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   1 /* -*-c-*-
   2  *
   3  * $Id: desx.h,v 1.1 2001/04/03 19:36:50 mdw Exp $
   4  *
   5  * The DESX algorithm
   6  *
   7  * (c) 2001 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: desx.h,v $
  33  * Revision 1.1  2001/04/03 19:36:50  mdw
  34  * New block cipher DESX added.
  35  *
  36  */
  37
  38 /*----- Notes on DESX -----------------------------------------------------*
  39  *
  40  * DESX was designed by Ron Rivest in 1986 as a simple and cheap way to
  41  * strengthen DES against exhaustive search.  It also increases the
  42  * difficulty of differential and linear attacks.
  43  */
  44
  45 #ifndef CATACOMB_DESX_H
  46 #define CATACOMB_DESX_H
  47
  48 #ifdef __cplusplus
  49   extern "C" {
  50 #endif
  51
  52 /*----- Header files ------------------------------------------------------*/
  53
  54 #include <stddef.h>
  55
  56 #include <mLib/bits.h>
  57
  58 #ifndef CATACOMB_DES_H
  59 #  include "des.h"
  60 #endif
  61
  62 /*----- Magical numbers ---------------------------------------------------*/
  63
  64 #define DESX_BLKSZ 8
  65 #define DESX_KEYSZ 23
  66 #define DESX_CLASS (N, B, 64)
  67
  68 extern const octet desx_keysz[];
  69
  70 /*----- Data structures ---------------------------------------------------*/
  71
  72 typedef struct desx_ctx {
  73   des_ctx k;
  74   uint32 prea, preb;
  75   uint32 posta, postb;
  76 } desx_ctx;
  77
  78 /*----- Functions provided ------------------------------------------------*/
  79
  80 /* --- @desx_init@ --- *
  81  *
  82  * Arguments:   @desx_ctx *k@ = pointer to key block
  83  *              @const void *buf@ = pointer to key buffer
  84  *              @size_t sz@ = size of key material
  85  *
  86  * Returns:     ---
  87  *
  88  * Use:         Initializes a DESX key buffer.  The key buffer contains, in
  89  *              order, an optional 8-byte pre-whitening key, a single-DES key
  90  *              (either 7 or 8 bytes), and an optional 8-byte port-whitening
  91  *              key.  If no whitening keys are specified, the algorithm
  92  *              becomes the same as single-DES.
  93  */
  94
  95 extern void desx_init(desx_ctx */*k*/, const void */*buf*/, size_t /*sz*/);
  96
  97 /* --- @desx_eblk@, @desx_dblk@ --- *
  98  *
  99  * Arguments:   @const desx_ctx *k@ = pointer to key block
 100  *              @const uint32 s[2]@ = pointer to source block
 101  *              @uint32 d[2]@ = pointer to destination block
 102  *
 103  * Returns:     ---
 104  *
 105  * Use:         Low-level block encryption and decryption.
 106  */
 107
 108 extern void desx_eblk(const desx_ctx */*k*/,
 109                       const uint32 */*s*/, uint32 */*d*/);
 110 extern void desx_dblk(const desx_ctx */*k*/,
 111                       const uint32 */*s*/, uint32 */*d*/);
 112
 113 /*----- That's all, folks -------------------------------------------------*/
 114
 115 #ifdef __cplusplus
 116   }
 117 #endif
 118
 119 #endif