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 #include <openssl/evp.h>
57
58 #include <string.h>
59
60 #include <openssl/asn1.h>
61 #include <openssl/bn.h>
62 #include <openssl/buf.h>
63 #include <openssl/digest.h>
64 #include <openssl/ec.h>
65 #include <openssl/ec_key.h>
66 #include <openssl/ecdh.h>
67 #include <openssl/ecdsa.h>
68 #include <openssl/err.h>
69 #include <openssl/mem.h>
70 #include <openssl/obj.h>
71
72 #include "internal.h"
73 #include "../ec/internal.h"
74
75
76 typedef struct {
77 /* Key and paramgen group */
78 EC_GROUP *gen_group;
79 /* message digest */
80 const EVP_MD *md;
81 } EC_PKEY_CTX;
82
83
pkey_ec_init(EVP_PKEY_CTX * ctx)84 static int pkey_ec_init(EVP_PKEY_CTX *ctx) {
85 EC_PKEY_CTX *dctx;
86 dctx = OPENSSL_malloc(sizeof(EC_PKEY_CTX));
87 if (!dctx) {
88 return 0;
89 }
90 memset(dctx, 0, sizeof(EC_PKEY_CTX));
91
92 ctx->data = dctx;
93
94 return 1;
95 }
96
pkey_ec_copy(EVP_PKEY_CTX * dst,EVP_PKEY_CTX * src)97 static int pkey_ec_copy(EVP_PKEY_CTX *dst, EVP_PKEY_CTX *src) {
98 EC_PKEY_CTX *dctx, *sctx;
99 if (!pkey_ec_init(dst)) {
100 return 0;
101 }
102 sctx = src->data;
103 dctx = dst->data;
104
105 if (sctx->gen_group) {
106 dctx->gen_group = EC_GROUP_dup(sctx->gen_group);
107 if (!dctx->gen_group) {
108 return 0;
109 }
110 }
111 dctx->md = sctx->md;
112
113 return 1;
114 }
115
pkey_ec_cleanup(EVP_PKEY_CTX * ctx)116 static void pkey_ec_cleanup(EVP_PKEY_CTX *ctx) {
117 EC_PKEY_CTX *dctx = ctx->data;
118 if (!dctx) {
119 return;
120 }
121
122 EC_GROUP_free(dctx->gen_group);
123 OPENSSL_free(dctx);
124 }
125
pkey_ec_sign(EVP_PKEY_CTX * ctx,uint8_t * sig,size_t * siglen,const uint8_t * tbs,size_t tbslen)126 static int pkey_ec_sign(EVP_PKEY_CTX *ctx, uint8_t *sig, size_t *siglen,
127 const uint8_t *tbs, size_t tbslen) {
128 int type;
129 unsigned int sltmp;
130 EC_PKEY_CTX *dctx = ctx->data;
131 EC_KEY *ec = ctx->pkey->pkey.ec;
132
133 if (!sig) {
134 *siglen = ECDSA_size(ec);
135 return 1;
136 } else if (*siglen < (size_t)ECDSA_size(ec)) {
137 OPENSSL_PUT_ERROR(EVP, pkey_ec_sign, EVP_R_BUFFER_TOO_SMALL);
138 return 0;
139 }
140
141 type = NID_sha1;
142 if (dctx->md) {
143 type = EVP_MD_type(dctx->md);
144 }
145
146 if (!ECDSA_sign(type, tbs, tbslen, sig, &sltmp, ec)) {
147 return 0;
148 }
149 *siglen = (size_t)sltmp;
150 return 1;
151 }
152
pkey_ec_verify(EVP_PKEY_CTX * ctx,const uint8_t * sig,size_t siglen,const uint8_t * tbs,size_t tbslen)153 static int pkey_ec_verify(EVP_PKEY_CTX *ctx, const uint8_t *sig, size_t siglen,
154 const uint8_t *tbs, size_t tbslen) {
155 int type;
156 EC_PKEY_CTX *dctx = ctx->data;
157 EC_KEY *ec = ctx->pkey->pkey.ec;
158
159 type = NID_sha1;
160 if (dctx->md) {
161 type = EVP_MD_type(dctx->md);
162 }
163
164 return ECDSA_verify(type, tbs, tbslen, sig, siglen, ec);
165 }
166
pkey_ec_derive(EVP_PKEY_CTX * ctx,uint8_t * key,size_t * keylen)167 static int pkey_ec_derive(EVP_PKEY_CTX *ctx, uint8_t *key,
168 size_t *keylen) {
169 int ret;
170 size_t outlen;
171 const EC_POINT *pubkey = NULL;
172 EC_KEY *eckey;
173
174 if (!ctx->pkey || !ctx->peerkey) {
175 OPENSSL_PUT_ERROR(EVP, pkey_ec_derive, EVP_R_KEYS_NOT_SET);
176 return 0;
177 }
178
179 eckey = ctx->pkey->pkey.ec;
180
181 if (!key) {
182 const EC_GROUP *group;
183 group = EC_KEY_get0_group(eckey);
184 *keylen = (EC_GROUP_get_degree(group) + 7) / 8;
185 return 1;
186 }
187 pubkey = EC_KEY_get0_public_key(ctx->peerkey->pkey.ec);
188
189 /* NB: unlike PKCS#3 DH, if *outlen is less than maximum size this is
190 * not an error, the result is truncated. */
191
192 outlen = *keylen;
193
194 ret = ECDH_compute_key(key, outlen, pubkey, eckey, 0);
195 if (ret < 0) {
196 return 0;
197 }
198 *keylen = ret;
199 return 1;
200 }
201
pkey_ec_ctrl(EVP_PKEY_CTX * ctx,int type,int p1,void * p2)202 static int pkey_ec_ctrl(EVP_PKEY_CTX *ctx, int type, int p1, void *p2) {
203 EC_PKEY_CTX *dctx = ctx->data;
204 EC_GROUP *group;
205
206 switch (type) {
207 case EVP_PKEY_CTRL_EC_PARAMGEN_CURVE_NID:
208 group = EC_GROUP_new_by_curve_name(p1);
209 if (group == NULL) {
210 OPENSSL_PUT_ERROR(EVP, pkey_ec_ctrl, EVP_R_INVALID_CURVE);
211 return 0;
212 }
213 EC_GROUP_free(dctx->gen_group);
214 dctx->gen_group = group;
215 return 1;
216
217 case EVP_PKEY_CTRL_MD:
218 if (EVP_MD_type((const EVP_MD *)p2) != NID_sha1 &&
219 EVP_MD_type((const EVP_MD *)p2) != NID_ecdsa_with_SHA1 &&
220 EVP_MD_type((const EVP_MD *)p2) != NID_sha224 &&
221 EVP_MD_type((const EVP_MD *)p2) != NID_sha256 &&
222 EVP_MD_type((const EVP_MD *)p2) != NID_sha384 &&
223 EVP_MD_type((const EVP_MD *)p2) != NID_sha512) {
224 OPENSSL_PUT_ERROR(EVP, pkey_ec_ctrl, EVP_R_INVALID_DIGEST_TYPE);
225 return 0;
226 }
227 dctx->md = p2;
228 return 1;
229
230 case EVP_PKEY_CTRL_GET_MD:
231 *(const EVP_MD **)p2 = dctx->md;
232 return 1;
233
234 case EVP_PKEY_CTRL_PEER_KEY:
235 /* Default behaviour is OK */
236 case EVP_PKEY_CTRL_DIGESTINIT:
237 return 1;
238
239 default:
240 OPENSSL_PUT_ERROR(EVP, pkey_ec_ctrl, EVP_R_COMMAND_NOT_SUPPORTED);
241 return 0;
242 }
243 }
244
pkey_ec_paramgen(EVP_PKEY_CTX * ctx,EVP_PKEY * pkey)245 static int pkey_ec_paramgen(EVP_PKEY_CTX *ctx, EVP_PKEY *pkey) {
246 EC_KEY *ec = NULL;
247 EC_PKEY_CTX *dctx = ctx->data;
248 int ret = 0;
249
250 if (dctx->gen_group == NULL) {
251 OPENSSL_PUT_ERROR(EVP, pkey_ec_paramgen, EVP_R_NO_PARAMETERS_SET);
252 return 0;
253 }
254 ec = EC_KEY_new();
255 if (!ec) {
256 return 0;
257 }
258 ret = EC_KEY_set_group(ec, dctx->gen_group);
259 if (ret) {
260 EVP_PKEY_assign_EC_KEY(pkey, ec);
261 } else {
262 EC_KEY_free(ec);
263 }
264 return ret;
265 }
266
pkey_ec_keygen(EVP_PKEY_CTX * ctx,EVP_PKEY * pkey)267 static int pkey_ec_keygen(EVP_PKEY_CTX *ctx, EVP_PKEY *pkey) {
268 EC_KEY *ec = NULL;
269 EC_PKEY_CTX *dctx = ctx->data;
270 if (ctx->pkey == NULL && dctx->gen_group == NULL) {
271 OPENSSL_PUT_ERROR(EVP, pkey_ec_keygen, EVP_R_NO_PARAMETERS_SET);
272 return 0;
273 }
274 ec = EC_KEY_new();
275 if (!ec) {
276 return 0;
277 }
278 EVP_PKEY_assign_EC_KEY(pkey, ec);
279 if (ctx->pkey) {
280 /* Note: if error return, pkey is freed by parent routine */
281 if (!EVP_PKEY_copy_parameters(pkey, ctx->pkey)) {
282 return 0;
283 }
284 } else {
285 if (!EC_KEY_set_group(ec, dctx->gen_group)) {
286 return 0;
287 }
288 }
289 return EC_KEY_generate_key(pkey->pkey.ec);
290 }
291
292 const EVP_PKEY_METHOD ec_pkey_meth = {
293 EVP_PKEY_EC, 0 /* flags */, pkey_ec_init,
294 pkey_ec_copy, pkey_ec_cleanup, 0 /* paramgen_init */,
295 pkey_ec_paramgen, 0 /* keygen_init */, pkey_ec_keygen,
296 0 /* sign_init */, pkey_ec_sign, 0 /* verify_init */,
297 pkey_ec_verify, 0 /* signctx_init */, 0 /* signctx */,
298 0 /* verifyctx_init */, 0 /* verifyctx */, 0 /* encrypt_init */,
299 0 /* encrypt */, 0 /* decrypt_init */, 0 /* decrypt */,
300 0 /* derive_init */, pkey_ec_derive, pkey_ec_ctrl,
301 };
302