3 * $Id: ec-prime.c,v 1.1 2001/04/29 18:12:33 mdw Exp $
5 * Elliptic curves over prime fields
7 * (c) 2001 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 --------------------------------------------------*
32 * $Log: ec-prime.c,v $
33 * Revision 1.1 2001/04/29 18:12:33 mdw
38 /*----- Header files ------------------------------------------------------*/
42 /*----- Data structures ---------------------------------------------------*/
44 typedef struct ecctx
{
49 /*----- Main code ---------------------------------------------------------*/
51 static void ecadd(ec_curve
*c
, ec
*d
, const ec
*a
, const ec
*b
)
53 /* --- Deal with the simple cases --- */
61 else if (MP_EQ(a
->x
, b
->x
) && MP_EQ(a
->z
, b
->z
)) {
62 if ((a
->y
->f
^ b
->y
->f
) & MP_NEG
)
72 /*----- That's all, folks -------------------------------------------------*/