1 /*
2 * Copyright 1999-2016 The OpenSSL Project Authors. All Rights Reserved.
3 *
4 * Licensed under the OpenSSL license (the "License"). You may not use
5 * this file except in compliance with the License. You can obtain a copy
6 * in the file LICENSE in the source distribution or at
7 * https://www.openssl.org/source/license.html
8 */
9
10 #include <stdio.h>
11 #include "internal/cryptlib.h"
12 #include "dsa_local.h"
13 #include <openssl/asn1.h>
14 #include <openssl/asn1t.h>
15 #include <openssl/rand.h>
16
17 ASN1_SEQUENCE(DSA_SIG) = {
18 ASN1_SIMPLE(DSA_SIG, r, CBIGNUM),
19 ASN1_SIMPLE(DSA_SIG, s, CBIGNUM)
20 } static_ASN1_SEQUENCE_END(DSA_SIG)
21
22 IMPLEMENT_ASN1_ENCODE_FUNCTIONS_const_fname(DSA_SIG, DSA_SIG, DSA_SIG)
23
24 DSA_SIG *DSA_SIG_new(void)
25 {
26 DSA_SIG *sig = OPENSSL_zalloc(sizeof(*sig));
27 if (sig == NULL)
28 DSAerr(DSA_F_DSA_SIG_NEW, ERR_R_MALLOC_FAILURE);
29 return sig;
30 }
31
DSA_SIG_free(DSA_SIG * sig)32 void DSA_SIG_free(DSA_SIG *sig)
33 {
34 if (sig == NULL)
35 return;
36 BN_clear_free(sig->r);
37 BN_clear_free(sig->s);
38 OPENSSL_free(sig);
39 }
40
DSA_SIG_get0(const DSA_SIG * sig,const BIGNUM ** pr,const BIGNUM ** ps)41 void DSA_SIG_get0(const DSA_SIG *sig, const BIGNUM **pr, const BIGNUM **ps)
42 {
43 if (pr != NULL)
44 *pr = sig->r;
45 if (ps != NULL)
46 *ps = sig->s;
47 }
48
DSA_SIG_set0(DSA_SIG * sig,BIGNUM * r,BIGNUM * s)49 int DSA_SIG_set0(DSA_SIG *sig, BIGNUM *r, BIGNUM *s)
50 {
51 if (r == NULL || s == NULL)
52 return 0;
53 BN_clear_free(sig->r);
54 BN_clear_free(sig->s);
55 sig->r = r;
56 sig->s = s;
57 return 1;
58 }
59
60 /* Override the default free and new methods */
dsa_cb(int operation,ASN1_VALUE ** pval,const ASN1_ITEM * it,void * exarg)61 static int dsa_cb(int operation, ASN1_VALUE **pval, const ASN1_ITEM *it,
62 void *exarg)
63 {
64 if (operation == ASN1_OP_NEW_PRE) {
65 *pval = (ASN1_VALUE *)DSA_new();
66 if (*pval != NULL)
67 return 2;
68 return 0;
69 } else if (operation == ASN1_OP_FREE_PRE) {
70 DSA_free((DSA *)*pval);
71 *pval = NULL;
72 return 2;
73 }
74 return 1;
75 }
76
77 ASN1_SEQUENCE_cb(DSAPrivateKey, dsa_cb) = {
78 ASN1_EMBED(DSA, version, INT32),
79 ASN1_SIMPLE(DSA, p, BIGNUM),
80 ASN1_SIMPLE(DSA, q, BIGNUM),
81 ASN1_SIMPLE(DSA, g, BIGNUM),
82 ASN1_SIMPLE(DSA, pub_key, BIGNUM),
83 ASN1_SIMPLE(DSA, priv_key, CBIGNUM)
84 } static_ASN1_SEQUENCE_END_cb(DSA, DSAPrivateKey)
85
86 IMPLEMENT_ASN1_ENCODE_FUNCTIONS_const_fname(DSA, DSAPrivateKey, DSAPrivateKey)
87
88 ASN1_SEQUENCE_cb(DSAparams, dsa_cb) = {
89 ASN1_SIMPLE(DSA, p, BIGNUM),
90 ASN1_SIMPLE(DSA, q, BIGNUM),
91 ASN1_SIMPLE(DSA, g, BIGNUM),
92 } static_ASN1_SEQUENCE_END_cb(DSA, DSAparams)
93
94 IMPLEMENT_ASN1_ENCODE_FUNCTIONS_const_fname(DSA, DSAparams, DSAparams)
95
96 ASN1_SEQUENCE_cb(DSAPublicKey, dsa_cb) = {
97 ASN1_SIMPLE(DSA, pub_key, BIGNUM),
98 ASN1_SIMPLE(DSA, p, BIGNUM),
99 ASN1_SIMPLE(DSA, q, BIGNUM),
100 ASN1_SIMPLE(DSA, g, BIGNUM)
101 } static_ASN1_SEQUENCE_END_cb(DSA, DSAPublicKey)
102
103 IMPLEMENT_ASN1_ENCODE_FUNCTIONS_const_fname(DSA, DSAPublicKey, DSAPublicKey)
104
105 DSA *DSAparams_dup(DSA *dsa)
106 {
107 return ASN1_item_dup(ASN1_ITEM_rptr(DSAparams), dsa);
108 }
109
DSA_sign(int type,const unsigned char * dgst,int dlen,unsigned char * sig,unsigned int * siglen,DSA * dsa)110 int DSA_sign(int type, const unsigned char *dgst, int dlen,
111 unsigned char *sig, unsigned int *siglen, DSA *dsa)
112 {
113 DSA_SIG *s;
114
115 s = DSA_do_sign(dgst, dlen, dsa);
116 if (s == NULL) {
117 *siglen = 0;
118 return 0;
119 }
120 *siglen = i2d_DSA_SIG(s, &sig);
121 DSA_SIG_free(s);
122 return 1;
123 }
124
125 /* data has already been hashed (probably with SHA or SHA-1). */
126 /*-
127 * returns
128 * 1: correct signature
129 * 0: incorrect signature
130 * -1: error
131 */
DSA_verify(int type,const unsigned char * dgst,int dgst_len,const unsigned char * sigbuf,int siglen,DSA * dsa)132 int DSA_verify(int type, const unsigned char *dgst, int dgst_len,
133 const unsigned char *sigbuf, int siglen, DSA *dsa)
134 {
135 DSA_SIG *s;
136 const unsigned char *p = sigbuf;
137 unsigned char *der = NULL;
138 int derlen = -1;
139 int ret = -1;
140
141 s = DSA_SIG_new();
142 if (s == NULL)
143 return ret;
144 if (d2i_DSA_SIG(&s, &p, siglen) == NULL)
145 goto err;
146 /* Ensure signature uses DER and doesn't have trailing garbage */
147 derlen = i2d_DSA_SIG(s, &der);
148 if (derlen != siglen || memcmp(sigbuf, der, derlen))
149 goto err;
150 ret = DSA_do_verify(dgst, dgst_len, s, dsa);
151 err:
152 OPENSSL_clear_free(der, derlen);
153 DSA_SIG_free(s);
154 return ret;
155 }
156