usr/src/common/crypto/ecc/ec2_193.c

   1 /*
   2  * ***** BEGIN LICENSE BLOCK *****
   3  * Version: MPL 1.1/GPL 2.0/LGPL 2.1
   4  *
   5  * The contents of this file are subject to the Mozilla Public License Version
   6  * 1.1 (the "License"); you may not use this file except in compliance with
   7  * the License. You may obtain a copy of the License at
   8  * http://www.mozilla.org/MPL/
   9  *
  10  * Software distributed under the License is distributed on an "AS IS" basis,
  11  * WITHOUT WARRANTY OF ANY KIND, either express or implied. See the License
  12  * for the specific language governing rights and limitations under the
  13  * License.
  14  *
  15  * The Original Code is the elliptic curve math library for binary polynomial field curves.
  16  *
  17  * The Initial Developer of the Original Code is
  18  * Sun Microsystems, Inc.
  19  * Portions created by the Initial Developer are Copyright (C) 2003
  20  * the Initial Developer. All Rights Reserved.
  21  *
  22  * Contributor(s):
  23  *   Sheueling Chang-Shantz <sheueling.chang@sun.com>,
  24  *   Stephen Fung <fungstep@hotmail.com>, and
  25  *   Douglas Stebila <douglas@stebila.ca>, Sun Microsystems Laboratories.
  26  *
  27  * Alternatively, the contents of this file may be used under the terms of
  28  * either the GNU General Public License Version 2 or later (the "GPL"), or
  29  * the GNU Lesser General Public License Version 2.1 or later (the "LGPL"),
  30  * in which case the provisions of the GPL or the LGPL are applicable instead
  31  * of those above. If you wish to allow use of your version of this file only
  32  * under the terms of either the GPL or the LGPL, and not to allow others to
  33  * use your version of this file under the terms of the MPL, indicate your
  34  * decision by deleting the provisions above and replace them with the notice
  35  * and other provisions required by the GPL or the LGPL. If you do not delete
  36  * the provisions above, a recipient may use your version of this file under
  37  * the terms of any one of the MPL, the GPL or the LGPL.
  38  *
  39  * ***** END LICENSE BLOCK ***** */
  40 /*
  41  * Copyright 2007 Sun Microsystems, Inc.  All rights reserved.
  42  * Use is subject to license terms.
  43  *
  44  * Sun elects to use this software under the MPL license.
  45  */
  46
  47 #pragma ident   "%Z%%M% %I%     %E% SMI"
  48
  49 #include "ec2.h"
  50 #include "mp_gf2m.h"
  51 #include "mp_gf2m-priv.h"
  52 #include "mpi.h"
  53 #include "mpi-priv.h"
  54 #ifndef _KERNEL
  55 #include <stdlib.h>
  56 #endif
  57
  58 /* Fast reduction for polynomials over a 193-bit curve. Assumes reduction
  59  * polynomial with terms {193, 15, 0}. */
  60 mp_err
  61 ec_GF2m_193_mod(const mp_int *a, mp_int *r, const GFMethod *meth)
  62 {
  63         mp_err res = MP_OKAY;
  64         mp_digit *u, z;
  65
  66         if (a != r) {
  67                 MP_CHECKOK(mp_copy(a, r));
  68         }
  69 #ifdef ECL_SIXTY_FOUR_BIT
  70         if (MP_USED(r) < 7) {
  71                 MP_CHECKOK(s_mp_pad(r, 7));
  72         }
  73         u = MP_DIGITS(r);
  74         MP_USED(r) = 7;
  75
  76         /* u[6] only has 2 significant bits */
  77         z = u[6];
  78         u[3] ^= (z << 14) ^ (z >> 1);
  79         u[2] ^= (z << 63);
  80         z = u[5];
  81         u[3] ^= (z >> 50);
  82         u[2] ^= (z << 14) ^ (z >> 1);
  83         u[1] ^= (z << 63);
  84         z = u[4];
  85         u[2] ^= (z >> 50);
  86         u[1] ^= (z << 14) ^ (z >> 1);
  87         u[0] ^= (z << 63);
  88         z = u[3] >> 1;                          /* z only has 63 significant bits */
  89         u[1] ^= (z >> 49);
  90         u[0] ^= (z << 15) ^ z;
  91         /* clear bits above 193 */
  92         u[6] = u[5] = u[4] = 0;
  93         u[3] ^= z << 1;
  94 #else
  95         if (MP_USED(r) < 13) {
  96                 MP_CHECKOK(s_mp_pad(r, 13));
  97         }
  98         u = MP_DIGITS(r);
  99         MP_USED(r) = 13;
 100
 101         /* u[12] only has 2 significant bits */
 102         z = u[12];
 103         u[6] ^= (z << 14) ^ (z >> 1);
 104         u[5] ^= (z << 31);
 105         z = u[11];
 106         u[6] ^= (z >> 18);
 107         u[5] ^= (z << 14) ^ (z >> 1);
 108         u[4] ^= (z << 31);
 109         z = u[10];
 110         u[5] ^= (z >> 18);
 111         u[4] ^= (z << 14) ^ (z >> 1);
 112         u[3] ^= (z << 31);
 113         z = u[9];
 114         u[4] ^= (z >> 18);
 115         u[3] ^= (z << 14) ^ (z >> 1);
 116         u[2] ^= (z << 31);
 117         z = u[8];
 118         u[3] ^= (z >> 18);
 119         u[2] ^= (z << 14) ^ (z >> 1);
 120         u[1] ^= (z << 31);
 121         z = u[7];
 122         u[2] ^= (z >> 18);
 123         u[1] ^= (z << 14) ^ (z >> 1);
 124         u[0] ^= (z << 31);
 125         z = u[6] >> 1;                          /* z only has 31 significant bits */
 126         u[1] ^= (z >> 17);
 127         u[0] ^= (z << 15) ^ z;
 128         /* clear bits above 193 */
 129         u[12] = u[11] = u[10] = u[9] = u[8] = u[7] = 0;
 130         u[6] ^= z << 1;
 131 #endif
 132         s_mp_clamp(r);
 133
 134   CLEANUP:
 135         return res;
 136 }
 137
 138 /* Fast squaring for polynomials over a 193-bit curve. Assumes reduction
 139  * polynomial with terms {193, 15, 0}. */
 140 mp_err
 141 ec_GF2m_193_sqr(const mp_int *a, mp_int *r, const GFMethod *meth)
 142 {
 143         mp_err res = MP_OKAY;
 144         mp_digit *u, *v;
 145
 146         v = MP_DIGITS(a);
 147
 148 #ifdef ECL_SIXTY_FOUR_BIT
 149         if (MP_USED(a) < 4) {
 150                 return mp_bsqrmod(a, meth->irr_arr, r);
 151         }
 152         if (MP_USED(r) < 7) {
 153                 MP_CHECKOK(s_mp_pad(r, 7));
 154         }
 155         MP_USED(r) = 7;
 156 #else
 157         if (MP_USED(a) < 7) {
 158                 return mp_bsqrmod(a, meth->irr_arr, r);
 159         }
 160         if (MP_USED(r) < 13) {
 161                 MP_CHECKOK(s_mp_pad(r, 13));
 162         }
 163         MP_USED(r) = 13;
 164 #endif
 165         u = MP_DIGITS(r);
 166
 167 #ifdef ECL_THIRTY_TWO_BIT
 168         u[12] = gf2m_SQR0(v[6]);
 169         u[11] = gf2m_SQR1(v[5]);
 170         u[10] = gf2m_SQR0(v[5]);
 171         u[9] = gf2m_SQR1(v[4]);
 172         u[8] = gf2m_SQR0(v[4]);
 173         u[7] = gf2m_SQR1(v[3]);
 174 #endif
 175         u[6] = gf2m_SQR0(v[3]);
 176         u[5] = gf2m_SQR1(v[2]);
 177         u[4] = gf2m_SQR0(v[2]);
 178         u[3] = gf2m_SQR1(v[1]);
 179         u[2] = gf2m_SQR0(v[1]);
 180         u[1] = gf2m_SQR1(v[0]);
 181         u[0] = gf2m_SQR0(v[0]);
 182         return ec_GF2m_193_mod(r, r, meth);
 183
 184   CLEANUP:
 185         return res;
 186 }
 187
 188 /* Fast multiplication for polynomials over a 193-bit curve. Assumes
 189  * reduction polynomial with terms {193, 15, 0}. */
 190 mp_err
 191 ec_GF2m_193_mul(const mp_int *a, const mp_int *b, mp_int *r,
 192                                 const GFMethod *meth)
 193 {
 194         mp_err res = MP_OKAY;
 195         mp_digit a3 = 0, a2 = 0, a1 = 0, a0, b3 = 0, b2 = 0, b1 = 0, b0;
 196
 197 #ifdef ECL_THIRTY_TWO_BIT
 198         mp_digit a6 = 0, a5 = 0, a4 = 0, b6 = 0, b5 = 0, b4 = 0;
 199         mp_digit rm[8];
 200 #endif
 201
 202         if (a == b) {
 203                 return ec_GF2m_193_sqr(a, r, meth);
 204         } else {
 205                 switch (MP_USED(a)) {
 206 #ifdef ECL_THIRTY_TWO_BIT
 207                 case 7:
 208                         a6 = MP_DIGIT(a, 6);
 209                 case 6:
 210                         a5 = MP_DIGIT(a, 5);
 211                 case 5:
 212                         a4 = MP_DIGIT(a, 4);
 213 #endif
 214                 case 4:
 215                         a3 = MP_DIGIT(a, 3);
 216                 case 3:
 217                         a2 = MP_DIGIT(a, 2);
 218                 case 2:
 219                         a1 = MP_DIGIT(a, 1);
 220                 default:
 221                         a0 = MP_DIGIT(a, 0);
 222                 }
 223                 switch (MP_USED(b)) {
 224 #ifdef ECL_THIRTY_TWO_BIT
 225                 case 7:
 226                         b6 = MP_DIGIT(b, 6);
 227                 case 6:
 228                         b5 = MP_DIGIT(b, 5);
 229                 case 5:
 230                         b4 = MP_DIGIT(b, 4);
 231 #endif
 232                 case 4:
 233                         b3 = MP_DIGIT(b, 3);
 234                 case 3:
 235                         b2 = MP_DIGIT(b, 2);
 236                 case 2:
 237                         b1 = MP_DIGIT(b, 1);
 238                 default:
 239                         b0 = MP_DIGIT(b, 0);
 240                 }
 241 #ifdef ECL_SIXTY_FOUR_BIT
 242                 MP_CHECKOK(s_mp_pad(r, 8));
 243                 s_bmul_4x4(MP_DIGITS(r), a3, a2, a1, a0, b3, b2, b1, b0);
 244                 MP_USED(r) = 8;
 245                 s_mp_clamp(r);
 246 #else
 247                 MP_CHECKOK(s_mp_pad(r, 14));
 248                 s_bmul_3x3(MP_DIGITS(r) + 8, a6, a5, a4, b6, b5, b4);
 249                 s_bmul_4x4(MP_DIGITS(r), a3, a2, a1, a0, b3, b2, b1, b0);
 250                 s_bmul_4x4(rm, a3, a6 ^ a2, a5 ^ a1, a4 ^ a0, b3, b6 ^ b2, b5 ^ b1,
 251                                    b4 ^ b0);
 252                 rm[7] ^= MP_DIGIT(r, 7);
 253                 rm[6] ^= MP_DIGIT(r, 6);
 254                 rm[5] ^= MP_DIGIT(r, 5) ^ MP_DIGIT(r, 13);
 255                 rm[4] ^= MP_DIGIT(r, 4) ^ MP_DIGIT(r, 12);
 256                 rm[3] ^= MP_DIGIT(r, 3) ^ MP_DIGIT(r, 11);
 257                 rm[2] ^= MP_DIGIT(r, 2) ^ MP_DIGIT(r, 10);
 258                 rm[1] ^= MP_DIGIT(r, 1) ^ MP_DIGIT(r, 9);
 259                 rm[0] ^= MP_DIGIT(r, 0) ^ MP_DIGIT(r, 8);
 260                 MP_DIGIT(r, 11) ^= rm[7];
 261                 MP_DIGIT(r, 10) ^= rm[6];
 262                 MP_DIGIT(r, 9) ^= rm[5];
 263                 MP_DIGIT(r, 8) ^= rm[4];
 264                 MP_DIGIT(r, 7) ^= rm[3];
 265                 MP_DIGIT(r, 6) ^= rm[2];
 266                 MP_DIGIT(r, 5) ^= rm[1];
 267                 MP_DIGIT(r, 4) ^= rm[0];
 268                 MP_USED(r) = 14;
 269                 s_mp_clamp(r);
 270 #endif
 271                 return ec_GF2m_193_mod(r, r, meth);
 272         }
 273
 274   CLEANUP:
 275         return res;
 276 }
 277
 278 /* Wire in fast field arithmetic for 193-bit curves. */
 279 mp_err
 280 ec_group_set_gf2m193(ECGroup *group, ECCurveName name)
 281 {
 282         group->meth->field_mod = &ec_GF2m_193_mod;
 283         group->meth->field_mul = &ec_GF2m_193_mul;
 284         group->meth->field_sqr = &ec_GF2m_193_sqr;
 285         return MP_OKAY;
 286 }