ec_ameth.c revision ff41a4bc41ae1e1391f9b05117623ff70b985983
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 } 356 /* restore old encoding flags */ 357 EC_KEY_set_enc_flags(ec_key, old_flags); 358 359 if (!PKCS8_pkey_set0(p8, OBJ_nid2obj(NID_X9_62_id_ecPublicKey), 0, 360 ptype, pval, ep, eplen)) 361 return 0; 362 363 return 1; 364} 365 366static int int_ec_size(const EVP_PKEY *pkey) 367 { 368 return ECDSA_size(pkey->pkey.ec); 369 } 370 371static int ec_bits(const EVP_PKEY *pkey) 372 { 373 BIGNUM *order = BN_new(); 374 const EC_GROUP *group; 375 int ret; 376 377 if (!order) 378 { 379 ERR_clear_error(); 380 return 0; 381 } 382 group = EC_KEY_get0_group(pkey->pkey.ec); 383 if (!EC_GROUP_get_order(group, order, NULL)) 384 { 385 ERR_clear_error(); 386 return 0; 387 } 388 389 ret = BN_num_bits(order); 390 BN_free(order); 391 return ret; 392 } 393 394static int ec_missing_parameters(const EVP_PKEY *pkey) 395 { 396 if (EC_KEY_get0_group(pkey->pkey.ec) == NULL) 397 return 1; 398 return 0; 399 } 400 401static int ec_copy_parameters(EVP_PKEY *to, const EVP_PKEY *from) 402 { 403 EC_GROUP *group = EC_GROUP_dup(EC_KEY_get0_group(from->pkey.ec)); 404 if (group == NULL) 405 return 0; 406 if (EC_KEY_set_group(to->pkey.ec, group) == 0) 407 return 0; 408 EC_GROUP_free(group); 409 return 1; 410 } 411 412static int ec_cmp_parameters(const EVP_PKEY *a, const EVP_PKEY *b) 413 { 414 const EC_GROUP *group_a = EC_KEY_get0_group(a->pkey.ec), 415 *group_b = EC_KEY_get0_group(b->pkey.ec); 416 if (EC_GROUP_cmp(group_a, group_b, NULL)) 417 return 0; 418 else 419 return 1; 420 } 421 422static void int_ec_free(EVP_PKEY *pkey) 423 { 424 EC_KEY_free(pkey->pkey.ec); 425 } 426 427static int do_EC_KEY_print(BIO *bp, const EC_KEY *x, int off, int ktype) 428 { 429 unsigned char *buffer=NULL; 430 const char *ecstr; 431 size_t buf_len=0, i; 432 int ret=0, reason=ERR_R_BIO_LIB; 433 BIGNUM *pub_key=NULL, *order=NULL; 434 BN_CTX *ctx=NULL; 435 const EC_GROUP *group; 436 const EC_POINT *public_key; 437 const BIGNUM *priv_key; 438 439 if (x == NULL || (group = EC_KEY_get0_group(x)) == NULL) 440 { 441 reason = ERR_R_PASSED_NULL_PARAMETER; 442 goto err; 443 } 444 445 ctx = BN_CTX_new(); 446 if (ctx == NULL) 447 { 448 reason = ERR_R_MALLOC_FAILURE; 449 goto err; 450 } 451 452 if (ktype > 0) 453 { 454 public_key = EC_KEY_get0_public_key(x); 455 if ((pub_key = EC_POINT_point2bn(group, public_key, 456 EC_KEY_get_conv_form(x), NULL, ctx)) == NULL) 457 { 458 reason = ERR_R_EC_LIB; 459 goto err; 460 } 461 if (pub_key) 462 buf_len = (size_t)BN_num_bytes(pub_key); 463 } 464 465 if (ktype == 2) 466 { 467 priv_key = EC_KEY_get0_private_key(x); 468 if (priv_key && (i = (size_t)BN_num_bytes(priv_key)) > buf_len) 469 buf_len = i; 470 } 471 else 472 priv_key = NULL; 473 474 if (ktype > 0) 475 { 476 buf_len += 10; 477 if ((buffer = OPENSSL_malloc(buf_len)) == NULL) 478 { 479 reason = ERR_R_MALLOC_FAILURE; 480 goto err; 481 } 482 } 483 if (ktype == 2) 484 ecstr = "Private-Key"; 485 else if (ktype == 1) 486 ecstr = "Public-Key"; 487 else 488 ecstr = "ECDSA-Parameters"; 489 490 if (!BIO_indent(bp, off, 128)) 491 goto err; 492 if ((order = BN_new()) == NULL) 493 goto err; 494 if (!EC_GROUP_get_order(group, order, NULL)) 495 goto err; 496 if (BIO_printf(bp, "%s: (%d bit)\n", ecstr, 497 BN_num_bits(order)) <= 0) goto err; 498 499 if ((priv_key != NULL) && !ASN1_bn_print(bp, "priv:", priv_key, 500 buffer, off)) 501 goto err; 502 if ((pub_key != NULL) && !ASN1_bn_print(bp, "pub: ", pub_key, 503 buffer, off)) 504 goto err; 505 if (!ECPKParameters_print(bp, group, off)) 506 goto err; 507 ret=1; 508err: 509 if (!ret) 510 ECerr(EC_F_DO_EC_KEY_PRINT, reason); 511 if (pub_key) 512 BN_free(pub_key); 513 if (order) 514 BN_free(order); 515 if (ctx) 516 BN_CTX_free(ctx); 517 if (buffer != NULL) 518 OPENSSL_free(buffer); 519 return(ret); 520 } 521 522static int eckey_param_decode(EVP_PKEY *pkey, 523 const unsigned char **pder, int derlen) 524 { 525 EC_KEY *eckey; 526 if (!(eckey = d2i_ECParameters(NULL, pder, derlen))) 527 { 528 ECerr(EC_F_ECKEY_PARAM_DECODE, ERR_R_EC_LIB); 529 return 0; 530 } 531 EVP_PKEY_assign_EC_KEY(pkey, eckey); 532 return 1; 533 } 534 535static int eckey_param_encode(const EVP_PKEY *pkey, unsigned char **pder) 536 { 537 return i2d_ECParameters(pkey->pkey.ec, pder); 538 } 539 540static int eckey_param_print(BIO *bp, const EVP_PKEY *pkey, int indent, 541 ASN1_PCTX *ctx) 542 { 543 return do_EC_KEY_print(bp, pkey->pkey.ec, indent, 0); 544 } 545 546static int eckey_pub_print(BIO *bp, const EVP_PKEY *pkey, int indent, 547 ASN1_PCTX *ctx) 548 { 549 return do_EC_KEY_print(bp, pkey->pkey.ec, indent, 1); 550 } 551 552 553static int eckey_priv_print(BIO *bp, const EVP_PKEY *pkey, int indent, 554 ASN1_PCTX *ctx) 555 { 556 return do_EC_KEY_print(bp, pkey->pkey.ec, indent, 2); 557 } 558 559static int old_ec_priv_decode(EVP_PKEY *pkey, 560 const unsigned char **pder, int derlen) 561 { 562 EC_KEY *ec; 563 if (!(ec = d2i_ECPrivateKey (NULL, pder, derlen))) 564 { 565 ECerr(EC_F_OLD_EC_PRIV_DECODE, EC_R_DECODE_ERROR); 566 return 0; 567 } 568 EVP_PKEY_assign_EC_KEY(pkey, ec); 569 return 1; 570 } 571 572static int old_ec_priv_encode(const EVP_PKEY *pkey, unsigned char **pder) 573 { 574 return i2d_ECPrivateKey(pkey->pkey.ec, pder); 575 } 576 577static int ec_pkey_ctrl(EVP_PKEY *pkey, int op, long arg1, void *arg2) 578 { 579 switch (op) 580 { 581 case ASN1_PKEY_CTRL_PKCS7_SIGN: 582 if (arg1 == 0) 583 { 584 int snid, hnid; 585 X509_ALGOR *alg1, *alg2; 586 PKCS7_SIGNER_INFO_get0_algs(arg2, NULL, &alg1, &alg2); 587 if (alg1 == NULL || alg1->algorithm == NULL) 588 return -1; 589 hnid = OBJ_obj2nid(alg1->algorithm); 590 if (hnid == NID_undef) 591 return -1; 592 if (!OBJ_find_sigid_by_algs(&snid, hnid, EVP_PKEY_id(pkey))) 593 return -1; 594 X509_ALGOR_set0(alg2, OBJ_nid2obj(snid), V_ASN1_UNDEF, 0); 595 } 596 return 1; 597#ifndef OPENSSL_NO_CMS 598 case ASN1_PKEY_CTRL_CMS_SIGN: 599 if (arg1 == 0) 600 { 601 int snid, hnid; 602 X509_ALGOR *alg1, *alg2; 603 CMS_SignerInfo_get0_algs(arg2, NULL, NULL, 604 &alg1, &alg2); 605 if (alg1 == NULL || alg1->algorithm == NULL) 606 return -1; 607 hnid = OBJ_obj2nid(alg1->algorithm); 608 if (hnid == NID_undef) 609 return -1; 610 if (!OBJ_find_sigid_by_algs(&snid, hnid, EVP_PKEY_id(pkey))) 611 return -1; 612 X509_ALGOR_set0(alg2, OBJ_nid2obj(snid), V_ASN1_UNDEF, 0); 613 } 614 return 1; 615#endif 616 617 case ASN1_PKEY_CTRL_DEFAULT_MD_NID: 618 *(int *)arg2 = NID_sha1; 619 return 2; 620 621 default: 622 return -2; 623 624 } 625 626 } 627 628const EVP_PKEY_ASN1_METHOD eckey_asn1_meth = 629 { 630 EVP_PKEY_EC, 631 EVP_PKEY_EC, 632 0, 633 "EC", 634 "OpenSSL EC algorithm", 635 636 eckey_pub_decode, 637 eckey_pub_encode, 638 eckey_pub_cmp, 639 eckey_pub_print, 640 641 eckey_priv_decode, 642 eckey_priv_encode, 643 eckey_priv_print, 644 645 int_ec_size, 646 ec_bits, 647 648 eckey_param_decode, 649 eckey_param_encode, 650 ec_missing_parameters, 651 ec_copy_parameters, 652 ec_cmp_parameters, 653 eckey_param_print, 654 0, 655 656 int_ec_free, 657 ec_pkey_ctrl, 658 old_ec_priv_decode, 659 old_ec_priv_encode 660 }; 661