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   1 /* -*-c-*-
   2  *
   3  * $Id: twofish.h,v 1.2 2000/10/08 15:48:58 mdw Exp $
   4  *
   5  * The Twofish block cipher
   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: twofish.h,v $
  33  * Revision 1.2  2000/10/08 15:48:58  mdw
  34  * Update comments now that AES has been chosen.
  35  *
  36  * Revision 1.1  2000/06/17 12:10:17  mdw
  37  * New cipher.
  38  *
  39  */
  40
  41 /*----- Notes on the Twofish block cipher ---------------------------------*
  42  *
  43  * Twofish was designed by Bruce Schneier, John Kelsey, Doug Whiting, David
  44  * Wagner, Chris Hall and Niels Ferguson.  The algorithm is unpatented and
  45  * free for anyone to use.  It was one of the five AES finalist algorithms.
  46  *
  47  * Twofish is a complex cipher offering various space and time tradeoffs.
  48  * This implementation has a heavy key schedule and fast bulk encryption.
  49  */
  50
  51 #ifndef CATACOMB_TWOFISH_H
  52 #define CATACOMB_TWOFISH_H
  53
  54 #ifdef __cplusplus
  55   extern "C" {
  56 #endif
  57
  58 /*----- Header files ------------------------------------------------------*/
  59
  60 #include <stddef.h>
  61
  62 #include <mLib/bits.h>
  63
  64 /*----- Magical numbers ---------------------------------------------------*/
  65
  66 #define TWOFISH_BLKSZ 16
  67 #define TWOFISH_KEYSZ 32
  68 #define TWOFISH_CLASS (N, L, 128)
  69
  70 extern const octet twofish_keysz[];
  71
  72 /*----- Data structures ---------------------------------------------------*/
  73
  74 typedef struct twofish_ctx {
  75   uint32 k[40];
  76   uint32 g[4][256];
  77 } twofish_ctx;
  78
  79 /*----- Functions provided ------------------------------------------------*/
  80
  81 /* --- @twofish_init@ --- *
  82  *
  83  * Arguments:   @twofish_ctx *k@ = pointer to key block to fill in
  84  *              @const void *buf@ = pointer to buffer of key material
  85  *              @size_t sz@ = size of key material
  86  *
  87  * Returns:     ---
  88  *
  89  * Use:         Initializes a Twofish key buffer.  Twofish accepts keys of up
  90  *              to 256 bits in length.
  91  */
  92
  93 extern void twofish_init(twofish_ctx */*k*/,
  94                          const void */*buf*/, size_t /*sz*/);
  95
  96 /* --- @twofish_eblk@, @twofish_dblk@ --- *
  97  *
  98  * Arguments:   @const twofish_ctx *k@ = pointer to key block
  99  *              @const uint32 s[4]@ = pointer to source block
 100  *              @uint32 d[4]@ = pointer to destination block
 101  *
 102  * Returns:     ---
 103  *
 104  * Use:         Low-level block encryption and decryption.
 105  */
 106
 107 extern void twofish_eblk(const twofish_ctx */*k*/,
 108                          const uint32 */*s*/, uint32 */*d*/);
 109
 110 extern void twofish_dblk(const twofish_ctx */*k*/,
 111                           const uint32 */*s*/, uint32 */*d*/);
 112
 113 /*----- That's all, folks -------------------------------------------------*/
 114
 115 #ifdef __cplusplus
 116   }
 117 #endif
 118
 119 #endif