1*f9fbec18Smcpowers /* 2*f9fbec18Smcpowers * ***** BEGIN LICENSE BLOCK ***** 3*f9fbec18Smcpowers * Version: MPL 1.1/GPL 2.0/LGPL 2.1 4*f9fbec18Smcpowers * 5*f9fbec18Smcpowers * The contents of this file are subject to the Mozilla Public License Version 6*f9fbec18Smcpowers * 1.1 (the "License"); you may not use this file except in compliance with 7*f9fbec18Smcpowers * the License. You may obtain a copy of the License at 8*f9fbec18Smcpowers * http://www.mozilla.org/MPL/ 9*f9fbec18Smcpowers * 10*f9fbec18Smcpowers * Software distributed under the License is distributed on an "AS IS" basis, 11*f9fbec18Smcpowers * WITHOUT WARRANTY OF ANY KIND, either express or implied. See the License 12*f9fbec18Smcpowers * for the specific language governing rights and limitations under the 13*f9fbec18Smcpowers * License. 14*f9fbec18Smcpowers * 15*f9fbec18Smcpowers * The Original Code is the elliptic curve math library for prime field curves. 16*f9fbec18Smcpowers * 17*f9fbec18Smcpowers * The Initial Developer of the Original Code is 18*f9fbec18Smcpowers * Sun Microsystems, Inc. 19*f9fbec18Smcpowers * Portions created by the Initial Developer are Copyright (C) 2003 20*f9fbec18Smcpowers * the Initial Developer. All Rights Reserved. 21*f9fbec18Smcpowers * 22*f9fbec18Smcpowers * Contributor(s): 23*f9fbec18Smcpowers * Douglas Stebila <douglas@stebila.ca> 24*f9fbec18Smcpowers * 25*f9fbec18Smcpowers * Alternatively, the contents of this file may be used under the terms of 26*f9fbec18Smcpowers * either the GNU General Public License Version 2 or later (the "GPL"), or 27*f9fbec18Smcpowers * the GNU Lesser General Public License Version 2.1 or later (the "LGPL"), 28*f9fbec18Smcpowers * in which case the provisions of the GPL or the LGPL are applicable instead 29*f9fbec18Smcpowers * of those above. If you wish to allow use of your version of this file only 30*f9fbec18Smcpowers * under the terms of either the GPL or the LGPL, and not to allow others to 31*f9fbec18Smcpowers * use your version of this file under the terms of the MPL, indicate your 32*f9fbec18Smcpowers * decision by deleting the provisions above and replace them with the notice 33*f9fbec18Smcpowers * and other provisions required by the GPL or the LGPL. If you do not delete 34*f9fbec18Smcpowers * the provisions above, a recipient may use your version of this file under 35*f9fbec18Smcpowers * the terms of any one of the MPL, the GPL or the LGPL. 36*f9fbec18Smcpowers * 37*f9fbec18Smcpowers * ***** END LICENSE BLOCK ***** */ 38*f9fbec18Smcpowers /* 39*f9fbec18Smcpowers * Copyright 2007 Sun Microsystems, Inc. All rights reserved. 40*f9fbec18Smcpowers * Use is subject to license terms. 41*f9fbec18Smcpowers * 42*f9fbec18Smcpowers * Sun elects to use this software under the MPL license. 43*f9fbec18Smcpowers */ 44*f9fbec18Smcpowers 45*f9fbec18Smcpowers #pragma ident "%Z%%M% %I% %E% SMI" 46*f9fbec18Smcpowers 47*f9fbec18Smcpowers #include "ecp.h" 48*f9fbec18Smcpowers #include "mpi.h" 49*f9fbec18Smcpowers #include "mplogic.h" 50*f9fbec18Smcpowers #include "mpi-priv.h" 51*f9fbec18Smcpowers #ifndef _KERNEL 52*f9fbec18Smcpowers #include <stdlib.h> 53*f9fbec18Smcpowers #endif 54*f9fbec18Smcpowers 55*f9fbec18Smcpowers /* Fast modular reduction for p384 = 2^384 - 2^128 - 2^96 + 2^32 - 1. a can be r. 56*f9fbec18Smcpowers * Uses algorithm 2.30 from Hankerson, Menezes, Vanstone. Guide to 57*f9fbec18Smcpowers * Elliptic Curve Cryptography. */ 58*f9fbec18Smcpowers mp_err 59*f9fbec18Smcpowers ec_GFp_nistp384_mod(const mp_int *a, mp_int *r, const GFMethod *meth) 60*f9fbec18Smcpowers { 61*f9fbec18Smcpowers mp_err res = MP_OKAY; 62*f9fbec18Smcpowers int a_bits = mpl_significant_bits(a); 63*f9fbec18Smcpowers int i; 64*f9fbec18Smcpowers 65*f9fbec18Smcpowers /* m1, m2 are statically-allocated mp_int of exactly the size we need */ 66*f9fbec18Smcpowers mp_int m[10]; 67*f9fbec18Smcpowers 68*f9fbec18Smcpowers #ifdef ECL_THIRTY_TWO_BIT 69*f9fbec18Smcpowers mp_digit s[10][12]; 70*f9fbec18Smcpowers for (i = 0; i < 10; i++) { 71*f9fbec18Smcpowers MP_SIGN(&m[i]) = MP_ZPOS; 72*f9fbec18Smcpowers MP_ALLOC(&m[i]) = 12; 73*f9fbec18Smcpowers MP_USED(&m[i]) = 12; 74*f9fbec18Smcpowers MP_DIGITS(&m[i]) = s[i]; 75*f9fbec18Smcpowers } 76*f9fbec18Smcpowers #else 77*f9fbec18Smcpowers mp_digit s[10][6]; 78*f9fbec18Smcpowers for (i = 0; i < 10; i++) { 79*f9fbec18Smcpowers MP_SIGN(&m[i]) = MP_ZPOS; 80*f9fbec18Smcpowers MP_ALLOC(&m[i]) = 6; 81*f9fbec18Smcpowers MP_USED(&m[i]) = 6; 82*f9fbec18Smcpowers MP_DIGITS(&m[i]) = s[i]; 83*f9fbec18Smcpowers } 84*f9fbec18Smcpowers #endif 85*f9fbec18Smcpowers 86*f9fbec18Smcpowers #ifdef ECL_THIRTY_TWO_BIT 87*f9fbec18Smcpowers /* for polynomials larger than twice the field size or polynomials 88*f9fbec18Smcpowers * not using all words, use regular reduction */ 89*f9fbec18Smcpowers if ((a_bits > 768) || (a_bits <= 736)) { 90*f9fbec18Smcpowers MP_CHECKOK(mp_mod(a, &meth->irr, r)); 91*f9fbec18Smcpowers } else { 92*f9fbec18Smcpowers for (i = 0; i < 12; i++) { 93*f9fbec18Smcpowers s[0][i] = MP_DIGIT(a, i); 94*f9fbec18Smcpowers } 95*f9fbec18Smcpowers s[1][0] = 0; 96*f9fbec18Smcpowers s[1][1] = 0; 97*f9fbec18Smcpowers s[1][2] = 0; 98*f9fbec18Smcpowers s[1][3] = 0; 99*f9fbec18Smcpowers s[1][4] = MP_DIGIT(a, 21); 100*f9fbec18Smcpowers s[1][5] = MP_DIGIT(a, 22); 101*f9fbec18Smcpowers s[1][6] = MP_DIGIT(a, 23); 102*f9fbec18Smcpowers s[1][7] = 0; 103*f9fbec18Smcpowers s[1][8] = 0; 104*f9fbec18Smcpowers s[1][9] = 0; 105*f9fbec18Smcpowers s[1][10] = 0; 106*f9fbec18Smcpowers s[1][11] = 0; 107*f9fbec18Smcpowers for (i = 0; i < 12; i++) { 108*f9fbec18Smcpowers s[2][i] = MP_DIGIT(a, i+12); 109*f9fbec18Smcpowers } 110*f9fbec18Smcpowers s[3][0] = MP_DIGIT(a, 21); 111*f9fbec18Smcpowers s[3][1] = MP_DIGIT(a, 22); 112*f9fbec18Smcpowers s[3][2] = MP_DIGIT(a, 23); 113*f9fbec18Smcpowers for (i = 3; i < 12; i++) { 114*f9fbec18Smcpowers s[3][i] = MP_DIGIT(a, i+9); 115*f9fbec18Smcpowers } 116*f9fbec18Smcpowers s[4][0] = 0; 117*f9fbec18Smcpowers s[4][1] = MP_DIGIT(a, 23); 118*f9fbec18Smcpowers s[4][2] = 0; 119*f9fbec18Smcpowers s[4][3] = MP_DIGIT(a, 20); 120*f9fbec18Smcpowers for (i = 4; i < 12; i++) { 121*f9fbec18Smcpowers s[4][i] = MP_DIGIT(a, i+8); 122*f9fbec18Smcpowers } 123*f9fbec18Smcpowers s[5][0] = 0; 124*f9fbec18Smcpowers s[5][1] = 0; 125*f9fbec18Smcpowers s[5][2] = 0; 126*f9fbec18Smcpowers s[5][3] = 0; 127*f9fbec18Smcpowers s[5][4] = MP_DIGIT(a, 20); 128*f9fbec18Smcpowers s[5][5] = MP_DIGIT(a, 21); 129*f9fbec18Smcpowers s[5][6] = MP_DIGIT(a, 22); 130*f9fbec18Smcpowers s[5][7] = MP_DIGIT(a, 23); 131*f9fbec18Smcpowers s[5][8] = 0; 132*f9fbec18Smcpowers s[5][9] = 0; 133*f9fbec18Smcpowers s[5][10] = 0; 134*f9fbec18Smcpowers s[5][11] = 0; 135*f9fbec18Smcpowers s[6][0] = MP_DIGIT(a, 20); 136*f9fbec18Smcpowers s[6][1] = 0; 137*f9fbec18Smcpowers s[6][2] = 0; 138*f9fbec18Smcpowers s[6][3] = MP_DIGIT(a, 21); 139*f9fbec18Smcpowers s[6][4] = MP_DIGIT(a, 22); 140*f9fbec18Smcpowers s[6][5] = MP_DIGIT(a, 23); 141*f9fbec18Smcpowers s[6][6] = 0; 142*f9fbec18Smcpowers s[6][7] = 0; 143*f9fbec18Smcpowers s[6][8] = 0; 144*f9fbec18Smcpowers s[6][9] = 0; 145*f9fbec18Smcpowers s[6][10] = 0; 146*f9fbec18Smcpowers s[6][11] = 0; 147*f9fbec18Smcpowers s[7][0] = MP_DIGIT(a, 23); 148*f9fbec18Smcpowers for (i = 1; i < 12; i++) { 149*f9fbec18Smcpowers s[7][i] = MP_DIGIT(a, i+11); 150*f9fbec18Smcpowers } 151*f9fbec18Smcpowers s[8][0] = 0; 152*f9fbec18Smcpowers s[8][1] = MP_DIGIT(a, 20); 153*f9fbec18Smcpowers s[8][2] = MP_DIGIT(a, 21); 154*f9fbec18Smcpowers s[8][3] = MP_DIGIT(a, 22); 155*f9fbec18Smcpowers s[8][4] = MP_DIGIT(a, 23); 156*f9fbec18Smcpowers s[8][5] = 0; 157*f9fbec18Smcpowers s[8][6] = 0; 158*f9fbec18Smcpowers s[8][7] = 0; 159*f9fbec18Smcpowers s[8][8] = 0; 160*f9fbec18Smcpowers s[8][9] = 0; 161*f9fbec18Smcpowers s[8][10] = 0; 162*f9fbec18Smcpowers s[8][11] = 0; 163*f9fbec18Smcpowers s[9][0] = 0; 164*f9fbec18Smcpowers s[9][1] = 0; 165*f9fbec18Smcpowers s[9][2] = 0; 166*f9fbec18Smcpowers s[9][3] = MP_DIGIT(a, 23); 167*f9fbec18Smcpowers s[9][4] = MP_DIGIT(a, 23); 168*f9fbec18Smcpowers s[9][5] = 0; 169*f9fbec18Smcpowers s[9][6] = 0; 170*f9fbec18Smcpowers s[9][7] = 0; 171*f9fbec18Smcpowers s[9][8] = 0; 172*f9fbec18Smcpowers s[9][9] = 0; 173*f9fbec18Smcpowers s[9][10] = 0; 174*f9fbec18Smcpowers s[9][11] = 0; 175*f9fbec18Smcpowers 176*f9fbec18Smcpowers MP_CHECKOK(mp_add(&m[0], &m[1], r)); 177*f9fbec18Smcpowers MP_CHECKOK(mp_add(r, &m[1], r)); 178*f9fbec18Smcpowers MP_CHECKOK(mp_add(r, &m[2], r)); 179*f9fbec18Smcpowers MP_CHECKOK(mp_add(r, &m[3], r)); 180*f9fbec18Smcpowers MP_CHECKOK(mp_add(r, &m[4], r)); 181*f9fbec18Smcpowers MP_CHECKOK(mp_add(r, &m[5], r)); 182*f9fbec18Smcpowers MP_CHECKOK(mp_add(r, &m[6], r)); 183*f9fbec18Smcpowers MP_CHECKOK(mp_sub(r, &m[7], r)); 184*f9fbec18Smcpowers MP_CHECKOK(mp_sub(r, &m[8], r)); 185*f9fbec18Smcpowers MP_CHECKOK(mp_submod(r, &m[9], &meth->irr, r)); 186*f9fbec18Smcpowers s_mp_clamp(r); 187*f9fbec18Smcpowers } 188*f9fbec18Smcpowers #else 189*f9fbec18Smcpowers /* for polynomials larger than twice the field size or polynomials 190*f9fbec18Smcpowers * not using all words, use regular reduction */ 191*f9fbec18Smcpowers if ((a_bits > 768) || (a_bits <= 736)) { 192*f9fbec18Smcpowers MP_CHECKOK(mp_mod(a, &meth->irr, r)); 193*f9fbec18Smcpowers } else { 194*f9fbec18Smcpowers for (i = 0; i < 6; i++) { 195*f9fbec18Smcpowers s[0][i] = MP_DIGIT(a, i); 196*f9fbec18Smcpowers } 197*f9fbec18Smcpowers s[1][0] = 0; 198*f9fbec18Smcpowers s[1][1] = 0; 199*f9fbec18Smcpowers s[1][2] = (MP_DIGIT(a, 10) >> 32) | (MP_DIGIT(a, 11) << 32); 200*f9fbec18Smcpowers s[1][3] = MP_DIGIT(a, 11) >> 32; 201*f9fbec18Smcpowers s[1][4] = 0; 202*f9fbec18Smcpowers s[1][5] = 0; 203*f9fbec18Smcpowers for (i = 0; i < 6; i++) { 204*f9fbec18Smcpowers s[2][i] = MP_DIGIT(a, i+6); 205*f9fbec18Smcpowers } 206*f9fbec18Smcpowers s[3][0] = (MP_DIGIT(a, 10) >> 32) | (MP_DIGIT(a, 11) << 32); 207*f9fbec18Smcpowers s[3][1] = (MP_DIGIT(a, 11) >> 32) | (MP_DIGIT(a, 6) << 32); 208*f9fbec18Smcpowers for (i = 2; i < 6; i++) { 209*f9fbec18Smcpowers s[3][i] = (MP_DIGIT(a, i+4) >> 32) | (MP_DIGIT(a, i+5) << 32); 210*f9fbec18Smcpowers } 211*f9fbec18Smcpowers s[4][0] = (MP_DIGIT(a, 11) >> 32) << 32; 212*f9fbec18Smcpowers s[4][1] = MP_DIGIT(a, 10) << 32; 213*f9fbec18Smcpowers for (i = 2; i < 6; i++) { 214*f9fbec18Smcpowers s[4][i] = MP_DIGIT(a, i+4); 215*f9fbec18Smcpowers } 216*f9fbec18Smcpowers s[5][0] = 0; 217*f9fbec18Smcpowers s[5][1] = 0; 218*f9fbec18Smcpowers s[5][2] = MP_DIGIT(a, 10); 219*f9fbec18Smcpowers s[5][3] = MP_DIGIT(a, 11); 220*f9fbec18Smcpowers s[5][4] = 0; 221*f9fbec18Smcpowers s[5][5] = 0; 222*f9fbec18Smcpowers s[6][0] = (MP_DIGIT(a, 10) << 32) >> 32; 223*f9fbec18Smcpowers s[6][1] = (MP_DIGIT(a, 10) >> 32) << 32; 224*f9fbec18Smcpowers s[6][2] = MP_DIGIT(a, 11); 225*f9fbec18Smcpowers s[6][3] = 0; 226*f9fbec18Smcpowers s[6][4] = 0; 227*f9fbec18Smcpowers s[6][5] = 0; 228*f9fbec18Smcpowers s[7][0] = (MP_DIGIT(a, 11) >> 32) | (MP_DIGIT(a, 6) << 32); 229*f9fbec18Smcpowers for (i = 1; i < 6; i++) { 230*f9fbec18Smcpowers s[7][i] = (MP_DIGIT(a, i+5) >> 32) | (MP_DIGIT(a, i+6) << 32); 231*f9fbec18Smcpowers } 232*f9fbec18Smcpowers s[8][0] = MP_DIGIT(a, 10) << 32; 233*f9fbec18Smcpowers s[8][1] = (MP_DIGIT(a, 10) >> 32) | (MP_DIGIT(a, 11) << 32); 234*f9fbec18Smcpowers s[8][2] = MP_DIGIT(a, 11) >> 32; 235*f9fbec18Smcpowers s[8][3] = 0; 236*f9fbec18Smcpowers s[8][4] = 0; 237*f9fbec18Smcpowers s[8][5] = 0; 238*f9fbec18Smcpowers s[9][0] = 0; 239*f9fbec18Smcpowers s[9][1] = (MP_DIGIT(a, 11) >> 32) << 32; 240*f9fbec18Smcpowers s[9][2] = MP_DIGIT(a, 11) >> 32; 241*f9fbec18Smcpowers s[9][3] = 0; 242*f9fbec18Smcpowers s[9][4] = 0; 243*f9fbec18Smcpowers s[9][5] = 0; 244*f9fbec18Smcpowers 245*f9fbec18Smcpowers MP_CHECKOK(mp_add(&m[0], &m[1], r)); 246*f9fbec18Smcpowers MP_CHECKOK(mp_add(r, &m[1], r)); 247*f9fbec18Smcpowers MP_CHECKOK(mp_add(r, &m[2], r)); 248*f9fbec18Smcpowers MP_CHECKOK(mp_add(r, &m[3], r)); 249*f9fbec18Smcpowers MP_CHECKOK(mp_add(r, &m[4], r)); 250*f9fbec18Smcpowers MP_CHECKOK(mp_add(r, &m[5], r)); 251*f9fbec18Smcpowers MP_CHECKOK(mp_add(r, &m[6], r)); 252*f9fbec18Smcpowers MP_CHECKOK(mp_sub(r, &m[7], r)); 253*f9fbec18Smcpowers MP_CHECKOK(mp_sub(r, &m[8], r)); 254*f9fbec18Smcpowers MP_CHECKOK(mp_submod(r, &m[9], &meth->irr, r)); 255*f9fbec18Smcpowers s_mp_clamp(r); 256*f9fbec18Smcpowers } 257*f9fbec18Smcpowers #endif 258*f9fbec18Smcpowers 259*f9fbec18Smcpowers CLEANUP: 260*f9fbec18Smcpowers return res; 261*f9fbec18Smcpowers } 262*f9fbec18Smcpowers 263*f9fbec18Smcpowers /* Compute the square of polynomial a, reduce modulo p384. Store the 264*f9fbec18Smcpowers * result in r. r could be a. Uses optimized modular reduction for p384. 265*f9fbec18Smcpowers */ 266*f9fbec18Smcpowers mp_err 267*f9fbec18Smcpowers ec_GFp_nistp384_sqr(const mp_int *a, mp_int *r, const GFMethod *meth) 268*f9fbec18Smcpowers { 269*f9fbec18Smcpowers mp_err res = MP_OKAY; 270*f9fbec18Smcpowers 271*f9fbec18Smcpowers MP_CHECKOK(mp_sqr(a, r)); 272*f9fbec18Smcpowers MP_CHECKOK(ec_GFp_nistp384_mod(r, r, meth)); 273*f9fbec18Smcpowers CLEANUP: 274*f9fbec18Smcpowers return res; 275*f9fbec18Smcpowers } 276*f9fbec18Smcpowers 277*f9fbec18Smcpowers /* Compute the product of two polynomials a and b, reduce modulo p384. 278*f9fbec18Smcpowers * Store the result in r. r could be a or b; a could be b. Uses 279*f9fbec18Smcpowers * optimized modular reduction for p384. */ 280*f9fbec18Smcpowers mp_err 281*f9fbec18Smcpowers ec_GFp_nistp384_mul(const mp_int *a, const mp_int *b, mp_int *r, 282*f9fbec18Smcpowers const GFMethod *meth) 283*f9fbec18Smcpowers { 284*f9fbec18Smcpowers mp_err res = MP_OKAY; 285*f9fbec18Smcpowers 286*f9fbec18Smcpowers MP_CHECKOK(mp_mul(a, b, r)); 287*f9fbec18Smcpowers MP_CHECKOK(ec_GFp_nistp384_mod(r, r, meth)); 288*f9fbec18Smcpowers CLEANUP: 289*f9fbec18Smcpowers return res; 290*f9fbec18Smcpowers } 291*f9fbec18Smcpowers 292*f9fbec18Smcpowers /* Wire in fast field arithmetic and precomputation of base point for 293*f9fbec18Smcpowers * named curves. */ 294*f9fbec18Smcpowers mp_err 295*f9fbec18Smcpowers ec_group_set_gfp384(ECGroup *group, ECCurveName name) 296*f9fbec18Smcpowers { 297*f9fbec18Smcpowers if (name == ECCurve_NIST_P384) { 298*f9fbec18Smcpowers group->meth->field_mod = &ec_GFp_nistp384_mod; 299*f9fbec18Smcpowers group->meth->field_mul = &ec_GFp_nistp384_mul; 300*f9fbec18Smcpowers group->meth->field_sqr = &ec_GFp_nistp384_sqr; 301*f9fbec18Smcpowers } 302*f9fbec18Smcpowers return MP_OKAY; 303*f9fbec18Smcpowers } 304