ceb3f0c0 |
1 | /* -*-c-*- |
2 | * |
3 | * $Id: gf.h,v 1.1.2.1 2004/03/21 22:39:46 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 1.1.2.1 2004/03/21 22:39:46 mdw |
34 | * Elliptic curves on binary fields work. |
35 | * |
36 | */ |
37 | |
38 | #ifndef CATACOMB_GF_H |
39 | #define CATACOMB_GF_H |
40 | |
41 | #ifdef __cplusplus |
42 | extern "C" { |
43 | #endif |
44 | |
45 | /*----- Header files ------------------------------------------------------*/ |
46 | |
47 | #ifndef CATACOMB_MP_H |
48 | # include "mp.h" |
49 | #endif |
50 | |
51 | #ifndef CATACOMB_GFX_H |
52 | # include "gfx.h" |
53 | #endif |
54 | |
55 | /*----- Functions provided ------------------------------------------------*/ |
56 | |
57 | /* --- @gf_add@ --- * |
58 | * |
59 | * Arguments: @mp *d@ = destination |
60 | * @mp *a, *b@ = sources |
61 | * |
62 | * Returns: Result, @a@ added to @b@. |
63 | */ |
64 | |
65 | extern mp *gf_add(mp */*d*/, mp */*a*/, mp */*b*/); |
66 | #define gf_sub gf_add |
67 | |
68 | /* --- @gf_mul@ --- * |
69 | * |
70 | * Arguments: @mp *d@ = destination |
71 | * @mp *a, *b@ = sources |
72 | * |
73 | * Returns: Result, @a@ multiplied by @b@. |
74 | */ |
75 | |
76 | extern mp *gf_mul(mp */*d*/, mp */*a*/, mp */*b*/); |
77 | |
78 | /* --- @gf_sqr@ --- * |
79 | * |
80 | * Arguments: @mp *d@ = destination |
81 | * @mp *a@ = source |
82 | * |
83 | * Returns: Result, @a@ squared. |
84 | */ |
85 | |
86 | extern mp *gf_sqr(mp */*d*/, mp */*a*/); |
87 | |
88 | /* --- @gf_div@ --- * |
89 | * |
90 | * Arguments: @mp **qq, **rr@ = destination, quotient and remainder |
91 | * @mp *a, *b@ = sources |
92 | * |
93 | * Use: Calculates the quotient and remainder when @a@ is divided by |
94 | * @b@. The destinations @*qq@ and @*rr@ must be distinct. |
95 | * Either of @qq@ or @rr@ may be null to indicate that the |
96 | * result is irrelevant. (Discarding both results is silly.) |
97 | * There is a performance advantage if @a == *rr@. |
98 | */ |
99 | |
100 | extern void gf_div(mp **/*qq*/, mp **/*rr*/, mp */*a*/, mp */*b*/); |
101 | |
102 | /* --- @gf_gcd@ --- * |
103 | * |
104 | * Arguments: @mp **gcd, **xx, **yy@ = where to write the results |
105 | * @mp *a, *b@ = sources (must be nonzero) |
106 | * |
107 | * |
108 | * Returns: --- |
109 | * |
110 | * Use: Calculates @gcd(a, b)@, and two numbers @x@ and @y@ such that |
111 | * @ax + by = gcd(a, b)@. This is useful for computing modular |
112 | * inverses. |
113 | */ |
114 | |
115 | extern void gf_gcd(mp **/*gcd*/, mp **/*xx*/, mp **/*yy*/, |
116 | mp */*a*/, mp */*b*/); |
117 | |
118 | /*----- That's all, folks -------------------------------------------------*/ |
119 | |
120 | #ifdef __cplusplus |
121 | } |
122 | #endif |
123 | |
124 | #endif |