crypto/evp/evp_rand.c

   1 /*
   2  * Copyright 2020-2021 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/evp.h>
  11
  12 #include <stdio.h>
  13 #include <stdlib.h>
  14 #include <openssl/engine.h>
  15 #include <openssl/evp.h>
  16 #include <openssl/x509v3.h>
  17 #include <openssl/rand.h>
  18 #include <openssl/core.h>
  19 #include <openssl/core_names.h>
  20 #include <openssl/crypto.h>
  21 #include "crypto/asn1.h"
  22 #include "crypto/evp.h"
  23 #include "internal/cryptlib.h"
  24 #include "internal/numbers.h"
  25 #include "internal/provider.h"
  26 #include "evp_local.h"
  27
  28 struct evp_rand_st {
  29     OSSL_PROVIDER *prov;
  30     int name_id;
  31     CRYPTO_REF_COUNT refcnt;
  32     CRYPTO_RWLOCK *refcnt_lock;
  33
  34     const OSSL_DISPATCH *dispatch;
  35     OSSL_FUNC_rand_newctx_fn *newctx;
  36     OSSL_FUNC_rand_freectx_fn *freectx;
  37     OSSL_FUNC_rand_instantiate_fn *instantiate;
  38     OSSL_FUNC_rand_uninstantiate_fn *uninstantiate;
  39     OSSL_FUNC_rand_generate_fn *generate;
  40     OSSL_FUNC_rand_reseed_fn *reseed;
  41     OSSL_FUNC_rand_nonce_fn *nonce;
  42     OSSL_FUNC_rand_enable_locking_fn *enable_locking;
  43     OSSL_FUNC_rand_lock_fn *lock;
  44     OSSL_FUNC_rand_unlock_fn *unlock;
  45     OSSL_FUNC_rand_gettable_params_fn *gettable_params;
  46     OSSL_FUNC_rand_gettable_ctx_params_fn *gettable_ctx_params;
  47     OSSL_FUNC_rand_settable_ctx_params_fn *settable_ctx_params;
  48     OSSL_FUNC_rand_get_params_fn *get_params;
  49     OSSL_FUNC_rand_get_ctx_params_fn *get_ctx_params;
  50     OSSL_FUNC_rand_set_ctx_params_fn *set_ctx_params;
  51     OSSL_FUNC_rand_verify_zeroization_fn *verify_zeroization;
  52 } /* EVP_RAND */ ;
  53
  54 static int evp_rand_up_ref(void *vrand)
  55 {
  56     EVP_RAND *rand = (EVP_RAND *)vrand;
  57     int ref = 0;
  58
  59     if (rand != NULL)
  60         return CRYPTO_UP_REF(&rand->refcnt, &ref, rand->refcnt_lock);
  61     return 1;
  62 }
  63
  64 static void evp_rand_free(void *vrand){
  65     EVP_RAND *rand = (EVP_RAND *)vrand;
  66     int ref = 0;
  67
  68     if (rand != NULL) {
  69         CRYPTO_DOWN_REF(&rand->refcnt, &ref, rand->refcnt_lock);
  70         if (ref <= 0) {
  71             ossl_provider_free(rand->prov);
  72             CRYPTO_THREAD_lock_free(rand->refcnt_lock);
  73             OPENSSL_free(rand);
  74         }
  75     }
  76 }
  77
  78 static void *evp_rand_new(void)
  79 {
  80     EVP_RAND *rand = OPENSSL_zalloc(sizeof(*rand));
  81
  82     if (rand == NULL
  83             || (rand->refcnt_lock = CRYPTO_THREAD_lock_new()) == NULL) {
  84         OPENSSL_free(rand);
  85         return NULL;
  86     }
  87     rand->refcnt = 1;
  88     return rand;
  89 }
  90
  91 /* Enable locking of the underlying DRBG/RAND if available */
  92 int EVP_RAND_enable_locking(EVP_RAND_CTX *rand)
  93 {
  94     if (rand->meth->enable_locking != NULL)
  95         return rand->meth->enable_locking(rand->data);
  96     ERR_raise(ERR_LIB_EVP, EVP_R_LOCKING_NOT_SUPPORTED);
  97     return 0;
  98 }
  99
 100 /* Lock the underlying DRBG/RAND if available */
 101 static int evp_rand_lock(EVP_RAND_CTX *rand)
 102 {
 103     if (rand->meth->lock != NULL)
 104         return rand->meth->lock(rand->data);
 105     return 1;
 106 }
 107
 108 /* Unlock the underlying DRBG/RAND if available */
 109 static void evp_rand_unlock(EVP_RAND_CTX *rand)
 110 {
 111     if (rand->meth->unlock != NULL)
 112         rand->meth->unlock(rand->data);
 113 }
 114
 115 static void *evp_rand_from_dispatch(int name_id,
 116                                     const OSSL_DISPATCH *fns,
 117                                     OSSL_PROVIDER *prov)
 118 {
 119     EVP_RAND *rand = NULL;
 120     int fnrandcnt = 0, fnctxcnt = 0, fnlockcnt = 0;
 121 #ifdef FIPS_MODULE
 122     int fnzeroizecnt = 0;
 123 #endif
 124
 125     if ((rand = evp_rand_new()) == NULL) {
 126         ERR_raise(ERR_LIB_EVP, ERR_R_MALLOC_FAILURE);
 127         return NULL;
 128     }
 129     rand->name_id = name_id;
 130     rand->dispatch = fns;
 131     for (; fns->function_id != 0; fns++) {
 132         switch (fns->function_id) {
 133         case OSSL_FUNC_RAND_NEWCTX:
 134             if (rand->newctx != NULL)
 135                 break;
 136             rand->newctx = OSSL_FUNC_rand_newctx(fns);
 137             fnctxcnt++;
 138             break;
 139         case OSSL_FUNC_RAND_FREECTX:
 140             if (rand->freectx != NULL)
 141                 break;
 142             rand->freectx = OSSL_FUNC_rand_freectx(fns);
 143             fnctxcnt++;
 144             break;
 145         case OSSL_FUNC_RAND_INSTANTIATE:
 146             if (rand->instantiate != NULL)
 147                 break;
 148             rand->instantiate = OSSL_FUNC_rand_instantiate(fns);
 149             fnrandcnt++;
 150             break;
 151         case OSSL_FUNC_RAND_UNINSTANTIATE:
 152              if (rand->uninstantiate != NULL)
 153                 break;
 154             rand->uninstantiate = OSSL_FUNC_rand_uninstantiate(fns);
 155             fnrandcnt++;
 156             break;
 157         case OSSL_FUNC_RAND_GENERATE:
 158             if (rand->generate != NULL)
 159                 break;
 160             rand->generate = OSSL_FUNC_rand_generate(fns);
 161             fnrandcnt++;
 162             break;
 163         case OSSL_FUNC_RAND_RESEED:
 164             if (rand->reseed != NULL)
 165                 break;
 166             rand->reseed = OSSL_FUNC_rand_reseed(fns);
 167             break;
 168         case OSSL_FUNC_RAND_NONCE:
 169             if (rand->nonce != NULL)
 170                 break;
 171             rand->nonce = OSSL_FUNC_rand_nonce(fns);
 172             break;
 173         case OSSL_FUNC_RAND_ENABLE_LOCKING:
 174             if (rand->enable_locking != NULL)
 175                 break;
 176             rand->enable_locking = OSSL_FUNC_rand_enable_locking(fns);
 177             fnlockcnt++;
 178             break;
 179         case OSSL_FUNC_RAND_LOCK:
 180             if (rand->lock != NULL)
 181                 break;
 182             rand->lock = OSSL_FUNC_rand_lock(fns);
 183             fnlockcnt++;
 184             break;
 185         case OSSL_FUNC_RAND_UNLOCK:
 186             if (rand->unlock != NULL)
 187                 break;
 188             rand->unlock = OSSL_FUNC_rand_unlock(fns);
 189             fnlockcnt++;
 190             break;
 191         case OSSL_FUNC_RAND_GETTABLE_PARAMS:
 192             if (rand->gettable_params != NULL)
 193                 break;
 194             rand->gettable_params =
 195                 OSSL_FUNC_rand_gettable_params(fns);
 196             break;
 197         case OSSL_FUNC_RAND_GETTABLE_CTX_PARAMS:
 198             if (rand->gettable_ctx_params != NULL)
 199                 break;
 200             rand->gettable_ctx_params =
 201                 OSSL_FUNC_rand_gettable_ctx_params(fns);
 202             break;
 203         case OSSL_FUNC_RAND_SETTABLE_CTX_PARAMS:
 204             if (rand->settable_ctx_params != NULL)
 205                 break;
 206             rand->settable_ctx_params =
 207                 OSSL_FUNC_rand_settable_ctx_params(fns);
 208             break;
 209         case OSSL_FUNC_RAND_GET_PARAMS:
 210             if (rand->get_params != NULL)
 211                 break;
 212             rand->get_params = OSSL_FUNC_rand_get_params(fns);
 213             break;
 214         case OSSL_FUNC_RAND_GET_CTX_PARAMS:
 215             if (rand->get_ctx_params != NULL)
 216                 break;
 217             rand->get_ctx_params = OSSL_FUNC_rand_get_ctx_params(fns);
 218             fnctxcnt++;
 219             break;
 220         case OSSL_FUNC_RAND_SET_CTX_PARAMS:
 221             if (rand->set_ctx_params != NULL)
 222                 break;
 223             rand->set_ctx_params = OSSL_FUNC_rand_set_ctx_params(fns);
 224             break;
 225         case OSSL_FUNC_RAND_VERIFY_ZEROIZATION:
 226             if (rand->verify_zeroization != NULL)
 227                 break;
 228             rand->verify_zeroization = OSSL_FUNC_rand_verify_zeroization(fns);
 229 #ifdef FIPS_MODULE
 230             fnzeroizecnt++;
 231 #endif
 232             break;
 233         }
 234     }
 235     /*
 236      * In order to be a consistent set of functions we must have at least
 237      * a complete set of "rand" functions and a complete set of context
 238      * management functions.  In FIPS mode, we also require the zeroization
 239      * verification function.
 240      *
 241      * In addition, if locking can be enabled, we need a complete set of
 242      * locking functions.
 243      */
 244     if (fnrandcnt != 3
 245             || fnctxcnt != 3
 246             || (fnlockcnt != 0 && fnlockcnt != 3)
 247 #ifdef FIPS_MODULE
 248             || fnzeroizecnt != 1
 249 #endif
 250        ) {
 251         evp_rand_free(rand);
 252         ERR_raise(ERR_LIB_EVP, EVP_R_INVALID_PROVIDER_FUNCTIONS);
 253         return NULL;
 254     }
 255
 256     if (prov != NULL && !ossl_provider_up_ref(prov)) {
 257         evp_rand_free(rand);
 258         ERR_raise(ERR_LIB_EVP, ERR_R_INTERNAL_ERROR);
 259         return NULL;
 260     }
 261     rand->prov = prov;
 262
 263     return rand;
 264 }
 265
 266 EVP_RAND *EVP_RAND_fetch(OSSL_LIB_CTX *libctx, const char *algorithm,
 267                          const char *properties)
 268 {
 269     return evp_generic_fetch(libctx, OSSL_OP_RAND, algorithm, properties,
 270                              evp_rand_from_dispatch, evp_rand_up_ref,
 271                              evp_rand_free);
 272 }
 273
 274 int EVP_RAND_up_ref(EVP_RAND *rand)
 275 {
 276     return evp_rand_up_ref(rand);
 277 }
 278
 279 void EVP_RAND_free(EVP_RAND *rand)
 280 {
 281     evp_rand_free(rand);
 282 }
 283
 284 int EVP_RAND_number(const EVP_RAND *rand)
 285 {
 286     return rand->name_id;
 287 }
 288
 289 const char *EVP_RAND_name(const EVP_RAND *rand)
 290 {
 291     return evp_first_name(rand->prov, rand->name_id);
 292 }
 293
 294 int EVP_RAND_is_a(const EVP_RAND *rand, const char *name)
 295 {
 296     return evp_is_a(rand->prov, rand->name_id, NULL, name);
 297 }
 298
 299 const OSSL_PROVIDER *EVP_RAND_provider(const EVP_RAND *rand)
 300 {
 301     return rand->prov;
 302 }
 303
 304 int EVP_RAND_get_params(EVP_RAND *rand, OSSL_PARAM params[])
 305 {
 306     if (rand->get_params != NULL)
 307         return rand->get_params(params);
 308     return 1;
 309 }
 310
 311 static int evp_rand_ctx_up_ref(EVP_RAND_CTX *ctx)
 312 {
 313     int ref = 0;
 314
 315     return CRYPTO_UP_REF(&ctx->refcnt, &ref, ctx->refcnt_lock);
 316 }
 317
 318 EVP_RAND_CTX *EVP_RAND_CTX_new(EVP_RAND *rand, EVP_RAND_CTX *parent)
 319 {
 320     EVP_RAND_CTX *ctx;
 321     void *parent_ctx = NULL;
 322     const OSSL_DISPATCH *parent_dispatch = NULL;
 323
 324     if (rand == NULL) {
 325         ERR_raise(ERR_LIB_EVP, EVP_R_INVALID_NULL_ALGORITHM);
 326         return NULL;
 327     }
 328
 329     ctx = OPENSSL_zalloc(sizeof(*ctx));
 330     if (ctx == NULL || (ctx->refcnt_lock = CRYPTO_THREAD_lock_new()) == NULL) {
 331         OPENSSL_free(ctx);
 332         ERR_raise(ERR_LIB_EVP, ERR_R_MALLOC_FAILURE);
 333         return NULL;
 334     }
 335     if (parent != NULL) {
 336         if (!evp_rand_ctx_up_ref(parent)) {
 337             ERR_raise(ERR_LIB_EVP, ERR_R_INTERNAL_ERROR);
 338             CRYPTO_THREAD_lock_free(ctx->refcnt_lock);
 339             OPENSSL_free(ctx);
 340             return NULL;
 341         }
 342         parent_ctx = parent->data;
 343         parent_dispatch = parent->meth->dispatch;
 344     }
 345     if ((ctx->data = rand->newctx(ossl_provider_ctx(rand->prov), parent_ctx,
 346                                   parent_dispatch)) == NULL
 347             || !EVP_RAND_up_ref(rand)) {
 348         ERR_raise(ERR_LIB_EVP, ERR_R_MALLOC_FAILURE);
 349         rand->freectx(ctx->data);
 350         CRYPTO_THREAD_lock_free(ctx->refcnt_lock);
 351         OPENSSL_free(ctx);
 352         EVP_RAND_CTX_free(parent);
 353         return NULL;
 354     }
 355     ctx->meth = rand;
 356     ctx->parent = parent;
 357     ctx->refcnt = 1;
 358     return ctx;
 359 }
 360
 361 void EVP_RAND_CTX_free(EVP_RAND_CTX *ctx)
 362 {
 363     if (ctx != NULL) {
 364         int ref = 0;
 365
 366         CRYPTO_DOWN_REF(&ctx->refcnt, &ref, ctx->refcnt_lock);
 367         if (ref <= 0) {
 368             EVP_RAND_CTX *parent = ctx->parent;
 369
 370             ctx->meth->freectx(ctx->data);
 371             ctx->data = NULL;
 372             EVP_RAND_free(ctx->meth);
 373             CRYPTO_THREAD_lock_free(ctx->refcnt_lock);
 374             OPENSSL_free(ctx);
 375             EVP_RAND_CTX_free(parent);
 376         }
 377     }
 378 }
 379
 380 EVP_RAND *EVP_RAND_CTX_rand(EVP_RAND_CTX *ctx)
 381 {
 382     return ctx->meth;
 383 }
 384
 385 static int evp_rand_get_ctx_params_locked(EVP_RAND_CTX *ctx,
 386                                           OSSL_PARAM params[])
 387 {
 388     return ctx->meth->get_ctx_params(ctx->data, params);
 389 }
 390
 391 int EVP_RAND_get_ctx_params(EVP_RAND_CTX *ctx, OSSL_PARAM params[])
 392 {
 393     int res;
 394
 395     if (!evp_rand_lock(ctx))
 396         return 0;
 397     res = evp_rand_get_ctx_params_locked(ctx, params);
 398     evp_rand_unlock(ctx);
 399     return res;
 400 }
 401
 402 static int evp_rand_set_ctx_params_locked(EVP_RAND_CTX *ctx,
 403                                           const OSSL_PARAM params[])
 404 {
 405     if (ctx->meth->set_ctx_params != NULL)
 406         return ctx->meth->set_ctx_params(ctx->data, params);
 407     return 1;
 408 }
 409
 410 int EVP_RAND_set_ctx_params(EVP_RAND_CTX *ctx, const OSSL_PARAM params[])
 411 {
 412     int res;
 413
 414     if (!evp_rand_lock(ctx))
 415         return 0;
 416     res = evp_rand_set_ctx_params_locked(ctx, params);
 417     evp_rand_unlock(ctx);
 418     return res;
 419 }
 420
 421 const OSSL_PARAM *EVP_RAND_gettable_params(const EVP_RAND *rand)
 422 {
 423     if (rand->gettable_params == NULL)
 424         return NULL;
 425     return rand->gettable_params(ossl_provider_ctx(EVP_RAND_provider(rand)));
 426 }
 427
 428 const OSSL_PARAM *EVP_RAND_gettable_ctx_params(const EVP_RAND *rand)
 429 {
 430     if (rand->gettable_ctx_params == NULL)
 431         return NULL;
 432     return rand->gettable_ctx_params(
 433                ossl_provider_ctx(EVP_RAND_provider(rand)));
 434 }
 435
 436 const OSSL_PARAM *EVP_RAND_settable_ctx_params(const EVP_RAND *rand)
 437 {
 438     if (rand->settable_ctx_params == NULL)
 439         return NULL;
 440     return rand->settable_ctx_params(
 441                ossl_provider_ctx(EVP_RAND_provider(rand)));
 442 }
 443
 444 void EVP_RAND_do_all_provided(OSSL_LIB_CTX *libctx,
 445                               void (*fn)(EVP_RAND *rand, void *arg),
 446                               void *arg)
 447 {
 448     evp_generic_do_all(libctx, OSSL_OP_RAND,
 449                        (void (*)(void *, void *))fn, arg,
 450                        evp_rand_from_dispatch, evp_rand_free);
 451 }
 452
 453 void EVP_RAND_names_do_all(const EVP_RAND *rand,
 454                            void (*fn)(const char *name, void *data),
 455                            void *data)
 456 {
 457     if (rand->prov != NULL)
 458         evp_names_do_all(rand->prov, rand->name_id, fn, data);
 459 }
 460
 461 static int evp_rand_instantiate_locked
 462     (EVP_RAND_CTX *ctx, unsigned int strength, int prediction_resistance,
 463      const unsigned char *pstr, size_t pstr_len)
 464 {
 465     return ctx->meth->instantiate(ctx->data, strength, prediction_resistance,
 466                                   pstr, pstr_len);
 467 }
 468
 469 int EVP_RAND_instantiate(EVP_RAND_CTX *ctx, unsigned int strength,
 470                          int prediction_resistance,
 471                          const unsigned char *pstr, size_t pstr_len)
 472 {
 473     int res;
 474
 475     if (!evp_rand_lock(ctx))
 476         return 0;
 477     res = evp_rand_instantiate_locked(ctx, strength, prediction_resistance,
 478                                       pstr, pstr_len);
 479     evp_rand_unlock(ctx);
 480     return res;
 481 }
 482
 483 static int evp_rand_uninstantiate_locked(EVP_RAND_CTX *ctx)
 484 {
 485     return ctx->meth->uninstantiate(ctx->data);
 486 }
 487
 488 int EVP_RAND_uninstantiate(EVP_RAND_CTX *ctx)
 489 {
 490     int res;
 491
 492     if (!evp_rand_lock(ctx))
 493         return 0;
 494     res = evp_rand_uninstantiate_locked(ctx);
 495     evp_rand_unlock(ctx);
 496     return res;
 497 }
 498
 499 static int evp_rand_generate_locked(EVP_RAND_CTX *ctx, unsigned char *out,
 500                                     size_t outlen, unsigned int strength,
 501                                     int prediction_resistance,
 502                                     const unsigned char *addin,
 503                                     size_t addin_len)
 504 {
 505     size_t chunk, max_request = 0;
 506     OSSL_PARAM params[2] = { OSSL_PARAM_END, OSSL_PARAM_END };
 507
 508     params[0] = OSSL_PARAM_construct_size_t(OSSL_RAND_PARAM_MAX_REQUEST,
 509                                             &max_request);
 510     if (!evp_rand_get_ctx_params_locked(ctx, params)
 511             || max_request == 0) {
 512         ERR_raise(ERR_LIB_EVP, EVP_R_UNABLE_TO_GET_MAXIMUM_REQUEST_SIZE);
 513         return 0;
 514     }
 515     for (; outlen > 0; outlen -= chunk, out += chunk) {
 516         chunk = outlen > max_request ? max_request : outlen;
 517         if (!ctx->meth->generate(ctx->data, out, chunk, strength,
 518                                  prediction_resistance, addin, addin_len)) {
 519             ERR_raise(ERR_LIB_EVP, EVP_R_GENERATE_ERROR);
 520             return 0;
 521         }
 522         /*
 523          * Prediction resistance is only relevant the first time around,
 524          * subsequently, the DRBG has already been properly reseeded.
 525          */
 526         prediction_resistance = 0;
 527     }
 528     return 1;
 529 }
 530
 531 int EVP_RAND_generate(EVP_RAND_CTX *ctx, unsigned char *out, size_t outlen,
 532                       unsigned int strength, int prediction_resistance,
 533                       const unsigned char *addin, size_t addin_len)
 534 {
 535     int res;
 536
 537     if (!evp_rand_lock(ctx))
 538         return 0;
 539     res = evp_rand_generate_locked(ctx, out, outlen, strength,
 540                                    prediction_resistance, addin, addin_len);
 541     evp_rand_unlock(ctx);
 542     return res;
 543 }
 544
 545 static int evp_rand_reseed_locked(EVP_RAND_CTX *ctx, int prediction_resistance,
 546                                   const unsigned char *ent, size_t ent_len,
 547                                   const unsigned char *addin, size_t addin_len)
 548 {
 549     if (ctx->meth->reseed != NULL)
 550         return ctx->meth->reseed(ctx->data, prediction_resistance,
 551                                  ent, ent_len, addin, addin_len);
 552     return 1;
 553 }
 554
 555 int EVP_RAND_reseed(EVP_RAND_CTX *ctx, int prediction_resistance,
 556                     const unsigned char *ent, size_t ent_len,
 557                     const unsigned char *addin, size_t addin_len)
 558 {
 559     int res;
 560
 561     if (!evp_rand_lock(ctx))
 562         return 0;
 563     res = evp_rand_reseed_locked(ctx, prediction_resistance,
 564                                  ent, ent_len, addin, addin_len);
 565     evp_rand_unlock(ctx);
 566     return res;
 567 }
 568
 569 static unsigned int evp_rand_strength_locked(EVP_RAND_CTX *ctx)
 570 {
 571     OSSL_PARAM params[2] = { OSSL_PARAM_END, OSSL_PARAM_END };
 572     unsigned int strength = 0;
 573
 574     params[0] = OSSL_PARAM_construct_uint(OSSL_RAND_PARAM_STRENGTH, &strength);
 575     if (!evp_rand_get_ctx_params_locked(ctx, params))
 576         return 0;
 577     return strength;
 578 }
 579
 580 unsigned int EVP_RAND_strength(EVP_RAND_CTX *ctx)
 581 {
 582     unsigned int res;
 583
 584     if (!evp_rand_lock(ctx))
 585         return 0;
 586     res = evp_rand_strength_locked(ctx);
 587     evp_rand_unlock(ctx);
 588     return res;
 589 }
 590
 591 static int evp_rand_nonce_locked(EVP_RAND_CTX *ctx, unsigned char *out,
 592                                  size_t outlen)
 593 {
 594     unsigned int str = evp_rand_strength_locked(ctx);
 595
 596     if (ctx->meth->nonce == NULL)
 597         return 0;
 598     if (ctx->meth->nonce(ctx->data, out, str, outlen, outlen))
 599         return 1;
 600     return evp_rand_generate_locked(ctx, out, outlen, str, 0, NULL, 0);
 601 }
 602
 603 int EVP_RAND_nonce(EVP_RAND_CTX *ctx, unsigned char *out, size_t outlen)
 604 {
 605     int res;
 606
 607     if (!evp_rand_lock(ctx))
 608         return 0;
 609     res = evp_rand_nonce_locked(ctx, out, outlen);
 610     evp_rand_unlock(ctx);
 611     return res;
 612 }
 613
 614 int EVP_RAND_state(EVP_RAND_CTX *ctx)
 615 {
 616     OSSL_PARAM params[2] = { OSSL_PARAM_END, OSSL_PARAM_END };
 617     int state;
 618
 619     params[0] = OSSL_PARAM_construct_int(OSSL_RAND_PARAM_STATE, &state);
 620     if (!EVP_RAND_get_ctx_params(ctx, params))
 621         state = EVP_RAND_STATE_ERROR;
 622     return state;
 623 }
 624
 625 static int evp_rand_verify_zeroization_locked(EVP_RAND_CTX *ctx)
 626 {
 627     if (ctx->meth->verify_zeroization != NULL)
 628         return ctx->meth->verify_zeroization(ctx->data);
 629     return 0;
 630 }
 631
 632 int EVP_RAND_verify_zeroization(EVP_RAND_CTX *ctx)
 633 {
 634     int res;
 635
 636     if (!evp_rand_lock(ctx))
 637         return 0;
 638     res = evp_rand_verify_zeroization_locked(ctx);
 639     evp_rand_unlock(ctx);
 640     return res;
 641 }