1 | /* |
2 | * Copyright 1999-2016 The OpenSSL Project Authors. All Rights Reserved. |
3 | * |
4 | * Licensed under the Apache License 2.0 (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 | #include "crypto/asn1_dsa.h" |
17 | |
18 | DSA_SIG *DSA_SIG_new(void) |
19 | { |
20 | DSA_SIG *sig = OPENSSL_zalloc(sizeof(*sig)); |
21 | if (sig == NULL) |
22 | DSAerr(DSA_F_DSA_SIG_NEW, ERR_R_MALLOC_FAILURE); |
23 | return sig; |
24 | } |
25 | |
26 | void DSA_SIG_free(DSA_SIG *sig) |
27 | { |
28 | if (sig == NULL) |
29 | return; |
30 | BN_clear_free(sig->r); |
31 | BN_clear_free(sig->s); |
32 | OPENSSL_free(sig); |
33 | } |
34 | |
35 | DSA_SIG *d2i_DSA_SIG(DSA_SIG **psig, const unsigned char **ppin, long len) |
36 | { |
37 | DSA_SIG *sig; |
38 | |
39 | if (len < 0) |
40 | return NULL; |
41 | if (psig != NULL && *psig != NULL) { |
42 | sig = *psig; |
43 | } else { |
44 | sig = DSA_SIG_new(); |
45 | if (sig == NULL) |
46 | return NULL; |
47 | } |
48 | if (sig->r == NULL) |
49 | sig->r = BN_new(); |
50 | if (sig->s == NULL) |
51 | sig->s = BN_new(); |
52 | if (decode_der_dsa_sig(sig->r, sig->s, ppin, (size_t)len) == 0) { |
53 | if (psig == NULL || *psig == NULL) |
54 | DSA_SIG_free(sig); |
55 | return NULL; |
56 | } |
57 | if (psig != NULL && *psig == NULL) |
58 | *psig = sig; |
59 | return sig; |
60 | } |
61 | |
62 | int i2d_DSA_SIG(const DSA_SIG *sig, unsigned char **ppout) |
63 | { |
64 | BUF_MEM *buf = NULL; |
65 | size_t encoded_len; |
66 | WPACKET pkt; |
67 | |
68 | if (ppout == NULL) { |
69 | if (!WPACKET_init_null(&pkt, 0)) |
70 | return -1; |
71 | } else if (*ppout == NULL) { |
72 | if ((buf = BUF_MEM_new()) == NULL |
73 | || !WPACKET_init_len(&pkt, buf, 0)) { |
74 | BUF_MEM_free(buf); |
75 | return -1; |
76 | } |
77 | } else { |
78 | if (!WPACKET_init_static_len(&pkt, *ppout, SIZE_MAX, 0)) |
79 | return -1; |
80 | } |
81 | |
82 | if (!encode_der_dsa_sig(&pkt, sig->r, sig->s) |
83 | || !WPACKET_get_total_written(&pkt, &encoded_len) |
84 | || !WPACKET_finish(&pkt)) { |
85 | BUF_MEM_free(buf); |
86 | WPACKET_cleanup(&pkt); |
87 | return -1; |
88 | } |
89 | |
90 | if (ppout != NULL) { |
91 | if (*ppout == NULL) { |
92 | *ppout = (unsigned char *)buf->data; |
93 | buf->data = NULL; |
94 | BUF_MEM_free(buf); |
95 | } else { |
96 | *ppout += encoded_len; |
97 | } |
98 | } |
99 | |
100 | return (int)encoded_len; |
101 | } |
102 | |
103 | void DSA_SIG_get0(const DSA_SIG *sig, const BIGNUM **pr, const BIGNUM **ps) |
104 | { |
105 | if (pr != NULL) |
106 | *pr = sig->r; |
107 | if (ps != NULL) |
108 | *ps = sig->s; |
109 | } |
110 | |
111 | int DSA_SIG_set0(DSA_SIG *sig, BIGNUM *r, BIGNUM *s) |
112 | { |
113 | if (r == NULL || s == NULL) |
114 | return 0; |
115 | BN_clear_free(sig->r); |
116 | BN_clear_free(sig->s); |
117 | sig->r = r; |
118 | sig->s = s; |
119 | return 1; |
120 | } |
121 | |
122 | /* Override the default free and new methods */ |
123 | static int dsa_cb(int operation, ASN1_VALUE **pval, const ASN1_ITEM *it, |
124 | void *exarg) |
125 | { |
126 | if (operation == ASN1_OP_NEW_PRE) { |
127 | *pval = (ASN1_VALUE *)DSA_new(); |
128 | if (*pval != NULL) |
129 | return 2; |
130 | return 0; |
131 | } else if (operation == ASN1_OP_FREE_PRE) { |
132 | DSA_free((DSA *)*pval); |
133 | *pval = NULL; |
134 | return 2; |
135 | } |
136 | return 1; |
137 | } |
138 | |
139 | ASN1_SEQUENCE_cb(DSAPrivateKey, dsa_cb) = { |
140 | ASN1_EMBED(DSA, version, INT32), |
141 | ASN1_SIMPLE(DSA, p, BIGNUM), |
142 | ASN1_SIMPLE(DSA, q, BIGNUM), |
143 | ASN1_SIMPLE(DSA, g, BIGNUM), |
144 | ASN1_SIMPLE(DSA, pub_key, BIGNUM), |
145 | ASN1_SIMPLE(DSA, priv_key, CBIGNUM) |
146 | } static_ASN1_SEQUENCE_END_cb(DSA, DSAPrivateKey) |
147 | |
148 | IMPLEMENT_ASN1_ENCODE_FUNCTIONS_fname(DSA, DSAPrivateKey, DSAPrivateKey) |
149 | |
150 | ASN1_SEQUENCE_cb(DSAparams, dsa_cb) = { |
151 | ASN1_SIMPLE(DSA, p, BIGNUM), |
152 | ASN1_SIMPLE(DSA, q, BIGNUM), |
153 | ASN1_SIMPLE(DSA, g, BIGNUM), |
154 | } static_ASN1_SEQUENCE_END_cb(DSA, DSAparams) |
155 | |
156 | IMPLEMENT_ASN1_ENCODE_FUNCTIONS_fname(DSA, DSAparams, DSAparams) |
157 | |
158 | ASN1_SEQUENCE_cb(DSAPublicKey, dsa_cb) = { |
159 | ASN1_SIMPLE(DSA, pub_key, BIGNUM), |
160 | ASN1_SIMPLE(DSA, p, BIGNUM), |
161 | ASN1_SIMPLE(DSA, q, BIGNUM), |
162 | ASN1_SIMPLE(DSA, g, BIGNUM) |
163 | } static_ASN1_SEQUENCE_END_cb(DSA, DSAPublicKey) |
164 | |
165 | IMPLEMENT_ASN1_ENCODE_FUNCTIONS_fname(DSA, DSAPublicKey, DSAPublicKey) |
166 | |
167 | DSA *DSAparams_dup(const DSA *dsa) |
168 | { |
169 | return ASN1_item_dup(ASN1_ITEM_rptr(DSAparams), dsa); |
170 | } |
171 | |
172 | int DSA_sign(int type, const unsigned char *dgst, int dlen, |
173 | unsigned char *sig, unsigned int *siglen, DSA *dsa) |
174 | { |
175 | DSA_SIG *s; |
176 | |
177 | s = DSA_do_sign(dgst, dlen, dsa); |
178 | if (s == NULL) { |
179 | *siglen = 0; |
180 | return 0; |
181 | } |
182 | *siglen = i2d_DSA_SIG(s, &sig); |
183 | DSA_SIG_free(s); |
184 | return 1; |
185 | } |
186 | |
187 | /* data has already been hashed (probably with SHA or SHA-1). */ |
188 | /*- |
189 | * returns |
190 | * 1: correct signature |
191 | * 0: incorrect signature |
192 | * -1: error |
193 | */ |
194 | int DSA_verify(int type, const unsigned char *dgst, int dgst_len, |
195 | const unsigned char *sigbuf, int siglen, DSA *dsa) |
196 | { |
197 | DSA_SIG *s; |
198 | const unsigned char *p = sigbuf; |
199 | unsigned char *der = NULL; |
200 | int derlen = -1; |
201 | int ret = -1; |
202 | |
203 | s = DSA_SIG_new(); |
204 | if (s == NULL) |
205 | return ret; |
206 | if (d2i_DSA_SIG(&s, &p, siglen) == NULL) |
207 | goto err; |
208 | /* Ensure signature uses DER and doesn't have trailing garbage */ |
209 | derlen = i2d_DSA_SIG(s, &der); |
210 | if (derlen != siglen || memcmp(sigbuf, der, derlen)) |
211 | goto err; |
212 | ret = DSA_do_verify(dgst, dgst_len, s, dsa); |
213 | err: |
214 | OPENSSL_clear_free(der, derlen); |
215 | DSA_SIG_free(s); |
216 | return ret; |
217 | } |
218 | |