1 /* crypto/ec/ec_key.c */ 2 /* 3 * Written by Nils Larsch for the OpenSSL project. 4 */ 5 /* ==================================================================== 6 * Copyright (c) 1998-2005 The OpenSSL Project. All rights reserved. 7 * 8 * Redistribution and use in source and binary forms, with or without 9 * modification, are permitted provided that the following conditions 10 * are met: 11 * 12 * 1. Redistributions of source code must retain the above copyright 13 * notice, this list of conditions and the following disclaimer. 14 * 15 * 2. Redistributions in binary form must reproduce the above copyright 16 * notice, this list of conditions and the following disclaimer in 17 * the documentation and/or other materials provided with the 18 * distribution. 19 * 20 * 3. All advertising materials mentioning features or use of this 21 * software must display the following acknowledgment: 22 * "This product includes software developed by the OpenSSL Project 23 * for use in the OpenSSL Toolkit. (http://www.openssl.org/)" 24 * 25 * 4. The names "OpenSSL Toolkit" and "OpenSSL Project" must not be used to 26 * endorse or promote products derived from this software without 27 * prior written permission. For written permission, please contact 28 * openssl-core (at) openssl.org. 29 * 30 * 5. Products derived from this software may not be called "OpenSSL" 31 * nor may "OpenSSL" appear in their names without prior written 32 * permission of the OpenSSL Project. 33 * 34 * 6. Redistributions of any form whatsoever must retain the following 35 * acknowledgment: 36 * "This product includes software developed by the OpenSSL Project 37 * for use in the OpenSSL Toolkit (http://www.openssl.org/)" 38 * 39 * THIS SOFTWARE IS PROVIDED BY THE OpenSSL PROJECT ``AS IS'' AND ANY 40 * EXPRESSED OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE 41 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR 42 * PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE OpenSSL PROJECT OR 43 * ITS CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, 44 * SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT 45 * NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; 46 * LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) 47 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, 48 * STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) 49 * ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED 50 * OF THE POSSIBILITY OF SUCH DAMAGE. 51 * ==================================================================== 52 * 53 * This product includes cryptographic software written by Eric Young 54 * (eay (at) cryptsoft.com). This product includes software written by Tim 55 * Hudson (tjh (at) cryptsoft.com). 56 * 57 */ 58 /* ==================================================================== 59 * Copyright 2002 Sun Microsystems, Inc. ALL RIGHTS RESERVED. 60 * Portions originally developed by SUN MICROSYSTEMS, INC., and 61 * contributed to the OpenSSL project. 62 */ 63 64 #include <string.h> 65 #include "ec_lcl.h" 66 #include <openssl/err.h> 67 #ifdef OPENSSL_FIPS 68 #include <openssl/fips.h> 69 #endif 70 71 EC_KEY *EC_KEY_new(void) 72 { 73 EC_KEY *ret; 74 75 ret=(EC_KEY *)OPENSSL_malloc(sizeof(EC_KEY)); 76 if (ret == NULL) 77 { 78 ECerr(EC_F_EC_KEY_NEW, ERR_R_MALLOC_FAILURE); 79 return(NULL); 80 } 81 82 ret->version = 1; 83 ret->flags = 0; 84 ret->group = NULL; 85 ret->pub_key = NULL; 86 ret->priv_key= NULL; 87 ret->enc_flag= 0; 88 ret->conv_form = POINT_CONVERSION_UNCOMPRESSED; 89 ret->references= 1; 90 ret->method_data = NULL; 91 return(ret); 92 } 93 94 EC_KEY *EC_KEY_new_by_curve_name(int nid) 95 { 96 EC_KEY *ret = EC_KEY_new(); 97 if (ret == NULL) 98 return NULL; 99 ret->group = EC_GROUP_new_by_curve_name(nid); 100 if (ret->group == NULL) 101 { 102 EC_KEY_free(ret); 103 return NULL; 104 } 105 return ret; 106 } 107 108 void EC_KEY_free(EC_KEY *r) 109 { 110 int i; 111 112 if (r == NULL) return; 113 114 i=CRYPTO_add(&r->references,-1,CRYPTO_LOCK_EC); 115 #ifdef REF_PRINT 116 REF_PRINT("EC_KEY",r); 117 #endif 118 if (i > 0) return; 119 #ifdef REF_CHECK 120 if (i < 0) 121 { 122 fprintf(stderr,"EC_KEY_free, bad reference count\n"); 123 abort(); 124 } 125 #endif 126 127 if (r->group != NULL) 128 EC_GROUP_free(r->group); 129 if (r->pub_key != NULL) 130 EC_POINT_free(r->pub_key); 131 if (r->priv_key != NULL) 132 BN_clear_free(r->priv_key); 133 134 EC_EX_DATA_free_all_data(&r->method_data); 135 136 OPENSSL_cleanse((void *)r, sizeof(EC_KEY)); 137 138 OPENSSL_free(r); 139 } 140 141 EC_KEY *EC_KEY_copy(EC_KEY *dest, const EC_KEY *src) 142 { 143 EC_EXTRA_DATA *d; 144 145 if (dest == NULL || src == NULL) 146 { 147 ECerr(EC_F_EC_KEY_COPY, ERR_R_PASSED_NULL_PARAMETER); 148 return NULL; 149 } 150 /* copy the parameters */ 151 if (src->group) 152 { 153 const EC_METHOD *meth = EC_GROUP_method_of(src->group); 154 /* clear the old group */ 155 if (dest->group) 156 EC_GROUP_free(dest->group); 157 dest->group = EC_GROUP_new(meth); 158 if (dest->group == NULL) 159 return NULL; 160 if (!EC_GROUP_copy(dest->group, src->group)) 161 return NULL; 162 } 163 /* copy the public key */ 164 if (src->pub_key && src->group) 165 { 166 if (dest->pub_key) 167 EC_POINT_free(dest->pub_key); 168 dest->pub_key = EC_POINT_new(src->group); 169 if (dest->pub_key == NULL) 170 return NULL; 171 if (!EC_POINT_copy(dest->pub_key, src->pub_key)) 172 return NULL; 173 } 174 /* copy the private key */ 175 if (src->priv_key) 176 { 177 if (dest->priv_key == NULL) 178 { 179 dest->priv_key = BN_new(); 180 if (dest->priv_key == NULL) 181 return NULL; 182 } 183 if (!BN_copy(dest->priv_key, src->priv_key)) 184 return NULL; 185 } 186 /* copy method/extra data */ 187 EC_EX_DATA_free_all_data(&dest->method_data); 188 189 for (d = src->method_data; d != NULL; d = d->next) 190 { 191 void *t = d->dup_func(d->data); 192 193 if (t == NULL) 194 return 0; 195 if (!EC_EX_DATA_set_data(&dest->method_data, t, d->dup_func, d->free_func, d->clear_free_func)) 196 return 0; 197 } 198 199 /* copy the rest */ 200 dest->enc_flag = src->enc_flag; 201 dest->conv_form = src->conv_form; 202 dest->version = src->version; 203 dest->flags = src->flags; 204 205 return dest; 206 } 207 208 EC_KEY *EC_KEY_dup(const EC_KEY *ec_key) 209 { 210 EC_KEY *ret = EC_KEY_new(); 211 if (ret == NULL) 212 return NULL; 213 if (EC_KEY_copy(ret, ec_key) == NULL) 214 { 215 EC_KEY_free(ret); 216 return NULL; 217 } 218 return ret; 219 } 220 221 int EC_KEY_up_ref(EC_KEY *r) 222 { 223 int i = CRYPTO_add(&r->references, 1, CRYPTO_LOCK_EC); 224 #ifdef REF_PRINT 225 REF_PRINT("EC_KEY",r); 226 #endif 227 #ifdef REF_CHECK 228 if (i < 2) 229 { 230 fprintf(stderr, "EC_KEY_up, bad reference count\n"); 231 abort(); 232 } 233 #endif 234 return ((i > 1) ? 1 : 0); 235 } 236 237 int EC_KEY_generate_key(EC_KEY *eckey) 238 { 239 int ok = 0; 240 BN_CTX *ctx = NULL; 241 BIGNUM *priv_key = NULL, *order = NULL; 242 EC_POINT *pub_key = NULL; 243 244 #ifdef OPENSSL_FIPS 245 if (FIPS_mode()) 246 return FIPS_ec_key_generate_key(eckey); 247 #endif 248 249 if (!eckey || !eckey->group) 250 { 251 ECerr(EC_F_EC_KEY_GENERATE_KEY, ERR_R_PASSED_NULL_PARAMETER); 252 return 0; 253 } 254 255 if ((order = BN_new()) == NULL) goto err; 256 if ((ctx = BN_CTX_new()) == NULL) goto err; 257 258 if (eckey->priv_key == NULL) 259 { 260 priv_key = BN_new(); 261 if (priv_key == NULL) 262 goto err; 263 } 264 else 265 priv_key = eckey->priv_key; 266 267 if (!EC_GROUP_get_order(eckey->group, order, ctx)) 268 goto err; 269 270 do 271 if (!BN_rand_range(priv_key, order)) 272 goto err; 273 while (BN_is_zero(priv_key)); 274 275 if (eckey->pub_key == NULL) 276 { 277 pub_key = EC_POINT_new(eckey->group); 278 if (pub_key == NULL) 279 goto err; 280 } 281 else 282 pub_key = eckey->pub_key; 283 284 if (!EC_POINT_mul(eckey->group, pub_key, priv_key, NULL, NULL, ctx)) 285 goto err; 286 287 eckey->priv_key = priv_key; 288 eckey->pub_key = pub_key; 289 290 ok=1; 291 292 err: 293 if (order) 294 BN_free(order); 295 if (pub_key != NULL && eckey->pub_key == NULL) 296 EC_POINT_free(pub_key); 297 if (priv_key != NULL && eckey->priv_key == NULL) 298 BN_free(priv_key); 299 if (ctx != NULL) 300 BN_CTX_free(ctx); 301 return(ok); 302 } 303 304 int EC_KEY_check_key(const EC_KEY *eckey) 305 { 306 int ok = 0; 307 BN_CTX *ctx = NULL; 308 const BIGNUM *order = NULL; 309 EC_POINT *point = NULL; 310 311 if (!eckey || !eckey->group || !eckey->pub_key) 312 { 313 ECerr(EC_F_EC_KEY_CHECK_KEY, ERR_R_PASSED_NULL_PARAMETER); 314 return 0; 315 } 316 317 if (EC_POINT_is_at_infinity(eckey->group, eckey->pub_key)) 318 { 319 ECerr(EC_F_EC_KEY_CHECK_KEY, EC_R_POINT_AT_INFINITY); 320 goto err; 321 } 322 323 if ((ctx = BN_CTX_new()) == NULL) 324 goto err; 325 if ((point = EC_POINT_new(eckey->group)) == NULL) 326 goto err; 327 328 /* testing whether the pub_key is on the elliptic curve */ 329 if (!EC_POINT_is_on_curve(eckey->group, eckey->pub_key, ctx)) 330 { 331 ECerr(EC_F_EC_KEY_CHECK_KEY, EC_R_POINT_IS_NOT_ON_CURVE); 332 goto err; 333 } 334 /* testing whether pub_key * order is the point at infinity */ 335 order = &eckey->group->order; 336 if (BN_is_zero(order)) 337 { 338 ECerr(EC_F_EC_KEY_CHECK_KEY, EC_R_INVALID_GROUP_ORDER); 339 goto err; 340 } 341 if (!EC_POINT_mul(eckey->group, point, NULL, eckey->pub_key, order, ctx)) 342 { 343 ECerr(EC_F_EC_KEY_CHECK_KEY, ERR_R_EC_LIB); 344 goto err; 345 } 346 if (!EC_POINT_is_at_infinity(eckey->group, point)) 347 { 348 ECerr(EC_F_EC_KEY_CHECK_KEY, EC_R_WRONG_ORDER); 349 goto err; 350 } 351 /* in case the priv_key is present : 352 * check if generator * priv_key == pub_key 353 */ 354 if (eckey->priv_key) 355 { 356 if (BN_cmp(eckey->priv_key, order) >= 0) 357 { 358 ECerr(EC_F_EC_KEY_CHECK_KEY, EC_R_WRONG_ORDER); 359 goto err; 360 } 361 if (!EC_POINT_mul(eckey->group, point, eckey->priv_key, 362 NULL, NULL, ctx)) 363 { 364 ECerr(EC_F_EC_KEY_CHECK_KEY, ERR_R_EC_LIB); 365 goto err; 366 } 367 if (EC_POINT_cmp(eckey->group, point, eckey->pub_key, 368 ctx) != 0) 369 { 370 ECerr(EC_F_EC_KEY_CHECK_KEY, EC_R_INVALID_PRIVATE_KEY); 371 goto err; 372 } 373 } 374 ok = 1; 375 err: 376 if (ctx != NULL) 377 BN_CTX_free(ctx); 378 if (point != NULL) 379 EC_POINT_free(point); 380 return(ok); 381 } 382 383 int EC_KEY_set_public_key_affine_coordinates(EC_KEY *key, BIGNUM *x, BIGNUM *y) 384 { 385 BN_CTX *ctx = NULL; 386 BIGNUM *tx, *ty; 387 EC_POINT *point = NULL; 388 int ok = 0, tmp_nid, is_char_two = 0; 389 390 if (!key || !key->group || !x || !y) 391 { 392 ECerr(EC_F_EC_KEY_SET_PUBLIC_KEY_AFFINE_COORDINATES, 393 ERR_R_PASSED_NULL_PARAMETER); 394 return 0; 395 } 396 ctx = BN_CTX_new(); 397 if (!ctx) 398 goto err; 399 400 point = EC_POINT_new(key->group); 401 402 if (!point) 403 goto err; 404 405 tmp_nid = EC_METHOD_get_field_type(EC_GROUP_method_of(key->group)); 406 407 if (tmp_nid == NID_X9_62_characteristic_two_field) 408 is_char_two = 1; 409 410 tx = BN_CTX_get(ctx); 411 ty = BN_CTX_get(ctx); 412 #ifndef OPENSSL_NO_EC2M 413 if (is_char_two) 414 { 415 if (!EC_POINT_set_affine_coordinates_GF2m(key->group, point, 416 x, y, ctx)) 417 goto err; 418 if (!EC_POINT_get_affine_coordinates_GF2m(key->group, point, 419 tx, ty, ctx)) 420 goto err; 421 } 422 else 423 #endif 424 { 425 if (!EC_POINT_set_affine_coordinates_GFp(key->group, point, 426 x, y, ctx)) 427 goto err; 428 if (!EC_POINT_get_affine_coordinates_GFp(key->group, point, 429 tx, ty, ctx)) 430 goto err; 431 } 432 /* Check if retrieved coordinates match originals: if not values 433 * are out of range. 434 */ 435 if (BN_cmp(x, tx) || BN_cmp(y, ty)) 436 { 437 ECerr(EC_F_EC_KEY_SET_PUBLIC_KEY_AFFINE_COORDINATES, 438 EC_R_COORDINATES_OUT_OF_RANGE); 439 goto err; 440 } 441 442 if (!EC_KEY_set_public_key(key, point)) 443 goto err; 444 445 if (EC_KEY_check_key(key) == 0) 446 goto err; 447 448 ok = 1; 449 450 err: 451 if (ctx) 452 BN_CTX_free(ctx); 453 if (point) 454 EC_POINT_free(point); 455 return ok; 456 457 } 458 459 const EC_GROUP *EC_KEY_get0_group(const EC_KEY *key) 460 { 461 return key->group; 462 } 463 464 int EC_KEY_set_group(EC_KEY *key, const EC_GROUP *group) 465 { 466 if (key->group != NULL) 467 EC_GROUP_free(key->group); 468 key->group = EC_GROUP_dup(group); 469 return (key->group == NULL) ? 0 : 1; 470 } 471 472 const BIGNUM *EC_KEY_get0_private_key(const EC_KEY *key) 473 { 474 return key->priv_key; 475 } 476 477 int EC_KEY_set_private_key(EC_KEY *key, const BIGNUM *priv_key) 478 { 479 if (key->priv_key) 480 BN_clear_free(key->priv_key); 481 key->priv_key = BN_dup(priv_key); 482 return (key->priv_key == NULL) ? 0 : 1; 483 } 484 485 const EC_POINT *EC_KEY_get0_public_key(const EC_KEY *key) 486 { 487 return key->pub_key; 488 } 489 490 int EC_KEY_set_public_key(EC_KEY *key, const EC_POINT *pub_key) 491 { 492 if (key->pub_key != NULL) 493 EC_POINT_free(key->pub_key); 494 key->pub_key = EC_POINT_dup(pub_key, key->group); 495 return (key->pub_key == NULL) ? 0 : 1; 496 } 497 498 unsigned int EC_KEY_get_enc_flags(const EC_KEY *key) 499 { 500 return key->enc_flag; 501 } 502 503 void EC_KEY_set_enc_flags(EC_KEY *key, unsigned int flags) 504 { 505 key->enc_flag = flags; 506 } 507 508 point_conversion_form_t EC_KEY_get_conv_form(const EC_KEY *key) 509 { 510 return key->conv_form; 511 } 512 513 void EC_KEY_set_conv_form(EC_KEY *key, point_conversion_form_t cform) 514 { 515 key->conv_form = cform; 516 if (key->group != NULL) 517 EC_GROUP_set_point_conversion_form(key->group, cform); 518 } 519 520 void *EC_KEY_get_key_method_data(EC_KEY *key, 521 void *(*dup_func)(void *), void (*free_func)(void *), void (*clear_free_func)(void *)) 522 { 523 void *ret; 524 525 CRYPTO_r_lock(CRYPTO_LOCK_EC); 526 ret = EC_EX_DATA_get_data(key->method_data, dup_func, free_func, clear_free_func); 527 CRYPTO_r_unlock(CRYPTO_LOCK_EC); 528 529 return ret; 530 } 531 532 void *EC_KEY_insert_key_method_data(EC_KEY *key, void *data, 533 void *(*dup_func)(void *), void (*free_func)(void *), void (*clear_free_func)(void *)) 534 { 535 EC_EXTRA_DATA *ex_data; 536 537 CRYPTO_w_lock(CRYPTO_LOCK_EC); 538 ex_data = EC_EX_DATA_get_data(key->method_data, dup_func, free_func, clear_free_func); 539 if (ex_data == NULL) 540 EC_EX_DATA_set_data(&key->method_data, data, dup_func, free_func, clear_free_func); 541 CRYPTO_w_unlock(CRYPTO_LOCK_EC); 542 543 return ex_data; 544 } 545 546 void EC_KEY_set_asn1_flag(EC_KEY *key, int flag) 547 { 548 if (key->group != NULL) 549 EC_GROUP_set_asn1_flag(key->group, flag); 550 } 551 552 int EC_KEY_precompute_mult(EC_KEY *key, BN_CTX *ctx) 553 { 554 if (key->group == NULL) 555 return 0; 556 return EC_GROUP_precompute_mult(key->group, ctx); 557 } 558 559 int EC_KEY_get_flags(const EC_KEY *key) 560 { 561 return key->flags; 562 } 563 564 void EC_KEY_set_flags(EC_KEY *key, int flags) 565 { 566 key->flags |= flags; 567 } 568 569 void EC_KEY_clear_flags(EC_KEY *key, int flags) 570 { 571 key->flags &= ~flags; 572 } 573