demos/pkey/EVP_PKEY_DSA_paramfromdata.c

   1 /*-
   2  * Copyright 2022-2023 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  * Example showing how to load DSA params from raw data
  12  * using EVP_PKEY_fromdata()
  13  */
  14
  15 #include <openssl/param_build.h>
  16 #include <openssl/evp.h>
  17 #include <openssl/core_names.h>
  18 #include "dsa.inc"
  19
  20 int main(int argc, char **argv)
  21 {
  22     int ret = EXIT_FAILURE;
  23     OSSL_LIB_CTX *libctx = NULL;
  24     const char *propq = NULL;
  25     EVP_PKEY_CTX *ctx = NULL;
  26     EVP_PKEY *dsaparamkey = NULL;
  27     OSSL_PARAM_BLD *bld = NULL;
  28     OSSL_PARAM *params = NULL;
  29     BIGNUM *p = NULL, *q = NULL, *g = NULL;
  30
  31     p = BN_bin2bn(dsa_p, sizeof(dsa_p), NULL);
  32     q = BN_bin2bn(dsa_q, sizeof(dsa_q), NULL);
  33     g = BN_bin2bn(dsa_g, sizeof(dsa_g), NULL);
  34     if (p == NULL || q == NULL || g == NULL)
  35         goto cleanup;
  36
  37     /* Use OSSL_PARAM_BLD if you need to handle BIGNUM Parameters */
  38     bld = OSSL_PARAM_BLD_new();
  39     if (bld == NULL)
  40         goto cleanup;
  41     if (!OSSL_PARAM_BLD_push_BN(bld, OSSL_PKEY_PARAM_FFC_P, p)
  42             || !OSSL_PARAM_BLD_push_BN(bld, OSSL_PKEY_PARAM_FFC_Q, q)
  43             || !OSSL_PARAM_BLD_push_BN(bld, OSSL_PKEY_PARAM_FFC_G, g))
  44         goto cleanup;
  45     params = OSSL_PARAM_BLD_to_param(bld);
  46     if (params == NULL)
  47         goto cleanup;
  48
  49     ctx = EVP_PKEY_CTX_new_from_name(libctx, "DSA", propq);
  50     if (ctx == NULL) {
  51         fprintf(stderr, "EVP_PKEY_CTX_new_from_name() failed\n");
  52         goto cleanup;
  53     }
  54
  55     if (EVP_PKEY_fromdata_init(ctx) <= 0
  56             || EVP_PKEY_fromdata(ctx, &dsaparamkey, EVP_PKEY_KEY_PARAMETERS, params) <= 0) {
  57         fprintf(stderr, "EVP_PKEY_fromdata() failed\n");
  58         goto cleanup;
  59     }
  60
  61     if (!dsa_print_key(dsaparamkey, 0, libctx, propq))
  62         goto cleanup;
  63
  64     ret = EXIT_SUCCESS;
  65 cleanup:
  66     EVP_PKEY_free(dsaparamkey);
  67     EVP_PKEY_CTX_free(ctx);
  68     OSSL_PARAM_free(params);
  69     OSSL_PARAM_BLD_free(bld);
  70     BN_free(g);
  71     BN_free(q);
  72     BN_free(p);
  73
  74     return ret;
  75 }