loop_serpent.c

Fast and transparent file system and swap encryption package for linux. No source code changes to li

    if (key_len < 256)
    {
        while(i < 8)

            l_key[i++] = 0;

        i = key_len / 32; lk = 1 << key_len % 32; 

        l_key[i] &= lk - 1;
        l_key[i] |= lk;
    }

    for(i = 0; i < 132; ++i)
    {
        lk = l_key[i] ^ l_key[i + 3] ^ l_key[i + 5] 
                                ^ l_key[i + 7] ^ 0x9e3779b9 ^ i;

        l_key[i + 8] = (lk << 11) | (lk >> 21); 
    }

      GETKEY(r0, r1, r2, r3, 0);
      S3(r0,r1,r2,r3,r4);
      SETKEY(r1, r2, r3, r4, 0) 

      GETKEY(r0, r1, r2, r3, 4);
      S2(r0,r1,r2,r3,r4);
      SETKEY(r2, r3, r1, r4, 4) 

      GETKEY(r0, r1, r2, r3, 8);
      S1(r0,r1,r2,r3,r4);
      SETKEY(r3, r1, r2, r0, 8) 

      GETKEY(r0, r1, r2, r3, 12);
      S0(r0,r1,r2,r3,r4);
      SETKEY(r1, r4, r2, r0, 12) 

      GETKEY(r0, r1, r2, r3, 16);
      S7(r0,r1,r2,r3,r4);
      SETKEY(r2, r4, r3, r0, 16) 

      GETKEY(r0, r1, r2, r3, 20);
      S6(r0,r1,r2,r3,r4) 
      SETKEY(r0, r1, r4, r2, 20) 

      GETKEY(r0, r1, r2, r3, 24);
      S5(r0,r1,r2,r3,r4);
      SETKEY(r1, r3, r0, r2, 24) 

      GETKEY(r0, r1, r2, r3, 28);
      S4(r0,r1,r2,r3,r4) 
      SETKEY(r1, r4, r0, r3, 28) 

      GETKEY(r0, r1, r2, r3, 32);
      S3(r0,r1,r2,r3,r4);
      SETKEY(r1, r2, r3, r4, 32) 

      GETKEY(r0, r1, r2, r3, 36);
      S2(r0,r1,r2,r3,r4);
      SETKEY(r2, r3, r1, r4, 36) 

      GETKEY(r0, r1, r2, r3, 40);
      S1(r0,r1,r2,r3,r4);
      SETKEY(r3, r1, r2, r0, 40) 

      GETKEY(r0, r1, r2, r3, 44);
      S0(r0,r1,r2,r3,r4);
      SETKEY(r1, r4, r2, r0, 44) 

      GETKEY(r0, r1, r2, r3, 48);
      S7(r0,r1,r2,r3,r4);
      SETKEY(r2, r4, r3, r0, 48) 

      GETKEY(r0, r1, r2, r3, 52);
      S6(r0,r1,r2,r3,r4) 
      SETKEY(r0, r1, r4, r2, 52) 

      GETKEY(r0, r1, r2, r3, 56);
      S5(r0,r1,r2,r3,r4);
      SETKEY(r1, r3, r0, r2, 56) 

      GETKEY(r0, r1, r2, r3, 60);
      S4(r0,r1,r2,r3,r4) 
      SETKEY(r1, r4, r0, r3, 60) 

      GETKEY(r0, r1, r2, r3, 64);
      S3(r0,r1,r2,r3,r4);
      SETKEY(r1, r2, r3, r4, 64) 

      GETKEY(r0, r1, r2, r3, 68);
      S2(r0,r1,r2,r3,r4);
      SETKEY(r2, r3, r1, r4, 68) 

      GETKEY(r0, r1, r2, r3, 72);
      S1(r0,r1,r2,r3,r4);
      SETKEY(r3, r1, r2, r0, 72) 

      GETKEY(r0, r1, r2, r3, 76);
      S0(r0,r1,r2,r3,r4);
      SETKEY(r1, r4, r2, r0, 76) 

      GETKEY(r0, r1, r2, r3, 80);
      S7(r0,r1,r2,r3,r4);
      SETKEY(r2, r4, r3, r0, 80) 

      GETKEY(r0, r1, r2, r3, 84);
      S6(r0,r1,r2,r3,r4) 
      SETKEY(r0, r1, r4, r2, 84) 

      GETKEY(r0, r1, r2, r3, 88);
      S5(r0,r1,r2,r3,r4);
      SETKEY(r1, r3, r0, r2, 88) 

      GETKEY(r0, r1, r2, r3, 92);
      S4(r0,r1,r2,r3,r4) 
      SETKEY(r1, r4, r0, r3, 92) 

      GETKEY(r0, r1, r2, r3, 96);
      S3(r0,r1,r2,r3,r4);
      SETKEY(r1, r2, r3, r4, 96) 

      GETKEY(r0, r1, r2, r3, 100);
      S2(r0,r1,r2,r3,r4);
      SETKEY(r2, r3, r1, r4, 100) 

      GETKEY(r0, r1, r2, r3, 104);
      S1(r0,r1,r2,r3,r4);
      SETKEY(r3, r1, r2, r0, 104) 

      GETKEY(r0, r1, r2, r3, 108);
      S0(r0,r1,r2,r3,r4);
      SETKEY(r1, r4, r2, r0, 108) 

      GETKEY(r0, r1, r2, r3, 112);
      S7(r0,r1,r2,r3,r4);
      SETKEY(r2, r4, r3, r0, 112) 

      GETKEY(r0, r1, r2, r3, 116);
      S6(r0,r1,r2,r3,r4) 
      SETKEY(r0, r1, r4, r2, 116) 

      GETKEY(r0, r1, r2, r3, 120);
      S5(r0,r1,r2,r3,r4);
      SETKEY(r1, r3, r0, r2, 120) 

      GETKEY(r0, r1, r2, r3, 124);
      S4(r0,r1,r2,r3,r4) 
      SETKEY(r1, r4, r0, r3, 124) 

      GETKEY(r0, r1, r2, r3, 128);
      S3(r0,r1,r2,r3,r4);
      SETKEY(r1, r2, r3, r4, 128) 
};

/* Encryption and decryption functions. The rounds are fully inlined. 
 * The sboxes alters the bit order of the output, and the altered
 * bit ordrer is used progressivly. */

/* encrypt a block of text */

static void serpent_encrypt(u32 *l_key, const u8 *in, u8 *out, int wrongByteOrder)
{
     const u32 *in_blk = (u32 *) in;
     u32 *out_blk = (u32 *) out;
     u32  r0,r1,r2,r3,r4;
    
      if (wrongByteOrder) {
          /* incorrect byte order */
          r0 = io_swap_be(in_blk[3]);
          r1 = io_swap_be(in_blk[2]);
          r2 = io_swap_be(in_blk[1]);
          r3 = io_swap_be(in_blk[0]);
      } else {
          /* correct byte order */
          r0 = io_swap_le(in_blk[0]);
          r1 = io_swap_le(in_blk[1]);
          r2 = io_swap_le(in_blk[2]);
          r3 = io_swap_le(in_blk[3]);
      }

      /* round 1  */
      KEYMIX(r0,r1,r2,r3,r4,0);
      S0(r0,r1,r2,r3,r4);
      LINTRANS(r1,r4,r2,r0,r3);

      /* round 2  */
      KEYMIX(r1,r4,r2,r0,r3,4);
      S1(r1,r4,r2,r0,r3);
      LINTRANS(r0,r4,r2,r1,r3);

      /* round 3  */
      KEYMIX(r0,r4,r2,r1,r3,8);
      S2(r0,r4,r2,r1,r3);
      LINTRANS(r2,r1,r4,r3,r0);

      /* round 4  */
      KEYMIX(r2,r1,r4,r3,r0,12);
      S3(r2,r1,r4,r3,r0);
      LINTRANS(r1,r4,r3,r0,r2);

      /* round 5  */
      KEYMIX(r1,r4,r3,r0,r2,16);
      S4(r1,r4,r3,r0,r2) 
      LINTRANS(r4,r2,r1,r0,r3);

      /* round 6  */
      KEYMIX(r4,r2,r1,r0,r3,20);
      S5(r4,r2,r1,r0,r3);
      LINTRANS(r2,r0,r4,r1,r3);

      /* round 7  */
      KEYMIX(r2,r0,r4,r1,r3,24);
      S6(r2,r0,r4,r1,r3) 
      LINTRANS(r2,r0,r3,r4,r1);

      /* round 8  */
      KEYMIX(r2,r0,r3,r4,r1,28);
      S7(r2,r0,r3,r4,r1);
      LINTRANS(r3,r1,r4,r2,r0);

      /* round 9  */
      KEYMIX(r3,r1,r4,r2,r0,32);
      S0(r3,r1,r4,r2,r0);
      LINTRANS(r1,r0,r4,r3,r2);

      /* round 10  */
      KEYMIX(r1,r0,r4,r3,r2,36);
      S1(r1,r0,r4,r3,r2);
      LINTRANS(r3,r0,r4,r1,r2);

      /* round 11  */
      KEYMIX(r3,r0,r4,r1,r2,40);
      S2(r3,r0,r4,r1,r2);
      LINTRANS(r4,r1,r0,r2,r3);

      /* round 12  */
      KEYMIX(r4,r1,r0,r2,r3,44);
      S3(r4,r1,r0,r2,r3);
      LINTRANS(r1,r0,r2,r3,r4);

      /* round 13  */
      KEYMIX(r1,r0,r2,r3,r4,48);
      S4(r1,r0,r2,r3,r4) 
      LINTRANS(r0,r4,r1,r3,r2);

      /* round 14  */
      KEYMIX(r0,r4,r1,r3,r2,52);
      S5(r0,r4,r1,r3,r2);
      LINTRANS(r4,r3,r0,r1,r2);

      /* round 15  */
      KEYMIX(r4,r3,r0,r1,r2,56);
      S6(r4,r3,r0,r1,r2) 
      LINTRANS(r4,r3,r2,r0,r1);

      /* round 16  */
      KEYMIX(r4,r3,r2,r0,r1,60);
      S7(r4,r3,r2,r0,r1);
      LINTRANS(r2,r1,r0,r4,r3);

      /* round 17  */
      KEYMIX(r2,r1,r0,r4,r3,64);
      S0(r2,r1,r0,r4,r3);
      LINTRANS(r1,r3,r0,r2,r4);

      /* round 18  */
      KEYMIX(r1,r3,r0,r2,r4,68);
      S1(r1,r3,r0,r2,r4);
      LINTRANS(r2,r3,r0,r1,r4);

      /* round 19  */
      KEYMIX(r2,r3,r0,r1,r4,72);
      S2(r2,r3,r0,r1,r4);
      LINTRANS(r0,r1,r3,r4,r2);

      /* round 20  */
      KEYMIX(r0,r1,r3,r4,r2,76);
      S3(r0,r1,r3,r4,r2);
      LINTRANS(r1,r3,r4,r2,r0);

      /* round 21  */
      KEYMIX(r1,r3,r4,r2,r0,80);
      S4(r1,r3,r4,r2,r0) 
      LINTRANS(r3,r0,r1,r2,r4);

      /* round 22  */
      KEYMIX(r3,r0,r1,r2,r4,84);
      S5(r3,r0,r1,r2,r4);
      LINTRANS(r0,r2,r3,r1,r4);

      /* round 23  */
      KEYMIX(r0,r2,r3,r1,r4,88);
      S6(r0,r2,r3,r1,r4) 
      LINTRANS(r0,r2,r4,r3,r1);

      /* round 24  */
      KEYMIX(r0,r2,r4,r3,r1,92);
      S7(r0,r2,r4,r3,r1);
      LINTRANS(r4,r1,r3,r0,r2);

      /* round 25  */
      KEYMIX(r4,r1,r3,r0,r2,96);
      S0(r4,r1,r3,r0,r2);
      LINTRANS(r1,r2,r3,r4,r0);

      /* round 26  */
      KEYMIX(r1,r2,r3,r4,r0,100);
      S1(r1,r2,r3,r4,r0);
      LINTRANS(r4,r2,r3,r1,r0);

      /* round 27  */
      KEYMIX(r4,r2,r3,r1,r0,104);
      S2(r4,r2,r3,r1,r0);
      LINTRANS(r3,r1,r2,r0,r4);

      /* round 28  */
      KEYMIX(r3,r1,r2,r0,r4,108);
      S3(r3,r1,r2,r0,r4);
      LINTRANS(r1,r2,r0,r4,r3);

      /* round 29  */
      KEYMIX(r1,r2,r0,r4,r3,112);
      S4(r1,r2,r0,r4,r3) 
      LINTRANS(r2,r3,r1,r4,r0);

      /* round 30  */
      KEYMIX(r2,r3,r1,r4,r0,116);
      S5(r2,r3,r1,r4,r0);
      LINTRANS(r3,r4,r2,r1,r0);

      /* round 31  */
      KEYMIX(r3,r4,r2,r1,r0,120);
      S6(r3,r4,r2,r1,r0) 
      LINTRANS(r3,r4,r0,r2,r1);

      /* round 32  */
      KEYMIX(r3,r4,r0,r2,r1,124);
      S7(r3,r4,r0,r2,r1);
      KEYMIX(r0,r1,r2,r3,r4,128);

      if (wrongByteOrder) {
          /* incorrect byte order */
          out_blk[3] = io_swap_be(r0);
          out_blk[2] = io_swap_be(r1); 
          out_blk[1] = io_swap_be(r2);
          out_blk[0] = io_swap_be(r3);
      } else {
          /* correct byte order */
          out_blk[0] = io_swap_le(r0);
          out_blk[1] = io_swap_le(r1); 
          out_blk[2] = io_swap_le(r2);
          out_blk[3] = io_swap_le(r3);
      }
};

/* decrypt a block of text  */

static void serpent_decrypt(u32 *l_key, const u8 *in, u8 *out, int wrongByteOrder)
{
    const u32 *in_blk = (const u32 *)in;
    u32 *out_blk = (u32 *)out;
    u32  r0,r1,r2,r3,r4;
    
      if (wrongByteOrder) {
          /* incorrect byte order */
          r0 = io_swap_be(in_blk[3]);
          r1 = io_swap_be(in_blk[2]);
          r2 = io_swap_be(in_blk[1]);
          r3 = io_swap_be(in_blk[0]);
      } else {
          /* correct byte order */
          r0 = io_swap_le(in_blk[0]);
          r1 = io_swap_le(in_blk[1]); 
          r2 = io_swap_le(in_blk[2]);
          r3 = io_swap_le(in_blk[3]);
      }

      /* round 1 */
      KEYMIX(r0,r1,r2,r3,r4,128);
      I7(r0,r1,r2,r3,r4);
      KEYMIX(r3,r0,r1,r4,r2,124);

      /* round 2  */
      ILINTRANS(r3,r0,r1,r4,r2);
      I6(r3,r0,r1,r4,r2);
      KEYMIX(r0,r1,r2,r4,r3,120);

      /* round 3  */
      ILINTRANS(r0,r1,r2,r4,r3);
      I5(r0,r1,r2,r4,r3);
      KEYMIX(r1,r3,r4,r2,r0,116);

      /* round 4  */
      ILINTRANS(r1,r3,r4,r2,r0);
      I4(r1,r3,r4,r2,r0);
      KEYMIX(r1,r2,r4,r0,r3,112);

      /* round 5  */
      ILINTRANS(r1,r2,r4,r0,r3);
      I3(r1,r2,r4,r0,r3);
      KEYMIX(r4,r2,r0,r1,r3,108);

      /* round 6  */
      ILINTRANS(r4,r2,r0,r1,r3);
      I2(r4,r2,r0,r1,r3);
      KEYMIX(r2,r3,r0,r1,r4,104);

      /* round 7  */
      ILINTRANS(r2,r3,r0,r1,r4);
      I1(r2,r3,r0,r1,r4);
      KEYMIX(r4,r2,r1,r0,r3,100);

      /* round 8  */
      ILINTRANS(r4,r2,r1,r0,r3);
      I0(r4,r2,r1,r0,r3);
      KEYMIX(r4,r3,r2,r0,r1,96);

      /* round 9  */
      ILINTRANS(r4,r3,r2,r0,r1);
      I7(r4,r3,r2,r0,r1);
      KEYMIX(r0,r4,r3,r1,r2,92);

      /* round 10  */
      ILINTRANS(r0,r4,r3,r1,r2);
      I6(r0,r4,r3,r1,r2);
      KEYMIX(r4,r3,r2,r1,r0,88);

      /* round 11  */
      ILINTRANS(r4,r3,r2,r1,r0);
      I5(r4,r3,r2,r1,r0);
      KEYMIX(r3,r0,r1,r2,r4,84);

      /* round 12  */
      ILINTRANS(r3,r0,r1,r2,r4);
      I4(r3,r0,r1,r2,r4);
      KEYMIX(r3,r2,r1,r4,r0,80);

      /* round 13  */
      ILINTRANS(r3,r2,r1,r4,r0);
      I3(r3,r2,r1,r4,r0);
      KEYMIX(r1,r2,r4,r3,r0,76);

      /* round 14  */
      ILINTRANS(r1,r2,r4,r3,r0);
      I2(r1,r2,r4,r3,r0);
      KEYMIX(r2,r0,r4,r3,r1,72);

      /* round 15  */
      ILINTRANS(r2,r0,r4,r3,r1);
      I1(r2,r0,r4,r3,r1);
      KEYMIX(r1,r2,r3,r4,r0,68);

      /* round 16  */
      ILINTRANS(r1,r2,r3,r4,r0);
      I0(r1,r2,r3,r4,r0);
      KEYMIX(r1,r0,r2,r4,r3,64);

      /* round 17  */
      ILINTRANS(r1,r0,r2,r4,r3);
      I7(r1,r0,r2,r4,r3);
      KEYMIX(r4,r1,r0,r3,r2,60);

      /* round 18  */
      ILINTRANS(r4,r1,r0,r3,r2);
      I6(r4,r1,r0,r3,r2);
      KEYMIX(r1,r0,r2,r3,r4,56);

      /* round 19  */
      ILINTRANS(r1,r0,r2,r3,r4);
      I5(r1,r0,r2,r3,r4);
      KEYMIX(r0,r4,r3,r2,r1,52);

      /* round 20  */