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 unsigned int sltmp;
129 EC_KEY *ec = ctx->pkey->pkey.ec;
130
131 if (!sig) {
132 *siglen = ECDSA_size(ec);
133 return 1;
134 } else if (*siglen < (size_t)ECDSA_size(ec)) {
135 OPENSSL_PUT_ERROR(EVP, EVP_R_BUFFER_TOO_SMALL);
136 return 0;
137 }
138
139 if (!ECDSA_sign(0, tbs, tbslen, sig, &sltmp, ec)) {
140 return 0;
141 }
142 *siglen = (size_t)sltmp;
143 return 1;
144 }
145
pkey_ec_verify(EVP_PKEY_CTX * ctx,const uint8_t * sig,size_t siglen,const uint8_t * tbs,size_t tbslen)146 static int pkey_ec_verify(EVP_PKEY_CTX *ctx, const uint8_t *sig, size_t siglen,
147 const uint8_t *tbs, size_t tbslen) {
148 return ECDSA_verify(0, tbs, tbslen, sig, siglen, ctx->pkey->pkey.ec);
149 }
150
pkey_ec_derive(EVP_PKEY_CTX * ctx,uint8_t * key,size_t * keylen)151 static int pkey_ec_derive(EVP_PKEY_CTX *ctx, uint8_t *key,
152 size_t *keylen) {
153 int ret;
154 size_t outlen;
155 const EC_POINT *pubkey = NULL;
156 EC_KEY *eckey;
157
158 if (!ctx->pkey || !ctx->peerkey) {
159 OPENSSL_PUT_ERROR(EVP, EVP_R_KEYS_NOT_SET);
160 return 0;
161 }
162
163 eckey = ctx->pkey->pkey.ec;
164
165 if (!key) {
166 const EC_GROUP *group;
167 group = EC_KEY_get0_group(eckey);
168 *keylen = (EC_GROUP_get_degree(group) + 7) / 8;
169 return 1;
170 }
171 pubkey = EC_KEY_get0_public_key(ctx->peerkey->pkey.ec);
172
173 /* NB: unlike PKCS#3 DH, if *outlen is less than maximum size this is
174 * not an error, the result is truncated. */
175
176 outlen = *keylen;
177
178 ret = ECDH_compute_key(key, outlen, pubkey, eckey, 0);
179 if (ret < 0) {
180 return 0;
181 }
182 *keylen = ret;
183 return 1;
184 }
185
pkey_ec_ctrl(EVP_PKEY_CTX * ctx,int type,int p1,void * p2)186 static int pkey_ec_ctrl(EVP_PKEY_CTX *ctx, int type, int p1, void *p2) {
187 EC_PKEY_CTX *dctx = ctx->data;
188 EC_GROUP *group;
189
190 switch (type) {
191 case EVP_PKEY_CTRL_EC_PARAMGEN_CURVE_NID:
192 group = EC_GROUP_new_by_curve_name(p1);
193 if (group == NULL) {
194 OPENSSL_PUT_ERROR(EVP, EVP_R_INVALID_CURVE);
195 return 0;
196 }
197 EC_GROUP_free(dctx->gen_group);
198 dctx->gen_group = group;
199 return 1;
200
201 case EVP_PKEY_CTRL_MD:
202 if (EVP_MD_type((const EVP_MD *)p2) != NID_sha1 &&
203 EVP_MD_type((const EVP_MD *)p2) != NID_ecdsa_with_SHA1 &&
204 EVP_MD_type((const EVP_MD *)p2) != NID_sha224 &&
205 EVP_MD_type((const EVP_MD *)p2) != NID_sha256 &&
206 EVP_MD_type((const EVP_MD *)p2) != NID_sha384 &&
207 EVP_MD_type((const EVP_MD *)p2) != NID_sha512) {
208 OPENSSL_PUT_ERROR(EVP, EVP_R_INVALID_DIGEST_TYPE);
209 return 0;
210 }
211 dctx->md = p2;
212 return 1;
213
214 case EVP_PKEY_CTRL_GET_MD:
215 *(const EVP_MD **)p2 = dctx->md;
216 return 1;
217
218 case EVP_PKEY_CTRL_PEER_KEY:
219 /* Default behaviour is OK */
220 return 1;
221
222 default:
223 OPENSSL_PUT_ERROR(EVP, EVP_R_COMMAND_NOT_SUPPORTED);
224 return 0;
225 }
226 }
227
pkey_ec_paramgen(EVP_PKEY_CTX * ctx,EVP_PKEY * pkey)228 static int pkey_ec_paramgen(EVP_PKEY_CTX *ctx, EVP_PKEY *pkey) {
229 EC_KEY *ec = NULL;
230 EC_PKEY_CTX *dctx = ctx->data;
231 int ret = 0;
232
233 if (dctx->gen_group == NULL) {
234 OPENSSL_PUT_ERROR(EVP, EVP_R_NO_PARAMETERS_SET);
235 return 0;
236 }
237 ec = EC_KEY_new();
238 if (!ec) {
239 return 0;
240 }
241 ret = EC_KEY_set_group(ec, dctx->gen_group);
242 if (ret) {
243 EVP_PKEY_assign_EC_KEY(pkey, ec);
244 } else {
245 EC_KEY_free(ec);
246 }
247 return ret;
248 }
249
pkey_ec_keygen(EVP_PKEY_CTX * ctx,EVP_PKEY * pkey)250 static int pkey_ec_keygen(EVP_PKEY_CTX *ctx, EVP_PKEY *pkey) {
251 EC_KEY *ec = NULL;
252 EC_PKEY_CTX *dctx = ctx->data;
253 if (ctx->pkey == NULL && dctx->gen_group == NULL) {
254 OPENSSL_PUT_ERROR(EVP, EVP_R_NO_PARAMETERS_SET);
255 return 0;
256 }
257 ec = EC_KEY_new();
258 if (!ec) {
259 return 0;
260 }
261 EVP_PKEY_assign_EC_KEY(pkey, ec);
262 if (ctx->pkey) {
263 /* Note: if error return, pkey is freed by parent routine */
264 if (!EVP_PKEY_copy_parameters(pkey, ctx->pkey)) {
265 return 0;
266 }
267 } else {
268 if (!EC_KEY_set_group(ec, dctx->gen_group)) {
269 return 0;
270 }
271 }
272 return EC_KEY_generate_key(pkey->pkey.ec);
273 }
274
275 const EVP_PKEY_METHOD ec_pkey_meth = {
276 EVP_PKEY_EC, 0 /* flags */, pkey_ec_init,
277 pkey_ec_copy, pkey_ec_cleanup, 0 /* paramgen_init */,
278 pkey_ec_paramgen, 0 /* keygen_init */, pkey_ec_keygen,
279 0 /* sign_init */, pkey_ec_sign, 0 /* verify_init */,
280 pkey_ec_verify, 0 /* encrypt_init */, 0 /* encrypt */,
281 0 /* decrypt_init */, 0 /* decrypt */, 0 /* derive_init */,
282 pkey_ec_derive, pkey_ec_ctrl,
283 };
284