crypto/evp/digest.c

   1 /*
   2  * Copyright 1995-2019 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 <stdio.h>
  11 #include <openssl/objects.h>
  12 #include <openssl/evp.h>
  13 #include <openssl/engine.h>
  14 #include <openssl/params.h>
  15 #include <openssl/core_names.h>
  16 #include "internal/cryptlib.h"
  17 #include "crypto/evp.h"
  18 #include "internal/provider.h"
  19 #include "evp_locl.h"
  20
  21 /* This call frees resources associated with the context */
  22 int EVP_MD_CTX_reset(EVP_MD_CTX *ctx)
  23 {
  24     if (ctx == NULL)
  25         return 1;
  26
  27     if (ctx->digest == NULL || ctx->digest->prov == NULL)
  28         goto legacy;
  29
  30     if (ctx->provctx != NULL) {
  31         if (ctx->digest->freectx != NULL)
  32             ctx->digest->freectx(ctx->provctx);
  33         ctx->provctx = NULL;
  34         EVP_MD_CTX_set_flags(ctx, EVP_MD_CTX_FLAG_CLEANED);
  35     }
  36
  37     if (ctx->pctx != NULL)
  38         goto legacy;
  39
  40     return 1;
  41
  42     /* TODO(3.0): Remove legacy code below */
  43  legacy:
  44
  45     /*
  46      * Don't assume ctx->md_data was cleaned in EVP_Digest_Final, because
  47      * sometimes only copies of the context are ever finalised.
  48      */
  49     if (ctx->digest && ctx->digest->cleanup
  50         && !EVP_MD_CTX_test_flags(ctx, EVP_MD_CTX_FLAG_CLEANED))
  51         ctx->digest->cleanup(ctx);
  52     if (ctx->digest && ctx->digest->ctx_size && ctx->md_data
  53         && !EVP_MD_CTX_test_flags(ctx, EVP_MD_CTX_FLAG_REUSE)) {
  54         OPENSSL_clear_free(ctx->md_data, ctx->digest->ctx_size);
  55     }
  56     /*
  57      * pctx should be freed by the user of EVP_MD_CTX
  58      * if EVP_MD_CTX_FLAG_KEEP_PKEY_CTX is set
  59      */
  60 #ifndef FIPS_MODE
  61     /* TODO(3.0): Temporarily no support for EVP_DigestSign* in FIPS module */
  62     if (!EVP_MD_CTX_test_flags(ctx, EVP_MD_CTX_FLAG_KEEP_PKEY_CTX))
  63         EVP_PKEY_CTX_free(ctx->pctx);
  64
  65 # ifndef OPENSSL_NO_ENGINE
  66     ENGINE_finish(ctx->engine);
  67 # endif
  68 #endif
  69     OPENSSL_cleanse(ctx, sizeof(*ctx));
  70
  71     return 1;
  72 }
  73
  74 EVP_MD_CTX *EVP_MD_CTX_new(void)
  75 {
  76     return OPENSSL_zalloc(sizeof(EVP_MD_CTX));
  77 }
  78
  79 void EVP_MD_CTX_free(EVP_MD_CTX *ctx)
  80 {
  81     if (ctx == NULL)
  82         return;
  83
  84     if (ctx->digest == NULL || ctx->digest->prov == NULL)
  85         goto legacy;
  86
  87     EVP_MD_CTX_reset(ctx);
  88
  89     EVP_MD_free(ctx->fetched_digest);
  90     ctx->fetched_digest = NULL;
  91     ctx->digest = NULL;
  92     ctx->reqdigest = NULL;
  93
  94     OPENSSL_free(ctx);
  95     return;
  96
  97     /* TODO(3.0): Remove legacy code below */
  98  legacy:
  99     EVP_MD_CTX_reset(ctx);
 100     OPENSSL_free(ctx);
 101 }
 102
 103 int EVP_DigestInit(EVP_MD_CTX *ctx, const EVP_MD *type)
 104 {
 105     EVP_MD_CTX_reset(ctx);
 106     return EVP_DigestInit_ex(ctx, type, NULL);
 107 }
 108
 109 int EVP_DigestInit_ex(EVP_MD_CTX *ctx, const EVP_MD *type, ENGINE *impl)
 110 {
 111 #if !defined(OPENSSL_NO_ENGINE) && !defined(FIPS_MODE)
 112     ENGINE *tmpimpl = NULL;
 113 #endif
 114
 115     EVP_MD_CTX_clear_flags(ctx, EVP_MD_CTX_FLAG_CLEANED);
 116
 117     if (type != NULL)
 118         ctx->reqdigest = type;
 119
 120     /* TODO(3.0): Legacy work around code below. Remove this */
 121 #if !defined(OPENSSL_NO_ENGINE) && !defined(FIPS_MODE)
 122     /*
 123      * Whether it's nice or not, "Inits" can be used on "Final"'d contexts so
 124      * this context may already have an ENGINE! Try to avoid releasing the
 125      * previous handle, re-querying for an ENGINE, and having a
 126      * reinitialisation, when it may all be unnecessary.
 127      */
 128     if (ctx->engine && ctx->digest &&
 129         (type == NULL || (type->type == ctx->digest->type)))
 130         goto skip_to_init;
 131
 132     if (type != NULL) {
 133         /*
 134          * Ensure an ENGINE left lying around from last time is cleared (the
 135          * previous check attempted to avoid this if the same ENGINE and
 136          * EVP_MD could be used).
 137          */
 138         ENGINE_finish(ctx->engine);
 139         ctx->engine = NULL;
 140     }
 141
 142     if (type != NULL && impl == NULL)
 143         tmpimpl = ENGINE_get_digest_engine(type->type);
 144 #endif
 145
 146     /*
 147      * If there are engines involved or if we're being used as part of
 148      * EVP_DigestSignInit then we should use legacy handling for now.
 149      */
 150     if (ctx->engine != NULL
 151             || impl != NULL
 152 #if !defined(OPENSSL_NO_ENGINE) && !defined(FIPS_MODE)
 153             || tmpimpl != NULL
 154 #endif
 155             || ctx->pctx != NULL
 156             || (ctx->flags & EVP_MD_CTX_FLAG_NO_INIT) != 0) {
 157         if (ctx->digest == ctx->fetched_digest)
 158             ctx->digest = NULL;
 159         EVP_MD_free(ctx->fetched_digest);
 160         ctx->fetched_digest = NULL;
 161         goto legacy;
 162     }
 163
 164     if (ctx->digest != NULL && ctx->digest->ctx_size > 0) {
 165         OPENSSL_clear_free(ctx->md_data, ctx->digest->ctx_size);
 166         ctx->md_data = NULL;
 167     }
 168
 169     /* TODO(3.0): Start of non-legacy code below */
 170
 171     if (type->prov == NULL) {
 172 #ifdef FIPS_MODE
 173         /* We only do explict fetches inside the FIPS module */
 174         EVPerr(EVP_F_EVP_DIGESTINIT_EX, EVP_R_INITIALIZATION_ERROR);
 175         return 0;
 176 #else
 177         EVP_MD *provmd = EVP_MD_fetch(NULL, OBJ_nid2sn(type->type), "");
 178
 179         if (provmd == NULL) {
 180             EVPerr(EVP_F_EVP_DIGESTINIT_EX, EVP_R_INITIALIZATION_ERROR);
 181             return 0;
 182         }
 183         type = provmd;
 184         EVP_MD_free(ctx->fetched_digest);
 185         ctx->fetched_digest = provmd;
 186 #endif
 187     }
 188
 189     if (ctx->provctx != NULL && ctx->digest != NULL && ctx->digest != type) {
 190         if (ctx->digest->freectx != NULL)
 191             ctx->digest->freectx(ctx->provctx);
 192         ctx->provctx = NULL;
 193     }
 194     ctx->digest = type;
 195     if (ctx->provctx == NULL) {
 196         ctx->provctx = ctx->digest->newctx(ossl_provider_ctx(type->prov));
 197         if (ctx->provctx == NULL) {
 198             EVPerr(EVP_F_EVP_DIGESTINIT_EX, EVP_R_INITIALIZATION_ERROR);
 199             return 0;
 200         }
 201     }
 202
 203     if (ctx->digest->dinit == NULL) {
 204         EVPerr(EVP_F_EVP_DIGESTINIT_EX, EVP_R_INITIALIZATION_ERROR);
 205         return 0;
 206     }
 207
 208     return ctx->digest->dinit(ctx->provctx);
 209
 210     /* TODO(3.0): Remove legacy code below */
 211  legacy:
 212
 213 #if !defined(OPENSSL_NO_ENGINE) && !defined(FIPS_MODE)
 214     if (type) {
 215         if (impl != NULL) {
 216             if (!ENGINE_init(impl)) {
 217                 EVPerr(EVP_F_EVP_DIGESTINIT_EX, EVP_R_INITIALIZATION_ERROR);
 218                 return 0;
 219             }
 220         } else {
 221             /* Ask if an ENGINE is reserved for this job */
 222             impl = tmpimpl;
 223         }
 224         if (impl != NULL) {
 225             /* There's an ENGINE for this job ... (apparently) */
 226             const EVP_MD *d = ENGINE_get_digest(impl, type->type);
 227
 228             if (d == NULL) {
 229                 EVPerr(EVP_F_EVP_DIGESTINIT_EX, EVP_R_INITIALIZATION_ERROR);
 230                 ENGINE_finish(impl);
 231                 return 0;
 232             }
 233             /* We'll use the ENGINE's private digest definition */
 234             type = d;
 235             /*
 236              * Store the ENGINE functional reference so we know 'type' came
 237              * from an ENGINE and we need to release it when done.
 238              */
 239             ctx->engine = impl;
 240         } else
 241             ctx->engine = NULL;
 242     } else {
 243         if (!ctx->digest) {
 244             EVPerr(EVP_F_EVP_DIGESTINIT_EX, EVP_R_NO_DIGEST_SET);
 245             return 0;
 246         }
 247         type = ctx->digest;
 248     }
 249 #endif
 250     if (ctx->digest != type) {
 251         if (ctx->digest && ctx->digest->ctx_size) {
 252             OPENSSL_clear_free(ctx->md_data, ctx->digest->ctx_size);
 253             ctx->md_data = NULL;
 254         }
 255         ctx->digest = type;
 256         if (!(ctx->flags & EVP_MD_CTX_FLAG_NO_INIT) && type->ctx_size) {
 257             ctx->update = type->update;
 258             ctx->md_data = OPENSSL_zalloc(type->ctx_size);
 259             if (ctx->md_data == NULL) {
 260                 EVPerr(EVP_F_EVP_DIGESTINIT_EX, ERR_R_MALLOC_FAILURE);
 261                 return 0;
 262             }
 263         }
 264     }
 265 #if !defined(OPENSSL_NO_ENGINE) && !defined(FIPS_MODE)
 266  skip_to_init:
 267 #endif
 268 #ifndef FIPS_MODE
 269     /*
 270      * TODO(3.0): Temporarily no support for EVP_DigestSign* inside FIPS module
 271      * or when using providers.
 272      */
 273     if (ctx->pctx != NULL
 274             && (!EVP_PKEY_CTX_IS_SIGNATURE_OP(ctx->pctx)
 275                  || ctx->pctx->op.sig.signature == NULL)) {
 276         int r;
 277         r = EVP_PKEY_CTX_ctrl(ctx->pctx, -1, EVP_PKEY_OP_TYPE_SIG,
 278                               EVP_PKEY_CTRL_DIGESTINIT, 0, ctx);
 279         if (r <= 0 && (r != -2))
 280             return 0;
 281     }
 282 #endif
 283     if (ctx->flags & EVP_MD_CTX_FLAG_NO_INIT)
 284         return 1;
 285     return ctx->digest->init(ctx);
 286 }
 287
 288 int EVP_DigestUpdate(EVP_MD_CTX *ctx, const void *data, size_t count)
 289 {
 290     if (count == 0)
 291         return 1;
 292
 293     if (ctx->digest == NULL || ctx->digest->prov == NULL)
 294         goto legacy;
 295
 296     if (ctx->digest->dupdate == NULL) {
 297         EVPerr(EVP_F_EVP_DIGESTUPDATE, EVP_R_UPDATE_ERROR);
 298         return 0;
 299     }
 300     return ctx->digest->dupdate(ctx->provctx, data, count);
 301
 302     /* TODO(3.0): Remove legacy code below */
 303  legacy:
 304     return ctx->update(ctx, data, count);
 305 }
 306
 307 /* The caller can assume that this removes any secret data from the context */
 308 int EVP_DigestFinal(EVP_MD_CTX *ctx, unsigned char *md, unsigned int *size)
 309 {
 310     int ret;
 311     ret = EVP_DigestFinal_ex(ctx, md, size);
 312     EVP_MD_CTX_reset(ctx);
 313     return ret;
 314 }
 315
 316 /* The caller can assume that this removes any secret data from the context */
 317 int EVP_DigestFinal_ex(EVP_MD_CTX *ctx, unsigned char *md, unsigned int *isize)
 318 {
 319     int ret;
 320     size_t size = 0;
 321     size_t mdsize = EVP_MD_size(ctx->digest);
 322
 323     if (ctx->digest == NULL || ctx->digest->prov == NULL)
 324         goto legacy;
 325
 326     if (ctx->digest->dfinal == NULL) {
 327         EVPerr(EVP_F_EVP_DIGESTFINAL_EX, EVP_R_FINAL_ERROR);
 328         return 0;
 329     }
 330
 331     ret = ctx->digest->dfinal(ctx->provctx, md, &size, mdsize);
 332
 333     if (isize != NULL) {
 334         if (size <= UINT_MAX) {
 335             *isize = (int)size;
 336         } else {
 337             EVPerr(EVP_F_EVP_DIGESTFINAL_EX, EVP_R_FINAL_ERROR);
 338             ret = 0;
 339         }
 340     }
 341
 342     EVP_MD_CTX_reset(ctx);
 343     return ret;
 344
 345     /* TODO(3.0): Remove legacy code below */
 346  legacy:
 347     OPENSSL_assert(mdsize <= EVP_MAX_MD_SIZE);
 348     ret = ctx->digest->final(ctx, md);
 349     if (isize != NULL)
 350         *isize = mdsize;
 351     if (ctx->digest->cleanup) {
 352         ctx->digest->cleanup(ctx);
 353         EVP_MD_CTX_set_flags(ctx, EVP_MD_CTX_FLAG_CLEANED);
 354     }
 355     OPENSSL_cleanse(ctx->md_data, ctx->digest->ctx_size);
 356     return ret;
 357 }
 358
 359 int EVP_DigestFinalXOF(EVP_MD_CTX *ctx, unsigned char *md, size_t size)
 360 {
 361     int ret = 0;
 362     OSSL_PARAM params[2];
 363     size_t i = 0;
 364
 365     if (ctx->digest == NULL || ctx->digest->prov == NULL)
 366         goto legacy;
 367
 368     if (ctx->digest->dfinal == NULL) {
 369         EVPerr(EVP_F_EVP_DIGESTFINALXOF, EVP_R_FINAL_ERROR);
 370         return 0;
 371     }
 372
 373     params[i++] = OSSL_PARAM_construct_size_t(OSSL_DIGEST_PARAM_XOFLEN, &size);
 374     params[i++] = OSSL_PARAM_construct_end();
 375
 376     if (EVP_MD_CTX_set_params(ctx, params) > 0)
 377         ret = ctx->digest->dfinal(ctx->provctx, md, &size, size);
 378     EVP_MD_CTX_reset(ctx);
 379     return ret;
 380
 381 legacy:
 382     if (ctx->digest->flags & EVP_MD_FLAG_XOF
 383         && size <= INT_MAX
 384         && ctx->digest->md_ctrl(ctx, EVP_MD_CTRL_XOF_LEN, (int)size, NULL)) {
 385         ret = ctx->digest->final(ctx, md);
 386         if (ctx->digest->cleanup != NULL) {
 387             ctx->digest->cleanup(ctx);
 388             EVP_MD_CTX_set_flags(ctx, EVP_MD_CTX_FLAG_CLEANED);
 389         }
 390         OPENSSL_cleanse(ctx->md_data, ctx->digest->ctx_size);
 391     } else {
 392         EVPerr(EVP_F_EVP_DIGESTFINALXOF, EVP_R_NOT_XOF_OR_INVALID_LENGTH);
 393     }
 394
 395     return ret;
 396 }
 397
 398 int EVP_MD_CTX_copy(EVP_MD_CTX *out, const EVP_MD_CTX *in)
 399 {
 400     EVP_MD_CTX_reset(out);
 401     return EVP_MD_CTX_copy_ex(out, in);
 402 }
 403
 404 int EVP_MD_CTX_copy_ex(EVP_MD_CTX *out, const EVP_MD_CTX *in)
 405 {
 406     unsigned char *tmp_buf;
 407
 408     if (in == NULL || in->digest == NULL) {
 409         EVPerr(EVP_F_EVP_MD_CTX_COPY_EX, EVP_R_INPUT_NOT_INITIALIZED);
 410         return 0;
 411     }
 412
 413     if (in->digest->prov == NULL)
 414         goto legacy;
 415
 416     if (in->digest->dupctx == NULL) {
 417         EVPerr(EVP_F_EVP_MD_CTX_COPY_EX, EVP_R_NOT_ABLE_TO_COPY_CTX);
 418         return 0;
 419     }
 420
 421     EVP_MD_CTX_reset(out);
 422     if (out->fetched_digest != NULL)
 423         EVP_MD_free(out->fetched_digest);
 424     *out = *in;
 425     /* NULL out pointers in case of error */
 426     out->pctx = NULL;
 427     out->provctx = NULL;
 428
 429     if (in->fetched_digest != NULL)
 430         EVP_MD_up_ref(in->fetched_digest);
 431
 432     out->provctx = in->digest->dupctx(in->provctx);
 433     if (out->provctx == NULL) {
 434         EVPerr(EVP_F_EVP_MD_CTX_COPY_EX, EVP_R_NOT_ABLE_TO_COPY_CTX);
 435         return 0;
 436     }
 437
 438     /* copied EVP_MD_CTX should free the copied EVP_PKEY_CTX */
 439     EVP_MD_CTX_clear_flags(out, EVP_MD_CTX_FLAG_KEEP_PKEY_CTX);
 440 #ifndef FIPS_MODE
 441     /* TODO(3.0): Temporarily no support for EVP_DigestSign* in FIPS module */
 442     if (in->pctx != NULL) {
 443         out->pctx = EVP_PKEY_CTX_dup(in->pctx);
 444         if (out->pctx == NULL) {
 445             EVPerr(EVP_F_EVP_MD_CTX_COPY_EX, EVP_R_NOT_ABLE_TO_COPY_CTX);
 446             EVP_MD_CTX_reset(out);
 447             return 0;
 448         }
 449     }
 450 #endif
 451
 452     return 1;
 453
 454     /* TODO(3.0): Remove legacy code below */
 455  legacy:
 456 #if !defined(OPENSSL_NO_ENGINE) && !defined(FIPS_MODE)
 457     /* Make sure it's safe to copy a digest context using an ENGINE */
 458     if (in->engine && !ENGINE_init(in->engine)) {
 459         EVPerr(EVP_F_EVP_MD_CTX_COPY_EX, ERR_R_ENGINE_LIB);
 460         return 0;
 461     }
 462 #endif
 463
 464     if (out->digest == in->digest) {
 465         tmp_buf = out->md_data;
 466         EVP_MD_CTX_set_flags(out, EVP_MD_CTX_FLAG_REUSE);
 467     } else
 468         tmp_buf = NULL;
 469     EVP_MD_CTX_reset(out);
 470     memcpy(out, in, sizeof(*out));
 471
 472     /* copied EVP_MD_CTX should free the copied EVP_PKEY_CTX */
 473     EVP_MD_CTX_clear_flags(out, EVP_MD_CTX_FLAG_KEEP_PKEY_CTX);
 474
 475     /* Null these variables, since they are getting fixed up
 476      * properly below.  Anything else may cause a memleak and/or
 477      * double free if any of the memory allocations below fail
 478      */
 479     out->md_data = NULL;
 480     out->pctx = NULL;
 481
 482     if (in->md_data && out->digest->ctx_size) {
 483         if (tmp_buf)
 484             out->md_data = tmp_buf;
 485         else {
 486             out->md_data = OPENSSL_malloc(out->digest->ctx_size);
 487             if (out->md_data == NULL) {
 488                 EVPerr(EVP_F_EVP_MD_CTX_COPY_EX, ERR_R_MALLOC_FAILURE);
 489                 return 0;
 490             }
 491         }
 492         memcpy(out->md_data, in->md_data, out->digest->ctx_size);
 493     }
 494
 495     out->update = in->update;
 496
 497 #ifndef FIPS_MODE
 498     /* TODO(3.0): Temporarily no support for EVP_DigestSign* in FIPS module */
 499     if (in->pctx) {
 500         out->pctx = EVP_PKEY_CTX_dup(in->pctx);
 501         if (!out->pctx) {
 502             EVP_MD_CTX_reset(out);
 503             return 0;
 504         }
 505     }
 506 #endif
 507
 508     if (out->digest->copy)
 509         return out->digest->copy(out, in);
 510
 511     return 1;
 512 }
 513
 514 int EVP_Digest(const void *data, size_t count,
 515                unsigned char *md, unsigned int *size, const EVP_MD *type,
 516                ENGINE *impl)
 517 {
 518     EVP_MD_CTX *ctx = EVP_MD_CTX_new();
 519     int ret;
 520
 521     if (ctx == NULL)
 522         return 0;
 523     EVP_MD_CTX_set_flags(ctx, EVP_MD_CTX_FLAG_ONESHOT);
 524     ret = EVP_DigestInit_ex(ctx, type, impl)
 525         && EVP_DigestUpdate(ctx, data, count)
 526         && EVP_DigestFinal_ex(ctx, md, size);
 527     EVP_MD_CTX_free(ctx);
 528
 529     return ret;
 530 }
 531
 532 int EVP_MD_get_params(const EVP_MD *digest, OSSL_PARAM params[])
 533 {
 534     if (digest != NULL && digest->get_params != NULL)
 535         return digest->get_params(params);
 536     return 0;
 537 }
 538
 539 const OSSL_PARAM *EVP_MD_gettable_params(const EVP_MD *digest)
 540 {
 541     if (digest != NULL && digest->gettable_params != NULL)
 542         return digest->gettable_params();
 543     return NULL;
 544 }
 545
 546 int EVP_MD_CTX_set_params(EVP_MD_CTX *ctx, const OSSL_PARAM params[])
 547 {
 548     if (ctx->digest != NULL && ctx->digest->set_ctx_params != NULL)
 549         return ctx->digest->set_ctx_params(ctx->provctx, params);
 550     return 0;
 551 }
 552
 553 const OSSL_PARAM *EVP_MD_settable_ctx_params(const EVP_MD *md)
 554 {
 555     if (md != NULL && md->settable_ctx_params != NULL)
 556         return md->settable_ctx_params();
 557     return NULL;
 558 }
 559
 560 const OSSL_PARAM *EVP_MD_CTX_settable_params(EVP_MD_CTX *ctx)
 561 {
 562     if (ctx != NULL
 563             && ctx->digest != NULL
 564             && ctx->digest->settable_ctx_params != NULL)
 565         return ctx->digest->settable_ctx_params();
 566
 567     return NULL;
 568 }
 569
 570 int EVP_MD_CTX_get_params(EVP_MD_CTX *ctx, OSSL_PARAM params[])
 571 {
 572     if (ctx->digest != NULL && ctx->digest->get_params != NULL)
 573         return ctx->digest->get_ctx_params(ctx->provctx, params);
 574     return 0;
 575 }
 576
 577 const OSSL_PARAM *EVP_MD_gettable_ctx_params(const EVP_MD *md)
 578 {
 579     if (md != NULL && md->gettable_ctx_params != NULL)
 580         return md->gettable_ctx_params();
 581     return NULL;
 582 }
 583
 584 const OSSL_PARAM *EVP_MD_CTX_gettable_params(EVP_MD_CTX *ctx)
 585 {
 586     if (ctx != NULL
 587             && ctx->digest != NULL
 588             && ctx->digest->gettable_ctx_params != NULL)
 589         return ctx->digest->gettable_ctx_params();
 590
 591     return NULL;
 592 }
 593
 594 /* TODO(3.0): Remove legacy code below - only used by engines & DigestSign */
 595 int EVP_MD_CTX_ctrl(EVP_MD_CTX *ctx, int cmd, int p1, void *p2)
 596 {
 597     int ret = EVP_CTRL_RET_UNSUPPORTED;
 598     int set_params = 1;
 599     size_t sz;
 600     OSSL_PARAM params[2] = { OSSL_PARAM_END, OSSL_PARAM_END };
 601
 602     if (ctx == NULL || ctx->digest == NULL) {
 603         ERR_raise(ERR_LIB_EVP, EVP_R_MESSAGE_DIGEST_IS_NULL);
 604         return 0;
 605     }
 606
 607     if (ctx->digest->prov == NULL)
 608         goto legacy;
 609
 610     switch (cmd) {
 611     case EVP_MD_CTRL_XOF_LEN:
 612         sz = (size_t)p1;
 613         params[0] = OSSL_PARAM_construct_size_t(OSSL_DIGEST_PARAM_XOFLEN, &sz);
 614         break;
 615     case EVP_MD_CTRL_MICALG:
 616         set_params = 0;
 617         params[0] = OSSL_PARAM_construct_utf8_string(OSSL_DIGEST_PARAM_MICALG,
 618                                                      p2, p1 ? p1 : 9999);
 619         break;
 620     default:
 621         return EVP_CTRL_RET_UNSUPPORTED;
 622     }
 623
 624     if (set_params)
 625         ret = evp_do_md_ctx_setparams(ctx->digest, ctx->provctx, params);
 626     else
 627         ret = evp_do_md_ctx_getparams(ctx->digest, ctx->provctx, params);
 628     return ret;
 629
 630
 631 /* TODO(3.0): Remove legacy code below */
 632  legacy:
 633     if (ctx->digest->md_ctrl == NULL) {
 634         ERR_raise(ERR_LIB_EVP, EVP_R_CTRL_NOT_IMPLEMENTED);
 635         return 0;
 636     }
 637
 638     ret = ctx->digest->md_ctrl(ctx, cmd, p1, p2);
 639     if (ret <= 0)
 640         return 0;
 641     return ret;
 642 }
 643
 644 EVP_MD *evp_md_new(void)
 645 {
 646     EVP_MD *md = OPENSSL_zalloc(sizeof(*md));
 647
 648     if (md != NULL) {
 649         md->lock = CRYPTO_THREAD_lock_new();
 650         if (md->lock == NULL) {
 651             OPENSSL_free(md);
 652             return NULL;
 653         }
 654         md->refcnt = 1;
 655     }
 656     return md;
 657 }
 658
 659 /*
 660  * FIPS module note: since internal fetches will be entirely
 661  * provider based, we know that none of its code depends on legacy
 662  * NIDs or any functionality that use them.
 663  */
 664 #ifndef FIPS_MODE
 665 /* TODO(3.x) get rid of the need for legacy NIDs */
 666 static void set_legacy_nid(const char *name, void *vlegacy_nid)
 667 {
 668     int nid;
 669     int *legacy_nid = vlegacy_nid;
 670
 671     if (*legacy_nid == -1)       /* We found a clash already */
 672         return;
 673     if ((nid = OBJ_sn2nid(name)) == NID_undef
 674         && (nid = OBJ_ln2nid(name)) == NID_undef)
 675         return;
 676     if (*legacy_nid != NID_undef && *legacy_nid != nid) {
 677         *legacy_nid = -1;
 678         return;
 679     }
 680     *legacy_nid = nid;
 681 }
 682 #endif
 683
 684 static void *evp_md_from_dispatch(int name_id,
 685                                   const OSSL_DISPATCH *fns,
 686                                   OSSL_PROVIDER *prov, void *unused)
 687 {
 688     EVP_MD *md = NULL;
 689     int fncnt = 0;
 690
 691     /* EVP_MD_fetch() will set the legacy NID if available */
 692     if ((md = evp_md_new()) == NULL) {
 693         EVPerr(0, ERR_R_MALLOC_FAILURE);
 694         return NULL;
 695     }
 696
 697 #ifndef FIPS_MODE
 698     /* TODO(3.x) get rid of the need for legacy NIDs */
 699     md->type = NID_undef;
 700     evp_doall_names(prov, name_id, set_legacy_nid, &md->type);
 701     if (md->type == -1) {
 702         ERR_raise(ERR_LIB_EVP, ERR_R_INTERNAL_ERROR);
 703         EVP_MD_free(md);
 704         return NULL;
 705     }
 706 #endif
 707
 708     md->name_id = name_id;
 709
 710     for (; fns->function_id != 0; fns++) {
 711         switch (fns->function_id) {
 712         case OSSL_FUNC_DIGEST_NEWCTX:
 713             if (md->newctx == NULL) {
 714                 md->newctx = OSSL_get_OP_digest_newctx(fns);
 715                 fncnt++;
 716             }
 717             break;
 718         case OSSL_FUNC_DIGEST_INIT:
 719             if (md->dinit == NULL) {
 720                 md->dinit = OSSL_get_OP_digest_init(fns);
 721                 fncnt++;
 722             }
 723             break;
 724         case OSSL_FUNC_DIGEST_UPDATE:
 725             if (md->dupdate == NULL) {
 726                 md->dupdate = OSSL_get_OP_digest_update(fns);
 727                 fncnt++;
 728             }
 729             break;
 730         case OSSL_FUNC_DIGEST_FINAL:
 731             if (md->dfinal == NULL) {
 732                 md->dfinal = OSSL_get_OP_digest_final(fns);
 733                 fncnt++;
 734             }
 735             break;
 736         case OSSL_FUNC_DIGEST_DIGEST:
 737             if (md->digest == NULL)
 738                 md->digest = OSSL_get_OP_digest_digest(fns);
 739             /* We don't increment fnct for this as it is stand alone */
 740             break;
 741         case OSSL_FUNC_DIGEST_FREECTX:
 742             if (md->freectx == NULL) {
 743                 md->freectx = OSSL_get_OP_digest_freectx(fns);
 744                 fncnt++;
 745             }
 746             break;
 747         case OSSL_FUNC_DIGEST_DUPCTX:
 748             if (md->dupctx == NULL)
 749                 md->dupctx = OSSL_get_OP_digest_dupctx(fns);
 750             break;
 751         case OSSL_FUNC_DIGEST_GET_PARAMS:
 752             if (md->get_params == NULL)
 753                 md->get_params = OSSL_get_OP_digest_get_params(fns);
 754             break;
 755         case OSSL_FUNC_DIGEST_SET_CTX_PARAMS:
 756             if (md->set_ctx_params == NULL)
 757                 md->set_ctx_params = OSSL_get_OP_digest_set_ctx_params(fns);
 758             break;
 759         case OSSL_FUNC_DIGEST_GET_CTX_PARAMS:
 760             if (md->get_ctx_params == NULL)
 761                 md->get_ctx_params = OSSL_get_OP_digest_get_ctx_params(fns);
 762             break;
 763         case OSSL_FUNC_DIGEST_GETTABLE_PARAMS:
 764             if (md->gettable_params == NULL)
 765                 md->gettable_params = OSSL_get_OP_digest_gettable_params(fns);
 766             break;
 767         case OSSL_FUNC_DIGEST_SETTABLE_CTX_PARAMS:
 768             if (md->settable_ctx_params == NULL)
 769                 md->settable_ctx_params =
 770                     OSSL_get_OP_digest_settable_ctx_params(fns);
 771             break;
 772         case OSSL_FUNC_DIGEST_GETTABLE_CTX_PARAMS:
 773             if (md->gettable_ctx_params == NULL)
 774                 md->gettable_ctx_params =
 775                     OSSL_get_OP_digest_gettable_ctx_params(fns);
 776             break;
 777         }
 778     }
 779     if ((fncnt != 0 && fncnt != 5)
 780         || (fncnt == 0 && md->digest == NULL)) {
 781         /*
 782          * In order to be a consistent set of functions we either need the
 783          * whole set of init/update/final etc functions or none of them.
 784          * The "digest" function can standalone. We at least need one way to
 785          * generate digests.
 786          */
 787         EVP_MD_free(md);
 788         ERR_raise(ERR_LIB_EVP, EVP_R_INVALID_PROVIDER_FUNCTIONS);
 789         return NULL;
 790     }
 791     md->prov = prov;
 792     if (prov != NULL)
 793         ossl_provider_up_ref(prov);
 794
 795     return md;
 796 }
 797
 798 static int evp_md_up_ref(void *md)
 799 {
 800     return EVP_MD_up_ref(md);
 801 }
 802
 803 static void evp_md_free(void *md)
 804 {
 805     EVP_MD_free(md);
 806 }
 807
 808 EVP_MD *EVP_MD_fetch(OPENSSL_CTX *ctx, const char *algorithm,
 809                      const char *properties)
 810 {
 811     EVP_MD *md =
 812         evp_generic_fetch(ctx, OSSL_OP_DIGEST, algorithm, properties,
 813                           evp_md_from_dispatch, NULL, evp_md_up_ref,
 814                           evp_md_free);
 815
 816     return md;
 817 }
 818
 819 int EVP_MD_up_ref(EVP_MD *md)
 820 {
 821     int ref = 0;
 822
 823     CRYPTO_UP_REF(&md->refcnt, &ref, md->lock);
 824     return 1;
 825 }
 826
 827 void EVP_MD_free(EVP_MD *md)
 828 {
 829     int i;
 830
 831     if (md == NULL)
 832         return;
 833
 834     CRYPTO_DOWN_REF(&md->refcnt, &i, md->lock);
 835     if (i > 0)
 836         return;
 837     ossl_provider_free(md->prov);
 838     CRYPTO_THREAD_lock_free(md->lock);
 839     OPENSSL_free(md);
 840 }
 841
 842 void EVP_MD_do_all_ex(OPENSSL_CTX *libctx,
 843                           void (*fn)(EVP_MD *mac, void *arg),
 844                           void *arg)
 845 {
 846     evp_generic_do_all(libctx, OSSL_OP_DIGEST,
 847                        (void (*)(void *, void *))fn, arg,
 848                        evp_md_from_dispatch, NULL, evp_md_free);
 849 }