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, EC_KEY_new_method, 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 if (!CRYPTO_new_ex_data(&g_ex_data_class, ret, &ret->ex_data)) {
108 goto err1;
109 }
110
111 if (ret->ecdsa_meth && ret->ecdsa_meth->init && !ret->ecdsa_meth->init(ret)) {
112 goto err2;
113 }
114
115 return ret;
116
117 err2:
118 CRYPTO_free_ex_data(&g_ex_data_class, ret, &ret->ex_data);
119 err1:
120 if (ret->ecdsa_meth) {
121 METHOD_unref(ret->ecdsa_meth);
122 }
123 OPENSSL_free(ret);
124 return NULL;
125 }
126
EC_KEY_new_by_curve_name(int nid)127 EC_KEY *EC_KEY_new_by_curve_name(int nid) {
128 EC_KEY *ret = EC_KEY_new();
129 if (ret == NULL) {
130 OPENSSL_PUT_ERROR(EC, EC_KEY_new_by_curve_name, ERR_R_MALLOC_FAILURE);
131 return NULL;
132 }
133 ret->group = EC_GROUP_new_by_curve_name(nid);
134 if (ret->group == NULL) {
135 EC_KEY_free(ret);
136 return NULL;
137 }
138 return ret;
139 }
140
EC_KEY_free(EC_KEY * r)141 void EC_KEY_free(EC_KEY *r) {
142 if (r == NULL) {
143 return;
144 }
145
146 if (!CRYPTO_refcount_dec_and_test_zero(&r->references)) {
147 return;
148 }
149
150 if (r->ecdsa_meth) {
151 if (r->ecdsa_meth->finish) {
152 r->ecdsa_meth->finish(r);
153 }
154 METHOD_unref(r->ecdsa_meth);
155 }
156
157 EC_GROUP_free(r->group);
158 EC_POINT_free(r->pub_key);
159 BN_clear_free(r->priv_key);
160
161 CRYPTO_free_ex_data(&g_ex_data_class, r, &r->ex_data);
162
163 OPENSSL_cleanse((void *)r, sizeof(EC_KEY));
164 OPENSSL_free(r);
165 }
166
EC_KEY_copy(EC_KEY * dest,const EC_KEY * src)167 EC_KEY *EC_KEY_copy(EC_KEY *dest, const EC_KEY *src) {
168 if (dest == NULL || src == NULL) {
169 OPENSSL_PUT_ERROR(EC, EC_KEY_copy, ERR_R_PASSED_NULL_PARAMETER);
170 return NULL;
171 }
172 /* Copy the parameters. */
173 if (src->group) {
174 /* TODO(fork): duplicating the group seems wasteful. */
175 EC_GROUP_free(dest->group);
176 dest->group = EC_GROUP_dup(src->group);
177 if (dest->group == NULL) {
178 return NULL;
179 }
180 }
181
182 /* Copy the public key. */
183 if (src->pub_key && src->group) {
184 EC_POINT_free(dest->pub_key);
185 dest->pub_key = EC_POINT_dup(src->pub_key, src->group);
186 if (dest->pub_key == NULL) {
187 return NULL;
188 }
189 }
190
191 /* copy the private key */
192 if (src->priv_key) {
193 if (dest->priv_key == NULL) {
194 dest->priv_key = BN_new();
195 if (dest->priv_key == NULL) {
196 return NULL;
197 }
198 }
199 if (!BN_copy(dest->priv_key, src->priv_key)) {
200 return NULL;
201 }
202 }
203 /* copy method/extra data */
204 if (src->ecdsa_meth) {
205 METHOD_unref(dest->ecdsa_meth);
206 dest->ecdsa_meth = src->ecdsa_meth;
207 METHOD_ref(dest->ecdsa_meth);
208 }
209 CRYPTO_free_ex_data(&g_ex_data_class, dest, &dest->ex_data);
210 if (!CRYPTO_dup_ex_data(&g_ex_data_class, &dest->ex_data,
211 &src->ex_data)) {
212 return NULL;
213 }
214
215 /* copy the rest */
216 dest->enc_flag = src->enc_flag;
217 dest->conv_form = src->conv_form;
218 dest->version = src->version;
219 dest->flags = src->flags;
220
221 return dest;
222 }
223
EC_KEY_dup(const EC_KEY * ec_key)224 EC_KEY *EC_KEY_dup(const EC_KEY *ec_key) {
225 EC_KEY *ret = EC_KEY_new();
226 if (ret == NULL) {
227 return NULL;
228 }
229 if (EC_KEY_copy(ret, ec_key) == NULL) {
230 EC_KEY_free(ret);
231 return NULL;
232 }
233 return ret;
234 }
235
EC_KEY_up_ref(EC_KEY * r)236 int EC_KEY_up_ref(EC_KEY *r) {
237 CRYPTO_refcount_inc(&r->references);
238 return 1;
239 }
240
EC_KEY_is_opaque(const EC_KEY * key)241 int EC_KEY_is_opaque(const EC_KEY *key) {
242 return key->ecdsa_meth && (key->ecdsa_meth->flags & ECDSA_FLAG_OPAQUE);
243 }
244
EC_KEY_get0_group(const EC_KEY * key)245 const EC_GROUP *EC_KEY_get0_group(const EC_KEY *key) { return key->group; }
246
EC_KEY_set_group(EC_KEY * key,const EC_GROUP * group)247 int EC_KEY_set_group(EC_KEY *key, const EC_GROUP *group) {
248 EC_GROUP_free(key->group);
249 /* TODO(fork): duplicating the group seems wasteful but see
250 * |EC_KEY_set_conv_form|. */
251 key->group = EC_GROUP_dup(group);
252 return (key->group == NULL) ? 0 : 1;
253 }
254
EC_KEY_get0_private_key(const EC_KEY * key)255 const BIGNUM *EC_KEY_get0_private_key(const EC_KEY *key) {
256 return key->priv_key;
257 }
258
EC_KEY_set_private_key(EC_KEY * key,const BIGNUM * priv_key)259 int EC_KEY_set_private_key(EC_KEY *key, const BIGNUM *priv_key) {
260 BN_clear_free(key->priv_key);
261 key->priv_key = BN_dup(priv_key);
262 return (key->priv_key == NULL) ? 0 : 1;
263 }
264
EC_KEY_get0_public_key(const EC_KEY * key)265 const EC_POINT *EC_KEY_get0_public_key(const EC_KEY *key) {
266 return key->pub_key;
267 }
268
EC_KEY_set_public_key(EC_KEY * key,const EC_POINT * pub_key)269 int EC_KEY_set_public_key(EC_KEY *key, const EC_POINT *pub_key) {
270 EC_POINT_free(key->pub_key);
271 key->pub_key = EC_POINT_dup(pub_key, key->group);
272 return (key->pub_key == NULL) ? 0 : 1;
273 }
274
EC_KEY_get_enc_flags(const EC_KEY * key)275 unsigned int EC_KEY_get_enc_flags(const EC_KEY *key) { return key->enc_flag; }
276
EC_KEY_set_enc_flags(EC_KEY * key,unsigned int flags)277 void EC_KEY_set_enc_flags(EC_KEY *key, unsigned int flags) {
278 key->enc_flag = flags;
279 }
280
EC_KEY_get_conv_form(const EC_KEY * key)281 point_conversion_form_t EC_KEY_get_conv_form(const EC_KEY *key) {
282 return key->conv_form;
283 }
284
EC_KEY_set_conv_form(EC_KEY * key,point_conversion_form_t cform)285 void EC_KEY_set_conv_form(EC_KEY *key, point_conversion_form_t cform) {
286 key->conv_form = cform;
287 }
288
EC_KEY_precompute_mult(EC_KEY * key,BN_CTX * ctx)289 int EC_KEY_precompute_mult(EC_KEY *key, BN_CTX *ctx) {
290 if (key->group == NULL) {
291 return 0;
292 }
293 return EC_GROUP_precompute_mult(key->group, ctx);
294 }
295
EC_KEY_check_key(const EC_KEY * eckey)296 int EC_KEY_check_key(const EC_KEY *eckey) {
297 int ok = 0;
298 BN_CTX *ctx = NULL;
299 const BIGNUM *order = NULL;
300 EC_POINT *point = NULL;
301
302 if (!eckey || !eckey->group || !eckey->pub_key) {
303 OPENSSL_PUT_ERROR(EC, EC_KEY_check_key, 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_KEY_check_key, EC_R_POINT_AT_INFINITY);
309 goto err;
310 }
311
312 ctx = BN_CTX_new();
313 point = EC_POINT_new(eckey->group);
314
315 if (ctx == NULL ||
316 point == NULL) {
317 goto err;
318 }
319
320 /* testing whether the pub_key is on the elliptic curve */
321 if (!EC_POINT_is_on_curve(eckey->group, eckey->pub_key, ctx)) {
322 OPENSSL_PUT_ERROR(EC, EC_KEY_check_key, EC_R_POINT_IS_NOT_ON_CURVE);
323 goto err;
324 }
325 /* testing whether pub_key * order is the point at infinity */
326 /* TODO(fork): can this be skipped if the cofactor is one or if we're about
327 * to check the private key, below? */
328 order = &eckey->group->order;
329 if (BN_is_zero(order)) {
330 OPENSSL_PUT_ERROR(EC, EC_KEY_check_key, EC_R_INVALID_GROUP_ORDER);
331 goto err;
332 }
333 if (!EC_POINT_mul(eckey->group, point, NULL, eckey->pub_key, order, ctx)) {
334 OPENSSL_PUT_ERROR(EC, EC_KEY_check_key, ERR_R_EC_LIB);
335 goto err;
336 }
337 if (!EC_POINT_is_at_infinity(eckey->group, point)) {
338 OPENSSL_PUT_ERROR(EC, EC_KEY_check_key, EC_R_WRONG_ORDER);
339 goto err;
340 }
341 /* in case the priv_key is present :
342 * check if generator * priv_key == pub_key
343 */
344 if (eckey->priv_key) {
345 if (BN_cmp(eckey->priv_key, order) >= 0) {
346 OPENSSL_PUT_ERROR(EC, EC_KEY_check_key, EC_R_WRONG_ORDER);
347 goto err;
348 }
349 if (!EC_POINT_mul(eckey->group, point, eckey->priv_key, NULL, NULL, ctx)) {
350 OPENSSL_PUT_ERROR(EC, EC_KEY_check_key, ERR_R_EC_LIB);
351 goto err;
352 }
353 if (EC_POINT_cmp(eckey->group, point, eckey->pub_key, ctx) != 0) {
354 OPENSSL_PUT_ERROR(EC, EC_KEY_check_key, EC_R_INVALID_PRIVATE_KEY);
355 goto err;
356 }
357 }
358 ok = 1;
359
360 err:
361 BN_CTX_free(ctx);
362 EC_POINT_free(point);
363 return ok;
364 }
365
EC_KEY_set_public_key_affine_coordinates(EC_KEY * key,BIGNUM * x,BIGNUM * y)366 int EC_KEY_set_public_key_affine_coordinates(EC_KEY *key, BIGNUM *x,
367 BIGNUM *y) {
368 BN_CTX *ctx = NULL;
369 BIGNUM *tx, *ty;
370 EC_POINT *point = NULL;
371 int ok = 0;
372
373 if (!key || !key->group || !x || !y) {
374 OPENSSL_PUT_ERROR(EC, EC_KEY_set_public_key_affine_coordinates,
375 ERR_R_PASSED_NULL_PARAMETER);
376 return 0;
377 }
378 ctx = BN_CTX_new();
379 point = EC_POINT_new(key->group);
380
381 if (ctx == NULL ||
382 point == NULL) {
383 goto err;
384 }
385
386 tx = BN_CTX_get(ctx);
387 ty = BN_CTX_get(ctx);
388
389 if (!EC_POINT_set_affine_coordinates_GFp(key->group, point, x, y, ctx) ||
390 !EC_POINT_get_affine_coordinates_GFp(key->group, point, tx, ty, ctx)) {
391 goto err;
392 }
393
394 /* Check if retrieved coordinates match originals: if not values
395 * are out of range. */
396 if (BN_cmp(x, tx) || BN_cmp(y, ty)) {
397 OPENSSL_PUT_ERROR(EC, EC_KEY_set_public_key_affine_coordinates,
398 EC_R_COORDINATES_OUT_OF_RANGE);
399 goto err;
400 }
401
402 if (!EC_KEY_set_public_key(key, point)) {
403 goto err;
404 }
405
406 if (EC_KEY_check_key(key) == 0) {
407 goto err;
408 }
409
410 ok = 1;
411
412 err:
413 BN_CTX_free(ctx);
414 EC_POINT_free(point);
415 return ok;
416 }
417
EC_KEY_generate_key(EC_KEY * eckey)418 int EC_KEY_generate_key(EC_KEY *eckey) {
419 int ok = 0;
420 BN_CTX *ctx = NULL;
421 BIGNUM *priv_key = NULL, *order = NULL;
422 EC_POINT *pub_key = NULL;
423
424 if (!eckey || !eckey->group) {
425 OPENSSL_PUT_ERROR(EC, EC_KEY_generate_key, ERR_R_PASSED_NULL_PARAMETER);
426 return 0;
427 }
428
429 order = BN_new();
430 ctx = BN_CTX_new();
431
432 if (order == NULL ||
433 ctx == NULL) {
434 goto err;
435 }
436
437 if (eckey->priv_key == NULL) {
438 priv_key = BN_new();
439 if (priv_key == NULL) {
440 goto err;
441 }
442 } else {
443 priv_key = eckey->priv_key;
444 }
445
446 if (!EC_GROUP_get_order(eckey->group, order, ctx)) {
447 goto err;
448 }
449
450 do {
451 if (!BN_rand_range(priv_key, order)) {
452 goto err;
453 }
454 } while (BN_is_zero(priv_key));
455
456 if (eckey->pub_key == NULL) {
457 pub_key = EC_POINT_new(eckey->group);
458 if (pub_key == NULL) {
459 goto err;
460 }
461 } else {
462 pub_key = eckey->pub_key;
463 }
464
465 if (!EC_POINT_mul(eckey->group, pub_key, priv_key, NULL, NULL, ctx)) {
466 goto err;
467 }
468
469 eckey->priv_key = priv_key;
470 eckey->pub_key = pub_key;
471
472 ok = 1;
473
474 err:
475 BN_free(order);
476 if (eckey->pub_key == NULL) {
477 EC_POINT_free(pub_key);
478 }
479 if (eckey->priv_key == NULL) {
480 BN_free(priv_key);
481 }
482 BN_CTX_free(ctx);
483 return ok;
484 }
485
EC_KEY_get_ex_new_index(long argl,void * argp,CRYPTO_EX_new * new_func,CRYPTO_EX_dup * dup_func,CRYPTO_EX_free * free_func)486 int EC_KEY_get_ex_new_index(long argl, void *argp, CRYPTO_EX_new *new_func,
487 CRYPTO_EX_dup *dup_func,
488 CRYPTO_EX_free *free_func) {
489 int index;
490 if (!CRYPTO_get_ex_new_index(&g_ex_data_class, &index, argl, argp, new_func,
491 dup_func, free_func)) {
492 return -1;
493 }
494 return index;
495 }
496
EC_KEY_set_ex_data(EC_KEY * d,int idx,void * arg)497 int EC_KEY_set_ex_data(EC_KEY *d, int idx, void *arg) {
498 return CRYPTO_set_ex_data(&d->ex_data, idx, arg);
499 }
500
EC_KEY_get_ex_data(const EC_KEY * d,int idx)501 void *EC_KEY_get_ex_data(const EC_KEY *d, int idx) {
502 return CRYPTO_get_ex_data(&d->ex_data, idx);
503 }
504
EC_KEY_set_asn1_flag(EC_KEY * key,int flag)505 void EC_KEY_set_asn1_flag(EC_KEY *key, int flag) {}
506