2 * Copyright 1995-2020 The OpenSSL Project Authors. All Rights Reserved.
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
11 * DSA low level APIs are deprecated for public use, but still ok for
14 #include "internal/deprecated.h"
18 #include "internal/cryptlib.h"
19 #include <openssl/bn.h>
20 #include <openssl/self_test.h>
21 #include "crypto/dsa.h"
22 #include "dsa_local.h"
25 # define MIN_STRENGTH 112
27 # define MIN_STRENGTH 80
30 static int dsa_keygen(DSA *dsa, int pairwise_test);
31 static int dsa_keygen_pairwise_test(DSA *dsa, OSSL_CALLBACK *cb, void *cbarg);
33 int DSA_generate_key(DSA *dsa)
36 if (dsa->meth->dsa_keygen != NULL)
37 return dsa->meth->dsa_keygen(dsa);
39 return dsa_keygen(dsa, 0);
42 int dsa_generate_public_key(BN_CTX *ctx, const DSA *dsa, const BIGNUM *priv_key,
46 BIGNUM *prk = BN_new();
50 BN_with_flags(prk, priv_key, BN_FLG_CONSTTIME);
52 /* pub_key = g ^ priv_key mod p */
53 if (!BN_mod_exp(pub_key, dsa->params.g, prk, dsa->params.p, ctx))
61 static int dsa_keygen(DSA *dsa, int pairwise_test)
65 BIGNUM *pub_key = NULL, *priv_key = NULL;
67 if ((ctx = BN_CTX_new_ex(dsa->libctx)) == NULL)
70 if (dsa->priv_key == NULL) {
71 if ((priv_key = BN_secure_new()) == NULL)
74 priv_key = dsa->priv_key;
78 * For FFC FIPS 186-4 keygen
79 * security strength s = 112,
80 * Max Private key size N = len(q)
82 if (!ffc_generate_private_key(ctx, &dsa->params, BN_num_bits(dsa->params.q),
83 MIN_STRENGTH, priv_key))
86 if (dsa->pub_key == NULL) {
87 if ((pub_key = BN_new()) == NULL)
90 pub_key = dsa->pub_key;
93 if (!dsa_generate_public_key(ctx, dsa, priv_key, pub_key))
96 dsa->priv_key = priv_key;
97 dsa->pub_key = pub_key;
101 #endif /* FIPS_MODE */
105 OSSL_CALLBACK *cb = NULL;
108 OSSL_SELF_TEST_get_callback(dsa->libctx, &cb, &cbarg);
109 ok = dsa_keygen_pairwise_test(dsa, cb, cbarg);
111 BN_free(dsa->pub_key);
112 BN_clear_free(dsa->priv_key);
120 if (pub_key != dsa->pub_key)
122 if (priv_key != dsa->priv_key)
130 * FIPS 140-2 IG 9.9 AS09.33
131 * Perform a sign/verify operation.
133 static int dsa_keygen_pairwise_test(DSA *dsa, OSSL_CALLBACK *cb, void *cbarg)
136 unsigned char dgst[16] = {0};
137 unsigned int dgst_len = (unsigned int)sizeof(dgst);
139 OSSL_SELF_TEST *st = NULL;
141 st = OSSL_SELF_TEST_new(cb, cbarg);
145 OSSL_SELF_TEST_onbegin(st, OSSL_SELF_TEST_TYPE_PCT,
146 OSSL_SELF_TEST_DESC_PCT_DSA);
148 sig = DSA_do_sign(dgst, (int)dgst_len, dsa);
152 OSSL_SELF_TEST_oncorrupt_byte(st, dgst);
154 if (DSA_do_verify(dgst, dgst_len, sig, dsa) != 1)
159 OSSL_SELF_TEST_onend(st, ret);
160 OSSL_SELF_TEST_free(st);