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      1 /* dsa_asn1.c */
      2 /* Written by Dr Stephen N Henson (steve (at) openssl.org) for the OpenSSL
      3  * project 2000.
      4  */
      5 /* ====================================================================
      6  * Copyright (c) 2000-2005 The OpenSSL Project.  All rights reserved.
      7  *
      8  * Redistribution and use in source and binary forms, with or without
      9  * modification, are permitted provided that the following conditions
     10  * are met:
     11  *
     12  * 1. Redistributions of source code must retain the above copyright
     13  *    notice, this list of conditions and the following disclaimer.
     14  *
     15  * 2. Redistributions in binary form must reproduce the above copyright
     16  *    notice, this list of conditions and the following disclaimer in
     17  *    the documentation and/or other materials provided with the
     18  *    distribution.
     19  *
     20  * 3. All advertising materials mentioning features or use of this
     21  *    software must display the following acknowledgment:
     22  *    "This product includes software developed by the OpenSSL Project
     23  *    for use in the OpenSSL Toolkit. (http://www.OpenSSL.org/)"
     24  *
     25  * 4. The names "OpenSSL Toolkit" and "OpenSSL Project" must not be used to
     26  *    endorse or promote products derived from this software without
     27  *    prior written permission. For written permission, please contact
     28  *    licensing (at) OpenSSL.org.
     29  *
     30  * 5. Products derived from this software may not be called "OpenSSL"
     31  *    nor may "OpenSSL" appear in their names without prior written
     32  *    permission of the OpenSSL Project.
     33  *
     34  * 6. Redistributions of any form whatsoever must retain the following
     35  *    acknowledgment:
     36  *    "This product includes software developed by the OpenSSL Project
     37  *    for use in the OpenSSL Toolkit (http://www.OpenSSL.org/)"
     38  *
     39  * THIS SOFTWARE IS PROVIDED BY THE OpenSSL PROJECT ``AS IS'' AND ANY
     40  * EXPRESSED OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
     41  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR
     42  * PURPOSE ARE DISCLAIMED.  IN NO EVENT SHALL THE OpenSSL PROJECT OR
     43  * ITS CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
     44  * SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT
     45  * NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES;
     46  * LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
     47  * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT,
     48  * STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE)
     49  * ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED
     50  * OF THE POSSIBILITY OF SUCH DAMAGE.
     51  * ====================================================================
     52  *
     53  * This product includes cryptographic software written by Eric Young
     54  * (eay (at) cryptsoft.com).  This product includes software written by Tim
     55  * Hudson (tjh (at) cryptsoft.com).
     56  *
     57  */
     58 
     59 #include <stdio.h>
     60 #include "cryptlib.h"
     61 #include <openssl/dsa.h>
     62 #include <openssl/asn1.h>
     63 #include <openssl/asn1t.h>
     64 #include <openssl/rand.h>
     65 
     66 /* Override the default new methods */
     67 static int sig_cb(int operation, ASN1_VALUE **pval, const ASN1_ITEM *it,
     68 								void *exarg)
     69 {
     70 	if(operation == ASN1_OP_NEW_PRE) {
     71 		DSA_SIG *sig;
     72 		sig = OPENSSL_malloc(sizeof(DSA_SIG));
     73 		if (!sig)
     74 			{
     75 			DSAerr(DSA_F_SIG_CB, ERR_R_MALLOC_FAILURE);
     76 			return 0;
     77 			}
     78 		sig->r = NULL;
     79 		sig->s = NULL;
     80 		*pval = (ASN1_VALUE *)sig;
     81 		return 2;
     82 	}
     83 	return 1;
     84 }
     85 
     86 ASN1_SEQUENCE_cb(DSA_SIG, sig_cb) = {
     87 	ASN1_SIMPLE(DSA_SIG, r, CBIGNUM),
     88 	ASN1_SIMPLE(DSA_SIG, s, CBIGNUM)
     89 } ASN1_SEQUENCE_END_cb(DSA_SIG, DSA_SIG)
     90 
     91 IMPLEMENT_ASN1_ENCODE_FUNCTIONS_const_fname(DSA_SIG, DSA_SIG, DSA_SIG)
     92 
     93 /* Override the default free and new methods */
     94 static int dsa_cb(int operation, ASN1_VALUE **pval, const ASN1_ITEM *it,
     95 							void *exarg)
     96 {
     97 	if(operation == ASN1_OP_NEW_PRE) {
     98 		*pval = (ASN1_VALUE *)DSA_new();
     99 		if(*pval) return 2;
    100 		return 0;
    101 	} else if(operation == ASN1_OP_FREE_PRE) {
    102 		DSA_free((DSA *)*pval);
    103 		*pval = NULL;
    104 		return 2;
    105 	}
    106 	return 1;
    107 }
    108 
    109 ASN1_SEQUENCE_cb(DSAPrivateKey, dsa_cb) = {
    110 	ASN1_SIMPLE(DSA, version, LONG),
    111 	ASN1_SIMPLE(DSA, p, BIGNUM),
    112 	ASN1_SIMPLE(DSA, q, BIGNUM),
    113 	ASN1_SIMPLE(DSA, g, BIGNUM),
    114 	ASN1_SIMPLE(DSA, pub_key, BIGNUM),
    115 	ASN1_SIMPLE(DSA, priv_key, BIGNUM)
    116 } ASN1_SEQUENCE_END_cb(DSA, DSAPrivateKey)
    117 
    118 IMPLEMENT_ASN1_ENCODE_FUNCTIONS_const_fname(DSA, DSAPrivateKey, DSAPrivateKey)
    119 
    120 ASN1_SEQUENCE_cb(DSAparams, dsa_cb) = {
    121 	ASN1_SIMPLE(DSA, p, BIGNUM),
    122 	ASN1_SIMPLE(DSA, q, BIGNUM),
    123 	ASN1_SIMPLE(DSA, g, BIGNUM),
    124 } ASN1_SEQUENCE_END_cb(DSA, DSAparams)
    125 
    126 IMPLEMENT_ASN1_ENCODE_FUNCTIONS_const_fname(DSA, DSAparams, DSAparams)
    127 
    128 /* DSA public key is a bit trickier... its effectively a CHOICE type
    129  * decided by a field called write_params which can either write out
    130  * just the public key as an INTEGER or the parameters and public key
    131  * in a SEQUENCE
    132  */
    133 
    134 ASN1_SEQUENCE(dsa_pub_internal) = {
    135 	ASN1_SIMPLE(DSA, pub_key, BIGNUM),
    136 	ASN1_SIMPLE(DSA, p, BIGNUM),
    137 	ASN1_SIMPLE(DSA, q, BIGNUM),
    138 	ASN1_SIMPLE(DSA, g, BIGNUM)
    139 } ASN1_SEQUENCE_END_name(DSA, dsa_pub_internal)
    140 
    141 ASN1_CHOICE_cb(DSAPublicKey, dsa_cb) = {
    142 	ASN1_SIMPLE(DSA, pub_key, BIGNUM),
    143 	ASN1_EX_COMBINE(0, 0, dsa_pub_internal)
    144 } ASN1_CHOICE_END_cb(DSA, DSAPublicKey, write_params)
    145 
    146 IMPLEMENT_ASN1_ENCODE_FUNCTIONS_const_fname(DSA, DSAPublicKey, DSAPublicKey)
    147 
    148 DSA *DSAparams_dup(DSA *dsa)
    149 	{
    150 	return ASN1_item_dup(ASN1_ITEM_rptr(DSAparams), dsa);
    151 	}
    152 
    153 int DSA_sign(int type, const unsigned char *dgst, int dlen, unsigned char *sig,
    154 	     unsigned int *siglen, DSA *dsa)
    155 	{
    156 	DSA_SIG *s;
    157 	RAND_seed(dgst, dlen);
    158 	s=DSA_do_sign(dgst,dlen,dsa);
    159 	if (s == NULL)
    160 		{
    161 		*siglen=0;
    162 		return(0);
    163 		}
    164 	*siglen=i2d_DSA_SIG(s,&sig);
    165 	DSA_SIG_free(s);
    166 	return(1);
    167 	}
    168 
    169 /* data has already been hashed (probably with SHA or SHA-1). */
    170 /* returns
    171  *      1: correct signature
    172  *      0: incorrect signature
    173  *     -1: error
    174  */
    175 int DSA_verify(int type, const unsigned char *dgst, int dgst_len,
    176 	     const unsigned char *sigbuf, int siglen, DSA *dsa)
    177 	{
    178 	DSA_SIG *s;
    179 	int ret=-1;
    180 
    181 	s = DSA_SIG_new();
    182 	if (s == NULL) return(ret);
    183 	if (d2i_DSA_SIG(&s,&sigbuf,siglen) == NULL) goto err;
    184 	ret=DSA_do_verify(dgst,dgst_len,s,dsa);
    185 err:
    186 	DSA_SIG_free(s);
    187 	return(ret);
    188 	}
    189