ec_key.c revision 279265
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@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@cryptsoft.com). This product includes software written by Tim 55 * Hudson (tjh@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 68EC_KEY *EC_KEY_new(void) 69 { 70 EC_KEY *ret; 71 72 ret=(EC_KEY *)OPENSSL_malloc(sizeof(EC_KEY)); 73 if (ret == NULL) 74 { 75 ECerr(EC_F_EC_KEY_NEW, ERR_R_MALLOC_FAILURE); 76 return(NULL); 77 } 78 79 ret->version = 1; 80 ret->group = NULL; 81 ret->pub_key = NULL; 82 ret->priv_key= NULL; 83 ret->enc_flag= 0; 84 ret->conv_form = POINT_CONVERSION_UNCOMPRESSED; 85 ret->references= 1; 86 ret->method_data = NULL; 87 return(ret); 88 } 89 90EC_KEY *EC_KEY_new_by_curve_name(int nid) 91 { 92 EC_KEY *ret = EC_KEY_new(); 93 if (ret == NULL) 94 return NULL; 95 ret->group = EC_GROUP_new_by_curve_name(nid); 96 if (ret->group == NULL) 97 { 98 EC_KEY_free(ret); 99 return NULL; 100 } 101 return ret; 102 } 103 104void EC_KEY_free(EC_KEY *r) 105 { 106 int i; 107 108 if (r == NULL) return; 109 110 i=CRYPTO_add(&r->references,-1,CRYPTO_LOCK_EC); 111#ifdef REF_PRINT 112 REF_PRINT("EC_KEY",r); 113#endif 114 if (i > 0) return; 115#ifdef REF_CHECK 116 if (i < 0) 117 { 118 fprintf(stderr,"EC_KEY_free, bad reference count\n"); 119 abort(); 120 } 121#endif 122 123 if (r->group != NULL) 124 EC_GROUP_free(r->group); 125 if (r->pub_key != NULL) 126 EC_POINT_free(r->pub_key); 127 if (r->priv_key != NULL) 128 BN_clear_free(r->priv_key); 129 130 EC_EX_DATA_free_all_data(&r->method_data); 131 132 OPENSSL_cleanse((void *)r, sizeof(EC_KEY)); 133 134 OPENSSL_free(r); 135 } 136 137EC_KEY *EC_KEY_copy(EC_KEY *dest, const EC_KEY *src) 138 { 139 EC_EXTRA_DATA *d; 140 141 if (dest == NULL || src == NULL) 142 { 143 ECerr(EC_F_EC_KEY_COPY, ERR_R_PASSED_NULL_PARAMETER); 144 return NULL; 145 } 146 /* copy the parameters */ 147 if (src->group) 148 { 149 const EC_METHOD *meth = EC_GROUP_method_of(src->group); 150 /* clear the old group */ 151 if (dest->group) 152 EC_GROUP_free(dest->group); 153 dest->group = EC_GROUP_new(meth); 154 if (dest->group == NULL) 155 return NULL; 156 if (!EC_GROUP_copy(dest->group, src->group)) 157 return NULL; 158 } 159 /* copy the public key */ 160 if (src->pub_key && src->group) 161 { 162 if (dest->pub_key) 163 EC_POINT_free(dest->pub_key); 164 dest->pub_key = EC_POINT_new(src->group); 165 if (dest->pub_key == NULL) 166 return NULL; 167 if (!EC_POINT_copy(dest->pub_key, src->pub_key)) 168 return NULL; 169 } 170 /* copy the private key */ 171 if (src->priv_key) 172 { 173 if (dest->priv_key == NULL) 174 { 175 dest->priv_key = BN_new(); 176 if (dest->priv_key == NULL) 177 return NULL; 178 } 179 if (!BN_copy(dest->priv_key, src->priv_key)) 180 return NULL; 181 } 182 /* copy method/extra data */ 183 EC_EX_DATA_free_all_data(&dest->method_data); 184 185 for (d = src->method_data; d != NULL; d = d->next) 186 { 187 void *t = d->dup_func(d->data); 188 189 if (t == NULL) 190 return 0; 191 if (!EC_EX_DATA_set_data(&dest->method_data, t, d->dup_func, d->free_func, d->clear_free_func)) 192 return 0; 193 } 194 195 /* copy the rest */ 196 dest->enc_flag = src->enc_flag; 197 dest->conv_form = src->conv_form; 198 dest->version = src->version; 199 200 return dest; 201 } 202 203EC_KEY *EC_KEY_dup(const EC_KEY *ec_key) 204 { 205 EC_KEY *ret = EC_KEY_new(); 206 if (ret == NULL) 207 return NULL; 208 if (EC_KEY_copy(ret, ec_key) == NULL) 209 { 210 EC_KEY_free(ret); 211 return NULL; 212 } 213 return ret; 214 } 215 216int EC_KEY_up_ref(EC_KEY *r) 217 { 218 int i = CRYPTO_add(&r->references, 1, CRYPTO_LOCK_EC); 219#ifdef REF_PRINT 220 REF_PRINT("EC_KEY",r); 221#endif 222#ifdef REF_CHECK 223 if (i < 2) 224 { 225 fprintf(stderr, "EC_KEY_up, bad reference count\n"); 226 abort(); 227 } 228#endif 229 return ((i > 1) ? 1 : 0); 230 } 231 232int EC_KEY_generate_key(EC_KEY *eckey) 233 { 234 int ok = 0; 235 BN_CTX *ctx = NULL; 236 BIGNUM *priv_key = NULL, *order = NULL; 237 EC_POINT *pub_key = NULL; 238 239 if (!eckey || !eckey->group) 240 { 241 ECerr(EC_F_EC_KEY_GENERATE_KEY, ERR_R_PASSED_NULL_PARAMETER); 242 return 0; 243 } 244 245 if ((order = BN_new()) == NULL) goto err; 246 if ((ctx = BN_CTX_new()) == NULL) goto err; 247 248 if (eckey->priv_key == NULL) 249 { 250 priv_key = BN_new(); 251 if (priv_key == NULL) 252 goto err; 253 } 254 else 255 priv_key = eckey->priv_key; 256 257 if (!EC_GROUP_get_order(eckey->group, order, ctx)) 258 goto err; 259 260 do 261 if (!BN_rand_range(priv_key, order)) 262 goto err; 263 while (BN_is_zero(priv_key)); 264 265 if (eckey->pub_key == NULL) 266 { 267 pub_key = EC_POINT_new(eckey->group); 268 if (pub_key == NULL) 269 goto err; 270 } 271 else 272 pub_key = eckey->pub_key; 273 274 if (!EC_POINT_mul(eckey->group, pub_key, priv_key, NULL, NULL, ctx)) 275 goto err; 276 277 eckey->priv_key = priv_key; 278 eckey->pub_key = pub_key; 279 280 ok=1; 281 282err: 283 if (order) 284 BN_free(order); 285 if (pub_key != NULL && eckey->pub_key == NULL) 286 EC_POINT_free(pub_key); 287 if (priv_key != NULL && eckey->priv_key == NULL) 288 BN_free(priv_key); 289 if (ctx != NULL) 290 BN_CTX_free(ctx); 291 return(ok); 292 } 293 294int EC_KEY_check_key(const EC_KEY *eckey) 295 { 296 int ok = 0; 297 BN_CTX *ctx = NULL; 298 const BIGNUM *order = NULL; 299 EC_POINT *point = NULL; 300 301 if (!eckey || !eckey->group || !eckey->pub_key) 302 { 303 ECerr(EC_F_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 { 309 ECerr(EC_F_EC_KEY_CHECK_KEY, EC_R_POINT_AT_INFINITY); 310 goto err; 311 } 312 313 if ((ctx = BN_CTX_new()) == NULL) 314 goto err; 315 if ((point = EC_POINT_new(eckey->group)) == NULL) 316 goto err; 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 { 321 ECerr(EC_F_EC_KEY_CHECK_KEY, EC_R_POINT_IS_NOT_ON_CURVE); 322 goto err; 323 } 324 /* testing whether pub_key * order is the point at infinity */ 325 order = &eckey->group->order; 326 if (BN_is_zero(order)) 327 { 328 ECerr(EC_F_EC_KEY_CHECK_KEY, EC_R_INVALID_GROUP_ORDER); 329 goto err; 330 } 331 if (!EC_POINT_mul(eckey->group, point, NULL, eckey->pub_key, order, ctx)) 332 { 333 ECerr(EC_F_EC_KEY_CHECK_KEY, ERR_R_EC_LIB); 334 goto err; 335 } 336 if (!EC_POINT_is_at_infinity(eckey->group, point)) 337 { 338 ECerr(EC_F_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 { 346 if (BN_cmp(eckey->priv_key, order) >= 0) 347 { 348 ECerr(EC_F_EC_KEY_CHECK_KEY, EC_R_WRONG_ORDER); 349 goto err; 350 } 351 if (!EC_POINT_mul(eckey->group, point, eckey->priv_key, 352 NULL, NULL, ctx)) 353 { 354 ECerr(EC_F_EC_KEY_CHECK_KEY, ERR_R_EC_LIB); 355 goto err; 356 } 357 if (EC_POINT_cmp(eckey->group, point, eckey->pub_key, 358 ctx) != 0) 359 { 360 ECerr(EC_F_EC_KEY_CHECK_KEY, EC_R_INVALID_PRIVATE_KEY); 361 goto err; 362 } 363 } 364 ok = 1; 365err: 366 if (ctx != NULL) 367 BN_CTX_free(ctx); 368 if (point != NULL) 369 EC_POINT_free(point); 370 return(ok); 371 } 372 373const EC_GROUP *EC_KEY_get0_group(const EC_KEY *key) 374 { 375 return key->group; 376 } 377 378int EC_KEY_set_group(EC_KEY *key, const EC_GROUP *group) 379 { 380 if (key->group != NULL) 381 EC_GROUP_free(key->group); 382 key->group = EC_GROUP_dup(group); 383 return (key->group == NULL) ? 0 : 1; 384 } 385 386const BIGNUM *EC_KEY_get0_private_key(const EC_KEY *key) 387 { 388 return key->priv_key; 389 } 390 391int EC_KEY_set_private_key(EC_KEY *key, const BIGNUM *priv_key) 392 { 393 if (key->priv_key) 394 BN_clear_free(key->priv_key); 395 key->priv_key = BN_dup(priv_key); 396 return (key->priv_key == NULL) ? 0 : 1; 397 } 398 399const EC_POINT *EC_KEY_get0_public_key(const EC_KEY *key) 400 { 401 return key->pub_key; 402 } 403 404int EC_KEY_set_public_key(EC_KEY *key, const EC_POINT *pub_key) 405 { 406 if (key->pub_key != NULL) 407 EC_POINT_free(key->pub_key); 408 key->pub_key = EC_POINT_dup(pub_key, key->group); 409 return (key->pub_key == NULL) ? 0 : 1; 410 } 411 412unsigned int EC_KEY_get_enc_flags(const EC_KEY *key) 413 { 414 return key->enc_flag; 415 } 416 417void EC_KEY_set_enc_flags(EC_KEY *key, unsigned int flags) 418 { 419 key->enc_flag = flags; 420 } 421 422point_conversion_form_t EC_KEY_get_conv_form(const EC_KEY *key) 423 { 424 return key->conv_form; 425 } 426 427void EC_KEY_set_conv_form(EC_KEY *key, point_conversion_form_t cform) 428 { 429 key->conv_form = cform; 430 if (key->group != NULL) 431 EC_GROUP_set_point_conversion_form(key->group, cform); 432 } 433 434void *EC_KEY_get_key_method_data(EC_KEY *key, 435 void *(*dup_func)(void *), void (*free_func)(void *), void (*clear_free_func)(void *)) 436 { 437 void *ret; 438 439 CRYPTO_r_lock(CRYPTO_LOCK_EC); 440 ret = EC_EX_DATA_get_data(key->method_data, dup_func, free_func, clear_free_func); 441 CRYPTO_r_unlock(CRYPTO_LOCK_EC); 442 443 return ret; 444 } 445 446void *EC_KEY_insert_key_method_data(EC_KEY *key, void *data, 447 void *(*dup_func)(void *), void (*free_func)(void *), void (*clear_free_func)(void *)) 448 { 449 EC_EXTRA_DATA *ex_data; 450 451 CRYPTO_w_lock(CRYPTO_LOCK_EC); 452 ex_data = EC_EX_DATA_get_data(key->method_data, dup_func, free_func, clear_free_func); 453 if (ex_data == NULL) 454 EC_EX_DATA_set_data(&key->method_data, data, dup_func, free_func, clear_free_func); 455 CRYPTO_w_unlock(CRYPTO_LOCK_EC); 456 457 return ex_data; 458 } 459 460void EC_KEY_set_asn1_flag(EC_KEY *key, int flag) 461 { 462 if (key->group != NULL) 463 EC_GROUP_set_asn1_flag(key->group, flag); 464 } 465 466int EC_KEY_precompute_mult(EC_KEY *key, BN_CTX *ctx) 467 { 468 if (key->group == NULL) 469 return 0; 470 return EC_GROUP_precompute_mult(key->group, ctx); 471 } 472