rev 16167 : 8170525: Fix minor issues in awt coding

   1 /*
   2  * Copyright (c) 2007, 2011, Oracle and/or its affiliates. All rights reserved.
   3  * Use is subject to license terms.
   4  *
   5  * This library is free software; you can redistribute it and/or
   6  * modify it under the terms of the GNU Lesser General Public
   7  * License as published by the Free Software Foundation; either
   8  * version 2.1 of the License, or (at your option) any later version.
   9  *
  10  * This library is distributed in the hope that it will be useful,
  11  * but WITHOUT ANY WARRANTY; without even the implied warranty of
  12  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
  13  * Lesser General Public License for more details.
  14  *
  15  * You should have received a copy of the GNU Lesser General Public License
  16  * along with this library; if not, write to the Free Software Foundation,
  17  * Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA.
  18  *
  19  * Please contact Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 USA
  20  * or visit www.oracle.com if you need additional information or have any
  21  * questions.
  22  */
  23 
  24 /* *********************************************************************
  25  *
  26  * The Original Code is the elliptic curve math library.
  27  *
  28  * The Initial Developer of the Original Code is
  29  * Sun Microsystems, Inc.
  30  * Portions created by the Initial Developer are Copyright (C) 2003
  31  * the Initial Developer. All Rights Reserved.
  32  *
  33  * Contributor(s):
  34  *   Douglas Stebila <douglas@stebila.ca>, Sun Microsystems Laboratories
  35  *
  36  *********************************************************************** */
  37 
  38 #include "mpi.h"
  39 #include "mplogic.h"
  40 #include "ecl.h"
  41 #include "ecl-priv.h"
  42 #ifndef _KERNEL
  43 #include <stdlib.h>
  44 #endif
  45 
  46 /* Elliptic curve scalar-point multiplication. Computes R(x, y) = k * P(x,
  47  * y).  If x, y = NULL, then P is assumed to be the generator (base point)
  48  * of the group of points on the elliptic curve. Input and output values
  49  * are assumed to be NOT field-encoded. */
  50 mp_err
  51 ECPoint_mul(const ECGroup *group, const mp_int *k, const mp_int *px,
  52                         const mp_int *py, mp_int *rx, mp_int *ry)
  53 {
  54         mp_err res = MP_OKAY;
  55         mp_int kt;
  56 
  57         ARGCHK((k != NULL) && (group != NULL), MP_BADARG);
  58         MP_DIGITS(&kt) = 0;
  59 
  60         /* want scalar to be less than or equal to group order */
  61         if (mp_cmp(k, &group->order) > 0) {
  62                 MP_CHECKOK(mp_init(&kt, FLAG(k)));
  63                 MP_CHECKOK(mp_mod(k, &group->order, &kt));
  64         } else {
  65                 MP_SIGN(&kt) = MP_ZPOS;
  66                 MP_USED(&kt) = MP_USED(k);
  67                 MP_ALLOC(&kt) = MP_ALLOC(k);
  68                 MP_DIGITS(&kt) = MP_DIGITS(k);
  69         }
  70 
  71         if ((px == NULL) || (py == NULL)) {
  72                 if (group->base_point_mul) {
  73                         MP_CHECKOK(group->base_point_mul(&kt, rx, ry, group));
  74                 } else {
  75                         kt.flag = (mp_sign)0;
  76                         MP_CHECKOK(group->
  77                                            point_mul(&kt, &group->genx, &group->geny, rx, ry,
  78                                                                  group));
  79                 }
  80         } else {
  81                 if (group->meth->field_enc) {
  82                         MP_CHECKOK(group->meth->field_enc(px, rx, group->meth));
  83                         MP_CHECKOK(group->meth->field_enc(py, ry, group->meth));
  84                         MP_CHECKOK(group->point_mul(&kt, rx, ry, rx, ry, group));
  85                 } else {
  86                         kt.flag = (mp_sign)0;
  87                         MP_CHECKOK(group->point_mul(&kt, px, py, rx, ry, group));
  88                 }
  89         }
  90         if (group->meth->field_dec) {
  91                 MP_CHECKOK(group->meth->field_dec(rx, rx, group->meth));
  92                 MP_CHECKOK(group->meth->field_dec(ry, ry, group->meth));
  93         }
  94 
  95   CLEANUP:
  96         if (MP_DIGITS(&kt) != MP_DIGITS(k)) {
  97                 mp_clear(&kt);
  98         }
  99         return res;
 100 }
 101 
 102 /* Elliptic curve scalar-point multiplication. Computes R(x, y) = k1 * G +
 103  * k2 * P(x, y), where G is the generator (base point) of the group of
 104  * points on the elliptic curve. Allows k1 = NULL or { k2, P } = NULL.
 105  * Input and output values are assumed to be NOT field-encoded. */
 106 mp_err
 107 ec_pts_mul_basic(const mp_int *k1, const mp_int *k2, const mp_int *px,
 108                                  const mp_int *py, mp_int *rx, mp_int *ry,
 109                                  const ECGroup *group)
 110 {
 111         mp_err res = MP_OKAY;
 112         mp_int sx, sy;
 113 
 114         ARGCHK(group != NULL, MP_BADARG);
 115         ARGCHK(!((k1 == NULL)
 116                          && ((k2 == NULL) || (px == NULL)
 117                                  || (py == NULL))), MP_BADARG);
 118 
 119         /* if some arguments are not defined used ECPoint_mul */
 120         if (k1 == NULL) {
 121                 return ECPoint_mul(group, k2, px, py, rx, ry);
 122         } else if ((k2 == NULL) || (px == NULL) || (py == NULL)) {
 123                 return ECPoint_mul(group, k1, NULL, NULL, rx, ry);
 124         }
 125 
 126         MP_DIGITS(&sx) = 0;
 127         MP_DIGITS(&sy) = 0;
 128         MP_CHECKOK(mp_init(&sx, FLAG(k1)));
 129         MP_CHECKOK(mp_init(&sy, FLAG(k1)));
 130 
 131         MP_CHECKOK(ECPoint_mul(group, k1, NULL, NULL, &sx, &sy));
 132         MP_CHECKOK(ECPoint_mul(group, k2, px, py, rx, ry));
 133 
 134         if (group->meth->field_enc) {
 135                 MP_CHECKOK(group->meth->field_enc(&sx, &sx, group->meth));
 136                 MP_CHECKOK(group->meth->field_enc(&sy, &sy, group->meth));
 137                 MP_CHECKOK(group->meth->field_enc(rx, rx, group->meth));
 138                 MP_CHECKOK(group->meth->field_enc(ry, ry, group->meth));
 139         }
 140 
 141         MP_CHECKOK(group->point_add(&sx, &sy, rx, ry, rx, ry, group));
 142 
 143         if (group->meth->field_dec) {
 144                 MP_CHECKOK(group->meth->field_dec(rx, rx, group->meth));
 145                 MP_CHECKOK(group->meth->field_dec(ry, ry, group->meth));
 146         }
 147 
 148   CLEANUP:
 149         mp_clear(&sx);
 150         mp_clear(&sy);
 151         return res;
 152 }
 153 
 154 /* Elliptic curve scalar-point multiplication. Computes R(x, y) = k1 * G +
 155  * k2 * P(x, y), where G is the generator (base point) of the group of
 156  * points on the elliptic curve. Allows k1 = NULL or { k2, P } = NULL.
 157  * Input and output values are assumed to be NOT field-encoded. Uses
 158  * algorithm 15 (simultaneous multiple point multiplication) from Brown,
 159  * Hankerson, Lopez, Menezes. Software Implementation of the NIST
 160  * Elliptic Curves over Prime Fields. */
 161 mp_err
 162 ec_pts_mul_simul_w2(const mp_int *k1, const mp_int *k2, const mp_int *px,
 163                                         const mp_int *py, mp_int *rx, mp_int *ry,
 164                                         const ECGroup *group)
 165 {
 166         mp_err res = MP_OKAY;
 167         mp_int precomp[4][4][2];
 168         const mp_int *a, *b;
 169         int i, j;
 170         int ai, bi, d;
 171 
 172         ARGCHK(group != NULL, MP_BADARG);
 173         ARGCHK(!((k1 == NULL)
 174                          && ((k2 == NULL) || (px == NULL)
 175                                  || (py == NULL))), MP_BADARG);
 176 
 177         /* if some arguments are not defined used ECPoint_mul */
 178         if (k1 == NULL) {
 179                 return ECPoint_mul(group, k2, px, py, rx, ry);
 180         } else if ((k2 == NULL) || (px == NULL) || (py == NULL)) {
 181                 return ECPoint_mul(group, k1, NULL, NULL, rx, ry);
 182         }
 183 
 184         /* initialize precomputation table */
 185         for (i = 0; i < 4; i++) {
 186                 for (j = 0; j < 4; j++) {
 187                         MP_DIGITS(&precomp[i][j][0]) = 0;
 188                         MP_DIGITS(&precomp[i][j][1]) = 0;
 189                 }
 190         }
 191         for (i = 0; i < 4; i++) {
 192                 for (j = 0; j < 4; j++) {
 193                          MP_CHECKOK( mp_init_size(&precomp[i][j][0],
 194                                          ECL_MAX_FIELD_SIZE_DIGITS, FLAG(k1)) );
 195                          MP_CHECKOK( mp_init_size(&precomp[i][j][1],
 196                                          ECL_MAX_FIELD_SIZE_DIGITS, FLAG(k1)) );
 197                 }
 198         }
 199 
 200         /* fill precomputation table */
 201         /* assign {k1, k2} = {a, b} such that len(a) >= len(b) */
 202         if (mpl_significant_bits(k1) < mpl_significant_bits(k2)) {
 203                 a = k2;
 204                 b = k1;
 205                 if (group->meth->field_enc) {
 206                         MP_CHECKOK(group->meth->
 207                                            field_enc(px, &precomp[1][0][0], group->meth));
 208                         MP_CHECKOK(group->meth->
 209                                            field_enc(py, &precomp[1][0][1], group->meth));
 210                 } else {
 211                         MP_CHECKOK(mp_copy(px, &precomp[1][0][0]));
 212                         MP_CHECKOK(mp_copy(py, &precomp[1][0][1]));
 213                 }
 214                 MP_CHECKOK(mp_copy(&group->genx, &precomp[0][1][0]));
 215                 MP_CHECKOK(mp_copy(&group->geny, &precomp[0][1][1]));
 216         } else {
 217                 a = k1;
 218                 b = k2;
 219                 MP_CHECKOK(mp_copy(&group->genx, &precomp[1][0][0]));
 220                 MP_CHECKOK(mp_copy(&group->geny, &precomp[1][0][1]));
 221                 if (group->meth->field_enc) {
 222                         MP_CHECKOK(group->meth->
 223                                            field_enc(px, &precomp[0][1][0], group->meth));
 224                         MP_CHECKOK(group->meth->
 225                                            field_enc(py, &precomp[0][1][1], group->meth));
 226                 } else {
 227                         MP_CHECKOK(mp_copy(px, &precomp[0][1][0]));
 228                         MP_CHECKOK(mp_copy(py, &precomp[0][1][1]));
 229                 }
 230         }
 231         /* precompute [*][0][*] */
 232         mp_zero(&precomp[0][0][0]);
 233         mp_zero(&precomp[0][0][1]);
 234         MP_CHECKOK(group->
 235                            point_dbl(&precomp[1][0][0], &precomp[1][0][1],
 236                                                  &precomp[2][0][0], &precomp[2][0][1], group));
 237         MP_CHECKOK(group->
 238                            point_add(&precomp[1][0][0], &precomp[1][0][1],
 239                                                  &precomp[2][0][0], &precomp[2][0][1],
 240                                                  &precomp[3][0][0], &precomp[3][0][1], group));
 241         /* precompute [*][1][*] */
 242         for (i = 1; i < 4; i++) {
 243                 MP_CHECKOK(group->
 244                                    point_add(&precomp[0][1][0], &precomp[0][1][1],
 245                                                          &precomp[i][0][0], &precomp[i][0][1],
 246                                                          &precomp[i][1][0], &precomp[i][1][1], group));
 247         }
 248         /* precompute [*][2][*] */
 249         MP_CHECKOK(group->
 250                            point_dbl(&precomp[0][1][0], &precomp[0][1][1],
 251                                                  &precomp[0][2][0], &precomp[0][2][1], group));
 252         for (i = 1; i < 4; i++) {
 253                 MP_CHECKOK(group->
 254                                    point_add(&precomp[0][2][0], &precomp[0][2][1],
 255                                                          &precomp[i][0][0], &precomp[i][0][1],
 256                                                          &precomp[i][2][0], &precomp[i][2][1], group));
 257         }
 258         /* precompute [*][3][*] */
 259         MP_CHECKOK(group->
 260                            point_add(&precomp[0][1][0], &precomp[0][1][1],
 261                                                  &precomp[0][2][0], &precomp[0][2][1],
 262                                                  &precomp[0][3][0], &precomp[0][3][1], group));
 263         for (i = 1; i < 4; i++) {
 264                 MP_CHECKOK(group->
 265                                    point_add(&precomp[0][3][0], &precomp[0][3][1],
 266                                                          &precomp[i][0][0], &precomp[i][0][1],
 267                                                          &precomp[i][3][0], &precomp[i][3][1], group));
 268         }
 269 
 270         d = (mpl_significant_bits(a) + 1) / 2;
 271 
 272         /* R = inf */
 273         mp_zero(rx);
 274         mp_zero(ry);
 275 
 276         for (i = d - 1; i >= 0; i--) {
 277                 ai = MP_GET_BIT(a, 2 * i + 1);
 278                 ai <<= 1;
 279                 ai |= MP_GET_BIT(a, 2 * i);
 280                 bi = MP_GET_BIT(b, 2 * i + 1);
 281                 bi <<= 1;
 282                 bi |= MP_GET_BIT(b, 2 * i);
 283                 /* R = 2^2 * R */
 284                 MP_CHECKOK(group->point_dbl(rx, ry, rx, ry, group));
 285                 MP_CHECKOK(group->point_dbl(rx, ry, rx, ry, group));
 286                 /* R = R + (ai * A + bi * B) */
 287                 MP_CHECKOK(group->
 288                                    point_add(rx, ry, &precomp[ai][bi][0],
 289                                                          &precomp[ai][bi][1], rx, ry, group));
 290         }
 291 
 292         if (group->meth->field_dec) {
 293                 MP_CHECKOK(group->meth->field_dec(rx, rx, group->meth));
 294                 MP_CHECKOK(group->meth->field_dec(ry, ry, group->meth));
 295         }
 296 
 297   CLEANUP:
 298         for (i = 0; i < 4; i++) {
 299                 for (j = 0; j < 4; j++) {
 300                         mp_clear(&precomp[i][j][0]);
 301                         mp_clear(&precomp[i][j][1]);
 302                 }
 303         }
 304         return res;
 305 }
 306 
 307 /* Elliptic curve scalar-point multiplication. Computes R(x, y) = k1 * G +
 308  * k2 * P(x, y), where G is the generator (base point) of the group of
 309  * points on the elliptic curve. Allows k1 = NULL or { k2, P } = NULL.
 310  * Input and output values are assumed to be NOT field-encoded. */
 311 mp_err
 312 ECPoints_mul(const ECGroup *group, const mp_int *k1, const mp_int *k2,
 313                          const mp_int *px, const mp_int *py, mp_int *rx, mp_int *ry)
 314 {
 315         mp_err res = MP_OKAY;
 316         mp_int k1t, k2t;
 317         const mp_int *k1p, *k2p;
 318 
 319         MP_DIGITS(&k1t) = 0;
 320         MP_DIGITS(&k2t) = 0;
 321 
 322         ARGCHK(group != NULL, MP_BADARG);
 323 
 324         /* want scalar to be less than or equal to group order */
 325         if (k1 != NULL) {
 326                 if (mp_cmp(k1, &group->order) >= 0) {
 327                         MP_CHECKOK(mp_init(&k1t, FLAG(k1)));
 328                         MP_CHECKOK(mp_mod(k1, &group->order, &k1t));
 329                         k1p = &k1t;
 330                 } else {
 331                         k1p = k1;
 332                 }
 333         } else {
 334                 k1p = k1;
 335         }
 336         if (k2 != NULL) {
 337                 if (mp_cmp(k2, &group->order) >= 0) {
 338                         MP_CHECKOK(mp_init(&k2t, FLAG(k2)));
 339                         MP_CHECKOK(mp_mod(k2, &group->order, &k2t));
 340                         k2p = &k2t;
 341                 } else {
 342                         k2p = k2;
 343                 }
 344         } else {
 345                 k2p = k2;
 346         }
 347 
 348         /* if points_mul is defined, then use it */
 349         if (group->points_mul) {
 350                 res = group->points_mul(k1p, k2p, px, py, rx, ry, group);
 351         } else {
 352                 res = ec_pts_mul_simul_w2(k1p, k2p, px, py, rx, ry, group);
 353         }
 354 
 355   CLEANUP:
 356         mp_clear(&k1t);
 357         mp_clear(&k2t);
 358         return res;
 359 }
--- EOF ---