xref: /openbsd/lib/libcrypto/dsa/dsa_asn1.c (revision a6445c1d)
1 /* $OpenBSD: dsa_asn1.c,v 1.13 2014/10/18 17:20:40 jsing Exp $ */
2 /* Written by Dr Stephen N Henson (steve@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@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@cryptsoft.com).  This product includes software written by Tim
55  * Hudson (tjh@cryptsoft.com).
56  *
57  */
58 
59 #include <stdio.h>
60 
61 #include <openssl/asn1.h>
62 #include <openssl/asn1t.h>
63 #include <openssl/dsa.h>
64 #include <openssl/err.h>
65 
66 /* Override the default new methods */
67 static int
68 sig_cb(int operation, ASN1_VALUE **pval, const ASN1_ITEM *it, void *exarg)
69 {
70 	if (operation == ASN1_OP_NEW_PRE) {
71 		DSA_SIG *sig;
72 
73 		sig = malloc(sizeof(DSA_SIG));
74 		if (!sig) {
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
95 dsa_cb(int operation, ASN1_VALUE **pval, const ASN1_ITEM *it, void *exarg)
96 {
97 	if (operation == ASN1_OP_NEW_PRE) {
98 		*pval = (ASN1_VALUE *)DSA_new();
99 		if (*pval)
100 			return 2;
101 		return 0;
102 	} else if (operation == ASN1_OP_FREE_PRE) {
103 		DSA_free((DSA *)*pval);
104 		*pval = NULL;
105 		return 2;
106 	}
107 	return 1;
108 }
109 
110 ASN1_SEQUENCE_cb(DSAPrivateKey, dsa_cb) = {
111 	ASN1_SIMPLE(DSA, version, LONG),
112 	ASN1_SIMPLE(DSA, p, BIGNUM),
113 	ASN1_SIMPLE(DSA, q, BIGNUM),
114 	ASN1_SIMPLE(DSA, g, BIGNUM),
115 	ASN1_SIMPLE(DSA, pub_key, BIGNUM),
116 	ASN1_SIMPLE(DSA, priv_key, BIGNUM)
117 } ASN1_SEQUENCE_END_cb(DSA, DSAPrivateKey)
118 
119 IMPLEMENT_ASN1_ENCODE_FUNCTIONS_const_fname(DSA, DSAPrivateKey, DSAPrivateKey)
120 
121 ASN1_SEQUENCE_cb(DSAparams, dsa_cb) = {
122 	ASN1_SIMPLE(DSA, p, BIGNUM),
123 	ASN1_SIMPLE(DSA, q, BIGNUM),
124 	ASN1_SIMPLE(DSA, g, BIGNUM),
125 } ASN1_SEQUENCE_END_cb(DSA, DSAparams)
126 
127 IMPLEMENT_ASN1_ENCODE_FUNCTIONS_const_fname(DSA, DSAparams, DSAparams)
128 
129 /*
130  * DSA public key is a bit trickier... its effectively a CHOICE type
131  * decided by a field called write_params which can either write out
132  * just the public key as an INTEGER or the parameters and public key
133  * in a SEQUENCE
134  */
135 
136 ASN1_SEQUENCE(dsa_pub_internal) = {
137 	ASN1_SIMPLE(DSA, pub_key, BIGNUM),
138 	ASN1_SIMPLE(DSA, p, BIGNUM),
139 	ASN1_SIMPLE(DSA, q, BIGNUM),
140 	ASN1_SIMPLE(DSA, g, BIGNUM)
141 } ASN1_SEQUENCE_END_name(DSA, dsa_pub_internal)
142 
143 ASN1_CHOICE_cb(DSAPublicKey, dsa_cb) = {
144 	ASN1_SIMPLE(DSA, pub_key, BIGNUM),
145 	ASN1_EX_COMBINE(0, 0, dsa_pub_internal)
146 } ASN1_CHOICE_END_cb(DSA, DSAPublicKey, write_params)
147 
148 IMPLEMENT_ASN1_ENCODE_FUNCTIONS_const_fname(DSA, DSAPublicKey, DSAPublicKey)
149 
150 DSA *
151 DSAparams_dup(DSA *dsa)
152 {
153 	return ASN1_item_dup(ASN1_ITEM_rptr(DSAparams), dsa);
154 }
155 
156 int
157 DSA_sign(int type, const unsigned char *dgst, int dlen, unsigned char *sig,
158     unsigned int *siglen, DSA *dsa)
159 {
160 	DSA_SIG *s;
161 
162 	s = DSA_do_sign(dgst, dlen, dsa);
163 	if (s == NULL) {
164 		*siglen = 0;
165 		return 0;
166 	}
167 	*siglen = i2d_DSA_SIG(s,&sig);
168 	DSA_SIG_free(s);
169 	return 1;
170 }
171 
172 /*
173  * data has already been hashed (probably with SHA or SHA-1).
174  * returns
175  *      1: correct signature
176  *      0: incorrect signature
177  *     -1: error
178  */
179 int
180 DSA_verify(int type, const unsigned char *dgst, int dgst_len,
181     const unsigned char *sigbuf, int siglen, DSA *dsa)
182 {
183 	DSA_SIG *s;
184 	int ret = -1;
185 
186 	s = DSA_SIG_new();
187 	if (s == NULL)
188 		return ret;
189 	if (d2i_DSA_SIG(&s, &sigbuf, siglen) == NULL)
190 		goto err;
191 	ret = DSA_do_verify(dgst, dgst_len, s, dsa);
192 err:
193 	DSA_SIG_free(s);
194 	return ret;
195 }
196