chiark - git - mdw - catacomb/blob - des-base.h

   1 /* -*-c-*-
   2  *
   3  * $Id: des-base.h,v 1.4 2004/04/08 01:36:15 mdw Exp $
   4  *
   5  * Common features for DES implementation
   6  *
   7  * (c) 1999 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 #ifndef CATACOMB_DES_BASE_H
  31 #define CATACOMB_DES_BASE_H
  32
  33 #ifdef __cplusplus
  34   extern "C" {
  35 #endif
  36
  37 /*----- Header files ------------------------------------------------------*/
  38
  39 #include <mLib/bits.h>
  40
  41 /*----- External data -----------------------------------------------------*/
  42
  43 extern const uint32 des_sp[8][64];
  44
  45 /*----- Macros ------------------------------------------------------------*/
  46
  47 /* --- @DES_ROUND@ --- *
  48  *
  49  * This is the basic DES round function.  The inputs are the two subkey
  50  * halves, and the left and right block halves.  Note that the block halves
  51  * are rotated left one place at this point.  This wraps what's meant to be
  52  * the top bit around to the bottom, so I get a clear run at the S-boxes.
  53  */
  54
  55 #define DES_ROUND(ka, kb, x, y) do {                                    \
  56   uint32 _t = (y) ^ (ka);                                               \
  57   (x) ^= des_sp[7][(_t >>  0) & 0x3f] ^                                 \
  58          des_sp[5][(_t >>  8) & 0x3f] ^                                 \
  59          des_sp[3][(_t >> 16) & 0x3f] ^                                 \
  60          des_sp[1][(_t >> 24) & 0x3f];                                  \
  61   _t = ROR32((y), 4) ^ (kb);                                            \
  62   (x) ^= des_sp[6][(_t >>  0) & 0x3f] ^                                 \
  63          des_sp[4][(_t >>  8) & 0x3f] ^                                 \
  64          des_sp[2][(_t >> 16) & 0x3f] ^                                 \
  65          des_sp[0][(_t >> 24) & 0x3f];                                  \
  66 } while (0)
  67
  68 /* --- @DES_IP@, @DES_IPINV@ --- *
  69  *
  70  * The cryptographically useless initial and final permutations.  The initial
  71  * permutation also rotates the two block halves left by one place.  This is
  72  * undone by the inverse permutation at the end.
  73  */
  74
  75 #define DES_IP(x, y) do {                                               \
  76   uint32 _t;                                                            \
  77   _t = (y ^ (x >> 4)) & 0x0f0f0f0f; y ^= _t; x ^= _t << 4;              \
  78   _t = (x ^ (x >> 18)) & 0x00003333; x ^= _t; x ^= _t << 18;            \
  79   _t = (y ^ (y >> 18)) & 0x00003333; y ^= _t; y ^= _t << 18;            \
  80   _t = (x ^ (x >> 9)) & 0x00550055; x ^= _t; x ^= _t << 9;              \
  81   _t = (y ^ (y >> 9)) & 0x00550055; y ^= _t; y ^= _t << 9;              \
  82   _t = (x ^ (x >> 24)) & 0x000000ff; x ^= _t; x ^= _t << 24;            \
  83   _t = (y ^ (y >> 24)) & 0x000000ff; y ^= _t; y ^= _t << 24;            \
  84   _t = (y ^ (x >> 16)) & 0x0000ffff; y ^= _t; x ^= _t << 16;            \
  85   x = ROL32(x, 1); y = ROL32(y, 1);                                     \
  86 } while (0)
  87
  88 #define DES_IPINV(x, y) do {                                            \
  89   uint32 _t;                                                            \
  90   x = ROR32(x, 1); y = ROR32(y, 1);                                     \
  91   _t = (y ^ (x >> 16)) & 0x0000ffff; y ^= _t; x ^= _t << 16;            \
  92   _t = (x ^ (x >> 24)) & 0x000000ff; x ^= _t; x ^= _t << 24;            \
  93   _t = (y ^ (y >> 24)) & 0x000000ff; y ^= _t; y ^= _t << 24;            \
  94   _t = (y ^ (x >> 4)) & 0x0f0f0f0f; y ^= _t; x ^= _t << 4;              \
  95   _t = (x ^ (x >> 18)) & 0x00003333; x ^= _t; x ^= _t << 18;            \
  96   _t = (y ^ (y >> 18)) & 0x00003333; y ^= _t; y ^= _t << 18;            \
  97   _t = (x ^ (x >> 9)) & 0x00550055; x ^= _t; x ^= _t << 9;              \
  98   _t = (y ^ (y >> 9)) & 0x00550055; y ^= _t; y ^= _t << 9;              \
  99 } while (0)
 100
 101 /* --- @DES_EBLK@, @DES_DBLK@ --- *
 102  *
 103  * Whole block encryption and decryption.
 104  */
 105
 106 #define DES_EBLK(k, a, b, c, d) do {                                    \
 107   const uint32 *_k = (k);                                               \
 108   uint32 _x = (a), _y = (b);                                            \
 109   DES_ROUND(_k[0], _k[1], _x, _y); _k += 2;                             \
 110   DES_ROUND(_k[0], _k[1], _y, _x); _k += 2;                             \
 111   DES_ROUND(_k[0], _k[1], _x, _y); _k += 2;                             \
 112   DES_ROUND(_k[0], _k[1], _y, _x); _k += 2;                             \
 113   DES_ROUND(_k[0], _k[1], _x, _y); _k += 2;                             \
 114   DES_ROUND(_k[0], _k[1], _y, _x); _k += 2;                             \
 115   DES_ROUND(_k[0], _k[1], _x, _y); _k += 2;                             \
 116   DES_ROUND(_k[0], _k[1], _y, _x); _k += 2;                             \
 117   DES_ROUND(_k[0], _k[1], _x, _y); _k += 2;                             \
 118   DES_ROUND(_k[0], _k[1], _y, _x); _k += 2;                             \
 119   DES_ROUND(_k[0], _k[1], _x, _y); _k += 2;                             \
 120   DES_ROUND(_k[0], _k[1], _y, _x); _k += 2;                             \
 121   DES_ROUND(_k[0], _k[1], _x, _y); _k += 2;                             \
 122   DES_ROUND(_k[0], _k[1], _y, _x); _k += 2;                             \
 123   DES_ROUND(_k[0], _k[1], _x, _y); _k += 2;                             \
 124   DES_ROUND(_k[0], _k[1], _y, _x); _k += 2;                             \
 125   (c) = _y;                                                             \
 126   (d) = _x;                                                             \
 127 } while (0)
 128
 129 #define DES_DBLK(k, a, b, c, d) do {                                    \
 130   const uint32 *_k = (k) + 32;                                          \
 131   uint32 _x = (a), _y = (b);                                            \
 132   _k -= 2; DES_ROUND(_k[0], _k[1], _x, _y);                             \
 133   _k -= 2; DES_ROUND(_k[0], _k[1], _y, _x);                             \
 134   _k -= 2; DES_ROUND(_k[0], _k[1], _x, _y);                             \
 135   _k -= 2; DES_ROUND(_k[0], _k[1], _y, _x);                             \
 136   _k -= 2; DES_ROUND(_k[0], _k[1], _x, _y);                             \
 137   _k -= 2; DES_ROUND(_k[0], _k[1], _y, _x);                             \
 138   _k -= 2; DES_ROUND(_k[0], _k[1], _x, _y);                             \
 139   _k -= 2; DES_ROUND(_k[0], _k[1], _y, _x);                             \
 140   _k -= 2; DES_ROUND(_k[0], _k[1], _x, _y);                             \
 141   _k -= 2; DES_ROUND(_k[0], _k[1], _y, _x);                             \
 142   _k -= 2; DES_ROUND(_k[0], _k[1], _x, _y);                             \
 143   _k -= 2; DES_ROUND(_k[0], _k[1], _y, _x);                             \
 144   _k -= 2; DES_ROUND(_k[0], _k[1], _x, _y);                             \
 145   _k -= 2; DES_ROUND(_k[0], _k[1], _y, _x);                             \
 146   _k -= 2; DES_ROUND(_k[0], _k[1], _x, _y);                             \
 147   _k -= 2; DES_ROUND(_k[0], _k[1], _y, _x);                             \
 148   (c) = _y;                                                             \
 149   (d) = _x;                                                             \
 150 } while (0)
 151
 152 /*----- That's all, folks -------------------------------------------------*/
 153
 154 #ifdef __cplusplus
 155   }
 156 #endif
 157
 158 #endif