1 /* Copyright (C) 1995-1998 Eric Young (eay@cryptsoft.com)
4 * This package is an SSL implementation written
5 * by Eric Young (eay@cryptsoft.com).
6 * The implementation was written so as to conform with Netscapes SSL.
8 * This library is free for commercial and non-commercial use as long as
9 * the following conditions are aheared to. The following conditions
10 * apply to all code found in this distribution, be it the RC4, RSA,
11 * lhash, DES, etc., code; not just the SSL code. The SSL documentation
12 * included with this distribution is covered by the same copyright terms
13 * except that the holder is Tim Hudson (tjh@cryptsoft.com).
15 * Copyright remains Eric Young's, and as such any Copyright notices in
16 * the code are not to be removed.
17 * If this package is used in a product, Eric Young should be given attribution
18 * as the author of the parts of the library used.
19 * This can be in the form of a textual message at program startup or
20 * in documentation (online or textual) provided with the package.
22 * Redistribution and use in source and binary forms, with or without
23 * modification, are permitted provided that the following conditions
25 * 1. Redistributions of source code must retain the copyright
26 * notice, this list of conditions and the following disclaimer.
27 * 2. Redistributions in binary form must reproduce the above copyright
28 * notice, this list of conditions and the following disclaimer in the
29 * documentation and/or other materials provided with the distribution.
30 * 3. All advertising materials mentioning features or use of this software
31 * must display the following acknowledgement:
32 * "This product includes cryptographic software written by
33 * Eric Young (eay@cryptsoft.com)"
34 * The word 'cryptographic' can be left out if the rouines from the library
35 * being used are not cryptographic related :-).
36 * 4. If you include any Windows specific code (or a derivative thereof) from
37 * the apps directory (application code) you must include an acknowledgement:
38 * "This product includes software written by Tim Hudson (tjh@cryptsoft.com)"
40 * THIS SOFTWARE IS PROVIDED BY ERIC YOUNG ``AS IS'' AND
41 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
42 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
43 * ARE DISCLAIMED. IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE
44 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
45 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
46 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
47 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
48 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
49 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
52 * The licence and distribution terms for any publically available version or
53 * derivative of this code cannot be changed. i.e. this code cannot simply be
54 * copied and put under another distribution licence
55 * [including the GNU Public Licence.]
60 #include "internal/cryptlib.h"
61 #include <openssl/bn.h>
62 #include <openssl/dsa.h>
63 #include <openssl/rand.h>
65 static int dsa_builtin_keygen(DSA *dsa);
67 int DSA_generate_key(DSA *dsa)
69 if (dsa->meth->dsa_keygen)
70 return dsa->meth->dsa_keygen(dsa);
71 return dsa_builtin_keygen(dsa);
74 static int dsa_builtin_keygen(DSA *dsa)
78 BIGNUM *pub_key = NULL, *priv_key = NULL;
80 if ((ctx = BN_CTX_new()) == NULL)
83 if (dsa->priv_key == NULL) {
84 if ((priv_key = BN_secure_new()) == NULL)
87 priv_key = dsa->priv_key;
90 if (!BN_rand_range(priv_key, dsa->q))
92 while (BN_is_zero(priv_key)) ;
94 if (dsa->pub_key == NULL) {
95 if ((pub_key = BN_new()) == NULL)
98 pub_key = dsa->pub_key;
101 BIGNUM *local_prk = NULL;
104 if ((dsa->flags & DSA_FLAG_NO_EXP_CONSTTIME) == 0) {
105 local_prk = prk = BN_new();
106 if (local_prk == NULL)
108 BN_with_flags(prk, priv_key, BN_FLG_CONSTTIME);
113 if (!BN_mod_exp(pub_key, dsa->g, prk, dsa->p, ctx)) {
117 /* We MUST free local_prk before any further use of priv_key */
121 dsa->priv_key = priv_key;
122 dsa->pub_key = pub_key;
126 if (pub_key != dsa->pub_key)
128 if (priv_key != dsa->priv_key)