1 /*-
2 * Copyright 2022 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 generate DSA params using
12 * FIPS 186-4 DSA FFC parameter generation.
13 */
14
15 #include <openssl/evp.h>
16 #include "dsa.inc"
17
main(int argc,char ** argv)18 int main(int argc, char **argv)
19 {
20 int rv = EXIT_FAILURE;
21 OSSL_LIB_CTX *libctx = NULL;
22 const char *propq = NULL;
23 EVP_PKEY_CTX *ctx = NULL;
24 EVP_PKEY *dsaparamkey = NULL;
25 OSSL_PARAM params[7];
26 unsigned int pbits = 2048;
27 unsigned int qbits = 256;
28 int gindex = 42;
29
30 ctx = EVP_PKEY_CTX_new_from_name(libctx, "DSA", propq);
31 if (ctx == NULL)
32 goto cleanup;
33
34 /*
35 * Demonstrate how to set optional DSA fields as params.
36 * See doc/man7/EVP_PKEY-FFC.pod and doc/man7/EVP_PKEY-DSA.pod
37 * for more information.
38 */
39 params[0] = OSSL_PARAM_construct_utf8_string(OSSL_PKEY_PARAM_FFC_TYPE,
40 "fips186_4", 0);
41 params[1] = OSSL_PARAM_construct_uint(OSSL_PKEY_PARAM_FFC_PBITS, &pbits);
42 params[2] = OSSL_PARAM_construct_uint(OSSL_PKEY_PARAM_FFC_QBITS, &qbits);
43 params[3] = OSSL_PARAM_construct_int(OSSL_PKEY_PARAM_FFC_GINDEX, &gindex);
44 params[4] = OSSL_PARAM_construct_utf8_string(OSSL_PKEY_PARAM_FFC_DIGEST,
45 "SHA384", 0);
46 params[5] = OSSL_PARAM_construct_utf8_string(OSSL_PKEY_PARAM_FFC_DIGEST_PROPS,
47 "provider=default", 0);
48 params[6] = OSSL_PARAM_construct_end();
49
50 /* Generate a dsa param key using optional params */
51 if (EVP_PKEY_paramgen_init(ctx) <= 0
52 || EVP_PKEY_CTX_set_params(ctx, params) <= 0
53 || EVP_PKEY_paramgen(ctx, &dsaparamkey) <= 0) {
54 fprintf(stderr, "DSA paramgen failed\n");
55 goto cleanup;
56 }
57
58 if (!dsa_print_key(dsaparamkey, 0, libctx, propq))
59 goto cleanup;
60
61 rv = EXIT_SUCCESS;
62 cleanup:
63 EVP_PKEY_free(dsaparamkey);
64 EVP_PKEY_CTX_free(ctx);
65 return rv;
66 }
67