crypto/ec/ec_lib.c

   1 /* crypto/ec/ec_lib.c */
   2 /*
   3  * Originally written by Bodo Moeller for the OpenSSL project.
   4  */
   5 /* ====================================================================
   6  * Copyright (c) 1998-2003 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  * Binary polynomial ECC support in OpenSSL originally developed by
  61  * SUN MICROSYSTEMS, INC., and contributed to the OpenSSL project.
  62  */
  63
  64 #include <string.h>
  65
  66 #include <openssl/err.h>
  67 #include <openssl/opensslv.h>
  68
  69 #include "ec_lcl.h"
  70
  71 const char EC_version[] = "EC" OPENSSL_VERSION_PTEXT;
  72
  73 /* functions for EC_GROUP objects */
  74
  75 EC_GROUP *EC_GROUP_new(const EC_METHOD *meth)
  76 {
  77     EC_GROUP *ret;
  78
  79     if (meth == NULL) {
  80         ECerr(EC_F_EC_GROUP_NEW, EC_R_SLOT_FULL);
  81         return NULL;
  82     }
  83     if (meth->group_init == 0) {
  84         ECerr(EC_F_EC_GROUP_NEW, ERR_R_SHOULD_NOT_HAVE_BEEN_CALLED);
  85         return NULL;
  86     }
  87
  88     ret = OPENSSL_malloc(sizeof *ret);
  89     if (ret == NULL) {
  90         ECerr(EC_F_EC_GROUP_NEW, ERR_R_MALLOC_FAILURE);
  91         return NULL;
  92     }
  93
  94     ret->meth = meth;
  95
  96     ret->extra_data = NULL;
  97     ret->mont_data = NULL;
  98
  99     ret->generator = NULL;
 100     ret->order = BN_new();
 101     ret->cofactor = NULL;
 102     if (!ret->order)
 103         goto err;
 104     ret->cofactor = BN_new();
 105     if (!ret->cofactor)
 106         goto err;
 107
 108     ret->curve_name = 0;
 109     ret->asn1_flag = OPENSSL_EC_NAMED_CURVE;
 110     ret->asn1_form = POINT_CONVERSION_UNCOMPRESSED;
 111
 112     ret->seed = NULL;
 113     ret->seed_len = 0;
 114
 115     if (!meth->group_init(ret))
 116         goto err;
 117
 118     return ret;
 119  err:
 120     BN_free(ret->order);
 121     BN_free(ret->cofactor);
 122     OPENSSL_free(ret);
 123     return NULL;
 124 }
 125
 126 void EC_GROUP_free(EC_GROUP *group)
 127 {
 128     if (!group)
 129         return;
 130
 131     if (group->meth->group_finish != 0)
 132         group->meth->group_finish(group);
 133
 134     EC_EX_DATA_free_all_data(&group->extra_data);
 135
 136     BN_MONT_CTX_free(group->mont_data);
 137
 138     EC_POINT_free(group->generator);
 139     BN_free(group->order);
 140     BN_free(group->cofactor);
 141
 142     if (group->seed)
 143         OPENSSL_free(group->seed);
 144
 145     OPENSSL_free(group);
 146 }
 147
 148 void EC_GROUP_clear_free(EC_GROUP *group)
 149 {
 150     if (!group)
 151         return;
 152
 153     if (group->meth->group_clear_finish != 0)
 154         group->meth->group_clear_finish(group);
 155     else if (group->meth->group_finish != 0)
 156         group->meth->group_finish(group);
 157
 158     EC_EX_DATA_clear_free_all_data(&group->extra_data);
 159
 160     BN_MONT_CTX_free(group->mont_data);
 161
 162     EC_POINT_clear_free(group->generator);
 163     BN_clear_free(group->order);
 164     BN_clear_free(group->cofactor);
 165     OPENSSL_clear_free(group->seed, group->seed_len);
 166     OPENSSL_clear_free(group, sizeof *group);
 167 }
 168
 169 int EC_GROUP_copy(EC_GROUP *dest, const EC_GROUP *src)
 170 {
 171     EC_EXTRA_DATA *d;
 172
 173     if (dest->meth->group_copy == 0) {
 174         ECerr(EC_F_EC_GROUP_COPY, ERR_R_SHOULD_NOT_HAVE_BEEN_CALLED);
 175         return 0;
 176     }
 177     if (dest->meth != src->meth) {
 178         ECerr(EC_F_EC_GROUP_COPY, EC_R_INCOMPATIBLE_OBJECTS);
 179         return 0;
 180     }
 181     if (dest == src)
 182         return 1;
 183
 184     EC_EX_DATA_free_all_data(&dest->extra_data);
 185
 186     for (d = src->extra_data; d != NULL; d = d->next) {
 187         void *t = d->dup_func(d->data);
 188
 189         if (t == NULL)
 190             return 0;
 191         if (!EC_EX_DATA_set_data
 192             (&dest->extra_data, t, d->dup_func, d->free_func,
 193              d->clear_free_func))
 194             return 0;
 195     }
 196
 197     if (src->mont_data != NULL) {
 198         if (dest->mont_data == NULL) {
 199             dest->mont_data = BN_MONT_CTX_new();
 200             if (dest->mont_data == NULL)
 201                 return 0;
 202         }
 203         if (!BN_MONT_CTX_copy(dest->mont_data, src->mont_data))
 204             return 0;
 205     } else {
 206         /* src->generator == NULL */
 207         BN_MONT_CTX_free(dest->mont_data);
 208         dest->mont_data = NULL;
 209     }
 210
 211     if (src->generator != NULL) {
 212         if (dest->generator == NULL) {
 213             dest->generator = EC_POINT_new(dest);
 214             if (dest->generator == NULL)
 215                 return 0;
 216         }
 217         if (!EC_POINT_copy(dest->generator, src->generator))
 218             return 0;
 219     } else {
 220         /* src->generator == NULL */
 221         EC_POINT_clear_free(dest->generator);
 222         dest->generator = NULL;
 223     }
 224
 225     if (!BN_copy(dest->order, src->order))
 226         return 0;
 227     if (!BN_copy(dest->cofactor, src->cofactor))
 228         return 0;
 229
 230     dest->curve_name = src->curve_name;
 231     dest->asn1_flag = src->asn1_flag;
 232     dest->asn1_form = src->asn1_form;
 233
 234     if (src->seed) {
 235         if (dest->seed)
 236             OPENSSL_free(dest->seed);
 237         dest->seed = OPENSSL_malloc(src->seed_len);
 238         if (dest->seed == NULL)
 239             return 0;
 240         if (!memcpy(dest->seed, src->seed, src->seed_len))
 241             return 0;
 242         dest->seed_len = src->seed_len;
 243     } else {
 244         if (dest->seed)
 245             OPENSSL_free(dest->seed);
 246         dest->seed = NULL;
 247         dest->seed_len = 0;
 248     }
 249
 250     return dest->meth->group_copy(dest, src);
 251 }
 252
 253 EC_GROUP *EC_GROUP_dup(const EC_GROUP *a)
 254 {
 255     EC_GROUP *t = NULL;
 256     int ok = 0;
 257
 258     if (a == NULL)
 259         return NULL;
 260
 261     if ((t = EC_GROUP_new(a->meth)) == NULL)
 262         return (NULL);
 263     if (!EC_GROUP_copy(t, a))
 264         goto err;
 265
 266     ok = 1;
 267
 268  err:
 269     if (!ok) {
 270         EC_GROUP_free(t);
 271         return NULL;
 272     }
 273         return t;
 274 }
 275
 276 const EC_METHOD *EC_GROUP_method_of(const EC_GROUP *group)
 277 {
 278     return group->meth;
 279 }
 280
 281 int EC_METHOD_get_field_type(const EC_METHOD *meth)
 282 {
 283     return meth->field_type;
 284 }
 285
 286 int EC_GROUP_set_generator(EC_GROUP *group, const EC_POINT *generator,
 287                            const BIGNUM *order, const BIGNUM *cofactor)
 288 {
 289     if (generator == NULL) {
 290         ECerr(EC_F_EC_GROUP_SET_GENERATOR, ERR_R_PASSED_NULL_PARAMETER);
 291         return 0;
 292     }
 293
 294     if (group->generator == NULL) {
 295         group->generator = EC_POINT_new(group);
 296         if (group->generator == NULL)
 297             return 0;
 298     }
 299     if (!EC_POINT_copy(group->generator, generator))
 300         return 0;
 301
 302     if (order != NULL) {
 303         if (!BN_copy(group->order, order))
 304             return 0;
 305     } else
 306         BN_zero(group->order);
 307
 308     if (cofactor != NULL) {
 309         if (!BN_copy(group->cofactor, cofactor))
 310             return 0;
 311     } else
 312         BN_zero(group->cofactor);
 313
 314     /*
 315      * We ignore the return value because some groups have an order with
 316      * factors of two, which makes the Montgomery setup fail.
 317      * |group->mont_data| will be NULL in this case.
 318      */
 319     ec_precompute_mont_data(group);
 320
 321     return 1;
 322 }
 323
 324 const EC_POINT *EC_GROUP_get0_generator(const EC_GROUP *group)
 325 {
 326     return group->generator;
 327 }
 328
 329 BN_MONT_CTX *EC_GROUP_get_mont_data(const EC_GROUP *group)
 330 {
 331     return group->mont_data;
 332 }
 333
 334 int EC_GROUP_get_order(const EC_GROUP *group, BIGNUM *order, BN_CTX *ctx)
 335 {
 336     if (!BN_copy(order, group->order))
 337         return 0;
 338
 339     return !BN_is_zero(order);
 340 }
 341
 342 int EC_GROUP_get_cofactor(const EC_GROUP *group, BIGNUM *cofactor,
 343                           BN_CTX *ctx)
 344 {
 345     if (!BN_copy(cofactor, group->cofactor))
 346         return 0;
 347
 348     return !BN_is_zero(group->cofactor);
 349 }
 350
 351 void EC_GROUP_set_curve_name(EC_GROUP *group, int nid)
 352 {
 353     group->curve_name = nid;
 354 }
 355
 356 int EC_GROUP_get_curve_name(const EC_GROUP *group)
 357 {
 358     return group->curve_name;
 359 }
 360
 361 void EC_GROUP_set_asn1_flag(EC_GROUP *group, int flag)
 362 {
 363     group->asn1_flag = flag;
 364 }
 365
 366 int EC_GROUP_get_asn1_flag(const EC_GROUP *group)
 367 {
 368     return group->asn1_flag;
 369 }
 370
 371 void EC_GROUP_set_point_conversion_form(EC_GROUP *group,
 372                                         point_conversion_form_t form)
 373 {
 374     group->asn1_form = form;
 375 }
 376
 377 point_conversion_form_t EC_GROUP_get_point_conversion_form(const EC_GROUP
 378                                                            *group)
 379 {
 380     return group->asn1_form;
 381 }
 382
 383 size_t EC_GROUP_set_seed(EC_GROUP *group, const unsigned char *p, size_t len)
 384 {
 385     if (group->seed) {
 386         OPENSSL_free(group->seed);
 387         group->seed = NULL;
 388         group->seed_len = 0;
 389     }
 390
 391     if (!len || !p)
 392         return 1;
 393
 394     if ((group->seed = OPENSSL_malloc(len)) == NULL)
 395         return 0;
 396     memcpy(group->seed, p, len);
 397     group->seed_len = len;
 398
 399     return len;
 400 }
 401
 402 unsigned char *EC_GROUP_get0_seed(const EC_GROUP *group)
 403 {
 404     return group->seed;
 405 }
 406
 407 size_t EC_GROUP_get_seed_len(const EC_GROUP *group)
 408 {
 409     return group->seed_len;
 410 }
 411
 412 int EC_GROUP_set_curve_GFp(EC_GROUP *group, const BIGNUM *p, const BIGNUM *a,
 413                            const BIGNUM *b, BN_CTX *ctx)
 414 {
 415     if (group->meth->group_set_curve == 0) {
 416         ECerr(EC_F_EC_GROUP_SET_CURVE_GFP, ERR_R_SHOULD_NOT_HAVE_BEEN_CALLED);
 417         return 0;
 418     }
 419     return group->meth->group_set_curve(group, p, a, b, ctx);
 420 }
 421
 422 int EC_GROUP_get_curve_GFp(const EC_GROUP *group, BIGNUM *p, BIGNUM *a,
 423                            BIGNUM *b, BN_CTX *ctx)
 424 {
 425     if (group->meth->group_get_curve == 0) {
 426         ECerr(EC_F_EC_GROUP_GET_CURVE_GFP, ERR_R_SHOULD_NOT_HAVE_BEEN_CALLED);
 427         return 0;
 428     }
 429     return group->meth->group_get_curve(group, p, a, b, ctx);
 430 }
 431
 432 #ifndef OPENSSL_NO_EC2M
 433 int EC_GROUP_set_curve_GF2m(EC_GROUP *group, const BIGNUM *p, const BIGNUM *a,
 434                             const BIGNUM *b, BN_CTX *ctx)
 435 {
 436     if (group->meth->group_set_curve == 0) {
 437         ECerr(EC_F_EC_GROUP_SET_CURVE_GF2M,
 438               ERR_R_SHOULD_NOT_HAVE_BEEN_CALLED);
 439         return 0;
 440     }
 441     return group->meth->group_set_curve(group, p, a, b, ctx);
 442 }
 443
 444 int EC_GROUP_get_curve_GF2m(const EC_GROUP *group, BIGNUM *p, BIGNUM *a,
 445                             BIGNUM *b, BN_CTX *ctx)
 446 {
 447     if (group->meth->group_get_curve == 0) {
 448         ECerr(EC_F_EC_GROUP_GET_CURVE_GF2M,
 449               ERR_R_SHOULD_NOT_HAVE_BEEN_CALLED);
 450         return 0;
 451     }
 452     return group->meth->group_get_curve(group, p, a, b, ctx);
 453 }
 454 #endif
 455
 456 int EC_GROUP_get_degree(const EC_GROUP *group)
 457 {
 458     if (group->meth->group_get_degree == 0) {
 459         ECerr(EC_F_EC_GROUP_GET_DEGREE, ERR_R_SHOULD_NOT_HAVE_BEEN_CALLED);
 460         return 0;
 461     }
 462     return group->meth->group_get_degree(group);
 463 }
 464
 465 int EC_GROUP_check_discriminant(const EC_GROUP *group, BN_CTX *ctx)
 466 {
 467     if (group->meth->group_check_discriminant == 0) {
 468         ECerr(EC_F_EC_GROUP_CHECK_DISCRIMINANT,
 469               ERR_R_SHOULD_NOT_HAVE_BEEN_CALLED);
 470         return 0;
 471     }
 472     return group->meth->group_check_discriminant(group, ctx);
 473 }
 474
 475 int EC_GROUP_cmp(const EC_GROUP *a, const EC_GROUP *b, BN_CTX *ctx)
 476 {
 477     int r = 0;
 478     BIGNUM *a1, *a2, *a3, *b1, *b2, *b3;
 479     BN_CTX *ctx_new = NULL;
 480
 481     /* compare the field types */
 482     if (EC_METHOD_get_field_type(EC_GROUP_method_of(a)) !=
 483         EC_METHOD_get_field_type(EC_GROUP_method_of(b)))
 484         return 1;
 485     /* compare the curve name (if present in both) */
 486     if (EC_GROUP_get_curve_name(a) && EC_GROUP_get_curve_name(b) &&
 487         EC_GROUP_get_curve_name(a) != EC_GROUP_get_curve_name(b))
 488         return 1;
 489
 490     if (!ctx)
 491         ctx_new = ctx = BN_CTX_new();
 492     if (!ctx)
 493         return -1;
 494
 495     BN_CTX_start(ctx);
 496     a1 = BN_CTX_get(ctx);
 497     a2 = BN_CTX_get(ctx);
 498     a3 = BN_CTX_get(ctx);
 499     b1 = BN_CTX_get(ctx);
 500     b2 = BN_CTX_get(ctx);
 501     b3 = BN_CTX_get(ctx);
 502     if (!b3) {
 503         BN_CTX_end(ctx);
 504         BN_CTX_free(ctx_new);
 505         return -1;
 506     }
 507
 508     /*
 509      * XXX This approach assumes that the external representation of curves
 510      * over the same field type is the same.
 511      */
 512     if (!a->meth->group_get_curve(a, a1, a2, a3, ctx) ||
 513         !b->meth->group_get_curve(b, b1, b2, b3, ctx))
 514         r = 1;
 515
 516     if (r || BN_cmp(a1, b1) || BN_cmp(a2, b2) || BN_cmp(a3, b3))
 517         r = 1;
 518
 519     /* XXX EC_POINT_cmp() assumes that the methods are equal */
 520     if (r || EC_POINT_cmp(a, EC_GROUP_get0_generator(a),
 521                           EC_GROUP_get0_generator(b), ctx))
 522         r = 1;
 523
 524     if (!r) {
 525         /* compare the order and cofactor */
 526         if (!EC_GROUP_get_order(a, a1, ctx) ||
 527             !EC_GROUP_get_order(b, b1, ctx) ||
 528             !EC_GROUP_get_cofactor(a, a2, ctx) ||
 529             !EC_GROUP_get_cofactor(b, b2, ctx)) {
 530             BN_CTX_end(ctx);
 531             BN_CTX_free(ctx_new);
 532             return -1;
 533         }
 534         if (BN_cmp(a1, b1) || BN_cmp(a2, b2))
 535             r = 1;
 536     }
 537
 538     BN_CTX_end(ctx);
 539     BN_CTX_free(ctx_new);
 540
 541     return r;
 542 }
 543
 544 /* this has 'package' visibility */
 545 int EC_EX_DATA_set_data(EC_EXTRA_DATA **ex_data, void *data,
 546                         void *(*dup_func) (void *),
 547                         void (*free_func) (void *),
 548                         void (*clear_free_func) (void *))
 549 {
 550     EC_EXTRA_DATA *d;
 551
 552     if (ex_data == NULL)
 553         return 0;
 554
 555     for (d = *ex_data; d != NULL; d = d->next) {
 556         if (d->dup_func == dup_func && d->free_func == free_func
 557             && d->clear_free_func == clear_free_func) {
 558             ECerr(EC_F_EC_EX_DATA_SET_DATA, EC_R_SLOT_FULL);
 559             return 0;
 560         }
 561     }
 562
 563     if (data == NULL)
 564         /* no explicit entry needed */
 565         return 1;
 566
 567     d = OPENSSL_malloc(sizeof *d);
 568     if (d == NULL)
 569         return 0;
 570
 571     d->data = data;
 572     d->dup_func = dup_func;
 573     d->free_func = free_func;
 574     d->clear_free_func = clear_free_func;
 575
 576     d->next = *ex_data;
 577     *ex_data = d;
 578
 579     return 1;
 580 }
 581
 582 /* this has 'package' visibility */
 583 void *EC_EX_DATA_get_data(const EC_EXTRA_DATA *ex_data,
 584                           void *(*dup_func) (void *),
 585                           void (*free_func) (void *),
 586                           void (*clear_free_func) (void *))
 587 {
 588     const EC_EXTRA_DATA *d;
 589
 590     for (d = ex_data; d != NULL; d = d->next) {
 591         if (d->dup_func == dup_func && d->free_func == free_func
 592             && d->clear_free_func == clear_free_func)
 593             return d->data;
 594     }
 595
 596     return NULL;
 597 }
 598
 599 /* this has 'package' visibility */
 600 void EC_EX_DATA_free_data(EC_EXTRA_DATA **ex_data,
 601                           void *(*dup_func) (void *),
 602                           void (*free_func) (void *),
 603                           void (*clear_free_func) (void *))
 604 {
 605     EC_EXTRA_DATA **p;
 606
 607     if (ex_data == NULL)
 608         return;
 609
 610     for (p = ex_data; *p != NULL; p = &((*p)->next)) {
 611         if ((*p)->dup_func == dup_func && (*p)->free_func == free_func
 612             && (*p)->clear_free_func == clear_free_func) {
 613             EC_EXTRA_DATA *next = (*p)->next;
 614
 615             (*p)->free_func((*p)->data);
 616             OPENSSL_free(*p);
 617
 618             *p = next;
 619             return;
 620         }
 621     }
 622 }
 623
 624 /* this has 'package' visibility */
 625 void EC_EX_DATA_clear_free_data(EC_EXTRA_DATA **ex_data,
 626                                 void *(*dup_func) (void *),
 627                                 void (*free_func) (void *),
 628                                 void (*clear_free_func) (void *))
 629 {
 630     EC_EXTRA_DATA **p;
 631
 632     if (ex_data == NULL)
 633         return;
 634
 635     for (p = ex_data; *p != NULL; p = &((*p)->next)) {
 636         if ((*p)->dup_func == dup_func && (*p)->free_func == free_func
 637             && (*p)->clear_free_func == clear_free_func) {
 638             EC_EXTRA_DATA *next = (*p)->next;
 639
 640             (*p)->clear_free_func((*p)->data);
 641             OPENSSL_free(*p);
 642
 643             *p = next;
 644             return;
 645         }
 646     }
 647 }
 648
 649 /* this has 'package' visibility */
 650 void EC_EX_DATA_free_all_data(EC_EXTRA_DATA **ex_data)
 651 {
 652     EC_EXTRA_DATA *d;
 653
 654     if (ex_data == NULL)
 655         return;
 656
 657     d = *ex_data;
 658     while (d) {
 659         EC_EXTRA_DATA *next = d->next;
 660
 661         d->free_func(d->data);
 662         OPENSSL_free(d);
 663
 664         d = next;
 665     }
 666     *ex_data = NULL;
 667 }
 668
 669 /* this has 'package' visibility */
 670 void EC_EX_DATA_clear_free_all_data(EC_EXTRA_DATA **ex_data)
 671 {
 672     EC_EXTRA_DATA *d;
 673
 674     if (ex_data == NULL)
 675         return;
 676
 677     d = *ex_data;
 678     while (d) {
 679         EC_EXTRA_DATA *next = d->next;
 680
 681         d->clear_free_func(d->data);
 682         OPENSSL_free(d);
 683
 684         d = next;
 685     }
 686     *ex_data = NULL;
 687 }
 688
 689 /* functions for EC_POINT objects */
 690
 691 EC_POINT *EC_POINT_new(const EC_GROUP *group)
 692 {
 693     EC_POINT *ret;
 694
 695     if (group == NULL) {
 696         ECerr(EC_F_EC_POINT_NEW, ERR_R_PASSED_NULL_PARAMETER);
 697         return NULL;
 698     }
 699     if (group->meth->point_init == 0) {
 700         ECerr(EC_F_EC_POINT_NEW, ERR_R_SHOULD_NOT_HAVE_BEEN_CALLED);
 701         return NULL;
 702     }
 703
 704     ret = OPENSSL_malloc(sizeof *ret);
 705     if (ret == NULL) {
 706         ECerr(EC_F_EC_POINT_NEW, ERR_R_MALLOC_FAILURE);
 707         return NULL;
 708     }
 709
 710     ret->meth = group->meth;
 711
 712     if (!ret->meth->point_init(ret)) {
 713         OPENSSL_free(ret);
 714         return NULL;
 715     }
 716
 717     return ret;
 718 }
 719
 720 void EC_POINT_free(EC_POINT *point)
 721 {
 722     if (!point)
 723         return;
 724
 725     if (point->meth->point_finish != 0)
 726         point->meth->point_finish(point);
 727     OPENSSL_free(point);
 728 }
 729
 730 void EC_POINT_clear_free(EC_POINT *point)
 731 {
 732     if (!point)
 733         return;
 734
 735     if (point->meth->point_clear_finish != 0)
 736         point->meth->point_clear_finish(point);
 737     else if (point->meth->point_finish != 0)
 738         point->meth->point_finish(point);
 739     OPENSSL_clear_free(point, sizeof *point);
 740 }
 741
 742 int EC_POINT_copy(EC_POINT *dest, const EC_POINT *src)
 743 {
 744     if (dest->meth->point_copy == 0) {
 745         ECerr(EC_F_EC_POINT_COPY, ERR_R_SHOULD_NOT_HAVE_BEEN_CALLED);
 746         return 0;
 747     }
 748     if (dest->meth != src->meth) {
 749         ECerr(EC_F_EC_POINT_COPY, EC_R_INCOMPATIBLE_OBJECTS);
 750         return 0;
 751     }
 752     if (dest == src)
 753         return 1;
 754     return dest->meth->point_copy(dest, src);
 755 }
 756
 757 EC_POINT *EC_POINT_dup(const EC_POINT *a, const EC_GROUP *group)
 758 {
 759     EC_POINT *t;
 760     int r;
 761
 762     if (a == NULL)
 763         return NULL;
 764
 765     t = EC_POINT_new(group);
 766     if (t == NULL)
 767         return (NULL);
 768     r = EC_POINT_copy(t, a);
 769     if (!r) {
 770         EC_POINT_free(t);
 771         return NULL;
 772     }
 773     return t;
 774 }
 775
 776 const EC_METHOD *EC_POINT_method_of(const EC_POINT *point)
 777 {
 778     return point->meth;
 779 }
 780
 781 int EC_POINT_set_to_infinity(const EC_GROUP *group, EC_POINT *point)
 782 {
 783     if (group->meth->point_set_to_infinity == 0) {
 784         ECerr(EC_F_EC_POINT_SET_TO_INFINITY,
 785               ERR_R_SHOULD_NOT_HAVE_BEEN_CALLED);
 786         return 0;
 787     }
 788     if (group->meth != point->meth) {
 789         ECerr(EC_F_EC_POINT_SET_TO_INFINITY, EC_R_INCOMPATIBLE_OBJECTS);
 790         return 0;
 791     }
 792     return group->meth->point_set_to_infinity(group, point);
 793 }
 794
 795 int EC_POINT_set_Jprojective_coordinates_GFp(const EC_GROUP *group,
 796                                              EC_POINT *point, const BIGNUM *x,
 797                                              const BIGNUM *y, const BIGNUM *z,
 798                                              BN_CTX *ctx)
 799 {
 800     if (group->meth->point_set_Jprojective_coordinates_GFp == 0) {
 801         ECerr(EC_F_EC_POINT_SET_JPROJECTIVE_COORDINATES_GFP,
 802               ERR_R_SHOULD_NOT_HAVE_BEEN_CALLED);
 803         return 0;
 804     }
 805     if (group->meth != point->meth) {
 806         ECerr(EC_F_EC_POINT_SET_JPROJECTIVE_COORDINATES_GFP,
 807               EC_R_INCOMPATIBLE_OBJECTS);
 808         return 0;
 809     }
 810     return group->meth->point_set_Jprojective_coordinates_GFp(group, point, x,
 811                                                               y, z, ctx);
 812 }
 813
 814 int EC_POINT_get_Jprojective_coordinates_GFp(const EC_GROUP *group,
 815                                              const EC_POINT *point, BIGNUM *x,
 816                                              BIGNUM *y, BIGNUM *z,
 817                                              BN_CTX *ctx)
 818 {
 819     if (group->meth->point_get_Jprojective_coordinates_GFp == 0) {
 820         ECerr(EC_F_EC_POINT_GET_JPROJECTIVE_COORDINATES_GFP,
 821               ERR_R_SHOULD_NOT_HAVE_BEEN_CALLED);
 822         return 0;
 823     }
 824     if (group->meth != point->meth) {
 825         ECerr(EC_F_EC_POINT_GET_JPROJECTIVE_COORDINATES_GFP,
 826               EC_R_INCOMPATIBLE_OBJECTS);
 827         return 0;
 828     }
 829     return group->meth->point_get_Jprojective_coordinates_GFp(group, point, x,
 830                                                               y, z, ctx);
 831 }
 832
 833 int EC_POINT_set_affine_coordinates_GFp(const EC_GROUP *group,
 834                                         EC_POINT *point, const BIGNUM *x,
 835                                         const BIGNUM *y, BN_CTX *ctx)
 836 {
 837     if (group->meth->point_set_affine_coordinates == 0) {
 838         ECerr(EC_F_EC_POINT_SET_AFFINE_COORDINATES_GFP,
 839               ERR_R_SHOULD_NOT_HAVE_BEEN_CALLED);
 840         return 0;
 841     }
 842     if (group->meth != point->meth) {
 843         ECerr(EC_F_EC_POINT_SET_AFFINE_COORDINATES_GFP,
 844               EC_R_INCOMPATIBLE_OBJECTS);
 845         return 0;
 846     }
 847     return group->meth->point_set_affine_coordinates(group, point, x, y, ctx);
 848 }
 849
 850 #ifndef OPENSSL_NO_EC2M
 851 int EC_POINT_set_affine_coordinates_GF2m(const EC_GROUP *group,
 852                                          EC_POINT *point, const BIGNUM *x,
 853                                          const BIGNUM *y, BN_CTX *ctx)
 854 {
 855     if (group->meth->point_set_affine_coordinates == 0) {
 856         ECerr(EC_F_EC_POINT_SET_AFFINE_COORDINATES_GF2M,
 857               ERR_R_SHOULD_NOT_HAVE_BEEN_CALLED);
 858         return 0;
 859     }
 860     if (group->meth != point->meth) {
 861         ECerr(EC_F_EC_POINT_SET_AFFINE_COORDINATES_GF2M,
 862               EC_R_INCOMPATIBLE_OBJECTS);
 863         return 0;
 864     }
 865     return group->meth->point_set_affine_coordinates(group, point, x, y, ctx);
 866 }
 867 #endif
 868
 869 int EC_POINT_get_affine_coordinates_GFp(const EC_GROUP *group,
 870                                         const EC_POINT *point, BIGNUM *x,
 871                                         BIGNUM *y, BN_CTX *ctx)
 872 {
 873     if (group->meth->point_get_affine_coordinates == 0) {
 874         ECerr(EC_F_EC_POINT_GET_AFFINE_COORDINATES_GFP,
 875               ERR_R_SHOULD_NOT_HAVE_BEEN_CALLED);
 876         return 0;
 877     }
 878     if (group->meth != point->meth) {
 879         ECerr(EC_F_EC_POINT_GET_AFFINE_COORDINATES_GFP,
 880               EC_R_INCOMPATIBLE_OBJECTS);
 881         return 0;
 882     }
 883     return group->meth->point_get_affine_coordinates(group, point, x, y, ctx);
 884 }
 885
 886 #ifndef OPENSSL_NO_EC2M
 887 int EC_POINT_get_affine_coordinates_GF2m(const EC_GROUP *group,
 888                                          const EC_POINT *point, BIGNUM *x,
 889                                          BIGNUM *y, BN_CTX *ctx)
 890 {
 891     if (group->meth->point_get_affine_coordinates == 0) {
 892         ECerr(EC_F_EC_POINT_GET_AFFINE_COORDINATES_GF2M,
 893               ERR_R_SHOULD_NOT_HAVE_BEEN_CALLED);
 894         return 0;
 895     }
 896     if (group->meth != point->meth) {
 897         ECerr(EC_F_EC_POINT_GET_AFFINE_COORDINATES_GF2M,
 898               EC_R_INCOMPATIBLE_OBJECTS);
 899         return 0;
 900     }
 901     return group->meth->point_get_affine_coordinates(group, point, x, y, ctx);
 902 }
 903 #endif
 904
 905 int EC_POINT_add(const EC_GROUP *group, EC_POINT *r, const EC_POINT *a,
 906                  const EC_POINT *b, BN_CTX *ctx)
 907 {
 908     if (group->meth->add == 0) {
 909         ECerr(EC_F_EC_POINT_ADD, ERR_R_SHOULD_NOT_HAVE_BEEN_CALLED);
 910         return 0;
 911     }
 912     if ((group->meth != r->meth) || (r->meth != a->meth)
 913         || (a->meth != b->meth)) {
 914         ECerr(EC_F_EC_POINT_ADD, EC_R_INCOMPATIBLE_OBJECTS);
 915         return 0;
 916     }
 917     return group->meth->add(group, r, a, b, ctx);
 918 }
 919
 920 int EC_POINT_dbl(const EC_GROUP *group, EC_POINT *r, const EC_POINT *a,
 921                  BN_CTX *ctx)
 922 {
 923     if (group->meth->dbl == 0) {
 924         ECerr(EC_F_EC_POINT_DBL, ERR_R_SHOULD_NOT_HAVE_BEEN_CALLED);
 925         return 0;
 926     }
 927     if ((group->meth != r->meth) || (r->meth != a->meth)) {
 928         ECerr(EC_F_EC_POINT_DBL, EC_R_INCOMPATIBLE_OBJECTS);
 929         return 0;
 930     }
 931     return group->meth->dbl(group, r, a, ctx);
 932 }
 933
 934 int EC_POINT_invert(const EC_GROUP *group, EC_POINT *a, BN_CTX *ctx)
 935 {
 936     if (group->meth->invert == 0) {
 937         ECerr(EC_F_EC_POINT_INVERT, ERR_R_SHOULD_NOT_HAVE_BEEN_CALLED);
 938         return 0;
 939     }
 940     if (group->meth != a->meth) {
 941         ECerr(EC_F_EC_POINT_INVERT, EC_R_INCOMPATIBLE_OBJECTS);
 942         return 0;
 943     }
 944     return group->meth->invert(group, a, ctx);
 945 }
 946
 947 int EC_POINT_is_at_infinity(const EC_GROUP *group, const EC_POINT *point)
 948 {
 949     if (group->meth->is_at_infinity == 0) {
 950         ECerr(EC_F_EC_POINT_IS_AT_INFINITY,
 951               ERR_R_SHOULD_NOT_HAVE_BEEN_CALLED);
 952         return 0;
 953     }
 954     if (group->meth != point->meth) {
 955         ECerr(EC_F_EC_POINT_IS_AT_INFINITY, EC_R_INCOMPATIBLE_OBJECTS);
 956         return 0;
 957     }
 958     return group->meth->is_at_infinity(group, point);
 959 }
 960
 961 int EC_POINT_is_on_curve(const EC_GROUP *group, const EC_POINT *point,
 962                          BN_CTX *ctx)
 963 {
 964     if (group->meth->is_on_curve == 0) {
 965         ECerr(EC_F_EC_POINT_IS_ON_CURVE, ERR_R_SHOULD_NOT_HAVE_BEEN_CALLED);
 966         return 0;
 967     }
 968     if (group->meth != point->meth) {
 969         ECerr(EC_F_EC_POINT_IS_ON_CURVE, EC_R_INCOMPATIBLE_OBJECTS);
 970         return 0;
 971     }
 972     return group->meth->is_on_curve(group, point, ctx);
 973 }
 974
 975 int EC_POINT_cmp(const EC_GROUP *group, const EC_POINT *a, const EC_POINT *b,
 976                  BN_CTX *ctx)
 977 {
 978     if (group->meth->point_cmp == 0) {
 979         ECerr(EC_F_EC_POINT_CMP, ERR_R_SHOULD_NOT_HAVE_BEEN_CALLED);
 980         return -1;
 981     }
 982     if ((group->meth != a->meth) || (a->meth != b->meth)) {
 983         ECerr(EC_F_EC_POINT_CMP, EC_R_INCOMPATIBLE_OBJECTS);
 984         return -1;
 985     }
 986     return group->meth->point_cmp(group, a, b, ctx);
 987 }
 988
 989 int EC_POINT_make_affine(const EC_GROUP *group, EC_POINT *point, BN_CTX *ctx)
 990 {
 991     if (group->meth->make_affine == 0) {
 992         ECerr(EC_F_EC_POINT_MAKE_AFFINE, ERR_R_SHOULD_NOT_HAVE_BEEN_CALLED);
 993         return 0;
 994     }
 995     if (group->meth != point->meth) {
 996         ECerr(EC_F_EC_POINT_MAKE_AFFINE, EC_R_INCOMPATIBLE_OBJECTS);
 997         return 0;
 998     }
 999     return group->meth->make_affine(group, point, ctx);
1000 }
1001
1002 int EC_POINTs_make_affine(const EC_GROUP *group, size_t num,
1003                           EC_POINT *points[], BN_CTX *ctx)
1004 {
1005     size_t i;
1006
1007     if (group->meth->points_make_affine == 0) {
1008         ECerr(EC_F_EC_POINTS_MAKE_AFFINE, ERR_R_SHOULD_NOT_HAVE_BEEN_CALLED);
1009         return 0;
1010     }
1011     for (i = 0; i < num; i++) {
1012         if (group->meth != points[i]->meth) {
1013             ECerr(EC_F_EC_POINTS_MAKE_AFFINE, EC_R_INCOMPATIBLE_OBJECTS);
1014             return 0;
1015         }
1016     }
1017     return group->meth->points_make_affine(group, num, points, ctx);
1018 }
1019
1020 /*
1021  * Functions for point multiplication. If group->meth->mul is 0, we use the
1022  * wNAF-based implementations in ec_mult.c; otherwise we dispatch through
1023  * methods.
1024  */
1025
1026 int EC_POINTs_mul(const EC_GROUP *group, EC_POINT *r, const BIGNUM *scalar,
1027                   size_t num, const EC_POINT *points[],
1028                   const BIGNUM *scalars[], BN_CTX *ctx)
1029 {
1030     if (group->meth->mul == 0)
1031         /* use default */
1032         return ec_wNAF_mul(group, r, scalar, num, points, scalars, ctx);
1033
1034     return group->meth->mul(group, r, scalar, num, points, scalars, ctx);
1035 }
1036
1037 int EC_POINT_mul(const EC_GROUP *group, EC_POINT *r, const BIGNUM *g_scalar,
1038                  const EC_POINT *point, const BIGNUM *p_scalar, BN_CTX *ctx)
1039 {
1040     /* just a convenient interface to EC_POINTs_mul() */
1041
1042     const EC_POINT *points[1];
1043     const BIGNUM *scalars[1];
1044
1045     points[0] = point;
1046     scalars[0] = p_scalar;
1047
1048     return EC_POINTs_mul(group, r, g_scalar,
1049                          (point != NULL
1050                           && p_scalar != NULL), points, scalars, ctx);
1051 }
1052
1053 int EC_GROUP_precompute_mult(EC_GROUP *group, BN_CTX *ctx)
1054 {
1055     if (group->meth->mul == 0)
1056         /* use default */
1057         return ec_wNAF_precompute_mult(group, ctx);
1058
1059     if (group->meth->precompute_mult != 0)
1060         return group->meth->precompute_mult(group, ctx);
1061     else
1062         return 1;               /* nothing to do, so report success */
1063 }
1064
1065 int EC_GROUP_have_precompute_mult(const EC_GROUP *group)
1066 {
1067     if (group->meth->mul == 0)
1068         /* use default */
1069         return ec_wNAF_have_precompute_mult(group);
1070
1071     if (group->meth->have_precompute_mult != 0)
1072         return group->meth->have_precompute_mult(group);
1073     else
1074         return 0;               /* cannot tell whether precomputation has
1075                                  * been performed */
1076 }
1077
1078 /*
1079  * ec_precompute_mont_data sets |group->mont_data| from |group->order| and
1080  * returns one on success. On error it returns zero.
1081  */
1082 int ec_precompute_mont_data(EC_GROUP *group)
1083 {
1084     BN_CTX *ctx = BN_CTX_new();
1085     int ret = 0;
1086
1087     BN_MONT_CTX_free(group->mont_data);
1088     group->mont_data = NULL;
1089
1090     if (ctx == NULL)
1091         goto err;
1092
1093     group->mont_data = BN_MONT_CTX_new();
1094     if (!group->mont_data)
1095         goto err;
1096
1097     if (!BN_MONT_CTX_set(group->mont_data, group->order, ctx)) {
1098         BN_MONT_CTX_free(group->mont_data);
1099         group->mont_data = NULL;
1100         goto err;
1101     }
1102
1103     ret = 1;
1104
1105  err:
1106
1107     BN_CTX_free(ctx);
1108     return ret;
1109 }