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a0fda2cf2d
Expression '...' is always true. The 'b->init' variable is assigned values twice successively Reviewed-by: Kurt Roeckx <kurt@roeckx.be> Reviewed-by: Rich Salz <rsalz@openssl.org> (Merged from https://github.com/openssl/openssl/pull/4753)
743 lines
19 KiB
C
743 lines
19 KiB
C
/*
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* Copyright 2002-2016 The OpenSSL Project Authors. All Rights Reserved.
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* Copyright (c) 2002, Oracle and/or its affiliates. All rights reserved
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*
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* Licensed under the OpenSSL license (the "License"). You may not use
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* this file except in compliance with the License. You can obtain a copy
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* in the file LICENSE in the source distribution or at
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* https://www.openssl.org/source/license.html
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*/
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#include <openssl/err.h>
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#include "internal/bn_int.h"
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#include "ec_lcl.h"
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#ifndef OPENSSL_NO_EC2M
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const EC_METHOD *EC_GF2m_simple_method(void)
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{
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static const EC_METHOD ret = {
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EC_FLAGS_DEFAULT_OCT,
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NID_X9_62_characteristic_two_field,
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ec_GF2m_simple_group_init,
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ec_GF2m_simple_group_finish,
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ec_GF2m_simple_group_clear_finish,
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ec_GF2m_simple_group_copy,
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ec_GF2m_simple_group_set_curve,
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ec_GF2m_simple_group_get_curve,
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ec_GF2m_simple_group_get_degree,
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ec_group_simple_order_bits,
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ec_GF2m_simple_group_check_discriminant,
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ec_GF2m_simple_point_init,
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ec_GF2m_simple_point_finish,
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ec_GF2m_simple_point_clear_finish,
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ec_GF2m_simple_point_copy,
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ec_GF2m_simple_point_set_to_infinity,
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0 /* set_Jprojective_coordinates_GFp */ ,
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0 /* get_Jprojective_coordinates_GFp */ ,
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ec_GF2m_simple_point_set_affine_coordinates,
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ec_GF2m_simple_point_get_affine_coordinates,
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0, 0, 0,
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ec_GF2m_simple_add,
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ec_GF2m_simple_dbl,
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ec_GF2m_simple_invert,
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ec_GF2m_simple_is_at_infinity,
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ec_GF2m_simple_is_on_curve,
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ec_GF2m_simple_cmp,
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ec_GF2m_simple_make_affine,
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ec_GF2m_simple_points_make_affine,
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/*
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* the following three method functions are defined in ec2_mult.c
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*/
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ec_GF2m_simple_mul,
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ec_GF2m_precompute_mult,
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ec_GF2m_have_precompute_mult,
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ec_GF2m_simple_field_mul,
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ec_GF2m_simple_field_sqr,
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ec_GF2m_simple_field_div,
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0 /* field_encode */ ,
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0 /* field_decode */ ,
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0, /* field_set_to_one */
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ec_key_simple_priv2oct,
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ec_key_simple_oct2priv,
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0, /* set private */
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ec_key_simple_generate_key,
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ec_key_simple_check_key,
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ec_key_simple_generate_public_key,
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0, /* keycopy */
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0, /* keyfinish */
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ecdh_simple_compute_key
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};
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return &ret;
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}
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/*
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* Initialize a GF(2^m)-based EC_GROUP structure. Note that all other members
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* are handled by EC_GROUP_new.
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*/
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int ec_GF2m_simple_group_init(EC_GROUP *group)
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{
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group->field = BN_new();
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group->a = BN_new();
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group->b = BN_new();
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if (group->field == NULL || group->a == NULL || group->b == NULL) {
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BN_free(group->field);
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BN_free(group->a);
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BN_free(group->b);
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return 0;
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}
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return 1;
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}
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/*
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* Free a GF(2^m)-based EC_GROUP structure. Note that all other members are
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* handled by EC_GROUP_free.
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*/
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void ec_GF2m_simple_group_finish(EC_GROUP *group)
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{
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BN_free(group->field);
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BN_free(group->a);
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BN_free(group->b);
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}
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/*
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* Clear and free a GF(2^m)-based EC_GROUP structure. Note that all other
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* members are handled by EC_GROUP_clear_free.
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*/
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void ec_GF2m_simple_group_clear_finish(EC_GROUP *group)
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{
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BN_clear_free(group->field);
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BN_clear_free(group->a);
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BN_clear_free(group->b);
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group->poly[0] = 0;
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group->poly[1] = 0;
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group->poly[2] = 0;
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group->poly[3] = 0;
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group->poly[4] = 0;
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group->poly[5] = -1;
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}
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/*
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* Copy a GF(2^m)-based EC_GROUP structure. Note that all other members are
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* handled by EC_GROUP_copy.
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*/
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int ec_GF2m_simple_group_copy(EC_GROUP *dest, const EC_GROUP *src)
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{
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if (!BN_copy(dest->field, src->field))
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return 0;
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if (!BN_copy(dest->a, src->a))
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return 0;
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if (!BN_copy(dest->b, src->b))
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return 0;
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dest->poly[0] = src->poly[0];
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dest->poly[1] = src->poly[1];
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dest->poly[2] = src->poly[2];
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dest->poly[3] = src->poly[3];
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dest->poly[4] = src->poly[4];
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dest->poly[5] = src->poly[5];
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if (bn_wexpand(dest->a, (int)(dest->poly[0] + BN_BITS2 - 1) / BN_BITS2) ==
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NULL)
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return 0;
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if (bn_wexpand(dest->b, (int)(dest->poly[0] + BN_BITS2 - 1) / BN_BITS2) ==
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NULL)
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return 0;
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bn_set_all_zero(dest->a);
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bn_set_all_zero(dest->b);
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return 1;
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}
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/* Set the curve parameters of an EC_GROUP structure. */
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int ec_GF2m_simple_group_set_curve(EC_GROUP *group,
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const BIGNUM *p, const BIGNUM *a,
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const BIGNUM *b, BN_CTX *ctx)
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{
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int ret = 0, i;
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/* group->field */
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if (!BN_copy(group->field, p))
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goto err;
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i = BN_GF2m_poly2arr(group->field, group->poly, 6) - 1;
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if ((i != 5) && (i != 3)) {
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ECerr(EC_F_EC_GF2M_SIMPLE_GROUP_SET_CURVE, EC_R_UNSUPPORTED_FIELD);
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goto err;
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}
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/* group->a */
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if (!BN_GF2m_mod_arr(group->a, a, group->poly))
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goto err;
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if (bn_wexpand(group->a, (int)(group->poly[0] + BN_BITS2 - 1) / BN_BITS2)
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== NULL)
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goto err;
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bn_set_all_zero(group->a);
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/* group->b */
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if (!BN_GF2m_mod_arr(group->b, b, group->poly))
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goto err;
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if (bn_wexpand(group->b, (int)(group->poly[0] + BN_BITS2 - 1) / BN_BITS2)
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== NULL)
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goto err;
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bn_set_all_zero(group->b);
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ret = 1;
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err:
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return ret;
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}
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/*
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* Get the curve parameters of an EC_GROUP structure. If p, a, or b are NULL
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* then there values will not be set but the method will return with success.
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*/
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int ec_GF2m_simple_group_get_curve(const EC_GROUP *group, BIGNUM *p,
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BIGNUM *a, BIGNUM *b, BN_CTX *ctx)
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{
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int ret = 0;
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if (p != NULL) {
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if (!BN_copy(p, group->field))
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return 0;
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}
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if (a != NULL) {
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if (!BN_copy(a, group->a))
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goto err;
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}
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if (b != NULL) {
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if (!BN_copy(b, group->b))
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goto err;
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}
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ret = 1;
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err:
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return ret;
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}
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/*
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* Gets the degree of the field. For a curve over GF(2^m) this is the value
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* m.
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*/
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int ec_GF2m_simple_group_get_degree(const EC_GROUP *group)
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{
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return BN_num_bits(group->field) - 1;
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}
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/*
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* Checks the discriminant of the curve. y^2 + x*y = x^3 + a*x^2 + b is an
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* elliptic curve <=> b != 0 (mod p)
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*/
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int ec_GF2m_simple_group_check_discriminant(const EC_GROUP *group,
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BN_CTX *ctx)
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{
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int ret = 0;
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BIGNUM *b;
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BN_CTX *new_ctx = NULL;
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if (ctx == NULL) {
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ctx = new_ctx = BN_CTX_new();
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if (ctx == NULL) {
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ECerr(EC_F_EC_GF2M_SIMPLE_GROUP_CHECK_DISCRIMINANT,
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ERR_R_MALLOC_FAILURE);
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goto err;
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}
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}
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BN_CTX_start(ctx);
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b = BN_CTX_get(ctx);
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if (b == NULL)
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goto err;
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if (!BN_GF2m_mod_arr(b, group->b, group->poly))
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goto err;
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/*
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* check the discriminant: y^2 + x*y = x^3 + a*x^2 + b is an elliptic
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* curve <=> b != 0 (mod p)
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*/
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if (BN_is_zero(b))
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goto err;
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ret = 1;
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err:
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if (ctx != NULL)
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BN_CTX_end(ctx);
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BN_CTX_free(new_ctx);
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return ret;
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}
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/* Initializes an EC_POINT. */
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int ec_GF2m_simple_point_init(EC_POINT *point)
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{
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point->X = BN_new();
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point->Y = BN_new();
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point->Z = BN_new();
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if (point->X == NULL || point->Y == NULL || point->Z == NULL) {
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BN_free(point->X);
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BN_free(point->Y);
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BN_free(point->Z);
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return 0;
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}
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return 1;
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}
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/* Frees an EC_POINT. */
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void ec_GF2m_simple_point_finish(EC_POINT *point)
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{
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BN_free(point->X);
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BN_free(point->Y);
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BN_free(point->Z);
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}
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/* Clears and frees an EC_POINT. */
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void ec_GF2m_simple_point_clear_finish(EC_POINT *point)
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{
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BN_clear_free(point->X);
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BN_clear_free(point->Y);
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BN_clear_free(point->Z);
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point->Z_is_one = 0;
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}
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/*
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* Copy the contents of one EC_POINT into another. Assumes dest is
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* initialized.
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*/
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int ec_GF2m_simple_point_copy(EC_POINT *dest, const EC_POINT *src)
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{
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if (!BN_copy(dest->X, src->X))
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return 0;
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if (!BN_copy(dest->Y, src->Y))
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return 0;
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if (!BN_copy(dest->Z, src->Z))
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return 0;
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dest->Z_is_one = src->Z_is_one;
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return 1;
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}
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/*
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* Set an EC_POINT to the point at infinity. A point at infinity is
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* represented by having Z=0.
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*/
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int ec_GF2m_simple_point_set_to_infinity(const EC_GROUP *group,
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EC_POINT *point)
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{
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point->Z_is_one = 0;
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BN_zero(point->Z);
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return 1;
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}
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/*
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* Set the coordinates of an EC_POINT using affine coordinates. Note that
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* the simple implementation only uses affine coordinates.
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*/
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int ec_GF2m_simple_point_set_affine_coordinates(const EC_GROUP *group,
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EC_POINT *point,
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const BIGNUM *x,
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const BIGNUM *y, BN_CTX *ctx)
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{
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int ret = 0;
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if (x == NULL || y == NULL) {
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ECerr(EC_F_EC_GF2M_SIMPLE_POINT_SET_AFFINE_COORDINATES,
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ERR_R_PASSED_NULL_PARAMETER);
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return 0;
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}
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if (!BN_copy(point->X, x))
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goto err;
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BN_set_negative(point->X, 0);
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if (!BN_copy(point->Y, y))
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goto err;
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BN_set_negative(point->Y, 0);
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if (!BN_copy(point->Z, BN_value_one()))
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goto err;
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BN_set_negative(point->Z, 0);
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point->Z_is_one = 1;
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ret = 1;
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|
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err:
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return ret;
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}
|
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/*
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* Gets the affine coordinates of an EC_POINT. Note that the simple
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* implementation only uses affine coordinates.
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*/
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int ec_GF2m_simple_point_get_affine_coordinates(const EC_GROUP *group,
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const EC_POINT *point,
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BIGNUM *x, BIGNUM *y,
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BN_CTX *ctx)
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{
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int ret = 0;
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|
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if (EC_POINT_is_at_infinity(group, point)) {
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ECerr(EC_F_EC_GF2M_SIMPLE_POINT_GET_AFFINE_COORDINATES,
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EC_R_POINT_AT_INFINITY);
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return 0;
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}
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|
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if (BN_cmp(point->Z, BN_value_one())) {
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ECerr(EC_F_EC_GF2M_SIMPLE_POINT_GET_AFFINE_COORDINATES,
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ERR_R_SHOULD_NOT_HAVE_BEEN_CALLED);
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return 0;
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|
}
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if (x != NULL) {
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if (!BN_copy(x, point->X))
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goto err;
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BN_set_negative(x, 0);
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}
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if (y != NULL) {
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if (!BN_copy(y, point->Y))
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goto err;
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BN_set_negative(y, 0);
|
|
}
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ret = 1;
|
|
|
|
err:
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return ret;
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|
}
|
|
|
|
/*
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* Computes a + b and stores the result in r. r could be a or b, a could be
|
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* b. Uses algorithm A.10.2 of IEEE P1363.
|
|
*/
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int ec_GF2m_simple_add(const EC_GROUP *group, EC_POINT *r, const EC_POINT *a,
|
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const EC_POINT *b, BN_CTX *ctx)
|
|
{
|
|
BN_CTX *new_ctx = NULL;
|
|
BIGNUM *x0, *y0, *x1, *y1, *x2, *y2, *s, *t;
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int ret = 0;
|
|
|
|
if (EC_POINT_is_at_infinity(group, a)) {
|
|
if (!EC_POINT_copy(r, b))
|
|
return 0;
|
|
return 1;
|
|
}
|
|
|
|
if (EC_POINT_is_at_infinity(group, b)) {
|
|
if (!EC_POINT_copy(r, a))
|
|
return 0;
|
|
return 1;
|
|
}
|
|
|
|
if (ctx == NULL) {
|
|
ctx = new_ctx = BN_CTX_new();
|
|
if (ctx == NULL)
|
|
return 0;
|
|
}
|
|
|
|
BN_CTX_start(ctx);
|
|
x0 = BN_CTX_get(ctx);
|
|
y0 = BN_CTX_get(ctx);
|
|
x1 = BN_CTX_get(ctx);
|
|
y1 = BN_CTX_get(ctx);
|
|
x2 = BN_CTX_get(ctx);
|
|
y2 = BN_CTX_get(ctx);
|
|
s = BN_CTX_get(ctx);
|
|
t = BN_CTX_get(ctx);
|
|
if (t == NULL)
|
|
goto err;
|
|
|
|
if (a->Z_is_one) {
|
|
if (!BN_copy(x0, a->X))
|
|
goto err;
|
|
if (!BN_copy(y0, a->Y))
|
|
goto err;
|
|
} else {
|
|
if (!EC_POINT_get_affine_coordinates_GF2m(group, a, x0, y0, ctx))
|
|
goto err;
|
|
}
|
|
if (b->Z_is_one) {
|
|
if (!BN_copy(x1, b->X))
|
|
goto err;
|
|
if (!BN_copy(y1, b->Y))
|
|
goto err;
|
|
} else {
|
|
if (!EC_POINT_get_affine_coordinates_GF2m(group, b, x1, y1, ctx))
|
|
goto err;
|
|
}
|
|
|
|
if (BN_GF2m_cmp(x0, x1)) {
|
|
if (!BN_GF2m_add(t, x0, x1))
|
|
goto err;
|
|
if (!BN_GF2m_add(s, y0, y1))
|
|
goto err;
|
|
if (!group->meth->field_div(group, s, s, t, ctx))
|
|
goto err;
|
|
if (!group->meth->field_sqr(group, x2, s, ctx))
|
|
goto err;
|
|
if (!BN_GF2m_add(x2, x2, group->a))
|
|
goto err;
|
|
if (!BN_GF2m_add(x2, x2, s))
|
|
goto err;
|
|
if (!BN_GF2m_add(x2, x2, t))
|
|
goto err;
|
|
} else {
|
|
if (BN_GF2m_cmp(y0, y1) || BN_is_zero(x1)) {
|
|
if (!EC_POINT_set_to_infinity(group, r))
|
|
goto err;
|
|
ret = 1;
|
|
goto err;
|
|
}
|
|
if (!group->meth->field_div(group, s, y1, x1, ctx))
|
|
goto err;
|
|
if (!BN_GF2m_add(s, s, x1))
|
|
goto err;
|
|
|
|
if (!group->meth->field_sqr(group, x2, s, ctx))
|
|
goto err;
|
|
if (!BN_GF2m_add(x2, x2, s))
|
|
goto err;
|
|
if (!BN_GF2m_add(x2, x2, group->a))
|
|
goto err;
|
|
}
|
|
|
|
if (!BN_GF2m_add(y2, x1, x2))
|
|
goto err;
|
|
if (!group->meth->field_mul(group, y2, y2, s, ctx))
|
|
goto err;
|
|
if (!BN_GF2m_add(y2, y2, x2))
|
|
goto err;
|
|
if (!BN_GF2m_add(y2, y2, y1))
|
|
goto err;
|
|
|
|
if (!EC_POINT_set_affine_coordinates_GF2m(group, r, x2, y2, ctx))
|
|
goto err;
|
|
|
|
ret = 1;
|
|
|
|
err:
|
|
BN_CTX_end(ctx);
|
|
BN_CTX_free(new_ctx);
|
|
return ret;
|
|
}
|
|
|
|
/*
|
|
* Computes 2 * a and stores the result in r. r could be a. Uses algorithm
|
|
* A.10.2 of IEEE P1363.
|
|
*/
|
|
int ec_GF2m_simple_dbl(const EC_GROUP *group, EC_POINT *r, const EC_POINT *a,
|
|
BN_CTX *ctx)
|
|
{
|
|
return ec_GF2m_simple_add(group, r, a, a, ctx);
|
|
}
|
|
|
|
int ec_GF2m_simple_invert(const EC_GROUP *group, EC_POINT *point, BN_CTX *ctx)
|
|
{
|
|
if (EC_POINT_is_at_infinity(group, point) || BN_is_zero(point->Y))
|
|
/* point is its own inverse */
|
|
return 1;
|
|
|
|
if (!EC_POINT_make_affine(group, point, ctx))
|
|
return 0;
|
|
return BN_GF2m_add(point->Y, point->X, point->Y);
|
|
}
|
|
|
|
/* Indicates whether the given point is the point at infinity. */
|
|
int ec_GF2m_simple_is_at_infinity(const EC_GROUP *group,
|
|
const EC_POINT *point)
|
|
{
|
|
return BN_is_zero(point->Z);
|
|
}
|
|
|
|
/*-
|
|
* Determines whether the given EC_POINT is an actual point on the curve defined
|
|
* in the EC_GROUP. A point is valid if it satisfies the Weierstrass equation:
|
|
* y^2 + x*y = x^3 + a*x^2 + b.
|
|
*/
|
|
int ec_GF2m_simple_is_on_curve(const EC_GROUP *group, const EC_POINT *point,
|
|
BN_CTX *ctx)
|
|
{
|
|
int ret = -1;
|
|
BN_CTX *new_ctx = NULL;
|
|
BIGNUM *lh, *y2;
|
|
int (*field_mul) (const EC_GROUP *, BIGNUM *, const BIGNUM *,
|
|
const BIGNUM *, BN_CTX *);
|
|
int (*field_sqr) (const EC_GROUP *, BIGNUM *, const BIGNUM *, BN_CTX *);
|
|
|
|
if (EC_POINT_is_at_infinity(group, point))
|
|
return 1;
|
|
|
|
field_mul = group->meth->field_mul;
|
|
field_sqr = group->meth->field_sqr;
|
|
|
|
/* only support affine coordinates */
|
|
if (!point->Z_is_one)
|
|
return -1;
|
|
|
|
if (ctx == NULL) {
|
|
ctx = new_ctx = BN_CTX_new();
|
|
if (ctx == NULL)
|
|
return -1;
|
|
}
|
|
|
|
BN_CTX_start(ctx);
|
|
y2 = BN_CTX_get(ctx);
|
|
lh = BN_CTX_get(ctx);
|
|
if (lh == NULL)
|
|
goto err;
|
|
|
|
/*-
|
|
* We have a curve defined by a Weierstrass equation
|
|
* y^2 + x*y = x^3 + a*x^2 + b.
|
|
* <=> x^3 + a*x^2 + x*y + b + y^2 = 0
|
|
* <=> ((x + a) * x + y ) * x + b + y^2 = 0
|
|
*/
|
|
if (!BN_GF2m_add(lh, point->X, group->a))
|
|
goto err;
|
|
if (!field_mul(group, lh, lh, point->X, ctx))
|
|
goto err;
|
|
if (!BN_GF2m_add(lh, lh, point->Y))
|
|
goto err;
|
|
if (!field_mul(group, lh, lh, point->X, ctx))
|
|
goto err;
|
|
if (!BN_GF2m_add(lh, lh, group->b))
|
|
goto err;
|
|
if (!field_sqr(group, y2, point->Y, ctx))
|
|
goto err;
|
|
if (!BN_GF2m_add(lh, lh, y2))
|
|
goto err;
|
|
ret = BN_is_zero(lh);
|
|
|
|
err:
|
|
BN_CTX_end(ctx);
|
|
BN_CTX_free(new_ctx);
|
|
return ret;
|
|
}
|
|
|
|
/*-
|
|
* Indicates whether two points are equal.
|
|
* Return values:
|
|
* -1 error
|
|
* 0 equal (in affine coordinates)
|
|
* 1 not equal
|
|
*/
|
|
int ec_GF2m_simple_cmp(const EC_GROUP *group, const EC_POINT *a,
|
|
const EC_POINT *b, BN_CTX *ctx)
|
|
{
|
|
BIGNUM *aX, *aY, *bX, *bY;
|
|
BN_CTX *new_ctx = NULL;
|
|
int ret = -1;
|
|
|
|
if (EC_POINT_is_at_infinity(group, a)) {
|
|
return EC_POINT_is_at_infinity(group, b) ? 0 : 1;
|
|
}
|
|
|
|
if (EC_POINT_is_at_infinity(group, b))
|
|
return 1;
|
|
|
|
if (a->Z_is_one && b->Z_is_one) {
|
|
return ((BN_cmp(a->X, b->X) == 0) && BN_cmp(a->Y, b->Y) == 0) ? 0 : 1;
|
|
}
|
|
|
|
if (ctx == NULL) {
|
|
ctx = new_ctx = BN_CTX_new();
|
|
if (ctx == NULL)
|
|
return -1;
|
|
}
|
|
|
|
BN_CTX_start(ctx);
|
|
aX = BN_CTX_get(ctx);
|
|
aY = BN_CTX_get(ctx);
|
|
bX = BN_CTX_get(ctx);
|
|
bY = BN_CTX_get(ctx);
|
|
if (bY == NULL)
|
|
goto err;
|
|
|
|
if (!EC_POINT_get_affine_coordinates_GF2m(group, a, aX, aY, ctx))
|
|
goto err;
|
|
if (!EC_POINT_get_affine_coordinates_GF2m(group, b, bX, bY, ctx))
|
|
goto err;
|
|
ret = ((BN_cmp(aX, bX) == 0) && BN_cmp(aY, bY) == 0) ? 0 : 1;
|
|
|
|
err:
|
|
BN_CTX_end(ctx);
|
|
BN_CTX_free(new_ctx);
|
|
return ret;
|
|
}
|
|
|
|
/* Forces the given EC_POINT to internally use affine coordinates. */
|
|
int ec_GF2m_simple_make_affine(const EC_GROUP *group, EC_POINT *point,
|
|
BN_CTX *ctx)
|
|
{
|
|
BN_CTX *new_ctx = NULL;
|
|
BIGNUM *x, *y;
|
|
int ret = 0;
|
|
|
|
if (point->Z_is_one || EC_POINT_is_at_infinity(group, point))
|
|
return 1;
|
|
|
|
if (ctx == NULL) {
|
|
ctx = new_ctx = BN_CTX_new();
|
|
if (ctx == NULL)
|
|
return 0;
|
|
}
|
|
|
|
BN_CTX_start(ctx);
|
|
x = BN_CTX_get(ctx);
|
|
y = BN_CTX_get(ctx);
|
|
if (y == NULL)
|
|
goto err;
|
|
|
|
if (!EC_POINT_get_affine_coordinates_GF2m(group, point, x, y, ctx))
|
|
goto err;
|
|
if (!BN_copy(point->X, x))
|
|
goto err;
|
|
if (!BN_copy(point->Y, y))
|
|
goto err;
|
|
if (!BN_one(point->Z))
|
|
goto err;
|
|
point->Z_is_one = 1;
|
|
|
|
ret = 1;
|
|
|
|
err:
|
|
BN_CTX_end(ctx);
|
|
BN_CTX_free(new_ctx);
|
|
return ret;
|
|
}
|
|
|
|
/*
|
|
* Forces each of the EC_POINTs in the given array to use affine coordinates.
|
|
*/
|
|
int ec_GF2m_simple_points_make_affine(const EC_GROUP *group, size_t num,
|
|
EC_POINT *points[], BN_CTX *ctx)
|
|
{
|
|
size_t i;
|
|
|
|
for (i = 0; i < num; i++) {
|
|
if (!group->meth->make_affine(group, points[i], ctx))
|
|
return 0;
|
|
}
|
|
|
|
return 1;
|
|
}
|
|
|
|
/* Wrapper to simple binary polynomial field multiplication implementation. */
|
|
int ec_GF2m_simple_field_mul(const EC_GROUP *group, BIGNUM *r,
|
|
const BIGNUM *a, const BIGNUM *b, BN_CTX *ctx)
|
|
{
|
|
return BN_GF2m_mod_mul_arr(r, a, b, group->poly, ctx);
|
|
}
|
|
|
|
/* Wrapper to simple binary polynomial field squaring implementation. */
|
|
int ec_GF2m_simple_field_sqr(const EC_GROUP *group, BIGNUM *r,
|
|
const BIGNUM *a, BN_CTX *ctx)
|
|
{
|
|
return BN_GF2m_mod_sqr_arr(r, a, group->poly, ctx);
|
|
}
|
|
|
|
/* Wrapper to simple binary polynomial field division implementation. */
|
|
int ec_GF2m_simple_field_div(const EC_GROUP *group, BIGNUM *r,
|
|
const BIGNUM *a, const BIGNUM *b, BN_CTX *ctx)
|
|
{
|
|
return BN_GF2m_mod_div(r, a, b, group->field, ctx);
|
|
}
|
|
|
|
#endif
|