release/src/router/nettle/ecc-point-mul-g.c

   1 /* ecc-point-mul-g.c */
   2
   3 /* nettle, low-level cryptographics library
   4  *
   5  * Copyright (C) 2013 Niels Möller
   6  *
   7  * The nettle library is free software; you can redistribute it and/or modify
   8  * it under the terms of the GNU Lesser General Public License as published by
   9  * the Free Software Foundation; either version 2.1 of the License, or (at your
  10  * option) any later version.
  11  *
  12  * The nettle library is distributed in the hope that it will be useful, but
  13  * WITHOUT ANY WARRANTY; without even the implied warranty of MERCHANTABILITY
  14  * or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU Lesser General Public
  15  * License for more details.
  16  *
  17  * You should have received a copy of the GNU Lesser General Public License
  18  * along with the nettle library; see the file COPYING.LIB.  If not, write to
  19  * the Free Software Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston,
  20  * MA 02111-1301, USA.
  21  */
  22
  23 /* Development of Nettle's ECC support was funded by the .SE Internet Fund. */
  24
  25 #if HAVE_CONFIG_H
  26 # include "config.h"
  27 #endif
  28
  29 #include <assert.h>
  30
  31 #include "ecc.h"
  32 #include "ecc-internal.h"
  33 #include "nettle-internal.h"
  34
  35 void
  36 ecc_point_mul_g (struct ecc_point *r, const struct ecc_scalar *n)
  37 {
  38   TMP_DECL(scratch, mp_limb_t, 3*ECC_MAX_SIZE + ECC_MUL_G_ITCH (ECC_MAX_SIZE));
  39   mp_limb_t size = r->ecc->size;
  40   mp_size_t itch = 3*size + ECC_MUL_G_ITCH (size);
  41
  42   assert (r->ecc == n->ecc);
  43
  44   TMP_ALLOC (scratch, itch);
  45
  46   ecc_mul_g (r->ecc, scratch, n->p, scratch + 3*size);
  47   ecc_j_to_a (r->ecc, 1, r->p, scratch, scratch + 3*size);
  48 }