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 Apache License 2.0 (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);
291 /* The cofactor is an optional field, so it should be able to be NULL. */
292 if (cofactor != NULL) {
293 if (!BN_copy(group->cofactor, cofactor))
296 BN_zero(group->cofactor);
299 * Some groups have an order with
300 * factors of two, which makes the Montgomery setup fail.
301 * |group->mont_data| will be NULL in this case.
303 if (BN_is_odd(group->order)) {
304 return ec_precompute_mont_data(group);
307 BN_MONT_CTX_free(group->mont_data);
308 group->mont_data = NULL;
312 const EC_POINT *EC_GROUP_get0_generator(const EC_GROUP *group)
314 return group->generator;
317 BN_MONT_CTX *EC_GROUP_get_mont_data(const EC_GROUP *group)
319 return group->mont_data;
322 int EC_GROUP_get_order(const EC_GROUP *group, BIGNUM *order, BN_CTX *ctx)
324 if (group->order == NULL)
326 if (!BN_copy(order, group->order))
329 return !BN_is_zero(order);
332 const BIGNUM *EC_GROUP_get0_order(const EC_GROUP *group)
337 int EC_GROUP_order_bits(const EC_GROUP *group)
339 return group->meth->group_order_bits(group);
342 int EC_GROUP_get_cofactor(const EC_GROUP *group, BIGNUM *cofactor,
346 if (group->cofactor == NULL)
348 if (!BN_copy(cofactor, group->cofactor))
351 return !BN_is_zero(group->cofactor);
354 const BIGNUM *EC_GROUP_get0_cofactor(const EC_GROUP *group)
356 return group->cofactor;
359 void EC_GROUP_set_curve_name(EC_GROUP *group, int nid)
361 group->curve_name = nid;
364 int EC_GROUP_get_curve_name(const EC_GROUP *group)
366 return group->curve_name;
369 const BIGNUM *EC_GROUP_get0_field(const EC_GROUP *group)
374 void EC_GROUP_set_asn1_flag(EC_GROUP *group, int flag)
376 group->asn1_flag = flag;
379 int EC_GROUP_get_asn1_flag(const EC_GROUP *group)
381 return group->asn1_flag;
384 void EC_GROUP_set_point_conversion_form(EC_GROUP *group,
385 point_conversion_form_t form)
387 group->asn1_form = form;
390 point_conversion_form_t EC_GROUP_get_point_conversion_form(const EC_GROUP
393 return group->asn1_form;
396 size_t EC_GROUP_set_seed(EC_GROUP *group, const unsigned char *p, size_t len)
398 OPENSSL_free(group->seed);
405 if ((group->seed = OPENSSL_malloc(len)) == NULL) {
406 ECerr(EC_F_EC_GROUP_SET_SEED, ERR_R_MALLOC_FAILURE);
409 memcpy(group->seed, p, len);
410 group->seed_len = len;
415 unsigned char *EC_GROUP_get0_seed(const EC_GROUP *group)
420 size_t EC_GROUP_get_seed_len(const EC_GROUP *group)
422 return group->seed_len;
425 int EC_GROUP_set_curve(EC_GROUP *group, const BIGNUM *p, const BIGNUM *a,
426 const BIGNUM *b, BN_CTX *ctx)
428 if (group->meth->group_set_curve == 0) {
429 ECerr(EC_F_EC_GROUP_SET_CURVE, ERR_R_SHOULD_NOT_HAVE_BEEN_CALLED);
432 return group->meth->group_set_curve(group, p, a, b, ctx);
435 int EC_GROUP_get_curve(const EC_GROUP *group, BIGNUM *p, BIGNUM *a, BIGNUM *b,
438 if (group->meth->group_get_curve == NULL) {
439 ECerr(EC_F_EC_GROUP_GET_CURVE, ERR_R_SHOULD_NOT_HAVE_BEEN_CALLED);
442 return group->meth->group_get_curve(group, p, a, b, ctx);
446 int EC_GROUP_set_curve_GFp(EC_GROUP *group, const BIGNUM *p, const BIGNUM *a,
447 const BIGNUM *b, BN_CTX *ctx)
449 return EC_GROUP_set_curve(group, p, a, b, ctx);
452 int EC_GROUP_get_curve_GFp(const EC_GROUP *group, BIGNUM *p, BIGNUM *a,
453 BIGNUM *b, BN_CTX *ctx)
455 return EC_GROUP_get_curve(group, p, a, b, ctx);
458 # ifndef OPENSSL_NO_EC2M
459 int EC_GROUP_set_curve_GF2m(EC_GROUP *group, const BIGNUM *p, const BIGNUM *a,
460 const BIGNUM *b, BN_CTX *ctx)
462 return EC_GROUP_set_curve(group, p, a, b, ctx);
465 int EC_GROUP_get_curve_GF2m(const EC_GROUP *group, BIGNUM *p, BIGNUM *a,
466 BIGNUM *b, BN_CTX *ctx)
468 return EC_GROUP_get_curve(group, p, a, b, ctx);
473 int EC_GROUP_get_degree(const EC_GROUP *group)
475 if (group->meth->group_get_degree == 0) {
476 ECerr(EC_F_EC_GROUP_GET_DEGREE, ERR_R_SHOULD_NOT_HAVE_BEEN_CALLED);
479 return group->meth->group_get_degree(group);
482 int EC_GROUP_check_discriminant(const EC_GROUP *group, BN_CTX *ctx)
484 if (group->meth->group_check_discriminant == 0) {
485 ECerr(EC_F_EC_GROUP_CHECK_DISCRIMINANT,
486 ERR_R_SHOULD_NOT_HAVE_BEEN_CALLED);
489 return group->meth->group_check_discriminant(group, ctx);
492 int EC_GROUP_cmp(const EC_GROUP *a, const EC_GROUP *b, BN_CTX *ctx)
495 BIGNUM *a1, *a2, *a3, *b1, *b2, *b3;
496 BN_CTX *ctx_new = NULL;
498 /* compare the field types */
499 if (EC_METHOD_get_field_type(EC_GROUP_method_of(a)) !=
500 EC_METHOD_get_field_type(EC_GROUP_method_of(b)))
502 /* compare the curve name (if present in both) */
503 if (EC_GROUP_get_curve_name(a) && EC_GROUP_get_curve_name(b) &&
504 EC_GROUP_get_curve_name(a) != EC_GROUP_get_curve_name(b))
506 if (a->meth->flags & EC_FLAGS_CUSTOM_CURVE)
510 ctx_new = ctx = BN_CTX_new();
515 a1 = BN_CTX_get(ctx);
516 a2 = BN_CTX_get(ctx);
517 a3 = BN_CTX_get(ctx);
518 b1 = BN_CTX_get(ctx);
519 b2 = BN_CTX_get(ctx);
520 b3 = BN_CTX_get(ctx);
523 BN_CTX_free(ctx_new);
528 * XXX This approach assumes that the external representation of curves
529 * over the same field type is the same.
531 if (!a->meth->group_get_curve(a, a1, a2, a3, ctx) ||
532 !b->meth->group_get_curve(b, b1, b2, b3, ctx))
535 /* return 1 if the curve parameters are different */
536 if (r || BN_cmp(a1, b1) != 0 || BN_cmp(a2, b2) != 0 || BN_cmp(a3, b3) != 0)
539 /* XXX EC_POINT_cmp() assumes that the methods are equal */
540 /* return 1 if the generators are different */
541 if (r || EC_POINT_cmp(a, EC_GROUP_get0_generator(a),
542 EC_GROUP_get0_generator(b), ctx) != 0)
546 const BIGNUM *ao, *bo, *ac, *bc;
547 /* compare the orders */
548 ao = EC_GROUP_get0_order(a);
549 bo = EC_GROUP_get0_order(b);
550 if (ao == NULL || bo == NULL) {
551 /* return an error if either order is NULL */
555 if (BN_cmp(ao, bo) != 0) {
556 /* return 1 if orders are different */
561 * It gets here if the curve parameters and generator matched.
562 * Now check the optional cofactors (if both are present).
564 ac = EC_GROUP_get0_cofactor(a);
565 bc = EC_GROUP_get0_cofactor(b);
566 /* Returns 1 (mismatch) if both cofactors are specified and different */
567 if (!BN_is_zero(ac) && !BN_is_zero(bc) && BN_cmp(ac, bc) != 0)
569 /* Returns 0 if the parameters matched */
573 BN_CTX_free(ctx_new);
578 /* functions for EC_POINT objects */
580 EC_POINT *EC_POINT_new(const EC_GROUP *group)
585 ECerr(EC_F_EC_POINT_NEW, ERR_R_PASSED_NULL_PARAMETER);
588 if (group->meth->point_init == NULL) {
589 ECerr(EC_F_EC_POINT_NEW, ERR_R_SHOULD_NOT_HAVE_BEEN_CALLED);
593 ret = OPENSSL_zalloc(sizeof(*ret));
595 ECerr(EC_F_EC_POINT_NEW, ERR_R_MALLOC_FAILURE);
599 ret->meth = group->meth;
600 ret->curve_name = group->curve_name;
602 if (!ret->meth->point_init(ret)) {
610 void EC_POINT_free(EC_POINT *point)
615 if (point->meth->point_finish != 0)
616 point->meth->point_finish(point);
620 void EC_POINT_clear_free(EC_POINT *point)
625 if (point->meth->point_clear_finish != 0)
626 point->meth->point_clear_finish(point);
627 else if (point->meth->point_finish != 0)
628 point->meth->point_finish(point);
629 OPENSSL_clear_free(point, sizeof(*point));
632 int EC_POINT_copy(EC_POINT *dest, const EC_POINT *src)
634 if (dest->meth->point_copy == 0) {
635 ECerr(EC_F_EC_POINT_COPY, ERR_R_SHOULD_NOT_HAVE_BEEN_CALLED);
638 if (dest->meth != src->meth
639 || (dest->curve_name != src->curve_name
640 && dest->curve_name != 0
641 && src->curve_name != 0)) {
642 ECerr(EC_F_EC_POINT_COPY, EC_R_INCOMPATIBLE_OBJECTS);
647 return dest->meth->point_copy(dest, src);
650 EC_POINT *EC_POINT_dup(const EC_POINT *a, const EC_GROUP *group)
658 t = EC_POINT_new(group);
661 r = EC_POINT_copy(t, a);
669 const EC_METHOD *EC_POINT_method_of(const EC_POINT *point)
674 int EC_POINT_set_to_infinity(const EC_GROUP *group, EC_POINT *point)
676 if (group->meth->point_set_to_infinity == 0) {
677 ECerr(EC_F_EC_POINT_SET_TO_INFINITY,
678 ERR_R_SHOULD_NOT_HAVE_BEEN_CALLED);
681 if (group->meth != point->meth) {
682 ECerr(EC_F_EC_POINT_SET_TO_INFINITY, EC_R_INCOMPATIBLE_OBJECTS);
685 return group->meth->point_set_to_infinity(group, point);
688 int EC_POINT_set_Jprojective_coordinates_GFp(const EC_GROUP *group,
689 EC_POINT *point, const BIGNUM *x,
690 const BIGNUM *y, const BIGNUM *z,
693 if (group->meth->point_set_Jprojective_coordinates_GFp == 0) {
694 ECerr(EC_F_EC_POINT_SET_JPROJECTIVE_COORDINATES_GFP,
695 ERR_R_SHOULD_NOT_HAVE_BEEN_CALLED);
698 if (!ec_point_is_compat(point, group)) {
699 ECerr(EC_F_EC_POINT_SET_JPROJECTIVE_COORDINATES_GFP,
700 EC_R_INCOMPATIBLE_OBJECTS);
703 return group->meth->point_set_Jprojective_coordinates_GFp(group, point, x,
707 int EC_POINT_get_Jprojective_coordinates_GFp(const EC_GROUP *group,
708 const EC_POINT *point, BIGNUM *x,
709 BIGNUM *y, BIGNUM *z,
712 if (group->meth->point_get_Jprojective_coordinates_GFp == 0) {
713 ECerr(EC_F_EC_POINT_GET_JPROJECTIVE_COORDINATES_GFP,
714 ERR_R_SHOULD_NOT_HAVE_BEEN_CALLED);
717 if (!ec_point_is_compat(point, group)) {
718 ECerr(EC_F_EC_POINT_GET_JPROJECTIVE_COORDINATES_GFP,
719 EC_R_INCOMPATIBLE_OBJECTS);
722 return group->meth->point_get_Jprojective_coordinates_GFp(group, point, x,
726 int EC_POINT_set_affine_coordinates(const EC_GROUP *group, EC_POINT *point,
727 const BIGNUM *x, const BIGNUM *y,
730 if (group->meth->point_set_affine_coordinates == NULL) {
731 ECerr(EC_F_EC_POINT_SET_AFFINE_COORDINATES,
732 ERR_R_SHOULD_NOT_HAVE_BEEN_CALLED);
735 if (!ec_point_is_compat(point, group)) {
736 ECerr(EC_F_EC_POINT_SET_AFFINE_COORDINATES, EC_R_INCOMPATIBLE_OBJECTS);
739 if (!group->meth->point_set_affine_coordinates(group, point, x, y, ctx))
742 if (EC_POINT_is_on_curve(group, point, ctx) <= 0) {
743 ECerr(EC_F_EC_POINT_SET_AFFINE_COORDINATES, EC_R_POINT_IS_NOT_ON_CURVE);
750 int EC_POINT_set_affine_coordinates_GFp(const EC_GROUP *group,
751 EC_POINT *point, const BIGNUM *x,
752 const BIGNUM *y, BN_CTX *ctx)
754 return EC_POINT_set_affine_coordinates(group, point, x, y, ctx);
757 # ifndef OPENSSL_NO_EC2M
758 int EC_POINT_set_affine_coordinates_GF2m(const EC_GROUP *group,
759 EC_POINT *point, const BIGNUM *x,
760 const BIGNUM *y, BN_CTX *ctx)
762 return EC_POINT_set_affine_coordinates(group, point, x, y, ctx);
767 int EC_POINT_get_affine_coordinates(const EC_GROUP *group,
768 const EC_POINT *point, BIGNUM *x, BIGNUM *y,
771 if (group->meth->point_get_affine_coordinates == NULL) {
772 ECerr(EC_F_EC_POINT_GET_AFFINE_COORDINATES,
773 ERR_R_SHOULD_NOT_HAVE_BEEN_CALLED);
776 if (!ec_point_is_compat(point, group)) {
777 ECerr(EC_F_EC_POINT_GET_AFFINE_COORDINATES, EC_R_INCOMPATIBLE_OBJECTS);
780 if (EC_POINT_is_at_infinity(group, point)) {
781 ECerr(EC_F_EC_POINT_GET_AFFINE_COORDINATES, EC_R_POINT_AT_INFINITY);
784 return group->meth->point_get_affine_coordinates(group, point, x, y, ctx);
788 int EC_POINT_get_affine_coordinates_GFp(const EC_GROUP *group,
789 const EC_POINT *point, BIGNUM *x,
790 BIGNUM *y, BN_CTX *ctx)
792 return EC_POINT_get_affine_coordinates(group, point, x, y, ctx);
795 # ifndef OPENSSL_NO_EC2M
796 int EC_POINT_get_affine_coordinates_GF2m(const EC_GROUP *group,
797 const EC_POINT *point, BIGNUM *x,
798 BIGNUM *y, BN_CTX *ctx)
800 return EC_POINT_get_affine_coordinates(group, point, x, y, ctx);
805 int EC_POINT_add(const EC_GROUP *group, EC_POINT *r, const EC_POINT *a,
806 const EC_POINT *b, BN_CTX *ctx)
808 if (group->meth->add == 0) {
809 ECerr(EC_F_EC_POINT_ADD, ERR_R_SHOULD_NOT_HAVE_BEEN_CALLED);
812 if (!ec_point_is_compat(r, group) || !ec_point_is_compat(a, group)
813 || !ec_point_is_compat(b, group)) {
814 ECerr(EC_F_EC_POINT_ADD, EC_R_INCOMPATIBLE_OBJECTS);
817 return group->meth->add(group, r, a, b, ctx);
820 int EC_POINT_dbl(const EC_GROUP *group, EC_POINT *r, const EC_POINT *a,
823 if (group->meth->dbl == 0) {
824 ECerr(EC_F_EC_POINT_DBL, ERR_R_SHOULD_NOT_HAVE_BEEN_CALLED);
827 if (!ec_point_is_compat(r, group) || !ec_point_is_compat(a, group)) {
828 ECerr(EC_F_EC_POINT_DBL, EC_R_INCOMPATIBLE_OBJECTS);
831 return group->meth->dbl(group, r, a, ctx);
834 int EC_POINT_invert(const EC_GROUP *group, EC_POINT *a, BN_CTX *ctx)
836 if (group->meth->invert == 0) {
837 ECerr(EC_F_EC_POINT_INVERT, ERR_R_SHOULD_NOT_HAVE_BEEN_CALLED);
840 if (!ec_point_is_compat(a, group)) {
841 ECerr(EC_F_EC_POINT_INVERT, EC_R_INCOMPATIBLE_OBJECTS);
844 return group->meth->invert(group, a, ctx);
847 int EC_POINT_is_at_infinity(const EC_GROUP *group, const EC_POINT *point)
849 if (group->meth->is_at_infinity == 0) {
850 ECerr(EC_F_EC_POINT_IS_AT_INFINITY,
851 ERR_R_SHOULD_NOT_HAVE_BEEN_CALLED);
854 if (!ec_point_is_compat(point, group)) {
855 ECerr(EC_F_EC_POINT_IS_AT_INFINITY, EC_R_INCOMPATIBLE_OBJECTS);
858 return group->meth->is_at_infinity(group, point);
862 * Check whether an EC_POINT is on the curve or not. Note that the return
863 * value for this function should NOT be treated as a boolean. Return values:
864 * 1: The point is on the curve
865 * 0: The point is not on the curve
866 * -1: An error occurred
868 int EC_POINT_is_on_curve(const EC_GROUP *group, const EC_POINT *point,
871 if (group->meth->is_on_curve == 0) {
872 ECerr(EC_F_EC_POINT_IS_ON_CURVE, ERR_R_SHOULD_NOT_HAVE_BEEN_CALLED);
875 if (!ec_point_is_compat(point, group)) {
876 ECerr(EC_F_EC_POINT_IS_ON_CURVE, EC_R_INCOMPATIBLE_OBJECTS);
879 return group->meth->is_on_curve(group, point, ctx);
882 int EC_POINT_cmp(const EC_GROUP *group, const EC_POINT *a, const EC_POINT *b,
885 if (group->meth->point_cmp == 0) {
886 ECerr(EC_F_EC_POINT_CMP, ERR_R_SHOULD_NOT_HAVE_BEEN_CALLED);
889 if (!ec_point_is_compat(a, group) || !ec_point_is_compat(b, group)) {
890 ECerr(EC_F_EC_POINT_CMP, EC_R_INCOMPATIBLE_OBJECTS);
893 return group->meth->point_cmp(group, a, b, ctx);
896 int EC_POINT_make_affine(const EC_GROUP *group, EC_POINT *point, BN_CTX *ctx)
898 if (group->meth->make_affine == 0) {
899 ECerr(EC_F_EC_POINT_MAKE_AFFINE, ERR_R_SHOULD_NOT_HAVE_BEEN_CALLED);
902 if (!ec_point_is_compat(point, group)) {
903 ECerr(EC_F_EC_POINT_MAKE_AFFINE, EC_R_INCOMPATIBLE_OBJECTS);
906 return group->meth->make_affine(group, point, ctx);
909 int EC_POINTs_make_affine(const EC_GROUP *group, size_t num,
910 EC_POINT *points[], BN_CTX *ctx)
914 if (group->meth->points_make_affine == 0) {
915 ECerr(EC_F_EC_POINTS_MAKE_AFFINE, ERR_R_SHOULD_NOT_HAVE_BEEN_CALLED);
918 for (i = 0; i < num; i++) {
919 if (!ec_point_is_compat(points[i], group)) {
920 ECerr(EC_F_EC_POINTS_MAKE_AFFINE, EC_R_INCOMPATIBLE_OBJECTS);
924 return group->meth->points_make_affine(group, num, points, ctx);
928 * Functions for point multiplication. If group->meth->mul is 0, we use the
929 * wNAF-based implementations in ec_mult.c; otherwise we dispatch through
933 int EC_POINTs_mul(const EC_GROUP *group, EC_POINT *r, const BIGNUM *scalar,
934 size_t num, const EC_POINT *points[],
935 const BIGNUM *scalars[], BN_CTX *ctx)
939 BN_CTX *new_ctx = NULL;
941 if ((scalar == NULL) && (num == 0)) {
942 return EC_POINT_set_to_infinity(group, r);
945 if (!ec_point_is_compat(r, group)) {
946 ECerr(EC_F_EC_POINTS_MUL, EC_R_INCOMPATIBLE_OBJECTS);
949 for (i = 0; i < num; i++) {
950 if (!ec_point_is_compat(points[i], group)) {
951 ECerr(EC_F_EC_POINTS_MUL, EC_R_INCOMPATIBLE_OBJECTS);
956 if (ctx == NULL && (ctx = new_ctx = BN_CTX_secure_new()) == NULL) {
957 ECerr(EC_F_EC_POINTS_MUL, ERR_R_INTERNAL_ERROR);
961 if (group->meth->mul != NULL)
962 ret = group->meth->mul(group, r, scalar, num, points, scalars, ctx);
965 ret = ec_wNAF_mul(group, r, scalar, num, points, scalars, ctx);
967 BN_CTX_free(new_ctx);
971 int EC_POINT_mul(const EC_GROUP *group, EC_POINT *r, const BIGNUM *g_scalar,
972 const EC_POINT *point, const BIGNUM *p_scalar, BN_CTX *ctx)
974 /* just a convenient interface to EC_POINTs_mul() */
976 const EC_POINT *points[1];
977 const BIGNUM *scalars[1];
980 scalars[0] = p_scalar;
982 return EC_POINTs_mul(group, r, g_scalar,
984 && p_scalar != NULL), points, scalars, ctx);
987 int EC_GROUP_precompute_mult(EC_GROUP *group, BN_CTX *ctx)
989 if (group->meth->mul == 0)
991 return ec_wNAF_precompute_mult(group, ctx);
993 if (group->meth->precompute_mult != 0)
994 return group->meth->precompute_mult(group, ctx);
996 return 1; /* nothing to do, so report success */
999 int EC_GROUP_have_precompute_mult(const EC_GROUP *group)
1001 if (group->meth->mul == 0)
1003 return ec_wNAF_have_precompute_mult(group);
1005 if (group->meth->have_precompute_mult != 0)
1006 return group->meth->have_precompute_mult(group);
1008 return 0; /* cannot tell whether precomputation has
1013 * ec_precompute_mont_data sets |group->mont_data| from |group->order| and
1014 * returns one on success. On error it returns zero.
1016 static int ec_precompute_mont_data(EC_GROUP *group)
1018 BN_CTX *ctx = BN_CTX_new();
1021 BN_MONT_CTX_free(group->mont_data);
1022 group->mont_data = NULL;
1027 group->mont_data = BN_MONT_CTX_new();
1028 if (group->mont_data == NULL)
1031 if (!BN_MONT_CTX_set(group->mont_data, group->order, ctx)) {
1032 BN_MONT_CTX_free(group->mont_data);
1033 group->mont_data = NULL;
1045 int EC_KEY_set_ex_data(EC_KEY *key, int idx, void *arg)
1047 return CRYPTO_set_ex_data(&key->ex_data, idx, arg);
1050 void *EC_KEY_get_ex_data(const EC_KEY *key, int idx)
1052 return CRYPTO_get_ex_data(&key->ex_data, idx);
1055 int ec_group_simple_order_bits(const EC_GROUP *group)
1057 if (group->order == NULL)
1059 return BN_num_bits(group->order);
1062 static int ec_field_inverse_mod_ord(const EC_GROUP *group, BIGNUM *r,
1063 const BIGNUM *x, BN_CTX *ctx)
1066 BN_CTX *new_ctx = NULL;
1069 if (group->mont_data == NULL)
1072 if (ctx == NULL && (ctx = new_ctx = BN_CTX_secure_new()) == NULL)
1076 if ((e = BN_CTX_get(ctx)) == NULL)
1080 * We want inverse in constant time, therefore we utilize the fact
1081 * order must be prime and use Fermats Little Theorem instead.
1083 if (!BN_set_word(e, 2))
1085 if (!BN_sub(e, group->order, e))
1088 * Exponent e is public.
1089 * No need for scatter-gather or BN_FLG_CONSTTIME.
1091 if (!BN_mod_exp_mont(r, x, e, group->order, ctx, group->mont_data))
1098 BN_CTX_free(new_ctx);
1103 * Default behavior, if group->meth->field_inverse_mod_ord is NULL:
1104 * - When group->order is even, this function returns an error.
1105 * - When group->order is otherwise composite, the correctness
1106 * of the output is not guaranteed.
1107 * - When x is outside the range [1, group->order), the correctness
1108 * of the output is not guaranteed.
1109 * - Otherwise, this function returns the multiplicative inverse in the
1110 * range [1, group->order).
1112 * EC_METHODs must implement their own field_inverse_mod_ord for
1113 * other functionality.
1115 int ec_group_do_inverse_ord(const EC_GROUP *group, BIGNUM *res,
1116 const BIGNUM *x, BN_CTX *ctx)
1118 if (group->meth->field_inverse_mod_ord != NULL)
1119 return group->meth->field_inverse_mod_ord(group, res, x, ctx);
1121 return ec_field_inverse_mod_ord(group, res, x, ctx);
1125 * Coordinate blinding for EC_POINT.
1127 * The underlying EC_METHOD can optionally implement this function:
1128 * underlying implementations should return 0 on errors, or 1 on
1131 * This wrapper returns 1 in case the underlying EC_METHOD does not
1132 * support coordinate blinding.
1134 int ec_point_blind_coordinates(const EC_GROUP *group, EC_POINT *p, BN_CTX *ctx)
1136 if (group->meth->blind_coordinates == NULL)
1137 return 1; /* ignore if not implemented */
1139 return group->meth->blind_coordinates(group, p, ctx);