providers/implementations/kdfs/x942kdf.c

   1 /*
   2  * Copyright 2019-2021 The OpenSSL Project Authors. All Rights Reserved.
   3  * Copyright (c) 2019, Oracle and/or its affiliates.  All rights reserved.
   4  *
   5  * Licensed under the Apache License 2.0 (the "License").  You may not use
   6  * this file except in compliance with the License.  You can obtain a copy
   7  * in the file LICENSE in the source distribution or at
   8  * https://www.openssl.org/source/license.html
   9  */
  10
  11 #include "internal/e_os.h"
  12 #include <openssl/core_names.h>
  13 #include <openssl/core_dispatch.h>
  14 #include <openssl/err.h>
  15 #include <openssl/evp.h>
  16 #include <openssl/params.h>
  17 #include <openssl/proverr.h>
  18 #include "internal/packet.h"
  19 #include "internal/der.h"
  20 #include "prov/provider_ctx.h"
  21 #include "prov/providercommon.h"
  22 #include "prov/implementations.h"
  23 #include "prov/provider_util.h"
  24 #include "prov/der_wrap.h"
  25
  26 #define X942KDF_MAX_INLEN (1 << 30)
  27
  28 static OSSL_FUNC_kdf_newctx_fn x942kdf_new;
  29 static OSSL_FUNC_kdf_dupctx_fn x942kdf_dup;
  30 static OSSL_FUNC_kdf_freectx_fn x942kdf_free;
  31 static OSSL_FUNC_kdf_reset_fn x942kdf_reset;
  32 static OSSL_FUNC_kdf_derive_fn x942kdf_derive;
  33 static OSSL_FUNC_kdf_settable_ctx_params_fn x942kdf_settable_ctx_params;
  34 static OSSL_FUNC_kdf_set_ctx_params_fn x942kdf_set_ctx_params;
  35 static OSSL_FUNC_kdf_gettable_ctx_params_fn x942kdf_gettable_ctx_params;
  36 static OSSL_FUNC_kdf_get_ctx_params_fn x942kdf_get_ctx_params;
  37
  38 typedef struct {
  39     void *provctx;
  40     PROV_DIGEST digest;
  41     unsigned char *secret;
  42     size_t secret_len;
  43     unsigned char *acvpinfo;
  44     size_t acvpinfo_len;
  45     unsigned char *partyuinfo, *partyvinfo, *supp_pubinfo, *supp_privinfo;
  46     size_t partyuinfo_len, partyvinfo_len, supp_pubinfo_len, supp_privinfo_len;
  47     size_t dkm_len;
  48     const unsigned char *cek_oid;
  49     size_t cek_oid_len;
  50     int use_keybits;
  51 } KDF_X942;
  52
  53 /*
  54  * A table of allowed wrapping algorithms, oids and the associated output
  55  * lengths.
  56  * NOTE: RC2wrap and camellia128_wrap have been removed as there are no
  57  * corresponding ciphers for these operations.
  58  */
  59 static const struct {
  60     const char *name;
  61     const unsigned char *oid;
  62     size_t oid_len;
  63     size_t keklen; /* size in bytes */
  64 } kek_algs[] = {
  65     { "AES-128-WRAP", ossl_der_oid_id_aes128_wrap, DER_OID_SZ_id_aes128_wrap,
  66       16 },
  67     { "AES-192-WRAP", ossl_der_oid_id_aes192_wrap, DER_OID_SZ_id_aes192_wrap,
  68       24 },
  69     { "AES-256-WRAP", ossl_der_oid_id_aes256_wrap, DER_OID_SZ_id_aes256_wrap,
  70       32 },
  71 #ifndef FIPS_MODULE
  72     { "DES3-WRAP", ossl_der_oid_id_alg_CMS3DESwrap,
  73       DER_OID_SZ_id_alg_CMS3DESwrap, 24 },
  74 #endif
  75 };
  76
  77 static int find_alg_id(OSSL_LIB_CTX *libctx, const char *algname,
  78                        const char *propq, size_t *id)
  79 {
  80     int ret = 1;
  81     size_t i;
  82     EVP_CIPHER *cipher;
  83
  84     cipher = EVP_CIPHER_fetch(libctx, algname, propq);
  85     if (cipher != NULL) {
  86         for (i = 0; i < OSSL_NELEM(kek_algs); i++) {
  87             if (EVP_CIPHER_is_a(cipher, kek_algs[i].name)) {
  88                 *id = i;
  89                 goto end;
  90             }
  91         }
  92     }
  93     ret = 0;
  94     ERR_raise(ERR_LIB_PROV, PROV_R_UNSUPPORTED_CEK_ALG);
  95 end:
  96     EVP_CIPHER_free(cipher);
  97     return ret;
  98 }
  99
 100 static int DER_w_keyinfo(WPACKET *pkt,
 101                          const unsigned char *der_oid, size_t der_oidlen,
 102                          unsigned char **pcounter)
 103 {
 104     return ossl_DER_w_begin_sequence(pkt, -1)
 105            /* Store the initial value of 1 into the counter */
 106            && ossl_DER_w_octet_string_uint32(pkt, -1, 1)
 107            /* Remember where we stored the counter in the buffer */
 108            && (pcounter == NULL
 109                || (*pcounter = WPACKET_get_curr(pkt)) != NULL)
 110            && ossl_DER_w_precompiled(pkt, -1, der_oid, der_oidlen)
 111            && ossl_DER_w_end_sequence(pkt, -1);
 112 }
 113
 114 static int der_encode_sharedinfo(WPACKET *pkt, unsigned char *buf, size_t buflen,
 115                                  const unsigned char *der_oid, size_t der_oidlen,
 116                                  const unsigned char *acvp, size_t acvplen,
 117                                  const unsigned char *partyu, size_t partyulen,
 118                                  const unsigned char *partyv, size_t partyvlen,
 119                                  const unsigned char *supp_pub, size_t supp_publen,
 120                                  const unsigned char *supp_priv, size_t supp_privlen,
 121                                  uint32_t keylen_bits, unsigned char **pcounter)
 122 {
 123     return (buf != NULL ? WPACKET_init_der(pkt, buf, buflen) :
 124                           WPACKET_init_null_der(pkt))
 125            && ossl_DER_w_begin_sequence(pkt, -1)
 126            && (supp_priv == NULL
 127                || ossl_DER_w_octet_string(pkt, 3, supp_priv, supp_privlen))
 128            && (supp_pub == NULL
 129                || ossl_DER_w_octet_string(pkt, 2, supp_pub, supp_publen))
 130            && (keylen_bits == 0
 131                || ossl_DER_w_octet_string_uint32(pkt, 2, keylen_bits))
 132            && (partyv == NULL || ossl_DER_w_octet_string(pkt, 1, partyv, partyvlen))
 133            && (partyu == NULL || ossl_DER_w_octet_string(pkt, 0, partyu, partyulen))
 134            && (acvp == NULL || ossl_DER_w_precompiled(pkt, -1, acvp, acvplen))
 135            && DER_w_keyinfo(pkt, der_oid, der_oidlen, pcounter)
 136            && ossl_DER_w_end_sequence(pkt, -1)
 137            && WPACKET_finish(pkt);
 138 }
 139
 140 /*
 141  * Encode the other info structure.
 142  *
 143  * The ANS X9.42-2003 standard uses OtherInfo:
 144  *
 145  *  OtherInfo ::= SEQUENCE {
 146  *      keyInfo KeySpecificInfo,
 147  *      partyUInfo [0] OCTET STRING OPTIONAL,
 148  *      partyVInfo [1] OCTET STRING OPTIONAL,
 149  *      suppPubInfo [2] OCTET STRING OPTIONAL,
 150  *      suppPrivInfo [3] OCTET STRING OPTIONAL
 151  *  }
 152  *
 153  *  KeySpecificInfo ::= SEQUENCE {
 154  *      algorithm OBJECT IDENTIFIER,
 155  *      counter OCTET STRING SIZE (4..4)
 156  *  }
 157  *
 158  *  RFC2631 Section 2.1.2 Contains the following definition for OtherInfo
 159  *
 160  *  OtherInfo ::= SEQUENCE {
 161  *      keyInfo KeySpecificInfo,
 162  *      partyAInfo [0] OCTET STRING OPTIONAL,
 163  *      suppPubInfo [2] OCTET STRING
 164  *  }
 165  *  Where suppPubInfo is the key length (in bits) (stored into 4 bytes)
 166  *
 167  * |keylen| is the length (in bytes) of the generated KEK. It is stored into
 168  *   suppPubInfo (in bits). It is ignored if the value is 0.
 169  * |cek_oid| The oid of the key wrapping algorithm.
 170  * |cek_oidlen| The length (in bytes) of the key wrapping algorithm oid,
 171  * |acvp| is the optional blob of DER data representing one or more of the
 172  *   OtherInfo fields related to |partyu|, |partyv|, |supp_pub| and |supp_priv|.
 173  *   This field should noramlly be NULL. If |acvp| is non NULL then |partyu|,
 174  *   |partyv|, |supp_pub| and |supp_priv| should all be NULL.
 175  * |acvp_len| is the |acvp| length (in bytes).
 176  * |partyu| is the optional public info contributed by the initiator.
 177  *   It can be NULL. (It is also used as the ukm by CMS).
 178  * |partyu_len| is the |partyu| length (in bytes).
 179  * |partyv| is the optional public info contributed by the responder.
 180  *   It can be NULL.
 181  * |partyv_len| is the |partyv| length (in bytes).
 182  * |supp_pub| is the optional additional, mutually-known public information.
 183  *   It can be NULL. |keylen| should be 0 if this is not NULL.
 184  * |supp_pub_len| is the |supp_pub| length (in bytes).
 185  * |supp_priv| is the optional additional, mutually-known private information.
 186  *   It can be NULL.
 187  * |supp_priv_len| is the |supp_priv| length (in bytes).
 188  * |der| is the returned encoded data. It must be freed by the caller.
 189  * |der_len| is the returned size of the encoded data.
 190  * |out_ctr| returns a pointer to the counter data which is embedded inside the
 191  *   encoded data. This allows the counter bytes to be updated without
 192  *   re-encoding.
 193  *
 194  * Returns: 1 if successfully encoded, or 0 otherwise.
 195  * Assumptions: |der|, |der_len| & |out_ctr| are not NULL.
 196  */
 197 static int
 198 x942_encode_otherinfo(size_t keylen,
 199                       const unsigned char *cek_oid, size_t cek_oid_len,
 200                       const unsigned char *acvp, size_t acvp_len,
 201                       const unsigned char *partyu, size_t partyu_len,
 202                       const unsigned char *partyv, size_t partyv_len,
 203                       const unsigned char *supp_pub, size_t supp_pub_len,
 204                       const unsigned char *supp_priv, size_t supp_priv_len,
 205                       unsigned char **der, size_t *der_len,
 206                       unsigned char **out_ctr)
 207 {
 208     int ret = 0;
 209     unsigned char *pcounter = NULL, *der_buf = NULL;
 210     size_t der_buflen = 0;
 211     WPACKET pkt;
 212     uint32_t keylen_bits;
 213
 214     /* keylenbits must fit into 4 bytes */
 215     if (keylen > 0xFFFFFF)
 216         return 0;
 217     keylen_bits = 8 * keylen;
 218
 219     /* Calculate the size of the buffer */
 220     if (!der_encode_sharedinfo(&pkt, NULL, 0, cek_oid, cek_oid_len,
 221                                acvp, acvp_len,
 222                                partyu, partyu_len, partyv, partyv_len,
 223                                supp_pub, supp_pub_len, supp_priv, supp_priv_len,
 224                                keylen_bits, NULL)
 225         || !WPACKET_get_total_written(&pkt, &der_buflen))
 226         goto err;
 227     WPACKET_cleanup(&pkt);
 228     /* Alloc the buffer */
 229     der_buf = OPENSSL_zalloc(der_buflen);
 230     if (der_buf == NULL)
 231         goto err;
 232     /* Encode into the buffer */
 233     if (!der_encode_sharedinfo(&pkt, der_buf, der_buflen, cek_oid, cek_oid_len,
 234                                acvp, acvp_len,
 235                                partyu, partyu_len, partyv, partyv_len,
 236                                supp_pub, supp_pub_len, supp_priv, supp_priv_len,
 237                                keylen_bits, &pcounter))
 238         goto err;
 239     /*
 240      * Since we allocated the exact size required, the buffer should point to the
 241      * start of the alllocated buffer at this point.
 242      */
 243     if (WPACKET_get_curr(&pkt) != der_buf)
 244         goto err;
 245
 246     /*
 247      * The data for the DER encoded octet string of a 32 bit counter = 1
 248      * should be 04 04 00 00 00 01
 249      * So just check the header is correct and skip over it.
 250      * This counter will be incremented in the kdf update loop.
 251      */
 252     if (pcounter == NULL
 253         || pcounter[0] != 0x04
 254         || pcounter[1] != 0x04)
 255         goto err;
 256     *out_ctr = (pcounter + 2);
 257     *der = der_buf;
 258     *der_len = der_buflen;
 259     ret = 1;
 260 err:
 261     WPACKET_cleanup(&pkt);
 262     return ret;
 263 }
 264
 265 static int x942kdf_hash_kdm(const EVP_MD *kdf_md,
 266                             const unsigned char *z, size_t z_len,
 267                             const unsigned char *other, size_t other_len,
 268                             unsigned char *ctr,
 269                             unsigned char *derived_key, size_t derived_key_len)
 270 {
 271     int ret = 0, hlen;
 272     size_t counter, out_len, len = derived_key_len;
 273     unsigned char mac[EVP_MAX_MD_SIZE];
 274     unsigned char *out = derived_key;
 275     EVP_MD_CTX *ctx = NULL, *ctx_init = NULL;
 276
 277     if (z_len > X942KDF_MAX_INLEN
 278         || other_len > X942KDF_MAX_INLEN
 279         || derived_key_len > X942KDF_MAX_INLEN
 280         || derived_key_len == 0) {
 281         ERR_raise(ERR_LIB_PROV, PROV_R_BAD_LENGTH);
 282         return 0;
 283     }
 284
 285     hlen = EVP_MD_get_size(kdf_md);
 286     if (hlen <= 0)
 287         return 0;
 288     out_len = (size_t)hlen;
 289
 290     ctx = EVP_MD_CTX_create();
 291     ctx_init = EVP_MD_CTX_create();
 292     if (ctx == NULL || ctx_init == NULL)
 293         goto end;
 294
 295     if (!EVP_DigestInit(ctx_init, kdf_md))
 296         goto end;
 297
 298     for (counter = 1;; counter++) {
 299         /* updating the ctr modifies 4 bytes in the 'other' buffer */
 300         ctr[0] = (unsigned char)((counter >> 24) & 0xff);
 301         ctr[1] = (unsigned char)((counter >> 16) & 0xff);
 302         ctr[2] = (unsigned char)((counter >> 8) & 0xff);
 303         ctr[3] = (unsigned char)(counter & 0xff);
 304
 305         if (!EVP_MD_CTX_copy_ex(ctx, ctx_init)
 306             || !EVP_DigestUpdate(ctx, z, z_len)
 307             || !EVP_DigestUpdate(ctx, other, other_len))
 308             goto end;
 309         if (len >= out_len) {
 310             if (!EVP_DigestFinal_ex(ctx, out, NULL))
 311                 goto end;
 312             out += out_len;
 313             len -= out_len;
 314             if (len == 0)
 315                 break;
 316         } else {
 317             if (!EVP_DigestFinal_ex(ctx, mac, NULL))
 318                 goto end;
 319             memcpy(out, mac, len);
 320             break;
 321         }
 322     }
 323     ret = 1;
 324 end:
 325     EVP_MD_CTX_free(ctx);
 326     EVP_MD_CTX_free(ctx_init);
 327     OPENSSL_cleanse(mac, sizeof(mac));
 328     return ret;
 329 }
 330
 331 static void *x942kdf_new(void *provctx)
 332 {
 333     KDF_X942 *ctx;
 334
 335     if (!ossl_prov_is_running())
 336         return 0;
 337
 338     if ((ctx = OPENSSL_zalloc(sizeof(*ctx))) == NULL)
 339         ERR_raise(ERR_LIB_PROV, ERR_R_MALLOC_FAILURE);
 340     ctx->provctx = provctx;
 341     ctx->use_keybits = 1;
 342     return ctx;
 343 }
 344
 345 static void x942kdf_reset(void *vctx)
 346 {
 347     KDF_X942 *ctx = (KDF_X942 *)vctx;
 348     void *provctx = ctx->provctx;
 349
 350     ossl_prov_digest_reset(&ctx->digest);
 351     OPENSSL_clear_free(ctx->secret, ctx->secret_len);
 352     OPENSSL_clear_free(ctx->acvpinfo, ctx->acvpinfo_len);
 353     OPENSSL_clear_free(ctx->partyuinfo, ctx->partyuinfo_len);
 354     OPENSSL_clear_free(ctx->partyvinfo, ctx->partyvinfo_len);
 355     OPENSSL_clear_free(ctx->supp_pubinfo, ctx->supp_pubinfo_len);
 356     OPENSSL_clear_free(ctx->supp_privinfo, ctx->supp_privinfo_len);
 357     memset(ctx, 0, sizeof(*ctx));
 358     ctx->provctx = provctx;
 359     ctx->use_keybits = 1;
 360 }
 361
 362 static void x942kdf_free(void *vctx)
 363 {
 364     KDF_X942 *ctx = (KDF_X942 *)vctx;
 365
 366     if (ctx != NULL) {
 367         x942kdf_reset(ctx);
 368         OPENSSL_free(ctx);
 369     }
 370 }
 371
 372 static void *x942kdf_dup(void *vctx)
 373 {
 374     const KDF_X942 *src = (const KDF_X942 *)vctx;
 375     KDF_X942 *dest;
 376
 377     dest = x942kdf_new(src->provctx);
 378     if (dest != NULL) {
 379         if (!ossl_prov_memdup(src->secret, src->secret_len,
 380                               &dest->secret , &dest->secret_len)
 381                 || !ossl_prov_memdup(src->acvpinfo, src->acvpinfo_len,
 382                                      &dest->acvpinfo , &dest->acvpinfo_len)
 383                 || !ossl_prov_memdup(src->partyuinfo, src->partyuinfo_len,
 384                                      &dest->partyuinfo , &dest->partyuinfo_len)
 385                 || !ossl_prov_memdup(src->partyvinfo, src->partyvinfo_len,
 386                                      &dest->partyvinfo , &dest->partyvinfo_len)
 387                 || !ossl_prov_memdup(src->supp_pubinfo, src->supp_pubinfo_len,
 388                                      &dest->supp_pubinfo,
 389                                      &dest->supp_pubinfo_len)
 390                 || !ossl_prov_memdup(src->supp_privinfo, src->supp_privinfo_len,
 391                                      &dest->supp_privinfo,
 392                                      &dest->supp_privinfo_len)
 393                 || !ossl_prov_digest_copy(&dest->digest, &src->digest))
 394             goto err;
 395         dest->cek_oid = src->cek_oid;
 396         dest->cek_oid_len = src->cek_oid_len;
 397         dest->dkm_len = src->dkm_len;
 398         dest->use_keybits = src->use_keybits;
 399     }
 400     return dest;
 401
 402  err:
 403     x942kdf_free(dest);
 404     return NULL;
 405 }
 406
 407 static int x942kdf_set_buffer(unsigned char **out, size_t *out_len,
 408                               const OSSL_PARAM *p)
 409 {
 410     if (p->data_size == 0 || p->data == NULL)
 411         return 1;
 412
 413     OPENSSL_free(*out);
 414     *out = NULL;
 415     return OSSL_PARAM_get_octet_string(p, (void **)out, 0, out_len);
 416 }
 417
 418 static size_t x942kdf_size(KDF_X942 *ctx)
 419 {
 420     int len;
 421     const EVP_MD *md = ossl_prov_digest_md(&ctx->digest);
 422
 423     if (md == NULL) {
 424         ERR_raise(ERR_LIB_PROV, PROV_R_MISSING_MESSAGE_DIGEST);
 425         return 0;
 426     }
 427     len = EVP_MD_get_size(md);
 428     return (len <= 0) ? 0 : (size_t)len;
 429 }
 430
 431 static int x942kdf_derive(void *vctx, unsigned char *key, size_t keylen,
 432                           const OSSL_PARAM params[])
 433 {
 434     KDF_X942 *ctx = (KDF_X942 *)vctx;
 435     const EVP_MD *md;
 436     int ret = 0;
 437     unsigned char *ctr;
 438     unsigned char *der = NULL;
 439     size_t der_len = 0;
 440
 441     if (!ossl_prov_is_running() || !x942kdf_set_ctx_params(ctx, params))
 442         return 0;
 443
 444     /*
 445      * These 2 options encode to the same field so only one of them should be
 446      * active at once.
 447      */
 448     if (ctx->use_keybits && ctx->supp_pubinfo != NULL) {
 449         ERR_raise(ERR_LIB_PROV, PROV_R_INVALID_PUBINFO);
 450         return 0;
 451     }
 452     /*
 453      * If the blob of acvp data is used then the individual info fields that it
 454      * replaces should not also be defined.
 455      */
 456     if (ctx->acvpinfo != NULL
 457         && (ctx->partyuinfo != NULL
 458             || ctx->partyvinfo != NULL
 459             || ctx->supp_pubinfo != NULL
 460             || ctx->supp_privinfo != NULL)) {
 461         ERR_raise(ERR_LIB_PROV, PROV_R_INVALID_DATA);
 462         return 0;
 463     }
 464     if (ctx->secret == NULL) {
 465         ERR_raise(ERR_LIB_PROV, PROV_R_MISSING_SECRET);
 466         return 0;
 467     }
 468     md = ossl_prov_digest_md(&ctx->digest);
 469     if (md == NULL) {
 470         ERR_raise(ERR_LIB_PROV, PROV_R_MISSING_MESSAGE_DIGEST);
 471         return 0;
 472     }
 473     if (ctx->cek_oid == NULL || ctx->cek_oid_len == 0) {
 474         ERR_raise(ERR_LIB_PROV, PROV_R_MISSING_CEK_ALG);
 475         return 0;
 476     }
 477     if (ctx->partyuinfo != NULL && ctx->partyuinfo_len >= X942KDF_MAX_INLEN) {
 478         /*
 479          * Note the ukm length MUST be 512 bits if it is used.
 480          * For backwards compatibility the old check is being done.
 481          */
 482         ERR_raise(ERR_LIB_PROV, PROV_R_INVALID_UKM_LENGTH);
 483         return 0;
 484     }
 485     /* generate the otherinfo der */
 486     if (!x942_encode_otherinfo(ctx->use_keybits ? ctx->dkm_len : 0,
 487                                ctx->cek_oid, ctx->cek_oid_len,
 488                                ctx->acvpinfo, ctx->acvpinfo_len,
 489                                ctx->partyuinfo, ctx->partyuinfo_len,
 490                                ctx->partyvinfo, ctx->partyvinfo_len,
 491                                ctx->supp_pubinfo, ctx->supp_pubinfo_len,
 492                                ctx->supp_privinfo, ctx->supp_privinfo_len,
 493                                &der, &der_len, &ctr)) {
 494         ERR_raise(ERR_LIB_PROV, PROV_R_BAD_ENCODING);
 495         return 0;
 496     }
 497     ret = x942kdf_hash_kdm(md, ctx->secret, ctx->secret_len,
 498                            der, der_len, ctr, key, keylen);
 499     OPENSSL_free(der);
 500     return ret;
 501 }
 502
 503 static int x942kdf_set_ctx_params(void *vctx, const OSSL_PARAM params[])
 504 {
 505     const OSSL_PARAM *p, *pq;
 506     KDF_X942 *ctx = vctx;
 507     OSSL_LIB_CTX *provctx = PROV_LIBCTX_OF(ctx->provctx);
 508     const char *propq = NULL;
 509     size_t id;
 510
 511     if (params == NULL)
 512         return 1;
 513     if (!ossl_prov_digest_load_from_params(&ctx->digest, params, provctx))
 514         return 0;
 515
 516     p = OSSL_PARAM_locate_const(params, OSSL_KDF_PARAM_SECRET);
 517     if (p == NULL)
 518         p = OSSL_PARAM_locate_const(params, OSSL_KDF_PARAM_KEY);
 519     if (p != NULL && !x942kdf_set_buffer(&ctx->secret, &ctx->secret_len, p))
 520         return 0;
 521
 522     p = OSSL_PARAM_locate_const(params, OSSL_KDF_PARAM_X942_ACVPINFO);
 523     if (p != NULL
 524         && !x942kdf_set_buffer(&ctx->acvpinfo, &ctx->acvpinfo_len, p))
 525         return 0;
 526
 527     p = OSSL_PARAM_locate_const(params, OSSL_KDF_PARAM_X942_PARTYUINFO);
 528     if (p == NULL)
 529         p = OSSL_PARAM_locate_const(params, OSSL_KDF_PARAM_UKM);
 530     if (p != NULL
 531         && !x942kdf_set_buffer(&ctx->partyuinfo, &ctx->partyuinfo_len, p))
 532         return 0;
 533
 534     p = OSSL_PARAM_locate_const(params, OSSL_KDF_PARAM_X942_PARTYVINFO);
 535     if (p != NULL
 536         && !x942kdf_set_buffer(&ctx->partyvinfo, &ctx->partyvinfo_len, p))
 537         return 0;
 538
 539     p = OSSL_PARAM_locate_const(params, OSSL_KDF_PARAM_X942_USE_KEYBITS);
 540     if (p != NULL && !OSSL_PARAM_get_int(p, &ctx->use_keybits))
 541         return 0;
 542
 543     p = OSSL_PARAM_locate_const(params, OSSL_KDF_PARAM_X942_SUPP_PUBINFO);
 544     if (p != NULL) {
 545         if (!x942kdf_set_buffer(&ctx->supp_pubinfo, &ctx->supp_pubinfo_len, p))
 546             return 0;
 547         ctx->use_keybits = 0;
 548     }
 549
 550     p = OSSL_PARAM_locate_const(params, OSSL_KDF_PARAM_X942_SUPP_PRIVINFO);
 551     if (p != NULL
 552         && !x942kdf_set_buffer(&ctx->supp_privinfo, &ctx->supp_privinfo_len, p))
 553         return 0;
 554
 555     p = OSSL_PARAM_locate_const(params, OSSL_KDF_PARAM_CEK_ALG);
 556     if (p != NULL) {
 557         if (p->data_type != OSSL_PARAM_UTF8_STRING)
 558             return 0;
 559         pq = OSSL_PARAM_locate_const(params, OSSL_ALG_PARAM_PROPERTIES);
 560         /*
 561          * We already grab the properties during ossl_prov_digest_load_from_params()
 562          * so there is no need to check the validity again..
 563          */
 564         if (pq != NULL)
 565             propq = p->data;
 566         if (find_alg_id(provctx, p->data, propq, &id) == 0)
 567             return 0;
 568         ctx->cek_oid = kek_algs[id].oid;
 569         ctx->cek_oid_len = kek_algs[id].oid_len;
 570         ctx->dkm_len = kek_algs[id].keklen;
 571     }
 572     return 1;
 573 }
 574
 575 static const OSSL_PARAM *x942kdf_settable_ctx_params(ossl_unused void *ctx,
 576                                                      ossl_unused void *provctx)
 577 {
 578     static const OSSL_PARAM known_settable_ctx_params[] = {
 579         OSSL_PARAM_utf8_string(OSSL_KDF_PARAM_PROPERTIES, NULL, 0),
 580         OSSL_PARAM_utf8_string(OSSL_KDF_PARAM_DIGEST, NULL, 0),
 581         OSSL_PARAM_octet_string(OSSL_KDF_PARAM_SECRET, NULL, 0),
 582         OSSL_PARAM_octet_string(OSSL_KDF_PARAM_KEY, NULL, 0),
 583         OSSL_PARAM_octet_string(OSSL_KDF_PARAM_UKM, NULL, 0),
 584         OSSL_PARAM_octet_string(OSSL_KDF_PARAM_X942_ACVPINFO, NULL, 0),
 585         OSSL_PARAM_octet_string(OSSL_KDF_PARAM_X942_PARTYUINFO, NULL, 0),
 586         OSSL_PARAM_octet_string(OSSL_KDF_PARAM_X942_PARTYVINFO, NULL, 0),
 587         OSSL_PARAM_octet_string(OSSL_KDF_PARAM_X942_SUPP_PUBINFO, NULL, 0),
 588         OSSL_PARAM_octet_string(OSSL_KDF_PARAM_X942_SUPP_PRIVINFO, NULL, 0),
 589         OSSL_PARAM_int(OSSL_KDF_PARAM_X942_USE_KEYBITS, NULL),
 590         OSSL_PARAM_utf8_string(OSSL_KDF_PARAM_CEK_ALG, NULL, 0),
 591         OSSL_PARAM_END
 592     };
 593     return known_settable_ctx_params;
 594 }
 595
 596 static int x942kdf_get_ctx_params(void *vctx, OSSL_PARAM params[])
 597 {
 598     KDF_X942 *ctx = (KDF_X942 *)vctx;
 599     OSSL_PARAM *p;
 600
 601     if ((p = OSSL_PARAM_locate(params, OSSL_KDF_PARAM_SIZE)) != NULL)
 602         return OSSL_PARAM_set_size_t(p, x942kdf_size(ctx));
 603     return -2;
 604 }
 605
 606 static const OSSL_PARAM *x942kdf_gettable_ctx_params(ossl_unused void *ctx,
 607                                                      ossl_unused void *provctx)
 608 {
 609     static const OSSL_PARAM known_gettable_ctx_params[] = {
 610         OSSL_PARAM_size_t(OSSL_KDF_PARAM_SIZE, NULL),
 611         OSSL_PARAM_END
 612     };
 613     return known_gettable_ctx_params;
 614 }
 615
 616 const OSSL_DISPATCH ossl_kdf_x942_kdf_functions[] = {
 617     { OSSL_FUNC_KDF_NEWCTX, (void(*)(void))x942kdf_new },
 618     { OSSL_FUNC_KDF_DUPCTX, (void(*)(void))x942kdf_dup },
 619     { OSSL_FUNC_KDF_FREECTX, (void(*)(void))x942kdf_free },
 620     { OSSL_FUNC_KDF_RESET, (void(*)(void))x942kdf_reset },
 621     { OSSL_FUNC_KDF_DERIVE, (void(*)(void))x942kdf_derive },
 622     { OSSL_FUNC_KDF_SETTABLE_CTX_PARAMS,
 623       (void(*)(void))x942kdf_settable_ctx_params },
 624     { OSSL_FUNC_KDF_SET_CTX_PARAMS, (void(*)(void))x942kdf_set_ctx_params },
 625     { OSSL_FUNC_KDF_GETTABLE_CTX_PARAMS,
 626       (void(*)(void))x942kdf_gettable_ctx_params },
 627     { OSSL_FUNC_KDF_GET_CTX_PARAMS, (void(*)(void))x942kdf_get_ctx_params },
 628     { 0, NULL }
 629 };