dsa_lib.c revision 55714
155714Skris/* crypto/dsa/dsa_lib.c */
255714Skris/* Copyright (C) 1995-1998 Eric Young (eay@cryptsoft.com)
355714Skris * All rights reserved.
455714Skris *
555714Skris * This package is an SSL implementation written
655714Skris * by Eric Young (eay@cryptsoft.com).
755714Skris * The implementation was written so as to conform with Netscapes SSL.
855714Skris *
955714Skris * This library is free for commercial and non-commercial use as long as
1055714Skris * the following conditions are aheared to.  The following conditions
1155714Skris * apply to all code found in this distribution, be it the RC4, RSA,
1255714Skris * lhash, DES, etc., code; not just the SSL code.  The SSL documentation
1355714Skris * included with this distribution is covered by the same copyright terms
1455714Skris * except that the holder is Tim Hudson (tjh@cryptsoft.com).
1555714Skris *
1655714Skris * Copyright remains Eric Young's, and as such any Copyright notices in
1755714Skris * the code are not to be removed.
1855714Skris * If this package is used in a product, Eric Young should be given attribution
1955714Skris * as the author of the parts of the library used.
2055714Skris * This can be in the form of a textual message at program startup or
2155714Skris * in documentation (online or textual) provided with the package.
2255714Skris *
2355714Skris * Redistribution and use in source and binary forms, with or without
2455714Skris * modification, are permitted provided that the following conditions
2555714Skris * are met:
2655714Skris * 1. Redistributions of source code must retain the copyright
2755714Skris *    notice, this list of conditions and the following disclaimer.
2855714Skris * 2. Redistributions in binary form must reproduce the above copyright
2955714Skris *    notice, this list of conditions and the following disclaimer in the
3055714Skris *    documentation and/or other materials provided with the distribution.
3155714Skris * 3. All advertising materials mentioning features or use of this software
3255714Skris *    must display the following acknowledgement:
3355714Skris *    "This product includes cryptographic software written by
3455714Skris *     Eric Young (eay@cryptsoft.com)"
3555714Skris *    The word 'cryptographic' can be left out if the rouines from the library
3655714Skris *    being used are not cryptographic related :-).
3755714Skris * 4. If you include any Windows specific code (or a derivative thereof) from
3855714Skris *    the apps directory (application code) you must include an acknowledgement:
3955714Skris *    "This product includes software written by Tim Hudson (tjh@cryptsoft.com)"
4055714Skris *
4155714Skris * THIS SOFTWARE IS PROVIDED BY ERIC YOUNG ``AS IS'' AND
4255714Skris * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
4355714Skris * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
4455714Skris * ARE DISCLAIMED.  IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE
4555714Skris * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
4655714Skris * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
4755714Skris * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
4855714Skris * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
4955714Skris * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
5055714Skris * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
5155714Skris * SUCH DAMAGE.
5255714Skris *
5355714Skris * The licence and distribution terms for any publically available version or
5455714Skris * derivative of this code cannot be changed.  i.e. this code cannot simply be
5555714Skris * copied and put under another distribution licence
5655714Skris * [including the GNU Public Licence.]
5755714Skris */
5855714Skris
5955714Skris/* Original version from Steven Schoch <schoch@sheba.arc.nasa.gov> */
6055714Skris
6155714Skris#include <stdio.h>
6255714Skris#include "cryptlib.h"
6355714Skris#include <openssl/bn.h>
6455714Skris#include <openssl/dsa.h>
6555714Skris#include <openssl/asn1.h>
6655714Skris
6755714Skrisconst char *DSA_version="DSA" OPENSSL_VERSION_PTEXT;
6855714Skris
6955714SkrisDSA *DSA_new(void)
7055714Skris	{
7155714Skris	DSA *ret;
7255714Skris
7355714Skris	ret=(DSA *)Malloc(sizeof(DSA));
7455714Skris	if (ret == NULL)
7555714Skris		{
7655714Skris		DSAerr(DSA_F_DSA_NEW,ERR_R_MALLOC_FAILURE);
7755714Skris		return(NULL);
7855714Skris		}
7955714Skris	ret->pad=0;
8055714Skris	ret->version=0;
8155714Skris	ret->write_params=1;
8255714Skris	ret->p=NULL;
8355714Skris	ret->q=NULL;
8455714Skris	ret->g=NULL;
8555714Skris	ret->flags=DSA_FLAG_CACHE_MONT_P;
8655714Skris
8755714Skris	ret->pub_key=NULL;
8855714Skris	ret->priv_key=NULL;
8955714Skris
9055714Skris	ret->kinv=NULL;
9155714Skris	ret->r=NULL;
9255714Skris	ret->method_mont_p=NULL;
9355714Skris
9455714Skris	ret->references=1;
9555714Skris	return(ret);
9655714Skris	}
9755714Skris
9855714Skrisvoid DSA_free(DSA *r)
9955714Skris	{
10055714Skris	int i;
10155714Skris
10255714Skris	if (r == NULL) return;
10355714Skris
10455714Skris	i=CRYPTO_add(&r->references,-1,CRYPTO_LOCK_DSA);
10555714Skris#ifdef REF_PRINT
10655714Skris	REF_PRINT("DSA",r);
10755714Skris#endif
10855714Skris	if (i > 0) return;
10955714Skris#ifdef REF_CHECK
11055714Skris	if (i < 0)
11155714Skris		{
11255714Skris		fprintf(stderr,"DSA_free, bad reference count\n");
11355714Skris		abort();
11455714Skris		}
11555714Skris#endif
11655714Skris
11755714Skris	if (r->p != NULL) BN_clear_free(r->p);
11855714Skris	if (r->q != NULL) BN_clear_free(r->q);
11955714Skris	if (r->g != NULL) BN_clear_free(r->g);
12055714Skris	if (r->pub_key != NULL) BN_clear_free(r->pub_key);
12155714Skris	if (r->priv_key != NULL) BN_clear_free(r->priv_key);
12255714Skris	if (r->kinv != NULL) BN_clear_free(r->kinv);
12355714Skris	if (r->r != NULL) BN_clear_free(r->r);
12455714Skris	if (r->method_mont_p != NULL)
12555714Skris		BN_MONT_CTX_free((BN_MONT_CTX *)r->method_mont_p);
12655714Skris	Free(r);
12755714Skris	}
12855714Skris
12955714Skrisint DSA_size(DSA *r)
13055714Skris	{
13155714Skris	int ret,i;
13255714Skris	ASN1_INTEGER bs;
13355714Skris	unsigned char buf[4];
13455714Skris
13555714Skris	i=BN_num_bits(r->q);
13655714Skris	bs.length=(i+7)/8;
13755714Skris	bs.data=buf;
13855714Skris	bs.type=V_ASN1_INTEGER;
13955714Skris	/* If the top bit is set the asn1 encoding is 1 larger. */
14055714Skris	buf[0]=0xff;
14155714Skris
14255714Skris	i=i2d_ASN1_INTEGER(&bs,NULL);
14355714Skris	i+=i; /* r and s */
14455714Skris	ret=ASN1_object_size(1,i,V_ASN1_SEQUENCE);
14555714Skris	return(ret);
14655714Skris	}
14755714Skris
14855714Skris#ifndef NO_DH
14955714SkrisDH *DSA_dup_DH(DSA *r)
15055714Skris	{
15155714Skris	/* DSA has p, q, g, optional pub_key, optional priv_key.
15255714Skris	 * DH has p, optional length, g, optional pub_key, optional priv_key.
15355714Skris	 */
15455714Skris
15555714Skris	DH *ret = NULL;
15655714Skris
15755714Skris	if (r == NULL)
15855714Skris		goto err;
15955714Skris	ret = DH_new();
16055714Skris	if (ret == NULL)
16155714Skris		goto err;
16255714Skris	if (r->p != NULL)
16355714Skris		if ((ret->p = BN_dup(r->p)) == NULL)
16455714Skris			goto err;
16555714Skris	if (r->q != NULL)
16655714Skris		ret->length = BN_num_bits(r->q);
16755714Skris	if (r->g != NULL)
16855714Skris		if ((ret->g = BN_dup(r->g)) == NULL)
16955714Skris			goto err;
17055714Skris	if (r->pub_key != NULL)
17155714Skris		if ((ret->pub_key = BN_dup(r->pub_key)) == NULL)
17255714Skris			goto err;
17355714Skris	if (r->priv_key != NULL)
17455714Skris		if ((ret->priv_key = BN_dup(r->priv_key)) == NULL)
17555714Skris			goto err;
17655714Skris
17755714Skris	return ret;
17855714Skris
17955714Skris err:
18055714Skris	if (ret != NULL)
18155714Skris		DH_free(ret);
18255714Skris	return NULL;
18355714Skris	}
18455714Skris#endif
185