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This adds all exported symbols in the map files explicitly under the following rules: - Symbols mentioned in internal headers go in a section which is valid only for testing, and linking with these symbols will break in library updates. - Symbols mentioned in installed headers go in the exported sections and are considered part of the ABI. - All internal symbols move to internal headers. - The _nettle_md5_compress and _nettle_sha1_compress become exported without the _nettle prefix, due to existing usage.
This adds all exported symbols in the map files explicitly under the following rules: - Symbols mentioned in internal headers go in a section which is valid only for testing, and linking with these symbols will break in library updates. - Symbols mentioned in installed headers go in the exported sections and are considered part of the ABI. - All internal symbols move to internal headers. - The _nettle_md5_compress and _nettle_sha1_compress become exported without the _nettle prefix, due to existing usage.
ecc-dup-jj.c 3.23 KiB
/* ecc-dup-jj.c
Copyright (C) 2013 Niels Möller
This file is part of GNU Nettle.
GNU Nettle is free software: you can redistribute it and/or
modify it under the terms of either:
* the GNU Lesser General Public License as published by the Free
Software Foundation; either version 3 of the License, or (at your
option) any later version.
or
* the GNU General Public License as published by the Free
Software Foundation; either version 2 of the License, or (at your
option) any later version.
or both in parallel, as here.
GNU Nettle is distributed in the hope that it will be useful,
but WITHOUT ANY WARRANTY; without even the implied warranty of
MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
General Public License for more details.
You should have received copies of the GNU General Public License and
the GNU Lesser General Public License along with this program. If
not, see http://www.gnu.org/licenses/.
*/
/* Development of Nettle's ECC support was funded by the .SE Internet Fund. */
#if HAVE_CONFIG_H
# include "config.h"
#endif
#include "ecc.h"
#include "ecc-internal.h"
/* NOTE: Behaviour for corner cases:
+ p = 0 ==> r = 0, correct!
*/
void
ecc_dup_jj (const struct ecc_curve *ecc,
mp_limb_t *r, const mp_limb_t *p,
mp_limb_t *scratch)
{
/* Formulas (from djb,
http://www.hyperelliptic.org/EFD/g1p/auto-shortw-jacobian-3.html#doubling-dbl-2001-b):
Computation Operation Live variables
delta = z^2 sqr delta
gamma = y^2 sqr delta, gamma
z' = (y+z)^2-gamma-delta sqr delta, gamma
alpha = 3*(x-delta)*(x+delta) mul gamma, beta, alpha
beta = x*gamma mul gamma, beta, alpha
x' = alpha^2-8*beta sqr gamma, beta, alpha
y' = alpha*(4*beta-x')-8*gamma^2 mul, sqr
*/
#define delta scratch
#define gamma (scratch + ecc->p.size)
#define beta (scratch + 2*ecc->p.size)
#define g2 (scratch + 3*ecc->p.size)
#define sum (scratch + 4*ecc->p.size)
#define alpha scratch /* Overlap delta */
#define xp p#define yp (p + ecc->p.size)
#define zp (p + 2*ecc->p.size)
/* delta */
ecc_modp_sqr (ecc, delta, zp);
/* gamma */
ecc_modp_sqr (ecc, gamma, yp);
/* z'. Can use beta area as scratch. */
ecc_modp_add (ecc, r + 2*ecc->p.size, yp, zp);
ecc_modp_sqr (ecc, beta, r + 2*ecc->p.size);
ecc_modp_sub (ecc, beta, beta, gamma);
ecc_modp_sub (ecc, r + 2*ecc->p.size, beta, delta);
/* alpha. Can use beta area as scratch, and overwrite delta. */
ecc_modp_add (ecc, sum, xp, delta);
ecc_modp_sub (ecc, delta, xp, delta);
ecc_modp_mul (ecc, beta, sum, delta);
ecc_modp_mul_1 (ecc, alpha, beta, 3);
/* beta */
ecc_modp_mul (ecc, beta, xp, gamma);
/* Do gamma^2 and 4*beta early, to get them out of the way. We can
then use the old area at gamma as scratch. */
ecc_modp_sqr (ecc, g2, gamma);
ecc_modp_mul_1 (ecc, sum, beta, 4);
/* x' */
ecc_modp_sqr (ecc, gamma, alpha); /* Overwrites gamma and beta */
ecc_modp_submul_1 (ecc, gamma, sum, 2);
mpn_copyi (r, gamma, ecc->p.size);
/* y' */
ecc_modp_sub (ecc, sum, sum, r);
ecc_modp_mul (ecc, gamma, sum, alpha);
ecc_modp_submul_1 (ecc, gamma, g2, 8);
mpn_copyi (r + ecc->p.size, gamma, ecc->p.size);
}