crypto/dh/dh_kdf.c

   1 /*
   2  * Copyright 2013-2020 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  * DH low level APIs are deprecated for public use, but still ok for
  12  * internal use.
  13  */
  14 #include "internal/deprecated.h"
  15
  16 #include "e_os.h"
  17 #include "e_os.h"
  18 #include <string.h>
  19 #include <openssl/core_names.h>
  20 #include <openssl/dh.h>
  21 #include <openssl/evp.h>
  22 #include <openssl/asn1.h>
  23 #include <openssl/kdf.h>
  24 #include <internal/provider.h>
  25 #include <crypto/dh.h>
  26
  27 /* Key derivation function from X9.63/SECG */
  28 int dh_KDF_X9_42_asn1(unsigned char *out, size_t outlen,
  29                       const unsigned char *Z, size_t Zlen,
  30                       const char *cek_alg,
  31                       const unsigned char *ukm, size_t ukmlen, const EVP_MD *md,
  32                       OSSL_LIB_CTX *libctx, const char *propq)
  33 {
  34     int ret = 0;
  35     EVP_KDF_CTX *kctx = NULL;
  36     EVP_KDF *kdf = NULL;
  37     OSSL_PARAM params[5], *p = params;
  38     const char *mdname = EVP_MD_name(md);
  39
  40     kdf = EVP_KDF_fetch(libctx, OSSL_KDF_NAME_X942KDF, propq);
  41     kctx = EVP_KDF_CTX_new(kdf);
  42     if (kctx == NULL)
  43         goto err;
  44
  45     *p++ = OSSL_PARAM_construct_utf8_string(OSSL_KDF_PARAM_DIGEST,
  46                                             (char *)mdname, 0);
  47     *p++ = OSSL_PARAM_construct_octet_string(OSSL_KDF_PARAM_KEY,
  48                                              (unsigned char *)Z, Zlen);
  49     if (ukm != NULL)
  50         *p++ = OSSL_PARAM_construct_octet_string(OSSL_KDF_PARAM_UKM,
  51                                                  (unsigned char *)ukm, ukmlen);
  52     *p++ = OSSL_PARAM_construct_utf8_string(OSSL_KDF_PARAM_CEK_ALG,
  53                                             (char *)cek_alg, 0);
  54     *p = OSSL_PARAM_construct_end();
  55     ret = EVP_KDF_CTX_set_params(kctx, params) > 0
  56           && EVP_KDF_derive(kctx, out, outlen) > 0;
  57 err:
  58     EVP_KDF_CTX_free(kctx);
  59     EVP_KDF_free(kdf);
  60     return ret;
  61 }
  62
  63 #if !defined(FIPS_MODULE)
  64 int DH_KDF_X9_42(unsigned char *out, size_t outlen,
  65                  const unsigned char *Z, size_t Zlen,
  66                  ASN1_OBJECT *key_oid,
  67                  const unsigned char *ukm, size_t ukmlen, const EVP_MD *md)
  68 {
  69     int nid;
  70     const char *key_alg = NULL;
  71     const OSSL_PROVIDER *prov = EVP_MD_provider(md);
  72     OSSL_LIB_CTX *libctx = ossl_provider_library_context(prov);
  73
  74     nid = OBJ_obj2nid(key_oid);
  75     if (nid == NID_undef)
  76         return 0;
  77     key_alg = OBJ_nid2sn(nid);
  78     if (key_alg == NULL)
  79         return 0;
  80
  81     return dh_KDF_X9_42_asn1(out, outlen, Z, Zlen, key_alg,
  82                              ukm, ukmlen, md, libctx, NULL);
  83 }
  84 #endif /* !defined(FIPS_MODULE) */