1 /*
2 * Copyright 2006-2021 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 /*
11 * DSA low level APIs are deprecated for public use, but still ok for
12 * internal use.
13 */
14 #include "internal/deprecated.h"
15
16 #include <stdio.h>
17 #include "internal/cryptlib.h"
18 #include <openssl/asn1t.h>
19 #include <openssl/x509.h>
20 #include <openssl/evp.h>
21 #include <openssl/bn.h>
22 #include "crypto/evp.h"
23 #include "dsa_local.h"
24
25 /* DSA pkey context structure */
26
27 typedef struct {
28 /* Parameter gen parameters */
29 int nbits; /* size of p in bits (default: 2048) */
30 int qbits; /* size of q in bits (default: 224) */
31 const EVP_MD *pmd; /* MD for parameter generation */
32 /* Keygen callback info */
33 int gentmp[2];
34 /* message digest */
35 const EVP_MD *md; /* MD for the signature */
36 } DSA_PKEY_CTX;
37
pkey_dsa_init(EVP_PKEY_CTX * ctx)38 static int pkey_dsa_init(EVP_PKEY_CTX *ctx)
39 {
40 DSA_PKEY_CTX *dctx = OPENSSL_malloc(sizeof(*dctx));
41
42 if (dctx == NULL)
43 return 0;
44 dctx->nbits = 2048;
45 dctx->qbits = 224;
46 dctx->pmd = NULL;
47 dctx->md = NULL;
48
49 ctx->data = dctx;
50 ctx->keygen_info = dctx->gentmp;
51 ctx->keygen_info_count = 2;
52
53 return 1;
54 }
55
pkey_dsa_copy(EVP_PKEY_CTX * dst,const EVP_PKEY_CTX * src)56 static int pkey_dsa_copy(EVP_PKEY_CTX *dst, const EVP_PKEY_CTX *src)
57 {
58 DSA_PKEY_CTX *dctx, *sctx;
59
60 if (!pkey_dsa_init(dst))
61 return 0;
62 sctx = src->data;
63 dctx = dst->data;
64 dctx->nbits = sctx->nbits;
65 dctx->qbits = sctx->qbits;
66 dctx->pmd = sctx->pmd;
67 dctx->md = sctx->md;
68 return 1;
69 }
70
pkey_dsa_cleanup(EVP_PKEY_CTX * ctx)71 static void pkey_dsa_cleanup(EVP_PKEY_CTX *ctx)
72 {
73 DSA_PKEY_CTX *dctx = ctx->data;
74 OPENSSL_free(dctx);
75 }
76
pkey_dsa_sign(EVP_PKEY_CTX * ctx,unsigned char * sig,size_t * siglen,const unsigned char * tbs,size_t tbslen)77 static int pkey_dsa_sign(EVP_PKEY_CTX *ctx, unsigned char *sig,
78 size_t *siglen, const unsigned char *tbs,
79 size_t tbslen)
80 {
81 int ret;
82 unsigned int sltmp;
83 DSA_PKEY_CTX *dctx = ctx->data;
84 /*
85 * Discard const. Its marked as const because this may be a cached copy of
86 * the "real" key. These calls don't make any modifications that need to
87 * be reflected back in the "original" key.
88 */
89 DSA *dsa = (DSA *)EVP_PKEY_get0_DSA(ctx->pkey);
90
91 if (dctx->md != NULL && tbslen != (size_t)EVP_MD_get_size(dctx->md))
92 return 0;
93
94 ret = DSA_sign(0, tbs, tbslen, sig, &sltmp, dsa);
95
96 if (ret <= 0)
97 return ret;
98 *siglen = sltmp;
99 return 1;
100 }
101
pkey_dsa_verify(EVP_PKEY_CTX * ctx,const unsigned char * sig,size_t siglen,const unsigned char * tbs,size_t tbslen)102 static int pkey_dsa_verify(EVP_PKEY_CTX *ctx,
103 const unsigned char *sig, size_t siglen,
104 const unsigned char *tbs, size_t tbslen)
105 {
106 int ret;
107 DSA_PKEY_CTX *dctx = ctx->data;
108 /*
109 * Discard const. Its marked as const because this may be a cached copy of
110 * the "real" key. These calls don't make any modifications that need to
111 * be reflected back in the "original" key.
112 */
113 DSA *dsa = (DSA *)EVP_PKEY_get0_DSA(ctx->pkey);
114
115 if (dctx->md != NULL && tbslen != (size_t)EVP_MD_get_size(dctx->md))
116 return 0;
117
118 ret = DSA_verify(0, tbs, tbslen, sig, siglen, dsa);
119
120 return ret;
121 }
122
pkey_dsa_ctrl(EVP_PKEY_CTX * ctx,int type,int p1,void * p2)123 static int pkey_dsa_ctrl(EVP_PKEY_CTX *ctx, int type, int p1, void *p2)
124 {
125 DSA_PKEY_CTX *dctx = ctx->data;
126
127 switch (type) {
128 case EVP_PKEY_CTRL_DSA_PARAMGEN_BITS:
129 if (p1 < 256)
130 return -2;
131 dctx->nbits = p1;
132 return 1;
133
134 case EVP_PKEY_CTRL_DSA_PARAMGEN_Q_BITS:
135 if (p1 != 160 && p1 != 224 && p1 && p1 != 256)
136 return -2;
137 dctx->qbits = p1;
138 return 1;
139
140 case EVP_PKEY_CTRL_DSA_PARAMGEN_MD:
141 if (EVP_MD_get_type((const EVP_MD *)p2) != NID_sha1 &&
142 EVP_MD_get_type((const EVP_MD *)p2) != NID_sha224 &&
143 EVP_MD_get_type((const EVP_MD *)p2) != NID_sha256) {
144 ERR_raise(ERR_LIB_DSA, DSA_R_INVALID_DIGEST_TYPE);
145 return 0;
146 }
147 dctx->pmd = p2;
148 return 1;
149
150 case EVP_PKEY_CTRL_MD:
151 if (EVP_MD_get_type((const EVP_MD *)p2) != NID_sha1 &&
152 EVP_MD_get_type((const EVP_MD *)p2) != NID_dsa &&
153 EVP_MD_get_type((const EVP_MD *)p2) != NID_dsaWithSHA &&
154 EVP_MD_get_type((const EVP_MD *)p2) != NID_sha224 &&
155 EVP_MD_get_type((const EVP_MD *)p2) != NID_sha256 &&
156 EVP_MD_get_type((const EVP_MD *)p2) != NID_sha384 &&
157 EVP_MD_get_type((const EVP_MD *)p2) != NID_sha512 &&
158 EVP_MD_get_type((const EVP_MD *)p2) != NID_sha3_224 &&
159 EVP_MD_get_type((const EVP_MD *)p2) != NID_sha3_256 &&
160 EVP_MD_get_type((const EVP_MD *)p2) != NID_sha3_384 &&
161 EVP_MD_get_type((const EVP_MD *)p2) != NID_sha3_512) {
162 ERR_raise(ERR_LIB_DSA, DSA_R_INVALID_DIGEST_TYPE);
163 return 0;
164 }
165 dctx->md = p2;
166 return 1;
167
168 case EVP_PKEY_CTRL_GET_MD:
169 *(const EVP_MD **)p2 = dctx->md;
170 return 1;
171
172 case EVP_PKEY_CTRL_DIGESTINIT:
173 case EVP_PKEY_CTRL_PKCS7_SIGN:
174 case EVP_PKEY_CTRL_CMS_SIGN:
175 return 1;
176
177 case EVP_PKEY_CTRL_PEER_KEY:
178 ERR_raise(ERR_LIB_DSA, EVP_R_OPERATION_NOT_SUPPORTED_FOR_THIS_KEYTYPE);
179 return -2;
180 default:
181 return -2;
182
183 }
184 }
185
pkey_dsa_ctrl_str(EVP_PKEY_CTX * ctx,const char * type,const char * value)186 static int pkey_dsa_ctrl_str(EVP_PKEY_CTX *ctx,
187 const char *type, const char *value)
188 {
189 if (strcmp(type, "dsa_paramgen_bits") == 0) {
190 int nbits;
191 nbits = atoi(value);
192 return EVP_PKEY_CTX_set_dsa_paramgen_bits(ctx, nbits);
193 }
194 if (strcmp(type, "dsa_paramgen_q_bits") == 0) {
195 int qbits = atoi(value);
196 return EVP_PKEY_CTX_set_dsa_paramgen_q_bits(ctx, qbits);
197 }
198 if (strcmp(type, "dsa_paramgen_md") == 0) {
199 const EVP_MD *md = EVP_get_digestbyname(value);
200
201 if (md == NULL) {
202 ERR_raise(ERR_LIB_DSA, DSA_R_INVALID_DIGEST_TYPE);
203 return 0;
204 }
205 return EVP_PKEY_CTX_set_dsa_paramgen_md(ctx, md);
206 }
207 return -2;
208 }
209
pkey_dsa_paramgen(EVP_PKEY_CTX * ctx,EVP_PKEY * pkey)210 static int pkey_dsa_paramgen(EVP_PKEY_CTX *ctx, EVP_PKEY *pkey)
211 {
212 DSA *dsa = NULL;
213 DSA_PKEY_CTX *dctx = ctx->data;
214 BN_GENCB *pcb;
215 int ret, res;
216
217 if (ctx->pkey_gencb) {
218 pcb = BN_GENCB_new();
219 if (pcb == NULL)
220 return 0;
221 evp_pkey_set_cb_translate(pcb, ctx);
222 } else
223 pcb = NULL;
224 dsa = DSA_new();
225 if (dsa == NULL) {
226 BN_GENCB_free(pcb);
227 return 0;
228 }
229 if (dctx->md != NULL)
230 ossl_ffc_set_digest(&dsa->params, EVP_MD_get0_name(dctx->md), NULL);
231
232 ret = ossl_ffc_params_FIPS186_4_generate(NULL, &dsa->params,
233 FFC_PARAM_TYPE_DSA, dctx->nbits,
234 dctx->qbits, &res, pcb);
235 BN_GENCB_free(pcb);
236 if (ret > 0)
237 EVP_PKEY_assign_DSA(pkey, dsa);
238 else
239 DSA_free(dsa);
240 return ret;
241 }
242
pkey_dsa_keygen(EVP_PKEY_CTX * ctx,EVP_PKEY * pkey)243 static int pkey_dsa_keygen(EVP_PKEY_CTX *ctx, EVP_PKEY *pkey)
244 {
245 DSA *dsa = NULL;
246
247 if (ctx->pkey == NULL) {
248 ERR_raise(ERR_LIB_DSA, DSA_R_NO_PARAMETERS_SET);
249 return 0;
250 }
251 dsa = DSA_new();
252 if (dsa == NULL)
253 return 0;
254 EVP_PKEY_assign_DSA(pkey, dsa);
255 /* Note: if error return, pkey is freed by parent routine */
256 if (!EVP_PKEY_copy_parameters(pkey, ctx->pkey))
257 return 0;
258 return DSA_generate_key((DSA *)EVP_PKEY_get0_DSA(pkey));
259 }
260
261 static const EVP_PKEY_METHOD dsa_pkey_meth = {
262 EVP_PKEY_DSA,
263 EVP_PKEY_FLAG_AUTOARGLEN,
264 pkey_dsa_init,
265 pkey_dsa_copy,
266 pkey_dsa_cleanup,
267
268 0,
269 pkey_dsa_paramgen,
270
271 0,
272 pkey_dsa_keygen,
273
274 0,
275 pkey_dsa_sign,
276
277 0,
278 pkey_dsa_verify,
279
280 0, 0,
281
282 0, 0, 0, 0,
283
284 0, 0,
285
286 0, 0,
287
288 0, 0,
289
290 pkey_dsa_ctrl,
291 pkey_dsa_ctrl_str
292 };
293
ossl_dsa_pkey_method(void)294 const EVP_PKEY_METHOD *ossl_dsa_pkey_method(void)
295 {
296 return &dsa_pkey_meth;
297 }
298