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 = (EC_KEY *)OPENSSL_malloc(sizeof(EC_KEY));
89 if (ret == NULL) {
90 OPENSSL_PUT_ERROR(EC, ERR_R_MALLOC_FAILURE);
91 return NULL;
92 }
93
94 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->version = 1;
104 ret->conv_form = POINT_CONVERSION_UNCOMPRESSED;
105 ret->references = 1;
106
107 CRYPTO_new_ex_data(&ret->ex_data);
108
109 if (ret->ecdsa_meth && ret->ecdsa_meth->init && !ret->ecdsa_meth->init(ret)) {
110 CRYPTO_free_ex_data(&g_ex_data_class, ret, &ret->ex_data);
111 if (ret->ecdsa_meth) {
112 METHOD_unref(ret->ecdsa_meth);
113 }
114 OPENSSL_free(ret);
115 return NULL;
116 }
117
118 return ret;
119 }
120
EC_KEY_new_by_curve_name(int nid)121 EC_KEY *EC_KEY_new_by_curve_name(int nid) {
122 EC_KEY *ret = EC_KEY_new();
123 if (ret == NULL) {
124 OPENSSL_PUT_ERROR(EC, ERR_R_MALLOC_FAILURE);
125 return NULL;
126 }
127 ret->group = EC_GROUP_new_by_curve_name(nid);
128 if (ret->group == NULL) {
129 EC_KEY_free(ret);
130 return NULL;
131 }
132 return ret;
133 }
134
EC_KEY_free(EC_KEY * r)135 void EC_KEY_free(EC_KEY *r) {
136 if (r == NULL) {
137 return;
138 }
139
140 if (!CRYPTO_refcount_dec_and_test_zero(&r->references)) {
141 return;
142 }
143
144 if (r->ecdsa_meth) {
145 if (r->ecdsa_meth->finish) {
146 r->ecdsa_meth->finish(r);
147 }
148 METHOD_unref(r->ecdsa_meth);
149 }
150
151 EC_GROUP_free(r->group);
152 EC_POINT_free(r->pub_key);
153 BN_clear_free(r->priv_key);
154
155 CRYPTO_free_ex_data(&g_ex_data_class, r, &r->ex_data);
156
157 OPENSSL_cleanse((void *)r, sizeof(EC_KEY));
158 OPENSSL_free(r);
159 }
160
EC_KEY_copy(EC_KEY * dest,const EC_KEY * src)161 EC_KEY *EC_KEY_copy(EC_KEY *dest, const EC_KEY *src) {
162 if (dest == NULL || src == NULL) {
163 OPENSSL_PUT_ERROR(EC, ERR_R_PASSED_NULL_PARAMETER);
164 return NULL;
165 }
166 /* Copy the parameters. */
167 if (src->group) {
168 /* TODO(fork): duplicating the group seems wasteful. */
169 EC_GROUP_free(dest->group);
170 dest->group = EC_GROUP_dup(src->group);
171 if (dest->group == NULL) {
172 return NULL;
173 }
174 }
175
176 /* Copy the public key. */
177 if (src->pub_key && src->group) {
178 EC_POINT_free(dest->pub_key);
179 dest->pub_key = EC_POINT_dup(src->pub_key, src->group);
180 if (dest->pub_key == NULL) {
181 return NULL;
182 }
183 }
184
185 /* copy the private key */
186 if (src->priv_key) {
187 if (dest->priv_key == NULL) {
188 dest->priv_key = BN_new();
189 if (dest->priv_key == NULL) {
190 return NULL;
191 }
192 }
193 if (!BN_copy(dest->priv_key, src->priv_key)) {
194 return NULL;
195 }
196 }
197 /* copy method/extra data */
198 if (src->ecdsa_meth) {
199 METHOD_unref(dest->ecdsa_meth);
200 dest->ecdsa_meth = src->ecdsa_meth;
201 METHOD_ref(dest->ecdsa_meth);
202 }
203 CRYPTO_free_ex_data(&g_ex_data_class, dest, &dest->ex_data);
204 if (!CRYPTO_dup_ex_data(&g_ex_data_class, &dest->ex_data,
205 &src->ex_data)) {
206 return NULL;
207 }
208
209 /* copy the rest */
210 dest->enc_flag = src->enc_flag;
211 dest->conv_form = src->conv_form;
212 dest->version = src->version;
213 dest->flags = src->flags;
214
215 return dest;
216 }
217
EC_KEY_dup(const EC_KEY * ec_key)218 EC_KEY *EC_KEY_dup(const EC_KEY *ec_key) {
219 EC_KEY *ret = EC_KEY_new();
220 if (ret == NULL) {
221 return NULL;
222 }
223 if (EC_KEY_copy(ret, ec_key) == NULL) {
224 EC_KEY_free(ret);
225 return NULL;
226 }
227 return ret;
228 }
229
EC_KEY_up_ref(EC_KEY * r)230 int EC_KEY_up_ref(EC_KEY *r) {
231 CRYPTO_refcount_inc(&r->references);
232 return 1;
233 }
234
EC_KEY_is_opaque(const EC_KEY * key)235 int EC_KEY_is_opaque(const EC_KEY *key) {
236 return key->ecdsa_meth && (key->ecdsa_meth->flags & ECDSA_FLAG_OPAQUE);
237 }
238
EC_KEY_get0_group(const EC_KEY * key)239 const EC_GROUP *EC_KEY_get0_group(const EC_KEY *key) { return key->group; }
240
EC_KEY_set_group(EC_KEY * key,const EC_GROUP * group)241 int EC_KEY_set_group(EC_KEY *key, const EC_GROUP *group) {
242 EC_GROUP_free(key->group);
243 /* TODO(fork): duplicating the group seems wasteful but see
244 * |EC_KEY_set_conv_form|. */
245 key->group = EC_GROUP_dup(group);
246 if (key->group == NULL) {
247 return 0;
248 }
249 /* XXX: |BN_cmp| is not constant time. */
250 if (key->priv_key != NULL &&
251 BN_cmp(key->priv_key, EC_GROUP_get0_order(group)) >= 0) {
252 return 0;
253 }
254 return 1;
255 }
256
EC_KEY_get0_private_key(const EC_KEY * key)257 const BIGNUM *EC_KEY_get0_private_key(const EC_KEY *key) {
258 return key->priv_key;
259 }
260
EC_KEY_set_private_key(EC_KEY * key,const BIGNUM * priv_key)261 int EC_KEY_set_private_key(EC_KEY *key, const BIGNUM *priv_key) {
262 /* XXX: |BN_cmp| is not constant time. */
263 if (key->group != NULL &&
264 BN_cmp(priv_key, EC_GROUP_get0_order(key->group)) >= 0) {
265 OPENSSL_PUT_ERROR(EC, EC_R_WRONG_ORDER);
266 return 0;
267 }
268 BN_clear_free(key->priv_key);
269 key->priv_key = BN_dup(priv_key);
270 return (key->priv_key == NULL) ? 0 : 1;
271 }
272
EC_KEY_get0_public_key(const EC_KEY * key)273 const EC_POINT *EC_KEY_get0_public_key(const EC_KEY *key) {
274 return key->pub_key;
275 }
276
EC_KEY_set_public_key(EC_KEY * key,const EC_POINT * pub_key)277 int EC_KEY_set_public_key(EC_KEY *key, const EC_POINT *pub_key) {
278 EC_POINT_free(key->pub_key);
279 key->pub_key = EC_POINT_dup(pub_key, key->group);
280 return (key->pub_key == NULL) ? 0 : 1;
281 }
282
EC_KEY_get_enc_flags(const EC_KEY * key)283 unsigned int EC_KEY_get_enc_flags(const EC_KEY *key) { return key->enc_flag; }
284
EC_KEY_set_enc_flags(EC_KEY * key,unsigned int flags)285 void EC_KEY_set_enc_flags(EC_KEY *key, unsigned int flags) {
286 key->enc_flag = flags;
287 }
288
EC_KEY_get_conv_form(const EC_KEY * key)289 point_conversion_form_t EC_KEY_get_conv_form(const EC_KEY *key) {
290 return key->conv_form;
291 }
292
EC_KEY_set_conv_form(EC_KEY * key,point_conversion_form_t cform)293 void EC_KEY_set_conv_form(EC_KEY *key, point_conversion_form_t cform) {
294 key->conv_form = cform;
295 }
296
EC_KEY_check_key(const EC_KEY * eckey)297 int EC_KEY_check_key(const EC_KEY *eckey) {
298 int ok = 0;
299 BN_CTX *ctx = NULL;
300 EC_POINT *point = NULL;
301
302 if (!eckey || !eckey->group || !eckey->pub_key) {
303 OPENSSL_PUT_ERROR(EC, ERR_R_PASSED_NULL_PARAMETER);
304 return 0;
305 }
306
307 if (EC_POINT_is_at_infinity(eckey->group, eckey->pub_key)) {
308 OPENSSL_PUT_ERROR(EC, EC_R_POINT_AT_INFINITY);
309 goto err;
310 }
311
312 ctx = BN_CTX_new();
313
314 if (ctx == NULL) {
315 goto err;
316 }
317
318 /* testing whether the pub_key is on the elliptic curve */
319 if (!EC_POINT_is_on_curve(eckey->group, eckey->pub_key, ctx)) {
320 OPENSSL_PUT_ERROR(EC, EC_R_POINT_IS_NOT_ON_CURVE);
321 goto err;
322 }
323 /* TODO(fork): can this be skipped if the cofactor is one or if we're about
324 * to check the private key, below? */
325 if (eckey->group->meth->check_pub_key_order != NULL &&
326 !eckey->group->meth->check_pub_key_order(eckey->group, eckey->pub_key,
327 ctx)) {
328 OPENSSL_PUT_ERROR(EC, EC_R_WRONG_ORDER);
329 goto err;
330 }
331 /* in case the priv_key is present :
332 * check if generator * priv_key == pub_key
333 */
334 if (eckey->priv_key) {
335 /* XXX: |BN_cmp| is not constant time. */
336 if (BN_cmp(eckey->priv_key, EC_GROUP_get0_order(eckey->group)) >= 0) {
337 OPENSSL_PUT_ERROR(EC, EC_R_WRONG_ORDER);
338 goto err;
339 }
340 point = EC_POINT_new(eckey->group);
341 if (point == NULL ||
342 !EC_POINT_mul(eckey->group, point, eckey->priv_key, NULL, NULL, ctx)) {
343 OPENSSL_PUT_ERROR(EC, ERR_R_EC_LIB);
344 goto err;
345 }
346 if (EC_POINT_cmp(eckey->group, point, eckey->pub_key, ctx) != 0) {
347 OPENSSL_PUT_ERROR(EC, EC_R_INVALID_PRIVATE_KEY);
348 goto err;
349 }
350 }
351 ok = 1;
352
353 err:
354 BN_CTX_free(ctx);
355 EC_POINT_free(point);
356 return ok;
357 }
358
EC_KEY_set_public_key_affine_coordinates(EC_KEY * key,BIGNUM * x,BIGNUM * y)359 int EC_KEY_set_public_key_affine_coordinates(EC_KEY *key, BIGNUM *x,
360 BIGNUM *y) {
361 BN_CTX *ctx = NULL;
362 BIGNUM *tx, *ty;
363 EC_POINT *point = NULL;
364 int ok = 0;
365
366 if (!key || !key->group || !x || !y) {
367 OPENSSL_PUT_ERROR(EC, ERR_R_PASSED_NULL_PARAMETER);
368 return 0;
369 }
370 ctx = BN_CTX_new();
371 point = EC_POINT_new(key->group);
372
373 if (ctx == NULL ||
374 point == NULL) {
375 goto err;
376 }
377
378 tx = BN_CTX_get(ctx);
379 ty = BN_CTX_get(ctx);
380
381 if (!EC_POINT_set_affine_coordinates_GFp(key->group, point, x, y, ctx) ||
382 !EC_POINT_get_affine_coordinates_GFp(key->group, point, tx, ty, ctx)) {
383 goto err;
384 }
385
386 /* Check if retrieved coordinates match originals: if not values
387 * are out of range. */
388 if (BN_cmp(x, tx) || BN_cmp(y, ty)) {
389 OPENSSL_PUT_ERROR(EC, EC_R_COORDINATES_OUT_OF_RANGE);
390 goto err;
391 }
392
393 if (!EC_KEY_set_public_key(key, point)) {
394 goto err;
395 }
396
397 if (EC_KEY_check_key(key) == 0) {
398 goto err;
399 }
400
401 ok = 1;
402
403 err:
404 BN_CTX_free(ctx);
405 EC_POINT_free(point);
406 return ok;
407 }
408
EC_KEY_generate_key(EC_KEY * eckey)409 int EC_KEY_generate_key(EC_KEY *eckey) {
410 int ok = 0;
411 BIGNUM *priv_key = NULL;
412 EC_POINT *pub_key = NULL;
413
414 if (!eckey || !eckey->group) {
415 OPENSSL_PUT_ERROR(EC, ERR_R_PASSED_NULL_PARAMETER);
416 return 0;
417 }
418
419 if (eckey->priv_key == NULL) {
420 priv_key = BN_new();
421 if (priv_key == NULL) {
422 goto err;
423 }
424 } else {
425 priv_key = eckey->priv_key;
426 }
427
428 const BIGNUM *order = EC_GROUP_get0_order(eckey->group);
429 do {
430 if (!BN_rand_range(priv_key, order)) {
431 goto err;
432 }
433 } while (BN_is_zero(priv_key));
434
435 if (eckey->pub_key == NULL) {
436 pub_key = EC_POINT_new(eckey->group);
437 if (pub_key == NULL) {
438 goto err;
439 }
440 } else {
441 pub_key = eckey->pub_key;
442 }
443
444 if (!EC_POINT_mul(eckey->group, pub_key, priv_key, NULL, NULL, NULL)) {
445 goto err;
446 }
447
448 eckey->priv_key = priv_key;
449 eckey->pub_key = pub_key;
450
451 ok = 1;
452
453 err:
454 if (eckey->pub_key == NULL) {
455 EC_POINT_free(pub_key);
456 }
457 if (eckey->priv_key == NULL) {
458 BN_free(priv_key);
459 }
460 return ok;
461 }
462
EC_KEY_get_ex_new_index(long argl,void * argp,CRYPTO_EX_unused * unused,CRYPTO_EX_dup * dup_func,CRYPTO_EX_free * free_func)463 int EC_KEY_get_ex_new_index(long argl, void *argp, CRYPTO_EX_unused *unused,
464 CRYPTO_EX_dup *dup_func,
465 CRYPTO_EX_free *free_func) {
466 int index;
467 if (!CRYPTO_get_ex_new_index(&g_ex_data_class, &index, argl, argp, dup_func,
468 free_func)) {
469 return -1;
470 }
471 return index;
472 }
473
EC_KEY_set_ex_data(EC_KEY * d,int idx,void * arg)474 int EC_KEY_set_ex_data(EC_KEY *d, int idx, void *arg) {
475 return CRYPTO_set_ex_data(&d->ex_data, idx, arg);
476 }
477
EC_KEY_get_ex_data(const EC_KEY * d,int idx)478 void *EC_KEY_get_ex_data(const EC_KEY *d, int idx) {
479 return CRYPTO_get_ex_data(&d->ex_data, idx);
480 }
481
EC_KEY_set_asn1_flag(EC_KEY * key,int flag)482 void EC_KEY_set_asn1_flag(EC_KEY *key, int flag) {}
483