1 /* Written by Dr Stephen N Henson (steve@openssl.org) for the OpenSSL
2 * project 2006.
3 */
4 /* ====================================================================
5 * Copyright (c) 2006 The OpenSSL Project. All rights reserved.
6 *
7 * Redistribution and use in source and binary forms, with or without
8 * modification, are permitted provided that the following conditions
9 * are met:
10 *
11 * 1. Redistributions of source code must retain the above copyright
12 * notice, this list of conditions and the following disclaimer.
13 *
14 * 2. Redistributions in binary form must reproduce the above copyright
15 * notice, this list of conditions and the following disclaimer in
16 * the documentation and/or other materials provided with the
17 * distribution.
18 *
19 * 3. All advertising materials mentioning features or use of this
20 * software must display the following acknowledgment:
21 * "This product includes software developed by the OpenSSL Project
22 * for use in the OpenSSL Toolkit. (http://www.OpenSSL.org/)"
23 *
24 * 4. The names "OpenSSL Toolkit" and "OpenSSL Project" must not be used to
25 * endorse or promote products derived from this software without
26 * prior written permission. For written permission, please contact
27 * licensing@OpenSSL.org.
28 *
29 * 5. Products derived from this software may not be called "OpenSSL"
30 * nor may "OpenSSL" appear in their names without prior written
31 * permission of the OpenSSL Project.
32 *
33 * 6. Redistributions of any form whatsoever must retain the following
34 * acknowledgment:
35 * "This product includes software developed by the OpenSSL Project
36 * for use in the OpenSSL Toolkit (http://www.OpenSSL.org/)"
37 *
38 * THIS SOFTWARE IS PROVIDED BY THE OpenSSL PROJECT ``AS IS'' AND ANY
39 * EXPRESSED OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
40 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR
41 * PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE OpenSSL PROJECT OR
42 * ITS CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
43 * SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT
44 * NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES;
45 * LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
46 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT,
47 * STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE)
48 * ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED
49 * OF THE POSSIBILITY OF SUCH DAMAGE.
50 * ====================================================================
51 *
52 * This product includes cryptographic software written by Eric Young
53 * (eay@cryptsoft.com). This product includes software written by Tim
54 * Hudson (tjh@cryptsoft.com).
55 *
56 */
57
58 #include <stdio.h>
59 #include "cryptlib.h"
60 #include <openssl/asn1t.h>
61 #include <openssl/x509.h>
62 #include <openssl/evp.h>
63 #include <openssl/dh.h>
64 #include <openssl/bn.h>
65 #include "evp_locl.h"
66
67 /* DH pkey context structure */
68
69 typedef struct
70 {
71 /* Parameter gen parameters */
72 int prime_len;
73 int generator;
74 int use_dsa;
75 /* Keygen callback info */
76 int gentmp[2];
77 /* message digest */
78 } DH_PKEY_CTX;
79
80 static int pkey_dh_init(EVP_PKEY_CTX *ctx)
81 {
82 DH_PKEY_CTX *dctx;
83 dctx = OPENSSL_malloc(sizeof(DH_PKEY_CTX));
84 if (!dctx)
85 return 0;
86 dctx->prime_len = 1024;
87 dctx->generator = 2;
88 dctx->use_dsa = 0;
89
90 ctx->data = dctx;
91 ctx->keygen_info = dctx->gentmp;
92 ctx->keygen_info_count = 2;
93
94 return 1;
95 }
96
97 static int pkey_dh_copy(EVP_PKEY_CTX *dst, EVP_PKEY_CTX *src)
98 {
99 DH_PKEY_CTX *dctx, *sctx;
100 if (!pkey_dh_init(dst))
101 return 0;
102 sctx = src->data;
103 dctx = dst->data;
104 dctx->prime_len = sctx->prime_len;
105 dctx->generator = sctx->generator;
106 dctx->use_dsa = sctx->use_dsa;
107 return 1;
108 }
109
110 static void pkey_dh_cleanup(EVP_PKEY_CTX *ctx)
111 {
112 DH_PKEY_CTX *dctx = ctx->data;
113 if (dctx)
114 OPENSSL_free(dctx);
115 }
116
117 static int pkey_dh_ctrl(EVP_PKEY_CTX *ctx, int type, int p1, void *p2)
118 {
119 DH_PKEY_CTX *dctx = ctx->data;
120 switch (type)
121 {
122 case EVP_PKEY_CTRL_DH_PARAMGEN_PRIME_LEN:
123 if (p1 < 256)
124 return -2;
125 dctx->prime_len = p1;
126 return 1;
127
128 case EVP_PKEY_CTRL_DH_PARAMGEN_GENERATOR:
129 dctx->generator = p1;
130 return 1;
131
132 case EVP_PKEY_CTRL_PEER_KEY:
133 /* Default behaviour is OK */
134 return 1;
135
136 default:
137 return -2;
138
139 }
140 }
141
142
143 static int pkey_dh_ctrl_str(EVP_PKEY_CTX *ctx,
144 const char *type, const char *value)
145 {
146 if (!strcmp(type, "dh_paramgen_prime_len"))
147 {
148 int len;
149 len = atoi(value);
150 return EVP_PKEY_CTX_set_dh_paramgen_prime_len(ctx, len);
151 }
152 if (!strcmp(type, "dh_paramgen_generator"))
153 {
154 int len;
155 len = atoi(value);
156 return EVP_PKEY_CTX_set_dh_paramgen_generator(ctx, len);
157 }
158 return -2;
159 }
160
161 static int pkey_dh_paramgen(EVP_PKEY_CTX *ctx, EVP_PKEY *pkey)
162 {
163 DH *dh = NULL;
164 DH_PKEY_CTX *dctx = ctx->data;
165 BN_GENCB *pcb, cb;
166 int ret;
167 if (ctx->pkey_gencb)
168 {
169 pcb = &cb;
170 evp_pkey_set_cb_translate(pcb, ctx);
171 }
172 else
173 pcb = NULL;
174 dh = DH_new();
175 if (!dh)
176 return 0;
177 ret = DH_generate_parameters_ex(dh,
178 dctx->prime_len, dctx->generator, pcb);
179 if (ret)
180 EVP_PKEY_assign_DH(pkey, dh);
181 else
182 DH_free(dh);
183 return ret;
184 }
185
186 static int pkey_dh_keygen(EVP_PKEY_CTX *ctx, EVP_PKEY *pkey)
187 {
188 DH *dh = NULL;
189 if (ctx->pkey == NULL)
190 {
191 DHerr(DH_F_PKEY_DH_KEYGEN, DH_R_NO_PARAMETERS_SET);
192 return 0;
193 }
194 dh = DH_new();
195 if (!dh)
196 return 0;
197 EVP_PKEY_assign_DH(pkey, dh);
198 /* Note: if error return, pkey is freed by parent routine */
199 if (!EVP_PKEY_copy_parameters(pkey, ctx->pkey))
200 return 0;
201 return DH_generate_key(pkey->pkey.dh);
202 }
203
204 static int pkey_dh_derive(EVP_PKEY_CTX *ctx, unsigned char *key, size_t *keylen)
205 {
206 int ret;
207 if (!ctx->pkey || !ctx->peerkey)
208 {
209 DHerr(DH_F_PKEY_DH_DERIVE, DH_R_KEYS_NOT_SET);
210 return 0;
211 }
212 ret = DH_compute_key(key, ctx->peerkey->pkey.dh->pub_key,
213 ctx->pkey->pkey.dh);
214 if (ret < 0)
215 return ret;
216 *keylen = ret;
217 return 1;
218 }
219
220 const EVP_PKEY_METHOD dh_pkey_meth =
221 {
222 EVP_PKEY_DH,
223 EVP_PKEY_FLAG_AUTOARGLEN,
224 pkey_dh_init,
225 pkey_dh_copy,
226 pkey_dh_cleanup,
227
228 0,
229 pkey_dh_paramgen,
230
231 0,
232 pkey_dh_keygen,
233
234 0,
235 0,
236
237 0,
238 0,
239
240 0,0,
241
242 0,0,0,0,
243
244 0,0,
245
246 0,0,
247
248 0,
249 pkey_dh_derive,
250
251 pkey_dh_ctrl,
252 pkey_dh_ctrl_str
253
254 };