Line data Source code
1 : /* dsa_asn1.c */
2 : /*
3 : * Written by Dr Stephen N Henson (steve@openssl.org) for the OpenSSL project
4 : * 2000.
5 : */
6 : /* ====================================================================
7 : * Copyright (c) 2000-2005 The OpenSSL Project. All rights reserved.
8 : *
9 : * Redistribution and use in source and binary forms, with or without
10 : * modification, are permitted provided that the following conditions
11 : * are met:
12 : *
13 : * 1. Redistributions of source code must retain the above copyright
14 : * notice, this list of conditions and the following disclaimer.
15 : *
16 : * 2. Redistributions in binary form must reproduce the above copyright
17 : * notice, this list of conditions and the following disclaimer in
18 : * the documentation and/or other materials provided with the
19 : * distribution.
20 : *
21 : * 3. All advertising materials mentioning features or use of this
22 : * software must display the following acknowledgment:
23 : * "This product includes software developed by the OpenSSL Project
24 : * for use in the OpenSSL Toolkit. (http://www.OpenSSL.org/)"
25 : *
26 : * 4. The names "OpenSSL Toolkit" and "OpenSSL Project" must not be used to
27 : * endorse or promote products derived from this software without
28 : * prior written permission. For written permission, please contact
29 : * licensing@OpenSSL.org.
30 : *
31 : * 5. Products derived from this software may not be called "OpenSSL"
32 : * nor may "OpenSSL" appear in their names without prior written
33 : * permission of the OpenSSL Project.
34 : *
35 : * 6. Redistributions of any form whatsoever must retain the following
36 : * acknowledgment:
37 : * "This product includes software developed by the OpenSSL Project
38 : * for use in the OpenSSL Toolkit (http://www.OpenSSL.org/)"
39 : *
40 : * THIS SOFTWARE IS PROVIDED BY THE OpenSSL PROJECT ``AS IS'' AND ANY
41 : * EXPRESSED OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
42 : * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR
43 : * PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE OpenSSL PROJECT OR
44 : * ITS CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
45 : * SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT
46 : * NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES;
47 : * LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
48 : * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT,
49 : * STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE)
50 : * ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED
51 : * OF THE POSSIBILITY OF SUCH DAMAGE.
52 : * ====================================================================
53 : *
54 : * This product includes cryptographic software written by Eric Young
55 : * (eay@cryptsoft.com). This product includes software written by Tim
56 : * Hudson (tjh@cryptsoft.com).
57 : *
58 : */
59 :
60 : #include <stdio.h>
61 : #include "cryptlib.h"
62 : #include <openssl/dsa.h>
63 : #include <openssl/asn1.h>
64 : #include <openssl/asn1t.h>
65 : #include <openssl/rand.h>
66 :
67 : /* Override the default new methods */
68 0 : static int sig_cb(int operation, ASN1_VALUE **pval, const ASN1_ITEM *it,
69 : void *exarg)
70 : {
71 0 : if (operation == ASN1_OP_NEW_PRE) {
72 : DSA_SIG *sig;
73 0 : sig = OPENSSL_malloc(sizeof(DSA_SIG));
74 0 : if (!sig) {
75 0 : DSAerr(DSA_F_SIG_CB, ERR_R_MALLOC_FAILURE);
76 0 : return 0;
77 : }
78 0 : sig->r = NULL;
79 0 : sig->s = NULL;
80 0 : *pval = (ASN1_VALUE *)sig;
81 0 : 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 0 : IMPLEMENT_ASN1_ENCODE_FUNCTIONS_const_fname(DSA_SIG, DSA_SIG, DSA_SIG)
92 :
93 : /* Override the default free and new methods */
94 0 : static int dsa_cb(int operation, ASN1_VALUE **pval, const ASN1_ITEM *it,
95 : void *exarg)
96 : {
97 0 : if (operation == ASN1_OP_NEW_PRE) {
98 0 : *pval = (ASN1_VALUE *)DSA_new();
99 0 : if (*pval)
100 : return 2;
101 0 : return 0;
102 0 : } else if (operation == ASN1_OP_FREE_PRE) {
103 0 : DSA_free((DSA *)*pval);
104 0 : *pval = NULL;
105 0 : 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 0 : 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 0 : IMPLEMENT_ASN1_ENCODE_FUNCTIONS_const_fname(DSA, DSAparams, DSAparams)
128 :
129 : /*
130 : * DSA public key is a bit trickier... its effectively a CHOICE type decided
131 : * by a field called write_params which can either write out just the public
132 : * key as an INTEGER or the parameters and public key in a SEQUENCE
133 : */
134 :
135 : ASN1_SEQUENCE(dsa_pub_internal) = {
136 : ASN1_SIMPLE(DSA, pub_key, BIGNUM),
137 : ASN1_SIMPLE(DSA, p, BIGNUM),
138 : ASN1_SIMPLE(DSA, q, BIGNUM),
139 : ASN1_SIMPLE(DSA, g, BIGNUM)
140 : } ASN1_SEQUENCE_END_name(DSA, dsa_pub_internal)
141 :
142 : ASN1_CHOICE_cb(DSAPublicKey, dsa_cb) = {
143 : ASN1_SIMPLE(DSA, pub_key, BIGNUM),
144 : ASN1_EX_COMBINE(0, 0, dsa_pub_internal)
145 : } ASN1_CHOICE_END_cb(DSA, DSAPublicKey, write_params)
146 :
147 0 : IMPLEMENT_ASN1_ENCODE_FUNCTIONS_const_fname(DSA, DSAPublicKey, DSAPublicKey)
148 :
149 0 : DSA *DSAparams_dup(DSA *dsa)
150 : {
151 0 : return ASN1_item_dup(ASN1_ITEM_rptr(DSAparams), dsa);
152 : }
153 :
154 0 : int DSA_sign(int type, const unsigned char *dgst, int dlen,
155 : unsigned char *sig, unsigned int *siglen, DSA *dsa)
156 : {
157 : DSA_SIG *s;
158 0 : RAND_seed(dgst, dlen);
159 0 : s = DSA_do_sign(dgst, dlen, dsa);
160 0 : if (s == NULL) {
161 0 : *siglen = 0;
162 0 : return (0);
163 : }
164 0 : *siglen = i2d_DSA_SIG(s, &sig);
165 0 : DSA_SIG_free(s);
166 0 : return (1);
167 : }
168 :
169 : /* data has already been hashed (probably with SHA or SHA-1). */
170 : /*-
171 : * returns
172 : * 1: correct signature
173 : * 0: incorrect signature
174 : * -1: error
175 : */
176 0 : int DSA_verify(int type, const unsigned char *dgst, int dgst_len,
177 : const unsigned char *sigbuf, int siglen, DSA *dsa)
178 : {
179 : DSA_SIG *s;
180 0 : const unsigned char *p = sigbuf;
181 0 : unsigned char *der = NULL;
182 : int derlen = -1;
183 : int ret = -1;
184 :
185 0 : s = DSA_SIG_new();
186 0 : if (s == NULL)
187 : return (ret);
188 0 : if (d2i_DSA_SIG(&s, &p, siglen) == NULL)
189 : goto err;
190 : /* Ensure signature uses DER and doesn't have trailing garbage */
191 0 : derlen = i2d_DSA_SIG(s, &der);
192 0 : if (derlen != siglen || memcmp(sigbuf, der, derlen))
193 : goto err;
194 0 : ret = DSA_do_verify(dgst, dgst_len, s, dsa);
195 : err:
196 0 : if (derlen > 0) {
197 0 : OPENSSL_cleanse(der, derlen);
198 0 : OPENSSL_free(der);
199 : }
200 0 : DSA_SIG_free(s);
201 0 : return (ret);
202 : }
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