1/*
2 * Copyright 2006-2018 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 <openssl/asn1t.h>
13#include <openssl/x509.h>
14#include <openssl/evp.h>
15#include <openssl/bn.h>
16#include "crypto/evp.h"
17#include "dsa_local.h"
18
19/* DSA pkey context structure */
20
21typedef struct {
22 /* Parameter gen parameters */
23 int nbits; /* size of p in bits (default: 2048) */
24 int qbits; /* size of q in bits (default: 224) */
25 const EVP_MD *pmd; /* MD for parameter generation */
26 /* Keygen callback info */
27 int gentmp[2];
28 /* message digest */
29 const EVP_MD *md; /* MD for the signature */
30} DSA_PKEY_CTX;
31
32static int pkey_dsa_init(EVP_PKEY_CTX *ctx)
33{
34 DSA_PKEY_CTX *dctx = OPENSSL_malloc(sizeof(*dctx));
35
36 if (dctx == NULL)
37 return 0;
38 dctx->nbits = 2048;
39 dctx->qbits = 224;
40 dctx->pmd = NULL;
41 dctx->md = NULL;
42
43 ctx->data = dctx;
44 ctx->keygen_info = dctx->gentmp;
45 ctx->keygen_info_count = 2;
46
47 return 1;
48}
49
50static int pkey_dsa_copy(EVP_PKEY_CTX *dst, const EVP_PKEY_CTX *src)
51{
52 DSA_PKEY_CTX *dctx, *sctx;
53
54 if (!pkey_dsa_init(dst))
55 return 0;
56 sctx = src->data;
57 dctx = dst->data;
58 dctx->nbits = sctx->nbits;
59 dctx->qbits = sctx->qbits;
60 dctx->pmd = sctx->pmd;
61 dctx->md = sctx->md;
62 return 1;
63}
64
65static void pkey_dsa_cleanup(EVP_PKEY_CTX *ctx)
66{
67 DSA_PKEY_CTX *dctx = ctx->data;
68 OPENSSL_free(dctx);
69}
70
71static int pkey_dsa_sign(EVP_PKEY_CTX *ctx, unsigned char *sig,
72 size_t *siglen, const unsigned char *tbs,
73 size_t tbslen)
74{
75 int ret;
76 unsigned int sltmp;
77 DSA_PKEY_CTX *dctx = ctx->data;
78 DSA *dsa = ctx->pkey->pkey.dsa;
79
80 if (dctx->md != NULL && tbslen != (size_t)EVP_MD_size(dctx->md))
81 return 0;
82
83 ret = DSA_sign(0, tbs, tbslen, sig, &sltmp, dsa);
84
85 if (ret <= 0)
86 return ret;
87 *siglen = sltmp;
88 return 1;
89}
90
91static int pkey_dsa_verify(EVP_PKEY_CTX *ctx,
92 const unsigned char *sig, size_t siglen,
93 const unsigned char *tbs, size_t tbslen)
94{
95 int ret;
96 DSA_PKEY_CTX *dctx = ctx->data;
97 DSA *dsa = ctx->pkey->pkey.dsa;
98
99 if (dctx->md != NULL && tbslen != (size_t)EVP_MD_size(dctx->md))
100 return 0;
101
102 ret = DSA_verify(0, tbs, tbslen, sig, siglen, dsa);
103
104 return ret;
105}
106
107static int pkey_dsa_ctrl(EVP_PKEY_CTX *ctx, int type, int p1, void *p2)
108{
109 DSA_PKEY_CTX *dctx = ctx->data;
110
111 switch (type) {
112 case EVP_PKEY_CTRL_DSA_PARAMGEN_BITS:
113 if (p1 < 256)
114 return -2;
115 dctx->nbits = p1;
116 return 1;
117
118 case EVP_PKEY_CTRL_DSA_PARAMGEN_Q_BITS:
119 if (p1 != 160 && p1 != 224 && p1 && p1 != 256)
120 return -2;
121 dctx->qbits = p1;
122 return 1;
123
124 case EVP_PKEY_CTRL_DSA_PARAMGEN_MD:
125 if (EVP_MD_type((const EVP_MD *)p2) != NID_sha1 &&
126 EVP_MD_type((const EVP_MD *)p2) != NID_sha224 &&
127 EVP_MD_type((const EVP_MD *)p2) != NID_sha256) {
128 DSAerr(DSA_F_PKEY_DSA_CTRL, DSA_R_INVALID_DIGEST_TYPE);
129 return 0;
130 }
131 dctx->pmd = p2;
132 return 1;
133
134 case EVP_PKEY_CTRL_MD:
135 if (EVP_MD_type((const EVP_MD *)p2) != NID_sha1 &&
136 EVP_MD_type((const EVP_MD *)p2) != NID_dsa &&
137 EVP_MD_type((const EVP_MD *)p2) != NID_dsaWithSHA &&
138 EVP_MD_type((const EVP_MD *)p2) != NID_sha224 &&
139 EVP_MD_type((const EVP_MD *)p2) != NID_sha256 &&
140 EVP_MD_type((const EVP_MD *)p2) != NID_sha384 &&
141 EVP_MD_type((const EVP_MD *)p2) != NID_sha512 &&
142 EVP_MD_type((const EVP_MD *)p2) != NID_sha3_224 &&
143 EVP_MD_type((const EVP_MD *)p2) != NID_sha3_256 &&
144 EVP_MD_type((const EVP_MD *)p2) != NID_sha3_384 &&
145 EVP_MD_type((const EVP_MD *)p2) != NID_sha3_512) {
146 DSAerr(DSA_F_PKEY_DSA_CTRL, DSA_R_INVALID_DIGEST_TYPE);
147 return 0;
148 }
149 dctx->md = p2;
150 return 1;
151
152 case EVP_PKEY_CTRL_GET_MD:
153 *(const EVP_MD **)p2 = dctx->md;
154 return 1;
155
156 case EVP_PKEY_CTRL_DIGESTINIT:
157 case EVP_PKEY_CTRL_PKCS7_SIGN:
158 case EVP_PKEY_CTRL_CMS_SIGN:
159 return 1;
160
161 case EVP_PKEY_CTRL_PEER_KEY:
162 DSAerr(DSA_F_PKEY_DSA_CTRL,
163 EVP_R_OPERATION_NOT_SUPPORTED_FOR_THIS_KEYTYPE);
164 return -2;
165 default:
166 return -2;
167
168 }
169}
170
171static int pkey_dsa_ctrl_str(EVP_PKEY_CTX *ctx,
172 const char *type, const char *value)
173{
174 if (strcmp(type, "dsa_paramgen_bits") == 0) {
175 int nbits;
176 nbits = atoi(value);
177 return EVP_PKEY_CTX_set_dsa_paramgen_bits(ctx, nbits);
178 }
179 if (strcmp(type, "dsa_paramgen_q_bits") == 0) {
180 int qbits = atoi(value);
181 return EVP_PKEY_CTX_set_dsa_paramgen_q_bits(ctx, qbits);
182 }
183 if (strcmp(type, "dsa_paramgen_md") == 0) {
184 const EVP_MD *md = EVP_get_digestbyname(value);
185
186 if (md == NULL) {
187 DSAerr(DSA_F_PKEY_DSA_CTRL_STR, DSA_R_INVALID_DIGEST_TYPE);
188 return 0;
189 }
190 return EVP_PKEY_CTX_set_dsa_paramgen_md(ctx, md);
191 }
192 return -2;
193}
194
195static int pkey_dsa_paramgen(EVP_PKEY_CTX *ctx, EVP_PKEY *pkey)
196{
197 DSA *dsa = NULL;
198 DSA_PKEY_CTX *dctx = ctx->data;
199 BN_GENCB *pcb;
200 int ret;
201
202 if (ctx->pkey_gencb) {
203 pcb = BN_GENCB_new();
204 if (pcb == NULL)
205 return 0;
206 evp_pkey_set_cb_translate(pcb, ctx);
207 } else
208 pcb = NULL;
209 dsa = DSA_new();
210 if (dsa == NULL) {
211 BN_GENCB_free(pcb);
212 return 0;
213 }
214 ret = dsa_builtin_paramgen(dsa, dctx->nbits, dctx->qbits, dctx->pmd,
215 NULL, 0, NULL, NULL, NULL, pcb);
216 BN_GENCB_free(pcb);
217 if (ret)
218 EVP_PKEY_assign_DSA(pkey, dsa);
219 else
220 DSA_free(dsa);
221 return ret;
222}
223
224static int pkey_dsa_keygen(EVP_PKEY_CTX *ctx, EVP_PKEY *pkey)
225{
226 DSA *dsa = NULL;
227
228 if (ctx->pkey == NULL) {
229 DSAerr(DSA_F_PKEY_DSA_KEYGEN, DSA_R_NO_PARAMETERS_SET);
230 return 0;
231 }
232 dsa = DSA_new();
233 if (dsa == NULL)
234 return 0;
235 EVP_PKEY_assign_DSA(pkey, dsa);
236 /* Note: if error return, pkey is freed by parent routine */
237 if (!EVP_PKEY_copy_parameters(pkey, ctx->pkey))
238 return 0;
239 return DSA_generate_key(pkey->pkey.dsa);
240}
241
242static const EVP_PKEY_METHOD dsa_pkey_meth = {
243 EVP_PKEY_DSA,
244 EVP_PKEY_FLAG_AUTOARGLEN,
245 pkey_dsa_init,
246 pkey_dsa_copy,
247 pkey_dsa_cleanup,
248
249 0,
250 pkey_dsa_paramgen,
251
252 0,
253 pkey_dsa_keygen,
254
255 0,
256 pkey_dsa_sign,
257
258 0,
259 pkey_dsa_verify,
260
261 0, 0,
262
263 0, 0, 0, 0,
264
265 0, 0,
266
267 0, 0,
268
269 0, 0,
270
271 pkey_dsa_ctrl,
272 pkey_dsa_ctrl_str
273};
274
275const EVP_PKEY_METHOD *dsa_pkey_method(void)
276{
277 return &dsa_pkey_meth;
278}
279