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 #include <string.h> 68 69 EC_KEY *EC_KEY_new(void) 70 { 71 EC_KEY *ret; 72 73 ret=(EC_KEY *)OPENSSL_malloc(sizeof(EC_KEY)); 74 if (ret == NULL) 75 { 76 ECerr(EC_F_EC_KEY_NEW, ERR_R_MALLOC_FAILURE); 77 return(NULL); 78 } 79 80 ret->version = 1; 81 ret->group = NULL; 82 ret->pub_key = NULL; 83 ret->priv_key= NULL; 84 ret->enc_flag= 0; 85 ret->conv_form = POINT_CONVERSION_UNCOMPRESSED; 86 ret->references= 1; 87 ret->method_data = NULL; 88 return(ret); 89 } 90 91 EC_KEY *EC_KEY_new_by_curve_name(int nid) 92 { 93 EC_KEY *ret = EC_KEY_new(); 94 if (ret == NULL) 95 return NULL; 96 ret->group = EC_GROUP_new_by_curve_name(nid); 97 if (ret->group == NULL) 98 { 99 EC_KEY_free(ret); 100 return NULL; 101 } 102 return ret; 103 } 104 105 void EC_KEY_free(EC_KEY *r) 106 { 107 int i; 108 109 if (r == NULL) return; 110 111 i=CRYPTO_add(&r->references,-1,CRYPTO_LOCK_EC); 112 #ifdef REF_PRINT 113 REF_PRINT("EC_KEY",r); 114 #endif 115 if (i > 0) return; 116 #ifdef REF_CHECK 117 if (i < 0) 118 { 119 fprintf(stderr,"EC_KEY_free, bad reference count\n"); 120 abort(); 121 } 122 #endif 123 124 if (r->group != NULL) 125 EC_GROUP_free(r->group); 126 if (r->pub_key != NULL) 127 EC_POINT_free(r->pub_key); 128 if (r->priv_key != NULL) 129 BN_clear_free(r->priv_key); 130 131 EC_EX_DATA_free_all_data(&r->method_data); 132 133 OPENSSL_cleanse((void *)r, sizeof(EC_KEY)); 134 135 OPENSSL_free(r); 136 } 137 138 EC_KEY *EC_KEY_copy(EC_KEY *dest, const EC_KEY *src) 139 { 140 EC_EXTRA_DATA *d; 141 142 if (dest == NULL || src == NULL) 143 { 144 ECerr(EC_F_EC_KEY_COPY, ERR_R_PASSED_NULL_PARAMETER); 145 return NULL; 146 } 147 /* copy the parameters */ 148 if (src->group) 149 { 150 const EC_METHOD *meth = EC_GROUP_method_of(src->group); 151 /* clear the old group */ 152 if (dest->group) 153 EC_GROUP_free(dest->group); 154 dest->group = EC_GROUP_new(meth); 155 if (dest->group == NULL) 156 return NULL; 157 if (!EC_GROUP_copy(dest->group, src->group)) 158 return NULL; 159 } 160 /* copy the public key */ 161 if (src->pub_key && src->group) 162 { 163 if (dest->pub_key) 164 EC_POINT_free(dest->pub_key); 165 dest->pub_key = EC_POINT_new(src->group); 166 if (dest->pub_key == NULL) 167 return NULL; 168 if (!EC_POINT_copy(dest->pub_key, src->pub_key)) 169 return NULL; 170 } 171 /* copy the private key */ 172 if (src->priv_key) 173 { 174 if (dest->priv_key == NULL) 175 { 176 dest->priv_key = BN_new(); 177 if (dest->priv_key == NULL) 178 return NULL; 179 } 180 if (!BN_copy(dest->priv_key, src->priv_key)) 181 return NULL; 182 } 183 /* copy method/extra data */ 184 EC_EX_DATA_free_all_data(&dest->method_data); 185 186 for (d = src->method_data; d != NULL; d = d->next) 187 { 188 void *t = d->dup_func(d->data); 189 190 if (t == NULL) 191 return 0; 192 if (!EC_EX_DATA_set_data(&dest->method_data, t, d->dup_func, d->free_func, d->clear_free_func)) 193 return 0; 194 } 195 196 /* copy the rest */ 197 dest->enc_flag = src->enc_flag; 198 dest->conv_form = src->conv_form; 199 dest->version = src->version; 200 201 return dest; 202 } 203 204 EC_KEY *EC_KEY_dup(const EC_KEY *ec_key) 205 { 206 EC_KEY *ret = EC_KEY_new(); 207 if (ret == NULL) 208 return NULL; 209 if (EC_KEY_copy(ret, ec_key) == NULL) 210 { 211 EC_KEY_free(ret); 212 return NULL; 213 } 214 return ret; 215 } 216 217 int EC_KEY_up_ref(EC_KEY *r) 218 { 219 int i = CRYPTO_add(&r->references, 1, CRYPTO_LOCK_EC); 220 #ifdef REF_PRINT 221 REF_PRINT("EC_KEY",r); 222 #endif 223 #ifdef REF_CHECK 224 if (i < 2) 225 { 226 fprintf(stderr, "EC_KEY_up, bad reference count\n"); 227 abort(); 228 } 229 #endif 230 return ((i > 1) ? 1 : 0); 231 } 232 233 int EC_KEY_generate_key(EC_KEY *eckey) 234 { 235 int ok = 0; 236 BN_CTX *ctx = NULL; 237 BIGNUM *priv_key = NULL, *order = NULL; 238 EC_POINT *pub_key = NULL; 239 240 if (!eckey || !eckey->group) 241 { 242 ECerr(EC_F_EC_KEY_GENERATE_KEY, ERR_R_PASSED_NULL_PARAMETER); 243 return 0; 244 } 245 246 if ((order = BN_new()) == NULL) goto err; 247 if ((ctx = BN_CTX_new()) == NULL) goto err; 248 249 if (eckey->priv_key == NULL) 250 { 251 priv_key = BN_new(); 252 if (priv_key == NULL) 253 goto err; 254 } 255 else 256 priv_key = eckey->priv_key; 257 258 if (!EC_GROUP_get_order(eckey->group, order, ctx)) 259 goto err; 260 261 do 262 if (!BN_rand_range(priv_key, order)) 263 goto err; 264 while (BN_is_zero(priv_key)); 265 266 if (eckey->pub_key == NULL) 267 { 268 pub_key = EC_POINT_new(eckey->group); 269 if (pub_key == NULL) 270 goto err; 271 } 272 else 273 pub_key = eckey->pub_key; 274 275 if (!EC_POINT_mul(eckey->group, pub_key, priv_key, NULL, NULL, ctx)) 276 goto err; 277 278 eckey->priv_key = priv_key; 279 eckey->pub_key = pub_key; 280 281 ok=1; 282 283 err: 284 if (order) 285 BN_free(order); 286 if (pub_key != NULL && eckey->pub_key == NULL) 287 EC_POINT_free(pub_key); 288 if (priv_key != NULL && eckey->priv_key == NULL) 289 BN_free(priv_key); 290 if (ctx != NULL) 291 BN_CTX_free(ctx); 292 return(ok); 293 } 294 295 int EC_KEY_check_key(const EC_KEY *eckey) 296 { 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 { 304 ECerr(EC_F_EC_KEY_CHECK_KEY, ERR_R_PASSED_NULL_PARAMETER); 305 return 0; 306 } 307 308 if ((ctx = BN_CTX_new()) == NULL) 309 goto err; 310 if ((point = EC_POINT_new(eckey->group)) == NULL) 311 goto err; 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 { 316 ECerr(EC_F_EC_KEY_CHECK_KEY, EC_R_POINT_IS_NOT_ON_CURVE); 317 goto err; 318 } 319 /* testing whether pub_key * order is the point at infinity */ 320 order = &eckey->group->order; 321 if (BN_is_zero(order)) 322 { 323 ECerr(EC_F_EC_KEY_CHECK_KEY, EC_R_INVALID_GROUP_ORDER); 324 goto err; 325 } 326 if (!EC_POINT_mul(eckey->group, point, NULL, eckey->pub_key, order, ctx)) 327 { 328 ECerr(EC_F_EC_KEY_CHECK_KEY, ERR_R_EC_LIB); 329 goto err; 330 } 331 if (!EC_POINT_is_at_infinity(eckey->group, point)) 332 { 333 ECerr(EC_F_EC_KEY_CHECK_KEY, EC_R_WRONG_ORDER); 334 goto err; 335 } 336 /* in case the priv_key is present : 337 * check if generator * priv_key == pub_key 338 */ 339 if (eckey->priv_key) 340 { 341 if (BN_cmp(eckey->priv_key, order) >= 0) 342 { 343 ECerr(EC_F_EC_KEY_CHECK_KEY, EC_R_WRONG_ORDER); 344 goto err; 345 } 346 if (!EC_POINT_mul(eckey->group, point, eckey->priv_key, 347 NULL, NULL, ctx)) 348 { 349 ECerr(EC_F_EC_KEY_CHECK_KEY, ERR_R_EC_LIB); 350 goto err; 351 } 352 if (EC_POINT_cmp(eckey->group, point, eckey->pub_key, 353 ctx) != 0) 354 { 355 ECerr(EC_F_EC_KEY_CHECK_KEY, EC_R_INVALID_PRIVATE_KEY); 356 goto err; 357 } 358 } 359 ok = 1; 360 err: 361 if (ctx != NULL) 362 BN_CTX_free(ctx); 363 if (point != NULL) 364 EC_POINT_free(point); 365 return(ok); 366 } 367 368 const EC_GROUP *EC_KEY_get0_group(const EC_KEY *key) 369 { 370 return key->group; 371 } 372 373 int EC_KEY_set_group(EC_KEY *key, const EC_GROUP *group) 374 { 375 if (key->group != NULL) 376 EC_GROUP_free(key->group); 377 key->group = EC_GROUP_dup(group); 378 return (key->group == NULL) ? 0 : 1; 379 } 380 381 const BIGNUM *EC_KEY_get0_private_key(const EC_KEY *key) 382 { 383 return key->priv_key; 384 } 385 386 int EC_KEY_set_private_key(EC_KEY *key, const BIGNUM *priv_key) 387 { 388 if (key->priv_key) 389 BN_clear_free(key->priv_key); 390 key->priv_key = BN_dup(priv_key); 391 return (key->priv_key == NULL) ? 0 : 1; 392 } 393 394 const EC_POINT *EC_KEY_get0_public_key(const EC_KEY *key) 395 { 396 return key->pub_key; 397 } 398 399 int EC_KEY_set_public_key(EC_KEY *key, const EC_POINT *pub_key) 400 { 401 if (key->pub_key != NULL) 402 EC_POINT_free(key->pub_key); 403 key->pub_key = EC_POINT_dup(pub_key, key->group); 404 return (key->pub_key == NULL) ? 0 : 1; 405 } 406 407 unsigned int EC_KEY_get_enc_flags(const EC_KEY *key) 408 { 409 return key->enc_flag; 410 } 411 412 void EC_KEY_set_enc_flags(EC_KEY *key, unsigned int flags) 413 { 414 key->enc_flag = flags; 415 } 416 417 point_conversion_form_t EC_KEY_get_conv_form(const EC_KEY *key) 418 { 419 return key->conv_form; 420 } 421 422 void EC_KEY_set_conv_form(EC_KEY *key, point_conversion_form_t cform) 423 { 424 key->conv_form = cform; 425 if (key->group != NULL) 426 EC_GROUP_set_point_conversion_form(key->group, cform); 427 } 428 429 void *EC_KEY_get_key_method_data(EC_KEY *key, 430 void *(*dup_func)(void *), void (*free_func)(void *), void (*clear_free_func)(void *)) 431 { 432 return EC_EX_DATA_get_data(key->method_data, dup_func, free_func, clear_free_func); 433 } 434 435 void EC_KEY_insert_key_method_data(EC_KEY *key, void *data, 436 void *(*dup_func)(void *), void (*free_func)(void *), void (*clear_free_func)(void *)) 437 { 438 EC_EXTRA_DATA *ex_data; 439 CRYPTO_w_lock(CRYPTO_LOCK_EC); 440 ex_data = EC_EX_DATA_get_data(key->method_data, dup_func, free_func, clear_free_func); 441 if (ex_data == NULL) 442 EC_EX_DATA_set_data(&key->method_data, data, dup_func, free_func, clear_free_func); 443 CRYPTO_w_unlock(CRYPTO_LOCK_EC); 444 } 445 446 void EC_KEY_set_asn1_flag(EC_KEY *key, int flag) 447 { 448 if (key->group != NULL) 449 EC_GROUP_set_asn1_flag(key->group, flag); 450 } 451 452 int EC_KEY_precompute_mult(EC_KEY *key, BN_CTX *ctx) 453 { 454 if (key->group == NULL) 455 return 0; 456 return EC_GROUP_precompute_mult(key->group, ctx); 457 } 458