dsa_lib.c revision 59191
1/* crypto/dsa/dsa_lib.c */
2/* Copyright (C) 1995-1998 Eric Young (eay@cryptsoft.com)
3 * All rights reserved.
4 *
5 * This package is an SSL implementation written
6 * by Eric Young (eay@cryptsoft.com).
7 * The implementation was written so as to conform with Netscapes SSL.
8 *
9 * This library is free for commercial and non-commercial use as long as
10 * the following conditions are aheared to.  The following conditions
11 * apply to all code found in this distribution, be it the RC4, RSA,
12 * lhash, DES, etc., code; not just the SSL code.  The SSL documentation
13 * included with this distribution is covered by the same copyright terms
14 * except that the holder is Tim Hudson (tjh@cryptsoft.com).
15 *
16 * Copyright remains Eric Young's, and as such any Copyright notices in
17 * the code are not to be removed.
18 * If this package is used in a product, Eric Young should be given attribution
19 * as the author of the parts of the library used.
20 * This can be in the form of a textual message at program startup or
21 * in documentation (online or textual) provided with the package.
22 *
23 * Redistribution and use in source and binary forms, with or without
24 * modification, are permitted provided that the following conditions
25 * are met:
26 * 1. Redistributions of source code must retain the copyright
27 *    notice, this list of conditions and the following disclaimer.
28 * 2. Redistributions in binary form must reproduce the above copyright
29 *    notice, this list of conditions and the following disclaimer in the
30 *    documentation and/or other materials provided with the distribution.
31 * 3. All advertising materials mentioning features or use of this software
32 *    must display the following acknowledgement:
33 *    "This product includes cryptographic software written by
34 *     Eric Young (eay@cryptsoft.com)"
35 *    The word 'cryptographic' can be left out if the rouines from the library
36 *    being used are not cryptographic related :-).
37 * 4. If you include any Windows specific code (or a derivative thereof) from
38 *    the apps directory (application code) you must include an acknowledgement:
39 *    "This product includes software written by Tim Hudson (tjh@cryptsoft.com)"
40 *
41 * THIS SOFTWARE IS PROVIDED BY ERIC YOUNG ``AS IS'' AND
42 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
43 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
44 * ARE DISCLAIMED.  IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE
45 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
46 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
47 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
48 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
49 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
50 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
51 * SUCH DAMAGE.
52 *
53 * The licence and distribution terms for any publically available version or
54 * derivative of this code cannot be changed.  i.e. this code cannot simply be
55 * copied and put under another distribution licence
56 * [including the GNU Public Licence.]
57 */
58
59/* Original version from Steven Schoch <schoch@sheba.arc.nasa.gov> */
60
61#include <stdio.h>
62#include "cryptlib.h"
63#include <openssl/bn.h>
64#include <openssl/dsa.h>
65#include <openssl/asn1.h>
66
67const char *DSA_version="DSA" OPENSSL_VERSION_PTEXT;
68
69static DSA_METHOD *default_DSA_method;
70static int dsa_meth_num = 0;
71static STACK_OF(CRYPTO_EX_DATA_FUNCS) *dsa_meth = NULL;
72
73void DSA_set_default_method(DSA_METHOD *meth)
74{
75	default_DSA_method = meth;
76}
77
78DSA_METHOD *DSA_get_default_method(void)
79{
80	if(!default_DSA_method) default_DSA_method = DSA_OpenSSL();
81	return default_DSA_method;
82}
83
84DSA *DSA_new(void)
85{
86	return DSA_new_method(NULL);
87}
88
89DSA_METHOD *DSA_set_method(DSA *dsa, DSA_METHOD *meth)
90{
91        DSA_METHOD *mtmp;
92        mtmp = dsa->meth;
93        if (mtmp->finish) mtmp->finish(dsa);
94        dsa->meth = meth;
95        if (meth->init) meth->init(dsa);
96        return mtmp;
97}
98
99
100DSA *DSA_new_method(DSA_METHOD *meth)
101	{
102	DSA *ret;
103
104	ret=(DSA *)Malloc(sizeof(DSA));
105	if (ret == NULL)
106		{
107		DSAerr(DSA_F_DSA_NEW,ERR_R_MALLOC_FAILURE);
108		return(NULL);
109		}
110	if(!default_DSA_method) default_DSA_method = DSA_OpenSSL();
111	if(meth) ret->meth = meth;
112	else ret->meth = default_DSA_method;
113	ret->pad=0;
114	ret->version=0;
115	ret->write_params=1;
116	ret->p=NULL;
117	ret->q=NULL;
118	ret->g=NULL;
119
120	ret->pub_key=NULL;
121	ret->priv_key=NULL;
122
123	ret->kinv=NULL;
124	ret->r=NULL;
125	ret->method_mont_p=NULL;
126
127	ret->references=1;
128	ret->flags=ret->meth->flags;
129	if ((ret->meth->init != NULL) && !ret->meth->init(ret))
130		{
131		Free(ret);
132		ret=NULL;
133		}
134	else
135		CRYPTO_new_ex_data(dsa_meth,ret,&ret->ex_data);
136
137	return(ret);
138	}
139
140void DSA_free(DSA *r)
141	{
142	int i;
143
144	if (r == NULL) return;
145
146	i=CRYPTO_add(&r->references,-1,CRYPTO_LOCK_DSA);
147#ifdef REF_PRINT
148	REF_PRINT("DSA",r);
149#endif
150	if (i > 0) return;
151#ifdef REF_CHECK
152	if (i < 0)
153		{
154		fprintf(stderr,"DSA_free, bad reference count\n");
155		abort();
156		}
157#endif
158
159	CRYPTO_free_ex_data(dsa_meth, r, &r->ex_data);
160
161	if(r->meth->finish) r->meth->finish(r);
162
163	if (r->p != NULL) BN_clear_free(r->p);
164	if (r->q != NULL) BN_clear_free(r->q);
165	if (r->g != NULL) BN_clear_free(r->g);
166	if (r->pub_key != NULL) BN_clear_free(r->pub_key);
167	if (r->priv_key != NULL) BN_clear_free(r->priv_key);
168	if (r->kinv != NULL) BN_clear_free(r->kinv);
169	if (r->r != NULL) BN_clear_free(r->r);
170	Free(r);
171	}
172
173int DSA_size(DSA *r)
174	{
175	int ret,i;
176	ASN1_INTEGER bs;
177	unsigned char buf[4];
178
179	i=BN_num_bits(r->q);
180	bs.length=(i+7)/8;
181	bs.data=buf;
182	bs.type=V_ASN1_INTEGER;
183	/* If the top bit is set the asn1 encoding is 1 larger. */
184	buf[0]=0xff;
185
186	i=i2d_ASN1_INTEGER(&bs,NULL);
187	i+=i; /* r and s */
188	ret=ASN1_object_size(1,i,V_ASN1_SEQUENCE);
189	return(ret);
190	}
191
192int DSA_get_ex_new_index(long argl, void *argp, CRYPTO_EX_new *new_func,
193	     CRYPTO_EX_dup *dup_func, CRYPTO_EX_free *free_func)
194        {
195	dsa_meth_num++;
196	return(CRYPTO_get_ex_new_index(dsa_meth_num-1,
197		&dsa_meth,argl,argp,new_func,dup_func,free_func));
198        }
199
200int DSA_set_ex_data(DSA *d, int idx, void *arg)
201	{
202	return(CRYPTO_set_ex_data(&d->ex_data,idx,arg));
203	}
204
205void *DSA_get_ex_data(DSA *d, int idx)
206	{
207	return(CRYPTO_get_ex_data(&d->ex_data,idx));
208	}
209
210#ifndef NO_DH
211DH *DSA_dup_DH(DSA *r)
212	{
213	/* DSA has p, q, g, optional pub_key, optional priv_key.
214	 * DH has p, optional length, g, optional pub_key, optional priv_key.
215	 */
216
217	DH *ret = NULL;
218
219	if (r == NULL)
220		goto err;
221	ret = DH_new();
222	if (ret == NULL)
223		goto err;
224	if (r->p != NULL)
225		if ((ret->p = BN_dup(r->p)) == NULL)
226			goto err;
227	if (r->q != NULL)
228		ret->length = BN_num_bits(r->q);
229	if (r->g != NULL)
230		if ((ret->g = BN_dup(r->g)) == NULL)
231			goto err;
232	if (r->pub_key != NULL)
233		if ((ret->pub_key = BN_dup(r->pub_key)) == NULL)
234			goto err;
235	if (r->priv_key != NULL)
236		if ((ret->priv_key = BN_dup(r->priv_key)) == NULL)
237			goto err;
238
239	return ret;
240
241 err:
242	if (ret != NULL)
243		DH_free(ret);
244	return NULL;
245	}
246#endif
247