1 /*
2 * Copyright 2006-2024 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, md_size;
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) {
92 md_size = EVP_MD_get_size(dctx->md);
93 if (md_size <= 0)
94 return 0;
95 if (tbslen != (size_t)md_size)
96 return 0;
97 }
98
99 ret = DSA_sign(0, tbs, tbslen, sig, &sltmp, dsa);
100
101 if (ret <= 0)
102 return ret;
103 *siglen = sltmp;
104 return 1;
105 }
106
pkey_dsa_verify(EVP_PKEY_CTX * ctx,const unsigned char * sig,size_t siglen,const unsigned char * tbs,size_t tbslen)107 static int pkey_dsa_verify(EVP_PKEY_CTX *ctx,
108 const unsigned char *sig, size_t siglen,
109 const unsigned char *tbs, size_t tbslen)
110 {
111 int ret, md_size;
112 DSA_PKEY_CTX *dctx = ctx->data;
113 /*
114 * Discard const. Its marked as const because this may be a cached copy of
115 * the "real" key. These calls don't make any modifications that need to
116 * be reflected back in the "original" key.
117 */
118 DSA *dsa = (DSA *)EVP_PKEY_get0_DSA(ctx->pkey);
119
120 if (dctx->md != NULL) {
121 md_size = EVP_MD_get_size(dctx->md);
122 if (md_size <= 0)
123 return 0;
124 if (tbslen != (size_t)md_size)
125 return 0;
126 }
127
128 ret = DSA_verify(0, tbs, tbslen, sig, siglen, dsa);
129
130 return ret;
131 }
132
pkey_dsa_ctrl(EVP_PKEY_CTX * ctx,int type,int p1,void * p2)133 static int pkey_dsa_ctrl(EVP_PKEY_CTX *ctx, int type, int p1, void *p2)
134 {
135 DSA_PKEY_CTX *dctx = ctx->data;
136
137 switch (type) {
138 case EVP_PKEY_CTRL_DSA_PARAMGEN_BITS:
139 if (p1 < 256)
140 return -2;
141 dctx->nbits = p1;
142 return 1;
143
144 case EVP_PKEY_CTRL_DSA_PARAMGEN_Q_BITS:
145 if (p1 != 160 && p1 != 224 && p1 && p1 != 256)
146 return -2;
147 dctx->qbits = p1;
148 return 1;
149
150 case EVP_PKEY_CTRL_DSA_PARAMGEN_MD:
151 if (EVP_MD_get_type((const EVP_MD *)p2) != NID_sha1 &&
152 EVP_MD_get_type((const EVP_MD *)p2) != NID_sha224 &&
153 EVP_MD_get_type((const EVP_MD *)p2) != NID_sha256) {
154 ERR_raise(ERR_LIB_DSA, DSA_R_INVALID_DIGEST_TYPE);
155 return 0;
156 }
157 dctx->pmd = p2;
158 return 1;
159
160 case EVP_PKEY_CTRL_MD:
161 if (EVP_MD_get_type((const EVP_MD *)p2) != NID_sha1 &&
162 EVP_MD_get_type((const EVP_MD *)p2) != NID_dsa &&
163 EVP_MD_get_type((const EVP_MD *)p2) != NID_dsaWithSHA &&
164 EVP_MD_get_type((const EVP_MD *)p2) != NID_sha224 &&
165 EVP_MD_get_type((const EVP_MD *)p2) != NID_sha256 &&
166 EVP_MD_get_type((const EVP_MD *)p2) != NID_sha384 &&
167 EVP_MD_get_type((const EVP_MD *)p2) != NID_sha512 &&
168 EVP_MD_get_type((const EVP_MD *)p2) != NID_sha3_224 &&
169 EVP_MD_get_type((const EVP_MD *)p2) != NID_sha3_256 &&
170 EVP_MD_get_type((const EVP_MD *)p2) != NID_sha3_384 &&
171 EVP_MD_get_type((const EVP_MD *)p2) != NID_sha3_512) {
172 ERR_raise(ERR_LIB_DSA, DSA_R_INVALID_DIGEST_TYPE);
173 return 0;
174 }
175 dctx->md = p2;
176 return 1;
177
178 case EVP_PKEY_CTRL_GET_MD:
179 *(const EVP_MD **)p2 = dctx->md;
180 return 1;
181
182 case EVP_PKEY_CTRL_DIGESTINIT:
183 case EVP_PKEY_CTRL_PKCS7_SIGN:
184 case EVP_PKEY_CTRL_CMS_SIGN:
185 return 1;
186
187 case EVP_PKEY_CTRL_PEER_KEY:
188 ERR_raise(ERR_LIB_DSA, EVP_R_OPERATION_NOT_SUPPORTED_FOR_THIS_KEYTYPE);
189 return -2;
190 default:
191 return -2;
192
193 }
194 }
195
pkey_dsa_ctrl_str(EVP_PKEY_CTX * ctx,const char * type,const char * value)196 static int pkey_dsa_ctrl_str(EVP_PKEY_CTX *ctx,
197 const char *type, const char *value)
198 {
199 if (strcmp(type, "dsa_paramgen_bits") == 0) {
200 int nbits;
201 nbits = atoi(value);
202 return EVP_PKEY_CTX_set_dsa_paramgen_bits(ctx, nbits);
203 }
204 if (strcmp(type, "dsa_paramgen_q_bits") == 0) {
205 int qbits = atoi(value);
206 return EVP_PKEY_CTX_set_dsa_paramgen_q_bits(ctx, qbits);
207 }
208 if (strcmp(type, "dsa_paramgen_md") == 0) {
209 const EVP_MD *md = EVP_get_digestbyname(value);
210
211 if (md == NULL) {
212 ERR_raise(ERR_LIB_DSA, DSA_R_INVALID_DIGEST_TYPE);
213 return 0;
214 }
215 return EVP_PKEY_CTX_set_dsa_paramgen_md(ctx, md);
216 }
217 return -2;
218 }
219
pkey_dsa_paramgen(EVP_PKEY_CTX * ctx,EVP_PKEY * pkey)220 static int pkey_dsa_paramgen(EVP_PKEY_CTX *ctx, EVP_PKEY *pkey)
221 {
222 DSA *dsa = NULL;
223 DSA_PKEY_CTX *dctx = ctx->data;
224 BN_GENCB *pcb;
225 int ret, res;
226
227 if (ctx->pkey_gencb) {
228 pcb = BN_GENCB_new();
229 if (pcb == NULL)
230 return 0;
231 evp_pkey_set_cb_translate(pcb, ctx);
232 } else
233 pcb = NULL;
234 dsa = DSA_new();
235 if (dsa == NULL) {
236 BN_GENCB_free(pcb);
237 return 0;
238 }
239 if (dctx->md != NULL)
240 ossl_ffc_set_digest(&dsa->params, EVP_MD_get0_name(dctx->md), NULL);
241
242 ret = ossl_ffc_params_FIPS186_4_generate(NULL, &dsa->params,
243 FFC_PARAM_TYPE_DSA, dctx->nbits,
244 dctx->qbits, &res, pcb);
245 BN_GENCB_free(pcb);
246 if (ret > 0)
247 EVP_PKEY_assign_DSA(pkey, dsa);
248 else
249 DSA_free(dsa);
250 return ret;
251 }
252
pkey_dsa_keygen(EVP_PKEY_CTX * ctx,EVP_PKEY * pkey)253 static int pkey_dsa_keygen(EVP_PKEY_CTX *ctx, EVP_PKEY *pkey)
254 {
255 DSA *dsa = NULL;
256
257 if (ctx->pkey == NULL) {
258 ERR_raise(ERR_LIB_DSA, DSA_R_NO_PARAMETERS_SET);
259 return 0;
260 }
261 dsa = DSA_new();
262 if (dsa == NULL)
263 return 0;
264 EVP_PKEY_assign_DSA(pkey, dsa);
265 /* Note: if error return, pkey is freed by parent routine */
266 if (!EVP_PKEY_copy_parameters(pkey, ctx->pkey))
267 return 0;
268 return DSA_generate_key((DSA *)EVP_PKEY_get0_DSA(pkey));
269 }
270
271 static const EVP_PKEY_METHOD dsa_pkey_meth = {
272 EVP_PKEY_DSA,
273 EVP_PKEY_FLAG_AUTOARGLEN,
274 pkey_dsa_init,
275 pkey_dsa_copy,
276 pkey_dsa_cleanup,
277
278 0,
279 pkey_dsa_paramgen,
280
281 0,
282 pkey_dsa_keygen,
283
284 0,
285 pkey_dsa_sign,
286
287 0,
288 pkey_dsa_verify,
289
290 0, 0,
291
292 0, 0, 0, 0,
293
294 0, 0,
295
296 0, 0,
297
298 0, 0,
299
300 pkey_dsa_ctrl,
301 pkey_dsa_ctrl_str
302 };
303
ossl_dsa_pkey_method(void)304 const EVP_PKEY_METHOD *ossl_dsa_pkey_method(void)
305 {
306 return &dsa_pkey_meth;
307 }
308