| 1 | /* -*-c-*- |
| 2 | * |
| 3 | * $Id: gf.h,v 1.3 2004/03/27 17:54:11 mdw Exp $ |
| 4 | * |
| 5 | * Arithmetic on binary polynomials |
| 6 | * |
| 7 | * (c) 2004 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: gf.h,v $ |
| 33 | * Revision 1.3 2004/03/27 17:54:11 mdw |
| 34 | * Standard curves and curve checking. |
| 35 | * |
| 36 | * Revision 1.2 2004/03/21 22:52:06 mdw |
| 37 | * Merge and close elliptic curve branch. |
| 38 | * |
| 39 | * Revision 1.1.2.1 2004/03/21 22:39:46 mdw |
| 40 | * Elliptic curves on binary fields work. |
| 41 | * |
| 42 | */ |
| 43 | |
| 44 | #ifndef CATACOMB_GF_H |
| 45 | #define CATACOMB_GF_H |
| 46 | |
| 47 | #ifdef __cplusplus |
| 48 | extern "C" { |
| 49 | #endif |
| 50 | |
| 51 | /*----- Header files ------------------------------------------------------*/ |
| 52 | |
| 53 | #ifndef CATACOMB_MP_H |
| 54 | # include "mp.h" |
| 55 | #endif |
| 56 | |
| 57 | #ifndef CATACOMB_GFX_H |
| 58 | # include "gfx.h" |
| 59 | #endif |
| 60 | |
| 61 | /*----- Functions provided ------------------------------------------------*/ |
| 62 | |
| 63 | /* --- @gf_add@ --- * |
| 64 | * |
| 65 | * Arguments: @mp *d@ = destination |
| 66 | * @mp *a, *b@ = sources |
| 67 | * |
| 68 | * Returns: Result, @a@ added to @b@. |
| 69 | */ |
| 70 | |
| 71 | extern mp *gf_add(mp */*d*/, mp */*a*/, mp */*b*/); |
| 72 | #define gf_sub gf_add |
| 73 | |
| 74 | /* --- @gf_mul@ --- * |
| 75 | * |
| 76 | * Arguments: @mp *d@ = destination |
| 77 | * @mp *a, *b@ = sources |
| 78 | * |
| 79 | * Returns: Result, @a@ multiplied by @b@. |
| 80 | */ |
| 81 | |
| 82 | extern mp *gf_mul(mp */*d*/, mp */*a*/, mp */*b*/); |
| 83 | |
| 84 | /* --- @gf_sqr@ --- * |
| 85 | * |
| 86 | * Arguments: @mp *d@ = destination |
| 87 | * @mp *a@ = source |
| 88 | * |
| 89 | * Returns: Result, @a@ squared. |
| 90 | */ |
| 91 | |
| 92 | extern mp *gf_sqr(mp */*d*/, mp */*a*/); |
| 93 | |
| 94 | /* --- @gf_div@ --- * |
| 95 | * |
| 96 | * Arguments: @mp **qq, **rr@ = destination, quotient and remainder |
| 97 | * @mp *a, *b@ = sources |
| 98 | * |
| 99 | * Use: Calculates the quotient and remainder when @a@ is divided by |
| 100 | * @b@. The destinations @*qq@ and @*rr@ must be distinct. |
| 101 | * Either of @qq@ or @rr@ may be null to indicate that the |
| 102 | * result is irrelevant. (Discarding both results is silly.) |
| 103 | * There is a performance advantage if @a == *rr@. |
| 104 | */ |
| 105 | |
| 106 | extern void gf_div(mp **/*qq*/, mp **/*rr*/, mp */*a*/, mp */*b*/); |
| 107 | |
| 108 | /* --- @gf_irreduciblep@ --- * |
| 109 | * |
| 110 | * Arguments: @mp *f@ = a polynomial |
| 111 | * |
| 112 | * Returns: Nonzero if the polynomial is irreducible; otherwise zero. |
| 113 | */ |
| 114 | |
| 115 | extern int gf_irreduciblep(mp */*f*/); |
| 116 | |
| 117 | /* --- @gf_gcd@ --- * |
| 118 | * |
| 119 | * Arguments: @mp **gcd, **xx, **yy@ = where to write the results |
| 120 | * @mp *a, *b@ = sources (must be nonzero) |
| 121 | * |
| 122 | * |
| 123 | * Returns: --- |
| 124 | * |
| 125 | * Use: Calculates @gcd(a, b)@, and two numbers @x@ and @y@ such that |
| 126 | * @ax + by = gcd(a, b)@. This is useful for computing modular |
| 127 | * inverses. |
| 128 | */ |
| 129 | |
| 130 | extern void gf_gcd(mp **/*gcd*/, mp **/*xx*/, mp **/*yy*/, |
| 131 | mp */*a*/, mp */*b*/); |
| 132 | |
| 133 | /*----- That's all, folks -------------------------------------------------*/ |
| 134 | |
| 135 | #ifdef __cplusplus |
| 136 | } |
| 137 | #endif |
| 138 | |
| 139 | #endif |