crypto/serpent.c

   1 /*
   2  * Cryptographic API.
   3  *
   4  * Serpent Cipher Algorithm.
   5  *
   6  * Copyright (C) 2002 Dag Arne Osvik <osvik@ii.uib.no>
   7  *               2003 Herbert Valerio Riedel <hvr@gnu.org>
   8  *
   9  * Added tnepres support: Ruben Jesus Garcia Hernandez <ruben@ugr.es>, 18.10.2004
  10  *               Based on code by hvr
  11  *
  12  * This program is free software; you can redistribute it and/or modify
  13  * it under the terms of the GNU General Public License as published by
  14  * the Free Software Foundation; either version 2 of the License, or
  15  * (at your option) any later version.
  16  */
  17
  18 #include <linux/init.h>
  19 #include <linux/module.h>
  20 #include <linux/errno.h>
  21 #include <asm/byteorder.h>
  22 #include <linux/crypto.h>
  23 #include <linux/types.h>
  24
  25 /* Key is padded to the maximum of 256 bits before round key generation.
  26  * Any key length <= 256 bits (32 bytes) is allowed by the algorithm.
  27  */
  28
  29 #define SERPENT_MIN_KEY_SIZE              0
  30 #define SERPENT_MAX_KEY_SIZE             32
  31 #define SERPENT_EXPKEY_WORDS            132
  32 #define SERPENT_BLOCK_SIZE               16
  33
  34 #define PHI 0x9e3779b9UL
  35
  36 #define keyiter(a,b,c,d,i,j) \
  37         b ^= d; b ^= c; b ^= a; b ^= PHI ^ i; b = rol32(b,11); k[j] = b;
  38
  39 #define loadkeys(x0,x1,x2,x3,i) \
  40         x0=k[i]; x1=k[i+1]; x2=k[i+2]; x3=k[i+3];
  41
  42 #define storekeys(x0,x1,x2,x3,i) \
  43         k[i]=x0; k[i+1]=x1; k[i+2]=x2; k[i+3]=x3;
  44
  45 #define K(x0,x1,x2,x3,i)                                \
  46         x3 ^= k[4*(i)+3];        x2 ^= k[4*(i)+2];      \
  47         x1 ^= k[4*(i)+1];        x0 ^= k[4*(i)+0];
  48
  49 #define LK(x0,x1,x2,x3,x4,i)                            \
  50                                         x0=rol32(x0,13);\
  51         x2=rol32(x2,3); x1 ^= x0;       x4  = x0 << 3;  \
  52         x3 ^= x2;       x1 ^= x2;                       \
  53         x1=rol32(x1,1); x3 ^= x4;                       \
  54         x3=rol32(x3,7); x4  = x1;                       \
  55         x0 ^= x1;       x4 <<= 7;       x2 ^= x3;       \
  56         x0 ^= x3;       x2 ^= x4;       x3 ^= k[4*i+3]; \
  57         x1 ^= k[4*i+1]; x0=rol32(x0,5); x2=rol32(x2,22);\
  58         x0 ^= k[4*i+0]; x2 ^= k[4*i+2];
  59
  60 #define KL(x0,x1,x2,x3,x4,i)                            \
  61         x0 ^= k[4*i+0]; x1 ^= k[4*i+1]; x2 ^= k[4*i+2]; \
  62         x3 ^= k[4*i+3]; x0=ror32(x0,5); x2=ror32(x2,22);\
  63         x4 =  x1;       x2 ^= x3;       x0 ^= x3;       \
  64         x4 <<= 7;       x0 ^= x1;       x1=ror32(x1,1); \
  65         x2 ^= x4;       x3=ror32(x3,7); x4 = x0 << 3;   \
  66         x1 ^= x0;       x3 ^= x4;       x0=ror32(x0,13);\
  67         x1 ^= x2;       x3 ^= x2;       x2=ror32(x2,3);
  68
  69 #define S0(x0,x1,x2,x3,x4)                              \
  70                                         x4  = x3;       \
  71         x3 |= x0;       x0 ^= x4;       x4 ^= x2;       \
  72         x4 =~ x4;       x3 ^= x1;       x1 &= x0;       \
  73         x1 ^= x4;       x2 ^= x0;       x0 ^= x3;       \
  74         x4 |= x0;       x0 ^= x2;       x2 &= x1;       \
  75         x3 ^= x2;       x1 =~ x1;       x2 ^= x4;       \
  76         x1 ^= x2;
  77
  78 #define S1(x0,x1,x2,x3,x4)                              \
  79                                         x4  = x1;       \
  80         x1 ^= x0;       x0 ^= x3;       x3 =~ x3;       \
  81         x4 &= x1;       x0 |= x1;       x3 ^= x2;       \
  82         x0 ^= x3;       x1 ^= x3;       x3 ^= x4;       \
  83         x1 |= x4;       x4 ^= x2;       x2 &= x0;       \
  84         x2 ^= x1;       x1 |= x0;       x0 =~ x0;       \
  85         x0 ^= x2;       x4 ^= x1;
  86
  87 #define S2(x0,x1,x2,x3,x4)                              \
  88                                         x3 =~ x3;       \
  89         x1 ^= x0;       x4  = x0;       x0 &= x2;       \
  90         x0 ^= x3;       x3 |= x4;       x2 ^= x1;       \
  91         x3 ^= x1;       x1 &= x0;       x0 ^= x2;       \
  92         x2 &= x3;       x3 |= x1;       x0 =~ x0;       \
  93         x3 ^= x0;       x4 ^= x0;       x0 ^= x2;       \
  94         x1 |= x2;
  95
  96 #define S3(x0,x1,x2,x3,x4)                              \
  97                                         x4  = x1;       \
  98         x1 ^= x3;       x3 |= x0;       x4 &= x0;       \
  99         x0 ^= x2;       x2 ^= x1;       x1 &= x3;       \
 100         x2 ^= x3;       x0 |= x4;       x4 ^= x3;       \
 101         x1 ^= x0;       x0 &= x3;       x3 &= x4;       \
 102         x3 ^= x2;       x4 |= x1;       x2 &= x1;       \
 103         x4 ^= x3;       x0 ^= x3;       x3 ^= x2;
 104
 105 #define S4(x0,x1,x2,x3,x4)                              \
 106                                         x4  = x3;       \
 107         x3 &= x0;       x0 ^= x4;                       \
 108         x3 ^= x2;       x2 |= x4;       x0 ^= x1;       \
 109         x4 ^= x3;       x2 |= x0;                       \
 110         x2 ^= x1;       x1 &= x0;                       \
 111         x1 ^= x4;       x4 &= x2;       x2 ^= x3;       \
 112         x4 ^= x0;       x3 |= x1;       x1 =~ x1;       \
 113         x3 ^= x0;
 114
 115 #define S5(x0,x1,x2,x3,x4)                              \
 116         x4  = x1;       x1 |= x0;                       \
 117         x2 ^= x1;       x3 =~ x3;       x4 ^= x0;       \
 118         x0 ^= x2;       x1 &= x4;       x4 |= x3;       \
 119         x4 ^= x0;       x0 &= x3;       x1 ^= x3;       \
 120         x3 ^= x2;       x0 ^= x1;       x2 &= x4;       \
 121         x1 ^= x2;       x2 &= x0;                       \
 122         x3 ^= x2;
 123
 124 #define S6(x0,x1,x2,x3,x4)                              \
 125                                         x4  = x1;       \
 126         x3 ^= x0;       x1 ^= x2;       x2 ^= x0;       \
 127         x0 &= x3;       x1 |= x3;       x4 =~ x4;       \
 128         x0 ^= x1;       x1 ^= x2;                       \
 129         x3 ^= x4;       x4 ^= x0;       x2 &= x0;       \
 130         x4 ^= x1;       x2 ^= x3;       x3 &= x1;       \
 131         x3 ^= x0;       x1 ^= x2;
 132
 133 #define S7(x0,x1,x2,x3,x4)                              \
 134                                         x1 =~ x1;       \
 135         x4  = x1;       x0 =~ x0;       x1 &= x2;       \
 136         x1 ^= x3;       x3 |= x4;       x4 ^= x2;       \
 137         x2 ^= x3;       x3 ^= x0;       x0 |= x1;       \
 138         x2 &= x0;       x0 ^= x4;       x4 ^= x3;       \
 139         x3 &= x0;       x4 ^= x1;                       \
 140         x2 ^= x4;       x3 ^= x1;       x4 |= x0;       \
 141         x4 ^= x1;
 142
 143 #define SI0(x0,x1,x2,x3,x4)                             \
 144                         x4  = x3;       x1 ^= x0;       \
 145         x3 |= x1;       x4 ^= x1;       x0 =~ x0;       \
 146         x2 ^= x3;       x3 ^= x0;       x0 &= x1;       \
 147         x0 ^= x2;       x2 &= x3;       x3 ^= x4;       \
 148         x2 ^= x3;       x1 ^= x3;       x3 &= x0;       \
 149         x1 ^= x0;       x0 ^= x2;       x4 ^= x3;
 150
 151 #define SI1(x0,x1,x2,x3,x4)                             \
 152         x1 ^= x3;       x4  = x0;                       \
 153         x0 ^= x2;       x2 =~ x2;       x4 |= x1;       \
 154         x4 ^= x3;       x3 &= x1;       x1 ^= x2;       \
 155         x2 &= x4;       x4 ^= x1;       x1 |= x3;       \
 156         x3 ^= x0;       x2 ^= x0;       x0 |= x4;       \
 157         x2 ^= x4;       x1 ^= x0;                       \
 158         x4 ^= x1;
 159
 160 #define SI2(x0,x1,x2,x3,x4)                             \
 161         x2 ^= x1;       x4  = x3;       x3 =~ x3;       \
 162         x3 |= x2;       x2 ^= x4;       x4 ^= x0;       \
 163         x3 ^= x1;       x1 |= x2;       x2 ^= x0;       \
 164         x1 ^= x4;       x4 |= x3;       x2 ^= x3;       \
 165         x4 ^= x2;       x2 &= x1;                       \
 166         x2 ^= x3;       x3 ^= x4;       x4 ^= x0;
 167
 168 #define SI3(x0,x1,x2,x3,x4)                             \
 169                                         x2 ^= x1;       \
 170         x4  = x1;       x1 &= x2;                       \
 171         x1 ^= x0;       x0 |= x4;       x4 ^= x3;       \
 172         x0 ^= x3;       x3 |= x1;       x1 ^= x2;       \
 173         x1 ^= x3;       x0 ^= x2;       x2 ^= x3;       \
 174         x3 &= x1;       x1 ^= x0;       x0 &= x2;       \
 175         x4 ^= x3;       x3 ^= x0;       x0 ^= x1;
 176
 177 #define SI4(x0,x1,x2,x3,x4)                             \
 178         x2 ^= x3;       x4  = x0;       x0 &= x1;       \
 179         x0 ^= x2;       x2 |= x3;       x4 =~ x4;       \
 180         x1 ^= x0;       x0 ^= x2;       x2 &= x4;       \
 181         x2 ^= x0;       x0 |= x4;                       \
 182         x0 ^= x3;       x3 &= x2;                       \
 183         x4 ^= x3;       x3 ^= x1;       x1 &= x0;       \
 184         x4 ^= x1;       x0 ^= x3;
 185
 186 #define SI5(x0,x1,x2,x3,x4)                             \
 187                         x4  = x1;       x1 |= x2;       \
 188         x2 ^= x4;       x1 ^= x3;       x3 &= x4;       \
 189         x2 ^= x3;       x3 |= x0;       x0 =~ x0;       \
 190         x3 ^= x2;       x2 |= x0;       x4 ^= x1;       \
 191         x2 ^= x4;       x4 &= x0;       x0 ^= x1;       \
 192         x1 ^= x3;       x0 &= x2;       x2 ^= x3;       \
 193         x0 ^= x2;       x2 ^= x4;       x4 ^= x3;
 194
 195 #define SI6(x0,x1,x2,x3,x4)                             \
 196                         x0 ^= x2;                       \
 197         x4  = x0;       x0 &= x3;       x2 ^= x3;       \
 198         x0 ^= x2;       x3 ^= x1;       x2 |= x4;       \
 199         x2 ^= x3;       x3 &= x0;       x0 =~ x0;       \
 200         x3 ^= x1;       x1 &= x2;       x4 ^= x0;       \
 201         x3 ^= x4;       x4 ^= x2;       x0 ^= x1;       \
 202         x2 ^= x0;
 203
 204 #define SI7(x0,x1,x2,x3,x4)                             \
 205         x4  = x3;       x3 &= x0;       x0 ^= x2;       \
 206         x2 |= x4;       x4 ^= x1;       x0 =~ x0;       \
 207         x1 |= x3;       x4 ^= x0;       x0 &= x2;       \
 208         x0 ^= x1;       x1 &= x2;       x3 ^= x2;       \
 209         x4 ^= x3;       x2 &= x3;       x3 |= x0;       \
 210         x1 ^= x4;       x3 ^= x4;       x4 &= x0;       \
 211         x4 ^= x2;
 212
 213 struct serpent_ctx {
 214         u32 expkey[SERPENT_EXPKEY_WORDS];
 215 };
 216
 217
 218 static int serpent_setkey(void *ctx, const u8 *key, unsigned int keylen, u32 *flags)
 219 {
 220         u32 *k = ((struct serpent_ctx *)ctx)->expkey;
 221         u8  *k8 = (u8 *)k;
 222         u32 r0,r1,r2,r3,r4;
 223         int i;
 224
 225         if ((keylen < SERPENT_MIN_KEY_SIZE)
 226                         || (keylen > SERPENT_MAX_KEY_SIZE))
 227         {
 228                 *flags |= CRYPTO_TFM_RES_BAD_KEY_LEN;
 229                 return -EINVAL;
 230         }
 231
 232         /* Copy key, add padding */
 233
 234         for (i = 0; i < keylen; ++i)
 235                 k8[i] = key[i];
 236         if (i < SERPENT_MAX_KEY_SIZE)
 237                 k8[i++] = 1;
 238         while (i < SERPENT_MAX_KEY_SIZE)
 239                 k8[i++] = 0;
 240
 241         /* Expand key using polynomial */
 242
 243         r0 = le32_to_cpu(k[3]);
 244         r1 = le32_to_cpu(k[4]);
 245         r2 = le32_to_cpu(k[5]);
 246         r3 = le32_to_cpu(k[6]);
 247         r4 = le32_to_cpu(k[7]);
 248
 249         keyiter(le32_to_cpu(k[0]),r0,r4,r2,0,0);
 250         keyiter(le32_to_cpu(k[1]),r1,r0,r3,1,1);
 251         keyiter(le32_to_cpu(k[2]),r2,r1,r4,2,2);
 252         keyiter(le32_to_cpu(k[3]),r3,r2,r0,3,3);
 253         keyiter(le32_to_cpu(k[4]),r4,r3,r1,4,4);
 254         keyiter(le32_to_cpu(k[5]),r0,r4,r2,5,5);
 255         keyiter(le32_to_cpu(k[6]),r1,r0,r3,6,6);
 256         keyiter(le32_to_cpu(k[7]),r2,r1,r4,7,7);
 257
 258         keyiter(k[  0],r3,r2,r0,  8,  8); keyiter(k[  1],r4,r3,r1,  9,  9);
 259         keyiter(k[  2],r0,r4,r2, 10, 10); keyiter(k[  3],r1,r0,r3, 11, 11);
 260         keyiter(k[  4],r2,r1,r4, 12, 12); keyiter(k[  5],r3,r2,r0, 13, 13);
 261         keyiter(k[  6],r4,r3,r1, 14, 14); keyiter(k[  7],r0,r4,r2, 15, 15);
 262         keyiter(k[  8],r1,r0,r3, 16, 16); keyiter(k[  9],r2,r1,r4, 17, 17);
 263         keyiter(k[ 10],r3,r2,r0, 18, 18); keyiter(k[ 11],r4,r3,r1, 19, 19);
 264         keyiter(k[ 12],r0,r4,r2, 20, 20); keyiter(k[ 13],r1,r0,r3, 21, 21);
 265         keyiter(k[ 14],r2,r1,r4, 22, 22); keyiter(k[ 15],r3,r2,r0, 23, 23);
 266         keyiter(k[ 16],r4,r3,r1, 24, 24); keyiter(k[ 17],r0,r4,r2, 25, 25);
 267         keyiter(k[ 18],r1,r0,r3, 26, 26); keyiter(k[ 19],r2,r1,r4, 27, 27);
 268         keyiter(k[ 20],r3,r2,r0, 28, 28); keyiter(k[ 21],r4,r3,r1, 29, 29);
 269         keyiter(k[ 22],r0,r4,r2, 30, 30); keyiter(k[ 23],r1,r0,r3, 31, 31);
 270
 271         k += 50;
 272
 273         keyiter(k[-26],r2,r1,r4, 32,-18); keyiter(k[-25],r3,r2,r0, 33,-17);
 274         keyiter(k[-24],r4,r3,r1, 34,-16); keyiter(k[-23],r0,r4,r2, 35,-15);
 275         keyiter(k[-22],r1,r0,r3, 36,-14); keyiter(k[-21],r2,r1,r4, 37,-13);
 276         keyiter(k[-20],r3,r2,r0, 38,-12); keyiter(k[-19],r4,r3,r1, 39,-11);
 277         keyiter(k[-18],r0,r4,r2, 40,-10); keyiter(k[-17],r1,r0,r3, 41, -9);
 278         keyiter(k[-16],r2,r1,r4, 42, -8); keyiter(k[-15],r3,r2,r0, 43, -7);
 279         keyiter(k[-14],r4,r3,r1, 44, -6); keyiter(k[-13],r0,r4,r2, 45, -5);
 280         keyiter(k[-12],r1,r0,r3, 46, -4); keyiter(k[-11],r2,r1,r4, 47, -3);
 281         keyiter(k[-10],r3,r2,r0, 48, -2); keyiter(k[ -9],r4,r3,r1, 49, -1);
 282         keyiter(k[ -8],r0,r4,r2, 50,  0); keyiter(k[ -7],r1,r0,r3, 51,  1);
 283         keyiter(k[ -6],r2,r1,r4, 52,  2); keyiter(k[ -5],r3,r2,r0, 53,  3);
 284         keyiter(k[ -4],r4,r3,r1, 54,  4); keyiter(k[ -3],r0,r4,r2, 55,  5);
 285         keyiter(k[ -2],r1,r0,r3, 56,  6); keyiter(k[ -1],r2,r1,r4, 57,  7);
 286         keyiter(k[  0],r3,r2,r0, 58,  8); keyiter(k[  1],r4,r3,r1, 59,  9);
 287         keyiter(k[  2],r0,r4,r2, 60, 10); keyiter(k[  3],r1,r0,r3, 61, 11);
 288         keyiter(k[  4],r2,r1,r4, 62, 12); keyiter(k[  5],r3,r2,r0, 63, 13);
 289         keyiter(k[  6],r4,r3,r1, 64, 14); keyiter(k[  7],r0,r4,r2, 65, 15);
 290         keyiter(k[  8],r1,r0,r3, 66, 16); keyiter(k[  9],r2,r1,r4, 67, 17);
 291         keyiter(k[ 10],r3,r2,r0, 68, 18); keyiter(k[ 11],r4,r3,r1, 69, 19);
 292         keyiter(k[ 12],r0,r4,r2, 70, 20); keyiter(k[ 13],r1,r0,r3, 71, 21);
 293         keyiter(k[ 14],r2,r1,r4, 72, 22); keyiter(k[ 15],r3,r2,r0, 73, 23);
 294         keyiter(k[ 16],r4,r3,r1, 74, 24); keyiter(k[ 17],r0,r4,r2, 75, 25);
 295         keyiter(k[ 18],r1,r0,r3, 76, 26); keyiter(k[ 19],r2,r1,r4, 77, 27);
 296         keyiter(k[ 20],r3,r2,r0, 78, 28); keyiter(k[ 21],r4,r3,r1, 79, 29);
 297         keyiter(k[ 22],r0,r4,r2, 80, 30); keyiter(k[ 23],r1,r0,r3, 81, 31);
 298
 299         k += 50;
 300
 301         keyiter(k[-26],r2,r1,r4, 82,-18); keyiter(k[-25],r3,r2,r0, 83,-17);
 302         keyiter(k[-24],r4,r3,r1, 84,-16); keyiter(k[-23],r0,r4,r2, 85,-15);
 303         keyiter(k[-22],r1,r0,r3, 86,-14); keyiter(k[-21],r2,r1,r4, 87,-13);
 304         keyiter(k[-20],r3,r2,r0, 88,-12); keyiter(k[-19],r4,r3,r1, 89,-11);
 305         keyiter(k[-18],r0,r4,r2, 90,-10); keyiter(k[-17],r1,r0,r3, 91, -9);
 306         keyiter(k[-16],r2,r1,r4, 92, -8); keyiter(k[-15],r3,r2,r0, 93, -7);
 307         keyiter(k[-14],r4,r3,r1, 94, -6); keyiter(k[-13],r0,r4,r2, 95, -5);
 308         keyiter(k[-12],r1,r0,r3, 96, -4); keyiter(k[-11],r2,r1,r4, 97, -3);
 309         keyiter(k[-10],r3,r2,r0, 98, -2); keyiter(k[ -9],r4,r3,r1, 99, -1);
 310         keyiter(k[ -8],r0,r4,r2,100,  0); keyiter(k[ -7],r1,r0,r3,101,  1);
 311         keyiter(k[ -6],r2,r1,r4,102,  2); keyiter(k[ -5],r3,r2,r0,103,  3);
 312         keyiter(k[ -4],r4,r3,r1,104,  4); keyiter(k[ -3],r0,r4,r2,105,  5);
 313         keyiter(k[ -2],r1,r0,r3,106,  6); keyiter(k[ -1],r2,r1,r4,107,  7);
 314         keyiter(k[  0],r3,r2,r0,108,  8); keyiter(k[  1],r4,r3,r1,109,  9);
 315         keyiter(k[  2],r0,r4,r2,110, 10); keyiter(k[  3],r1,r0,r3,111, 11);
 316         keyiter(k[  4],r2,r1,r4,112, 12); keyiter(k[  5],r3,r2,r0,113, 13);
 317         keyiter(k[  6],r4,r3,r1,114, 14); keyiter(k[  7],r0,r4,r2,115, 15);
 318         keyiter(k[  8],r1,r0,r3,116, 16); keyiter(k[  9],r2,r1,r4,117, 17);
 319         keyiter(k[ 10],r3,r2,r0,118, 18); keyiter(k[ 11],r4,r3,r1,119, 19);
 320         keyiter(k[ 12],r0,r4,r2,120, 20); keyiter(k[ 13],r1,r0,r3,121, 21);
 321         keyiter(k[ 14],r2,r1,r4,122, 22); keyiter(k[ 15],r3,r2,r0,123, 23);
 322         keyiter(k[ 16],r4,r3,r1,124, 24); keyiter(k[ 17],r0,r4,r2,125, 25);
 323         keyiter(k[ 18],r1,r0,r3,126, 26); keyiter(k[ 19],r2,r1,r4,127, 27);
 324         keyiter(k[ 20],r3,r2,r0,128, 28); keyiter(k[ 21],r4,r3,r1,129, 29);
 325         keyiter(k[ 22],r0,r4,r2,130, 30); keyiter(k[ 23],r1,r0,r3,131, 31);
 326
 327         /* Apply S-boxes */
 328
 329         S3(r3,r4,r0,r1,r2); storekeys(r1,r2,r4,r3, 28); loadkeys(r1,r2,r4,r3, 24);
 330         S4(r1,r2,r4,r3,r0); storekeys(r2,r4,r3,r0, 24); loadkeys(r2,r4,r3,r0, 20);
 331         S5(r2,r4,r3,r0,r1); storekeys(r1,r2,r4,r0, 20); loadkeys(r1,r2,r4,r0, 16);
 332         S6(r1,r2,r4,r0,r3); storekeys(r4,r3,r2,r0, 16); loadkeys(r4,r3,r2,r0, 12);
 333         S7(r4,r3,r2,r0,r1); storekeys(r1,r2,r0,r4, 12); loadkeys(r1,r2,r0,r4,  8);
 334         S0(r1,r2,r0,r4,r3); storekeys(r0,r2,r4,r1,  8); loadkeys(r0,r2,r4,r1,  4);
 335         S1(r0,r2,r4,r1,r3); storekeys(r3,r4,r1,r0,  4); loadkeys(r3,r4,r1,r0,  0);
 336         S2(r3,r4,r1,r0,r2); storekeys(r2,r4,r3,r0,  0); loadkeys(r2,r4,r3,r0, -4);
 337         S3(r2,r4,r3,r0,r1); storekeys(r0,r1,r4,r2, -4); loadkeys(r0,r1,r4,r2, -8);
 338         S4(r0,r1,r4,r2,r3); storekeys(r1,r4,r2,r3, -8); loadkeys(r1,r4,r2,r3,-12);
 339         S5(r1,r4,r2,r3,r0); storekeys(r0,r1,r4,r3,-12); loadkeys(r0,r1,r4,r3,-16);
 340         S6(r0,r1,r4,r3,r2); storekeys(r4,r2,r1,r3,-16); loadkeys(r4,r2,r1,r3,-20);
 341         S7(r4,r2,r1,r3,r0); storekeys(r0,r1,r3,r4,-20); loadkeys(r0,r1,r3,r4,-24);
 342         S0(r0,r1,r3,r4,r2); storekeys(r3,r1,r4,r0,-24); loadkeys(r3,r1,r4,r0,-28);
 343         k -= 50;
 344         S1(r3,r1,r4,r0,r2); storekeys(r2,r4,r0,r3, 22); loadkeys(r2,r4,r0,r3, 18);
 345         S2(r2,r4,r0,r3,r1); storekeys(r1,r4,r2,r3, 18); loadkeys(r1,r4,r2,r3, 14);
 346         S3(r1,r4,r2,r3,r0); storekeys(r3,r0,r4,r1, 14); loadkeys(r3,r0,r4,r1, 10);
 347         S4(r3,r0,r4,r1,r2); storekeys(r0,r4,r1,r2, 10); loadkeys(r0,r4,r1,r2,  6);
 348         S5(r0,r4,r1,r2,r3); storekeys(r3,r0,r4,r2,  6); loadkeys(r3,r0,r4,r2,  2);
 349         S6(r3,r0,r4,r2,r1); storekeys(r4,r1,r0,r2,  2); loadkeys(r4,r1,r0,r2, -2);
 350         S7(r4,r1,r0,r2,r3); storekeys(r3,r0,r2,r4, -2); loadkeys(r3,r0,r2,r4, -6);
 351         S0(r3,r0,r2,r4,r1); storekeys(r2,r0,r4,r3, -6); loadkeys(r2,r0,r4,r3,-10);
 352         S1(r2,r0,r4,r3,r1); storekeys(r1,r4,r3,r2,-10); loadkeys(r1,r4,r3,r2,-14);
 353         S2(r1,r4,r3,r2,r0); storekeys(r0,r4,r1,r2,-14); loadkeys(r0,r4,r1,r2,-18);
 354         S3(r0,r4,r1,r2,r3); storekeys(r2,r3,r4,r0,-18); loadkeys(r2,r3,r4,r0,-22);
 355         k -= 50;
 356         S4(r2,r3,r4,r0,r1); storekeys(r3,r4,r0,r1, 28); loadkeys(r3,r4,r0,r1, 24);
 357         S5(r3,r4,r0,r1,r2); storekeys(r2,r3,r4,r1, 24); loadkeys(r2,r3,r4,r1, 20);
 358         S6(r2,r3,r4,r1,r0); storekeys(r4,r0,r3,r1, 20); loadkeys(r4,r0,r3,r1, 16);
 359         S7(r4,r0,r3,r1,r2); storekeys(r2,r3,r1,r4, 16); loadkeys(r2,r3,r1,r4, 12);
 360         S0(r2,r3,r1,r4,r0); storekeys(r1,r3,r4,r2, 12); loadkeys(r1,r3,r4,r2,  8);
 361         S1(r1,r3,r4,r2,r0); storekeys(r0,r4,r2,r1,  8); loadkeys(r0,r4,r2,r1,  4);
 362         S2(r0,r4,r2,r1,r3); storekeys(r3,r4,r0,r1,  4); loadkeys(r3,r4,r0,r1,  0);
 363         S3(r3,r4,r0,r1,r2); storekeys(r1,r2,r4,r3,  0);
 364
 365         return 0;
 366 }
 367
 368 static void serpent_encrypt(void *ctx, u8 *dst, const u8 *src)
 369 {
 370         const u32
 371                 *k = ((struct serpent_ctx *)ctx)->expkey,
 372                 *s = (const u32 *)src;
 373         u32     *d = (u32 *)dst,
 374                 r0, r1, r2, r3, r4;
 375
 376 /*
 377  * Note: The conversions between u8* and u32* might cause trouble
 378  * on architectures with stricter alignment rules than x86
 379  */
 380
 381         r0 = le32_to_cpu(s[0]);
 382         r1 = le32_to_cpu(s[1]);
 383         r2 = le32_to_cpu(s[2]);
 384         r3 = le32_to_cpu(s[3]);
 385
 386                                  K(r0,r1,r2,r3,0);
 387         S0(r0,r1,r2,r3,r4);     LK(r2,r1,r3,r0,r4,1);
 388         S1(r2,r1,r3,r0,r4);     LK(r4,r3,r0,r2,r1,2);
 389         S2(r4,r3,r0,r2,r1);     LK(r1,r3,r4,r2,r0,3);
 390         S3(r1,r3,r4,r2,r0);     LK(r2,r0,r3,r1,r4,4);
 391         S4(r2,r0,r3,r1,r4);     LK(r0,r3,r1,r4,r2,5);
 392         S5(r0,r3,r1,r4,r2);     LK(r2,r0,r3,r4,r1,6);
 393         S6(r2,r0,r3,r4,r1);     LK(r3,r1,r0,r4,r2,7);
 394         S7(r3,r1,r0,r4,r2);     LK(r2,r0,r4,r3,r1,8);
 395         S0(r2,r0,r4,r3,r1);     LK(r4,r0,r3,r2,r1,9);
 396         S1(r4,r0,r3,r2,r1);     LK(r1,r3,r2,r4,r0,10);
 397         S2(r1,r3,r2,r4,r0);     LK(r0,r3,r1,r4,r2,11);
 398         S3(r0,r3,r1,r4,r2);     LK(r4,r2,r3,r0,r1,12);
 399         S4(r4,r2,r3,r0,r1);     LK(r2,r3,r0,r1,r4,13);
 400         S5(r2,r3,r0,r1,r4);     LK(r4,r2,r3,r1,r0,14);
 401         S6(r4,r2,r3,r1,r0);     LK(r3,r0,r2,r1,r4,15);
 402         S7(r3,r0,r2,r1,r4);     LK(r4,r2,r1,r3,r0,16);
 403         S0(r4,r2,r1,r3,r0);     LK(r1,r2,r3,r4,r0,17);
 404         S1(r1,r2,r3,r4,r0);     LK(r0,r3,r4,r1,r2,18);
 405         S2(r0,r3,r4,r1,r2);     LK(r2,r3,r0,r1,r4,19);
 406         S3(r2,r3,r0,r1,r4);     LK(r1,r4,r3,r2,r0,20);
 407         S4(r1,r4,r3,r2,r0);     LK(r4,r3,r2,r0,r1,21);
 408         S5(r4,r3,r2,r0,r1);     LK(r1,r4,r3,r0,r2,22);
 409         S6(r1,r4,r3,r0,r2);     LK(r3,r2,r4,r0,r1,23);
 410         S7(r3,r2,r4,r0,r1);     LK(r1,r4,r0,r3,r2,24);
 411         S0(r1,r4,r0,r3,r2);     LK(r0,r4,r3,r1,r2,25);
 412         S1(r0,r4,r3,r1,r2);     LK(r2,r3,r1,r0,r4,26);
 413         S2(r2,r3,r1,r0,r4);     LK(r4,r3,r2,r0,r1,27);
 414         S3(r4,r3,r2,r0,r1);     LK(r0,r1,r3,r4,r2,28);
 415         S4(r0,r1,r3,r4,r2);     LK(r1,r3,r4,r2,r0,29);
 416         S5(r1,r3,r4,r2,r0);     LK(r0,r1,r3,r2,r4,30);
 417         S6(r0,r1,r3,r2,r4);     LK(r3,r4,r1,r2,r0,31);
 418         S7(r3,r4,r1,r2,r0);      K(r0,r1,r2,r3,32);
 419
 420         d[0] = cpu_to_le32(r0);
 421         d[1] = cpu_to_le32(r1);
 422         d[2] = cpu_to_le32(r2);
 423         d[3] = cpu_to_le32(r3);
 424 }
 425
 426 static void serpent_decrypt(void *ctx, u8 *dst, const u8 *src)
 427 {
 428         const u32
 429                 *k = ((struct serpent_ctx *)ctx)->expkey,
 430                 *s = (const u32 *)src;
 431         u32     *d = (u32 *)dst,
 432                 r0, r1, r2, r3, r4;
 433
 434         r0 = le32_to_cpu(s[0]);
 435         r1 = le32_to_cpu(s[1]);
 436         r2 = le32_to_cpu(s[2]);
 437         r3 = le32_to_cpu(s[3]);
 438
 439                                 K(r0,r1,r2,r3,32);
 440         SI7(r0,r1,r2,r3,r4);    KL(r1,r3,r0,r4,r2,31);
 441         SI6(r1,r3,r0,r4,r2);    KL(r0,r2,r4,r1,r3,30);
 442         SI5(r0,r2,r4,r1,r3);    KL(r2,r3,r0,r4,r1,29);
 443         SI4(r2,r3,r0,r4,r1);    KL(r2,r0,r1,r4,r3,28);
 444         SI3(r2,r0,r1,r4,r3);    KL(r1,r2,r3,r4,r0,27);
 445         SI2(r1,r2,r3,r4,r0);    KL(r2,r0,r4,r3,r1,26);
 446         SI1(r2,r0,r4,r3,r1);    KL(r1,r0,r4,r3,r2,25);
 447         SI0(r1,r0,r4,r3,r2);    KL(r4,r2,r0,r1,r3,24);
 448         SI7(r4,r2,r0,r1,r3);    KL(r2,r1,r4,r3,r0,23);
 449         SI6(r2,r1,r4,r3,r0);    KL(r4,r0,r3,r2,r1,22);
 450         SI5(r4,r0,r3,r2,r1);    KL(r0,r1,r4,r3,r2,21);
 451         SI4(r0,r1,r4,r3,r2);    KL(r0,r4,r2,r3,r1,20);
 452         SI3(r0,r4,r2,r3,r1);    KL(r2,r0,r1,r3,r4,19);
 453         SI2(r2,r0,r1,r3,r4);    KL(r0,r4,r3,r1,r2,18);
 454         SI1(r0,r4,r3,r1,r2);    KL(r2,r4,r3,r1,r0,17);
 455         SI0(r2,r4,r3,r1,r0);    KL(r3,r0,r4,r2,r1,16);
 456         SI7(r3,r0,r4,r2,r1);    KL(r0,r2,r3,r1,r4,15);
 457         SI6(r0,r2,r3,r1,r4);    KL(r3,r4,r1,r0,r2,14);
 458         SI5(r3,r4,r1,r0,r2);    KL(r4,r2,r3,r1,r0,13);
 459         SI4(r4,r2,r3,r1,r0);    KL(r4,r3,r0,r1,r2,12);
 460         SI3(r4,r3,r0,r1,r2);    KL(r0,r4,r2,r1,r3,11);
 461         SI2(r0,r4,r2,r1,r3);    KL(r4,r3,r1,r2,r0,10);
 462         SI1(r4,r3,r1,r2,r0);    KL(r0,r3,r1,r2,r4,9);
 463         SI0(r0,r3,r1,r2,r4);    KL(r1,r4,r3,r0,r2,8);
 464         SI7(r1,r4,r3,r0,r2);    KL(r4,r0,r1,r2,r3,7);
 465         SI6(r4,r0,r1,r2,r3);    KL(r1,r3,r2,r4,r0,6);
 466         SI5(r1,r3,r2,r4,r0);    KL(r3,r0,r1,r2,r4,5);
 467         SI4(r3,r0,r1,r2,r4);    KL(r3,r1,r4,r2,r0,4);
 468         SI3(r3,r1,r4,r2,r0);    KL(r4,r3,r0,r2,r1,3);
 469         SI2(r4,r3,r0,r2,r1);    KL(r3,r1,r2,r0,r4,2);
 470         SI1(r3,r1,r2,r0,r4);    KL(r4,r1,r2,r0,r3,1);
 471         SI0(r4,r1,r2,r0,r3);    K(r2,r3,r1,r4,0);
 472
 473         d[0] = cpu_to_le32(r2);
 474         d[1] = cpu_to_le32(r3);
 475         d[2] = cpu_to_le32(r1);
 476         d[3] = cpu_to_le32(r4);
 477 }
 478
 479 static struct crypto_alg serpent_alg = {
 480         .cra_name               =       "serpent",
 481         .cra_flags              =       CRYPTO_ALG_TYPE_CIPHER,
 482         .cra_blocksize          =       SERPENT_BLOCK_SIZE,
 483         .cra_ctxsize            =       sizeof(struct serpent_ctx),
 484         .cra_module             =       THIS_MODULE,
 485         .cra_list               =       LIST_HEAD_INIT(serpent_alg.cra_list),
 486         .cra_u                  =       { .cipher = {
 487         .cia_min_keysize        =       SERPENT_MIN_KEY_SIZE,
 488         .cia_max_keysize        =       SERPENT_MAX_KEY_SIZE,
 489         .cia_setkey             =       serpent_setkey,
 490         .cia_encrypt            =       serpent_encrypt,
 491         .cia_decrypt            =       serpent_decrypt } }
 492 };
 493
 494 static int tnepres_setkey(void *ctx, const u8 *key, unsigned int keylen, u32 *flags)
 495 {
 496         u8 rev_key[SERPENT_MAX_KEY_SIZE];
 497         int i;
 498
 499         if ((keylen < SERPENT_MIN_KEY_SIZE)
 500             || (keylen > SERPENT_MAX_KEY_SIZE)) {
 501                 *flags |= CRYPTO_TFM_RES_BAD_KEY_LEN;
 502                 return -EINVAL;
 503         }
 504
 505         for (i = 0; i < keylen; ++i)
 506                 rev_key[keylen - i - 1] = key[i];
 507
 508         return serpent_setkey(ctx, rev_key, keylen, flags);
 509 }
 510
 511 static void tnepres_encrypt(void *ctx, u8 *dst, const u8 *src)
 512 {
 513         const u32 * const s = (const u32 * const)src;
 514         u32 * const d = (u32 * const)dst;
 515
 516         u32 rs[4], rd[4];
 517
 518         rs[0] = swab32(s[3]);
 519         rs[1] = swab32(s[2]);
 520         rs[2] = swab32(s[1]);
 521         rs[3] = swab32(s[0]);
 522
 523         serpent_encrypt(ctx, (u8 *)rd, (u8 *)rs);
 524
 525         d[0] = swab32(rd[3]);
 526         d[1] = swab32(rd[2]);
 527         d[2] = swab32(rd[1]);
 528         d[3] = swab32(rd[0]);
 529 }
 530
 531 static void tnepres_decrypt(void *ctx, u8 *dst, const u8 *src)
 532 {
 533         const u32 * const s = (const u32 * const)src;
 534         u32 * const d = (u32 * const)dst;
 535
 536         u32 rs[4], rd[4];
 537
 538         rs[0] = swab32(s[3]);
 539         rs[1] = swab32(s[2]);
 540         rs[2] = swab32(s[1]);
 541         rs[3] = swab32(s[0]);
 542
 543         serpent_decrypt(ctx, (u8 *)rd, (u8 *)rs);
 544
 545         d[0] = swab32(rd[3]);
 546         d[1] = swab32(rd[2]);
 547         d[2] = swab32(rd[1]);
 548         d[3] = swab32(rd[0]);
 549 }
 550
 551 static struct crypto_alg tnepres_alg = {
 552         .cra_name               =       "tnepres",
 553         .cra_flags              =       CRYPTO_ALG_TYPE_CIPHER,
 554         .cra_blocksize          =       SERPENT_BLOCK_SIZE,
 555         .cra_ctxsize            =       sizeof(struct serpent_ctx),
 556         .cra_alignmask          =       3,
 557         .cra_module             =       THIS_MODULE,
 558         .cra_list               =       LIST_HEAD_INIT(serpent_alg.cra_list),
 559         .cra_u                  =       { .cipher = {
 560         .cia_min_keysize        =       SERPENT_MIN_KEY_SIZE,
 561         .cia_max_keysize        =       SERPENT_MAX_KEY_SIZE,
 562         .cia_setkey             =       tnepres_setkey,
 563         .cia_encrypt            =       tnepres_encrypt,
 564         .cia_decrypt            =       tnepres_decrypt } }
 565 };
 566
 567 static int __init init(void)
 568 {
 569         int ret = crypto_register_alg(&serpent_alg);
 570
 571         if (ret)
 572                 return ret;
 573
 574         ret = crypto_register_alg(&tnepres_alg);
 575
 576         if (ret)
 577                 crypto_unregister_alg(&serpent_alg);
 578
 579         return ret;
 580 }
 581
 582 static void __exit fini(void)
 583 {
 584         crypto_unregister_alg(&tnepres_alg);
 585         crypto_unregister_alg(&serpent_alg);
 586 }
 587
 588 module_init(init);
 589 module_exit(fini);
 590
 591 MODULE_LICENSE("GPL");
 592 MODULE_DESCRIPTION("Serpent and tnepres (kerneli compatible serpent reversed) Cipher Algorithm");
 593 MODULE_AUTHOR("Dag Arne Osvik <osvik@ii.uib.no>");
 594 MODULE_ALIAS("tnepres");