3 * $Id: field.h,v 1.1 2001/04/29 18:12:33 mdw Exp $
5 * Definitions for field arithmetic
7 * (c) 2000 Straylight/Edgeware
10 /*----- Licensing notice --------------------------------------------------*
12 * This file is part of Catacomb.
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.
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.
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,
30 /*----- Revision history --------------------------------------------------*
33 * Revision 1.1 2001/04/29 18:12:33 mdw
38 #ifndef CATACOMB_FIELD_H
39 #define CATACOMB_FIELD_H
45 /*----- Header files ------------------------------------------------------*/
51 /*----- Data structures ---------------------------------------------------*/
53 typedef struct field
{
54 const struct field_ops
*ops
; /* Field operations */
55 mp
*zero
, *one
; /* Identities in the field */
58 typedef struct field_ops
{
60 /* --- Universal operations --- */
62 void (*destroy
)(field */
*f*/
);
64 mp
*(*in
)(field */
*f*/
, mp */
*d*/
, mp */
*x*/
);
65 mp
*(*out
)(field */
*f*/
, mp */
*d*/
, mp */
*x*/
);
67 mp
*(*add
)(field */
*f*/
, mp */
*d*/
, mp */
*x*/
, mp */
*y*/
);
68 mp
*(*sub
)(field */
*f*/
, mp */
*d*/
, mp */
*x*/
, mp */
*y*/
);
69 mp
*(*mul
)(field */
*f*/
, mp */
*d*/
, mp */
*x*/
, mp */
*y*/
);
70 mp
*(*sqr
)(field */
*f*/
, mp */
*d*/
, mp */
*x*/
);
71 mp
*(*inv
)(field */
*f*/
, mp */
*d*/
, mp */
*x*/
);
72 mp
*(*reduce
)(field */
*f*/
, mp */
*d*/
, mp */
*x*/
);
74 /* --- Operations for prime fields only --- */
76 mp
*(*dbl
)(field */
*f*/
, mp */
*d*/
, mp */
*x*/
);
77 mp
*(*tpl
)(field */
*f*/
, mp */
*d*/
, mp */
*x*/
);
78 mp
*(*sqrt
)(field */
*f*/
, mp */
*d*/
, mp */
*x*/
);
82 #define F_DESTROY(f) (f)->ops->destroy((f))
84 #define F_IN(f, d, x) (f)->ops->in((f), (d), (x))
85 #define F_OUT(f, d, x) (f)->ops->out((f), (d), (x))
86 #define F_ADD(f, d, x, y) (f)->ops->add((f), (d), (x), (y))
87 #define F_SUB(f, d, x, y) (f)->ops->sub((f), (d), (x), (y))
88 #define F_MUL(f, d, x, y) (f)->ops->mul((f), (d), (x), (y))
89 #define F_SQR(f, d, x) (f)->ops->sqr((f), (d), (x))
90 #define F_INV(f, d, x) (f)->ops->inv((f), (d), (x))
91 #define F_REDUCE(f, d, x) (f)->ops->reduce((f), (d), (x))
93 #define F_DBL(f, d, x) (f)->ops->dbl((f), (d), (x))
94 #define F_TPL(f, d, x) (f)->ops->tpl((f), (d), (x))
95 #define F_SQRT(f, d, x) (f)->ops->sqrt((f), (d), (x))
97 /*----- Creating fields ---------------------------------------------------*/
99 /* --- @field_prime@ --- *
101 * Arguments: @mp *p@ = the characteristic of the field
103 * Returns: A pointer to the field.
105 * Use: Creates a field structure for a prime field of size %$p$%,
106 * using Montgomery reduction for arithmetic.
109 extern field
*field_prime(mp */
*p*/
);
111 /* --- @field_binpoly@ --- *
113 * Arguments: @mp *p@ = an irreducible polynomial over %$\gf{2}$%
115 * Returns: A pointer to the field.
117 * Use: Creates a field structure for a binary field using naive
121 extern field
*field_binpoly(mp */
*p*/
);
123 /* --- @field_binsparsepoly@ --- *
125 * Arguments: @unsigned deg@ = the degree of the field polynomial
126 * @const unsigned *c@ = degrees of nonzero coefficients
128 * Returns: A pointer to the field.
130 * Use: Creates a field structure for a binary field taking advantage
131 * of the sparseness of the given polynomial to improve
132 * reduction performance.
135 extern field
*field_binsparsepoly(unsigned /*deg*/, const unsigned */
*c*/
);
137 /*----- That's all, folks -------------------------------------------------*/