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   1 /* -*-c-*-
   2  *
   3  * $Id: des-base.h,v 1.1 1999/09/03 08:41:11 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 /*----- Revision history --------------------------------------------------*
  31  *
  32  * $Log: des-base.h,v $
  33  * Revision 1.1  1999/09/03 08:41:11  mdw
  34  * Initial import.
  35  *
  36  */
  37
  38 #ifndef DES_BASE_H
  39 #define DES_BASE_H
  40
  41 #ifdef __cplusplus
  42   extern "C" {
  43 #endif
  44
  45 /*----- Header files ------------------------------------------------------*/
  46
  47 #include <mLib/bits.h>
  48
  49 /*----- External data -----------------------------------------------------*/
  50
  51 extern uint32 des_sp[8][64];
  52
  53 /*----- Macros ------------------------------------------------------------*/
  54
  55 /* --- @DES_ROUND@ --- *
  56  *
  57  * This is the basic DES round function.  The inputs are the two subkey
  58  * halves, and the left and right block halves.  Note that the block halves
  59  * are rotated left one place at this point.  This wraps what's meant to be
  60  * the top bit around to the bottom, so I get a clear run at the S-boxes.
  61  */
  62
  63 #define DES_ROUND(ka, kb, x, y) do {                                    \
  64   uint32 _t = (y) ^ (ka);                                               \
  65   (x) ^= des_sp[7][(_t >>  0) & 0x3f] ^                                 \
  66          des_sp[5][(_t >>  8) & 0x3f] ^                                 \
  67          des_sp[3][(_t >> 16) & 0x3f] ^                                 \
  68          des_sp[1][(_t >> 24) & 0x3f];                                  \
  69   _t = ROR32((y), 4) ^ (kb);                                            \
  70   (x) ^= des_sp[6][(_t >>  0) & 0x3f] ^                                 \
  71          des_sp[4][(_t >>  8) & 0x3f] ^                                 \
  72          des_sp[2][(_t >> 16) & 0x3f] ^                                 \
  73          des_sp[0][(_t >> 24) & 0x3f];                                  \
  74 } while (0)
  75
  76 /* --- @DES_IP@, @DES_IPINV@ --- *
  77  *
  78  * The cryptographically useless initial and final permutations.  The initial
  79  * permutation also rotates the two block halves left by one place.  This is
  80  * undone by the inverse permutation at the end.
  81  */
  82
  83 #define DES_IP(x, y) do {                                               \
  84   uint32 _t;                                                            \
  85   _t = (y ^ (x >> 4)) & 0x0f0f0f0f; y ^= _t; x ^= _t << 4;              \
  86   _t = (x ^ (x >> 18)) & 0x00003333; x ^= _t; x ^= _t << 18;            \
  87   _t = (y ^ (y >> 18)) & 0x00003333; y ^= _t; y ^= _t << 18;            \
  88   _t = (x ^ (x >> 9)) & 0x00550055; x ^= _t; x ^= _t << 9;              \
  89   _t = (y ^ (y >> 9)) & 0x00550055; y ^= _t; y ^= _t << 9;              \
  90   _t = (x ^ (x >> 24)) & 0x000000ff; x ^= _t; x ^= _t << 24;            \
  91   _t = (y ^ (y >> 24)) & 0x000000ff; y ^= _t; y ^= _t << 24;            \
  92   _t = (y ^ (x >> 16)) & 0x0000ffff; y ^= _t; x ^= _t << 16;            \
  93   x = ROL32(x, 1); y = ROL32(y, 1);                                     \
  94 } while (0)
  95
  96 #define DES_IPINV(x, y) do {                                            \
  97   uint32 _t;                                                            \
  98   x = ROR32(x, 1); y = ROR32(y, 1);                                     \
  99   _t = (y ^ (x >> 16)) & 0x0000ffff; y ^= _t; x ^= _t << 16;            \
 100   _t = (x ^ (x >> 24)) & 0x000000ff; x ^= _t; x ^= _t << 24;            \
 101   _t = (y ^ (y >> 24)) & 0x000000ff; y ^= _t; y ^= _t << 24;            \
 102   _t = (y ^ (x >> 4)) & 0x0f0f0f0f; y ^= _t; x ^= _t << 4;              \
 103   _t = (x ^ (x >> 18)) & 0x00003333; x ^= _t; x ^= _t << 18;            \
 104   _t = (y ^ (y >> 18)) & 0x00003333; y ^= _t; y ^= _t << 18;            \
 105   _t = (x ^ (x >> 9)) & 0x00550055; x ^= _t; x ^= _t << 9;              \
 106   _t = (y ^ (y >> 9)) & 0x00550055; y ^= _t; y ^= _t << 9;              \
 107 } while (0)
 108
 109 /* --- @DES_EBLK@, @DES_DBLK@ --- *
 110  *
 111  * Whole block encryption and decryption.
 112  */
 113
 114 #define DES_EBLK(k, a, b, c, d) do {                                    \
 115   const uint32 *_k = (k);                                               \
 116   uint32 _x = (a), _y = (b);                                            \
 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   DES_ROUND(_k[0], _k[1], _x, _y); _k += 2;                             \
 126   DES_ROUND(_k[0], _k[1], _y, _x); _k += 2;                             \
 127   DES_ROUND(_k[0], _k[1], _x, _y); _k += 2;                             \
 128   DES_ROUND(_k[0], _k[1], _y, _x); _k += 2;                             \
 129   DES_ROUND(_k[0], _k[1], _x, _y); _k += 2;                             \
 130   DES_ROUND(_k[0], _k[1], _y, _x); _k += 2;                             \
 131   DES_ROUND(_k[0], _k[1], _x, _y); _k += 2;                             \
 132   DES_ROUND(_k[0], _k[1], _y, _x); _k += 2;                             \
 133   (c) = _y;                                                             \
 134   (d) = _x;                                                             \
 135 } while (0)
 136
 137 #define DES_DBLK(k, a, b, c, d) do {                                    \
 138   const uint32 *_k = (k) + 32;                                          \
 139   uint32 _x = (a), _y = (b);                                            \
 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   _k -= 2; DES_ROUND(_k[0], _k[1], _x, _y);                             \
 149   _k -= 2; DES_ROUND(_k[0], _k[1], _y, _x);                             \
 150   _k -= 2; DES_ROUND(_k[0], _k[1], _x, _y);                             \
 151   _k -= 2; DES_ROUND(_k[0], _k[1], _y, _x);                             \
 152   _k -= 2; DES_ROUND(_k[0], _k[1], _x, _y);                             \
 153   _k -= 2; DES_ROUND(_k[0], _k[1], _y, _x);                             \
 154   _k -= 2; DES_ROUND(_k[0], _k[1], _x, _y);                             \
 155   _k -= 2; DES_ROUND(_k[0], _k[1], _y, _x);                             \
 156   (c) = _y;                                                             \
 157   (d) = _x;                                                             \
 158 } while (0)
 159
 160 /*----- That's all, folks -------------------------------------------------*/
 161
 162 #ifdef __cplusplus
 163   }
 164 #endif
 165
 166 #endif