crypto/dh/dh_kdf.c

   1 /*
   2  * Copyright 2013-2021 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 /*
  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 "internal/e_os.h"
  17 #include "internal/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 ossl_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,
  32                            const EVP_MD *md,
  33                            OSSL_LIB_CTX *libctx, const char *propq)
  34 {
  35     int ret = 0;
  36     EVP_KDF_CTX *kctx = NULL;
  37     EVP_KDF *kdf = NULL;
  38     OSSL_PARAM params[5], *p = params;
  39     const char *mdname = EVP_MD_get0_name(md);
  40
  41     kdf = EVP_KDF_fetch(libctx, OSSL_KDF_NAME_X942KDF_ASN1, propq);
  42     kctx = EVP_KDF_CTX_new(kdf);
  43     if (kctx == NULL)
  44         goto err;
  45
  46     *p++ = OSSL_PARAM_construct_utf8_string(OSSL_KDF_PARAM_DIGEST,
  47                                             (char *)mdname, 0);
  48     *p++ = OSSL_PARAM_construct_octet_string(OSSL_KDF_PARAM_KEY,
  49                                              (unsigned char *)Z, Zlen);
  50     if (ukm != NULL)
  51         *p++ = OSSL_PARAM_construct_octet_string(OSSL_KDF_PARAM_UKM,
  52                                                  (unsigned char *)ukm, ukmlen);
  53     *p++ = OSSL_PARAM_construct_utf8_string(OSSL_KDF_PARAM_CEK_ALG,
  54                                             (char *)cek_alg, 0);
  55     *p = OSSL_PARAM_construct_end();
  56     ret = EVP_KDF_derive(kctx, out, outlen, params) > 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     char key_alg[OSSL_MAX_NAME_SIZE];
  70     const OSSL_PROVIDER *prov = EVP_MD_get0_provider(md);
  71     OSSL_LIB_CTX *libctx = ossl_provider_libctx(prov);
  72
  73     if (OBJ_obj2txt(key_alg, sizeof(key_alg), key_oid, 0) <= 0)
  74         return 0;
  75
  76     return ossl_dh_kdf_X9_42_asn1(out, outlen, Z, Zlen, key_alg,
  77                                   ukm, ukmlen, md, libctx, NULL);
  78 }
  79 #endif /* !defined(FIPS_MODULE) */