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/ecdsa.h>
74 #include <openssl/engine.h>
75 #include <openssl/err.h>
76 #include <openssl/ex_data.h>
77 #include <openssl/mem.h>
78 #include <openssl/thread.h>
79
80 #include "internal.h"
81 #include "../delocate.h"
82 #include "../../internal.h"
83
84
85 DEFINE_STATIC_EX_DATA_CLASS(g_ec_ex_data_class);
86
EC_KEY_new(void)87 EC_KEY *EC_KEY_new(void) { return EC_KEY_new_method(NULL); }
88
EC_KEY_new_method(const ENGINE * engine)89 EC_KEY *EC_KEY_new_method(const ENGINE *engine) {
90 EC_KEY *ret = OPENSSL_malloc(sizeof(EC_KEY));
91 if (ret == NULL) {
92 OPENSSL_PUT_ERROR(EC, ERR_R_MALLOC_FAILURE);
93 return NULL;
94 }
95
96 OPENSSL_memset(ret, 0, sizeof(EC_KEY));
97
98 if (engine) {
99 ret->ecdsa_meth = ENGINE_get_ECDSA_method(engine);
100 }
101 if (ret->ecdsa_meth) {
102 METHOD_ref(ret->ecdsa_meth);
103 }
104
105 ret->conv_form = POINT_CONVERSION_UNCOMPRESSED;
106 ret->references = 1;
107
108 CRYPTO_new_ex_data(&ret->ex_data);
109
110 if (ret->ecdsa_meth && ret->ecdsa_meth->init && !ret->ecdsa_meth->init(ret)) {
111 CRYPTO_free_ex_data(g_ec_ex_data_class_bss_get(), ret, &ret->ex_data);
112 if (ret->ecdsa_meth) {
113 METHOD_unref(ret->ecdsa_meth);
114 }
115 OPENSSL_free(ret);
116 return NULL;
117 }
118
119 return ret;
120 }
121
EC_KEY_new_by_curve_name(int nid)122 EC_KEY *EC_KEY_new_by_curve_name(int nid) {
123 EC_KEY *ret = EC_KEY_new();
124 if (ret == NULL) {
125 OPENSSL_PUT_ERROR(EC, ERR_R_MALLOC_FAILURE);
126 return NULL;
127 }
128 ret->group = EC_GROUP_new_by_curve_name(nid);
129 if (ret->group == NULL) {
130 EC_KEY_free(ret);
131 return NULL;
132 }
133 return ret;
134 }
135
EC_KEY_free(EC_KEY * r)136 void EC_KEY_free(EC_KEY *r) {
137 if (r == NULL) {
138 return;
139 }
140
141 if (!CRYPTO_refcount_dec_and_test_zero(&r->references)) {
142 return;
143 }
144
145 if (r->ecdsa_meth) {
146 if (r->ecdsa_meth->finish) {
147 r->ecdsa_meth->finish(r);
148 }
149 METHOD_unref(r->ecdsa_meth);
150 }
151
152 EC_GROUP_free(r->group);
153 EC_POINT_free(r->pub_key);
154 BN_clear_free(r->priv_key);
155 BN_free(r->fixed_k);
156
157 CRYPTO_free_ex_data(g_ec_ex_data_class_bss_get(), r, &r->ex_data);
158
159 OPENSSL_cleanse((void *)r, sizeof(EC_KEY));
160 OPENSSL_free(r);
161 }
162
EC_KEY_copy(EC_KEY * dest,const EC_KEY * src)163 EC_KEY *EC_KEY_copy(EC_KEY *dest, const EC_KEY *src) {
164 if (dest == NULL || src == NULL) {
165 OPENSSL_PUT_ERROR(EC, ERR_R_PASSED_NULL_PARAMETER);
166 return NULL;
167 }
168 /* Copy the parameters. */
169 if (src->group) {
170 /* TODO(fork): duplicating the group seems wasteful. */
171 EC_GROUP_free(dest->group);
172 dest->group = EC_GROUP_dup(src->group);
173 if (dest->group == NULL) {
174 return NULL;
175 }
176 }
177
178 /* Copy the public key. */
179 if (src->pub_key && src->group) {
180 EC_POINT_free(dest->pub_key);
181 dest->pub_key = EC_POINT_dup(src->pub_key, src->group);
182 if (dest->pub_key == NULL) {
183 return NULL;
184 }
185 }
186
187 /* copy the private key */
188 if (src->priv_key) {
189 if (dest->priv_key == NULL) {
190 dest->priv_key = BN_new();
191 if (dest->priv_key == NULL) {
192 return NULL;
193 }
194 }
195 if (!BN_copy(dest->priv_key, src->priv_key)) {
196 return NULL;
197 }
198 }
199 /* copy method/extra data */
200 if (src->ecdsa_meth) {
201 METHOD_unref(dest->ecdsa_meth);
202 dest->ecdsa_meth = src->ecdsa_meth;
203 METHOD_ref(dest->ecdsa_meth);
204 }
205
206 /* copy the rest */
207 dest->enc_flag = src->enc_flag;
208 dest->conv_form = src->conv_form;
209
210 return dest;
211 }
212
EC_KEY_dup(const EC_KEY * ec_key)213 EC_KEY *EC_KEY_dup(const EC_KEY *ec_key) {
214 EC_KEY *ret = EC_KEY_new();
215 if (ret == NULL) {
216 return NULL;
217 }
218 if (EC_KEY_copy(ret, ec_key) == NULL) {
219 EC_KEY_free(ret);
220 return NULL;
221 }
222 return ret;
223 }
224
EC_KEY_up_ref(EC_KEY * r)225 int EC_KEY_up_ref(EC_KEY *r) {
226 CRYPTO_refcount_inc(&r->references);
227 return 1;
228 }
229
EC_KEY_is_opaque(const EC_KEY * key)230 int EC_KEY_is_opaque(const EC_KEY *key) {
231 return key->ecdsa_meth && (key->ecdsa_meth->flags & ECDSA_FLAG_OPAQUE);
232 }
233
EC_KEY_get0_group(const EC_KEY * key)234 const EC_GROUP *EC_KEY_get0_group(const EC_KEY *key) { return key->group; }
235
EC_KEY_set_group(EC_KEY * key,const EC_GROUP * group)236 int EC_KEY_set_group(EC_KEY *key, const EC_GROUP *group) {
237 EC_GROUP_free(key->group);
238 /* TODO(fork): duplicating the group seems wasteful but see
239 * |EC_KEY_set_conv_form|. */
240 key->group = EC_GROUP_dup(group);
241 if (key->group == NULL) {
242 return 0;
243 }
244 /* XXX: |BN_cmp| is not constant time. */
245 if (key->priv_key != NULL &&
246 BN_cmp(key->priv_key, EC_GROUP_get0_order(group)) >= 0) {
247 return 0;
248 }
249 return 1;
250 }
251
EC_KEY_get0_private_key(const EC_KEY * key)252 const BIGNUM *EC_KEY_get0_private_key(const EC_KEY *key) {
253 return key->priv_key;
254 }
255
EC_KEY_set_private_key(EC_KEY * key,const BIGNUM * priv_key)256 int EC_KEY_set_private_key(EC_KEY *key, const BIGNUM *priv_key) {
257 /* XXX: |BN_cmp| is not constant time. */
258 if (key->group != NULL &&
259 BN_cmp(priv_key, EC_GROUP_get0_order(key->group)) >= 0) {
260 OPENSSL_PUT_ERROR(EC, EC_R_WRONG_ORDER);
261 return 0;
262 }
263 BN_clear_free(key->priv_key);
264 key->priv_key = BN_dup(priv_key);
265 return (key->priv_key == NULL) ? 0 : 1;
266 }
267
EC_KEY_get0_public_key(const EC_KEY * key)268 const EC_POINT *EC_KEY_get0_public_key(const EC_KEY *key) {
269 return key->pub_key;
270 }
271
EC_KEY_set_public_key(EC_KEY * key,const EC_POINT * pub_key)272 int EC_KEY_set_public_key(EC_KEY *key, const EC_POINT *pub_key) {
273 EC_POINT_free(key->pub_key);
274 key->pub_key = EC_POINT_dup(pub_key, key->group);
275 return (key->pub_key == NULL) ? 0 : 1;
276 }
277
EC_KEY_get_enc_flags(const EC_KEY * key)278 unsigned int EC_KEY_get_enc_flags(const EC_KEY *key) { return key->enc_flag; }
279
EC_KEY_set_enc_flags(EC_KEY * key,unsigned int flags)280 void EC_KEY_set_enc_flags(EC_KEY *key, unsigned int flags) {
281 key->enc_flag = flags;
282 }
283
EC_KEY_get_conv_form(const EC_KEY * key)284 point_conversion_form_t EC_KEY_get_conv_form(const EC_KEY *key) {
285 return key->conv_form;
286 }
287
EC_KEY_set_conv_form(EC_KEY * key,point_conversion_form_t cform)288 void EC_KEY_set_conv_form(EC_KEY *key, point_conversion_form_t cform) {
289 key->conv_form = cform;
290 }
291
EC_KEY_check_key(const EC_KEY * eckey)292 int EC_KEY_check_key(const EC_KEY *eckey) {
293 int ok = 0;
294 BN_CTX *ctx = NULL;
295 EC_POINT *point = NULL;
296
297 if (!eckey || !eckey->group || !eckey->pub_key) {
298 OPENSSL_PUT_ERROR(EC, ERR_R_PASSED_NULL_PARAMETER);
299 return 0;
300 }
301
302 if (EC_POINT_is_at_infinity(eckey->group, eckey->pub_key)) {
303 OPENSSL_PUT_ERROR(EC, EC_R_POINT_AT_INFINITY);
304 goto err;
305 }
306
307 ctx = BN_CTX_new();
308
309 if (ctx == NULL) {
310 goto err;
311 }
312
313 /* testing whether the pub_key is on the elliptic curve */
314 if (!EC_POINT_is_on_curve(eckey->group, eckey->pub_key, ctx)) {
315 OPENSSL_PUT_ERROR(EC, EC_R_POINT_IS_NOT_ON_CURVE);
316 goto err;
317 }
318 /* in case the priv_key is present :
319 * check if generator * priv_key == pub_key
320 */
321 if (eckey->priv_key) {
322 /* XXX: |BN_cmp| is not constant time. */
323 if (BN_cmp(eckey->priv_key, EC_GROUP_get0_order(eckey->group)) >= 0) {
324 OPENSSL_PUT_ERROR(EC, EC_R_WRONG_ORDER);
325 goto err;
326 }
327 point = EC_POINT_new(eckey->group);
328 if (point == NULL ||
329 !EC_POINT_mul(eckey->group, point, eckey->priv_key, NULL, NULL, ctx)) {
330 OPENSSL_PUT_ERROR(EC, ERR_R_EC_LIB);
331 goto err;
332 }
333 if (EC_POINT_cmp(eckey->group, point, eckey->pub_key, ctx) != 0) {
334 OPENSSL_PUT_ERROR(EC, EC_R_INVALID_PRIVATE_KEY);
335 goto err;
336 }
337 }
338 ok = 1;
339
340 err:
341 BN_CTX_free(ctx);
342 EC_POINT_free(point);
343 return ok;
344 }
345
EC_KEY_check_fips(const EC_KEY * key)346 int EC_KEY_check_fips(const EC_KEY *key) {
347 if (EC_KEY_is_opaque(key)) {
348 /* Opaque keys can't be checked. */
349 OPENSSL_PUT_ERROR(EC, EC_R_PUBLIC_KEY_VALIDATION_FAILED);
350 return 0;
351 }
352
353 if (!EC_KEY_check_key(key)) {
354 return 0;
355 }
356
357 if (key->priv_key) {
358 uint8_t data[16] = {0};
359 ECDSA_SIG *sig = ECDSA_do_sign(data, sizeof(data), key);
360 #if defined(BORINGSSL_FIPS_BREAK_ECDSA_PWCT)
361 data[0] = ~data[0];
362 #endif
363 int ok = sig != NULL &&
364 ECDSA_do_verify(data, sizeof(data), sig, key);
365 ECDSA_SIG_free(sig);
366 if (!ok) {
367 OPENSSL_PUT_ERROR(EC, EC_R_PUBLIC_KEY_VALIDATION_FAILED);
368 return 0;
369 }
370 }
371
372 return 1;
373 }
374
EC_KEY_set_public_key_affine_coordinates(EC_KEY * key,BIGNUM * x,BIGNUM * y)375 int EC_KEY_set_public_key_affine_coordinates(EC_KEY *key, BIGNUM *x,
376 BIGNUM *y) {
377 BN_CTX *ctx = NULL;
378 BIGNUM *tx, *ty;
379 EC_POINT *point = NULL;
380 int ok = 0;
381
382 if (!key || !key->group || !x || !y) {
383 OPENSSL_PUT_ERROR(EC, ERR_R_PASSED_NULL_PARAMETER);
384 return 0;
385 }
386 ctx = BN_CTX_new();
387
388 if (ctx == NULL) {
389 return 0;
390 }
391
392 BN_CTX_start(ctx);
393 point = EC_POINT_new(key->group);
394
395 if (point == NULL) {
396 goto err;
397 }
398
399 tx = BN_CTX_get(ctx);
400 ty = BN_CTX_get(ctx);
401 if (tx == NULL ||
402 ty == NULL) {
403 goto err;
404 }
405
406 if (!EC_POINT_set_affine_coordinates_GFp(key->group, point, x, y, ctx) ||
407 !EC_POINT_get_affine_coordinates_GFp(key->group, point, tx, ty, ctx)) {
408 goto err;
409 }
410
411 /* Check if retrieved coordinates match originals: if not values
412 * are out of range. */
413 if (BN_cmp(x, tx) || BN_cmp(y, ty)) {
414 OPENSSL_PUT_ERROR(EC, EC_R_COORDINATES_OUT_OF_RANGE);
415 goto err;
416 }
417
418 if (!EC_KEY_set_public_key(key, point)) {
419 goto err;
420 }
421
422 if (EC_KEY_check_key(key) == 0) {
423 goto err;
424 }
425
426 ok = 1;
427
428 err:
429 BN_CTX_end(ctx);
430 BN_CTX_free(ctx);
431 EC_POINT_free(point);
432 return ok;
433 }
434
EC_KEY_generate_key(EC_KEY * eckey)435 int EC_KEY_generate_key(EC_KEY *eckey) {
436 int ok = 0;
437 BIGNUM *priv_key = NULL;
438 EC_POINT *pub_key = NULL;
439
440 if (!eckey || !eckey->group) {
441 OPENSSL_PUT_ERROR(EC, ERR_R_PASSED_NULL_PARAMETER);
442 return 0;
443 }
444
445 if (eckey->priv_key == NULL) {
446 priv_key = BN_new();
447 if (priv_key == NULL) {
448 goto err;
449 }
450 } else {
451 priv_key = eckey->priv_key;
452 }
453
454 const BIGNUM *order = EC_GROUP_get0_order(eckey->group);
455
456 /* Check that the size of the group order is FIPS compliant (FIPS 186-4
457 * B.4.2). */
458 if (BN_num_bits(order) < 160) {
459 OPENSSL_PUT_ERROR(EC, EC_R_INVALID_GROUP_ORDER);
460 goto err;
461 }
462
463 /* Generate the private key by testing candidates (FIPS 186-4 B.4.2). */
464 if (!BN_rand_range_ex(priv_key, 1, order)) {
465 goto err;
466 }
467
468 if (eckey->pub_key == NULL) {
469 pub_key = EC_POINT_new(eckey->group);
470 if (pub_key == NULL) {
471 goto err;
472 }
473 } else {
474 pub_key = eckey->pub_key;
475 }
476
477 if (!EC_POINT_mul(eckey->group, pub_key, priv_key, NULL, NULL, NULL)) {
478 goto err;
479 }
480
481 eckey->priv_key = priv_key;
482 eckey->pub_key = pub_key;
483
484 ok = 1;
485
486 err:
487 if (eckey->pub_key == NULL) {
488 EC_POINT_free(pub_key);
489 }
490 if (eckey->priv_key == NULL) {
491 BN_free(priv_key);
492 }
493 return ok;
494 }
495
EC_KEY_generate_key_fips(EC_KEY * eckey)496 int EC_KEY_generate_key_fips(EC_KEY *eckey) {
497 return EC_KEY_generate_key(eckey) && EC_KEY_check_fips(eckey);
498 }
499
EC_KEY_get_ex_new_index(long argl,void * argp,CRYPTO_EX_unused * unused,CRYPTO_EX_dup * dup_unused,CRYPTO_EX_free * free_func)500 int EC_KEY_get_ex_new_index(long argl, void *argp, CRYPTO_EX_unused *unused,
501 CRYPTO_EX_dup *dup_unused,
502 CRYPTO_EX_free *free_func) {
503 int index;
504 if (!CRYPTO_get_ex_new_index(g_ec_ex_data_class_bss_get(), &index, argl, argp,
505 free_func)) {
506 return -1;
507 }
508 return index;
509 }
510
EC_KEY_set_ex_data(EC_KEY * d,int idx,void * arg)511 int EC_KEY_set_ex_data(EC_KEY *d, int idx, void *arg) {
512 return CRYPTO_set_ex_data(&d->ex_data, idx, arg);
513 }
514
EC_KEY_get_ex_data(const EC_KEY * d,int idx)515 void *EC_KEY_get_ex_data(const EC_KEY *d, int idx) {
516 return CRYPTO_get_ex_data(&d->ex_data, idx);
517 }
518
EC_KEY_set_asn1_flag(EC_KEY * key,int flag)519 void EC_KEY_set_asn1_flag(EC_KEY *key, int flag) {}
520