2 * Copyright 2001-2018 The OpenSSL Project Authors. All Rights Reserved.
3 * Copyright (c) 2002, Oracle and/or its affiliates. All rights reserved
5 * Licensed under the OpenSSL license (the "License"). You may not use
6 * this file except in compliance with the License. You can obtain a copy
7 * in the file LICENSE in the source distribution or at
8 * https://www.openssl.org/source/license.html
13 #include <openssl/err.h>
14 #include <openssl/opensslv.h>
18 /* functions for EC_GROUP objects */
20 EC_GROUP *EC_GROUP_new(const EC_METHOD *meth)
25 ECerr(EC_F_EC_GROUP_NEW, EC_R_SLOT_FULL);
28 if (meth->group_init == 0) {
29 ECerr(EC_F_EC_GROUP_NEW, ERR_R_SHOULD_NOT_HAVE_BEEN_CALLED);
33 ret = OPENSSL_zalloc(sizeof(*ret));
35 ECerr(EC_F_EC_GROUP_NEW, ERR_R_MALLOC_FAILURE);
40 if ((ret->meth->flags & EC_FLAGS_CUSTOM_CURVE) == 0) {
41 ret->order = BN_new();
42 if (ret->order == NULL)
44 ret->cofactor = BN_new();
45 if (ret->cofactor == NULL)
48 ret->asn1_flag = OPENSSL_EC_NAMED_CURVE;
49 ret->asn1_form = POINT_CONVERSION_UNCOMPRESSED;
50 if (!meth->group_init(ret))
56 BN_free(ret->cofactor);
61 void EC_pre_comp_free(EC_GROUP *group)
63 switch (group->pre_comp_type) {
67 #ifdef ECP_NISTZ256_ASM
68 EC_nistz256_pre_comp_free(group->pre_comp.nistz256);
71 #ifndef OPENSSL_NO_EC_NISTP_64_GCC_128
73 EC_nistp224_pre_comp_free(group->pre_comp.nistp224);
76 EC_nistp256_pre_comp_free(group->pre_comp.nistp256);
79 EC_nistp521_pre_comp_free(group->pre_comp.nistp521);
88 EC_ec_pre_comp_free(group->pre_comp.ec);
91 group->pre_comp.ec = NULL;
94 void EC_GROUP_free(EC_GROUP *group)
99 if (group->meth->group_finish != 0)
100 group->meth->group_finish(group);
102 EC_pre_comp_free(group);
103 BN_MONT_CTX_free(group->mont_data);
104 EC_POINT_free(group->generator);
105 BN_free(group->order);
106 BN_free(group->cofactor);
107 OPENSSL_free(group->seed);
111 void EC_GROUP_clear_free(EC_GROUP *group)
116 if (group->meth->group_clear_finish != 0)
117 group->meth->group_clear_finish(group);
118 else if (group->meth->group_finish != 0)
119 group->meth->group_finish(group);
121 EC_pre_comp_free(group);
122 BN_MONT_CTX_free(group->mont_data);
123 EC_POINT_clear_free(group->generator);
124 BN_clear_free(group->order);
125 BN_clear_free(group->cofactor);
126 OPENSSL_clear_free(group->seed, group->seed_len);
127 OPENSSL_clear_free(group, sizeof(*group));
130 int EC_GROUP_copy(EC_GROUP *dest, const EC_GROUP *src)
132 if (dest->meth->group_copy == 0) {
133 ECerr(EC_F_EC_GROUP_COPY, ERR_R_SHOULD_NOT_HAVE_BEEN_CALLED);
136 if (dest->meth != src->meth) {
137 ECerr(EC_F_EC_GROUP_COPY, EC_R_INCOMPATIBLE_OBJECTS);
143 dest->curve_name = src->curve_name;
145 /* Copy precomputed */
146 dest->pre_comp_type = src->pre_comp_type;
147 switch (src->pre_comp_type) {
149 dest->pre_comp.ec = NULL;
152 #ifdef ECP_NISTZ256_ASM
153 dest->pre_comp.nistz256 = EC_nistz256_pre_comp_dup(src->pre_comp.nistz256);
156 #ifndef OPENSSL_NO_EC_NISTP_64_GCC_128
158 dest->pre_comp.nistp224 = EC_nistp224_pre_comp_dup(src->pre_comp.nistp224);
161 dest->pre_comp.nistp256 = EC_nistp256_pre_comp_dup(src->pre_comp.nistp256);
164 dest->pre_comp.nistp521 = EC_nistp521_pre_comp_dup(src->pre_comp.nistp521);
173 dest->pre_comp.ec = EC_ec_pre_comp_dup(src->pre_comp.ec);
177 if (src->mont_data != NULL) {
178 if (dest->mont_data == NULL) {
179 dest->mont_data = BN_MONT_CTX_new();
180 if (dest->mont_data == NULL)
183 if (!BN_MONT_CTX_copy(dest->mont_data, src->mont_data))
186 /* src->generator == NULL */
187 BN_MONT_CTX_free(dest->mont_data);
188 dest->mont_data = NULL;
191 if (src->generator != NULL) {
192 if (dest->generator == NULL) {
193 dest->generator = EC_POINT_new(dest);
194 if (dest->generator == NULL)
197 if (!EC_POINT_copy(dest->generator, src->generator))
200 /* src->generator == NULL */
201 EC_POINT_clear_free(dest->generator);
202 dest->generator = NULL;
205 if ((src->meth->flags & EC_FLAGS_CUSTOM_CURVE) == 0) {
206 if (!BN_copy(dest->order, src->order))
208 if (!BN_copy(dest->cofactor, src->cofactor))
212 dest->asn1_flag = src->asn1_flag;
213 dest->asn1_form = src->asn1_form;
216 OPENSSL_free(dest->seed);
217 if ((dest->seed = OPENSSL_malloc(src->seed_len)) == NULL) {
218 ECerr(EC_F_EC_GROUP_COPY, ERR_R_MALLOC_FAILURE);
221 if (!memcpy(dest->seed, src->seed, src->seed_len))
223 dest->seed_len = src->seed_len;
225 OPENSSL_free(dest->seed);
230 return dest->meth->group_copy(dest, src);
233 EC_GROUP *EC_GROUP_dup(const EC_GROUP *a)
241 if ((t = EC_GROUP_new(a->meth)) == NULL)
243 if (!EC_GROUP_copy(t, a))
256 const EC_METHOD *EC_GROUP_method_of(const EC_GROUP *group)
261 int EC_METHOD_get_field_type(const EC_METHOD *meth)
263 return meth->field_type;
266 static int ec_precompute_mont_data(EC_GROUP *);
268 int EC_GROUP_set_generator(EC_GROUP *group, const EC_POINT *generator,
269 const BIGNUM *order, const BIGNUM *cofactor)
271 if (generator == NULL) {
272 ECerr(EC_F_EC_GROUP_SET_GENERATOR, ERR_R_PASSED_NULL_PARAMETER);
276 if (group->generator == NULL) {
277 group->generator = EC_POINT_new(group);
278 if (group->generator == NULL)
281 if (!EC_POINT_copy(group->generator, generator))
285 if (!BN_copy(group->order, order))
288 BN_zero(group->order);
290 if (cofactor != NULL) {
291 if (!BN_copy(group->cofactor, cofactor))
294 BN_zero(group->cofactor);
297 * Some groups have an order with
298 * factors of two, which makes the Montgomery setup fail.
299 * |group->mont_data| will be NULL in this case.
301 if (BN_is_odd(group->order)) {
302 return ec_precompute_mont_data(group);
305 BN_MONT_CTX_free(group->mont_data);
306 group->mont_data = NULL;
310 const EC_POINT *EC_GROUP_get0_generator(const EC_GROUP *group)
312 return group->generator;
315 BN_MONT_CTX *EC_GROUP_get_mont_data(const EC_GROUP *group)
317 return group->mont_data;
320 int EC_GROUP_get_order(const EC_GROUP *group, BIGNUM *order, BN_CTX *ctx)
322 if (group->order == NULL)
324 if (!BN_copy(order, group->order))
327 return !BN_is_zero(order);
330 const BIGNUM *EC_GROUP_get0_order(const EC_GROUP *group)
335 int EC_GROUP_order_bits(const EC_GROUP *group)
337 return group->meth->group_order_bits(group);
340 int EC_GROUP_get_cofactor(const EC_GROUP *group, BIGNUM *cofactor,
344 if (group->cofactor == NULL)
346 if (!BN_copy(cofactor, group->cofactor))
349 return !BN_is_zero(group->cofactor);
352 const BIGNUM *EC_GROUP_get0_cofactor(const EC_GROUP *group)
354 return group->cofactor;
357 void EC_GROUP_set_curve_name(EC_GROUP *group, int nid)
359 group->curve_name = nid;
362 int EC_GROUP_get_curve_name(const EC_GROUP *group)
364 return group->curve_name;
367 void EC_GROUP_set_asn1_flag(EC_GROUP *group, int flag)
369 group->asn1_flag = flag;
372 int EC_GROUP_get_asn1_flag(const EC_GROUP *group)
374 return group->asn1_flag;
377 void EC_GROUP_set_point_conversion_form(EC_GROUP *group,
378 point_conversion_form_t form)
380 group->asn1_form = form;
383 point_conversion_form_t EC_GROUP_get_point_conversion_form(const EC_GROUP
386 return group->asn1_form;
389 size_t EC_GROUP_set_seed(EC_GROUP *group, const unsigned char *p, size_t len)
391 OPENSSL_free(group->seed);
398 if ((group->seed = OPENSSL_malloc(len)) == NULL) {
399 ECerr(EC_F_EC_GROUP_SET_SEED, ERR_R_MALLOC_FAILURE);
402 memcpy(group->seed, p, len);
403 group->seed_len = len;
408 unsigned char *EC_GROUP_get0_seed(const EC_GROUP *group)
413 size_t EC_GROUP_get_seed_len(const EC_GROUP *group)
415 return group->seed_len;
418 int EC_GROUP_set_curve(EC_GROUP *group, const BIGNUM *p, const BIGNUM *a,
419 const BIGNUM *b, BN_CTX *ctx)
421 if (group->meth->group_set_curve == 0) {
422 ECerr(EC_F_EC_GROUP_SET_CURVE, ERR_R_SHOULD_NOT_HAVE_BEEN_CALLED);
425 return group->meth->group_set_curve(group, p, a, b, ctx);
428 int EC_GROUP_get_curve(const EC_GROUP *group, BIGNUM *p, BIGNUM *a, BIGNUM *b,
431 if (group->meth->group_get_curve == NULL) {
432 ECerr(EC_F_EC_GROUP_GET_CURVE, ERR_R_SHOULD_NOT_HAVE_BEEN_CALLED);
435 return group->meth->group_get_curve(group, p, a, b, ctx);
438 int EC_GROUP_set_curve_GFp(EC_GROUP *group, const BIGNUM *p, const BIGNUM *a,
439 const BIGNUM *b, BN_CTX *ctx)
441 return EC_GROUP_set_curve(group, p, a, b, ctx);
444 int EC_GROUP_get_curve_GFp(const EC_GROUP *group, BIGNUM *p, BIGNUM *a,
445 BIGNUM *b, BN_CTX *ctx)
447 return EC_GROUP_get_curve(group, p, a, b, ctx);
450 #ifndef OPENSSL_NO_EC2M
451 int EC_GROUP_set_curve_GF2m(EC_GROUP *group, const BIGNUM *p, const BIGNUM *a,
452 const BIGNUM *b, BN_CTX *ctx)
454 return EC_GROUP_set_curve(group, p, a, b, ctx);
457 int EC_GROUP_get_curve_GF2m(const EC_GROUP *group, BIGNUM *p, BIGNUM *a,
458 BIGNUM *b, BN_CTX *ctx)
460 return EC_GROUP_get_curve(group, p, a, b, ctx);
464 int EC_GROUP_get_degree(const EC_GROUP *group)
466 if (group->meth->group_get_degree == 0) {
467 ECerr(EC_F_EC_GROUP_GET_DEGREE, ERR_R_SHOULD_NOT_HAVE_BEEN_CALLED);
470 return group->meth->group_get_degree(group);
473 int EC_GROUP_check_discriminant(const EC_GROUP *group, BN_CTX *ctx)
475 if (group->meth->group_check_discriminant == 0) {
476 ECerr(EC_F_EC_GROUP_CHECK_DISCRIMINANT,
477 ERR_R_SHOULD_NOT_HAVE_BEEN_CALLED);
480 return group->meth->group_check_discriminant(group, ctx);
483 int EC_GROUP_cmp(const EC_GROUP *a, const EC_GROUP *b, BN_CTX *ctx)
486 BIGNUM *a1, *a2, *a3, *b1, *b2, *b3;
487 BN_CTX *ctx_new = NULL;
489 /* compare the field types */
490 if (EC_METHOD_get_field_type(EC_GROUP_method_of(a)) !=
491 EC_METHOD_get_field_type(EC_GROUP_method_of(b)))
493 /* compare the curve name (if present in both) */
494 if (EC_GROUP_get_curve_name(a) && EC_GROUP_get_curve_name(b) &&
495 EC_GROUP_get_curve_name(a) != EC_GROUP_get_curve_name(b))
497 if (a->meth->flags & EC_FLAGS_CUSTOM_CURVE)
501 ctx_new = ctx = BN_CTX_new();
506 a1 = BN_CTX_get(ctx);
507 a2 = BN_CTX_get(ctx);
508 a3 = BN_CTX_get(ctx);
509 b1 = BN_CTX_get(ctx);
510 b2 = BN_CTX_get(ctx);
511 b3 = BN_CTX_get(ctx);
514 BN_CTX_free(ctx_new);
519 * XXX This approach assumes that the external representation of curves
520 * over the same field type is the same.
522 if (!a->meth->group_get_curve(a, a1, a2, a3, ctx) ||
523 !b->meth->group_get_curve(b, b1, b2, b3, ctx))
526 if (r || BN_cmp(a1, b1) || BN_cmp(a2, b2) || BN_cmp(a3, b3))
529 /* XXX EC_POINT_cmp() assumes that the methods are equal */
530 if (r || EC_POINT_cmp(a, EC_GROUP_get0_generator(a),
531 EC_GROUP_get0_generator(b), ctx))
535 const BIGNUM *ao, *bo, *ac, *bc;
536 /* compare the order and cofactor */
537 ao = EC_GROUP_get0_order(a);
538 bo = EC_GROUP_get0_order(b);
539 ac = EC_GROUP_get0_cofactor(a);
540 bc = EC_GROUP_get0_cofactor(b);
541 if (ao == NULL || bo == NULL) {
543 BN_CTX_free(ctx_new);
546 if (BN_cmp(ao, bo) || BN_cmp(ac, bc))
551 BN_CTX_free(ctx_new);
556 /* functions for EC_POINT objects */
558 EC_POINT *EC_POINT_new(const EC_GROUP *group)
563 ECerr(EC_F_EC_POINT_NEW, ERR_R_PASSED_NULL_PARAMETER);
566 if (group->meth->point_init == NULL) {
567 ECerr(EC_F_EC_POINT_NEW, ERR_R_SHOULD_NOT_HAVE_BEEN_CALLED);
571 ret = OPENSSL_zalloc(sizeof(*ret));
573 ECerr(EC_F_EC_POINT_NEW, ERR_R_MALLOC_FAILURE);
577 ret->meth = group->meth;
578 ret->curve_name = group->curve_name;
580 if (!ret->meth->point_init(ret)) {
588 void EC_POINT_free(EC_POINT *point)
593 if (point->meth->point_finish != 0)
594 point->meth->point_finish(point);
598 void EC_POINT_clear_free(EC_POINT *point)
603 if (point->meth->point_clear_finish != 0)
604 point->meth->point_clear_finish(point);
605 else if (point->meth->point_finish != 0)
606 point->meth->point_finish(point);
607 OPENSSL_clear_free(point, sizeof(*point));
610 int EC_POINT_copy(EC_POINT *dest, const EC_POINT *src)
612 if (dest->meth->point_copy == 0) {
613 ECerr(EC_F_EC_POINT_COPY, ERR_R_SHOULD_NOT_HAVE_BEEN_CALLED);
616 if (dest->meth != src->meth
617 || (dest->curve_name != src->curve_name
618 && dest->curve_name != 0
619 && src->curve_name != 0)) {
620 ECerr(EC_F_EC_POINT_COPY, EC_R_INCOMPATIBLE_OBJECTS);
625 return dest->meth->point_copy(dest, src);
628 EC_POINT *EC_POINT_dup(const EC_POINT *a, const EC_GROUP *group)
636 t = EC_POINT_new(group);
639 r = EC_POINT_copy(t, a);
647 const EC_METHOD *EC_POINT_method_of(const EC_POINT *point)
652 int EC_POINT_set_to_infinity(const EC_GROUP *group, EC_POINT *point)
654 if (group->meth->point_set_to_infinity == 0) {
655 ECerr(EC_F_EC_POINT_SET_TO_INFINITY,
656 ERR_R_SHOULD_NOT_HAVE_BEEN_CALLED);
659 if (group->meth != point->meth) {
660 ECerr(EC_F_EC_POINT_SET_TO_INFINITY, EC_R_INCOMPATIBLE_OBJECTS);
663 return group->meth->point_set_to_infinity(group, point);
666 int EC_POINT_set_Jprojective_coordinates_GFp(const EC_GROUP *group,
667 EC_POINT *point, const BIGNUM *x,
668 const BIGNUM *y, const BIGNUM *z,
671 if (group->meth->point_set_Jprojective_coordinates_GFp == 0) {
672 ECerr(EC_F_EC_POINT_SET_JPROJECTIVE_COORDINATES_GFP,
673 ERR_R_SHOULD_NOT_HAVE_BEEN_CALLED);
676 if (!ec_point_is_compat(point, group)) {
677 ECerr(EC_F_EC_POINT_SET_JPROJECTIVE_COORDINATES_GFP,
678 EC_R_INCOMPATIBLE_OBJECTS);
681 return group->meth->point_set_Jprojective_coordinates_GFp(group, point, x,
685 int EC_POINT_get_Jprojective_coordinates_GFp(const EC_GROUP *group,
686 const EC_POINT *point, BIGNUM *x,
687 BIGNUM *y, BIGNUM *z,
690 if (group->meth->point_get_Jprojective_coordinates_GFp == 0) {
691 ECerr(EC_F_EC_POINT_GET_JPROJECTIVE_COORDINATES_GFP,
692 ERR_R_SHOULD_NOT_HAVE_BEEN_CALLED);
695 if (!ec_point_is_compat(point, group)) {
696 ECerr(EC_F_EC_POINT_GET_JPROJECTIVE_COORDINATES_GFP,
697 EC_R_INCOMPATIBLE_OBJECTS);
700 return group->meth->point_get_Jprojective_coordinates_GFp(group, point, x,
704 int EC_POINT_set_affine_coordinates(const EC_GROUP *group, EC_POINT *point,
705 const BIGNUM *x, const BIGNUM *y,
708 if (group->meth->point_set_affine_coordinates == NULL) {
709 ECerr(EC_F_EC_POINT_SET_AFFINE_COORDINATES,
710 ERR_R_SHOULD_NOT_HAVE_BEEN_CALLED);
713 if (!ec_point_is_compat(point, group)) {
714 ECerr(EC_F_EC_POINT_SET_AFFINE_COORDINATES, EC_R_INCOMPATIBLE_OBJECTS);
717 if (!group->meth->point_set_affine_coordinates(group, point, x, y, ctx))
720 if (EC_POINT_is_on_curve(group, point, ctx) <= 0) {
721 ECerr(EC_F_EC_POINT_SET_AFFINE_COORDINATES, EC_R_POINT_IS_NOT_ON_CURVE);
727 int EC_POINT_set_affine_coordinates_GFp(const EC_GROUP *group,
728 EC_POINT *point, const BIGNUM *x,
729 const BIGNUM *y, BN_CTX *ctx)
731 return EC_POINT_set_affine_coordinates(group, point, x, y, ctx);
734 #ifndef OPENSSL_NO_EC2M
735 int EC_POINT_set_affine_coordinates_GF2m(const EC_GROUP *group,
736 EC_POINT *point, const BIGNUM *x,
737 const BIGNUM *y, BN_CTX *ctx)
739 return EC_POINT_set_affine_coordinates(group, point, x, y, ctx);
743 int EC_POINT_get_affine_coordinates(const EC_GROUP *group,
744 const EC_POINT *point, BIGNUM *x, BIGNUM *y,
747 if (group->meth->point_get_affine_coordinates == NULL) {
748 ECerr(EC_F_EC_POINT_GET_AFFINE_COORDINATES,
749 ERR_R_SHOULD_NOT_HAVE_BEEN_CALLED);
752 if (!ec_point_is_compat(point, group)) {
753 ECerr(EC_F_EC_POINT_GET_AFFINE_COORDINATES, EC_R_INCOMPATIBLE_OBJECTS);
756 return group->meth->point_get_affine_coordinates(group, point, x, y, ctx);
759 int EC_POINT_get_affine_coordinates_GFp(const EC_GROUP *group,
760 const EC_POINT *point, BIGNUM *x,
761 BIGNUM *y, BN_CTX *ctx)
763 return EC_POINT_get_affine_coordinates(group, point, x, y, ctx);
766 #ifndef OPENSSL_NO_EC2M
767 int EC_POINT_get_affine_coordinates_GF2m(const EC_GROUP *group,
768 const EC_POINT *point, BIGNUM *x,
769 BIGNUM *y, BN_CTX *ctx)
771 return EC_POINT_get_affine_coordinates(group, point, x, y, ctx);
775 int EC_POINT_add(const EC_GROUP *group, EC_POINT *r, const EC_POINT *a,
776 const EC_POINT *b, BN_CTX *ctx)
778 if (group->meth->add == 0) {
779 ECerr(EC_F_EC_POINT_ADD, ERR_R_SHOULD_NOT_HAVE_BEEN_CALLED);
782 if (!ec_point_is_compat(r, group) || !ec_point_is_compat(a, group)
783 || !ec_point_is_compat(b, group)) {
784 ECerr(EC_F_EC_POINT_ADD, EC_R_INCOMPATIBLE_OBJECTS);
787 return group->meth->add(group, r, a, b, ctx);
790 int EC_POINT_dbl(const EC_GROUP *group, EC_POINT *r, const EC_POINT *a,
793 if (group->meth->dbl == 0) {
794 ECerr(EC_F_EC_POINT_DBL, ERR_R_SHOULD_NOT_HAVE_BEEN_CALLED);
797 if (!ec_point_is_compat(r, group) || !ec_point_is_compat(a, group)) {
798 ECerr(EC_F_EC_POINT_DBL, EC_R_INCOMPATIBLE_OBJECTS);
801 return group->meth->dbl(group, r, a, ctx);
804 int EC_POINT_invert(const EC_GROUP *group, EC_POINT *a, BN_CTX *ctx)
806 if (group->meth->invert == 0) {
807 ECerr(EC_F_EC_POINT_INVERT, ERR_R_SHOULD_NOT_HAVE_BEEN_CALLED);
810 if (!ec_point_is_compat(a, group)) {
811 ECerr(EC_F_EC_POINT_INVERT, EC_R_INCOMPATIBLE_OBJECTS);
814 return group->meth->invert(group, a, ctx);
817 int EC_POINT_is_at_infinity(const EC_GROUP *group, const EC_POINT *point)
819 if (group->meth->is_at_infinity == 0) {
820 ECerr(EC_F_EC_POINT_IS_AT_INFINITY,
821 ERR_R_SHOULD_NOT_HAVE_BEEN_CALLED);
824 if (!ec_point_is_compat(point, group)) {
825 ECerr(EC_F_EC_POINT_IS_AT_INFINITY, EC_R_INCOMPATIBLE_OBJECTS);
828 return group->meth->is_at_infinity(group, point);
832 * Check whether an EC_POINT is on the curve or not. Note that the return
833 * value for this function should NOT be treated as a boolean. Return values:
834 * 1: The point is on the curve
835 * 0: The point is not on the curve
836 * -1: An error occurred
838 int EC_POINT_is_on_curve(const EC_GROUP *group, const EC_POINT *point,
841 if (group->meth->is_on_curve == 0) {
842 ECerr(EC_F_EC_POINT_IS_ON_CURVE, ERR_R_SHOULD_NOT_HAVE_BEEN_CALLED);
845 if (!ec_point_is_compat(point, group)) {
846 ECerr(EC_F_EC_POINT_IS_ON_CURVE, EC_R_INCOMPATIBLE_OBJECTS);
849 return group->meth->is_on_curve(group, point, ctx);
852 int EC_POINT_cmp(const EC_GROUP *group, const EC_POINT *a, const EC_POINT *b,
855 if (group->meth->point_cmp == 0) {
856 ECerr(EC_F_EC_POINT_CMP, ERR_R_SHOULD_NOT_HAVE_BEEN_CALLED);
859 if (!ec_point_is_compat(a, group) || !ec_point_is_compat(b, group)) {
860 ECerr(EC_F_EC_POINT_CMP, EC_R_INCOMPATIBLE_OBJECTS);
863 return group->meth->point_cmp(group, a, b, ctx);
866 int EC_POINT_make_affine(const EC_GROUP *group, EC_POINT *point, BN_CTX *ctx)
868 if (group->meth->make_affine == 0) {
869 ECerr(EC_F_EC_POINT_MAKE_AFFINE, ERR_R_SHOULD_NOT_HAVE_BEEN_CALLED);
872 if (!ec_point_is_compat(point, group)) {
873 ECerr(EC_F_EC_POINT_MAKE_AFFINE, EC_R_INCOMPATIBLE_OBJECTS);
876 return group->meth->make_affine(group, point, ctx);
879 int EC_POINTs_make_affine(const EC_GROUP *group, size_t num,
880 EC_POINT *points[], BN_CTX *ctx)
884 if (group->meth->points_make_affine == 0) {
885 ECerr(EC_F_EC_POINTS_MAKE_AFFINE, ERR_R_SHOULD_NOT_HAVE_BEEN_CALLED);
888 for (i = 0; i < num; i++) {
889 if (!ec_point_is_compat(points[i], group)) {
890 ECerr(EC_F_EC_POINTS_MAKE_AFFINE, EC_R_INCOMPATIBLE_OBJECTS);
894 return group->meth->points_make_affine(group, num, points, ctx);
898 * Functions for point multiplication. If group->meth->mul is 0, we use the
899 * wNAF-based implementations in ec_mult.c; otherwise we dispatch through
903 int EC_POINTs_mul(const EC_GROUP *group, EC_POINT *r, const BIGNUM *scalar,
904 size_t num, const EC_POINT *points[],
905 const BIGNUM *scalars[], BN_CTX *ctx)
909 BN_CTX *new_ctx = NULL;
911 if ((scalar == NULL) && (num == 0)) {
912 return EC_POINT_set_to_infinity(group, r);
915 if (!ec_point_is_compat(r, group)) {
916 ECerr(EC_F_EC_POINTS_MUL, EC_R_INCOMPATIBLE_OBJECTS);
919 for (i = 0; i < num; i++) {
920 if (!ec_point_is_compat(points[i], group)) {
921 ECerr(EC_F_EC_POINTS_MUL, EC_R_INCOMPATIBLE_OBJECTS);
926 if (ctx == NULL && (ctx = new_ctx = BN_CTX_secure_new()) == NULL) {
927 ECerr(EC_F_EC_POINTS_MUL, ERR_R_INTERNAL_ERROR);
931 if (group->meth->mul != NULL)
932 ret = group->meth->mul(group, r, scalar, num, points, scalars, ctx);
935 ret = ec_wNAF_mul(group, r, scalar, num, points, scalars, ctx);
937 BN_CTX_free(new_ctx);
941 int EC_POINT_mul(const EC_GROUP *group, EC_POINT *r, const BIGNUM *g_scalar,
942 const EC_POINT *point, const BIGNUM *p_scalar, BN_CTX *ctx)
944 /* just a convenient interface to EC_POINTs_mul() */
946 const EC_POINT *points[1];
947 const BIGNUM *scalars[1];
950 scalars[0] = p_scalar;
952 return EC_POINTs_mul(group, r, g_scalar,
954 && p_scalar != NULL), points, scalars, ctx);
957 int EC_GROUP_precompute_mult(EC_GROUP *group, BN_CTX *ctx)
959 if (group->meth->mul == 0)
961 return ec_wNAF_precompute_mult(group, ctx);
963 if (group->meth->precompute_mult != 0)
964 return group->meth->precompute_mult(group, ctx);
966 return 1; /* nothing to do, so report success */
969 int EC_GROUP_have_precompute_mult(const EC_GROUP *group)
971 if (group->meth->mul == 0)
973 return ec_wNAF_have_precompute_mult(group);
975 if (group->meth->have_precompute_mult != 0)
976 return group->meth->have_precompute_mult(group);
978 return 0; /* cannot tell whether precomputation has
983 * ec_precompute_mont_data sets |group->mont_data| from |group->order| and
984 * returns one on success. On error it returns zero.
986 static int ec_precompute_mont_data(EC_GROUP *group)
988 BN_CTX *ctx = BN_CTX_new();
991 BN_MONT_CTX_free(group->mont_data);
992 group->mont_data = NULL;
997 group->mont_data = BN_MONT_CTX_new();
998 if (group->mont_data == NULL)
1001 if (!BN_MONT_CTX_set(group->mont_data, group->order, ctx)) {
1002 BN_MONT_CTX_free(group->mont_data);
1003 group->mont_data = NULL;
1015 int EC_KEY_set_ex_data(EC_KEY *key, int idx, void *arg)
1017 return CRYPTO_set_ex_data(&key->ex_data, idx, arg);
1020 void *EC_KEY_get_ex_data(const EC_KEY *key, int idx)
1022 return CRYPTO_get_ex_data(&key->ex_data, idx);
1025 int ec_group_simple_order_bits(const EC_GROUP *group)
1027 if (group->order == NULL)
1029 return BN_num_bits(group->order);
1032 static int ec_field_inverse_mod_ord(const EC_GROUP *group, BIGNUM *r,
1033 const BIGNUM *x, BN_CTX *ctx)
1036 BN_CTX *new_ctx = NULL;
1039 if (group->mont_data == NULL)
1042 if (ctx == NULL && (ctx = new_ctx = BN_CTX_secure_new()) == NULL)
1046 if ((e = BN_CTX_get(ctx)) == NULL)
1050 * We want inverse in constant time, therefore we utilize the fact
1051 * order must be prime and use Fermats Little Theorem instead.
1053 if (!BN_set_word(e, 2))
1055 if (!BN_sub(e, group->order, e))
1058 * Exponent e is public.
1059 * No need for scatter-gather or BN_FLG_CONSTTIME.
1061 if (!BN_mod_exp_mont(r, x, e, group->order, ctx, group->mont_data))
1069 BN_CTX_free(new_ctx);
1074 * Default behavior, if group->meth->field_inverse_mod_ord is NULL:
1075 * - When group->order is even, this function returns an error.
1076 * - When group->order is otherwise composite, the correctness
1077 * of the output is not guaranteed.
1078 * - When x is outside the range [1, group->order), the correctness
1079 * of the output is not guaranteed.
1080 * - Otherwise, this function returns the multiplicative inverse in the
1081 * range [1, group->order).
1083 * EC_METHODs must implement their own field_inverse_mod_ord for
1084 * other functionality.
1086 int ec_group_do_inverse_ord(const EC_GROUP *group, BIGNUM *res,
1087 const BIGNUM *x, BN_CTX *ctx)
1089 if (group->meth->field_inverse_mod_ord != NULL)
1090 return group->meth->field_inverse_mod_ord(group, res, x, ctx);
1092 return ec_field_inverse_mod_ord(group, res, x, ctx);
1096 * Coordinate blinding for EC_POINT.
1098 * The underlying EC_METHOD can optionally implement this function:
1099 * underlying implementations should return 0 on errors, or 1 on
1102 * This wrapper returns 1 in case the underlying EC_METHOD does not
1103 * support coordinate blinding.
1105 int ec_point_blind_coordinates(const EC_GROUP *group, EC_POINT *p, BN_CTX *ctx)
1107 if (group->meth->blind_coordinates == NULL)
1108 return 1; /* ignore if not implemented */
1110 return group->meth->blind_coordinates(group, p, ctx);