| /* Originally written by Bodo Moeller for the OpenSSL project. |
| * ==================================================================== |
| * Copyright (c) 1998-2005 The OpenSSL Project. All rights reserved. |
| * |
| * Redistribution and use in source and binary forms, with or without |
| * modification, are permitted provided that the following conditions |
| * are met: |
| * |
| * 1. Redistributions of source code must retain the above copyright |
| * notice, this list of conditions and the following disclaimer. |
| * |
| * 2. Redistributions in binary form must reproduce the above copyright |
| * notice, this list of conditions and the following disclaimer in |
| * the documentation and/or other materials provided with the |
| * distribution. |
| * |
| * 3. All advertising materials mentioning features or use of this |
| * software must display the following acknowledgment: |
| * "This product includes software developed by the OpenSSL Project |
| * for use in the OpenSSL Toolkit. (http://www.openssl.org/)" |
| * |
| * 4. The names "OpenSSL Toolkit" and "OpenSSL Project" must not be used to |
| * endorse or promote products derived from this software without |
| * prior written permission. For written permission, please contact |
| * openssl-core@openssl.org. |
| * |
| * 5. Products derived from this software may not be called "OpenSSL" |
| * nor may "OpenSSL" appear in their names without prior written |
| * permission of the OpenSSL Project. |
| * |
| * 6. Redistributions of any form whatsoever must retain the following |
| * acknowledgment: |
| * "This product includes software developed by the OpenSSL Project |
| * for use in the OpenSSL Toolkit (http://www.openssl.org/)" |
| * |
| * THIS SOFTWARE IS PROVIDED BY THE OpenSSL PROJECT ``AS IS'' AND ANY |
| * EXPRESSED OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE |
| * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR |
| * PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE OpenSSL PROJECT OR |
| * ITS CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, |
| * SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT |
| * NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; |
| * LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) |
| * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, |
| * STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) |
| * ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED |
| * OF THE POSSIBILITY OF SUCH DAMAGE. |
| * ==================================================================== |
| * |
| * This product includes cryptographic software written by Eric Young |
| * (eay@cryptsoft.com). This product includes software written by Tim |
| * Hudson (tjh@cryptsoft.com). |
| * |
| */ |
| /* ==================================================================== |
| * Copyright 2002 Sun Microsystems, Inc. ALL RIGHTS RESERVED. |
| * |
| * Portions of the attached software ("Contribution") are developed by |
| * SUN MICROSYSTEMS, INC., and are contributed to the OpenSSL project. |
| * |
| * The Contribution is licensed pursuant to the OpenSSL open source |
| * license provided above. |
| * |
| * The elliptic curve binary polynomial software is originally written by |
| * Sheueling Chang Shantz and Douglas Stebila of Sun Microsystems |
| * Laboratories. */ |
| |
| #include <openssl/ec.h> |
| |
| #include <openssl/bn.h> |
| #include <openssl/err.h> |
| #include <openssl/mem.h> |
| |
| #include "internal.h" |
| |
| |
| const EC_METHOD *EC_GFp_simple_method(void) { |
| static const EC_METHOD ret = {EC_FLAGS_DEFAULT_OCT, |
| ec_GFp_simple_group_init, |
| ec_GFp_simple_group_finish, |
| ec_GFp_simple_group_clear_finish, |
| ec_GFp_simple_group_copy, |
| ec_GFp_simple_group_set_curve, |
| ec_GFp_simple_group_get_curve, |
| ec_GFp_simple_group_get_degree, |
| ec_GFp_simple_group_check_discriminant, |
| ec_GFp_simple_point_init, |
| ec_GFp_simple_point_finish, |
| ec_GFp_simple_point_clear_finish, |
| ec_GFp_simple_point_copy, |
| ec_GFp_simple_point_set_to_infinity, |
| ec_GFp_simple_set_Jprojective_coordinates_GFp, |
| ec_GFp_simple_get_Jprojective_coordinates_GFp, |
| ec_GFp_simple_point_set_affine_coordinates, |
| ec_GFp_simple_point_get_affine_coordinates, |
| 0, |
| 0, |
| 0, |
| ec_GFp_simple_add, |
| ec_GFp_simple_dbl, |
| ec_GFp_simple_invert, |
| ec_GFp_simple_is_at_infinity, |
| ec_GFp_simple_is_on_curve, |
| ec_GFp_simple_cmp, |
| ec_GFp_simple_make_affine, |
| ec_GFp_simple_points_make_affine, |
| 0 /* mul */, |
| 0 /* precompute_mult */, |
| 0 /* have_precompute_mult */, |
| ec_GFp_simple_field_mul, |
| ec_GFp_simple_field_sqr, |
| 0 /* field_div */, |
| 0 /* field_encode */, |
| 0 /* field_decode */, |
| 0 /* field_set_to_one */}; |
| |
| return &ret; |
| } |
| |
| |
| /* Most method functions in this file are designed to work with non-trivial |
| * representations of field elements if necessary (see ecp_mont.c): while |
| * standard modular addition and subtraction are used, the field_mul and |
| * field_sqr methods will be used for multiplication, and field_encode and |
| * field_decode (if defined) will be used for converting between |
| * representations. |
| |
| * Functions ec_GFp_simple_points_make_affine() and |
| * ec_GFp_simple_point_get_affine_coordinates() specifically assume that if a |
| * non-trivial representation is used, it is a Montgomery representation (i.e. |
| * 'encoding' means multiplying by some factor R). */ |
| |
| int ec_GFp_simple_group_init(EC_GROUP *group) { |
| BN_init(&group->field); |
| BN_init(&group->a); |
| BN_init(&group->b); |
| group->a_is_minus3 = 0; |
| return 1; |
| } |
| |
| void ec_GFp_simple_group_finish(EC_GROUP *group) { |
| BN_free(&group->field); |
| BN_free(&group->a); |
| BN_free(&group->b); |
| } |
| |
| void ec_GFp_simple_group_clear_finish(EC_GROUP *group) { |
| BN_clear_free(&group->field); |
| BN_clear_free(&group->a); |
| BN_clear_free(&group->b); |
| } |
| |
| int ec_GFp_simple_group_copy(EC_GROUP *dest, const EC_GROUP *src) { |
| if (!BN_copy(&dest->field, &src->field) || |
| !BN_copy(&dest->a, &src->a) || |
| !BN_copy(&dest->b, &src->b)) { |
| return 0; |
| } |
| |
| dest->a_is_minus3 = src->a_is_minus3; |
| return 1; |
| } |
| |
| int ec_GFp_simple_group_set_curve(EC_GROUP *group, const BIGNUM *p, |
| const BIGNUM *a, const BIGNUM *b, |
| BN_CTX *ctx) { |
| int ret = 0; |
| BN_CTX *new_ctx = NULL; |
| BIGNUM *tmp_a; |
| |
| /* p must be a prime > 3 */ |
| if (BN_num_bits(p) <= 2 || !BN_is_odd(p)) { |
| OPENSSL_PUT_ERROR(EC, ec_GFp_simple_group_set_curve, EC_R_INVALID_FIELD); |
| return 0; |
| } |
| |
| if (ctx == NULL) { |
| ctx = new_ctx = BN_CTX_new(); |
| if (ctx == NULL) |
| return 0; |
| } |
| |
| BN_CTX_start(ctx); |
| tmp_a = BN_CTX_get(ctx); |
| if (tmp_a == NULL) |
| goto err; |
| |
| /* group->field */ |
| if (!BN_copy(&group->field, p)) |
| goto err; |
| BN_set_negative(&group->field, 0); |
| |
| /* group->a */ |
| if (!BN_nnmod(tmp_a, a, p, ctx)) |
| goto err; |
| if (group->meth->field_encode) { |
| if (!group->meth->field_encode(group, &group->a, tmp_a, ctx)) |
| goto err; |
| } else if (!BN_copy(&group->a, tmp_a)) |
| goto err; |
| |
| /* group->b */ |
| if (!BN_nnmod(&group->b, b, p, ctx)) |
| goto err; |
| if (group->meth->field_encode) |
| if (!group->meth->field_encode(group, &group->b, &group->b, ctx)) |
| goto err; |
| |
| /* group->a_is_minus3 */ |
| if (!BN_add_word(tmp_a, 3)) |
| goto err; |
| group->a_is_minus3 = (0 == BN_cmp(tmp_a, &group->field)); |
| |
| ret = 1; |
| |
| err: |
| BN_CTX_end(ctx); |
| if (new_ctx != NULL) |
| BN_CTX_free(new_ctx); |
| return ret; |
| } |
| |
| int ec_GFp_simple_group_get_curve(const EC_GROUP *group, BIGNUM *p, BIGNUM *a, |
| BIGNUM *b, BN_CTX *ctx) { |
| int ret = 0; |
| BN_CTX *new_ctx = NULL; |
| |
| if (p != NULL) { |
| if (!BN_copy(p, &group->field)) |
| return 0; |
| } |
| |
| if (a != NULL || b != NULL) { |
| if (group->meth->field_decode) { |
| if (ctx == NULL) { |
| ctx = new_ctx = BN_CTX_new(); |
| if (ctx == NULL) |
| return 0; |
| } |
| if (a != NULL) { |
| if (!group->meth->field_decode(group, a, &group->a, ctx)) |
| goto err; |
| } |
| if (b != NULL) { |
| if (!group->meth->field_decode(group, b, &group->b, ctx)) |
| goto err; |
| } |
| } else { |
| if (a != NULL) { |
| if (!BN_copy(a, &group->a)) |
| goto err; |
| } |
| if (b != NULL) { |
| if (!BN_copy(b, &group->b)) |
| goto err; |
| } |
| } |
| } |
| |
| ret = 1; |
| |
| err: |
| if (new_ctx) |
| BN_CTX_free(new_ctx); |
| return ret; |
| } |
| |
| int ec_GFp_simple_group_get_degree(const EC_GROUP *group) { |
| return BN_num_bits(&group->field); |
| } |
| |
| int ec_GFp_simple_group_check_discriminant(const EC_GROUP *group, BN_CTX *ctx) { |
| int ret = 0; |
| BIGNUM *a, *b, *order, *tmp_1, *tmp_2; |
| const BIGNUM *p = &group->field; |
| BN_CTX *new_ctx = NULL; |
| |
| if (ctx == NULL) { |
| ctx = new_ctx = BN_CTX_new(); |
| if (ctx == NULL) { |
| OPENSSL_PUT_ERROR(EC, ec_GFp_simple_group_check_discriminant, |
| ERR_R_MALLOC_FAILURE); |
| goto err; |
| } |
| } |
| BN_CTX_start(ctx); |
| a = BN_CTX_get(ctx); |
| b = BN_CTX_get(ctx); |
| tmp_1 = BN_CTX_get(ctx); |
| tmp_2 = BN_CTX_get(ctx); |
| order = BN_CTX_get(ctx); |
| if (order == NULL) |
| goto err; |
| |
| if (group->meth->field_decode) { |
| if (!group->meth->field_decode(group, a, &group->a, ctx)) |
| goto err; |
| if (!group->meth->field_decode(group, b, &group->b, ctx)) |
| goto err; |
| } else { |
| if (!BN_copy(a, &group->a)) |
| goto err; |
| if (!BN_copy(b, &group->b)) |
| goto err; |
| } |
| |
| /* check the discriminant: |
| * y^2 = x^3 + a*x + b is an elliptic curve <=> 4*a^3 + 27*b^2 != 0 (mod p) |
| * 0 =< a, b < p */ |
| if (BN_is_zero(a)) { |
| if (BN_is_zero(b)) |
| goto err; |
| } else if (!BN_is_zero(b)) { |
| if (!BN_mod_sqr(tmp_1, a, p, ctx)) |
| goto err; |
| if (!BN_mod_mul(tmp_2, tmp_1, a, p, ctx)) |
| goto err; |
| if (!BN_lshift(tmp_1, tmp_2, 2)) |
| goto err; |
| /* tmp_1 = 4*a^3 */ |
| |
| if (!BN_mod_sqr(tmp_2, b, p, ctx)) |
| goto err; |
| if (!BN_mul_word(tmp_2, 27)) |
| goto err; |
| /* tmp_2 = 27*b^2 */ |
| |
| if (!BN_mod_add(a, tmp_1, tmp_2, p, ctx)) |
| goto err; |
| if (BN_is_zero(a)) |
| goto err; |
| } |
| ret = 1; |
| |
| err: |
| if (ctx != NULL) |
| BN_CTX_end(ctx); |
| if (new_ctx != NULL) |
| BN_CTX_free(new_ctx); |
| return ret; |
| } |
| |
| int ec_GFp_simple_point_init(EC_POINT *point) { |
| BN_init(&point->X); |
| BN_init(&point->Y); |
| BN_init(&point->Z); |
| point->Z_is_one = 0; |
| |
| return 1; |
| } |
| |
| void ec_GFp_simple_point_finish(EC_POINT *point) { |
| BN_free(&point->X); |
| BN_free(&point->Y); |
| BN_free(&point->Z); |
| } |
| |
| void ec_GFp_simple_point_clear_finish(EC_POINT *point) { |
| BN_clear_free(&point->X); |
| BN_clear_free(&point->Y); |
| BN_clear_free(&point->Z); |
| point->Z_is_one = 0; |
| } |
| |
| int ec_GFp_simple_point_copy(EC_POINT *dest, const EC_POINT *src) { |
| if (!BN_copy(&dest->X, &src->X)) |
| return 0; |
| if (!BN_copy(&dest->Y, &src->Y)) |
| return 0; |
| if (!BN_copy(&dest->Z, &src->Z)) |
| return 0; |
| dest->Z_is_one = src->Z_is_one; |
| |
| return 1; |
| } |
| |
| int ec_GFp_simple_point_set_to_infinity(const EC_GROUP *group, |
| EC_POINT *point) { |
| point->Z_is_one = 0; |
| BN_zero(&point->Z); |
| return 1; |
| } |
| |
| int ec_GFp_simple_set_Jprojective_coordinates_GFp( |
| const EC_GROUP *group, EC_POINT *point, const BIGNUM *x, const BIGNUM *y, |
| const BIGNUM *z, BN_CTX *ctx) { |
| BN_CTX *new_ctx = NULL; |
| int ret = 0; |
| |
| if (ctx == NULL) { |
| ctx = new_ctx = BN_CTX_new(); |
| if (ctx == NULL) |
| return 0; |
| } |
| |
| if (x != NULL) { |
| if (!BN_nnmod(&point->X, x, &group->field, ctx)) |
| goto err; |
| if (group->meth->field_encode) { |
| if (!group->meth->field_encode(group, &point->X, &point->X, ctx)) |
| goto err; |
| } |
| } |
| |
| if (y != NULL) { |
| if (!BN_nnmod(&point->Y, y, &group->field, ctx)) |
| goto err; |
| if (group->meth->field_encode) { |
| if (!group->meth->field_encode(group, &point->Y, &point->Y, ctx)) |
| goto err; |
| } |
| } |
| |
| if (z != NULL) { |
| int Z_is_one; |
| |
| if (!BN_nnmod(&point->Z, z, &group->field, ctx)) |
| goto err; |
| Z_is_one = BN_is_one(&point->Z); |
| if (group->meth->field_encode) { |
| if (Z_is_one && (group->meth->field_set_to_one != 0)) { |
| if (!group->meth->field_set_to_one(group, &point->Z, ctx)) |
| goto err; |
| } else { |
| if (!group->meth->field_encode(group, &point->Z, &point->Z, ctx)) |
| goto err; |
| } |
| } |
| point->Z_is_one = Z_is_one; |
| } |
| |
| ret = 1; |
| |
| err: |
| if (new_ctx != NULL) |
| BN_CTX_free(new_ctx); |
| return ret; |
| } |
| |
| int ec_GFp_simple_get_Jprojective_coordinates_GFp(const EC_GROUP *group, |
| const EC_POINT *point, |
| BIGNUM *x, BIGNUM *y, |
| BIGNUM *z, BN_CTX *ctx) { |
| BN_CTX *new_ctx = NULL; |
| int ret = 0; |
| |
| if (group->meth->field_decode != 0) { |
| if (ctx == NULL) { |
| ctx = new_ctx = BN_CTX_new(); |
| if (ctx == NULL) |
| return 0; |
| } |
| |
| if (x != NULL) { |
| if (!group->meth->field_decode(group, x, &point->X, ctx)) |
| goto err; |
| } |
| if (y != NULL) { |
| if (!group->meth->field_decode(group, y, &point->Y, ctx)) |
| goto err; |
| } |
| if (z != NULL) { |
| if (!group->meth->field_decode(group, z, &point->Z, ctx)) |
| goto err; |
| } |
| } else { |
| if (x != NULL) { |
| if (!BN_copy(x, &point->X)) |
| goto err; |
| } |
| if (y != NULL) { |
| if (!BN_copy(y, &point->Y)) |
| goto err; |
| } |
| if (z != NULL) { |
| if (!BN_copy(z, &point->Z)) |
| goto err; |
| } |
| } |
| |
| ret = 1; |
| |
| err: |
| if (new_ctx != NULL) |
| BN_CTX_free(new_ctx); |
| return ret; |
| } |
| |
| int ec_GFp_simple_point_set_affine_coordinates(const EC_GROUP *group, |
| EC_POINT *point, const BIGNUM *x, |
| const BIGNUM *y, BN_CTX *ctx) { |
| if (x == NULL || y == NULL) { |
| /* unlike for projective coordinates, we do not tolerate this */ |
| OPENSSL_PUT_ERROR(EC, ec_GFp_simple_point_set_affine_coordinates, |
| ERR_R_PASSED_NULL_PARAMETER); |
| return 0; |
| } |
| |
| return ec_point_set_Jprojective_coordinates_GFp(group, point, x, y, |
| BN_value_one(), ctx); |
| } |
| |
| int ec_GFp_simple_point_get_affine_coordinates(const EC_GROUP *group, |
| const EC_POINT *point, BIGNUM *x, |
| BIGNUM *y, BN_CTX *ctx) { |
| BN_CTX *new_ctx = NULL; |
| BIGNUM *Z, *Z_1, *Z_2, *Z_3; |
| const BIGNUM *Z_; |
| int ret = 0; |
| |
| if (EC_POINT_is_at_infinity(group, point)) { |
| OPENSSL_PUT_ERROR(EC, ec_GFp_simple_point_get_affine_coordinates, |
| EC_R_POINT_AT_INFINITY); |
| return 0; |
| } |
| |
| if (ctx == NULL) { |
| ctx = new_ctx = BN_CTX_new(); |
| if (ctx == NULL) |
| return 0; |
| } |
| |
| BN_CTX_start(ctx); |
| Z = BN_CTX_get(ctx); |
| Z_1 = BN_CTX_get(ctx); |
| Z_2 = BN_CTX_get(ctx); |
| Z_3 = BN_CTX_get(ctx); |
| if (Z_3 == NULL) |
| goto err; |
| |
| /* transform (X, Y, Z) into (x, y) := (X/Z^2, Y/Z^3) */ |
| |
| if (group->meth->field_decode) { |
| if (!group->meth->field_decode(group, Z, &point->Z, ctx)) |
| goto err; |
| Z_ = Z; |
| } else { |
| Z_ = &point->Z; |
| } |
| |
| if (BN_is_one(Z_)) { |
| if (group->meth->field_decode) { |
| if (x != NULL) { |
| if (!group->meth->field_decode(group, x, &point->X, ctx)) |
| goto err; |
| } |
| if (y != NULL) { |
| if (!group->meth->field_decode(group, y, &point->Y, ctx)) |
| goto err; |
| } |
| } else { |
| if (x != NULL) { |
| if (!BN_copy(x, &point->X)) |
| goto err; |
| } |
| if (y != NULL) { |
| if (!BN_copy(y, &point->Y)) |
| goto err; |
| } |
| } |
| } else { |
| if (!BN_mod_inverse(Z_1, Z_, &group->field, ctx)) { |
| OPENSSL_PUT_ERROR(EC, ec_GFp_simple_point_get_affine_coordinates, |
| ERR_R_BN_LIB); |
| goto err; |
| } |
| |
| if (group->meth->field_encode == 0) { |
| /* field_sqr works on standard representation */ |
| if (!group->meth->field_sqr(group, Z_2, Z_1, ctx)) |
| goto err; |
| } else { |
| if (!BN_mod_sqr(Z_2, Z_1, &group->field, ctx)) |
| goto err; |
| } |
| |
| if (x != NULL) { |
| /* in the Montgomery case, field_mul will cancel out Montgomery factor in |
| * X: */ |
| if (!group->meth->field_mul(group, x, &point->X, Z_2, ctx)) |
| goto err; |
| } |
| |
| if (y != NULL) { |
| if (group->meth->field_encode == 0) { |
| /* field_mul works on standard representation */ |
| if (!group->meth->field_mul(group, Z_3, Z_2, Z_1, ctx)) |
| goto err; |
| } else { |
| if (!BN_mod_mul(Z_3, Z_2, Z_1, &group->field, ctx)) |
| goto err; |
| } |
| |
| /* in the Montgomery case, field_mul will cancel out Montgomery factor in |
| * Y: */ |
| if (!group->meth->field_mul(group, y, &point->Y, Z_3, ctx)) |
| goto err; |
| } |
| } |
| |
| ret = 1; |
| |
| err: |
| BN_CTX_end(ctx); |
| if (new_ctx != NULL) |
| BN_CTX_free(new_ctx); |
| return ret; |
| } |
| |
| int ec_GFp_simple_add(const EC_GROUP *group, EC_POINT *r, const EC_POINT *a, |
| const EC_POINT *b, BN_CTX *ctx) { |
| int (*field_mul)(const EC_GROUP *, BIGNUM *, const BIGNUM *, const BIGNUM *, |
| BN_CTX *); |
| int (*field_sqr)(const EC_GROUP *, BIGNUM *, const BIGNUM *, BN_CTX *); |
| const BIGNUM *p; |
| BN_CTX *new_ctx = NULL; |
| BIGNUM *n0, *n1, *n2, *n3, *n4, *n5, *n6; |
| int ret = 0; |
| |
| if (a == b) |
| return EC_POINT_dbl(group, r, a, ctx); |
| if (EC_POINT_is_at_infinity(group, a)) |
| return EC_POINT_copy(r, b); |
| if (EC_POINT_is_at_infinity(group, b)) |
| return EC_POINT_copy(r, a); |
| |
| field_mul = group->meth->field_mul; |
| field_sqr = group->meth->field_sqr; |
| p = &group->field; |
| |
| if (ctx == NULL) { |
| ctx = new_ctx = BN_CTX_new(); |
| if (ctx == NULL) |
| return 0; |
| } |
| |
| BN_CTX_start(ctx); |
| n0 = BN_CTX_get(ctx); |
| n1 = BN_CTX_get(ctx); |
| n2 = BN_CTX_get(ctx); |
| n3 = BN_CTX_get(ctx); |
| n4 = BN_CTX_get(ctx); |
| n5 = BN_CTX_get(ctx); |
| n6 = BN_CTX_get(ctx); |
| if (n6 == NULL) |
| goto end; |
| |
| /* Note that in this function we must not read components of 'a' or 'b' |
| * once we have written the corresponding components of 'r'. |
| * ('r' might be one of 'a' or 'b'.) |
| */ |
| |
| /* n1, n2 */ |
| if (b->Z_is_one) { |
| if (!BN_copy(n1, &a->X)) |
| goto end; |
| if (!BN_copy(n2, &a->Y)) |
| goto end; |
| /* n1 = X_a */ |
| /* n2 = Y_a */ |
| } else { |
| if (!field_sqr(group, n0, &b->Z, ctx)) |
| goto end; |
| if (!field_mul(group, n1, &a->X, n0, ctx)) |
| goto end; |
| /* n1 = X_a * Z_b^2 */ |
| |
| if (!field_mul(group, n0, n0, &b->Z, ctx)) |
| goto end; |
| if (!field_mul(group, n2, &a->Y, n0, ctx)) |
| goto end; |
| /* n2 = Y_a * Z_b^3 */ |
| } |
| |
| /* n3, n4 */ |
| if (a->Z_is_one) { |
| if (!BN_copy(n3, &b->X)) |
| goto end; |
| if (!BN_copy(n4, &b->Y)) |
| goto end; |
| /* n3 = X_b */ |
| /* n4 = Y_b */ |
| } else { |
| if (!field_sqr(group, n0, &a->Z, ctx)) |
| goto end; |
| if (!field_mul(group, n3, &b->X, n0, ctx)) |
| goto end; |
| /* n3 = X_b * Z_a^2 */ |
| |
| if (!field_mul(group, n0, n0, &a->Z, ctx)) |
| goto end; |
| if (!field_mul(group, n4, &b->Y, n0, ctx)) |
| goto end; |
| /* n4 = Y_b * Z_a^3 */ |
| } |
| |
| /* n5, n6 */ |
| if (!BN_mod_sub_quick(n5, n1, n3, p)) |
| goto end; |
| if (!BN_mod_sub_quick(n6, n2, n4, p)) |
| goto end; |
| /* n5 = n1 - n3 */ |
| /* n6 = n2 - n4 */ |
| |
| if (BN_is_zero(n5)) { |
| if (BN_is_zero(n6)) { |
| /* a is the same point as b */ |
| BN_CTX_end(ctx); |
| ret = EC_POINT_dbl(group, r, a, ctx); |
| ctx = NULL; |
| goto end; |
| } else { |
| /* a is the inverse of b */ |
| BN_zero(&r->Z); |
| r->Z_is_one = 0; |
| ret = 1; |
| goto end; |
| } |
| } |
| |
| /* 'n7', 'n8' */ |
| if (!BN_mod_add_quick(n1, n1, n3, p)) |
| goto end; |
| if (!BN_mod_add_quick(n2, n2, n4, p)) |
| goto end; |
| /* 'n7' = n1 + n3 */ |
| /* 'n8' = n2 + n4 */ |
| |
| /* Z_r */ |
| if (a->Z_is_one && b->Z_is_one) { |
| if (!BN_copy(&r->Z, n5)) |
| goto end; |
| } else { |
| if (a->Z_is_one) { |
| if (!BN_copy(n0, &b->Z)) |
| goto end; |
| } else if (b->Z_is_one) { |
| if (!BN_copy(n0, &a->Z)) |
| goto end; |
| } else { |
| if (!field_mul(group, n0, &a->Z, &b->Z, ctx)) |
| goto end; |
| } |
| if (!field_mul(group, &r->Z, n0, n5, ctx)) |
| goto end; |
| } |
| r->Z_is_one = 0; |
| /* Z_r = Z_a * Z_b * n5 */ |
| |
| /* X_r */ |
| if (!field_sqr(group, n0, n6, ctx)) |
| goto end; |
| if (!field_sqr(group, n4, n5, ctx)) |
| goto end; |
| if (!field_mul(group, n3, n1, n4, ctx)) |
| goto end; |
| if (!BN_mod_sub_quick(&r->X, n0, n3, p)) |
| goto end; |
| /* X_r = n6^2 - n5^2 * 'n7' */ |
| |
| /* 'n9' */ |
| if (!BN_mod_lshift1_quick(n0, &r->X, p)) |
| goto end; |
| if (!BN_mod_sub_quick(n0, n3, n0, p)) |
| goto end; |
| /* n9 = n5^2 * 'n7' - 2 * X_r */ |
| |
| /* Y_r */ |
| if (!field_mul(group, n0, n0, n6, ctx)) |
| goto end; |
| if (!field_mul(group, n5, n4, n5, ctx)) |
| goto end; /* now n5 is n5^3 */ |
| if (!field_mul(group, n1, n2, n5, ctx)) |
| goto end; |
| if (!BN_mod_sub_quick(n0, n0, n1, p)) |
| goto end; |
| if (BN_is_odd(n0)) |
| if (!BN_add(n0, n0, p)) |
| goto end; |
| /* now 0 <= n0 < 2*p, and n0 is even */ |
| if (!BN_rshift1(&r->Y, n0)) |
| goto end; |
| /* Y_r = (n6 * 'n9' - 'n8' * 'n5^3') / 2 */ |
| |
| ret = 1; |
| |
| end: |
| if (ctx) /* otherwise we already called BN_CTX_end */ |
| BN_CTX_end(ctx); |
| if (new_ctx != NULL) |
| BN_CTX_free(new_ctx); |
| return ret; |
| } |
| |
| int ec_GFp_simple_dbl(const EC_GROUP *group, EC_POINT *r, const EC_POINT *a, |
| BN_CTX *ctx) { |
| int (*field_mul)(const EC_GROUP *, BIGNUM *, const BIGNUM *, const BIGNUM *, |
| BN_CTX *); |
| int (*field_sqr)(const EC_GROUP *, BIGNUM *, const BIGNUM *, BN_CTX *); |
| const BIGNUM *p; |
| BN_CTX *new_ctx = NULL; |
| BIGNUM *n0, *n1, *n2, *n3; |
| int ret = 0; |
| |
| if (EC_POINT_is_at_infinity(group, a)) { |
| BN_zero(&r->Z); |
| r->Z_is_one = 0; |
| return 1; |
| } |
| |
| field_mul = group->meth->field_mul; |
| field_sqr = group->meth->field_sqr; |
| p = &group->field; |
| |
| if (ctx == NULL) { |
| ctx = new_ctx = BN_CTX_new(); |
| if (ctx == NULL) |
| return 0; |
| } |
| |
| BN_CTX_start(ctx); |
| n0 = BN_CTX_get(ctx); |
| n1 = BN_CTX_get(ctx); |
| n2 = BN_CTX_get(ctx); |
| n3 = BN_CTX_get(ctx); |
| if (n3 == NULL) |
| goto err; |
| |
| /* Note that in this function we must not read components of 'a' |
| * once we have written the corresponding components of 'r'. |
| * ('r' might the same as 'a'.) |
| */ |
| |
| /* n1 */ |
| if (a->Z_is_one) { |
| if (!field_sqr(group, n0, &a->X, ctx)) |
| goto err; |
| if (!BN_mod_lshift1_quick(n1, n0, p)) |
| goto err; |
| if (!BN_mod_add_quick(n0, n0, n1, p)) |
| goto err; |
| if (!BN_mod_add_quick(n1, n0, &group->a, p)) |
| goto err; |
| /* n1 = 3 * X_a^2 + a_curve */ |
| } else if (group->a_is_minus3) { |
| if (!field_sqr(group, n1, &a->Z, ctx)) |
| goto err; |
| if (!BN_mod_add_quick(n0, &a->X, n1, p)) |
| goto err; |
| if (!BN_mod_sub_quick(n2, &a->X, n1, p)) |
| goto err; |
| if (!field_mul(group, n1, n0, n2, ctx)) |
| goto err; |
| if (!BN_mod_lshift1_quick(n0, n1, p)) |
| goto err; |
| if (!BN_mod_add_quick(n1, n0, n1, p)) |
| goto err; |
| /* n1 = 3 * (X_a + Z_a^2) * (X_a - Z_a^2) |
| * = 3 * X_a^2 - 3 * Z_a^4 */ |
| } else { |
| if (!field_sqr(group, n0, &a->X, ctx)) |
| goto err; |
| if (!BN_mod_lshift1_quick(n1, n0, p)) |
| goto err; |
| if (!BN_mod_add_quick(n0, n0, n1, p)) |
| goto err; |
| if (!field_sqr(group, n1, &a->Z, ctx)) |
| goto err; |
| if (!field_sqr(group, n1, n1, ctx)) |
| goto err; |
| if (!field_mul(group, n1, n1, &group->a, ctx)) |
| goto err; |
| if (!BN_mod_add_quick(n1, n1, n0, p)) |
| goto err; |
| /* n1 = 3 * X_a^2 + a_curve * Z_a^4 */ |
| } |
| |
| /* Z_r */ |
| if (a->Z_is_one) { |
| if (!BN_copy(n0, &a->Y)) |
| goto err; |
| } else { |
| if (!field_mul(group, n0, &a->Y, &a->Z, ctx)) |
| goto err; |
| } |
| if (!BN_mod_lshift1_quick(&r->Z, n0, p)) |
| goto err; |
| r->Z_is_one = 0; |
| /* Z_r = 2 * Y_a * Z_a */ |
| |
| /* n2 */ |
| if (!field_sqr(group, n3, &a->Y, ctx)) |
| goto err; |
| if (!field_mul(group, n2, &a->X, n3, ctx)) |
| goto err; |
| if (!BN_mod_lshift_quick(n2, n2, 2, p)) |
| goto err; |
| /* n2 = 4 * X_a * Y_a^2 */ |
| |
| /* X_r */ |
| if (!BN_mod_lshift1_quick(n0, n2, p)) |
| goto err; |
| if (!field_sqr(group, &r->X, n1, ctx)) |
| goto err; |
| if (!BN_mod_sub_quick(&r->X, &r->X, n0, p)) |
| goto err; |
| /* X_r = n1^2 - 2 * n2 */ |
| |
| /* n3 */ |
| if (!field_sqr(group, n0, n3, ctx)) |
| goto err; |
| if (!BN_mod_lshift_quick(n3, n0, 3, p)) |
| goto err; |
| /* n3 = 8 * Y_a^4 */ |
| |
| /* Y_r */ |
| if (!BN_mod_sub_quick(n0, n2, &r->X, p)) |
| goto err; |
| if (!field_mul(group, n0, n1, n0, ctx)) |
| goto err; |
| if (!BN_mod_sub_quick(&r->Y, n0, n3, p)) |
| goto err; |
| /* Y_r = n1 * (n2 - X_r) - n3 */ |
| |
| ret = 1; |
| |
| err: |
| BN_CTX_end(ctx); |
| if (new_ctx != NULL) |
| BN_CTX_free(new_ctx); |
| return ret; |
| } |
| |
| int ec_GFp_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; |
| |
| return BN_usub(&point->Y, &group->field, &point->Y); |
| } |
| |
| int ec_GFp_simple_is_at_infinity(const EC_GROUP *group, const EC_POINT *point) { |
| return !point->Z_is_one && BN_is_zero(&point->Z); |
| } |
| |
| int ec_GFp_simple_is_on_curve(const EC_GROUP *group, const EC_POINT *point, |
| BN_CTX *ctx) { |
| int (*field_mul)(const EC_GROUP *, BIGNUM *, const BIGNUM *, const BIGNUM *, |
| BN_CTX *); |
| int (*field_sqr)(const EC_GROUP *, BIGNUM *, const BIGNUM *, BN_CTX *); |
| const BIGNUM *p; |
| BN_CTX *new_ctx = NULL; |
| BIGNUM *rh, *tmp, *Z4, *Z6; |
| int ret = -1; |
| |
| if (EC_POINT_is_at_infinity(group, point)) |
| return 1; |
| |
| field_mul = group->meth->field_mul; |
| field_sqr = group->meth->field_sqr; |
| p = &group->field; |
| |
| if (ctx == NULL) { |
| ctx = new_ctx = BN_CTX_new(); |
| if (ctx == NULL) |
| return -1; |
| } |
| |
| BN_CTX_start(ctx); |
| rh = BN_CTX_get(ctx); |
| tmp = BN_CTX_get(ctx); |
| Z4 = BN_CTX_get(ctx); |
| Z6 = BN_CTX_get(ctx); |
| if (Z6 == NULL) |
| goto err; |
| |
| /* We have a curve defined by a Weierstrass equation |
| * y^2 = x^3 + a*x + b. |
| * The point to consider is given in Jacobian projective coordinates |
| * where (X, Y, Z) represents (x, y) = (X/Z^2, Y/Z^3). |
| * Substituting this and multiplying by Z^6 transforms the above equation |
| * into |
| * Y^2 = X^3 + a*X*Z^4 + b*Z^6. |
| * To test this, we add up the right-hand side in 'rh'. |
| */ |
| |
| /* rh := X^2 */ |
| if (!field_sqr(group, rh, &point->X, ctx)) |
| goto err; |
| |
| if (!point->Z_is_one) { |
| if (!field_sqr(group, tmp, &point->Z, ctx)) |
| goto err; |
| if (!field_sqr(group, Z4, tmp, ctx)) |
| goto err; |
| if (!field_mul(group, Z6, Z4, tmp, ctx)) |
| goto err; |
| |
| /* rh := (rh + a*Z^4)*X */ |
| if (group->a_is_minus3) { |
| if (!BN_mod_lshift1_quick(tmp, Z4, p)) |
| goto err; |
| if (!BN_mod_add_quick(tmp, tmp, Z4, p)) |
| goto err; |
| if (!BN_mod_sub_quick(rh, rh, tmp, p)) |
| goto err; |
| if (!field_mul(group, rh, rh, &point->X, ctx)) |
| goto err; |
| } else { |
| if (!field_mul(group, tmp, Z4, &group->a, ctx)) |
| goto err; |
| if (!BN_mod_add_quick(rh, rh, tmp, p)) |
| goto err; |
| if (!field_mul(group, rh, rh, &point->X, ctx)) |
| goto err; |
| } |
| |
| /* rh := rh + b*Z^6 */ |
| if (!field_mul(group, tmp, &group->b, Z6, ctx)) |
| goto err; |
| if (!BN_mod_add_quick(rh, rh, tmp, p)) |
| goto err; |
| } else { |
| /* point->Z_is_one */ |
| |
| /* rh := (rh + a)*X */ |
| if (!BN_mod_add_quick(rh, rh, &group->a, p)) |
| goto err; |
| if (!field_mul(group, rh, rh, &point->X, ctx)) |
| goto err; |
| /* rh := rh + b */ |
| if (!BN_mod_add_quick(rh, rh, &group->b, p)) |
| goto err; |
| } |
| |
| /* 'lh' := Y^2 */ |
| if (!field_sqr(group, tmp, &point->Y, ctx)) |
| goto err; |
| |
| ret = (0 == BN_ucmp(tmp, rh)); |
| |
| err: |
| BN_CTX_end(ctx); |
| if (new_ctx != NULL) |
| BN_CTX_free(new_ctx); |
| return ret; |
| } |
| |
| int ec_GFp_simple_cmp(const EC_GROUP *group, const EC_POINT *a, |
| const EC_POINT *b, BN_CTX *ctx) { |
| /* return values: |
| * -1 error |
| * 0 equal (in affine coordinates) |
| * 1 not equal |
| */ |
| |
| int (*field_mul)(const EC_GROUP *, BIGNUM *, const BIGNUM *, const BIGNUM *, |
| BN_CTX *); |
| int (*field_sqr)(const EC_GROUP *, BIGNUM *, const BIGNUM *, BN_CTX *); |
| BN_CTX *new_ctx = NULL; |
| BIGNUM *tmp1, *tmp2, *Za23, *Zb23; |
| const BIGNUM *tmp1_, *tmp2_; |
| 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; |
| } |
| |
| field_mul = group->meth->field_mul; |
| field_sqr = group->meth->field_sqr; |
| |
| if (ctx == NULL) { |
| ctx = new_ctx = BN_CTX_new(); |
| if (ctx == NULL) |
| return -1; |
| } |
| |
| BN_CTX_start(ctx); |
| tmp1 = BN_CTX_get(ctx); |
| tmp2 = BN_CTX_get(ctx); |
| Za23 = BN_CTX_get(ctx); |
| Zb23 = BN_CTX_get(ctx); |
| if (Zb23 == NULL) |
| goto end; |
| |
| /* We have to decide whether |
| * (X_a/Z_a^2, Y_a/Z_a^3) = (X_b/Z_b^2, Y_b/Z_b^3), |
| * or equivalently, whether |
| * (X_a*Z_b^2, Y_a*Z_b^3) = (X_b*Z_a^2, Y_b*Z_a^3). |
| */ |
| |
| if (!b->Z_is_one) { |
| if (!field_sqr(group, Zb23, &b->Z, ctx)) |
| goto end; |
| if (!field_mul(group, tmp1, &a->X, Zb23, ctx)) |
| goto end; |
| tmp1_ = tmp1; |
| } else |
| tmp1_ = &a->X; |
| if (!a->Z_is_one) { |
| if (!field_sqr(group, Za23, &a->Z, ctx)) |
| goto end; |
| if (!field_mul(group, tmp2, &b->X, Za23, ctx)) |
| goto end; |
| tmp2_ = tmp2; |
| } else |
| tmp2_ = &b->X; |
| |
| /* compare X_a*Z_b^2 with X_b*Z_a^2 */ |
| if (BN_cmp(tmp1_, tmp2_) != 0) { |
| ret = 1; /* points differ */ |
| goto end; |
| } |
| |
| |
| if (!b->Z_is_one) { |
| if (!field_mul(group, Zb23, Zb23, &b->Z, ctx)) |
| goto end; |
| if (!field_mul(group, tmp1, &a->Y, Zb23, ctx)) |
| goto end; |
| /* tmp1_ = tmp1 */ |
| } else |
| tmp1_ = &a->Y; |
| if (!a->Z_is_one) { |
| if (!field_mul(group, Za23, Za23, &a->Z, ctx)) |
| goto end; |
| if (!field_mul(group, tmp2, &b->Y, Za23, ctx)) |
| goto end; |
| /* tmp2_ = tmp2 */ |
| } else |
| tmp2_ = &b->Y; |
| |
| /* compare Y_a*Z_b^3 with Y_b*Z_a^3 */ |
| if (BN_cmp(tmp1_, tmp2_) != 0) { |
| ret = 1; /* points differ */ |
| goto end; |
| } |
| |
| /* points are equal */ |
| ret = 0; |
| |
| end: |
| BN_CTX_end(ctx); |
| if (new_ctx != NULL) |
| BN_CTX_free(new_ctx); |
| return ret; |
| } |
| |
| int ec_GFp_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_GFp(group, point, x, y, ctx)) |
| goto err; |
| if (!EC_POINT_set_affine_coordinates_GFp(group, point, x, y, ctx)) |
| goto err; |
| if (!point->Z_is_one) { |
| OPENSSL_PUT_ERROR(EC, ec_GFp_simple_make_affine, ERR_R_INTERNAL_ERROR); |
| goto err; |
| } |
| |
| ret = 1; |
| |
| err: |
| BN_CTX_end(ctx); |
| if (new_ctx != NULL) |
| BN_CTX_free(new_ctx); |
| return ret; |
| } |
| |
| int ec_GFp_simple_points_make_affine(const EC_GROUP *group, size_t num, |
| EC_POINT *points[], BN_CTX *ctx) { |
| BN_CTX *new_ctx = NULL; |
| BIGNUM *tmp0, *tmp1; |
| size_t pow2 = 0; |
| BIGNUM **heap = NULL; |
| size_t i; |
| int ret = 0; |
| |
| if (num == 0) |
| return 1; |
| |
| if (ctx == NULL) { |
| ctx = new_ctx = BN_CTX_new(); |
| if (ctx == NULL) |
| return 0; |
| } |
| |
| BN_CTX_start(ctx); |
| tmp0 = BN_CTX_get(ctx); |
| tmp1 = BN_CTX_get(ctx); |
| if (tmp0 == NULL || tmp1 == NULL) |
| goto err; |
| |
| /* Before converting the individual points, compute inverses of all Z values. |
| * Modular inversion is rather slow, but luckily we can do with a single |
| * explicit inversion, plus about 3 multiplications per input value. |
| */ |
| |
| pow2 = 1; |
| while (num > pow2) |
| pow2 <<= 1; |
| /* Now pow2 is the smallest power of 2 satifsying pow2 >= num. |
| * We need twice that. */ |
| pow2 <<= 1; |
| |
| heap = OPENSSL_malloc(pow2 * sizeof heap[0]); |
| if (heap == NULL) |
| goto err; |
| |
| /* TODO(bmoeller): There is no reason to use this tree structure. |
| * We should instead proceed sequentially, exactly as in |
| * ec_GFp_nistp_points_make_affine_internal, which makes everything |
| * much simpler. */ |
| |
| /* The array is used as a binary tree, exactly as in heapsort: |
| * |
| * heap[1] |
| * heap[2] heap[3] |
| * heap[4] heap[5] heap[6] heap[7] |
| * heap[8]heap[9] heap[10]heap[11] heap[12]heap[13] heap[14] heap[15] |
| * |
| * We put the Z's in the last line; |
| * then we set each other node to the product of its two child-nodes (where |
| * empty or 0 entries are treated as ones); |
| * then we invert heap[1]; |
| * then we invert each other node by replacing it by the product of its |
| * parent (after inversion) and its sibling (before inversion). |
| */ |
| heap[0] = NULL; |
| for (i = pow2 / 2 - 1; i > 0; i--) |
| heap[i] = NULL; |
| for (i = 0; i < num; i++) |
| heap[pow2 / 2 + i] = &points[i]->Z; |
| for (i = pow2 / 2 + num; i < pow2; i++) |
| heap[i] = NULL; |
| |
| /* set each node to the product of its children */ |
| for (i = pow2 / 2 - 1; i > 0; i--) { |
| heap[i] = BN_new(); |
| if (heap[i] == NULL) |
| goto err; |
| |
| if (heap[2 * i] != NULL) { |
| if ((heap[2 * i + 1] == NULL) || BN_is_zero(heap[2 * i + 1])) { |
| if (!BN_copy(heap[i], heap[2 * i])) |
| goto err; |
| } else { |
| if (BN_is_zero(heap[2 * i])) { |
| if (!BN_copy(heap[i], heap[2 * i + 1])) |
| goto err; |
| } else { |
| if (!group->meth->field_mul(group, heap[i], heap[2 * i], |
| heap[2 * i + 1], ctx)) |
| goto err; |
| } |
| } |
| } |
| } |
| |
| /* invert heap[1] */ |
| if (!BN_is_zero(heap[1])) { |
| if (!BN_mod_inverse(heap[1], heap[1], &group->field, ctx)) { |
| OPENSSL_PUT_ERROR(EC, ec_GFp_simple_points_make_affine, ERR_R_BN_LIB); |
| goto err; |
| } |
| } |
| if (group->meth->field_encode != 0) { |
| /* in the Montgomery case, we just turned R*H (representing H) |
| * into 1/(R*H), but we need R*(1/H) (representing 1/H); |
| * i.e. we have need to multiply by the Montgomery factor twice */ |
| if (!group->meth->field_encode(group, heap[1], heap[1], ctx)) { |
| goto err; |
| } |
| if (!group->meth->field_encode(group, heap[1], heap[1], ctx)) { |
| goto err; |
| } |
| } |
| |
| /* set other heap[i]'s to their inverses */ |
| for (i = 2; i < pow2 / 2 + num; i += 2) { |
| /* i is even */ |
| if ((heap[i + 1] != NULL) && !BN_is_zero(heap[i + 1])) { |
| if (!BN_is_zero(heap[i])) { |
| if (!group->meth->field_mul(group, tmp0, heap[i / 2], heap[i + 1], ctx)) |
| goto err; |
| if (!group->meth->field_mul(group, tmp1, heap[i / 2], heap[i], ctx)) |
| goto err; |
| if (!BN_copy(heap[i], tmp0)) |
| goto err; |
| if (!BN_copy(heap[i + 1], tmp1)) |
| goto err; |
| } else { |
| if (!BN_copy(heap[i + 1], heap[i / 2])) |
| goto err; |
| } |
| } else { |
| if (!BN_copy(heap[i], heap[i / 2])) |
| goto err; |
| } |
| } |
| |
| /* we have replaced all non-zero Z's by their inverses, now fix up all the |
| * points */ |
| for (i = 0; i < num; i++) { |
| EC_POINT *p = points[i]; |
| |
| if (!BN_is_zero(&p->Z)) { |
| /* turn (X, Y, 1/Z) into (X/Z^2, Y/Z^3, 1) */ |
| |
| if (!group->meth->field_sqr(group, tmp1, &p->Z, ctx)) |
| goto err; |
| if (!group->meth->field_mul(group, &p->X, &p->X, tmp1, ctx)) |
| goto err; |
| |
| if (!group->meth->field_mul(group, tmp1, tmp1, &p->Z, ctx)) |
| goto err; |
| if (!group->meth->field_mul(group, &p->Y, &p->Y, tmp1, ctx)) |
| goto err; |
| |
| if (group->meth->field_set_to_one != 0) { |
| if (!group->meth->field_set_to_one(group, &p->Z, ctx)) |
| goto err; |
| } else { |
| if (!BN_one(&p->Z)) |
| goto err; |
| } |
| p->Z_is_one = 1; |
| } |
| } |
| |
| ret = 1; |
| |
| err: |
| BN_CTX_end(ctx); |
| if (new_ctx != NULL) |
| BN_CTX_free(new_ctx); |
| if (heap != NULL) { |
| /* heap[pow2/2] .. heap[pow2-1] have not been allocated locally! */ |
| for (i = pow2 / 2 - 1; i > 0; i--) { |
| if (heap[i] != NULL) |
| BN_clear_free(heap[i]); |
| } |
| OPENSSL_free(heap); |
| } |
| return ret; |
| } |
| |
| int ec_GFp_simple_field_mul(const EC_GROUP *group, BIGNUM *r, const BIGNUM *a, |
| const BIGNUM *b, BN_CTX *ctx) { |
| return BN_mod_mul(r, a, b, &group->field, ctx); |
| } |
| |
| int ec_GFp_simple_field_sqr(const EC_GROUP *group, BIGNUM *r, const BIGNUM *a, |
| BN_CTX *ctx) { |
| return BN_mod_sqr(r, a, &group->field, ctx); |
| } |