/*
 * This is D3DES (V5.09) by Richard Outerbridge with the double and
 * triple-length support removed for use in VNC.  Also the bytebit[] array
 * has been reversed so that the most significant bit in each byte of the
 * key is ignored, not the least significant.
 *
 * These changes are:
 *  Copyright (C) 1999 AT&T Laboratories Cambridge.  All Rights Reserved.
 *
 * This software is distributed in the hope that it will be useful,
 * but WITHOUT ANY WARRANTY; without even the implied warranty of
 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.
 */

/* D3DES (V5.09) -
 *
 * A portable, public domain, version of the Data Encryption Standard.
 *
 * Written with Symantec's THINK (Lightspeed) C by Richard Outerbridge.
 * Thanks to: Dan Hoey for his excellent Initial and Inverse permutation
 * code;  Jim Gillogly & Phil Karn for the DES key schedule code; Dennis
 * Ferguson, Eric Young and Dana How for comparing notes; and Ray Lau,
 * for humouring me on.
 *
 * Copyright (c) 1988,1989,1990,1991,1992 by Richard Outerbridge.
 * (GEnie : OUTER; CIS : [71755,204]) Graven Imagery, 1992.
 */

#ifdef HAVE_CONFIG_H
#include "config.h"
#endif

#ifdef HAVE_STDINT_H
#include <stdint.h>
#endif

#include "d3des.h"

static void scrunch (unsigned char *, unsigned long *);
static void unscrun (unsigned long *, unsigned char *);
static void desfunc (unsigned long *, unsigned long *);
static void cookey (DESContext * ctx, unsigned long *);

//static const unsigned long KnL[32] = { 0L };

//static const unsigned long KnR[32] = { 0L };
//static const unsigned long Kn3[32] = { 0L };
/* 
 * static const unsigned char Df_Key[24] = {
 * 	0x01,0x23,0x45,0x67,0x89,0xab,0xcd,0xef,
 * 	0xfe,0xdc,0xba,0x98,0x76,0x54,0x32,0x10,
 * 	0x89,0xab,0xcd,0xef,0x01,0x23,0x45,0x67 };
 */

static const uint16_t bytebit[8] = {
  01, 02, 04, 010, 020, 040, 0100, 0200
};

static const unsigned long bigbyte[24] = {
  0x800000L, 0x400000L, 0x200000L, 0x100000L,
  0x80000L, 0x40000L, 0x20000L, 0x10000L,
  0x8000L, 0x4000L, 0x2000L, 0x1000L,
  0x800L, 0x400L, 0x200L, 0x100L,
  0x80L, 0x40L, 0x20L, 0x10L,
  0x8L, 0x4L, 0x2L, 0x1L
};

/* Use the key schedule specified in the Standard (ANSI X3.92-1981). */

static const unsigned char pc1[56] = {
  56, 48, 40, 32, 24, 16, 8, 0, 57, 49, 41, 33, 25, 17,
  9, 1, 58, 50, 42, 34, 26, 18, 10, 2, 59, 51, 43, 35,
  62, 54, 46, 38, 30, 22, 14, 6, 61, 53, 45, 37, 29, 21,
  13, 5, 60, 52, 44, 36, 28, 20, 12, 4, 27, 19, 11, 3
};

static const unsigned char totrot[16] = {
  1, 2, 4, 6, 8, 10, 12, 14, 15, 17, 19, 21, 23, 25, 27, 28
};

static const unsigned char pc2[48] = {
  13, 16, 10, 23, 0, 4, 2, 27, 14, 5, 20, 9,
  22, 18, 11, 3, 25, 7, 15, 6, 26, 19, 12, 1,
  40, 51, 30, 36, 46, 54, 29, 39, 50, 44, 32, 47,
  43, 48, 38, 55, 33, 52, 45, 41, 49, 35, 28, 31
};

void
deskey (DESContext * ctx, unsigned char *key, int32_t edf)
{                               /* Thanks to James Gillogly & Phil Karn! */
  register int32_t i, j, l, m, n;
  unsigned char pc1m[56], pcr[56];
  unsigned long kn[32];

  for (j = 0; j < 56; j++) {
    l = pc1[j];
    m = l & 07;
    pc1m[j] = (key[l >> 3] & bytebit[m]) ? 1 : 0;
  }
  for (i = 0; i < 16; i++) {
    if (edf == DE1)
      m = (15 - i) << 1;
    else
      m = i << 1;
    n = m + 1;
    kn[m] = kn[n] = 0L;
    for (j = 0; j < 28; j++) {
      l = j + totrot[i];
      if (l < 28)
        pcr[j] = pc1m[l];
      else
        pcr[j] = pc1m[l - 28];
    }
    for (j = 28; j < 56; j++) {
      l = j + totrot[i];
      if (l < 56)
        pcr[j] = pc1m[l];
      else
        pcr[j] = pc1m[l - 28];
    }
    for (j = 0; j < 24; j++) {
      if (pcr[pc2[j]])
        kn[m] |= bigbyte[j];
      if (pcr[pc2[j + 24]])
        kn[n] |= bigbyte[j];
    }
  }
  cookey (ctx, kn);
  return;
}

static void
cookey (DESContext * ctx, register unsigned long *raw1)
{
  register unsigned long *cook, *raw0;
  unsigned long dough[32];
  register int32_t i;

  cook = dough;
  for (i = 0; i < 16; i++, raw1++) {
    raw0 = raw1++;
    *cook = (*raw0 & 0x00fc0000L) << 6;
    *cook |= (*raw0 & 0x00000fc0L) << 10;
    *cook |= (*raw1 & 0x00fc0000L) >> 10;
    *cook++ |= (*raw1 & 0x00000fc0L) >> 6;
    *cook = (*raw0 & 0x0003f000L) << 12;
    *cook |= (*raw0 & 0x0000003fL) << 16;
    *cook |= (*raw1 & 0x0003f000L) >> 4;
    *cook++ |= (*raw1 & 0x0000003fL);
  }
  usekey (ctx, dough);
  return;
}

void
cpkey (DESContext * ctx, register unsigned long *into)
{
  register unsigned long *from, *endp;

  from = ctx->KnL, endp = &ctx->KnL[32];
  while (from < endp)
    *into++ = *from++;
  return;
}

void
usekey (DESContext * ctx, register unsigned long *from)
{
  register unsigned long *to, *endp;

  to = ctx->KnL, endp = &ctx->KnL[32];
  while (to < endp)
    *to++ = *from++;
  return;
}

void
des (DESContext * ctx, unsigned char *inblock, unsigned char *outblock)
{
  unsigned long work[2];

  scrunch (inblock, work);
  desfunc (work, ctx->KnL);
  unscrun (work, outblock);
  return;
}

static void
scrunch (register unsigned char *outof, register unsigned long *into)
{
  *into = (*outof++ & 0xffL) << 24;
  *into |= (*outof++ & 0xffL) << 16;
  *into |= (*outof++ & 0xffL) << 8;
  *into++ |= (*outof++ & 0xffL);
  *into = (*outof++ & 0xffL) << 24;
  *into |= (*outof++ & 0xffL) << 16;
  *into |= (*outof++ & 0xffL) << 8;
  *into |= (*outof & 0xffL);
  return;
}

static void
unscrun (register unsigned long *outof, register unsigned char *into)
{
  *into++ = (*outof >> 24) & 0xffL;
  *into++ = (*outof >> 16) & 0xffL;
  *into++ = (*outof >> 8) & 0xffL;
  *into++ = *outof++ & 0xffL;
  *into++ = (*outof >> 24) & 0xffL;
  *into++ = (*outof >> 16) & 0xffL;
  *into++ = (*outof >> 8) & 0xffL;
  *into = *outof & 0xffL;
  return;
}

static const unsigned long SP1[64] = {
  0x01010400L, 0x00000000L, 0x00010000L, 0x01010404L,
  0x01010004L, 0x00010404L, 0x00000004L, 0x00010000L,
  0x00000400L, 0x01010400L, 0x01010404L, 0x00000400L,
  0x01000404L, 0x01010004L, 0x01000000L, 0x00000004L,
  0x00000404L, 0x01000400L, 0x01000400L, 0x00010400L,
  0x00010400L, 0x01010000L, 0x01010000L, 0x01000404L,
  0x00010004L, 0x01000004L, 0x01000004L, 0x00010004L,
  0x00000000L, 0x00000404L, 0x00010404L, 0x01000000L,
  0x00010000L, 0x01010404L, 0x00000004L, 0x01010000L,
  0x01010400L, 0x01000000L, 0x01000000L, 0x00000400L,
  0x01010004L, 0x00010000L, 0x00010400L, 0x01000004L,
  0x00000400L, 0x00000004L, 0x01000404L, 0x00010404L,
  0x01010404L, 0x00010004L, 0x01010000L, 0x01000404L,
  0x01000004L, 0x00000404L, 0x00010404L, 0x01010400L,
  0x00000404L, 0x01000400L, 0x01000400L, 0x00000000L,
  0x00010004L, 0x00010400L, 0x00000000L, 0x01010004L
};

static const unsigned long SP2[64] = {
  0x80108020L, 0x80008000L, 0x00008000L, 0x00108020L,
  0x00100000L, 0x00000020L, 0x80100020L, 0x80008020L,
  0x80000020L, 0x80108020L, 0x80108000L, 0x80000000L,
  0x80008000L, 0x00100000L, 0x00000020L, 0x80100020L,
  0x00108000L, 0x00100020L, 0x80008020L, 0x00000000L,
  0x80000000L, 0x00008000L, 0x00108020L, 0x80100000L,
  0x00100020L, 0x80000020L, 0x00000000L, 0x00108000L,
  0x00008020L, 0x80108000L, 0x80100000L, 0x00008020L,
  0x00000000L, 0x00108020L, 0x80100020L, 0x00100000L,
  0x80008020L, 0x80100000L, 0x80108000L, 0x00008000L,
  0x80100000L, 0x80008000L, 0x00000020L, 0x80108020L,
  0x00108020L, 0x00000020L, 0x00008000L, 0x80000000L,
  0x00008020L, 0x80108000L, 0x00100000L, 0x80000020L,
  0x00100020L, 0x80008020L, 0x80000020L, 0x00100020L,
  0x00108000L, 0x00000000L, 0x80008000L, 0x00008020L,
  0x80000000L, 0x80100020L, 0x80108020L, 0x00108000L
};

static const unsigned long SP3[64] = {
  0x00000208L, 0x08020200L, 0x00000000L, 0x08020008L,
  0x08000200L, 0x00000000L, 0x00020208L, 0x08000200L,
  0x00020008L, 0x08000008L, 0x08000008L, 0x00020000L,
  0x08020208L, 0x00020008L, 0x08020000L, 0x00000208L,
  0x08000000L, 0x00000008L, 0x08020200L, 0x00000200L,
  0x00020200L, 0x08020000L, 0x08020008L, 0x00020208L,
  0x08000208L, 0x00020200L, 0x00020000L, 0x08000208L,
  0x00000008L, 0x08020208L, 0x00000200L, 0x08000000L,
  0x08020200L, 0x08000000L, 0x00020008L, 0x00000208L,
  0x00020000L, 0x08020200L, 0x08000200L, 0x00000000L,
  0x00000200L, 0x00020008L, 0x08020208L, 0x08000200L,
  0x08000008L, 0x00000200L, 0x00000000L, 0x08020008L,
  0x08000208L, 0x00020000L, 0x08000000L, 0x08020208L,
  0x00000008L, 0x00020208L, 0x00020200L, 0x08000008L,
  0x08020000L, 0x08000208L, 0x00000208L, 0x08020000L,
  0x00020208L, 0x00000008L, 0x08020008L, 0x00020200L
};

static const unsigned long SP4[64] = {
  0x00802001L, 0x00002081L, 0x00002081L, 0x00000080L,
  0x00802080L, 0x00800081L, 0x00800001L, 0x00002001L,
  0x00000000L, 0x00802000L, 0x00802000L, 0x00802081L,
  0x00000081L, 0x00000000L, 0x00800080L, 0x00800001L,
  0x00000001L, 0x00002000L, 0x00800000L, 0x00802001L,
  0x00000080L, 0x00800000L, 0x00002001L, 0x00002080L,
  0x00800081L, 0x00000001L, 0x00002080L, 0x00800080L,
  0x00002000L, 0x00802080L, 0x00802081L, 0x00000081L,
  0x00800080L, 0x00800001L, 0x00802000L, 0x00802081L,
  0x00000081L, 0x00000000L, 0x00000000L, 0x00802000L,
  0x00002080L, 0x00800080L, 0x00800081L, 0x00000001L,
  0x00802001L, 0x00002081L, 0x00002081L, 0x00000080L,
  0x00802081L, 0x00000081L, 0x00000001L, 0x00002000L,
  0x00800001L, 0x00002001L, 0x00802080L, 0x00800081L,
  0x00002001L, 0x00002080L, 0x00800000L, 0x00802001L,
  0x00000080L, 0x00800000L, 0x00002000L, 0x00802080L
};

static const unsigned long SP5[64] = {
  0x00000100L, 0x02080100L, 0x02080000L, 0x42000100L,
  0x00080000L, 0x00000100L, 0x40000000L, 0x02080000L,
  0x40080100L, 0x00080000L, 0x02000100L, 0x40080100L,
  0x42000100L, 0x42080000L, 0x00080100L, 0x40000000L,
  0x02000000L, 0x40080000L, 0x40080000L, 0x00000000L,
  0x40000100L, 0x42080100L, 0x42080100L, 0x02000100L,
  0x42080000L, 0x40000100L, 0x00000000L, 0x42000000L,
  0x02080100L, 0x02000000L, 0x42000000L, 0x00080100L,
  0x00080000L, 0x42000100L, 0x00000100L, 0x02000000L,
  0x40000000L, 0x02080000L, 0x42000100L, 0x40080100L,
  0x02000100L, 0x40000000L, 0x42080000L, 0x02080100L,
  0x40080100L, 0x00000100L, 0x02000000L, 0x42080000L,
  0x42080100L, 0x00080100L, 0x42000000L, 0x42080100L,
  0x02080000L, 0x00000000L, 0x40080000L, 0x42000000L,
  0x00080100L, 0x02000100L, 0x40000100L, 0x00080000L,
  0x00000000L, 0x40080000L, 0x02080100L, 0x40000100L
};

static const unsigned long SP6[64] = {
  0x20000010L, 0x20400000L, 0x00004000L, 0x20404010L,
  0x20400000L, 0x00000010L, 0x20404010L, 0x00400000L,
  0x20004000L, 0x00404010L, 0x00400000L, 0x20000010L,
  0x00400010L, 0x20004000L, 0x20000000L, 0x00004010L,
  0x00000000L, 0x00400010L, 0x20004010L, 0x00004000L,
  0x00404000L, 0x20004010L, 0x00000010L, 0x20400010L,
  0x20400010L, 0x00000000L, 0x00404010L, 0x20404000L,
  0x00004010L, 0x00404000L, 0x20404000L, 0x20000000L,
  0x20004000L, 0x00000010L, 0x20400010L, 0x00404000L,
  0x20404010L, 0x00400000L, 0x00004010L, 0x20000010L,
  0x00400000L, 0x20004000L, 0x20000000L, 0x00004010L,
  0x20000010L, 0x20404010L, 0x00404000L, 0x20400000L,
  0x00404010L, 0x20404000L, 0x00000000L, 0x20400010L,
  0x00000010L, 0x00004000L, 0x20400000L, 0x00404010L,
  0x00004000L, 0x00400010L, 0x20004010L, 0x00000000L,
  0x20404000L, 0x20000000L, 0x00400010L, 0x20004010L
};

static const unsigned long SP7[64] = {
  0x00200000L, 0x04200002L, 0x04000802L, 0x00000000L,
  0x00000800L, 0x04000802L, 0x00200802L, 0x04200800L,
  0x04200802L, 0x00200000L, 0x00000000L, 0x04000002L,
  0x00000002L, 0x04000000L, 0x04200002L, 0x00000802L,
  0x04000800L, 0x00200802L, 0x00200002L, 0x04000800L,
  0x04000002L, 0x04200000L, 0x04200800L, 0x00200002L,
  0x04200000L, 0x00000800L, 0x00000802L, 0x04200802L,
  0x00200800L, 0x00000002L, 0x04000000L, 0x00200800L,
  0x04000000L, 0x00200800L, 0x00200000L, 0x04000802L,
  0x04000802L, 0x04200002L, 0x04200002L, 0x00000002L,
  0x00200002L, 0x04000000L, 0x04000800L, 0x00200000L,
  0x04200800L, 0x00000802L, 0x00200802L, 0x04200800L,
  0x00000802L, 0x04000002L, 0x04200802L, 0x04200000L,
  0x00200800L, 0x00000000L, 0x00000002L, 0x04200802L,
  0x00000000L, 0x00200802L, 0x04200000L, 0x00000800L,
  0x04000002L, 0x04000800L, 0x00000800L, 0x00200002L
};

static const unsigned long SP8[64] = {
  0x10001040L, 0x00001000L, 0x00040000L, 0x10041040L,
  0x10000000L, 0x10001040L, 0x00000040L, 0x10000000L,
  0x00040040L, 0x10040000L, 0x10041040L, 0x00041000L,
  0x10041000L, 0x00041040L, 0x00001000L, 0x00000040L,
  0x10040000L, 0x10000040L, 0x10001000L, 0x00001040L,
  0x00041000L, 0x00040040L, 0x10040040L, 0x10041000L,
  0x00001040L, 0x00000000L, 0x00000000L, 0x10040040L,
  0x10000040L, 0x10001000L, 0x00041040L, 0x00040000L,
  0x00041040L, 0x00040000L, 0x10041000L, 0x00001000L,
  0x00000040L, 0x10040040L, 0x00001000L, 0x00041040L,
  0x10001000L, 0x00000040L, 0x10000040L, 0x10040000L,
  0x10040040L, 0x10000000L, 0x00040000L, 0x10001040L,
  0x00000000L, 0x10041040L, 0x00040040L, 0x10000040L,
  0x10040000L, 0x10001000L, 0x10001040L, 0x00000000L,
  0x10041040L, 0x00041000L, 0x00041000L, 0x00001040L,
  0x00001040L, 0x00040040L, 0x10000000L, 0x10041000L
};

static void
desfunc (register unsigned long *block, register unsigned long *keys)
{
  register unsigned long fval, work, right, leftt;
  register int32_t round;

  leftt = block[0];
  right = block[1];
  work = ((leftt >> 4) ^ right) & 0x0f0f0f0fL;
  right ^= work;
  leftt ^= (work << 4);
  work = ((leftt >> 16) ^ right) & 0x0000ffffL;
  right ^= work;
  leftt ^= (work << 16);
  work = ((right >> 2) ^ leftt) & 0x33333333L;
  leftt ^= work;
  right ^= (work << 2);
  work = ((right >> 8) ^ leftt) & 0x00ff00ffL;
  leftt ^= work;
  right ^= (work << 8);
  right = ((right << 1) | ((right >> 31) & 1L)) & 0xffffffffL;
  work = (leftt ^ right) & 0xaaaaaaaaL;
  leftt ^= work;
  right ^= work;
  leftt = ((leftt << 1) | ((leftt >> 31) & 1L)) & 0xffffffffL;

  for (round = 0; round < 8; round++) {
    work = (right << 28) | (right >> 4);
    work ^= *keys++;
    fval = SP7[work & 0x3fL];
    fval |= SP5[(work >> 8) & 0x3fL];
    fval |= SP3[(work >> 16) & 0x3fL];
    fval |= SP1[(work >> 24) & 0x3fL];
    work = right ^ *keys++;
    fval |= SP8[work & 0x3fL];
    fval |= SP6[(work >> 8) & 0x3fL];
    fval |= SP4[(work >> 16) & 0x3fL];
    fval |= SP2[(work >> 24) & 0x3fL];
    leftt ^= fval;
    work = (leftt << 28) | (leftt >> 4);
    work ^= *keys++;
    fval = SP7[work & 0x3fL];
    fval |= SP5[(work >> 8) & 0x3fL];
    fval |= SP3[(work >> 16) & 0x3fL];
    fval |= SP1[(work >> 24) & 0x3fL];
    work = leftt ^ *keys++;
    fval |= SP8[work & 0x3fL];
    fval |= SP6[(work >> 8) & 0x3fL];
    fval |= SP4[(work >> 16) & 0x3fL];
    fval |= SP2[(work >> 24) & 0x3fL];
    right ^= fval;
  }

  right = (right << 31) | (right >> 1);
  work = (leftt ^ right) & 0xaaaaaaaaL;
  leftt ^= work;
  right ^= work;
  leftt = (leftt << 31) | (leftt >> 1);
  work = ((leftt >> 8) ^ right) & 0x00ff00ffL;
  right ^= work;
  leftt ^= (work << 8);
  work = ((leftt >> 2) ^ right) & 0x33333333L;
  right ^= work;
  leftt ^= (work << 2);
  work = ((right >> 16) ^ leftt) & 0x0000ffffL;
  leftt ^= work;
  right ^= (work << 16);
  work = ((right >> 4) ^ leftt) & 0x0f0f0f0fL;
  leftt ^= work;
  right ^= (work << 4);
  *block++ = right;
  *block = leftt;
  return;
}

/* Validation sets:
 *
 * Single-length key, single-length plaintext -
 * Key	  : 0123 4567 89ab cdef
 * Plain  : 0123 4567 89ab cde7
 * Cipher : c957 4425 6a5e d31d
 *
 * Double-length key, single-length plaintext -
 * Key	  : 0123 4567 89ab cdef fedc ba98 7654 3210
 * Plain  : 0123 4567 89ab cde7
 * Cipher : 7f1d 0a77 826b 8aff
 *
 * Double-length key, double-length plaintext -
 * Key	  : 0123 4567 89ab cdef fedc ba98 7654 3210
 * Plain  : 0123 4567 89ab cdef 0123 4567 89ab cdff
 * Cipher : 27a0 8440 406a df60 278f 47cf 42d6 15d7
 *
 * Triple-length key, single-length plaintext -
 * Key	  : 0123 4567 89ab cdef fedc ba98 7654 3210 89ab cdef 0123 4567
 * Plain  : 0123 4567 89ab cde7
 * Cipher : de0b 7c06 ae5e 0ed5
 *
 * Triple-length key, double-length plaintext -
 * Key	  : 0123 4567 89ab cdef fedc ba98 7654 3210 89ab cdef 0123 4567
 * Plain  : 0123 4567 89ab cdef 0123 4567 89ab cdff
 * Cipher : ad0d 1b30 ac17 cf07 0ed1 1c63 81e4 4de5
 *
 * d3des V5.0a rwo 9208.07 18:44 Graven Imagery
 **********************************************************************/