1 /* Originally written by Bodo Moeller for the OpenSSL project.
2 * ====================================================================
3 * Copyright (c) 1998-2005 The OpenSSL Project. All rights reserved.
4 *
5 * Redistribution and use in source and binary forms, with or without
6 * modification, are permitted provided that the following conditions
7 * are met:
8 *
9 * 1. Redistributions of source code must retain the above copyright
10 * notice, this list of conditions and the following disclaimer.
11 *
12 * 2. Redistributions in binary form must reproduce the above copyright
13 * notice, this list of conditions and the following disclaimer in
14 * the documentation and/or other materials provided with the
15 * distribution.
16 *
17 * 3. All advertising materials mentioning features or use of this
18 * software must display the following acknowledgment:
19 * "This product includes software developed by the OpenSSL Project
20 * for use in the OpenSSL Toolkit. (http://www.openssl.org/)"
21 *
22 * 4. The names "OpenSSL Toolkit" and "OpenSSL Project" must not be used to
23 * endorse or promote products derived from this software without
24 * prior written permission. For written permission, please contact
25 * openssl-core@openssl.org.
26 *
27 * 5. Products derived from this software may not be called "OpenSSL"
28 * nor may "OpenSSL" appear in their names without prior written
29 * permission of the OpenSSL Project.
30 *
31 * 6. Redistributions of any form whatsoever must retain the following
32 * acknowledgment:
33 * "This product includes software developed by the OpenSSL Project
34 * for use in the OpenSSL Toolkit (http://www.openssl.org/)"
35 *
36 * THIS SOFTWARE IS PROVIDED BY THE OpenSSL PROJECT ``AS IS'' AND ANY
37 * EXPRESSED OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
38 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR
39 * PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE OpenSSL PROJECT OR
40 * ITS CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
41 * SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT
42 * NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES;
43 * LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
44 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT,
45 * STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE)
46 * ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED
47 * OF THE POSSIBILITY OF SUCH DAMAGE.
48 * ====================================================================
49 *
50 * This product includes cryptographic software written by Eric Young
51 * (eay@cryptsoft.com). This product includes software written by Tim
52 * Hudson (tjh@cryptsoft.com).
53 *
54 */
55 /* ====================================================================
56 * Copyright 2002 Sun Microsystems, Inc. ALL RIGHTS RESERVED.
57 *
58 * Portions of the attached software ("Contribution") are developed by
59 * SUN MICROSYSTEMS, INC., and are contributed to the OpenSSL project.
60 *
61 * The Contribution is licensed pursuant to the OpenSSL open source
62 * license provided above.
63 *
64 * The elliptic curve binary polynomial software is originally written by
65 * Sheueling Chang Shantz and Douglas Stebila of Sun Microsystems
66 * Laboratories. */
67
68 #include <openssl/ec_key.h>
69
70 #include <string.h>
71
72 #include <openssl/ec.h>
73 #include <openssl/engine.h>
74 #include <openssl/err.h>
75 #include <openssl/ex_data.h>
76 #include <openssl/mem.h>
77 #include <openssl/thread.h>
78
79 #include "internal.h"
80 #include "../internal.h"
81
82
83 static CRYPTO_EX_DATA_CLASS g_ex_data_class = CRYPTO_EX_DATA_CLASS_INIT;
84
EC_KEY_new(void)85 EC_KEY *EC_KEY_new(void) { return EC_KEY_new_method(NULL); }
86
EC_KEY_new_method(const ENGINE * engine)87 EC_KEY *EC_KEY_new_method(const ENGINE *engine) {
88 EC_KEY *ret = OPENSSL_malloc(sizeof(EC_KEY));
89 if (ret == NULL) {
90 OPENSSL_PUT_ERROR(EC, ERR_R_MALLOC_FAILURE);
91 return NULL;
92 }
93
94 OPENSSL_memset(ret, 0, sizeof(EC_KEY));
95
96 if (engine) {
97 ret->ecdsa_meth = ENGINE_get_ECDSA_method(engine);
98 }
99 if (ret->ecdsa_meth) {
100 METHOD_ref(ret->ecdsa_meth);
101 }
102
103 ret->conv_form = POINT_CONVERSION_UNCOMPRESSED;
104 ret->references = 1;
105
106 CRYPTO_new_ex_data(&ret->ex_data);
107
108 if (ret->ecdsa_meth && ret->ecdsa_meth->init && !ret->ecdsa_meth->init(ret)) {
109 CRYPTO_free_ex_data(&g_ex_data_class, ret, &ret->ex_data);
110 if (ret->ecdsa_meth) {
111 METHOD_unref(ret->ecdsa_meth);
112 }
113 OPENSSL_free(ret);
114 return NULL;
115 }
116
117 return ret;
118 }
119
EC_KEY_new_by_curve_name(int nid)120 EC_KEY *EC_KEY_new_by_curve_name(int nid) {
121 EC_KEY *ret = EC_KEY_new();
122 if (ret == NULL) {
123 OPENSSL_PUT_ERROR(EC, ERR_R_MALLOC_FAILURE);
124 return NULL;
125 }
126 ret->group = EC_GROUP_new_by_curve_name(nid);
127 if (ret->group == NULL) {
128 EC_KEY_free(ret);
129 return NULL;
130 }
131 return ret;
132 }
133
EC_KEY_free(EC_KEY * r)134 void EC_KEY_free(EC_KEY *r) {
135 if (r == NULL) {
136 return;
137 }
138
139 if (!CRYPTO_refcount_dec_and_test_zero(&r->references)) {
140 return;
141 }
142
143 if (r->ecdsa_meth) {
144 if (r->ecdsa_meth->finish) {
145 r->ecdsa_meth->finish(r);
146 }
147 METHOD_unref(r->ecdsa_meth);
148 }
149
150 EC_GROUP_free(r->group);
151 EC_POINT_free(r->pub_key);
152 BN_clear_free(r->priv_key);
153
154 CRYPTO_free_ex_data(&g_ex_data_class, r, &r->ex_data);
155
156 OPENSSL_cleanse((void *)r, sizeof(EC_KEY));
157 OPENSSL_free(r);
158 }
159
EC_KEY_copy(EC_KEY * dest,const EC_KEY * src)160 EC_KEY *EC_KEY_copy(EC_KEY *dest, const EC_KEY *src) {
161 if (dest == NULL || src == NULL) {
162 OPENSSL_PUT_ERROR(EC, ERR_R_PASSED_NULL_PARAMETER);
163 return NULL;
164 }
165 /* Copy the parameters. */
166 if (src->group) {
167 /* TODO(fork): duplicating the group seems wasteful. */
168 EC_GROUP_free(dest->group);
169 dest->group = EC_GROUP_dup(src->group);
170 if (dest->group == NULL) {
171 return NULL;
172 }
173 }
174
175 /* Copy the public key. */
176 if (src->pub_key && src->group) {
177 EC_POINT_free(dest->pub_key);
178 dest->pub_key = EC_POINT_dup(src->pub_key, src->group);
179 if (dest->pub_key == NULL) {
180 return NULL;
181 }
182 }
183
184 /* copy the private key */
185 if (src->priv_key) {
186 if (dest->priv_key == NULL) {
187 dest->priv_key = BN_new();
188 if (dest->priv_key == NULL) {
189 return NULL;
190 }
191 }
192 if (!BN_copy(dest->priv_key, src->priv_key)) {
193 return NULL;
194 }
195 }
196 /* copy method/extra data */
197 if (src->ecdsa_meth) {
198 METHOD_unref(dest->ecdsa_meth);
199 dest->ecdsa_meth = src->ecdsa_meth;
200 METHOD_ref(dest->ecdsa_meth);
201 }
202 CRYPTO_free_ex_data(&g_ex_data_class, dest, &dest->ex_data);
203 if (!CRYPTO_dup_ex_data(&g_ex_data_class, &dest->ex_data,
204 &src->ex_data)) {
205 return NULL;
206 }
207
208 /* copy the rest */
209 dest->enc_flag = src->enc_flag;
210 dest->conv_form = src->conv_form;
211
212 return dest;
213 }
214
EC_KEY_dup(const EC_KEY * ec_key)215 EC_KEY *EC_KEY_dup(const EC_KEY *ec_key) {
216 EC_KEY *ret = EC_KEY_new();
217 if (ret == NULL) {
218 return NULL;
219 }
220 if (EC_KEY_copy(ret, ec_key) == NULL) {
221 EC_KEY_free(ret);
222 return NULL;
223 }
224 return ret;
225 }
226
EC_KEY_up_ref(EC_KEY * r)227 int EC_KEY_up_ref(EC_KEY *r) {
228 CRYPTO_refcount_inc(&r->references);
229 return 1;
230 }
231
EC_KEY_is_opaque(const EC_KEY * key)232 int EC_KEY_is_opaque(const EC_KEY *key) {
233 return key->ecdsa_meth && (key->ecdsa_meth->flags & ECDSA_FLAG_OPAQUE);
234 }
235
EC_KEY_get0_group(const EC_KEY * key)236 const EC_GROUP *EC_KEY_get0_group(const EC_KEY *key) { return key->group; }
237
EC_KEY_set_group(EC_KEY * key,const EC_GROUP * group)238 int EC_KEY_set_group(EC_KEY *key, const EC_GROUP *group) {
239 EC_GROUP_free(key->group);
240 /* TODO(fork): duplicating the group seems wasteful but see
241 * |EC_KEY_set_conv_form|. */
242 key->group = EC_GROUP_dup(group);
243 if (key->group == NULL) {
244 return 0;
245 }
246 /* XXX: |BN_cmp| is not constant time. */
247 if (key->priv_key != NULL &&
248 BN_cmp(key->priv_key, EC_GROUP_get0_order(group)) >= 0) {
249 return 0;
250 }
251 return 1;
252 }
253
EC_KEY_get0_private_key(const EC_KEY * key)254 const BIGNUM *EC_KEY_get0_private_key(const EC_KEY *key) {
255 return key->priv_key;
256 }
257
EC_KEY_set_private_key(EC_KEY * key,const BIGNUM * priv_key)258 int EC_KEY_set_private_key(EC_KEY *key, const BIGNUM *priv_key) {
259 /* XXX: |BN_cmp| is not constant time. */
260 if (key->group != NULL &&
261 BN_cmp(priv_key, EC_GROUP_get0_order(key->group)) >= 0) {
262 OPENSSL_PUT_ERROR(EC, EC_R_WRONG_ORDER);
263 return 0;
264 }
265 BN_clear_free(key->priv_key);
266 key->priv_key = BN_dup(priv_key);
267 return (key->priv_key == NULL) ? 0 : 1;
268 }
269
EC_KEY_get0_public_key(const EC_KEY * key)270 const EC_POINT *EC_KEY_get0_public_key(const EC_KEY *key) {
271 return key->pub_key;
272 }
273
EC_KEY_set_public_key(EC_KEY * key,const EC_POINT * pub_key)274 int EC_KEY_set_public_key(EC_KEY *key, const EC_POINT *pub_key) {
275 EC_POINT_free(key->pub_key);
276 key->pub_key = EC_POINT_dup(pub_key, key->group);
277 return (key->pub_key == NULL) ? 0 : 1;
278 }
279
EC_KEY_get_enc_flags(const EC_KEY * key)280 unsigned int EC_KEY_get_enc_flags(const EC_KEY *key) { return key->enc_flag; }
281
EC_KEY_set_enc_flags(EC_KEY * key,unsigned int flags)282 void EC_KEY_set_enc_flags(EC_KEY *key, unsigned int flags) {
283 key->enc_flag = flags;
284 }
285
EC_KEY_get_conv_form(const EC_KEY * key)286 point_conversion_form_t EC_KEY_get_conv_form(const EC_KEY *key) {
287 return key->conv_form;
288 }
289
EC_KEY_set_conv_form(EC_KEY * key,point_conversion_form_t cform)290 void EC_KEY_set_conv_form(EC_KEY *key, point_conversion_form_t cform) {
291 key->conv_form = cform;
292 }
293
EC_KEY_check_key(const EC_KEY * eckey)294 int EC_KEY_check_key(const EC_KEY *eckey) {
295 int ok = 0;
296 BN_CTX *ctx = NULL;
297 EC_POINT *point = NULL;
298
299 if (!eckey || !eckey->group || !eckey->pub_key) {
300 OPENSSL_PUT_ERROR(EC, ERR_R_PASSED_NULL_PARAMETER);
301 return 0;
302 }
303
304 if (EC_POINT_is_at_infinity(eckey->group, eckey->pub_key)) {
305 OPENSSL_PUT_ERROR(EC, EC_R_POINT_AT_INFINITY);
306 goto err;
307 }
308
309 ctx = BN_CTX_new();
310
311 if (ctx == NULL) {
312 goto err;
313 }
314
315 /* testing whether the pub_key is on the elliptic curve */
316 if (!EC_POINT_is_on_curve(eckey->group, eckey->pub_key, ctx)) {
317 OPENSSL_PUT_ERROR(EC, EC_R_POINT_IS_NOT_ON_CURVE);
318 goto err;
319 }
320 /* in case the priv_key is present :
321 * check if generator * priv_key == pub_key
322 */
323 if (eckey->priv_key) {
324 /* XXX: |BN_cmp| is not constant time. */
325 if (BN_cmp(eckey->priv_key, EC_GROUP_get0_order(eckey->group)) >= 0) {
326 OPENSSL_PUT_ERROR(EC, EC_R_WRONG_ORDER);
327 goto err;
328 }
329 point = EC_POINT_new(eckey->group);
330 if (point == NULL ||
331 !EC_POINT_mul(eckey->group, point, eckey->priv_key, NULL, NULL, ctx)) {
332 OPENSSL_PUT_ERROR(EC, ERR_R_EC_LIB);
333 goto err;
334 }
335 if (EC_POINT_cmp(eckey->group, point, eckey->pub_key, ctx) != 0) {
336 OPENSSL_PUT_ERROR(EC, EC_R_INVALID_PRIVATE_KEY);
337 goto err;
338 }
339 }
340 ok = 1;
341
342 err:
343 BN_CTX_free(ctx);
344 EC_POINT_free(point);
345 return ok;
346 }
347
EC_KEY_set_public_key_affine_coordinates(EC_KEY * key,BIGNUM * x,BIGNUM * y)348 int EC_KEY_set_public_key_affine_coordinates(EC_KEY *key, BIGNUM *x,
349 BIGNUM *y) {
350 BN_CTX *ctx = NULL;
351 BIGNUM *tx, *ty;
352 EC_POINT *point = NULL;
353 int ok = 0;
354
355 if (!key || !key->group || !x || !y) {
356 OPENSSL_PUT_ERROR(EC, ERR_R_PASSED_NULL_PARAMETER);
357 return 0;
358 }
359 ctx = BN_CTX_new();
360
361 if (ctx == NULL) {
362 return 0;
363 }
364
365 BN_CTX_start(ctx);
366 point = EC_POINT_new(key->group);
367
368 if (point == NULL) {
369 goto err;
370 }
371
372 tx = BN_CTX_get(ctx);
373 ty = BN_CTX_get(ctx);
374 if (tx == NULL ||
375 ty == NULL) {
376 goto err;
377 }
378
379 if (!EC_POINT_set_affine_coordinates_GFp(key->group, point, x, y, ctx) ||
380 !EC_POINT_get_affine_coordinates_GFp(key->group, point, tx, ty, ctx)) {
381 goto err;
382 }
383
384 /* Check if retrieved coordinates match originals: if not values
385 * are out of range. */
386 if (BN_cmp(x, tx) || BN_cmp(y, ty)) {
387 OPENSSL_PUT_ERROR(EC, EC_R_COORDINATES_OUT_OF_RANGE);
388 goto err;
389 }
390
391 if (!EC_KEY_set_public_key(key, point)) {
392 goto err;
393 }
394
395 if (EC_KEY_check_key(key) == 0) {
396 goto err;
397 }
398
399 ok = 1;
400
401 err:
402 BN_CTX_end(ctx);
403 BN_CTX_free(ctx);
404 EC_POINT_free(point);
405 return ok;
406 }
407
EC_KEY_generate_key(EC_KEY * eckey)408 int EC_KEY_generate_key(EC_KEY *eckey) {
409 int ok = 0;
410 BIGNUM *priv_key = NULL;
411 EC_POINT *pub_key = NULL;
412
413 if (!eckey || !eckey->group) {
414 OPENSSL_PUT_ERROR(EC, ERR_R_PASSED_NULL_PARAMETER);
415 return 0;
416 }
417
418 if (eckey->priv_key == NULL) {
419 priv_key = BN_new();
420 if (priv_key == NULL) {
421 goto err;
422 }
423 } else {
424 priv_key = eckey->priv_key;
425 }
426
427 const BIGNUM *order = EC_GROUP_get0_order(eckey->group);
428 if (!BN_rand_range_ex(priv_key, 1, order)) {
429 goto err;
430 }
431
432 if (eckey->pub_key == NULL) {
433 pub_key = EC_POINT_new(eckey->group);
434 if (pub_key == NULL) {
435 goto err;
436 }
437 } else {
438 pub_key = eckey->pub_key;
439 }
440
441 if (!EC_POINT_mul(eckey->group, pub_key, priv_key, NULL, NULL, NULL)) {
442 goto err;
443 }
444
445 eckey->priv_key = priv_key;
446 eckey->pub_key = pub_key;
447
448 ok = 1;
449
450 err:
451 if (eckey->pub_key == NULL) {
452 EC_POINT_free(pub_key);
453 }
454 if (eckey->priv_key == NULL) {
455 BN_free(priv_key);
456 }
457 return ok;
458 }
459
EC_KEY_get_ex_new_index(long argl,void * argp,CRYPTO_EX_unused * unused,CRYPTO_EX_dup * dup_func,CRYPTO_EX_free * free_func)460 int EC_KEY_get_ex_new_index(long argl, void *argp, CRYPTO_EX_unused *unused,
461 CRYPTO_EX_dup *dup_func,
462 CRYPTO_EX_free *free_func) {
463 int index;
464 if (!CRYPTO_get_ex_new_index(&g_ex_data_class, &index, argl, argp, dup_func,
465 free_func)) {
466 return -1;
467 }
468 return index;
469 }
470
EC_KEY_set_ex_data(EC_KEY * d,int idx,void * arg)471 int EC_KEY_set_ex_data(EC_KEY *d, int idx, void *arg) {
472 return CRYPTO_set_ex_data(&d->ex_data, idx, arg);
473 }
474
EC_KEY_get_ex_data(const EC_KEY * d,int idx)475 void *EC_KEY_get_ex_data(const EC_KEY *d, int idx) {
476 return CRYPTO_get_ex_data(&d->ex_data, idx);
477 }
478
EC_KEY_set_asn1_flag(EC_KEY * key,int flag)479 void EC_KEY_set_asn1_flag(EC_KEY *key, int flag) {}
480