git.distorted.org.uk Git - u/mdw/catacomb/blob - symm/blowfish.h

   1 /* -*-c-*-
   2  *
   3  * The Blowfish block cipher
   4  *
   5  * (c) 1998 Straylight/Edgeware
   6  */
   7
   8 /*----- Licensing notice --------------------------------------------------*
   9  *
  10  * This file is part of Catacomb.
  11  *
  12  * Catacomb is free software; you can redistribute it and/or modify
  13  * it under the terms of the GNU Library General Public License as
  14  * published by the Free Software Foundation; either version 2 of the
  15  * License, or (at your option) any later version.
  16  *
  17  * Catacomb is distributed in the hope that it will be useful,
  18  * but WITHOUT ANY WARRANTY; without even the implied warranty of
  19  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  20  * GNU Library General Public License for more details.
  21  *
  22  * You should have received a copy of the GNU Library General Public
  23  * License along with Catacomb; if not, write to the Free
  24  * Software Foundation, Inc., 59 Temple Place - Suite 330, Boston,
  25  * MA 02111-1307, USA.
  26  */
  27
  28 /*----- Notes on the Blowfish block cipher --------------------------------*
  29  *
  30  * Blowfish was invented by Bruce Schneier.  The algorithm is unpatented and
  31  * free for anyone to use.  It's fast, simple, offers a big key, and is
  32  * looking relatively bulletproof.  It's also this author's block cipher of
  33  * choice, for what little that's worth.  The disadvantage is that Blowfish
  34  * has a particularly heavyweight key schedule.
  35  */
  36
  37 #ifndef CATACOMB_BLOWFISH_H
  38 #define CATACOMB_BLOWFISH_H
  39
  40 #ifdef __cplusplus
  41   extern "C" {
  42 #endif
  43
  44 /*----- Header files ------------------------------------------------------*/
  45
  46 #include <stddef.h>
  47
  48 #include <mLib/bits.h>
  49
  50 /*----- Magical numbers ---------------------------------------------------*/
  51
  52 #define BLOWFISH_BLKSZ 8
  53 #define BLOWFISH_KEYSZ 32
  54 #define BLOWFISH_CLASS (N, B, 64)
  55
  56 extern const octet blowfish_keysz[];
  57
  58 /*----- Data structures ---------------------------------------------------*/
  59
  60 typedef struct blowfish_ctx {
  61   uint32 p[18];
  62   uint32 s0[256], s1[256], s2[256], s3[256];
  63 } blowfish_ctx;
  64
  65 /*----- Functions provided ------------------------------------------------*/
  66
  67 /* --- @blowfish_init@ --- *
  68  *
  69  * Arguments:   @blowfish_ctx *k@ = pointer to key block to fill in
  70  *              @const void *buf@ = pointer to buffer of key material
  71  *              @size_t sz@ = size of key material
  72  *
  73  * Returns:     ---
  74  *
  75  * Use:         Initializes a Blowfish key buffer.  Blowfish accepts
  76  *              a more-or-less arbitrary size key.
  77  */
  78
  79 extern void blowfish_init(blowfish_ctx */*k*/,
  80                           const void */*buf*/, size_t /*sz*/);
  81
  82 /* --- @blowfish_eblk@, @blowfish_dblk@ --- *
  83  *
  84  * Arguments:   @const blowfish_ctx *k@ = pointer to key block
  85  *              @const uint32 s[2]@ = pointer to source block
  86  *              @uint32 d[2]@ = pointer to destination block
  87  *
  88  * Returns:     ---
  89  *
  90  * Use:         Low-level block encryption and decryption.
  91  */
  92
  93 extern void blowfish_eblk(const blowfish_ctx */*k*/,
  94                           const uint32 */*s*/, uint32 */*d*/);
  95
  96 extern void blowfish_dblk(const blowfish_ctx */*k*/,
  97                           const uint32 */*s*/, uint32 */*d*/);
  98
  99 /*----- That's all, folks -------------------------------------------------*/
 100
 101 #ifdef __cplusplus
 102   }
 103 #endif
 104
 105 #endif