ec_ameth.c revision 77c6be7176c48d2ce4d5979a84876d34204eedaf
1/* Written by Dr Stephen N Henson (steve@openssl.org) for the OpenSSL 2 * project 2006. 3 */ 4/* ==================================================================== 5 * Copyright (c) 2006 The OpenSSL Project. All rights reserved. 6 * 7 * Redistribution and use in source and binary forms, with or without 8 * modification, are permitted provided that the following conditions 9 * are met: 10 * 11 * 1. Redistributions of source code must retain the above copyright 12 * notice, this list of conditions and the following disclaimer. 13 * 14 * 2. Redistributions in binary form must reproduce the above copyright 15 * notice, this list of conditions and the following disclaimer in 16 * the documentation and/or other materials provided with the 17 * distribution. 18 * 19 * 3. All advertising materials mentioning features or use of this 20 * software must display the following acknowledgment: 21 * "This product includes software developed by the OpenSSL Project 22 * for use in the OpenSSL Toolkit. (http://www.OpenSSL.org/)" 23 * 24 * 4. The names "OpenSSL Toolkit" and "OpenSSL Project" must not be used to 25 * endorse or promote products derived from this software without 26 * prior written permission. For written permission, please contact 27 * licensing@OpenSSL.org. 28 * 29 * 5. Products derived from this software may not be called "OpenSSL" 30 * nor may "OpenSSL" appear in their names without prior written 31 * permission of the OpenSSL Project. 32 * 33 * 6. Redistributions of any form whatsoever must retain the following 34 * acknowledgment: 35 * "This product includes software developed by the OpenSSL Project 36 * for use in the OpenSSL Toolkit (http://www.OpenSSL.org/)" 37 * 38 * THIS SOFTWARE IS PROVIDED BY THE OpenSSL PROJECT ``AS IS'' AND ANY 39 * EXPRESSED OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE 40 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR 41 * PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE OpenSSL PROJECT OR 42 * ITS CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, 43 * SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT 44 * NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; 45 * LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) 46 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, 47 * STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) 48 * ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED 49 * OF THE POSSIBILITY OF SUCH DAMAGE. 50 * ==================================================================== 51 * 52 * This product includes cryptographic software written by Eric Young 53 * (eay@cryptsoft.com). This product includes software written by Tim 54 * Hudson (tjh@cryptsoft.com). 55 * 56 */ 57 58#include <stdio.h> 59#include "cryptlib.h" 60#include <openssl/x509.h> 61#include <openssl/ec.h> 62#include <openssl/bn.h> 63#ifndef OPENSSL_NO_CMS 64#include <openssl/cms.h> 65#endif 66#include "asn1_locl.h" 67 68static int eckey_param2type(int *pptype, void **ppval, EC_KEY *ec_key) 69 { 70 const EC_GROUP *group; 71 int nid; 72 if (ec_key == NULL || (group = EC_KEY_get0_group(ec_key)) == NULL) 73 { 74 ECerr(EC_F_ECKEY_PARAM2TYPE, EC_R_MISSING_PARAMETERS); 75 return 0; 76 } 77 if (EC_GROUP_get_asn1_flag(group) 78 && (nid = EC_GROUP_get_curve_name(group))) 79 /* we have a 'named curve' => just set the OID */ 80 { 81 *ppval = OBJ_nid2obj(nid); 82 *pptype = V_ASN1_OBJECT; 83 } 84 else /* explicit parameters */ 85 { 86 ASN1_STRING *pstr = NULL; 87 pstr = ASN1_STRING_new(); 88 if (!pstr) 89 return 0; 90 pstr->length = i2d_ECParameters(ec_key, &pstr->data); 91 if (pstr->length <= 0) 92 { 93 ASN1_STRING_free(pstr); 94 ECerr(EC_F_ECKEY_PARAM2TYPE, ERR_R_EC_LIB); 95 return 0; 96 } 97 *ppval = pstr; 98 *pptype = V_ASN1_SEQUENCE; 99 } 100 return 1; 101 } 102 103static int eckey_pub_encode(X509_PUBKEY *pk, const EVP_PKEY *pkey) 104 { 105 EC_KEY *ec_key = pkey->pkey.ec; 106 void *pval = NULL; 107 int ptype; 108 unsigned char *penc = NULL, *p; 109 int penclen; 110 111 if (!eckey_param2type(&ptype, &pval, ec_key)) 112 { 113 ECerr(EC_F_ECKEY_PUB_ENCODE, ERR_R_EC_LIB); 114 return 0; 115 } 116 penclen = i2o_ECPublicKey(ec_key, NULL); 117 if (penclen <= 0) 118 goto err; 119 penc = OPENSSL_malloc(penclen); 120 if (!penc) 121 goto err; 122 p = penc; 123 penclen = i2o_ECPublicKey(ec_key, &p); 124 if (penclen <= 0) 125 goto err; 126 if (X509_PUBKEY_set0_param(pk, OBJ_nid2obj(EVP_PKEY_EC), 127 ptype, pval, penc, penclen)) 128 return 1; 129 err: 130 if (ptype == V_ASN1_OBJECT) 131 ASN1_OBJECT_free(pval); 132 else 133 ASN1_STRING_free(pval); 134 if (penc) 135 OPENSSL_free(penc); 136 return 0; 137 } 138 139static EC_KEY *eckey_type2param(int ptype, void *pval) 140 { 141 EC_KEY *eckey = NULL; 142 if (ptype == V_ASN1_SEQUENCE) 143 { 144 ASN1_STRING *pstr = pval; 145 const unsigned char *pm = NULL; 146 int pmlen; 147 pm = pstr->data; 148 pmlen = pstr->length; 149 if (!(eckey = d2i_ECParameters(NULL, &pm, pmlen))) 150 { 151 ECerr(EC_F_ECKEY_TYPE2PARAM, EC_R_DECODE_ERROR); 152 goto ecerr; 153 } 154 } 155 else if (ptype == V_ASN1_OBJECT) 156 { 157 ASN1_OBJECT *poid = pval; 158 EC_GROUP *group; 159 160 /* type == V_ASN1_OBJECT => the parameters are given 161 * by an asn1 OID 162 */ 163 if ((eckey = EC_KEY_new()) == NULL) 164 { 165 ECerr(EC_F_ECKEY_TYPE2PARAM, ERR_R_MALLOC_FAILURE); 166 goto ecerr; 167 } 168 group = EC_GROUP_new_by_curve_name(OBJ_obj2nid(poid)); 169 if (group == NULL) 170 goto ecerr; 171 EC_GROUP_set_asn1_flag(group, OPENSSL_EC_NAMED_CURVE); 172 if (EC_KEY_set_group(eckey, group) == 0) 173 goto ecerr; 174 EC_GROUP_free(group); 175 } 176 else 177 { 178 ECerr(EC_F_ECKEY_TYPE2PARAM, EC_R_DECODE_ERROR); 179 goto ecerr; 180 } 181 182 return eckey; 183 184 ecerr: 185 if (eckey) 186 EC_KEY_free(eckey); 187 return NULL; 188 } 189 190static int eckey_pub_decode(EVP_PKEY *pkey, X509_PUBKEY *pubkey) 191 { 192 const unsigned char *p = NULL; 193 void *pval; 194 int ptype, pklen; 195 EC_KEY *eckey = NULL; 196 X509_ALGOR *palg; 197 198 if (!X509_PUBKEY_get0_param(NULL, &p, &pklen, &palg, pubkey)) 199 return 0; 200 X509_ALGOR_get0(NULL, &ptype, &pval, palg); 201 202 eckey = eckey_type2param(ptype, pval); 203 204 if (!eckey) 205 { 206 ECerr(EC_F_ECKEY_PUB_DECODE, ERR_R_EC_LIB); 207 return 0; 208 } 209 210 /* We have parameters now set public key */ 211 if (!o2i_ECPublicKey(&eckey, &p, pklen)) 212 { 213 ECerr(EC_F_ECKEY_PUB_DECODE, EC_R_DECODE_ERROR); 214 goto ecerr; 215 } 216 217 EVP_PKEY_assign_EC_KEY(pkey, eckey); 218 return 1; 219 220 ecerr: 221 if (eckey) 222 EC_KEY_free(eckey); 223 return 0; 224 } 225 226static int eckey_pub_cmp(const EVP_PKEY *a, const EVP_PKEY *b) 227 { 228 int r; 229 const EC_GROUP *group = EC_KEY_get0_group(b->pkey.ec); 230 const EC_POINT *pa = EC_KEY_get0_public_key(a->pkey.ec), 231 *pb = EC_KEY_get0_public_key(b->pkey.ec); 232 r = EC_POINT_cmp(group, pa, pb, NULL); 233 if (r == 0) 234 return 1; 235 if (r == 1) 236 return 0; 237 return -2; 238 } 239 240static int eckey_priv_decode(EVP_PKEY *pkey, PKCS8_PRIV_KEY_INFO *p8) 241 { 242 const unsigned char *p = NULL; 243 void *pval; 244 int ptype, pklen; 245 EC_KEY *eckey = NULL; 246 X509_ALGOR *palg; 247 248 if (!PKCS8_pkey_get0(NULL, &p, &pklen, &palg, p8)) 249 return 0; 250 X509_ALGOR_get0(NULL, &ptype, &pval, palg); 251 252 eckey = eckey_type2param(ptype, pval); 253 254 if (!eckey) 255 goto ecliberr; 256 257 /* We have parameters now set private key */ 258 if (!d2i_ECPrivateKey(&eckey, &p, pklen)) 259 { 260 ECerr(EC_F_ECKEY_PRIV_DECODE, EC_R_DECODE_ERROR); 261 goto ecerr; 262 } 263 264 /* calculate public key (if necessary) */ 265 if (EC_KEY_get0_public_key(eckey) == NULL) 266 { 267 const BIGNUM *priv_key; 268 const EC_GROUP *group; 269 EC_POINT *pub_key; 270 /* the public key was not included in the SEC1 private 271 * key => calculate the public key */ 272 group = EC_KEY_get0_group(eckey); 273 pub_key = EC_POINT_new(group); 274 if (pub_key == NULL) 275 { 276 ECerr(EC_F_ECKEY_PRIV_DECODE, ERR_R_EC_LIB); 277 goto ecliberr; 278 } 279 if (!EC_POINT_copy(pub_key, EC_GROUP_get0_generator(group))) 280 { 281 EC_POINT_free(pub_key); 282 ECerr(EC_F_ECKEY_PRIV_DECODE, ERR_R_EC_LIB); 283 goto ecliberr; 284 } 285 priv_key = EC_KEY_get0_private_key(eckey); 286 if (!EC_POINT_mul(group, pub_key, priv_key, NULL, NULL, NULL)) 287 { 288 EC_POINT_free(pub_key); 289 ECerr(EC_F_ECKEY_PRIV_DECODE, ERR_R_EC_LIB); 290 goto ecliberr; 291 } 292 if (EC_KEY_set_public_key(eckey, pub_key) == 0) 293 { 294 EC_POINT_free(pub_key); 295 ECerr(EC_F_ECKEY_PRIV_DECODE, ERR_R_EC_LIB); 296 goto ecliberr; 297 } 298 EC_POINT_free(pub_key); 299 } 300 301 EVP_PKEY_assign_EC_KEY(pkey, eckey); 302 return 1; 303 304 ecliberr: 305 ECerr(EC_F_ECKEY_PRIV_DECODE, ERR_R_EC_LIB); 306 ecerr: 307 if (eckey) 308 EC_KEY_free(eckey); 309 return 0; 310 } 311 312static int eckey_priv_encode(PKCS8_PRIV_KEY_INFO *p8, const EVP_PKEY *pkey) 313{ 314 EC_KEY *ec_key; 315 unsigned char *ep, *p; 316 int eplen, ptype; 317 void *pval; 318 unsigned int tmp_flags, old_flags; 319 320 ec_key = pkey->pkey.ec; 321 322 if (!eckey_param2type(&ptype, &pval, ec_key)) 323 { 324 ECerr(EC_F_ECKEY_PRIV_ENCODE, EC_R_DECODE_ERROR); 325 return 0; 326 } 327 328 /* set the private key */ 329 330 /* do not include the parameters in the SEC1 private key 331 * see PKCS#11 12.11 */ 332 old_flags = EC_KEY_get_enc_flags(ec_key); 333 tmp_flags = old_flags | EC_PKEY_NO_PARAMETERS; 334 EC_KEY_set_enc_flags(ec_key, tmp_flags); 335 eplen = i2d_ECPrivateKey(ec_key, NULL); 336 if (!eplen) 337 { 338 EC_KEY_set_enc_flags(ec_key, old_flags); 339 ECerr(EC_F_ECKEY_PRIV_ENCODE, ERR_R_EC_LIB); 340 return 0; 341 } 342 ep = (unsigned char *) OPENSSL_malloc(eplen); 343 if (!ep) 344 { 345 EC_KEY_set_enc_flags(ec_key, old_flags); 346 ECerr(EC_F_ECKEY_PRIV_ENCODE, ERR_R_MALLOC_FAILURE); 347 return 0; 348 } 349 p = ep; 350 if (!i2d_ECPrivateKey(ec_key, &p)) 351 { 352 EC_KEY_set_enc_flags(ec_key, old_flags); 353 OPENSSL_free(ep); 354 ECerr(EC_F_ECKEY_PRIV_ENCODE, ERR_R_EC_LIB); 355 return 0; 356 } 357 /* restore old encoding flags */ 358 EC_KEY_set_enc_flags(ec_key, old_flags); 359 360 if (!PKCS8_pkey_set0(p8, OBJ_nid2obj(NID_X9_62_id_ecPublicKey), 0, 361 ptype, pval, ep, eplen)) 362 return 0; 363 364 return 1; 365} 366 367static int int_ec_size(const EVP_PKEY *pkey) 368 { 369 return ECDSA_size(pkey->pkey.ec); 370 } 371 372static int ec_bits(const EVP_PKEY *pkey) 373 { 374 BIGNUM *order = BN_new(); 375 const EC_GROUP *group; 376 int ret; 377 378 if (!order) 379 { 380 ERR_clear_error(); 381 return 0; 382 } 383 group = EC_KEY_get0_group(pkey->pkey.ec); 384 if (!EC_GROUP_get_order(group, order, NULL)) 385 { 386 ERR_clear_error(); 387 return 0; 388 } 389 390 ret = BN_num_bits(order); 391 BN_free(order); 392 return ret; 393 } 394 395static int ec_missing_parameters(const EVP_PKEY *pkey) 396 { 397 if (EC_KEY_get0_group(pkey->pkey.ec) == NULL) 398 return 1; 399 return 0; 400 } 401 402static int ec_copy_parameters(EVP_PKEY *to, const EVP_PKEY *from) 403 { 404 EC_GROUP *group = EC_GROUP_dup(EC_KEY_get0_group(from->pkey.ec)); 405 if (group == NULL) 406 return 0; 407 if (EC_KEY_set_group(to->pkey.ec, group) == 0) 408 return 0; 409 EC_GROUP_free(group); 410 return 1; 411 } 412 413static int ec_cmp_parameters(const EVP_PKEY *a, const EVP_PKEY *b) 414 { 415 const EC_GROUP *group_a = EC_KEY_get0_group(a->pkey.ec), 416 *group_b = EC_KEY_get0_group(b->pkey.ec); 417 if (EC_GROUP_cmp(group_a, group_b, NULL)) 418 return 0; 419 else 420 return 1; 421 } 422 423static void int_ec_free(EVP_PKEY *pkey) 424 { 425 EC_KEY_free(pkey->pkey.ec); 426 } 427 428static int do_EC_KEY_print(BIO *bp, const EC_KEY *x, int off, int ktype) 429 { 430 unsigned char *buffer=NULL; 431 const char *ecstr; 432 size_t buf_len=0, i; 433 int ret=0, reason=ERR_R_BIO_LIB; 434 BIGNUM *pub_key=NULL, *order=NULL; 435 BN_CTX *ctx=NULL; 436 const EC_GROUP *group; 437 const EC_POINT *public_key; 438 const BIGNUM *priv_key; 439 440 if (x == NULL || (group = EC_KEY_get0_group(x)) == NULL) 441 { 442 reason = ERR_R_PASSED_NULL_PARAMETER; 443 goto err; 444 } 445 446 ctx = BN_CTX_new(); 447 if (ctx == NULL) 448 { 449 reason = ERR_R_MALLOC_FAILURE; 450 goto err; 451 } 452 453 if (ktype > 0) 454 { 455 public_key = EC_KEY_get0_public_key(x); 456 if ((pub_key = EC_POINT_point2bn(group, public_key, 457 EC_KEY_get_conv_form(x), NULL, ctx)) == NULL) 458 { 459 reason = ERR_R_EC_LIB; 460 goto err; 461 } 462 if (pub_key) 463 buf_len = (size_t)BN_num_bytes(pub_key); 464 } 465 466 if (ktype == 2) 467 { 468 priv_key = EC_KEY_get0_private_key(x); 469 if (priv_key && (i = (size_t)BN_num_bytes(priv_key)) > buf_len) 470 buf_len = i; 471 } 472 else 473 priv_key = NULL; 474 475 if (ktype > 0) 476 { 477 buf_len += 10; 478 if ((buffer = OPENSSL_malloc(buf_len)) == NULL) 479 { 480 reason = ERR_R_MALLOC_FAILURE; 481 goto err; 482 } 483 } 484 if (ktype == 2) 485 ecstr = "Private-Key"; 486 else if (ktype == 1) 487 ecstr = "Public-Key"; 488 else 489 ecstr = "ECDSA-Parameters"; 490 491 if (!BIO_indent(bp, off, 128)) 492 goto err; 493 if ((order = BN_new()) == NULL) 494 goto err; 495 if (!EC_GROUP_get_order(group, order, NULL)) 496 goto err; 497 if (BIO_printf(bp, "%s: (%d bit)\n", ecstr, 498 BN_num_bits(order)) <= 0) goto err; 499 500 if ((priv_key != NULL) && !ASN1_bn_print(bp, "priv:", priv_key, 501 buffer, off)) 502 goto err; 503 if ((pub_key != NULL) && !ASN1_bn_print(bp, "pub: ", pub_key, 504 buffer, off)) 505 goto err; 506 if (!ECPKParameters_print(bp, group, off)) 507 goto err; 508 ret=1; 509err: 510 if (!ret) 511 ECerr(EC_F_DO_EC_KEY_PRINT, reason); 512 if (pub_key) 513 BN_free(pub_key); 514 if (order) 515 BN_free(order); 516 if (ctx) 517 BN_CTX_free(ctx); 518 if (buffer != NULL) 519 OPENSSL_free(buffer); 520 return(ret); 521 } 522 523static int eckey_param_decode(EVP_PKEY *pkey, 524 const unsigned char **pder, int derlen) 525 { 526 EC_KEY *eckey; 527 if (!(eckey = d2i_ECParameters(NULL, pder, derlen))) 528 { 529 ECerr(EC_F_ECKEY_PARAM_DECODE, ERR_R_EC_LIB); 530 return 0; 531 } 532 EVP_PKEY_assign_EC_KEY(pkey, eckey); 533 return 1; 534 } 535 536static int eckey_param_encode(const EVP_PKEY *pkey, unsigned char **pder) 537 { 538 return i2d_ECParameters(pkey->pkey.ec, pder); 539 } 540 541static int eckey_param_print(BIO *bp, const EVP_PKEY *pkey, int indent, 542 ASN1_PCTX *ctx) 543 { 544 return do_EC_KEY_print(bp, pkey->pkey.ec, indent, 0); 545 } 546 547static int eckey_pub_print(BIO *bp, const EVP_PKEY *pkey, int indent, 548 ASN1_PCTX *ctx) 549 { 550 return do_EC_KEY_print(bp, pkey->pkey.ec, indent, 1); 551 } 552 553 554static int eckey_priv_print(BIO *bp, const EVP_PKEY *pkey, int indent, 555 ASN1_PCTX *ctx) 556 { 557 return do_EC_KEY_print(bp, pkey->pkey.ec, indent, 2); 558 } 559 560static int old_ec_priv_decode(EVP_PKEY *pkey, 561 const unsigned char **pder, int derlen) 562 { 563 EC_KEY *ec; 564 if (!(ec = d2i_ECPrivateKey (NULL, pder, derlen))) 565 { 566 ECerr(EC_F_OLD_EC_PRIV_DECODE, EC_R_DECODE_ERROR); 567 return 0; 568 } 569 EVP_PKEY_assign_EC_KEY(pkey, ec); 570 return 1; 571 } 572 573static int old_ec_priv_encode(const EVP_PKEY *pkey, unsigned char **pder) 574 { 575 return i2d_ECPrivateKey(pkey->pkey.ec, pder); 576 } 577 578static int ec_pkey_ctrl(EVP_PKEY *pkey, int op, long arg1, void *arg2) 579 { 580 switch (op) 581 { 582 case ASN1_PKEY_CTRL_PKCS7_SIGN: 583 if (arg1 == 0) 584 { 585 int snid, hnid; 586 X509_ALGOR *alg1, *alg2; 587 PKCS7_SIGNER_INFO_get0_algs(arg2, NULL, &alg1, &alg2); 588 if (alg1 == NULL || alg1->algorithm == NULL) 589 return -1; 590 hnid = OBJ_obj2nid(alg1->algorithm); 591 if (hnid == NID_undef) 592 return -1; 593 if (!OBJ_find_sigid_by_algs(&snid, hnid, EVP_PKEY_id(pkey))) 594 return -1; 595 X509_ALGOR_set0(alg2, OBJ_nid2obj(snid), V_ASN1_UNDEF, 0); 596 } 597 return 1; 598#ifndef OPENSSL_NO_CMS 599 case ASN1_PKEY_CTRL_CMS_SIGN: 600 if (arg1 == 0) 601 { 602 int snid, hnid; 603 X509_ALGOR *alg1, *alg2; 604 CMS_SignerInfo_get0_algs(arg2, NULL, NULL, 605 &alg1, &alg2); 606 if (alg1 == NULL || alg1->algorithm == NULL) 607 return -1; 608 hnid = OBJ_obj2nid(alg1->algorithm); 609 if (hnid == NID_undef) 610 return -1; 611 if (!OBJ_find_sigid_by_algs(&snid, hnid, EVP_PKEY_id(pkey))) 612 return -1; 613 X509_ALGOR_set0(alg2, OBJ_nid2obj(snid), V_ASN1_UNDEF, 0); 614 } 615 return 1; 616#endif 617 618 case ASN1_PKEY_CTRL_DEFAULT_MD_NID: 619 *(int *)arg2 = NID_sha1; 620 return 2; 621 622 default: 623 return -2; 624 625 } 626 627 } 628 629const EVP_PKEY_ASN1_METHOD eckey_asn1_meth = 630 { 631 EVP_PKEY_EC, 632 EVP_PKEY_EC, 633 0, 634 "EC", 635 "OpenSSL EC algorithm", 636 637 eckey_pub_decode, 638 eckey_pub_encode, 639 eckey_pub_cmp, 640 eckey_pub_print, 641 642 eckey_priv_decode, 643 eckey_priv_encode, 644 eckey_priv_print, 645 646 int_ec_size, 647 ec_bits, 648 649 eckey_param_decode, 650 eckey_param_encode, 651 ec_missing_parameters, 652 ec_copy_parameters, 653 ec_cmp_parameters, 654 eckey_param_print, 655 0, 656 657 int_ec_free, 658 ec_pkey_ctrl, 659 old_ec_priv_decode, 660 old_ec_priv_encode 661 }; 662