/* Copyright (C) 2000-2004 Peter Selinger.
   This file is part of ccrypt. It is free software and it is covered
   by the GNU general public license. See the file COPYING for details. */

/* $Id: unixcrypt3.c,v 1.4 2003/03/30 00:38:29 selinger Exp $ */
/* A drop-in replacement for crypt(3), where it is not available as a
   library function. Derived from GNU sources and specialized. */

/*
 * UFC-crypt: ultra fast crypt(3) implementation
 *
 * Copyright (C) 1991, 1992, 1993, 1996, 1997 Free Software Foundation, Inc.
 *
 * This library is free software; you can redistribute it and/or
 * modify it under the terms of the GNU Library General Public
 * License as published by the Free Software Foundation; either
 * version 2 of the License, or (at your option) any later version.
 *
 * This library 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.  See the GNU
 * Library General Public License for more details.
 *
 * You should have received a copy of the GNU Library General Public
 * License along with this library; see the file COPYING.LIB.  If not,
 * write to the Free Software Foundation, Inc., 59 Temple Place - Suite 330,
 * Boston, MA 02111-1307, USA.
 * */

#include <string.h>

/* define integer sizes */
#ifdef HAVE_STDINT_H
  #include <stdint.h>
  typedef uint_fast32_t ufc_long;
  typedef uint32_t long32;
#else
  /* hope for the best */
  typedef unsigned long int ufc_long;
  typedef unsigned int long32;
#endif

/* Reentrant functions use additional argument which
   points to a structure where the results are placed in.  */
struct crypt_data
{
  char keysched[16 * 8];
  char sb0[32768];
  char sb1[32768];
  char sb2[32768];
  char sb3[32768];
  /* end-of-aligment-critical-data */
  char crypt_3_buf[14];
  char current_salt[2];
  long int current_saltbits;
  int  direction, initialized;
};

/*
 * Permutation done once on the 56 bit
 *  key derived from the original 8 byte ASCII key.
 */
static const int pc1[56] = {
  57, 49, 41, 33, 25, 17,  9,  1, 58, 50, 42, 34, 26, 18,
  10,  2, 59, 51, 43, 35, 27, 19, 11,  3, 60, 52, 44, 36,
  63, 55, 47, 39, 31, 23, 15,  7, 62, 54, 46, 38, 30, 22,
  14,  6, 61, 53, 45, 37, 29, 21, 13,  5, 28, 20, 12,  4
};

/*
 * How much to rotate each 28 bit half of the pc1 permutated
 *  56 bit key before using pc2 to give the i' key
 */
static const int rots[16] = {
  1, 1, 2, 2, 2, 2, 2, 2, 1, 2, 2, 2, 2, 2, 2, 1
};

/*
 * Permutation giving the key
 * of the i' DES round
 */
static const int pc2[48] = {
  14, 17, 11, 24,  1,  5,  3, 28, 15,  6, 21, 10,
  23, 19, 12,  4, 26,  8, 16,  7, 27, 20, 13,  2,
  41, 52, 31, 37, 47, 55, 30, 40, 51, 45, 33, 48,
  44, 49, 39, 56, 34, 53, 46, 42, 50, 36, 29, 32
};

/*
 * The E expansion table which selects
 * bits from the 32 bit intermediate result.
 */
static const int esel[48] = {
  32,  1,  2,  3,  4,  5,  4,  5,  6,  7,  8,  9,
   8,  9, 10, 11, 12, 13, 12, 13, 14, 15, 16, 17,
  16, 17, 18, 19, 20, 21, 20, 21, 22, 23, 24, 25,
  24, 25, 26, 27, 28, 29, 28, 29, 30, 31, 32,  1
};

/*
 * Permutation done on the
 * result of sbox lookups
 */
static const int perm32[32] = {
  16,  7, 20, 21, 29, 12, 28, 17,  1, 15, 23, 26,  5, 18, 31, 10,
  2,   8, 24, 14, 32, 27,  3,  9, 19, 13, 30,  6, 22, 11,  4, 25
};

/*
 * The sboxes
 */
static const int sbox[8][4][16]= {
        { { 14,  4, 13,  1,  2, 15, 11,  8,  3, 10,  6, 12,  5,  9,  0,  7 },
          {  0, 15,  7,  4, 14,  2, 13,  1, 10,  6, 12, 11,  9,  5,  3,  8 },
          {  4,  1, 14,  8, 13,  6,  2, 11, 15, 12,  9,  7,  3, 10,  5,  0 },
          { 15, 12,  8,  2,  4,  9,  1,  7,  5, 11,  3, 14, 10,  0,  6, 13 }
        },

        { { 15,  1,  8, 14,  6, 11,  3,  4,  9,  7,  2, 13, 12,  0,  5, 10 },
          {  3, 13,  4,  7, 15,  2,  8, 14, 12,  0,  1, 10,  6,  9, 11,  5 },
          {  0, 14,  7, 11, 10,  4, 13,  1,  5,  8, 12,  6,  9,  3,  2, 15 },
          { 13,  8, 10,  1,  3, 15,  4,  2, 11,  6,  7, 12,  0,  5, 14,  9 }
        },

        { { 10,  0,  9, 14,  6,  3, 15,  5,  1, 13, 12,  7, 11,  4,  2,  8 },
          { 13,  7,  0,  9,  3,  4,  6, 10,  2,  8,  5, 14, 12, 11, 15,  1 },
          { 13,  6,  4,  9,  8, 15,  3,  0, 11,  1,  2, 12,  5, 10, 14,  7 },
          {  1, 10, 13,  0,  6,  9,  8,  7,  4, 15, 14,  3, 11,  5,  2, 12 }
        },

        { {  7, 13, 14,  3,  0,  6,  9, 10,  1,  2,  8,  5, 11, 12,  4, 15 },
          { 13,  8, 11,  5,  6, 15,  0,  3,  4,  7,  2, 12,  1, 10, 14,  9 },
          { 10,  6,  9,  0, 12, 11,  7, 13, 15,  1,  3, 14,  5,  2,  8,  4 },
          {  3, 15,  0,  6, 10,  1, 13,  8,  9,  4,  5, 11, 12,  7,  2, 14 }
        },

        { {  2, 12,  4,  1,  7, 10, 11,  6,  8,  5,  3, 15, 13,  0, 14,  9 },
          { 14, 11,  2, 12,  4,  7, 13,  1,  5,  0, 15, 10,  3,  9,  8,  6 },
          {  4,  2,  1, 11, 10, 13,  7,  8, 15,  9, 12,  5,  6,  3,  0, 14 },
          { 11,  8, 12,  7,  1, 14,  2, 13,  6, 15,  0,  9, 10,  4,  5,  3 }
        },

        { { 12,  1, 10, 15,  9,  2,  6,  8,  0, 13,  3,  4, 14,  7,  5, 11 },
          { 10, 15,  4,  2,  7, 12,  9,  5,  6,  1, 13, 14,  0, 11,  3,  8 },
          {  9, 14, 15,  5,  2,  8, 12,  3,  7,  0,  4, 10,  1, 13, 11,  6 },
          {  4,  3,  2, 12,  9,  5, 15, 10, 11, 14,  1,  7,  6,  0,  8, 13 }
        },

        { {  4, 11,  2, 14, 15,  0,  8, 13,  3, 12,  9,  7,  5, 10,  6,  1 },
          { 13,  0, 11,  7,  4,  9,  1, 10, 14,  3,  5, 12,  2, 15,  8,  6 },
          {  1,  4, 11, 13, 12,  3,  7, 14, 10, 15,  6,  8,  0,  5,  9,  2 },
          {  6, 11, 13,  8,  1,  4, 10,  7,  9,  5,  0, 15, 14,  2,  3, 12 }
        },

        { { 13,  2,  8,  4,  6, 15, 11,  1, 10,  9,  3, 14,  5,  0, 12,  7 },
          {  1, 15, 13,  8, 10,  3,  7,  4, 12,  5,  6, 11,  0, 14,  9,  2 },
          {  7, 11,  4,  1,  9, 12, 14,  2,  0,  6, 10, 13, 15,  3,  5,  8 },
          {  2,  1, 14,  7,  4, 10,  8, 13, 15, 12,  9,  0,  3,  5,  6, 11 }
        }
};

/*
 * This is the initial
 * permutation matrix
 */
static const int initial_perm[64] = {
  58, 50, 42, 34, 26, 18, 10,  2, 60, 52, 44, 36, 28, 20, 12, 4,
  62, 54, 46, 38, 30, 22, 14,  6, 64, 56, 48, 40, 32, 24, 16, 8,
  57, 49, 41, 33, 25, 17,  9,  1, 59, 51, 43, 35, 27, 19, 11, 3,
  61, 53, 45, 37, 29, 21, 13,  5, 63, 55, 47, 39, 31, 23, 15, 7
};

/*
 * This is the final
 * permutation matrix
 */
static const int final_perm[64] = {
  40,  8, 48, 16, 56, 24, 64, 32, 39,  7, 47, 15, 55, 23, 63, 31,
  38,  6, 46, 14, 54, 22, 62, 30, 37,  5, 45, 13, 53, 21, 61, 29,
  36,  4, 44, 12, 52, 20, 60, 28, 35,  3, 43, 11, 51, 19, 59, 27,
  34,  2, 42, 10, 50, 18, 58, 26, 33,  1, 41,  9, 49, 17, 57, 25
};

#define ascii_to_bin(c) ((c)>='a'?(c-59):(c)>='A'?((c)-53):(c)-'.')
#define bin_to_ascii(c) ((c)>=38?((c)-38+'a'):(c)>=12?((c)-12+'A'):(c)+'.')

static const ufc_long BITMASK[24] = {
  0x40000000, 0x20000000, 0x10000000, 0x08000000, 0x04000000, 0x02000000,
  0x01000000, 0x00800000, 0x00400000, 0x00200000, 0x00100000, 0x00080000,
  0x00004000, 0x00002000, 0x00001000, 0x00000800, 0x00000400, 0x00000200,
  0x00000100, 0x00000080, 0x00000040, 0x00000020, 0x00000010, 0x00000008
};

static const unsigned char bytemask[8]  = {
  0x80, 0x40, 0x20, 0x10, 0x08, 0x04, 0x02, 0x01
};

static const ufc_long longmask[32] = {
  0x80000000, 0x40000000, 0x20000000, 0x10000000,
  0x08000000, 0x04000000, 0x02000000, 0x01000000,
  0x00800000, 0x00400000, 0x00200000, 0x00100000,
  0x00080000, 0x00040000, 0x00020000, 0x00010000,
  0x00008000, 0x00004000, 0x00002000, 0x00001000,
  0x00000800, 0x00000400, 0x00000200, 0x00000100,
  0x00000080, 0x00000040, 0x00000020, 0x00000010,
  0x00000008, 0x00000004, 0x00000002, 0x00000001
};

/*
 * do_pc1: permform pc1 permutation in the key schedule generation.
 *
 * The first   index is the byte number in the 8 byte ASCII key
 *  -  second    -      -    the two 28 bits halfs of the result
 *  -  third     -   selects the 7 bits actually used of each byte
 *
 * The result is kept with 28 bit per 32 bit with the 4 most significant
 * bits zero.
 */
static ufc_long do_pc1[8][2][128];

/*
 * do_pc2: permform pc2 permutation in the key schedule generation.
 *
 * The first   index is the septet number in the two 28 bit intermediate values
 *  -  second    -    -  -  septet values
 *
 * Knowledge of the structure of the pc2 permutation is used.
 *
 * The result is kept with 28 bit per 32 bit with the 4 most significant
 * bits zero.
 */
static ufc_long do_pc2[8][128];

/*
 * eperm32tab: do 32 bit permutation and E selection
 *
 * The first index is the byte number in the 32 bit value to be permuted
 *  -  second  -   is the value of this byte
 *  -  third   -   selects the two 32 bit values
 *
 * The table is used and generated internally in init_des to speed it up
 */
static ufc_long eperm32tab[4][256][2];

/*
 * efp: undo an extra e selection and do final
 *      permutation giving the DES result.
 *
 *      Invoked 6 bit a time on two 48 bit values
 *      giving two 32 bit longs.
 */
static ufc_long efp[16][64][2];

/* lookup a 6 bit value in sbox */

#define s_lookup(i,s) sbox[(i)][(((s)>>4) & 0x2)|((s) & 0x1)][((s)>>1) & 0xf];

#define SBA(sb, v) (*(long32*)((char*)(sb)+(v)))

static void 
_ufc_doit_r(itr, __data, res)
     ufc_long itr, *res;
     struct crypt_data *__data;
{
  int i;
  long32 s, *k;
  long32 *sb01 = (long32*)__data->sb0;
  long32 *sb23 = (long32*)__data->sb2;
  long32 l1, l2, r1, r2;

  l1 = (long32)res[0]; l2 = (long32)res[1];
  r1 = (long32)res[2]; r2 = (long32)res[3];

  while(itr--) {
    k = (long32*)__data->keysched;
    for(i=8; i--; ) {
      s = *k++ ^ r1;
      l1 ^= SBA(sb01, s & 0xffff); l2 ^= SBA(sb01, (s & 0xffff)+4);
      l1 ^= SBA(sb01, s >>= 16  ); l2 ^= SBA(sb01, (s         )+4);
      s = *k++ ^ r2;
      l1 ^= SBA(sb23, s & 0xffff); l2 ^= SBA(sb23, (s & 0xffff)+4);
      l1 ^= SBA(sb23, s >>= 16  ); l2 ^= SBA(sb23, (s         )+4);

      s = *k++ ^ l1;
      r1 ^= SBA(sb01, s & 0xffff); r2 ^= SBA(sb01, (s & 0xffff)+4);
      r1 ^= SBA(sb01, s >>= 16  ); r2 ^= SBA(sb01, (s         )+4);
      s = *k++ ^ l2;
      r1 ^= SBA(sb23, s & 0xffff); r2 ^= SBA(sb23, (s & 0xffff)+4);
      r1 ^= SBA(sb23, s >>= 16  ); r2 ^= SBA(sb23, (s         )+4);
    }
    s=l1; l1=r1; r1=s; s=l2; l2=r2; r2=s;
  }
  res[0] = l1; res[1] = l2; res[2] = r1; res[3] = r2;
}

/*
 * Initialize unit - may be invoked directly
 * by fcrypt users.
 */

static void
__init_des_r(__data)
     struct crypt_data *__data;
{
  int comes_from_bit;
  int bit, sg;
  ufc_long j;
  ufc_long mask1, mask2;
  int e_inverse[64];
  static volatile int small_tables_initialized = 0;

  long32 *sb[4];
  sb[0] = (long32*)__data->sb0; sb[1] = (long32*)__data->sb1;
  sb[2] = (long32*)__data->sb2; sb[3] = (long32*)__data->sb3;

  if(small_tables_initialized == 0) {

    /*
     * Create the do_pc1 table used
     * to affect pc1 permutation
     * when generating keys
     */
    memset((char*)do_pc1, 0, (int)sizeof(do_pc1));
    for(bit = 0; bit < 56; bit++) {
      comes_from_bit  = pc1[bit] - 1;
      mask1 = bytemask[comes_from_bit % 8 + 1];
      mask2 = longmask[bit % 28 + 4];
      for(j = 0; j < 128; j++) {
	if(j & mask1)
	  do_pc1[comes_from_bit / 8][bit / 28][j] |= mask2;
      }
    }

    /*
     * Create the do_pc2 table used
     * to affect pc2 permutation when
     * generating keys
     */
    memset((char*)do_pc2, 0, (int)sizeof(do_pc2));
    for(bit = 0; bit < 48; bit++) {
      comes_from_bit  = pc2[bit] - 1;
      mask1 = bytemask[comes_from_bit % 7 + 1];
      mask2 = BITMASK[bit % 24];
      for(j = 0; j < 128; j++) {
	if(j & mask1)
	  do_pc2[comes_from_bit / 7][j] |= mask2;
      }
    }

    /*
     * Now generate the table used to do combined
     * 32 bit permutation and e expansion
     *
     * We use it because we have to permute 16384 32 bit
     * longs into 48 bit in order to initialize sb.
     *
     * Looping 48 rounds per permutation becomes
     * just too slow...
     *
     */

    memset((char*)eperm32tab, 0, (int)sizeof(eperm32tab));
    for(bit = 0; bit < 48; bit++) {
      ufc_long mask1,comes_from;
      comes_from = perm32[esel[bit]-1]-1;
      mask1      = bytemask[comes_from % 8];
      for(j = 256; j--;) {
	if(j & mask1)
	  eperm32tab[comes_from / 8][j][bit / 24] |= BITMASK[bit % 24];
      }
    }

    /*
     * Create an inverse matrix for esel telling
     * where to plug out bits if undoing it
     */
    for(bit=48; bit--;) {
      e_inverse[esel[bit] - 1     ] = bit;
      e_inverse[esel[bit] - 1 + 32] = bit + 48;
    }

    /*
     * create efp: the matrix used to
     * undo the E expansion and effect final permutation
     */
    memset((char*)efp, 0, (int)sizeof efp);
    for(bit = 0; bit < 64; bit++) {
      int o_bit, o_long;
      ufc_long word_value, mask1, mask2;
      int comes_from_f_bit, comes_from_e_bit;
      int comes_from_word, bit_within_word;

      /* See where bit i belongs in the two 32 bit long's */
      o_long = bit / 32; /* 0..1  */
      o_bit  = bit % 32; /* 0..31 */

      /*
       * And find a bit in the e permutated value setting this bit.
       *
       * Note: the e selection may have selected the same bit several
       * times. By the initialization of e_inverse, we only look
       * for one specific instance.
       */
      comes_from_f_bit = final_perm[bit] - 1;         /* 0..63 */
      comes_from_e_bit = e_inverse[comes_from_f_bit]; /* 0..95 */
      comes_from_word  = comes_from_e_bit / 6;        /* 0..15 */
      bit_within_word  = comes_from_e_bit % 6;        /* 0..5  */

      mask1 = longmask[bit_within_word + 26];
      mask2 = longmask[o_bit];

      for(word_value = 64; word_value--;) {
	if(word_value & mask1)
	  efp[comes_from_word][word_value][o_long] |= mask2;
      }
    }
    small_tables_initialized = 1;
  }

  /*
   * Create the sb tables:
   *
   * For each 12 bit segment of an 48 bit intermediate
   * result, the sb table precomputes the two 4 bit
   * values of the sbox lookups done with the two 6
   * bit halves, shifts them to their proper place,
   * sends them through perm32 and finally E expands
   * them so that they are ready for the next
   * DES round.
   *
   */

  memset((char*)__data->sb0, 0, (int)sizeof(__data->sb0));
  memset((char*)__data->sb1, 0, (int)sizeof(__data->sb1));
  memset((char*)__data->sb2, 0, (int)sizeof(__data->sb2));
  memset((char*)__data->sb3, 0, (int)sizeof(__data->sb3));

  for(sg = 0; sg < 4; sg++) {
    int j1, j2;
    int s1, s2;

    for(j1 = 0; j1 < 64; j1++) {
      s1 = s_lookup(2 * sg, j1);
      for(j2 = 0; j2 < 64; j2++) {
	ufc_long to_permute, inx;

	s2         = s_lookup(2 * sg + 1, j2);
	to_permute = (((ufc_long)s1 << 4)  |
		      (ufc_long)s2) << (24 - 8 * (ufc_long)sg);

	inx = ((j1 << 6)  | j2) << 1;
	sb[sg][inx  ]  = eperm32tab[0][(to_permute >> 24) & 0xff][0];
	sb[sg][inx+1]  = eperm32tab[0][(to_permute >> 24) & 0xff][1];
	sb[sg][inx  ] |= eperm32tab[1][(to_permute >> 16) & 0xff][0];
	sb[sg][inx+1] |= eperm32tab[1][(to_permute >> 16) & 0xff][1];
	sb[sg][inx  ] |= eperm32tab[2][(to_permute >>  8) & 0xff][0];
	sb[sg][inx+1] |= eperm32tab[2][(to_permute >>  8) & 0xff][1];
	sb[sg][inx  ] |= eperm32tab[3][(to_permute)       & 0xff][0];
	sb[sg][inx+1] |= eperm32tab[3][(to_permute)       & 0xff][1];
      }
    }
  }

  __data->initialized++;
}

/*
 * Process the elements of the sb table permuting the
 * bits swapped in the expansion by the current salt.
 */

static void
shuffle_sb(k, saltbits)
     long32 *k;
     ufc_long saltbits;
{
  ufc_long j;
  long32 x;
  for(j=4096; j--;) {
    x = (k[0] ^ k[1]) & (long32)saltbits;
    *k++ ^= x;
    *k++ ^= x;
  }
}

/*
 * Setup the unit for a new salt
 * Hopefully we'll not see a new salt in each crypt call.
 */

static void
_ufc_setup_salt_r(s, __data)
     __const char *s;
     struct crypt_data *__data;
{
  ufc_long i, j, saltbits;

  if(__data->initialized == 0)
    __init_des_r(__data);

  if(s[0] == __data->current_salt[0] && s[1] == __data->current_salt[1])
    return;
  __data->current_salt[0] = s[0]; __data->current_salt[1] = s[1];

  /*
   * This is the only crypt change to DES:
   * entries are swapped in the expansion table
   * according to the bits set in the salt.
   */
  saltbits = 0;
  for(i = 0; i < 2; i++) {
    long c=ascii_to_bin(s[i]);
    for(j = 0; j < 6; j++) {
      if((c >> j) & 0x1)
	saltbits |= BITMASK[6 * i + j];
    }
  }

  /*
   * Permute the sb table values
   * to reflect the changed e
   * selection table
   */

  shuffle_sb((long32*)__data->sb0, __data->current_saltbits ^ saltbits);
  shuffle_sb((long32*)__data->sb1, __data->current_saltbits ^ saltbits);
  shuffle_sb((long32*)__data->sb2, __data->current_saltbits ^ saltbits);
  shuffle_sb((long32*)__data->sb3, __data->current_saltbits ^ saltbits);

  __data->current_saltbits = saltbits;
}

static void
_ufc_mk_keytab_r(key, __data)
     const char *key;
     struct crypt_data *__data;
{
  ufc_long v1, v2, *k1;
  int i;
  long32 v, *k2;
  k2 = (long32*)__data->keysched;

  v1 = v2 = 0; k1 = &do_pc1[0][0][0];
  for(i = 8; i--;) {
    v1 |= k1[*key   & 0x7f]; k1 += 128;
    v2 |= k1[*key++ & 0x7f]; k1 += 128;
  }

  for(i = 0; i < 16; i++) {
    k1 = &do_pc2[0][0];

    v1 = (v1 << rots[i]) | (v1 >> (28 - rots[i]));
    v  = k1[(v1 >> 21) & 0x7f]; k1 += 128;
    v |= k1[(v1 >> 14) & 0x7f]; k1 += 128;
    v |= k1[(v1 >>  7) & 0x7f]; k1 += 128;
    v |= k1[(v1      ) & 0x7f]; k1 += 128;

    *k2++ = (v | 0x00008000);
    v = 0;

    v2 = (v2 << rots[i]) | (v2 >> (28 - rots[i]));
    v |= k1[(v2 >> 21) & 0x7f]; k1 += 128;
    v |= k1[(v2 >> 14) & 0x7f]; k1 += 128;
    v |= k1[(v2 >>  7) & 0x7f]; k1 += 128;
    v |= k1[(v2      ) & 0x7f];

    *k2++ = (v | 0x00008000);
  }

  __data->direction = 0;
}

/*
 * Undo an extra E selection and do final permutations
 */

static void
_ufc_dofinalperm_r(res, __data)
     ufc_long *res;
     struct crypt_data *__data;
{
  ufc_long v1, v2, x;
  ufc_long l1,l2,r1,r2;

  l1 = res[0]; l2 = res[1];
  r1 = res[2]; r2 = res[3];

  x = (l1 ^ l2) & __data->current_saltbits; l1 ^= x; l2 ^= x;
  x = (r1 ^ r2) & __data->current_saltbits; r1 ^= x; r2 ^= x;

  v1=v2=0; l1 >>= 3; l2 >>= 3; r1 >>= 3; r2 >>= 3;

  v1 |= efp[15][ r2         & 0x3f][0]; v2 |= efp[15][ r2 & 0x3f][1];
  v1 |= efp[14][(r2 >>= 6)  & 0x3f][0]; v2 |= efp[14][ r2 & 0x3f][1];
  v1 |= efp[13][(r2 >>= 10) & 0x3f][0]; v2 |= efp[13][ r2 & 0x3f][1];
  v1 |= efp[12][(r2 >>= 6)  & 0x3f][0]; v2 |= efp[12][ r2 & 0x3f][1];

  v1 |= efp[11][ r1         & 0x3f][0]; v2 |= efp[11][ r1 & 0x3f][1];
  v1 |= efp[10][(r1 >>= 6)  & 0x3f][0]; v2 |= efp[10][ r1 & 0x3f][1];
  v1 |= efp[ 9][(r1 >>= 10) & 0x3f][0]; v2 |= efp[ 9][ r1 & 0x3f][1];
  v1 |= efp[ 8][(r1 >>= 6)  & 0x3f][0]; v2 |= efp[ 8][ r1 & 0x3f][1];

  v1 |= efp[ 7][ l2         & 0x3f][0]; v2 |= efp[ 7][ l2 & 0x3f][1];
  v1 |= efp[ 6][(l2 >>= 6)  & 0x3f][0]; v2 |= efp[ 6][ l2 & 0x3f][1];
  v1 |= efp[ 5][(l2 >>= 10) & 0x3f][0]; v2 |= efp[ 5][ l2 & 0x3f][1];
  v1 |= efp[ 4][(l2 >>= 6)  & 0x3f][0]; v2 |= efp[ 4][ l2 & 0x3f][1];

  v1 |= efp[ 3][ l1         & 0x3f][0]; v2 |= efp[ 3][ l1 & 0x3f][1];
  v1 |= efp[ 2][(l1 >>= 6)  & 0x3f][0]; v2 |= efp[ 2][ l1 & 0x3f][1];
  v1 |= efp[ 1][(l1 >>= 10) & 0x3f][0]; v2 |= efp[ 1][ l1 & 0x3f][1];
  v1 |= efp[ 0][(l1 >>= 6)  & 0x3f][0]; v2 |= efp[ 0][ l1 & 0x3f][1];

  res[0] = v1; res[1] = v2;
}

/*
 * crypt only: convert from 64 bit to 11 bit ASCII
 * prefixing with the salt
 */

static void
_ufc_output_conversion_r(v1, v2, salt, __data)
     ufc_long v1, v2;
     __const char *salt;
     struct crypt_data *__data;
{
  int i, s, shf;

  __data->crypt_3_buf[0] = salt[0];
  __data->crypt_3_buf[1] = salt[1] ? salt[1] : salt[0];

  for(i = 0; i < 5; i++) {
    shf = (26 - 6 * i); /* to cope with MSC compiler bug */
    __data->crypt_3_buf[i + 2] = bin_to_ascii((v1 >> shf) & 0x3f);
  }

  s  = (v2 & 0xf) << 2;
  v2 = (v2 >> 2) | ((v1 & 0x3) << 30);

  for(i = 5; i < 10; i++) {
    shf = (56 - 6 * i);
    __data->crypt_3_buf[i + 2] = bin_to_ascii((v2 >> shf) & 0x3f);
  }

  __data->crypt_3_buf[12] = bin_to_ascii(s);
  __data->crypt_3_buf[13] = 0;
}

/*
 * UNIX crypt function
 */

static char *crypt_r (const char *key, const char *salt, struct crypt_data *data)
{
  ufc_long res[4];
  char ktab[9];
  ufc_long xx = 25; /* to cope with GCC long long compiler bugs */

  /*
   * Hack DES tables according to salt
   */
  _ufc_setup_salt_r (salt, data);

  /*
   * Setup key schedule
   */
  memset (ktab, 0, (int) sizeof (ktab));
  (void) strncpy (ktab, key, 8);
  _ufc_mk_keytab_r (ktab, data);

  /*
   * Go for the 25 DES encryptions
   */
  memset ((char*) res, 0, (int) sizeof (res));
  _ufc_doit_r (xx,  data, &res[0]);

  /*
   * Do final permutations
   */
  _ufc_dofinalperm_r (res, data);

  /*
   * And convert back to 6 bit ASCII
   */
  _ufc_output_conversion_r (res[0], res[1], salt, data);

  return data->crypt_3_buf;
}

char *crypt_replacement (const char *key, const char *salt) 
{
  /* note: the following declaration is alignment critical. If we
     remove "static", it will not work properly. I'm not sure why
     not. */
  static struct crypt_data data;

  return crypt_r (key, salt, &data);
}