store->lock);
 437         return 1;
 438     }
 439
 440     return 0;
 441 }
 442
 443 void *ossl_provider_ctx(const OSSL_PROVIDER *prov)
 444 {
 445     return prov->provctx;
 446 }
 447
 448
 449 static int provider_forall_loaded(struct provider_store_st *store,
 450                                   int *found_activated,
 451                                   int (*cb)(OSSL_PROVIDER *provider,
 452                                             void *cbdata),
 453                                   void *cbdata)
 454 {
 455     int i;
 456     int ret = 1;
 457     int num_provs = sk_OSSL_PROVIDER_num(store->providers);
 458
 459     if (found_activated != NULL)
 460         *found_activated = 0;
 461     for (i = 0; i < num_provs; i++) {
 462         OSSL_PROVIDER *prov =
 463             sk_OSSL_PROVIDER_value(store->providers, i);
 464
 465         if (prov->flag_initialized) {
 466             if (found_activated != NULL)
 467                 *found_activated = 1;
 468             if (!(ret = cb(prov, cbdata)))
 469                 break;
 470         }
 471     }
 472
 473     return ret;
 474 }
 475
 476 int ossl_provider_forall_loaded(OPENSSL_CTX *ctx,
 477                                 int (*cb)(OSSL_PROVIDER *provider,
 478                                           void *cbdata),
 479                                 void *cbdata)
 480 {
 481     int ret = 1;
 482     int i;
 483     struct provider_store_st *store = get_provider_store(ctx);
 484
 485     if (store != NULL) {
 486         int found_activated = 0;
 487
 488         CRYPTO_THREAD_read_lock(store->lock);
 489         ret = provider_forall_loaded(store, &found_activated, cb, cbdata);
 490
 491         /*
 492          * If there's nothing activated ever in this store, try to activate
 493          * all fallbacks.
 494          */
 495         if (!found_activated && store->use_fallbacks) {
 496             int num_provs = sk_OSSL_PROVIDER_num(store->providers);
 497             int activated_fallback_count = 0;
 498
 499             for (i = 0; i < num_provs; i++) {
 500                 OSSL_PROVIDER *prov =
 501                     sk_OSSL_PROVIDER_value(store->providers, i);
 502
 503                 /*
 504                  * Note that we don't care if the activation succeeds or
 505                  * not.  If it doesn't succeed, then the next loop will
 506                  * fail anyway.
 507                  */
 508                 if (prov->flag_fallback) {
 509                     activated_fallback_count++;
 510                     provider_activate(prov);
 511                 }
 512             }
 513
 514             if (activated_fallback_count > 0) {
 515                 /*
 516                  * We assume that all fallbacks have been added to the store
 517                  * before any fallback is activated.
 518                  * TODO: We may have to reconsider this, IF we find ourselves
 519                  * adding fallbacks after any previous fallback has been
 520                  * activated.
 521                  */
 522                 store->use_fallbacks = 0;
 523
 524                 /*
 525                  * Now that we've activated available fallbacks, try a
 526                  * second sweep
 527                  */
 528                 ret = provider_forall_loaded(store, NULL, cb, cbdata);
 529             }
 530         }
 531         CRYPTO_THREAD_unlock(store->lock);
 532     }
 533
 534     return ret;
 535 }
 536
 537 /* Setters of Provider Object data */
 538 int ossl_provider_set_fallback(OSSL_PROVIDER *prov)
 539 {
 540     if (prov == NULL)
 541         return 0;
 542
 543     prov->flag_fallback = 1;
 544     return 1;
 545 }
 546
 547 /* Getters of Provider Object data */
 548 const char *ossl_provider_name(OSSL_PROVIDER *prov)
 549 {
 550     return prov->name;
 551 }
 552
 553 const DSO *ossl_provider_dso(OSSL_PROVIDER *prov)
 554 {
 555     return prov->module;
 556 }
 557
 558 const char *ossl_provider_module_name(OSSL_PROVIDER *prov)
 559 {
 560     return DSO_get_filename(prov->module);
 561 }
 562
 563 const char *ossl_provider_module_path(OSSL_PROVIDER *prov)
 564 {
 565     /* FIXME: Ensure it's a full path */
 566     return DSO_get_filename(prov->module);
 567 }
 568
 569 /* Wrappers around calls to the provider */
 570 void ossl_provider_teardown(const OSSL_PROVIDER *prov)
 571 {
 572     if (prov->teardown != NULL)
 573         prov->teardown(prov->provctx);
 574 }
 575
 576 const OSSL_ITEM *ossl_provider_get_param_types(const OSSL_PROVIDER *prov)
 577 {
 578     return prov->get_param_types == NULL
 579         ? NULL : prov->get_param_types(prov->provctx);
 580 }
 581
 582 int ossl_provider_get_params(const OSSL_PROVIDER *prov,
 583                              const OSSL_PARAM params[])
 584 {
 585     return prov->get_params == NULL
 586         ? 0 : prov->get_params(prov->provctx, params);
 587 }
 588
 589
 590 const OSSL_ALGORITHM *ossl_provider_query_operation(const OSSL_PROVIDER *prov,
 591                                                     int operation_id,
 592                                                     int *no_cache)
 593 {
 594     return prov->query_operation(prov->provctx, operation_id, no_cache);
 595 }
 596
 597 /*-
 598  * Core functions for the provider
 599  * ===============================
 600  *
 601  * This is the set of functions that the core makes available to the provider
 602  */
 603
 604 /*
 605  * This returns a list of Provider Object parameters with their types, for
 606  * discovery.  We do not expect that many providers will use this, but one
 607  * never knows.
 608  */
 609 static const OSSL_ITEM param_types[] = {
 610     { OSSL_PARAM_UTF8_PTR, "openssl-version" },
 611     { OSSL_PARAM_UTF8_PTR, "provider-name" },
 612     { 0, NULL }
 613 };
 614
 615 static const OSSL_ITEM *core_get_param_types(const OSSL_PROVIDER *prov)
 616 {
 617     return param_types;
 618 }
 619
 620 static int core_get_params(const OSSL_PROVIDER *prov, const OSSL_PARAM params[])
 621 {
 622     int i;
 623     const OSSL_PARAM *p;
 624
 625     if ((p = OSSL_PARAM_locate(params, "openssl-version")) != NULL)
 626         OSSL_PARAM_set_utf8_ptr(p, OPENSSL_VERSION_STR);
 627     if ((p = OSSL_PARAM_locate(params, "provider-name")) != NULL)
 628         OSSL_PARAM_set_utf8_ptr(p, prov->name);
 629
 630     if (prov->parameters == NULL)
 631         return 1;
 632
 633     for (i = 0; i < sk_INFOPAIR_num(prov->parameters); i++) {
 634         INFOPAIR *pair = sk_INFOPAIR_value(prov->parameters, i);
 635
 636         if ((p = OSSL_PARAM_locate(params, pair->name)) != NULL)
 637             OSSL_PARAM_set_utf8_ptr(p, pair->value);
 638     }
 639
 640     return 1;
 641 }
 642
 643 static const OSSL_DISPATCH core_dispatch_[] = {
 644     { OSSL_FUNC_CORE_GET_PARAM_TYPES, (void (*)(void))core_get_param_types },
 645     { OSSL_FUNC_CORE_GET_PARAMS, (void (*)(void))core_get_params },
 646     { 0, NULL }
 647 };
 648 static const OSSL_DISPATCH *core_dispatch = core_dispatch_;