src/patches/suse-2.6.27.39/patches.suse/twofish-2.6

   1 Subject: Twofish encryption for loop device for old S.u.S.E. crypto partitions
   2 From: kraxel@suse.de
   3
   4 See $subject, used up to 9.2 on new installs.
   5
   6 ---
   7  drivers/block/Kconfig      |    6
   8  drivers/block/Makefile     |    1
   9  drivers/block/loop_fish2.c |  625 +++++++++++++++++++++++++++++++++++++++++++++
  10  3 files changed, 632 insertions(+)
  11
  12 --- a/drivers/block/Kconfig
  13 +++ b/drivers/block/Kconfig
  14 @@ -409,6 +409,12 @@ config SUNVDC
  15           Support for virtual disk devices as a client under Sun
  16           Logical Domains.
  17
  18 +config CIPHER_TWOFISH
  19 +       tristate "Twofish encryption for loop device for old S.u.S.E. crypto partitions"
  20 +       depends on BLK_DEV_LOOP
  21 +       help
  22 +         Say Y here if you want to support old S.u.S.E. crypto partitions.
  23 +
  24  source "drivers/s390/block/Kconfig"
  25
  26  config XILINX_SYSACE
  27 --- a/drivers/block/Makefile
  28 +++ b/drivers/block/Makefile
  29 @@ -32,3 +32,4 @@ obj-$(CONFIG_BLK_DEV_UB)      += ub.o
  30  obj-$(CONFIG_BLK_DEV_HD)       += hd.o
  31
  32  obj-$(CONFIG_XEN_BLKDEV_FRONTEND)      += xen-blkfront.o
  33 +obj-$(CONFIG_CIPHER_TWOFISH)   += loop_fish2.o
  34 --- /dev/null
  35 +++ b/drivers/block/loop_fish2.c
  36 @@ -0,0 +1,625 @@
  37 +#include <linux/module.h>
  38 +#include <linux/errno.h>
  39 +#include <linux/init.h>
  40 +#include <linux/fs.h>
  41 +#include <linux/string.h>
  42 +#include <linux/mm.h>
  43 +#include <linux/slab.h>
  44 +#include <asm/byteorder.h>
  45 +#include <linux/loop.h>
  46 +
  47 +#define ROL(x,c) (((x) << (c)) | ((x) >> (32-(c))))
  48 +#define ROR(x,c) (((x) >> (c)) | ((x) << (32-(c))))
  49 +#define Bswap(x) __le32_to_cpu(x)
  50 +
  51 +#define DWORD __u32
  52 +#define BYTE unsigned char
  53 +
  54 +typedef struct fish2_key
  55 +{ int keyLen;       /* Key Length in Bit */
  56 +  DWORD sboxKeys[4];
  57 +  DWORD subKeys[40];
  58 +  BYTE  key[32];
  59 +  DWORD sbox_full[1024];  /* This have to be 1024 DWORDs */
  60 +} fish2_key;
  61 +
  62 +
  63 +/* Mul_5B[i] is  0x5B * i   in GF(256), whatever that means... */
  64 +
  65 +static unsigned char Mul_5B[256] = {
  66 +    0x00,0x5B,0xB6,0xED,0x05,0x5E,0xB3,0xE8,
  67 +    0x0A,0x51,0xBC,0xE7,0x0F,0x54,0xB9,0xE2,
  68 +    0x14,0x4F,0xA2,0xF9,0x11,0x4A,0xA7,0xFC,
  69 +    0x1E,0x45,0xA8,0xF3,0x1B,0x40,0xAD,0xF6,
  70 +    0x28,0x73,0x9E,0xC5,0x2D,0x76,0x9B,0xC0,
  71 +    0x22,0x79,0x94,0xCF,0x27,0x7C,0x91,0xCA,
  72 +    0x3C,0x67,0x8A,0xD1,0x39,0x62,0x8F,0xD4,
  73 +    0x36,0x6D,0x80,0xDB,0x33,0x68,0x85,0xDE,
  74 +    0x50,0x0B,0xE6,0xBD,0x55,0x0E,0xE3,0xB8,
  75 +    0x5A,0x01,0xEC,0xB7,0x5F,0x04,0xE9,0xB2,
  76 +    0x44,0x1F,0xF2,0xA9,0x41,0x1A,0xF7,0xAC,
  77 +    0x4E,0x15,0xF8,0xA3,0x4B,0x10,0xFD,0xA6,
  78 +    0x78,0x23,0xCE,0x95,0x7D,0x26,0xCB,0x90,
  79 +    0x72,0x29,0xC4,0x9F,0x77,0x2C,0xC1,0x9A,
  80 +    0x6C,0x37,0xDA,0x81,0x69,0x32,0xDF,0x84,
  81 +    0x66,0x3D,0xD0,0x8B,0x63,0x38,0xD5,0x8E,
  82 +    0xA0,0xFB,0x16,0x4D,0xA5,0xFE,0x13,0x48,
  83 +    0xAA,0xF1,0x1C,0x47,0xAF,0xF4,0x19,0x42,
  84 +    0xB4,0xEF,0x02,0x59,0xB1,0xEA,0x07,0x5C,
  85 +    0xBE,0xE5,0x08,0x53,0xBB,0xE0,0x0D,0x56,
  86 +    0x88,0xD3,0x3E,0x65,0x8D,0xD6,0x3B,0x60,
  87 +    0x82,0xD9,0x34,0x6F,0x87,0xDC,0x31,0x6A,
  88 +    0x9C,0xC7,0x2A,0x71,0x99,0xC2,0x2F,0x74,
  89 +    0x96,0xCD,0x20,0x7B,0x93,0xC8,0x25,0x7E,
  90 +    0xF0,0xAB,0x46,0x1D,0xF5,0xAE,0x43,0x18,
  91 +    0xFA,0xA1,0x4C,0x17,0xFF,0xA4,0x49,0x12,
  92 +    0xE4,0xBF,0x52,0x09,0xE1,0xBA,0x57,0x0C,
  93 +    0xEE,0xB5,0x58,0x03,0xEB,0xB0,0x5D,0x06,
  94 +    0xD8,0x83,0x6E,0x35,0xDD,0x86,0x6B,0x30,
  95 +    0xD2,0x89,0x64,0x3F,0xD7,0x8C,0x61,0x3A,
  96 +    0xCC,0x97,0x7A,0x21,0xC9,0x92,0x7F,0x24,
  97 +    0xC6,0x9D,0x70,0x2B,0xC3,0x98,0x75,0x2E };
  98 +
  99 +
 100 +/* Mul_EF[i] is  0xEF * i   in GF(256), whatever that means... */
 101 +
 102 +static unsigned char Mul_EF[256] = {
 103 +    0x00,0xEF,0xB7,0x58,0x07,0xE8,0xB0,0x5F,
 104 +    0x0E,0xE1,0xB9,0x56,0x09,0xE6,0xBE,0x51,
 105 +    0x1C,0xF3,0xAB,0x44,0x1B,0xF4,0xAC,0x43,
 106 +    0x12,0xFD,0xA5,0x4A,0x15,0xFA,0xA2,0x4D,
 107 +    0x38,0xD7,0x8F,0x60,0x3F,0xD0,0x88,0x67,
 108 +    0x36,0xD9,0x81,0x6E,0x31,0xDE,0x86,0x69,
 109 +    0x24,0xCB,0x93,0x7C,0x23,0xCC,0x94,0x7B,
 110 +    0x2A,0xC5,0x9D,0x72,0x2D,0xC2,0x9A,0x75,
 111 +    0x70,0x9F,0xC7,0x28,0x77,0x98,0xC0,0x2F,
 112 +    0x7E,0x91,0xC9,0x26,0x79,0x96,0xCE,0x21,
 113 +    0x6C,0x83,0xDB,0x34,0x6B,0x84,0xDC,0x33,
 114 +    0x62,0x8D,0xD5,0x3A,0x65,0x8A,0xD2,0x3D,
 115 +    0x48,0xA7,0xFF,0x10,0x4F,0xA0,0xF8,0x17,
 116 +    0x46,0xA9,0xF1,0x1E,0x41,0xAE,0xF6,0x19,
 117 +    0x54,0xBB,0xE3,0x0C,0x53,0xBC,0xE4,0x0B,
 118 +    0x5A,0xB5,0xED,0x02,0x5D,0xB2,0xEA,0x05,
 119 +    0xE0,0x0F,0x57,0xB8,0xE7,0x08,0x50,0xBF,
 120 +    0xEE,0x01,0x59,0xB6,0xE9,0x06,0x5E,0xB1,
 121 +    0xFC,0x13,0x4B,0xA4,0xFB,0x14,0x4C,0xA3,
 122 +    0xF2,0x1D,0x45,0xAA,0xF5,0x1A,0x42,0xAD,
 123 +    0xD8,0x37,0x6F,0x80,0xDF,0x30,0x68,0x87,
 124 +    0xD6,0x39,0x61,0x8E,0xD1,0x3E,0x66,0x89,
 125 +    0xC4,0x2B,0x73,0x9C,0xC3,0x2C,0x74,0x9B,
 126 +    0xCA,0x25,0x7D,0x92,0xCD,0x22,0x7A,0x95,
 127 +    0x90,0x7F,0x27,0xC8,0x97,0x78,0x20,0xCF,
 128 +    0x9E,0x71,0x29,0xC6,0x99,0x76,0x2E,0xC1,
 129 +    0x8C,0x63,0x3B,0xD4,0x8B,0x64,0x3C,0xD3,
 130 +    0x82,0x6D,0x35,0xDA,0x85,0x6A,0x32,0xDD,
 131 +    0xA8,0x47,0x1F,0xF0,0xAF,0x40,0x18,0xF7,
 132 +    0xA6,0x49,0x11,0xFE,0xA1,0x4E,0x16,0xF9,
 133 +    0xB4,0x5B,0x03,0xEC,0xB3,0x5C,0x04,0xEB,
 134 +    0xBA,0x55,0x0D,0xE2,0xBD,0x52,0x0A,0xE5 };
 135 +
 136 +static inline DWORD mds_mul(BYTE *y)
 137 +{ DWORD z;
 138 +
 139 +  z=Mul_EF[y[0]] ^ y[1] ^ Mul_EF[y[2]] ^ Mul_5B[y[3]];
 140 +  z<<=8;
 141 +  z|=Mul_EF[y[0]] ^ Mul_5B[y[1]] ^ y[2] ^ Mul_EF[y[3]];
 142 +  z<<=8;
 143 +  z|=Mul_5B[y[0]] ^ Mul_EF[y[1]] ^ Mul_EF[y[2]] ^ y[3];
 144 +  z<<=8;
 145 +  z|=y[0] ^ Mul_EF[y[1]] ^ Mul_5B[y[2]] ^ Mul_5B[y[3]];
 146 +
 147 +  return z;
 148 +}
 149 +
 150 +/* q0 and q1 are the lookup substitutions done in twofish */
 151 +
 152 +static unsigned char q0[256] =
 153 +{      0xA9, 0x67, 0xB3, 0xE8, 0x04, 0xFD, 0xA3, 0x76,
 154 +       0x9A, 0x92, 0x80, 0x78, 0xE4, 0xDD, 0xD1, 0x38,
 155 +       0x0D, 0xC6, 0x35, 0x98, 0x18, 0xF7, 0xEC, 0x6C,
 156 +       0x43, 0x75, 0x37, 0x26, 0xFA, 0x13, 0x94, 0x48,
 157 +       0xF2, 0xD0, 0x8B, 0x30, 0x84, 0x54, 0xDF, 0x23,
 158 +       0x19, 0x5B, 0x3D, 0x59, 0xF3, 0xAE, 0xA2, 0x82,
 159 +       0x63, 0x01, 0x83, 0x2E, 0xD9, 0x51, 0x9B, 0x7C,
 160 +       0xA6, 0xEB, 0xA5, 0xBE, 0x16, 0x0C, 0xE3, 0x61,
 161 +       0xC0, 0x8C, 0x3A, 0xF5, 0x73, 0x2C, 0x25, 0x0B,
 162 +       0xBB, 0x4E, 0x89, 0x6B, 0x53, 0x6A, 0xB4, 0xF1,
 163 +       0xE1, 0xE6, 0xBD, 0x45, 0xE2, 0xF4, 0xB6, 0x66,
 164 +       0xCC, 0x95, 0x03, 0x56, 0xD4, 0x1C, 0x1E, 0xD7,
 165 +       0xFB, 0xC3, 0x8E, 0xB5, 0xE9, 0xCF, 0xBF, 0xBA,
 166 +       0xEA, 0x77, 0x39, 0xAF, 0x33, 0xC9, 0x62, 0x71,
 167 +       0x81, 0x79, 0x09, 0xAD, 0x24, 0xCD, 0xF9, 0xD8,
 168 +       0xE5, 0xC5, 0xB9, 0x4D, 0x44, 0x08, 0x86, 0xE7,
 169 +       0xA1, 0x1D, 0xAA, 0xED, 0x06, 0x70, 0xB2, 0xD2,
 170 +       0x41, 0x7B, 0xA0, 0x11, 0x31, 0xC2, 0x27, 0x90,
 171 +       0x20, 0xF6, 0x60, 0xFF, 0x96, 0x5C, 0xB1, 0xAB,
 172 +       0x9E, 0x9C, 0x52, 0x1B, 0x5F, 0x93, 0x0A, 0xEF,
 173 +       0x91, 0x85, 0x49, 0xEE, 0x2D, 0x4F, 0x8F, 0x3B,
 174 +       0x47, 0x87, 0x6D, 0x46, 0xD6, 0x3E, 0x69, 0x64,
 175 +       0x2A, 0xCE, 0xCB, 0x2F, 0xFC, 0x97, 0x05, 0x7A,
 176 +       0xAC, 0x7F, 0xD5, 0x1A, 0x4B, 0x0E, 0xA7, 0x5A,
 177 +       0x28, 0x14, 0x3F, 0x29, 0x88, 0x3C, 0x4C, 0x02,
 178 +       0xB8, 0xDA, 0xB0, 0x17, 0x55, 0x1F, 0x8A, 0x7D,
 179 +       0x57, 0xC7, 0x8D, 0x74, 0xB7, 0xC4, 0x9F, 0x72,
 180 +       0x7E, 0x15, 0x22, 0x12, 0x58, 0x07, 0x99, 0x34,
 181 +       0x6E, 0x50, 0xDE, 0x68, 0x65, 0xBC, 0xDB, 0xF8,
 182 +       0xC8, 0xA8, 0x2B, 0x40, 0xDC, 0xFE, 0x32, 0xA4,
 183 +       0xCA, 0x10, 0x21, 0xF0, 0xD3, 0x5D, 0x0F, 0x00,
 184 +       0x6F, 0x9D, 0x36, 0x42, 0x4A, 0x5E, 0xC1, 0xE0};
 185 +
 186 +static unsigned char q1[256] =
 187 +{      0x75, 0xF3, 0xC6, 0xF4, 0xDB, 0x7B, 0xFB, 0xC8,
 188 +       0x4A, 0xD3, 0xE6, 0x6B, 0x45, 0x7D, 0xE8, 0x4B,
 189 +       0xD6, 0x32, 0xD8, 0xFD, 0x37, 0x71, 0xF1, 0xE1,
 190 +       0x30, 0x0F, 0xF8, 0x1B, 0x87, 0xFA, 0x06, 0x3F,
 191 +       0x5E, 0xBA, 0xAE, 0x5B, 0x8A, 0x00, 0xBC, 0x9D,
 192 +       0x6D, 0xC1, 0xB1, 0x0E, 0x80, 0x5D, 0xD2, 0xD5,
 193 +       0xA0, 0x84, 0x07, 0x14, 0xB5, 0x90, 0x2C, 0xA3,
 194 +       0xB2, 0x73, 0x4C, 0x54, 0x92, 0x74, 0x36, 0x51,
 195 +       0x38, 0xB0, 0xBD, 0x5A, 0xFC, 0x60, 0x62, 0x96,
 196 +       0x6C, 0x42, 0xF7, 0x10, 0x7C, 0x28, 0x27, 0x8C,
 197 +       0x13, 0x95, 0x9C, 0xC7, 0x24, 0x46, 0x3B, 0x70,
 198 +       0xCA, 0xE3, 0x85, 0xCB, 0x11, 0xD0, 0x93, 0xB8,
 199 +       0xA6, 0x83, 0x20, 0xFF, 0x9F, 0x77, 0xC3, 0xCC,
 200 +       0x03, 0x6F, 0x08, 0xBF, 0x40, 0xE7, 0x2B, 0xE2,
 201 +       0x79, 0x0C, 0xAA, 0x82, 0x41, 0x3A, 0xEA, 0xB9,
 202 +       0xE4, 0x9A, 0xA4, 0x97, 0x7E, 0xDA, 0x7A, 0x17,
 203 +       0x66, 0x94, 0xA1, 0x1D, 0x3D, 0xF0, 0xDE, 0xB3,
 204 +       0x0B, 0x72, 0xA7, 0x1C, 0xEF, 0xD1, 0x53, 0x3E,
 205 +       0x8F, 0x33, 0x26, 0x5F, 0xEC, 0x76, 0x2A, 0x49,
 206 +       0x81, 0x88, 0xEE, 0x21, 0xC4, 0x1A, 0xEB, 0xD9,
 207 +       0xC5, 0x39, 0x99, 0xCD, 0xAD, 0x31, 0x8B, 0x01,
 208 +       0x18, 0x23, 0xDD, 0x1F, 0x4E, 0x2D, 0xF9, 0x48,
 209 +       0x4F, 0xF2, 0x65, 0x8E, 0x78, 0x5C, 0x58, 0x19,
 210 +       0x8D, 0xE5, 0x98, 0x57, 0x67, 0x7F, 0x05, 0x64,
 211 +       0xAF, 0x63, 0xB6, 0xFE, 0xF5, 0xB7, 0x3C, 0xA5,
 212 +       0xCE, 0xE9, 0x68, 0x44, 0xE0, 0x4D, 0x43, 0x69,
 213 +       0x29, 0x2E, 0xAC, 0x15, 0x59, 0xA8, 0x0A, 0x9E,
 214 +       0x6E, 0x47, 0xDF, 0x34, 0x35, 0x6A, 0xCF, 0xDC,
 215 +       0x22, 0xC9, 0xC0, 0x9B, 0x89, 0xD4, 0xED, 0xAB,
 216 +       0x12, 0xA2, 0x0D, 0x52, 0xBB, 0x02, 0x2F, 0xA9,
 217 +       0xD7, 0x61, 0x1E, 0xB4, 0x50, 0x04, 0xF6, 0xC2,
 218 +       0x16, 0x25, 0x86, 0x56, 0x55, 0x09, 0xBE, 0x91
 219 +       };
 220 +
 221 +
 222 +static DWORD f32(DWORD x, const DWORD * k32, int keyLen)
 223 +{
 224 +  BYTE b[4];
 225 +
 226 +  /* Run each byte thru 8x8 S-boxes, xoring with key byte at each stage. */
 227 +  /* Note that each byte goes through a different combination of S-boxes. */
 228 +
 229 +  *((DWORD *) b) = Bswap(x);   /* make b[0] = LSB, b[3] = MSB */
 230 +
 231 +  switch (((keyLen + 63) / 64) & 3)
 232 +  {
 233 +  case 0:                      /* 256 bits of key */
 234 +    b[0] = q1[b[0]];
 235 +    b[1] = q0[b[1]];
 236 +    b[2] = q0[b[2]];
 237 +    b[3] = q1[b[3]];
 238 +
 239 +    *((DWORD *) b) ^= k32[3];
 240 +
 241 +    /* fall thru, having pre-processed b[0]..b[3] with k32[3] */
 242 +  case 3:                      /* 192 bits of key */
 243 +    b[0] = q1[b[0]];
 244 +    b[1] = q1[b[1]];
 245 +    b[2] = q0[b[2]];
 246 +    b[3] = q0[b[3]];
 247 +
 248 +    *((DWORD *) b) ^= k32[2];
 249 +
 250 +    /* fall thru, having pre-processed b[0]..b[3] with k32[2] */
 251 +  case 2:                      /* 128 bits of key */
 252 +    b[0] = q0[b[0]];
 253 +    b[1] = q1[b[1]];
 254 +    b[2] = q0[b[2]];
 255 +    b[3] = q1[b[3]];
 256 +
 257 +    *((DWORD *) b) ^= k32[1];
 258 +
 259 +    b[0] = q0[b[0]];
 260 +    b[1] = q0[b[1]];
 261 +    b[2] = q1[b[2]];
 262 +    b[3] = q1[b[3]];
 263 +
 264 +    *((DWORD *) b) ^= k32[0];
 265 +
 266 +    b[0] = q1[b[0]];
 267 +    b[1] = q0[b[1]];
 268 +    b[2] = q1[b[2]];
 269 +    b[3] = q0[b[3]];
 270 +  }
 271 +
 272 +
 273 +  /* Now perform the MDS matrix multiply inline. */
 274 +  return mds_mul(b);
 275 +}
 276 +
 277 +
 278 +static void init_sbox(fish2_key *key)
 279 +{ DWORD x,*sbox,z,*k32;
 280 +  int i,keyLen;
 281 +  BYTE b[4];
 282 +
 283 +  k32=key->sboxKeys;
 284 +  keyLen=key->keyLen;
 285 +  sbox=key->sbox_full;
 286 +
 287 +  x=0;
 288 +  for (i=0;i<256;i++,x+=0x01010101)
 289 +  {
 290 +    *((DWORD *) b) = Bswap(x); /* make b[0] = LSB, b[3] = MSB */
 291 +
 292 +    switch (((keyLen + 63) / 64) & 3)
 293 +    {
 294 +    case 0:                    /* 256 bits of key */
 295 +      b[0] = q1[b[0]];
 296 +      b[1] = q0[b[1]];
 297 +      b[2] = q0[b[2]];
 298 +      b[3] = q1[b[3]];
 299 +
 300 +      *((DWORD *) b) ^= k32[3];
 301 +
 302 +      /* fall thru, having pre-processed b[0]..b[3] with k32[3] */
 303 +    case 3:                    /* 192 bits of key */
 304 +      b[0] = q1[b[0]];
 305 +      b[1] = q1[b[1]];
 306 +      b[2] = q0[b[2]];
 307 +      b[3] = q0[b[3]];
 308 +
 309 +      *((DWORD *) b) ^= k32[2];
 310 +
 311 +      /* fall thru, having pre-processed b[0]..b[3] with k32[2] */
 312 +    case 2:                    /* 128 bits of key */
 313 +      b[0] = q0[b[0]];
 314 +      b[1] = q1[b[1]];
 315 +      b[2] = q0[b[2]];
 316 +      b[3] = q1[b[3]];
 317 +
 318 +      *((DWORD *) b) ^= k32[1];
 319 +
 320 +      b[0] = q0[b[0]];
 321 +      b[1] = q0[b[1]];
 322 +      b[2] = q1[b[2]];
 323 +      b[3] = q1[b[3]];
 324 +
 325 +      *((DWORD *) b) ^= k32[0];
 326 +
 327 +      b[0] = q1[b[0]];
 328 +      b[1] = q0[b[1]];
 329 +      b[2] = q1[b[2]];
 330 +      b[3] = q0[b[3]];
 331 +    }
 332 +
 333 +    z=Mul_EF[b[0]];
 334 +    z<<=8;
 335 +    z|=Mul_EF[b[0]];
 336 +    z<<=8;
 337 +    z|=Mul_5B[b[0]];
 338 +    z<<=8;
 339 +    z|=b[0];
 340 +
 341 +    sbox[i]=z;
 342 +
 343 +    z=b[1];
 344 +    z<<=8;
 345 +    z|=Mul_5B[b[1]];
 346 +    z<<=8;
 347 +    z|=Mul_EF[b[1]];
 348 +    z<<=8;
 349 +    z|=Mul_EF[b[1]];
 350 +
 351 +    sbox[i+256]=z;
 352 +
 353 +    z=Mul_EF[b[2]];
 354 +    z<<=8;
 355 +    z|=b[2];
 356 +    z<<=8;
 357 +    z|=Mul_EF[b[2]];
 358 +    z<<=8;
 359 +    z|=Mul_5B[b[2]];
 360 +
 361 +    sbox[i+512]=z;
 362 +
 363 +    z=Mul_5B[b[3]];
 364 +    z<<=8;
 365 +    z|=Mul_EF[b[3]];
 366 +    z<<=8;
 367 +    z|=b[3];
 368 +    z<<=8;
 369 +    z|=Mul_5B[b[3]];
 370 +
 371 +    sbox[i+768]=z;
 372 +  }
 373 +}
 374 +
 375 +
 376 +/* Reed-Solomon code parameters: (12,8) reversible code
 377 +   g(x) = x**4 + (a + 1/a) x**3 + a x**2 + (a + 1/a) x + 1
 378 +   where a = primitive root of field generator 0x14D */
 379 +#define RS_GF_FDBK      0x14D   /* field generator */
 380 +#define RS_rem(x) \
 381 +    { BYTE  b  =   x >> 24; \
 382 +      DWORD g2 = ((b << 1) ^ ((b & 0x80) ? RS_GF_FDBK : 0 )) & 0xFF; \
 383 +      DWORD g3 = ((b >> 1) & 0x7F) ^ ((b & 1) ? RS_GF_FDBK >> 1 : 0 ) ^ g2 ; \
 384 +      x = (x << 8) ^ (g3 << 24) ^ (g2 << 16) ^ (g3 << 8) ^ b; \
 385 +    }
 386 +
 387 +static DWORD rs_mds(DWORD k0, DWORD k1)
 388 +{
 389 +  int i, j;
 390 +  DWORD r;
 391 +
 392 +  for (i = r = 0; i < 2; i++)
 393 +  {
 394 +    r ^= (i) ? k0 : k1;     /* merge in 32 more key bits */
 395 +    for (j = 0; j < 4; j++) /* shift one byte at a time */
 396 +      RS_rem(r);
 397 +  }
 398 +  return r;
 399 +}
 400 +
 401 +
 402 +#define                INPUT_WHITEN            0       /* subkey array indices */
 403 +#define                OUTPUT_WHITEN           4
 404 +#define                ROUND_SUBKEYS           8       /* use 2 * (# rounds) */
 405 +#define                TOTAL_SUBKEYS           40
 406 +
 407 +static void init_key(fish2_key * key)
 408 +{
 409 +  int i, k64Cnt;
 410 +  int keyLen = key->keyLen;
 411 +  int subkeyCnt = TOTAL_SUBKEYS;
 412 +  DWORD A, B;
 413 +  DWORD k32e[4], k32o[4];      /* even/odd key dwords */
 414 +
 415 +  k64Cnt = (keyLen + 63) / 64; /* round up to next multiple of 64 bits */
 416 +  for (i = 0; i < k64Cnt; i++)
 417 +  {                            /* split into even/odd key dwords */
 418 +    k32e[i] = ((DWORD *)key->key)[2 * i];
 419 +    k32o[i] = ((DWORD *)key->key)[2 * i + 1];
 420 +    /* compute S-box keys using (12,8) Reed-Solomon code over GF(256) */
 421 +    /* store in reverse order */
 422 +    key->sboxKeys[k64Cnt - 1 - i] =
 423 +      Bswap(rs_mds(Bswap(k32e[i]), Bswap(k32o[i])));
 424 +
 425 +  }
 426 +
 427 +  for (i = 0; i < subkeyCnt / 2; i++)  /* compute round subkeys for PHT */
 428 +  {
 429 +    A = f32(i * 0x02020202, k32e, keyLen);             /* A uses even key dwords */
 430 +    B = f32(i * 0x02020202 + 0x01010101, k32o, keyLen);        /* B uses odd  key
 431 +                                                          dwords */
 432 +    B = ROL(B, 8);
 433 +    key->subKeys[2 * i] = A + B;       /* combine with a PHT */
 434 +    key->subKeys[2 * i + 1] = ROL(A + 2 * B, 9);
 435 +  }
 436 +
 437 +  init_sbox(key);
 438 +}
 439 +
 440 +
 441 +static inline DWORD f32_sbox(DWORD x,DWORD *sbox)
 442 +{
 443 +  /* Run each byte thru 8x8 S-boxes, xoring with key byte at each stage. */
 444 +  /* Note that each byte goes through a different combination of S-boxes. */
 445 +
 446 +  return (sbox[        (x)     &0xff]^
 447 +          sbox[256 + (((x)>> 8)&0xff)]^
 448 +          sbox[512 + (((x)>>16)&0xff)]^
 449 +          sbox[768 + (((x)>>24)&0xff)]);
 450 +}
 451 +
 452 +#define roundE_m(x0,x1,x2,x3,rnd) \
 453 +      t0 = f32_sbox( x0, key->sbox_full ) ; \
 454 +      t1 = f32_sbox( ROL(x1,8), key->sbox_full ); \
 455 +      x2 ^= t0 + t1 + key->subKeys[2*rnd+8]; \
 456 +      x3 = ROL(x3,1); \
 457 +      x3 ^= t0 + 2*t1 + key->subKeys[2*rnd+9]; \
 458 +      x2 = ROR(x2,1);
 459 +
 460 +
 461 +static int blockEncrypt_CBC(fish2_key *key,BYTE *src,BYTE *dst,int len)
 462 +{ DWORD xx0,xx1,xx2,xx3,t0,t1,iv0,iv1,iv2,iv3;
 463 +
 464 +  if (len & 0xF) return -1;
 465 +
 466 +  iv0=0;
 467 +  iv1=0;
 468 +  iv2=0;
 469 +  iv3=0;
 470 +  for (;len>=16;len-=16)
 471 +
 472 +  {
 473 +    if ( ( len & 0x1FF) == 0)
 474 +    { iv0=0;
 475 +      iv1=0;
 476 +      iv2=0;
 477 +      iv3=0;
 478 +    }
 479 +
 480 +    xx0=Bswap(((DWORD *)src)[0]) ^ key->subKeys[0] ^ iv0;
 481 +    xx1=Bswap(((DWORD *)src)[1]) ^ key->subKeys[1] ^ iv1;
 482 +    xx2=Bswap(((DWORD *)src)[2]) ^ key->subKeys[2] ^ iv2;
 483 +    xx3=Bswap(((DWORD *)src)[3]) ^ key->subKeys[3] ^ iv3;
 484 +
 485 +    src+=16;
 486 +
 487 +    roundE_m(xx0,xx1,xx2,xx3,0);
 488 +    roundE_m(xx2,xx3,xx0,xx1,1);
 489 +    roundE_m(xx0,xx1,xx2,xx3,2);
 490 +    roundE_m(xx2,xx3,xx0,xx1,3);
 491 +    roundE_m(xx0,xx1,xx2,xx3,4);
 492 +    roundE_m(xx2,xx3,xx0,xx1,5);
 493 +    roundE_m(xx0,xx1,xx2,xx3,6);
 494 +    roundE_m(xx2,xx3,xx0,xx1,7);
 495 +    roundE_m(xx0,xx1,xx2,xx3,8);
 496 +    roundE_m(xx2,xx3,xx0,xx1,9);
 497 +    roundE_m(xx0,xx1,xx2,xx3,10);
 498 +    roundE_m(xx2,xx3,xx0,xx1,11);
 499 +    roundE_m(xx0,xx1,xx2,xx3,12);
 500 +    roundE_m(xx2,xx3,xx0,xx1,13);
 501 +    roundE_m(xx0,xx1,xx2,xx3,14);
 502 +    roundE_m(xx2,xx3,xx0,xx1,15);
 503 +
 504 +    iv0=xx2 ^ key->subKeys[4];
 505 +    iv1=xx3 ^ key->subKeys[5];
 506 +    iv2=xx0 ^ key->subKeys[6];
 507 +    iv3=xx1 ^ key->subKeys[7];
 508 +
 509 +    ((DWORD *)dst)[0] = Bswap(iv0);
 510 +    ((DWORD *)dst)[1] = Bswap(iv1);
 511 +    ((DWORD *)dst)[2] = Bswap(iv2);
 512 +    ((DWORD *)dst)[3] = Bswap(iv3);
 513 +    dst+=16;
 514 +  }
 515 +  return len;
 516 +}
 517 +
 518 +#define roundD_m(x0,x1,x2,x3,rnd) \
 519 +      t0 = f32_sbox( x0, key->sbox_full); \
 520 +      t1 = f32_sbox( ROL(x1,8),key->sbox_full); \
 521 +      x2 = ROL(x2,1); \
 522 +      x3 ^= t0 + 2*t1 + key->subKeys[rnd*2+9]; \
 523 +      x3 = ROR(x3,1); \
 524 +      x2 ^= t0 + t1 + key->subKeys[rnd*2+8];
 525 +
 526 +
 527 +static int blockDecrypt_CBC(fish2_key *key,BYTE *src,BYTE *dst,int len)
 528 +{ DWORD xx0,xx1,xx2,xx3,t0,t1,lx0,lx1,lx2,lx3,iv0,iv1,iv2,iv3;
 529 +
 530 +  if (len & 0xF) return -1;
 531 +
 532 +  iv0=0;
 533 +  iv1=0;
 534 +  iv2=0;
 535 +  iv3=0;
 536 +
 537 +  for (;len>=16;len-=16)
 538 +  {
 539 +    if ( ( len & 0x1FF) == 0)
 540 +    { iv0=0;
 541 +      iv1=0;
 542 +      iv2=0;
 543 +      iv3=0;
 544 +    }
 545 +
 546 +    lx0=iv0;iv0=Bswap(((DWORD *)src)[0]);xx0=iv0 ^ key->subKeys[4];
 547 +    lx1=iv1;iv1=Bswap(((DWORD *)src)[1]);xx1=iv1 ^ key->subKeys[5];
 548 +    lx2=iv2;iv2=Bswap(((DWORD *)src)[2]);xx2=iv2 ^ key->subKeys[6];
 549 +    lx3=iv3;iv3=Bswap(((DWORD *)src)[3]);xx3=iv3 ^ key->subKeys[7];
 550 +    src+=16;
 551 +
 552 +    roundD_m(xx0,xx1,xx2,xx3,15);
 553 +    roundD_m(xx2,xx3,xx0,xx1,14);
 554 +    roundD_m(xx0,xx1,xx2,xx3,13);
 555 +    roundD_m(xx2,xx3,xx0,xx1,12);
 556 +    roundD_m(xx0,xx1,xx2,xx3,11);
 557 +    roundD_m(xx2,xx3,xx0,xx1,10);
 558 +    roundD_m(xx0,xx1,xx2,xx3,9);
 559 +    roundD_m(xx2,xx3,xx0,xx1,8);
 560 +    roundD_m(xx0,xx1,xx2,xx3,7);
 561 +    roundD_m(xx2,xx3,xx0,xx1,6);
 562 +    roundD_m(xx0,xx1,xx2,xx3,5);
 563 +    roundD_m(xx2,xx3,xx0,xx1,4);
 564 +    roundD_m(xx0,xx1,xx2,xx3,3);
 565 +    roundD_m(xx2,xx3,xx0,xx1,2);
 566 +    roundD_m(xx0,xx1,xx2,xx3,1);
 567 +    roundD_m(xx2,xx3,xx0,xx1,0);
 568 +
 569 +    ((DWORD *)dst)[0] = Bswap(xx2 ^ key->subKeys[0] ^ lx0);
 570 +    ((DWORD *)dst)[1] = Bswap(xx3 ^ key->subKeys[1] ^ lx1);
 571 +    ((DWORD *)dst)[2] = Bswap(xx0 ^ key->subKeys[2] ^ lx2);
 572 +    ((DWORD *)dst)[3] = Bswap(xx1 ^ key->subKeys[3] ^ lx3);
 573 +    dst+=16;
 574 +  }
 575 +  return len;
 576 +}
 577 +
 578 +
 579 +int transfer_fish2(struct loop_device *lo, int cmd,
 580 +                   struct page *raw_page, unsigned raw_off,
 581 +                   struct page *loop_page, unsigned loop_off,
 582 +                   int size, sector_t IV)
 583 +{
 584 +  char *raw_buf = kmap_atomic(raw_page, KM_USER0) + raw_off;
 585 +  char *loop_buf = kmap_atomic(loop_page, KM_USER1) + loop_off;
 586 +
 587 +  if (cmd == READ)
 588 +    blockDecrypt_CBC((fish2_key *)lo->key_data,raw_buf,loop_buf,size);
 589 +  else
 590 +    blockEncrypt_CBC((fish2_key *)lo->key_data,loop_buf,raw_buf,size);
 591 +
 592 +  kunmap_atomic(raw_buf, KM_USER0);
 593 +  kunmap_atomic(loop_buf, KM_USER1);
 594 +  cond_resched();
 595 +
 596 +  return 0;
 597 +}
 598 +
 599 +int fish2_init(struct loop_device *lo,const struct loop_info64 *info)
 600 +{ fish2_key *key;
 601 +
 602 +  if (info->lo_encrypt_key_size<16 || info->lo_encrypt_key_size>32)
 603 +    return -EINVAL;
 604 +
 605 +  key=(fish2_key *)kmalloc(sizeof(fish2_key),GFP_KERNEL);
 606 +
 607 +  if (key==NULL)
 608 +    return -ENOMEM;
 609 +
 610 +  lo->key_data=key;
 611 +
 612 +  memset(key->key,0,32);
 613 +
 614 +  key->keyLen=info->lo_encrypt_key_size << 3;
 615 +  memcpy(key->key,info->lo_encrypt_key,info->lo_encrypt_key_size);
 616 +
 617 +  init_key(key);
 618 +
 619 +  return 0;
 620 +}
 621 +
 622 +static int fish2_release(struct loop_device *lo)
 623 +{ if (lo->key_data!=NULL)
 624 +  {
 625 +    kfree(lo->key_data);
 626 +    lo->key_data=NULL;
 627 +  }
 628 +  return(0);
 629 +}
 630 +
 631 +static struct loop_func_table fish2_funcs =
 632 +{ .number = LO_CRYPT_FISH2,
 633 +  .transfer = transfer_fish2,
 634 +  .init = fish2_init,
 635 +  .release = fish2_release,
 636 +  .owner = THIS_MODULE
 637 +};
 638 +
 639 +int __init loop_fish2_init(void)
 640 +{
 641 +  int err;
 642 +
 643 +  if ((err=loop_register_transfer(&fish2_funcs)))
 644 +  {
 645 +    printk(KERN_WARNING "Couldn't register Twofish encryption\n");
 646 +    return err;
 647 +  }
 648 +  printk(KERN_INFO "loop: registered Twofish encryption \n");
 649 +  return 0;
 650 +}
 651 +
 652 +void __exit loop_fish2_exit(void)
 653 +{
 654 +  if (loop_unregister_transfer(LO_CRYPT_FISH2))
 655 +    printk(KERN_WARNING "Couldn't unregister Twofish encryption\n");
 656 +  printk(KERN_INFO "loop: unregistered Twofish encryption \n");
 657 +}
 658 +
 659 +module_init(loop_fish2_init);
 660 +module_exit(loop_fish2_exit);
 661 +MODULE_LICENSE("GPL");