providers/implementations/signature/dsa.c

   1 /*
   2  * Copyright 2019-2020 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 /*
  11  * DSA low level APIs are deprecated for public use, but still ok for
  12  * internal use.
  13  */
  14 #include "internal/deprecated.h"
  15
  16 #include <string.h>
  17
  18 #include <openssl/crypto.h>
  19 #include <openssl/core_dispatch.h>
  20 #include <openssl/core_names.h>
  21 #include <openssl/err.h>
  22 #include <openssl/dsa.h>
  23 #include <openssl/params.h>
  24 #include <openssl/evp.h>
  25 #include <openssl/err.h>
  26 #include "internal/nelem.h"
  27 #include "internal/sizes.h"
  28 #include "internal/cryptlib.h"
  29 #include "prov/providercommon.h"
  30 #include "prov/implementations.h"
  31 #include "prov/providercommonerr.h"
  32 #include "prov/provider_ctx.h"
  33 #include "prov/securitycheck.h"
  34 #include "crypto/dsa.h"
  35 #include "prov/der_dsa.h"
  36
  37 static OSSL_FUNC_signature_newctx_fn dsa_newctx;
  38 static OSSL_FUNC_signature_sign_init_fn dsa_sign_init;
  39 static OSSL_FUNC_signature_verify_init_fn dsa_verify_init;
  40 static OSSL_FUNC_signature_sign_fn dsa_sign;
  41 static OSSL_FUNC_signature_verify_fn dsa_verify;
  42 static OSSL_FUNC_signature_digest_sign_init_fn dsa_digest_sign_init;
  43 static OSSL_FUNC_signature_digest_sign_update_fn dsa_digest_signverify_update;
  44 static OSSL_FUNC_signature_digest_sign_final_fn dsa_digest_sign_final;
  45 static OSSL_FUNC_signature_digest_verify_init_fn dsa_digest_verify_init;
  46 static OSSL_FUNC_signature_digest_verify_update_fn dsa_digest_signverify_update;
  47 static OSSL_FUNC_signature_digest_verify_final_fn dsa_digest_verify_final;
  48 static OSSL_FUNC_signature_freectx_fn dsa_freectx;
  49 static OSSL_FUNC_signature_dupctx_fn dsa_dupctx;
  50 static OSSL_FUNC_signature_get_ctx_params_fn dsa_get_ctx_params;
  51 static OSSL_FUNC_signature_gettable_ctx_params_fn dsa_gettable_ctx_params;
  52 static OSSL_FUNC_signature_set_ctx_params_fn dsa_set_ctx_params;
  53 static OSSL_FUNC_signature_settable_ctx_params_fn dsa_settable_ctx_params;
  54 static OSSL_FUNC_signature_get_ctx_md_params_fn dsa_get_ctx_md_params;
  55 static OSSL_FUNC_signature_gettable_ctx_md_params_fn dsa_gettable_ctx_md_params;
  56 static OSSL_FUNC_signature_set_ctx_md_params_fn dsa_set_ctx_md_params;
  57 static OSSL_FUNC_signature_settable_ctx_md_params_fn dsa_settable_ctx_md_params;
  58
  59 /*
  60  * What's passed as an actual key is defined by the KEYMGMT interface.
  61  * We happen to know that our KEYMGMT simply passes DSA structures, so
  62  * we use that here too.
  63  */
  64
  65 typedef struct {
  66     OSSL_LIB_CTX *libctx;
  67     char *propq;
  68     DSA *dsa;
  69
  70     /*
  71      * Flag to determine if the hash function can be changed (1) or not (0)
  72      * Because it's dangerous to change during a DigestSign or DigestVerify
  73      * operation, this flag is cleared by their Init function, and set again
  74      * by their Final function.
  75      */
  76     unsigned int flag_allow_md : 1;
  77
  78     char mdname[OSSL_MAX_NAME_SIZE];
  79
  80     /* The Algorithm Identifier of the combined signature algorithm */
  81     unsigned char aid_buf[OSSL_MAX_ALGORITHM_ID_SIZE];
  82     unsigned char *aid;
  83     size_t  aid_len;
  84
  85     /* main digest */
  86     EVP_MD *md;
  87     EVP_MD_CTX *mdctx;
  88     size_t mdsize;
  89     int operation;
  90 } PROV_DSA_CTX;
  91
  92
  93 static size_t dsa_get_md_size(const PROV_DSA_CTX *pdsactx)
  94 {
  95     if (pdsactx->md != NULL)
  96         return EVP_MD_size(pdsactx->md);
  97     return 0;
  98 }
  99
 100 static void *dsa_newctx(void *provctx, const char *propq)
 101 {
 102     PROV_DSA_CTX *pdsactx;
 103
 104     if (!ossl_prov_is_running())
 105         return NULL;
 106
 107     pdsactx = OPENSSL_zalloc(sizeof(PROV_DSA_CTX));
 108     if (pdsactx == NULL)
 109         return NULL;
 110
 111     pdsactx->libctx = PROV_LIBRARY_CONTEXT_OF(provctx);
 112     pdsactx->flag_allow_md = 1;
 113     if (propq != NULL && (pdsactx->propq = OPENSSL_strdup(propq)) == NULL) {
 114         OPENSSL_free(pdsactx);
 115         pdsactx = NULL;
 116         ERR_raise(ERR_LIB_PROV, ERR_R_MALLOC_FAILURE);
 117     }
 118     return pdsactx;
 119 }
 120
 121 static int dsa_setup_md(PROV_DSA_CTX *ctx,
 122                         const char *mdname, const char *mdprops)
 123 {
 124     if (mdprops == NULL)
 125         mdprops = ctx->propq;
 126
 127     if (mdname != NULL) {
 128         int sha1_allowed = (ctx->operation != EVP_PKEY_OP_SIGN);
 129         WPACKET pkt;
 130         EVP_MD *md = EVP_MD_fetch(ctx->libctx, mdname, mdprops);
 131         int md_nid = digest_get_approved_nid_with_sha1(md, sha1_allowed);
 132         size_t mdname_len = strlen(mdname);
 133
 134         if (md == NULL || md_nid == NID_undef) {
 135             if (md == NULL)
 136                 ERR_raise_data(ERR_LIB_PROV, PROV_R_INVALID_DIGEST,
 137                                "%s could not be fetched", mdname);
 138             if (md_nid == NID_undef)
 139                 ERR_raise_data(ERR_LIB_PROV, PROV_R_DIGEST_NOT_ALLOWED,
 140                                "digest=%s", mdname);
 141             if (mdname_len >= sizeof(ctx->mdname))
 142                 ERR_raise_data(ERR_LIB_PROV, PROV_R_INVALID_DIGEST,
 143                                "%s exceeds name buffer length", mdname);
 144             EVP_MD_free(md);
 145             return 0;
 146         }
 147
 148         EVP_MD_CTX_free(ctx->mdctx);
 149         EVP_MD_free(ctx->md);
 150
 151         /*
 152          * TODO(3.0) Should we care about DER writing errors?
 153          * All it really means is that for some reason, there's no
 154          * AlgorithmIdentifier to be had, but the operation itself is
 155          * still valid, just as long as it's not used to construct
 156          * anything that needs an AlgorithmIdentifier.
 157          */
 158         ctx->aid_len = 0;
 159         if (WPACKET_init_der(&pkt, ctx->aid_buf, sizeof(ctx->aid_buf))
 160             && ossl_DER_w_algorithmIdentifier_DSA_with_MD(&pkt, -1, ctx->dsa,
 161                                                           md_nid)
 162             && WPACKET_finish(&pkt)) {
 163             WPACKET_get_total_written(&pkt, &ctx->aid_len);
 164             ctx->aid = WPACKET_get_curr(&pkt);
 165         }
 166         WPACKET_cleanup(&pkt);
 167
 168         ctx->mdctx = NULL;
 169         ctx->md = md;
 170         OPENSSL_strlcpy(ctx->mdname, mdname, sizeof(ctx->mdname));
 171     }
 172     return 1;
 173 }
 174
 175 static int dsa_signverify_init(void *vpdsactx, void *vdsa, int operation)
 176 {
 177     PROV_DSA_CTX *pdsactx = (PROV_DSA_CTX *)vpdsactx;
 178
 179     if (!ossl_prov_is_running()
 180             || pdsactx == NULL
 181             || vdsa == NULL
 182             || !DSA_up_ref(vdsa))
 183         return 0;
 184     DSA_free(pdsactx->dsa);
 185     pdsactx->dsa = vdsa;
 186     pdsactx->operation = operation;
 187     if (!dsa_check_key(vdsa, operation == EVP_PKEY_OP_SIGN)) {
 188         ERR_raise(ERR_LIB_PROV, PROV_R_INVALID_KEY_LENGTH);
 189         return 0;
 190     }
 191     return 1;
 192 }
 193
 194 static int dsa_sign_init(void *vpdsactx, void *vdsa)
 195 {
 196     return dsa_signverify_init(vpdsactx, vdsa, EVP_PKEY_OP_SIGN);
 197 }
 198
 199 static int dsa_verify_init(void *vpdsactx, void *vdsa)
 200 {
 201     return dsa_signverify_init(vpdsactx, vdsa, EVP_PKEY_OP_VERIFY);
 202 }
 203
 204 static int dsa_sign(void *vpdsactx, unsigned char *sig, size_t *siglen,
 205                     size_t sigsize, const unsigned char *tbs, size_t tbslen)
 206 {
 207     PROV_DSA_CTX *pdsactx = (PROV_DSA_CTX *)vpdsactx;
 208     int ret;
 209     unsigned int sltmp;
 210     size_t dsasize = DSA_size(pdsactx->dsa);
 211     size_t mdsize = dsa_get_md_size(pdsactx);
 212
 213     if (!ossl_prov_is_running())
 214         return 0;
 215
 216     if (sig == NULL) {
 217         *siglen = dsasize;
 218         return 1;
 219     }
 220
 221     if (sigsize < (size_t)dsasize)
 222         return 0;
 223
 224     if (mdsize != 0 && tbslen != mdsize)
 225         return 0;
 226
 227     ret = dsa_sign_int(0, tbs, tbslen, sig, &sltmp, pdsactx->dsa);
 228     if (ret <= 0)
 229         return 0;
 230
 231     *siglen = sltmp;
 232     return 1;
 233 }
 234
 235 static int dsa_verify(void *vpdsactx, const unsigned char *sig, size_t siglen,
 236                       const unsigned char *tbs, size_t tbslen)
 237 {
 238     PROV_DSA_CTX *pdsactx = (PROV_DSA_CTX *)vpdsactx;
 239     size_t mdsize = dsa_get_md_size(pdsactx);
 240
 241     if (!ossl_prov_is_running() || (mdsize != 0 && tbslen != mdsize))
 242         return 0;
 243
 244     return DSA_verify(0, tbs, tbslen, sig, siglen, pdsactx->dsa);
 245 }
 246
 247 static int dsa_digest_signverify_init(void *vpdsactx, const char *mdname,
 248                                       void *vdsa, int operation)
 249 {
 250     PROV_DSA_CTX *pdsactx = (PROV_DSA_CTX *)vpdsactx;
 251
 252     if (!ossl_prov_is_running())
 253         return 0;
 254
 255     pdsactx->flag_allow_md = 0;
 256     if (!dsa_signverify_init(vpdsactx, vdsa, operation))
 257         return 0;
 258
 259     if (!dsa_setup_md(pdsactx, mdname, NULL))
 260         return 0;
 261
 262     pdsactx->mdctx = EVP_MD_CTX_new();
 263     if (pdsactx->mdctx == NULL)
 264         goto error;
 265
 266     if (!EVP_DigestInit_ex(pdsactx->mdctx, pdsactx->md, NULL))
 267         goto error;
 268
 269     return 1;
 270
 271  error:
 272     EVP_MD_CTX_free(pdsactx->mdctx);
 273     EVP_MD_free(pdsactx->md);
 274     pdsactx->mdctx = NULL;
 275     pdsactx->md = NULL;
 276     return 0;
 277 }
 278
 279 static int dsa_digest_sign_init(void *vpdsactx, const char *mdname,
 280                                       void *vdsa)
 281 {
 282     return dsa_digest_signverify_init(vpdsactx, mdname, vdsa, EVP_PKEY_OP_SIGN);
 283 }
 284
 285 static int dsa_digest_verify_init(void *vpdsactx, const char *mdname, void *vdsa)
 286 {
 287     return dsa_digest_signverify_init(vpdsactx, mdname, vdsa, EVP_PKEY_OP_VERIFY);
 288 }
 289
 290 int dsa_digest_signverify_update(void *vpdsactx, const unsigned char *data,
 291                                  size_t datalen)
 292 {
 293     PROV_DSA_CTX *pdsactx = (PROV_DSA_CTX *)vpdsactx;
 294
 295     if (pdsactx == NULL || pdsactx->mdctx == NULL)
 296         return 0;
 297
 298     return EVP_DigestUpdate(pdsactx->mdctx, data, datalen);
 299 }
 300
 301 int dsa_digest_sign_final(void *vpdsactx, unsigned char *sig, size_t *siglen,
 302                           size_t sigsize)
 303 {
 304     PROV_DSA_CTX *pdsactx = (PROV_DSA_CTX *)vpdsactx;
 305     unsigned char digest[EVP_MAX_MD_SIZE];
 306     unsigned int dlen = 0;
 307
 308     if (!ossl_prov_is_running() || pdsactx == NULL || pdsactx->mdctx == NULL)
 309         return 0;
 310
 311     /*
 312      * If sig is NULL then we're just finding out the sig size. Other fields
 313      * are ignored. Defer to dsa_sign.
 314      */
 315     if (sig != NULL) {
 316         /*
 317          * TODO(3.0): There is the possibility that some externally provided
 318          * digests exceed EVP_MAX_MD_SIZE. We should probably handle that somehow -
 319          * but that problem is much larger than just in DSA.
 320          */
 321         if (!EVP_DigestFinal_ex(pdsactx->mdctx, digest, &dlen))
 322             return 0;
 323     }
 324
 325     pdsactx->flag_allow_md = 1;
 326
 327     return dsa_sign(vpdsactx, sig, siglen, sigsize, digest, (size_t)dlen);
 328 }
 329
 330
 331 int dsa_digest_verify_final(void *vpdsactx, const unsigned char *sig,
 332                             size_t siglen)
 333 {
 334     PROV_DSA_CTX *pdsactx = (PROV_DSA_CTX *)vpdsactx;
 335     unsigned char digest[EVP_MAX_MD_SIZE];
 336     unsigned int dlen = 0;
 337
 338     if (!ossl_prov_is_running() || pdsactx == NULL || pdsactx->mdctx == NULL)
 339         return 0;
 340
 341     /*
 342      * TODO(3.0): There is the possibility that some externally provided
 343      * digests exceed EVP_MAX_MD_SIZE. We should probably handle that somehow -
 344      * but that problem is much larger than just in DSA.
 345      */
 346     if (!EVP_DigestFinal_ex(pdsactx->mdctx, digest, &dlen))
 347         return 0;
 348
 349     pdsactx->flag_allow_md = 1;
 350
 351     return dsa_verify(vpdsactx, sig, siglen, digest, (size_t)dlen);
 352 }
 353
 354 static void dsa_freectx(void *vpdsactx)
 355 {
 356     PROV_DSA_CTX *ctx = (PROV_DSA_CTX *)vpdsactx;
 357
 358     OPENSSL_free(ctx->propq);
 359     EVP_MD_CTX_free(ctx->mdctx);
 360     EVP_MD_free(ctx->md);
 361     ctx->propq = NULL;
 362     ctx->mdctx = NULL;
 363     ctx->md = NULL;
 364     ctx->mdsize = 0;
 365     DSA_free(ctx->dsa);
 366     OPENSSL_free(ctx);
 367 }
 368
 369 static void *dsa_dupctx(void *vpdsactx)
 370 {
 371     PROV_DSA_CTX *srcctx = (PROV_DSA_CTX *)vpdsactx;
 372     PROV_DSA_CTX *dstctx;
 373
 374     if (!ossl_prov_is_running())
 375         return NULL;
 376
 377     dstctx = OPENSSL_zalloc(sizeof(*srcctx));
 378     if (dstctx == NULL)
 379         return NULL;
 380
 381     *dstctx = *srcctx;
 382     dstctx->dsa = NULL;
 383     dstctx->md = NULL;
 384     dstctx->mdctx = NULL;
 385
 386     if (srcctx->dsa != NULL && !DSA_up_ref(srcctx->dsa))
 387         goto err;
 388     dstctx->dsa = srcctx->dsa;
 389
 390     if (srcctx->md != NULL && !EVP_MD_up_ref(srcctx->md))
 391         goto err;
 392     dstctx->md = srcctx->md;
 393
 394     if (srcctx->mdctx != NULL) {
 395         dstctx->mdctx = EVP_MD_CTX_new();
 396         if (dstctx->mdctx == NULL
 397                 || !EVP_MD_CTX_copy_ex(dstctx->mdctx, srcctx->mdctx))
 398             goto err;
 399     }
 400
 401     return dstctx;
 402  err:
 403     dsa_freectx(dstctx);
 404     return NULL;
 405 }
 406
 407 static int dsa_get_ctx_params(void *vpdsactx, OSSL_PARAM *params)
 408 {
 409     PROV_DSA_CTX *pdsactx = (PROV_DSA_CTX *)vpdsactx;
 410     OSSL_PARAM *p;
 411
 412     if (pdsactx == NULL || params == NULL)
 413         return 0;
 414
 415     p = OSSL_PARAM_locate(params, OSSL_SIGNATURE_PARAM_ALGORITHM_ID);
 416     if (p != NULL
 417         && !OSSL_PARAM_set_octet_string(p, pdsactx->aid, pdsactx->aid_len))
 418         return 0;
 419
 420     p = OSSL_PARAM_locate(params, OSSL_SIGNATURE_PARAM_DIGEST);
 421     if (p != NULL && !OSSL_PARAM_set_utf8_string(p, pdsactx->mdname))
 422         return 0;
 423
 424     return 1;
 425 }
 426
 427 static const OSSL_PARAM known_gettable_ctx_params[] = {
 428     OSSL_PARAM_octet_string(OSSL_SIGNATURE_PARAM_ALGORITHM_ID, NULL, 0),
 429     OSSL_PARAM_utf8_string(OSSL_SIGNATURE_PARAM_DIGEST, NULL, 0),
 430     OSSL_PARAM_END
 431 };
 432
 433 static const OSSL_PARAM *dsa_gettable_ctx_params(ossl_unused void *vctx)
 434 {
 435     return known_gettable_ctx_params;
 436 }
 437
 438 static int dsa_set_ctx_params(void *vpdsactx, const OSSL_PARAM params[])
 439 {
 440     PROV_DSA_CTX *pdsactx = (PROV_DSA_CTX *)vpdsactx;
 441     const OSSL_PARAM *p;
 442
 443     if (pdsactx == NULL || params == NULL)
 444         return 0;
 445
 446     p = OSSL_PARAM_locate_const(params, OSSL_SIGNATURE_PARAM_DIGEST);
 447     /* Not allowed during certain operations */
 448     if (p != NULL && !pdsactx->flag_allow_md)
 449         return 0;
 450     if (p != NULL) {
 451         char mdname[OSSL_MAX_NAME_SIZE] = "", *pmdname = mdname;
 452         char mdprops[OSSL_MAX_PROPQUERY_SIZE] = "", *pmdprops = mdprops;
 453         const OSSL_PARAM *propsp =
 454             OSSL_PARAM_locate_const(params,
 455                                     OSSL_SIGNATURE_PARAM_PROPERTIES);
 456
 457         if (!OSSL_PARAM_get_utf8_string(p, &pmdname, sizeof(mdname)))
 458             return 0;
 459         if (propsp != NULL
 460             && !OSSL_PARAM_get_utf8_string(propsp, &pmdprops, sizeof(mdprops)))
 461             return 0;
 462         if (!dsa_setup_md(pdsactx, mdname, mdprops))
 463             return 0;
 464     }
 465
 466     return 1;
 467 }
 468
 469 static const OSSL_PARAM known_settable_ctx_params[] = {
 470     OSSL_PARAM_utf8_string(OSSL_SIGNATURE_PARAM_DIGEST, NULL, 0),
 471     OSSL_PARAM_utf8_string(OSSL_SIGNATURE_PARAM_PROPERTIES, NULL, 0),
 472     OSSL_PARAM_END
 473 };
 474
 475 static const OSSL_PARAM *dsa_settable_ctx_params(ossl_unused void *provctx)
 476 {
 477     /*
 478      * TODO(3.0): Should this function return a different set of settable ctx
 479      * params if the ctx is being used for a DigestSign/DigestVerify? In that
 480      * case it is not allowed to set the digest size/digest name because the
 481      * digest is explicitly set as part of the init.
 482      * NOTE: Ideally we would check pdsactx->flag_allow_md, but this is
 483      * problematic because there is no nice way of passing the
 484      * PROV_DSA_CTX down to this function...
 485      * Because we have API's that dont know about their parent..
 486      * e.g: EVP_SIGNATURE_gettable_ctx_params(const EVP_SIGNATURE *sig).
 487      * We could pass NULL for that case (but then how useful is the check?).
 488      */
 489     return known_settable_ctx_params;
 490 }
 491
 492 static int dsa_get_ctx_md_params(void *vpdsactx, OSSL_PARAM *params)
 493 {
 494     PROV_DSA_CTX *pdsactx = (PROV_DSA_CTX *)vpdsactx;
 495
 496     if (pdsactx->mdctx == NULL)
 497         return 0;
 498
 499     return EVP_MD_CTX_get_params(pdsactx->mdctx, params);
 500 }
 501
 502 static const OSSL_PARAM *dsa_gettable_ctx_md_params(void *vpdsactx)
 503 {
 504     PROV_DSA_CTX *pdsactx = (PROV_DSA_CTX *)vpdsactx;
 505
 506     if (pdsactx->md == NULL)
 507         return 0;
 508
 509     return EVP_MD_gettable_ctx_params(pdsactx->md);
 510 }
 511
 512 static int dsa_set_ctx_md_params(void *vpdsactx, const OSSL_PARAM params[])
 513 {
 514     PROV_DSA_CTX *pdsactx = (PROV_DSA_CTX *)vpdsactx;
 515
 516     if (pdsactx->mdctx == NULL)
 517         return 0;
 518
 519     return EVP_MD_CTX_set_params(pdsactx->mdctx, params);
 520 }
 521
 522 static const OSSL_PARAM *dsa_settable_ctx_md_params(void *vpdsactx)
 523 {
 524     PROV_DSA_CTX *pdsactx = (PROV_DSA_CTX *)vpdsactx;
 525
 526     if (pdsactx->md == NULL)
 527         return 0;
 528
 529     return EVP_MD_settable_ctx_params(pdsactx->md);
 530 }
 531
 532 const OSSL_DISPATCH ossl_dsa_signature_functions[] = {
 533     { OSSL_FUNC_SIGNATURE_NEWCTX, (void (*)(void))dsa_newctx },
 534     { OSSL_FUNC_SIGNATURE_SIGN_INIT, (void (*)(void))dsa_sign_init },
 535     { OSSL_FUNC_SIGNATURE_SIGN, (void (*)(void))dsa_sign },
 536     { OSSL_FUNC_SIGNATURE_VERIFY_INIT, (void (*)(void))dsa_verify_init },
 537     { OSSL_FUNC_SIGNATURE_VERIFY, (void (*)(void))dsa_verify },
 538     { OSSL_FUNC_SIGNATURE_DIGEST_SIGN_INIT,
 539       (void (*)(void))dsa_digest_sign_init },
 540     { OSSL_FUNC_SIGNATURE_DIGEST_SIGN_UPDATE,
 541       (void (*)(void))dsa_digest_signverify_update },
 542     { OSSL_FUNC_SIGNATURE_DIGEST_SIGN_FINAL,
 543       (void (*)(void))dsa_digest_sign_final },
 544     { OSSL_FUNC_SIGNATURE_DIGEST_VERIFY_INIT,
 545       (void (*)(void))dsa_digest_verify_init },
 546     { OSSL_FUNC_SIGNATURE_DIGEST_VERIFY_UPDATE,
 547       (void (*)(void))dsa_digest_signverify_update },
 548     { OSSL_FUNC_SIGNATURE_DIGEST_VERIFY_FINAL,
 549       (void (*)(void))dsa_digest_verify_final },
 550     { OSSL_FUNC_SIGNATURE_FREECTX, (void (*)(void))dsa_freectx },
 551     { OSSL_FUNC_SIGNATURE_DUPCTX, (void (*)(void))dsa_dupctx },
 552     { OSSL_FUNC_SIGNATURE_GET_CTX_PARAMS, (void (*)(void))dsa_get_ctx_params },
 553     { OSSL_FUNC_SIGNATURE_GETTABLE_CTX_PARAMS,
 554       (void (*)(void))dsa_gettable_ctx_params },
 555     { OSSL_FUNC_SIGNATURE_SET_CTX_PARAMS, (void (*)(void))dsa_set_ctx_params },
 556     { OSSL_FUNC_SIGNATURE_SETTABLE_CTX_PARAMS,
 557       (void (*)(void))dsa_settable_ctx_params },
 558     { OSSL_FUNC_SIGNATURE_GET_CTX_MD_PARAMS,
 559       (void (*)(void))dsa_get_ctx_md_params },
 560     { OSSL_FUNC_SIGNATURE_GETTABLE_CTX_MD_PARAMS,
 561       (void (*)(void))dsa_gettable_ctx_md_params },
 562     { OSSL_FUNC_SIGNATURE_SET_CTX_MD_PARAMS,
 563       (void (*)(void))dsa_set_ctx_md_params },
 564     { OSSL_FUNC_SIGNATURE_SETTABLE_CTX_MD_PARAMS,
 565       (void (*)(void))dsa_settable_ctx_md_params },
 566     { 0, NULL }
 567 };