diff options
Diffstat (limited to 'crypto/ec/ecp_smpl.c')
| -rw-r--r-- | crypto/ec/ecp_smpl.c | 736 |
1 files changed, 481 insertions, 255 deletions
diff --git a/crypto/ec/ecp_smpl.c b/crypto/ec/ecp_smpl.c index e94a7d49368d..d0c5557ff4dd 100644 --- a/crypto/ec/ecp_smpl.c +++ b/crypto/ec/ecp_smpl.c @@ -1,75 +1,16 @@ -/* crypto/ec/ecp_smpl.c */ /* - * Includes code written by Lenka Fibikova <fibikova@exp-math.uni-essen.de> - * for the OpenSSL project. Includes code written by Bodo Moeller for the - * OpenSSL project. - */ -/* ==================================================================== - * Copyright (c) 1998-2002 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. + * Copyright 2001-2018 The OpenSSL Project Authors. All Rights Reserved. + * Copyright (c) 2002, Oracle and/or its affiliates. All rights reserved * - * 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 this software developed by SUN MICROSYSTEMS, INC., - * and contributed to the OpenSSL project. + * Licensed under the OpenSSL license (the "License"). You may not use + * this file except in compliance with the License. You can obtain a copy + * in the file LICENSE in the source distribution or at + * https://www.openssl.org/source/license.html */ #include <openssl/err.h> #include <openssl/symhacks.h> -#ifdef OPENSSL_FIPS -# include <openssl/fips.h> -#endif - #include "ec_lcl.h" const EC_METHOD *EC_GFp_simple_method(void) @@ -84,6 +25,7 @@ const EC_METHOD *EC_GFp_simple_method(void) ec_GFp_simple_group_set_curve, ec_GFp_simple_group_get_curve, ec_GFp_simple_group_get_degree, + ec_group_simple_order_bits, ec_GFp_simple_group_check_discriminant, ec_GFp_simple_point_init, ec_GFp_simple_point_finish, @@ -111,14 +53,23 @@ const EC_METHOD *EC_GFp_simple_method(void) 0 /* field_div */ , 0 /* field_encode */ , 0 /* field_decode */ , - 0 /* field_set_to_one */ + 0, /* field_set_to_one */ + ec_key_simple_priv2oct, + ec_key_simple_oct2priv, + 0, /* set private */ + ec_key_simple_generate_key, + ec_key_simple_check_key, + ec_key_simple_generate_public_key, + 0, /* keycopy */ + 0, /* keyfinish */ + ecdh_simple_compute_key, + 0, /* field_inverse_mod_ord */ + ec_GFp_simple_blind_coordinates, + ec_GFp_simple_ladder_pre, + ec_GFp_simple_ladder_step, + ec_GFp_simple_ladder_post }; -#ifdef OPENSSL_FIPS - if (FIPS_mode()) - return fips_ec_gfp_simple_method(); -#endif - return &ret; } @@ -138,34 +89,40 @@ const EC_METHOD *EC_GFp_simple_method(void) int ec_GFp_simple_group_init(EC_GROUP *group) { - BN_init(&group->field); - BN_init(&group->a); - BN_init(&group->b); + group->field = BN_new(); + group->a = BN_new(); + group->b = BN_new(); + if (group->field == NULL || group->a == NULL || group->b == NULL) { + BN_free(group->field); + BN_free(group->a); + BN_free(group->b); + return 0; + } 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); + 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); + 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)) + if (!BN_copy(dest->field, src->field)) return 0; - if (!BN_copy(&dest->a, &src->a)) + if (!BN_copy(dest->a, src->a)) return 0; - if (!BN_copy(&dest->b, &src->b)) + if (!BN_copy(dest->b, src->b)) return 0; dest->a_is_minus3 = src->a_is_minus3; @@ -199,37 +156,36 @@ int ec_GFp_simple_group_set_curve(EC_GROUP *group, goto err; /* group->field */ - if (!BN_copy(&group->field, p)) + if (!BN_copy(group->field, p)) goto err; - BN_set_negative(&group->field, 0); + 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)) + if (!group->meth->field_encode(group, group->a, tmp_a, ctx)) goto err; - } else if (!BN_copy(&group->a, tmp_a)) + } else if (!BN_copy(group->a, tmp_a)) goto err; /* group->b */ - if (!BN_nnmod(&group->b, b, p, ctx)) + 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)) + 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)); + 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); + BN_CTX_free(new_ctx); return ret; } @@ -240,7 +196,7 @@ int ec_GFp_simple_group_get_curve(const EC_GROUP *group, BIGNUM *p, BIGNUM *a, BN_CTX *new_ctx = NULL; if (p != NULL) { - if (!BN_copy(p, &group->field)) + if (!BN_copy(p, group->field)) return 0; } @@ -252,20 +208,20 @@ int ec_GFp_simple_group_get_curve(const EC_GROUP *group, BIGNUM *p, BIGNUM *a, return 0; } if (a != NULL) { - if (!group->meth->field_decode(group, a, &group->a, ctx)) + 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)) + if (!group->meth->field_decode(group, b, group->b, ctx)) goto err; } } else { if (a != NULL) { - if (!BN_copy(a, &group->a)) + if (!BN_copy(a, group->a)) goto err; } if (b != NULL) { - if (!BN_copy(b, &group->b)) + if (!BN_copy(b, group->b)) goto err; } } @@ -274,21 +230,20 @@ int ec_GFp_simple_group_get_curve(const EC_GROUP *group, BIGNUM *p, BIGNUM *a, ret = 1; err: - if (new_ctx) - BN_CTX_free(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); + 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; + const BIGNUM *p = group->field; BN_CTX *new_ctx = NULL; if (ctx == NULL) { @@ -309,14 +264,14 @@ int ec_GFp_simple_group_check_discriminant(const EC_GROUP *group, BN_CTX *ctx) goto err; if (group->meth->field_decode) { - if (!group->meth->field_decode(group, a, &group->a, ctx)) + if (!group->meth->field_decode(group, a, group->a, ctx)) goto err; - if (!group->meth->field_decode(group, b, &group->b, ctx)) + if (!group->meth->field_decode(group, b, group->b, ctx)) goto err; } else { - if (!BN_copy(a, &group->a)) + if (!BN_copy(a, group->a)) goto err; - if (!BN_copy(b, &group->b)) + if (!BN_copy(b, group->b)) goto err; } @@ -353,45 +308,51 @@ int ec_GFp_simple_group_check_discriminant(const EC_GROUP *group, BN_CTX *ctx) err: if (ctx != NULL) BN_CTX_end(ctx); - if (new_ctx != NULL) - BN_CTX_free(new_ctx); + 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->X = BN_new(); + point->Y = BN_new(); + point->Z = BN_new(); point->Z_is_one = 0; + if (point->X == NULL || point->Y == NULL || point->Z == NULL) { + BN_free(point->X); + BN_free(point->Y); + BN_free(point->Z); + return 0; + } return 1; } void ec_GFp_simple_point_finish(EC_POINT *point) { - BN_free(&point->X); - BN_free(&point->Y); - BN_free(&point->Z); + 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); + 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)) + if (!BN_copy(dest->X, src->X)) return 0; - if (!BN_copy(&dest->Y, &src->Y)) + if (!BN_copy(dest->Y, src->Y)) return 0; - if (!BN_copy(&dest->Z, &src->Z)) + if (!BN_copy(dest->Z, src->Z)) return 0; dest->Z_is_one = src->Z_is_one; + dest->curve_name = src->curve_name; return 1; } @@ -400,7 +361,7 @@ int ec_GFp_simple_point_set_to_infinity(const EC_GROUP *group, EC_POINT *point) { point->Z_is_one = 0; - BN_zero(&point->Z); + BN_zero(point->Z); return 1; } @@ -421,19 +382,19 @@ int ec_GFp_simple_set_Jprojective_coordinates_GFp(const EC_GROUP *group, } if (x != NULL) { - if (!BN_nnmod(&point->X, x, &group->field, ctx)) + 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)) + 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)) + 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)) + if (!group->meth->field_encode(group, point->Y, point->Y, ctx)) goto err; } } @@ -441,16 +402,16 @@ int ec_GFp_simple_set_Jprojective_coordinates_GFp(const EC_GROUP *group, if (z != NULL) { int Z_is_one; - if (!BN_nnmod(&point->Z, z, &group->field, ctx)) + if (!BN_nnmod(point->Z, z, group->field, ctx)) goto err; - Z_is_one = BN_is_one(&point->Z); + 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)) + 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)) + meth->field_encode(group, point->Z, point->Z, ctx)) goto err; } } @@ -460,8 +421,7 @@ int ec_GFp_simple_set_Jprojective_coordinates_GFp(const EC_GROUP *group, ret = 1; err: - if (new_ctx != NULL) - BN_CTX_free(new_ctx); + BN_CTX_free(new_ctx); return ret; } @@ -481,28 +441,28 @@ int ec_GFp_simple_get_Jprojective_coordinates_GFp(const EC_GROUP *group, } if (x != NULL) { - if (!group->meth->field_decode(group, x, &point->X, ctx)) + 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)) + 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)) + if (!group->meth->field_decode(group, z, point->Z, ctx)) goto err; } } else { if (x != NULL) { - if (!BN_copy(x, &point->X)) + if (!BN_copy(x, point->X)) goto err; } if (y != NULL) { - if (!BN_copy(y, &point->Y)) + if (!BN_copy(y, point->Y)) goto err; } if (z != NULL) { - if (!BN_copy(z, &point->Z)) + if (!BN_copy(z, point->Z)) goto err; } } @@ -510,8 +470,7 @@ int ec_GFp_simple_get_Jprojective_coordinates_GFp(const EC_GROUP *group, ret = 1; err: - if (new_ctx != NULL) - BN_CTX_free(new_ctx); + BN_CTX_free(new_ctx); return ret; } @@ -566,35 +525,35 @@ int ec_GFp_simple_point_get_affine_coordinates(const EC_GROUP *group, /* 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)) + if (!group->meth->field_decode(group, Z, point->Z, ctx)) goto err; Z_ = Z; } else { - Z_ = &point->Z; + 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)) + 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)) + if (!group->meth->field_decode(group, y, point->Y, ctx)) goto err; } } else { if (x != NULL) { - if (!BN_copy(x, &point->X)) + if (!BN_copy(x, point->X)) goto err; } if (y != NULL) { - if (!BN_copy(y, &point->Y)) + if (!BN_copy(y, point->Y)) goto err; } } } else { - if (!BN_mod_inverse(Z_1, Z_, &group->field, ctx)) { + if (!BN_mod_inverse(Z_1, Z_, group->field, ctx)) { ECerr(EC_F_EC_GFP_SIMPLE_POINT_GET_AFFINE_COORDINATES, ERR_R_BN_LIB); goto err; @@ -605,7 +564,7 @@ int ec_GFp_simple_point_get_affine_coordinates(const EC_GROUP *group, 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)) + if (!BN_mod_sqr(Z_2, Z_1, group->field, ctx)) goto err; } @@ -614,7 +573,7 @@ int ec_GFp_simple_point_get_affine_coordinates(const EC_GROUP *group, * 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)) + if (!group->meth->field_mul(group, x, point->X, Z_2, ctx)) goto err; } @@ -626,7 +585,7 @@ int ec_GFp_simple_point_get_affine_coordinates(const EC_GROUP *group, 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)) + if (!BN_mod_mul(Z_3, Z_2, Z_1, group->field, ctx)) goto err; } @@ -634,7 +593,7 @@ int ec_GFp_simple_point_get_affine_coordinates(const EC_GROUP *group, * 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)) + if (!group->meth->field_mul(group, y, point->Y, Z_3, ctx)) goto err; } } @@ -643,8 +602,7 @@ int ec_GFp_simple_point_get_affine_coordinates(const EC_GROUP *group, err: BN_CTX_end(ctx); - if (new_ctx != NULL) - BN_CTX_free(new_ctx); + BN_CTX_free(new_ctx); return ret; } @@ -668,7 +626,7 @@ int ec_GFp_simple_add(const EC_GROUP *group, EC_POINT *r, const EC_POINT *a, field_mul = group->meth->field_mul; field_sqr = group->meth->field_sqr; - p = &group->field; + p = group->field; if (ctx == NULL) { ctx = new_ctx = BN_CTX_new(); @@ -695,44 +653,44 @@ int ec_GFp_simple_add(const EC_GROUP *group, EC_POINT *r, const EC_POINT *a, /* n1, n2 */ if (b->Z_is_one) { - if (!BN_copy(n1, &a->X)) + if (!BN_copy(n1, a->X)) goto end; - if (!BN_copy(n2, &a->Y)) + if (!BN_copy(n2, a->Y)) goto end; /* n1 = X_a */ /* n2 = Y_a */ } else { - if (!field_sqr(group, n0, &b->Z, ctx)) + if (!field_sqr(group, n0, b->Z, ctx)) goto end; - if (!field_mul(group, n1, &a->X, n0, ctx)) + 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)) + if (!field_mul(group, n0, n0, b->Z, ctx)) goto end; - if (!field_mul(group, n2, &a->Y, n0, ctx)) + 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)) + if (!BN_copy(n3, b->X)) goto end; - if (!BN_copy(n4, &b->Y)) + if (!BN_copy(n4, b->Y)) goto end; /* n3 = X_b */ /* n4 = Y_b */ } else { - if (!field_sqr(group, n0, &a->Z, ctx)) + if (!field_sqr(group, n0, a->Z, ctx)) goto end; - if (!field_mul(group, n3, &b->X, n0, ctx)) + 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)) + if (!field_mul(group, n0, n0, a->Z, ctx)) goto end; - if (!field_mul(group, n4, &b->Y, n0, ctx)) + if (!field_mul(group, n4, b->Y, n0, ctx)) goto end; /* n4 = Y_b * Z_a^3 */ } @@ -754,7 +712,7 @@ int ec_GFp_simple_add(const EC_GROUP *group, EC_POINT *r, const EC_POINT *a, goto end; } else { /* a is the inverse of b */ - BN_zero(&r->Z); + BN_zero(r->Z); r->Z_is_one = 0; ret = 1; goto end; @@ -771,20 +729,20 @@ int ec_GFp_simple_add(const EC_GROUP *group, EC_POINT *r, const EC_POINT *a, /* Z_r */ if (a->Z_is_one && b->Z_is_one) { - if (!BN_copy(&r->Z, n5)) + if (!BN_copy(r->Z, n5)) goto end; } else { if (a->Z_is_one) { - if (!BN_copy(n0, &b->Z)) + if (!BN_copy(n0, b->Z)) goto end; } else if (b->Z_is_one) { - if (!BN_copy(n0, &a->Z)) + if (!BN_copy(n0, a->Z)) goto end; } else { - if (!field_mul(group, n0, &a->Z, &b->Z, ctx)) + if (!field_mul(group, n0, a->Z, b->Z, ctx)) goto end; } - if (!field_mul(group, &r->Z, n0, n5, ctx)) + if (!field_mul(group, r->Z, n0, n5, ctx)) goto end; } r->Z_is_one = 0; @@ -797,12 +755,12 @@ int ec_GFp_simple_add(const EC_GROUP *group, EC_POINT *r, const EC_POINT *a, goto end; if (!field_mul(group, n3, n1, n4, ctx)) goto end; - if (!BN_mod_sub_quick(&r->X, n0, n3, p)) + 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)) + if (!BN_mod_lshift1_quick(n0, r->X, p)) goto end; if (!BN_mod_sub_quick(n0, n3, n0, p)) goto end; @@ -821,7 +779,7 @@ int ec_GFp_simple_add(const EC_GROUP *group, EC_POINT *r, const EC_POINT *a, if (!BN_add(n0, n0, p)) goto end; /* now 0 <= n0 < 2*p, and n0 is even */ - if (!BN_rshift1(&r->Y, n0)) + if (!BN_rshift1(r->Y, n0)) goto end; /* Y_r = (n6 * 'n9' - 'n8' * 'n5^3') / 2 */ @@ -830,8 +788,7 @@ int ec_GFp_simple_add(const EC_GROUP *group, EC_POINT *r, const EC_POINT *a, end: if (ctx) /* otherwise we already called BN_CTX_end */ BN_CTX_end(ctx); - if (new_ctx != NULL) - BN_CTX_free(new_ctx); + BN_CTX_free(new_ctx); return ret; } @@ -847,14 +804,14 @@ int ec_GFp_simple_dbl(const EC_GROUP *group, EC_POINT *r, const EC_POINT *a, int ret = 0; if (EC_POINT_is_at_infinity(group, a)) { - BN_zero(&r->Z); + 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; + p = group->field; if (ctx == NULL) { ctx = new_ctx = BN_CTX_new(); @@ -878,21 +835,21 @@ int ec_GFp_simple_dbl(const EC_GROUP *group, EC_POINT *r, const EC_POINT *a, /* n1 */ if (a->Z_is_one) { - if (!field_sqr(group, n0, &a->X, ctx)) + 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)) + 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)) + if (!field_sqr(group, n1, a->Z, ctx)) goto err; - if (!BN_mod_add_quick(n0, &a->X, n1, p)) + if (!BN_mod_add_quick(n0, a->X, n1, p)) goto err; - if (!BN_mod_sub_quick(n2, &a->X, n1, p)) + if (!BN_mod_sub_quick(n2, a->X, n1, p)) goto err; if (!field_mul(group, n1, n0, n2, ctx)) goto err; @@ -905,17 +862,17 @@ int ec_GFp_simple_dbl(const EC_GROUP *group, EC_POINT *r, const EC_POINT *a, * = 3 * X_a^2 - 3 * Z_a^4 */ } else { - if (!field_sqr(group, n0, &a->X, ctx)) + 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)) + 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)) + if (!field_mul(group, n1, n1, group->a, ctx)) goto err; if (!BN_mod_add_quick(n1, n1, n0, p)) goto err; @@ -924,21 +881,21 @@ int ec_GFp_simple_dbl(const EC_GROUP *group, EC_POINT *r, const EC_POINT *a, /* Z_r */ if (a->Z_is_one) { - if (!BN_copy(n0, &a->Y)) + if (!BN_copy(n0, a->Y)) goto err; } else { - if (!field_mul(group, n0, &a->Y, &a->Z, ctx)) + if (!field_mul(group, n0, a->Y, a->Z, ctx)) goto err; } - if (!BN_mod_lshift1_quick(&r->Z, n0, p)) + 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)) + if (!field_sqr(group, n3, a->Y, ctx)) goto err; - if (!field_mul(group, n2, &a->X, n3, ctx)) + if (!field_mul(group, n2, a->X, n3, ctx)) goto err; if (!BN_mod_lshift_quick(n2, n2, 2, p)) goto err; @@ -947,9 +904,9 @@ int ec_GFp_simple_dbl(const EC_GROUP *group, EC_POINT *r, const EC_POINT *a, /* X_r */ if (!BN_mod_lshift1_quick(n0, n2, p)) goto err; - if (!field_sqr(group, &r->X, n1, ctx)) + if (!field_sqr(group, r->X, n1, ctx)) goto err; - if (!BN_mod_sub_quick(&r->X, &r->X, n0, p)) + if (!BN_mod_sub_quick(r->X, r->X, n0, p)) goto err; /* X_r = n1^2 - 2 * n2 */ @@ -961,11 +918,11 @@ int ec_GFp_simple_dbl(const EC_GROUP *group, EC_POINT *r, const EC_POINT *a, /* n3 = 8 * Y_a^4 */ /* Y_r */ - if (!BN_mod_sub_quick(n0, n2, &r->X, p)) + 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)) + if (!BN_mod_sub_quick(r->Y, n0, n3, p)) goto err; /* Y_r = n1 * (n2 - X_r) - n3 */ @@ -973,23 +930,22 @@ int ec_GFp_simple_dbl(const EC_GROUP *group, EC_POINT *r, const EC_POINT *a, err: BN_CTX_end(ctx); - if (new_ctx != NULL) - BN_CTX_free(new_ctx); + 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)) + 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); + 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 BN_is_zero(&point->Z); + return BN_is_zero(point->Z); } int ec_GFp_simple_is_on_curve(const EC_GROUP *group, const EC_POINT *point, @@ -1008,7 +964,7 @@ int ec_GFp_simple_is_on_curve(const EC_GROUP *group, const EC_POINT *point, field_mul = group->meth->field_mul; field_sqr = group->meth->field_sqr; - p = &group->field; + p = group->field; if (ctx == NULL) { ctx = new_ctx = BN_CTX_new(); @@ -1035,11 +991,11 @@ int ec_GFp_simple_is_on_curve(const EC_GROUP *group, const EC_POINT *point, */ /* rh := X^2 */ - if (!field_sqr(group, rh, &point->X, ctx)) + if (!field_sqr(group, rh, point->X, ctx)) goto err; if (!point->Z_is_one) { - if (!field_sqr(group, tmp, &point->Z, ctx)) + if (!field_sqr(group, tmp, point->Z, ctx)) goto err; if (!field_sqr(group, Z4, tmp, ctx)) goto err; @@ -1054,19 +1010,19 @@ int ec_GFp_simple_is_on_curve(const EC_GROUP *group, const EC_POINT *point, goto err; if (!BN_mod_sub_quick(rh, rh, tmp, p)) goto err; - if (!field_mul(group, rh, rh, &point->X, ctx)) + if (!field_mul(group, rh, rh, point->X, ctx)) goto err; } else { - if (!field_mul(group, tmp, Z4, &group->a, ctx)) + 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)) + 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)) + if (!field_mul(group, tmp, group->b, Z6, ctx)) goto err; if (!BN_mod_add_quick(rh, rh, tmp, p)) goto err; @@ -1074,25 +1030,24 @@ int ec_GFp_simple_is_on_curve(const EC_GROUP *group, const EC_POINT *point, /* point->Z_is_one */ /* rh := (rh + a)*X */ - if (!BN_mod_add_quick(rh, rh, &group->a, p)) + if (!BN_mod_add_quick(rh, rh, group->a, p)) goto err; - if (!field_mul(group, rh, rh, &point->X, ctx)) + if (!field_mul(group, rh, rh, point->X, ctx)) goto err; /* rh := rh + b */ - if (!BN_mod_add_quick(rh, rh, &group->b, p)) + if (!BN_mod_add_quick(rh, rh, group->b, p)) goto err; } /* 'lh' := Y^2 */ - if (!field_sqr(group, tmp, &point->Y, ctx)) + 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); + BN_CTX_free(new_ctx); return ret; } @@ -1122,8 +1077,7 @@ int ec_GFp_simple_cmp(const EC_GROUP *group, const EC_POINT *a, 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; + return ((BN_cmp(a->X, b->X) == 0) && BN_cmp(a->Y, b->Y) == 0) ? 0 : 1; } field_mul = group->meth->field_mul; @@ -1151,21 +1105,21 @@ int ec_GFp_simple_cmp(const EC_GROUP *group, const EC_POINT *a, */ if (!b->Z_is_one) { - if (!field_sqr(group, Zb23, &b->Z, ctx)) + if (!field_sqr(group, Zb23, b->Z, ctx)) goto end; - if (!field_mul(group, tmp1, &a->X, Zb23, ctx)) + if (!field_mul(group, tmp1, a->X, Zb23, ctx)) goto end; tmp1_ = tmp1; } else - tmp1_ = &a->X; + tmp1_ = a->X; if (!a->Z_is_one) { - if (!field_sqr(group, Za23, &a->Z, ctx)) + if (!field_sqr(group, Za23, a->Z, ctx)) goto end; - if (!field_mul(group, tmp2, &b->X, Za23, ctx)) + if (!field_mul(group, tmp2, b->X, Za23, ctx)) goto end; tmp2_ = tmp2; } else - tmp2_ = &b->X; + tmp2_ = b->X; /* compare X_a*Z_b^2 with X_b*Z_a^2 */ if (BN_cmp(tmp1_, tmp2_) != 0) { @@ -1174,21 +1128,21 @@ int ec_GFp_simple_cmp(const EC_GROUP *group, const EC_POINT *a, } if (!b->Z_is_one) { - if (!field_mul(group, Zb23, Zb23, &b->Z, ctx)) + if (!field_mul(group, Zb23, Zb23, b->Z, ctx)) goto end; - if (!field_mul(group, tmp1, &a->Y, Zb23, ctx)) + if (!field_mul(group, tmp1, a->Y, Zb23, ctx)) goto end; /* tmp1_ = tmp1 */ } else - tmp1_ = &a->Y; + tmp1_ = a->Y; if (!a->Z_is_one) { - if (!field_mul(group, Za23, Za23, &a->Z, ctx)) + if (!field_mul(group, Za23, Za23, a->Z, ctx)) goto end; - if (!field_mul(group, tmp2, &b->Y, Za23, ctx)) + if (!field_mul(group, tmp2, b->Y, Za23, ctx)) goto end; /* tmp2_ = tmp2 */ } else - tmp2_ = &b->Y; + tmp2_ = b->Y; /* compare Y_a*Z_b^3 with Y_b*Z_a^3 */ if (BN_cmp(tmp1_, tmp2_) != 0) { @@ -1201,8 +1155,7 @@ int ec_GFp_simple_cmp(const EC_GROUP *group, const EC_POINT *a, end: BN_CTX_end(ctx); - if (new_ctx != NULL) - BN_CTX_free(new_ctx); + BN_CTX_free(new_ctx); return ret; } @@ -1228,9 +1181,9 @@ int ec_GFp_simple_make_affine(const EC_GROUP *group, EC_POINT *point, if (y == NULL) goto err; - if (!EC_POINT_get_affine_coordinates_GFp(group, point, x, y, ctx)) + if (!EC_POINT_get_affine_coordinates(group, point, x, y, ctx)) goto err; - if (!EC_POINT_set_affine_coordinates_GFp(group, point, x, y, ctx)) + if (!EC_POINT_set_affine_coordinates(group, point, x, y, ctx)) goto err; if (!point->Z_is_one) { ECerr(EC_F_EC_GFP_SIMPLE_MAKE_AFFINE, ERR_R_INTERNAL_ERROR); @@ -1241,8 +1194,7 @@ int ec_GFp_simple_make_affine(const EC_GROUP *group, EC_POINT *point, err: BN_CTX_end(ctx); - if (new_ctx != NULL) - BN_CTX_free(new_ctx); + BN_CTX_free(new_ctx); return ret; } @@ -1267,7 +1219,7 @@ int ec_GFp_simple_points_make_affine(const EC_GROUP *group, size_t num, BN_CTX_start(ctx); tmp = BN_CTX_get(ctx); tmp_Z = BN_CTX_get(ctx); - if (tmp == NULL || tmp_Z == NULL) + if (tmp_Z == NULL) goto err; prod_Z = OPENSSL_malloc(num * sizeof(prod_Z[0])); @@ -1284,8 +1236,8 @@ int ec_GFp_simple_points_make_affine(const EC_GROUP *group, size_t num, * skipping any zero-valued inputs (pretend that they're 1). */ - if (!BN_is_zero(&points[0]->Z)) { - if (!BN_copy(prod_Z[0], &points[0]->Z)) + if (!BN_is_zero(points[0]->Z)) { + if (!BN_copy(prod_Z[0], points[0]->Z)) goto err; } else { if (group->meth->field_set_to_one != 0) { @@ -1298,9 +1250,10 @@ int ec_GFp_simple_points_make_affine(const EC_GROUP *group, size_t num, } for (i = 1; i < num; i++) { - if (!BN_is_zero(&points[i]->Z)) { - if (!group->meth->field_mul(group, prod_Z[i], prod_Z[i - 1], - &points[i]->Z, ctx)) + if (!BN_is_zero(points[i]->Z)) { + if (!group-> + meth->field_mul(group, prod_Z[i], prod_Z[i - 1], points[i]->Z, + ctx)) goto err; } else { if (!BN_copy(prod_Z[i], prod_Z[i - 1])) @@ -1313,7 +1266,7 @@ int ec_GFp_simple_points_make_affine(const EC_GROUP *group, size_t num, * points[i]->Z by its inverse. */ - if (!BN_mod_inverse(tmp, prod_Z[num - 1], &group->field, ctx)) { + if (!BN_mod_inverse(tmp, prod_Z[num - 1], group->field, ctx)) { ECerr(EC_F_EC_GFP_SIMPLE_POINTS_MAKE_AFFINE, ERR_R_BN_LIB); goto err; } @@ -1334,7 +1287,7 @@ int ec_GFp_simple_points_make_affine(const EC_GROUP *group, size_t num, * Loop invariant: tmp is the product of the inverses of points[0]->Z * .. points[i]->Z (zero-valued inputs skipped). */ - if (!BN_is_zero(&points[i]->Z)) { + if (!BN_is_zero(points[i]->Z)) { /* * Set tmp_Z to the inverse of points[i]->Z (as product of Z * inverses 0 .. i, Z values 0 .. i - 1). @@ -1345,17 +1298,17 @@ int ec_GFp_simple_points_make_affine(const EC_GROUP *group, size_t num, /* * Update tmp to satisfy the loop invariant for i - 1. */ - if (!group->meth->field_mul(group, tmp, tmp, &points[i]->Z, ctx)) + if (!group->meth->field_mul(group, tmp, tmp, points[i]->Z, ctx)) goto err; /* Replace points[i]->Z by its inverse. */ - if (!BN_copy(&points[i]->Z, tmp_Z)) + if (!BN_copy(points[i]->Z, tmp_Z)) goto err; } } - if (!BN_is_zero(&points[0]->Z)) { + if (!BN_is_zero(points[0]->Z)) { /* Replace points[0]->Z by its inverse. */ - if (!BN_copy(&points[0]->Z, tmp)) + if (!BN_copy(points[0]->Z, tmp)) goto err; } @@ -1364,24 +1317,24 @@ int ec_GFp_simple_points_make_affine(const EC_GROUP *group, size_t num, for (i = 0; i < num; i++) { EC_POINT *p = points[i]; - if (!BN_is_zero(&p->Z)) { + 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, tmp, &p->Z, ctx)) + if (!group->meth->field_sqr(group, tmp, p->Z, ctx)) goto err; - if (!group->meth->field_mul(group, &p->X, &p->X, tmp, ctx)) + if (!group->meth->field_mul(group, p->X, p->X, tmp, ctx)) goto err; - if (!group->meth->field_mul(group, tmp, tmp, &p->Z, ctx)) + if (!group->meth->field_mul(group, tmp, tmp, p->Z, ctx)) goto err; - if (!group->meth->field_mul(group, &p->Y, &p->Y, tmp, ctx)) + if (!group->meth->field_mul(group, p->Y, p->Y, tmp, ctx)) goto err; if (group->meth->field_set_to_one != 0) { - if (!group->meth->field_set_to_one(group, &p->Z, ctx)) + if (!group->meth->field_set_to_one(group, p->Z, ctx)) goto err; } else { - if (!BN_one(&p->Z)) + if (!BN_one(p->Z)) goto err; } p->Z_is_one = 1; @@ -1392,8 +1345,7 @@ int ec_GFp_simple_points_make_affine(const EC_GROUP *group, size_t num, err: BN_CTX_end(ctx); - if (new_ctx != NULL) - BN_CTX_free(new_ctx); + BN_CTX_free(new_ctx); if (prod_Z != NULL) { for (i = 0; i < num; i++) { if (prod_Z[i] == NULL) @@ -1408,11 +1360,285 @@ int ec_GFp_simple_points_make_affine(const EC_GROUP *group, size_t num, 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); + 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); + return BN_mod_sqr(r, a, group->field, ctx); +} + +/*- + * Apply randomization of EC point projective coordinates: + * + * (X, Y ,Z ) = (lambda^2*X, lambda^3*Y, lambda*Z) + * lambda = [1,group->field) + * + */ +int ec_GFp_simple_blind_coordinates(const EC_GROUP *group, EC_POINT *p, + BN_CTX *ctx) +{ + int ret = 0; + BIGNUM *lambda = NULL; + BIGNUM *temp = NULL; + + BN_CTX_start(ctx); + lambda = BN_CTX_get(ctx); + temp = BN_CTX_get(ctx); + if (temp == NULL) { + ECerr(EC_F_EC_GFP_SIMPLE_BLIND_COORDINATES, ERR_R_MALLOC_FAILURE); + goto err; + } + + /* make sure lambda is not zero */ + do { + if (!BN_priv_rand_range(lambda, group->field)) { + ECerr(EC_F_EC_GFP_SIMPLE_BLIND_COORDINATES, ERR_R_BN_LIB); + goto err; + } + } while (BN_is_zero(lambda)); + + /* if field_encode defined convert between representations */ + if (group->meth->field_encode != NULL + && !group->meth->field_encode(group, lambda, lambda, ctx)) + goto err; + if (!group->meth->field_mul(group, p->Z, p->Z, lambda, ctx)) + goto err; + if (!group->meth->field_sqr(group, temp, lambda, ctx)) + goto err; + if (!group->meth->field_mul(group, p->X, p->X, temp, ctx)) + goto err; + if (!group->meth->field_mul(group, temp, temp, lambda, ctx)) + goto err; + if (!group->meth->field_mul(group, p->Y, p->Y, temp, ctx)) + goto err; + p->Z_is_one = 0; + + ret = 1; + + err: + BN_CTX_end(ctx); + return ret; +} + +/*- + * Set s := p, r := 2p. + * + * For doubling we use Formula 3 from Izu-Takagi "A fast parallel elliptic curve + * multiplication resistant against side channel attacks" appendix, as described + * at + * https://hyperelliptic.org/EFD/g1p/auto-shortw-xz.html#doubling-dbl-2002-it-2 + * + * The input point p will be in randomized Jacobian projective coords: + * x = X/Z**2, y=Y/Z**3 + * + * The output points p, s, and r are converted to standard (homogeneous) + * projective coords: + * x = X/Z, y=Y/Z + */ +int ec_GFp_simple_ladder_pre(const EC_GROUP *group, + EC_POINT *r, EC_POINT *s, + EC_POINT *p, BN_CTX *ctx) +{ + BIGNUM *t1, *t2, *t3, *t4, *t5, *t6 = NULL; + + t1 = r->Z; + t2 = r->Y; + t3 = s->X; + t4 = r->X; + t5 = s->Y; + t6 = s->Z; + + /* convert p: (X,Y,Z) -> (XZ,Y,Z**3) */ + if (!group->meth->field_mul(group, p->X, p->X, p->Z, ctx) + || !group->meth->field_sqr(group, t1, p->Z, ctx) + || !group->meth->field_mul(group, p->Z, p->Z, t1, ctx) + /* r := 2p */ + || !group->meth->field_sqr(group, t2, p->X, ctx) + || !group->meth->field_sqr(group, t3, p->Z, ctx) + || !group->meth->field_mul(group, t4, t3, group->a, ctx) + || !BN_mod_sub_quick(t5, t2, t4, group->field) + || !BN_mod_add_quick(t2, t2, t4, group->field) + || !group->meth->field_sqr(group, t5, t5, ctx) + || !group->meth->field_mul(group, t6, t3, group->b, ctx) + || !group->meth->field_mul(group, t1, p->X, p->Z, ctx) + || !group->meth->field_mul(group, t4, t1, t6, ctx) + || !BN_mod_lshift_quick(t4, t4, 3, group->field) + /* r->X coord output */ + || !BN_mod_sub_quick(r->X, t5, t4, group->field) + || !group->meth->field_mul(group, t1, t1, t2, ctx) + || !group->meth->field_mul(group, t2, t3, t6, ctx) + || !BN_mod_add_quick(t1, t1, t2, group->field) + /* r->Z coord output */ + || !BN_mod_lshift_quick(r->Z, t1, 2, group->field) + || !EC_POINT_copy(s, p)) + return 0; + + r->Z_is_one = 0; + s->Z_is_one = 0; + p->Z_is_one = 0; + + return 1; +} + +/*- + * Differential addition-and-doubling using Eq. (9) and (10) from Izu-Takagi + * "A fast parallel elliptic curve multiplication resistant against side channel + * attacks", as described at + * https://hyperelliptic.org/EFD/g1p/auto-shortw-xz.html#ladder-ladd-2002-it-4 + */ +int ec_GFp_simple_ladder_step(const EC_GROUP *group, + EC_POINT *r, EC_POINT *s, + EC_POINT *p, BN_CTX *ctx) +{ + int ret = 0; + BIGNUM *t0, *t1, *t2, *t3, *t4, *t5, *t6, *t7 = NULL; + + BN_CTX_start(ctx); + t0 = BN_CTX_get(ctx); + t1 = BN_CTX_get(ctx); + t2 = BN_CTX_get(ctx); + t3 = BN_CTX_get(ctx); + t4 = BN_CTX_get(ctx); + t5 = BN_CTX_get(ctx); + t6 = BN_CTX_get(ctx); + t7 = BN_CTX_get(ctx); + + if (t7 == NULL + || !group->meth->field_mul(group, t0, r->X, s->X, ctx) + || !group->meth->field_mul(group, t1, r->Z, s->Z, ctx) + || !group->meth->field_mul(group, t2, r->X, s->Z, ctx) + || !group->meth->field_mul(group, t3, r->Z, s->X, ctx) + || !group->meth->field_mul(group, t4, group->a, t1, ctx) + || !BN_mod_add_quick(t0, t0, t4, group->field) + || !BN_mod_add_quick(t4, t3, t2, group->field) + || !group->meth->field_mul(group, t0, t4, t0, ctx) + || !group->meth->field_sqr(group, t1, t1, ctx) + || !BN_mod_lshift_quick(t7, group->b, 2, group->field) + || !group->meth->field_mul(group, t1, t7, t1, ctx) + || !BN_mod_lshift1_quick(t0, t0, group->field) + || !BN_mod_add_quick(t0, t1, t0, group->field) + || !BN_mod_sub_quick(t1, t2, t3, group->field) + || !group->meth->field_sqr(group, t1, t1, ctx) + || !group->meth->field_mul(group, t3, t1, p->X, ctx) + || !group->meth->field_mul(group, t0, p->Z, t0, ctx) + /* s->X coord output */ + || !BN_mod_sub_quick(s->X, t0, t3, group->field) + /* s->Z coord output */ + || !group->meth->field_mul(group, s->Z, p->Z, t1, ctx) + || !group->meth->field_sqr(group, t3, r->X, ctx) + || !group->meth->field_sqr(group, t2, r->Z, ctx) + || !group->meth->field_mul(group, t4, t2, group->a, ctx) + || !BN_mod_add_quick(t5, r->X, r->Z, group->field) + || !group->meth->field_sqr(group, t5, t5, ctx) + || !BN_mod_sub_quick(t5, t5, t3, group->field) + || !BN_mod_sub_quick(t5, t5, t2, group->field) + || !BN_mod_sub_quick(t6, t3, t4, group->field) + || !group->meth->field_sqr(group, t6, t6, ctx) + || !group->meth->field_mul(group, t0, t2, t5, ctx) + || !group->meth->field_mul(group, t0, t7, t0, ctx) + /* r->X coord output */ + || !BN_mod_sub_quick(r->X, t6, t0, group->field) + || !BN_mod_add_quick(t6, t3, t4, group->field) + || !group->meth->field_sqr(group, t3, t2, ctx) + || !group->meth->field_mul(group, t7, t3, t7, ctx) + || !group->meth->field_mul(group, t5, t5, t6, ctx) + || !BN_mod_lshift1_quick(t5, t5, group->field) + /* r->Z coord output */ + || !BN_mod_add_quick(r->Z, t7, t5, group->field)) + goto err; + + ret = 1; + + err: + BN_CTX_end(ctx); + return ret; +} + +/*- + * Recovers the y-coordinate of r using Eq. (8) from Brier-Joye, "Weierstrass + * Elliptic Curves and Side-Channel Attacks", modified to work in projective + * coordinates and return r in Jacobian projective coordinates. + * + * X4 = two*Y1*X2*Z3*Z2*Z1; + * Y4 = two*b*Z3*SQR(Z2*Z1) + Z3*(a*Z2*Z1+X1*X2)*(X1*Z2+X2*Z1) - X3*SQR(X1*Z2-X2*Z1); + * Z4 = two*Y1*Z3*SQR(Z2)*Z1; + * + * Z4 != 0 because: + * - Z1==0 implies p is at infinity, which would have caused an early exit in + * the caller; + * - Z2==0 implies r is at infinity (handled by the BN_is_zero(r->Z) branch); + * - Z3==0 implies s is at infinity (handled by the BN_is_zero(s->Z) branch); + * - Y1==0 implies p has order 2, so either r or s are infinity and handled by + * one of the BN_is_zero(...) branches. + */ +int ec_GFp_simple_ladder_post(const EC_GROUP *group, + EC_POINT *r, EC_POINT *s, + EC_POINT *p, BN_CTX *ctx) +{ + int ret = 0; + BIGNUM *t0, *t1, *t2, *t3, *t4, *t5, *t6 = NULL; + + if (BN_is_zero(r->Z)) + return EC_POINT_set_to_infinity(group, r); + + if (BN_is_zero(s->Z)) { + /* (X,Y,Z) -> (XZ,YZ**2,Z) */ + if (!group->meth->field_mul(group, r->X, p->X, p->Z, ctx) + || !group->meth->field_sqr(group, r->Z, p->Z, ctx) + || !group->meth->field_mul(group, r->Y, p->Y, r->Z, ctx) + || !BN_copy(r->Z, p->Z) + || !EC_POINT_invert(group, r, ctx)) + return 0; + return 1; + } + + BN_CTX_start(ctx); + t0 = BN_CTX_get(ctx); + t1 = BN_CTX_get(ctx); + t2 = BN_CTX_get(ctx); + t3 = BN_CTX_get(ctx); + t4 = BN_CTX_get(ctx); + t5 = BN_CTX_get(ctx); + t6 = BN_CTX_get(ctx); + + if (t6 == NULL + || !BN_mod_lshift1_quick(t0, p->Y, group->field) + || !group->meth->field_mul(group, t1, r->X, p->Z, ctx) + || !group->meth->field_mul(group, t2, r->Z, s->Z, ctx) + || !group->meth->field_mul(group, t2, t1, t2, ctx) + || !group->meth->field_mul(group, t3, t2, t0, ctx) + || !group->meth->field_mul(group, t2, r->Z, p->Z, ctx) + || !group->meth->field_sqr(group, t4, t2, ctx) + || !BN_mod_lshift1_quick(t5, group->b, group->field) + || !group->meth->field_mul(group, t4, t4, t5, ctx) + || !group->meth->field_mul(group, t6, t2, group->a, ctx) + || !group->meth->field_mul(group, t5, r->X, p->X, ctx) + || !BN_mod_add_quick(t5, t6, t5, group->field) + || !group->meth->field_mul(group, t6, r->Z, p->X, ctx) + || !BN_mod_add_quick(t2, t6, t1, group->field) + || !group->meth->field_mul(group, t5, t5, t2, ctx) + || !BN_mod_sub_quick(t6, t6, t1, group->field) + || !group->meth->field_sqr(group, t6, t6, ctx) + || !group->meth->field_mul(group, t6, t6, s->X, ctx) + || !BN_mod_add_quick(t4, t5, t4, group->field) + || !group->meth->field_mul(group, t4, t4, s->Z, ctx) + || !BN_mod_sub_quick(t4, t4, t6, group->field) + || !group->meth->field_sqr(group, t5, r->Z, ctx) + || !group->meth->field_mul(group, r->Z, p->Z, s->Z, ctx) + || !group->meth->field_mul(group, r->Z, t5, r->Z, ctx) + || !group->meth->field_mul(group, r->Z, r->Z, t0, ctx) + /* t3 := X, t4 := Y */ + /* (X,Y,Z) -> (XZ,YZ**2,Z) */ + || !group->meth->field_mul(group, r->X, t3, r->Z, ctx) + || !group->meth->field_sqr(group, t3, r->Z, ctx) + || !group->meth->field_mul(group, r->Y, t4, t3, ctx)) + goto err; + + ret = 1; + + err: + BN_CTX_end(ctx); + return ret; } |