diff options
Diffstat (limited to 'deps/openssl/openssl/crypto/ec/ec2_mult.c')
| -rw-r--r-- | deps/openssl/openssl/crypto/ec/ec2_mult.c | 418 |
1 files changed, 0 insertions, 418 deletions
diff --git a/deps/openssl/openssl/crypto/ec/ec2_mult.c b/deps/openssl/openssl/crypto/ec/ec2_mult.c deleted file mode 100644 index e4a1ec5737..0000000000 --- a/deps/openssl/openssl/crypto/ec/ec2_mult.c +++ /dev/null @@ -1,418 +0,0 @@ -/* - * Copyright 2002-2016 The OpenSSL Project Authors. All Rights Reserved. - * - * 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 - */ - -/* ==================================================================== - * Copyright 2002 Sun Microsystems, Inc. ALL RIGHTS RESERVED. - * - * The Elliptic Curve Public-Key Crypto Library (ECC Code) included - * herein is developed by SUN MICROSYSTEMS, INC., and is contributed - * to the OpenSSL project. - * - * The ECC Code is licensed pursuant to the OpenSSL open source - * license provided below. - * - * The software is originally written by Sheueling Chang Shantz and - * Douglas Stebila of Sun Microsystems Laboratories. - * - */ - -#include <openssl/err.h> - -#include "internal/bn_int.h" -#include "ec_lcl.h" - -#ifndef OPENSSL_NO_EC2M - -/*- - * Compute the x-coordinate x/z for the point 2*(x/z) in Montgomery projective - * coordinates. - * Uses algorithm Mdouble in appendix of - * Lopez, J. and Dahab, R. "Fast multiplication on elliptic curves over - * GF(2^m) without precomputation" (CHES '99, LNCS 1717). - * modified to not require precomputation of c=b^{2^{m-1}}. - */ -static int gf2m_Mdouble(const EC_GROUP *group, BIGNUM *x, BIGNUM *z, - BN_CTX *ctx) -{ - BIGNUM *t1; - int ret = 0; - - /* Since Mdouble is static we can guarantee that ctx != NULL. */ - BN_CTX_start(ctx); - t1 = BN_CTX_get(ctx); - if (t1 == NULL) - goto err; - - if (!group->meth->field_sqr(group, x, x, ctx)) - goto err; - if (!group->meth->field_sqr(group, t1, z, ctx)) - goto err; - if (!group->meth->field_mul(group, z, x, t1, ctx)) - goto err; - if (!group->meth->field_sqr(group, x, x, ctx)) - goto err; - if (!group->meth->field_sqr(group, t1, t1, ctx)) - goto err; - if (!group->meth->field_mul(group, t1, group->b, t1, ctx)) - goto err; - if (!BN_GF2m_add(x, x, t1)) - goto err; - - ret = 1; - - err: - BN_CTX_end(ctx); - return ret; -} - -/*- - * Compute the x-coordinate x1/z1 for the point (x1/z1)+(x2/x2) in Montgomery - * projective coordinates. - * Uses algorithm Madd in appendix of - * Lopez, J. and Dahab, R. "Fast multiplication on elliptic curves over - * GF(2^m) without precomputation" (CHES '99, LNCS 1717). - */ -static int gf2m_Madd(const EC_GROUP *group, const BIGNUM *x, BIGNUM *x1, - BIGNUM *z1, const BIGNUM *x2, const BIGNUM *z2, - BN_CTX *ctx) -{ - BIGNUM *t1, *t2; - int ret = 0; - - /* Since Madd is static we can guarantee that ctx != NULL. */ - BN_CTX_start(ctx); - t1 = BN_CTX_get(ctx); - t2 = BN_CTX_get(ctx); - if (t2 == NULL) - goto err; - - if (!BN_copy(t1, x)) - goto err; - if (!group->meth->field_mul(group, x1, x1, z2, ctx)) - goto err; - if (!group->meth->field_mul(group, z1, z1, x2, ctx)) - goto err; - if (!group->meth->field_mul(group, t2, x1, z1, ctx)) - goto err; - if (!BN_GF2m_add(z1, z1, x1)) - goto err; - if (!group->meth->field_sqr(group, z1, z1, ctx)) - goto err; - if (!group->meth->field_mul(group, x1, z1, t1, ctx)) - goto err; - if (!BN_GF2m_add(x1, x1, t2)) - goto err; - - ret = 1; - - err: - BN_CTX_end(ctx); - return ret; -} - -/*- - * Compute the x, y affine coordinates from the point (x1, z1) (x2, z2) - * using Montgomery point multiplication algorithm Mxy() in appendix of - * Lopez, J. and Dahab, R. "Fast multiplication on elliptic curves over - * GF(2^m) without precomputation" (CHES '99, LNCS 1717). - * Returns: - * 0 on error - * 1 if return value should be the point at infinity - * 2 otherwise - */ -static int gf2m_Mxy(const EC_GROUP *group, const BIGNUM *x, const BIGNUM *y, - BIGNUM *x1, BIGNUM *z1, BIGNUM *x2, BIGNUM *z2, - BN_CTX *ctx) -{ - BIGNUM *t3, *t4, *t5; - int ret = 0; - - if (BN_is_zero(z1)) { - BN_zero(x2); - BN_zero(z2); - return 1; - } - - if (BN_is_zero(z2)) { - if (!BN_copy(x2, x)) - return 0; - if (!BN_GF2m_add(z2, x, y)) - return 0; - return 2; - } - - /* Since Mxy is static we can guarantee that ctx != NULL. */ - BN_CTX_start(ctx); - t3 = BN_CTX_get(ctx); - t4 = BN_CTX_get(ctx); - t5 = BN_CTX_get(ctx); - if (t5 == NULL) - goto err; - - if (!BN_one(t5)) - goto err; - - if (!group->meth->field_mul(group, t3, z1, z2, ctx)) - goto err; - - if (!group->meth->field_mul(group, z1, z1, x, ctx)) - goto err; - if (!BN_GF2m_add(z1, z1, x1)) - goto err; - if (!group->meth->field_mul(group, z2, z2, x, ctx)) - goto err; - if (!group->meth->field_mul(group, x1, z2, x1, ctx)) - goto err; - if (!BN_GF2m_add(z2, z2, x2)) - goto err; - - if (!group->meth->field_mul(group, z2, z2, z1, ctx)) - goto err; - if (!group->meth->field_sqr(group, t4, x, ctx)) - goto err; - if (!BN_GF2m_add(t4, t4, y)) - goto err; - if (!group->meth->field_mul(group, t4, t4, t3, ctx)) - goto err; - if (!BN_GF2m_add(t4, t4, z2)) - goto err; - - if (!group->meth->field_mul(group, t3, t3, x, ctx)) - goto err; - if (!group->meth->field_div(group, t3, t5, t3, ctx)) - goto err; - if (!group->meth->field_mul(group, t4, t3, t4, ctx)) - goto err; - if (!group->meth->field_mul(group, x2, x1, t3, ctx)) - goto err; - if (!BN_GF2m_add(z2, x2, x)) - goto err; - - if (!group->meth->field_mul(group, z2, z2, t4, ctx)) - goto err; - if (!BN_GF2m_add(z2, z2, y)) - goto err; - - ret = 2; - - err: - BN_CTX_end(ctx); - return ret; -} - -/*- - * Computes scalar*point and stores the result in r. - * point can not equal r. - * Uses a modified algorithm 2P of - * Lopez, J. and Dahab, R. "Fast multiplication on elliptic curves over - * GF(2^m) without precomputation" (CHES '99, LNCS 1717). - * - * To protect against side-channel attack the function uses constant time swap, - * avoiding conditional branches. - */ -static int ec_GF2m_montgomery_point_multiply(const EC_GROUP *group, - EC_POINT *r, - const BIGNUM *scalar, - const EC_POINT *point, - BN_CTX *ctx) -{ - BIGNUM *x1, *x2, *z1, *z2; - int ret = 0, i, group_top; - BN_ULONG mask, word; - - if (r == point) { - ECerr(EC_F_EC_GF2M_MONTGOMERY_POINT_MULTIPLY, EC_R_INVALID_ARGUMENT); - return 0; - } - - /* if result should be point at infinity */ - if ((scalar == NULL) || BN_is_zero(scalar) || (point == NULL) || - EC_POINT_is_at_infinity(group, point)) { - return EC_POINT_set_to_infinity(group, r); - } - - /* only support affine coordinates */ - if (!point->Z_is_one) - return 0; - - /* - * Since point_multiply is static we can guarantee that ctx != NULL. - */ - BN_CTX_start(ctx); - x1 = BN_CTX_get(ctx); - z1 = BN_CTX_get(ctx); - if (z1 == NULL) - goto err; - - x2 = r->X; - z2 = r->Y; - - group_top = bn_get_top(group->field); - if (bn_wexpand(x1, group_top) == NULL - || bn_wexpand(z1, group_top) == NULL - || bn_wexpand(x2, group_top) == NULL - || bn_wexpand(z2, group_top) == NULL) - goto err; - - if (!BN_GF2m_mod_arr(x1, point->X, group->poly)) - goto err; /* x1 = x */ - if (!BN_one(z1)) - goto err; /* z1 = 1 */ - if (!group->meth->field_sqr(group, z2, x1, ctx)) - goto err; /* z2 = x1^2 = x^2 */ - if (!group->meth->field_sqr(group, x2, z2, ctx)) - goto err; - if (!BN_GF2m_add(x2, x2, group->b)) - goto err; /* x2 = x^4 + b */ - - /* find top most bit and go one past it */ - i = bn_get_top(scalar) - 1; - mask = BN_TBIT; - word = bn_get_words(scalar)[i]; - while (!(word & mask)) - mask >>= 1; - mask >>= 1; - /* if top most bit was at word break, go to next word */ - if (!mask) { - i--; - mask = BN_TBIT; - } - - for (; i >= 0; i--) { - word = bn_get_words(scalar)[i]; - while (mask) { - BN_consttime_swap(word & mask, x1, x2, group_top); - BN_consttime_swap(word & mask, z1, z2, group_top); - if (!gf2m_Madd(group, point->X, x2, z2, x1, z1, ctx)) - goto err; - if (!gf2m_Mdouble(group, x1, z1, ctx)) - goto err; - BN_consttime_swap(word & mask, x1, x2, group_top); - BN_consttime_swap(word & mask, z1, z2, group_top); - mask >>= 1; - } - mask = BN_TBIT; - } - - /* convert out of "projective" coordinates */ - i = gf2m_Mxy(group, point->X, point->Y, x1, z1, x2, z2, ctx); - if (i == 0) - goto err; - else if (i == 1) { - if (!EC_POINT_set_to_infinity(group, r)) - goto err; - } else { - if (!BN_one(r->Z)) - goto err; - r->Z_is_one = 1; - } - - /* GF(2^m) field elements should always have BIGNUM::neg = 0 */ - BN_set_negative(r->X, 0); - BN_set_negative(r->Y, 0); - - ret = 1; - - err: - BN_CTX_end(ctx); - return ret; -} - -/*- - * Computes the sum - * scalar*group->generator + scalars[0]*points[0] + ... + scalars[num-1]*points[num-1] - * gracefully ignoring NULL scalar values. - */ -int ec_GF2m_simple_mul(const EC_GROUP *group, EC_POINT *r, - const BIGNUM *scalar, size_t num, - const EC_POINT *points[], const BIGNUM *scalars[], - BN_CTX *ctx) -{ - BN_CTX *new_ctx = NULL; - int ret = 0; - size_t i; - EC_POINT *p = NULL; - EC_POINT *acc = NULL; - - if (ctx == NULL) { - ctx = new_ctx = BN_CTX_new(); - if (ctx == NULL) - return 0; - } - - /* - * This implementation is more efficient than the wNAF implementation for - * 2 or fewer points. Use the ec_wNAF_mul implementation for 3 or more - * points, or if we can perform a fast multiplication based on - * precomputation. - */ - if ((scalar && (num > 1)) || (num > 2) - || (num == 0 && EC_GROUP_have_precompute_mult(group))) { - ret = ec_wNAF_mul(group, r, scalar, num, points, scalars, ctx); - goto err; - } - - if ((p = EC_POINT_new(group)) == NULL) - goto err; - if ((acc = EC_POINT_new(group)) == NULL) - goto err; - - if (!EC_POINT_set_to_infinity(group, acc)) - goto err; - - if (scalar) { - if (!ec_GF2m_montgomery_point_multiply - (group, p, scalar, group->generator, ctx)) - goto err; - if (BN_is_negative(scalar)) - if (!group->meth->invert(group, p, ctx)) - goto err; - if (!group->meth->add(group, acc, acc, p, ctx)) - goto err; - } - - for (i = 0; i < num; i++) { - if (!ec_GF2m_montgomery_point_multiply - (group, p, scalars[i], points[i], ctx)) - goto err; - if (BN_is_negative(scalars[i])) - if (!group->meth->invert(group, p, ctx)) - goto err; - if (!group->meth->add(group, acc, acc, p, ctx)) - goto err; - } - - if (!EC_POINT_copy(r, acc)) - goto err; - - ret = 1; - - err: - EC_POINT_free(p); - EC_POINT_free(acc); - BN_CTX_free(new_ctx); - return ret; -} - -/* - * Precomputation for point multiplication: fall back to wNAF methods because - * ec_GF2m_simple_mul() uses ec_wNAF_mul() if appropriate - */ - -int ec_GF2m_precompute_mult(EC_GROUP *group, BN_CTX *ctx) -{ - return ec_wNAF_precompute_mult(group, ctx); -} - -int ec_GF2m_have_precompute_mult(const EC_GROUP *group) -{ - return ec_wNAF_have_precompute_mult(group); -} - -#endif |