| 1 | /* -*-c-*- |
| 2 | * |
| 3 | * $Id: gfx.h,v 1.2 2004/03/21 22:52:06 mdw Exp $ |
| 4 | * |
| 5 | * Low-level arithmetic on binary polynomials |
| 6 | * |
| 7 | * (c) 2000 Straylight/Edgeware |
| 8 | */ |
| 9 | |
| 10 | /*----- Licensing notice --------------------------------------------------* |
| 11 | * |
| 12 | * This file is part of Catacomb. |
| 13 | * |
| 14 | * Catacomb is free software; you can redistribute it and/or modify |
| 15 | * it under the terms of the GNU Library General Public License as |
| 16 | * published by the Free Software Foundation; either version 2 of the |
| 17 | * License, or (at your option) any later version. |
| 18 | * |
| 19 | * Catacomb is distributed in the hope that it will be useful, |
| 20 | * but WITHOUT ANY WARRANTY; without even the implied warranty of |
| 21 | * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the |
| 22 | * GNU Library General Public License for more details. |
| 23 | * |
| 24 | * You should have received a copy of the GNU Library General Public |
| 25 | * License along with Catacomb; if not, write to the Free |
| 26 | * Software Foundation, Inc., 59 Temple Place - Suite 330, Boston, |
| 27 | * MA 02111-1307, USA. |
| 28 | */ |
| 29 | |
| 30 | /*----- Revision history --------------------------------------------------* |
| 31 | * |
| 32 | * $Log: gfx.h,v $ |
| 33 | * Revision 1.2 2004/03/21 22:52:06 mdw |
| 34 | * Merge and close elliptic curve branch. |
| 35 | * |
| 36 | * Revision 1.1.4.1 2004/03/21 22:39:46 mdw |
| 37 | * Elliptic curves on binary fields work. |
| 38 | * |
| 39 | * Revision 1.1 2000/10/08 15:49:37 mdw |
| 40 | * First glimmerings of binary polynomial arithmetic. |
| 41 | * |
| 42 | */ |
| 43 | |
| 44 | #ifndef CATACOMB_GFX_H |
| 45 | #define CATACOMB_GFX_H |
| 46 | |
| 47 | #ifdef __cplusplus |
| 48 | extern "C" { |
| 49 | #endif |
| 50 | |
| 51 | /*----- Header files ------------------------------------------------------*/ |
| 52 | |
| 53 | #ifndef CATACOMB_MPX_H |
| 54 | # include "mpx.h" |
| 55 | #endif |
| 56 | |
| 57 | /*----- Functions provided ------------------------------------------------*/ |
| 58 | |
| 59 | /* --- @gfx_add@ --- * |
| 60 | * |
| 61 | * Arguments: @mpw *dv, *dvl@ = destination vector base and limit |
| 62 | * @const mpw *av, *avl@ = first addend vector base and limit |
| 63 | * @const mpw *bv, *bvl@ = second addend vector base and limit |
| 64 | * |
| 65 | * Returns: --- |
| 66 | * |
| 67 | * Use: Adds two %$\gf{2}$% polynomials. This is the same as |
| 68 | * subtraction. |
| 69 | */ |
| 70 | |
| 71 | extern void gfx_add(mpw */*dv*/, mpw */*dvl*/, |
| 72 | const mpw */*av*/, const mpw */*avl*/, |
| 73 | const mpw */*bv*/, const mpw */*bvl*/); |
| 74 | |
| 75 | /* --- @gfx_acc@ --- * |
| 76 | * |
| 77 | * Arguments: @mpw *dv, *dvl@ = destination vector base and limit |
| 78 | * @const mpw *av, *avl@ = addend vector base and limit |
| 79 | * |
| 80 | * Returns: --- |
| 81 | * |
| 82 | * Use: Adds the addend into the destination. This is considerably |
| 83 | * faster than the three-address add call. |
| 84 | */ |
| 85 | |
| 86 | extern void gfx_acc(mpw */*dv*/, mpw */*dvl*/, |
| 87 | const mpw */*av*/, const mpw */*avl*/); |
| 88 | |
| 89 | /* --- @gfx_accshift@ --- * |
| 90 | * |
| 91 | * Arguments: @mpw *dv, *dvl@ = destination vector base and limit |
| 92 | * @const mpw *av, *avl@ = addend vector base and limit |
| 93 | * @size_t n@ = number of bits to shift |
| 94 | * |
| 95 | * Returns: --- |
| 96 | * |
| 97 | * Use: Shifts the argument left by %$n$% places and adds it to the |
| 98 | * destination. This is a primitive used by multiplication and |
| 99 | * division. |
| 100 | */ |
| 101 | |
| 102 | extern void gfx_accshift(mpw */*dv*/, mpw */*dvl*/, |
| 103 | const mpw */*av*/, const mpw */*avl*/, |
| 104 | size_t /*n*/); |
| 105 | |
| 106 | /* --- @gfx_mul@ --- * |
| 107 | * |
| 108 | * Arguments: @mpw *dv, *dvl@ = destination vector base and limit |
| 109 | * @const mpw *av, *avl@ = first argument vector base and limit |
| 110 | * @const mpw *bv, *bvl@ = second argument vector base and limit |
| 111 | * |
| 112 | * Returns: --- |
| 113 | * |
| 114 | * Use: Does multiplication of polynomials over %$\gf{2}$%. |
| 115 | */ |
| 116 | |
| 117 | extern void gfx_mul(mpw */*dv*/, mpw */*dvl*/, |
| 118 | const mpw */*av*/, const mpw */*avl*/, |
| 119 | const mpw */*bv*/, const mpw */*bvl*/); |
| 120 | |
| 121 | /* --- @gfx_sqr@ --- * |
| 122 | * |
| 123 | * Arguments: @mpw *dv, *dvl@ = destination vector base and limit |
| 124 | * @const mpw *av, *avl@ = argument vector base and limit |
| 125 | * |
| 126 | * Returns: --- |
| 127 | * |
| 128 | * Use: Performs squaring of binary polynomials. |
| 129 | */ |
| 130 | |
| 131 | extern void gfx_sqr(mpw */*dv*/, mpw */*dvl*/, |
| 132 | const mpw */*av*/, const mpw */*avl*/); |
| 133 | |
| 134 | /* --- @gfx_div@ --- * |
| 135 | * |
| 136 | * Arguments: @mpw *qv, *qvl@ = quotient vector base and limit |
| 137 | * @mpw *rv, *rvl@ = dividend/remainder vector base and limit |
| 138 | * @const mpw *dv, *dvl@ = divisor vector base and limit |
| 139 | * |
| 140 | * Returns: --- |
| 141 | * |
| 142 | * Use: Performs division on polynomials over %$\gf{2}$%. |
| 143 | */ |
| 144 | |
| 145 | extern void gfx_div(mpw */*qv*/, mpw */*qvl*/, mpw */*rv*/, mpw */*rvl*/, |
| 146 | const mpw */*dv*/, const mpw */*dvl*/); |
| 147 | |
| 148 | /*----- Karatsuba multiplication algorithms -------------------------------*/ |
| 149 | |
| 150 | /* --- @GFK_THRESH@ --- * |
| 151 | * |
| 152 | * This is the limiting length for using Karatsuba algorithms. It's best to |
| 153 | * use the simpler classical multiplication method on numbers smaller than |
| 154 | * this. |
| 155 | */ |
| 156 | |
| 157 | #define GFK_THRESH 2 |
| 158 | |
| 159 | /* --- @gfx_kmul@ --- * |
| 160 | * |
| 161 | * Arguments: @mpw *dv, *dvl@ = pointer to destination buffer |
| 162 | * @const mpw *av, *avl@ = pointer to first argument |
| 163 | * @const mpw *bv, *bvl@ = pointer to second argument |
| 164 | * @mpw *sv, *svl@ = pointer to scratch workspace |
| 165 | * |
| 166 | * Returns: --- |
| 167 | * |
| 168 | * Use: Multiplies two binary polynomials using Karatsuba's |
| 169 | * algorithm. This is rather faster than traditional long |
| 170 | * multiplication (e.g., @gfx_umul@) on polynomials with large |
| 171 | * degree, although more expensive on small ones. |
| 172 | * |
| 173 | * The destination must be twice as large as the larger |
| 174 | * argument. The scratch space must be twice as large as the |
| 175 | * larger argument. |
| 176 | */ |
| 177 | |
| 178 | extern void gfx_kmul(mpw */*dv*/, mpw */*dvl*/, |
| 179 | const mpw */*av*/, const mpw */*avl*/, |
| 180 | const mpw */*bv*/, const mpw */*bvl*/, |
| 181 | mpw */*sv*/, mpw */*svl*/); |
| 182 | |
| 183 | /*----- That's all, folks -------------------------------------------------*/ |
| 184 | |
| 185 | #ifdef __cplusplus |
| 186 | } |
| 187 | #endif |
| 188 | |
| 189 | #endif |