ecc-gost-gc512a.c

   1 /* ecc-gost-gc512a.c
   2
   3    Copyright (C) 2016-2020 Dmitry Eremin-Solenikov
   4
   5    This file is part of GNU Nettle.
   6
   7    GNU Nettle is free software: you can redistribute it and/or
   8    modify it under the terms of either:
   9
  10      * the GNU Lesser General Public License as published by the Free
  11        Software Foundation; either version 3 of the License, or (at your
  12        option) any later version.
  13
  14    or
  15
  16      * the GNU General Public License as published by the Free
  17        Software Foundation; either version 2 of the License, or (at your
  18        option) any later version.
  19
  20    or both in parallel, as here.
  21
  22    GNU Nettle is distributed in the hope that it will be useful,
  23    but WITHOUT ANY WARRANTY; without even the implied warranty of
  24    MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
  25    General Public License for more details.
  26
  27    You should have received copies of the GNU General Public License and
  28    the GNU Lesser General Public License along with this program.  If
  29    not, see http://www.gnu.org/licenses/.
  30 */
  31
  32 #if HAVE_CONFIG_H
  33 # include "config.h"
  34 #endif
  35
  36 #include <assert.h>
  37
  38 #include "ecc.h"
  39 #include "ecc-internal.h"
  40
  41 #define USE_REDC 0
  42
  43 #include "ecc-gost-gc512a.h"
  44
  45 static void
  46 ecc_gost_gc512a_modp (const struct ecc_modulo *m, mp_limb_t *rp, mp_limb_t *xp)
  47 {
  48   mp_size_t mn = m->size;
  49   mp_limb_t hi;
  50
  51   hi = mpn_addmul_1(xp, xp + mn, mn, 0x239);
  52   hi = sec_add_1 (xp, xp, mn, hi * 0x239);
  53   hi = sec_add_1 (rp, xp, mn, hi * 0x239);
  54   assert(hi == 0);
  55 }
  56
  57 #define ecc_gost_gc512a_modp ecc_gost_gc512a_modp
  58 #define ecc_gost_gc512a_modq ecc_mod
  59
  60 const struct ecc_curve _nettle_gost_gc512a =
  61 {
  62   {
  63     512,
  64     ECC_LIMB_SIZE,
  65     ECC_BMODP_SIZE,
  66     ECC_REDC_SIZE,
  67     ECC_MOD_INV_ITCH (ECC_LIMB_SIZE),
  68     0,
  69     0,
  70
  71     ecc_p,
  72     ecc_Bmodp,
  73     ecc_Bmodp_shifted,
  74     ecc_Bm2p,
  75     ecc_redc_ppm1,
  76
  77     ecc_pp1h,
  78     ecc_gost_gc512a_modp,
  79     ecc_gost_gc512a_modp,
  80     ecc_mod_inv,
  81     NULL,
  82     NULL,
  83   },
  84   {
  85     512,
  86     ECC_LIMB_SIZE,
  87     ECC_BMODQ_SIZE,
  88     0,
  89     ECC_MOD_INV_ITCH (ECC_LIMB_SIZE),
  90     0,
  91     0,
  92
  93     ecc_q,
  94     ecc_Bmodq,
  95     ecc_Bmodq_shifted,
  96     ecc_Bm2q,
  97     NULL,
  98     ecc_qp1h,
  99
 100     ecc_gost_gc512a_modq,
 101     ecc_gost_gc512a_modq,
 102     ecc_mod_inv,
 103     NULL,
 104     NULL,
 105   },
 106
 107   USE_REDC,
 108   ECC_PIPPENGER_K,
 109   ECC_PIPPENGER_C,
 110
 111   ECC_ADD_JJA_ITCH (ECC_LIMB_SIZE),
 112   ECC_ADD_JJJ_ITCH (ECC_LIMB_SIZE),
 113   ECC_DUP_JJ_ITCH (ECC_LIMB_SIZE),
 114   ECC_MUL_A_ITCH (ECC_LIMB_SIZE),
 115   ECC_MUL_G_ITCH (ECC_LIMB_SIZE),
 116   ECC_J_TO_A_ITCH (ECC_LIMB_SIZE, ECC_MOD_INV_ITCH(ECC_LIMB_SIZE)),
 117
 118   ecc_add_jja,
 119   ecc_add_jjj,
 120   ecc_dup_jj,
 121   ecc_mul_a,
 122   ecc_mul_g,
 123   ecc_j_to_a,
 124
 125   ecc_b,
 126   ecc_unit,
 127   ecc_table
 128 };
 129
 130 const struct ecc_curve *nettle_get_gost_gc512a(void)
 131 {
 132   return &_nettle_gost_gc512a;
 133 }