lib/libncp/ncpl_crypt.c

   1 /*
   2  *  Routines in this file based on the work of Volker Lendecke,
   3  *  Adapted for ncplib by Boris Popov
   4  *  Please note that ncpl_crypt.c file should be indentical to this one
   5  *
   6  * $FreeBSD: src/lib/libncp/ncpl_crypt.c,v 1.1 1999/10/12 11:56:39 bp Exp $
   7  * $DragonFly: src/lib/libncp/ncpl_crypt.c,v 1.2 2003/06/17 04:26:50 dillon Exp $
   8  */
   9 #include <sys/param.h>
  10 #include <sys/errno.h>
  11 #include <sys/malloc.h>
  12 #include <string.h>
  13
  14 /*$*********************************************************
  15    $*
  16    $* This code has been taken from DDJ 11/93, from an
  17    $* article by Pawel Szczerbina.
  18    $*
  19    $* Password encryption routines follow.
  20    $* Converted to C from Barry Nance's Pascal
  21    $* prog published in the March -93 issue of Byte.
  22    $*
  23    $* Adapted to be useable for ncpfs by
  24    $* Volker Lendecke <lendecke@namu01.gwdg.de> in
  25    $* October 1995.
  26    $*
  27    $********************************************************* */
  28
  29
  30
  31 typedef unsigned char buf32[32];
  32
  33 static unsigned char encrypttable[256] = {
  34 0x7, 0x8, 0x0, 0x8, 0x6, 0x4, 0xE, 0x4, 0x5, 0xC, 0x1, 0x7, 0xB, 0xF, 0xA, 0x8,
  35 0xF, 0x8, 0xC, 0xC, 0x9, 0x4, 0x1, 0xE, 0x4, 0x6, 0x2, 0x4, 0x0, 0xA, 0xB, 0x9,
  36 0x2, 0xF, 0xB, 0x1, 0xD, 0x2, 0x1, 0x9, 0x5, 0xE, 0x7, 0x0, 0x0, 0x2, 0x6, 0x6,
  37 0x0, 0x7, 0x3, 0x8, 0x2, 0x9, 0x3, 0xF, 0x7, 0xF, 0xC, 0xF, 0x6, 0x4, 0xA, 0x0,
  38 0x2, 0x3, 0xA, 0xB, 0xD, 0x8, 0x3, 0xA, 0x1, 0x7, 0xC, 0xF, 0x1, 0x8, 0x9, 0xD,
  39 0x9, 0x1, 0x9, 0x4, 0xE, 0x4, 0xC, 0x5, 0x5, 0xC, 0x8, 0xB, 0x2, 0x3, 0x9, 0xE,
  40 0x7, 0x7, 0x6, 0x9, 0xE, 0xF, 0xC, 0x8, 0xD, 0x1, 0xA, 0x6, 0xE, 0xD, 0x0, 0x7,
  41 0x7, 0xA, 0x0, 0x1, 0xF, 0x5, 0x4, 0xB, 0x7, 0xB, 0xE, 0xC, 0x9, 0x5, 0xD, 0x1,
  42 0xB, 0xD, 0x1, 0x3, 0x5, 0xD, 0xE, 0x6, 0x3, 0x0, 0xB, 0xB, 0xF, 0x3, 0x6, 0x4,
  43 0x9, 0xD, 0xA, 0x3, 0x1, 0x4, 0x9, 0x4, 0x8, 0x3, 0xB, 0xE, 0x5, 0x0, 0x5, 0x2,
  44 0xC, 0xB, 0xD, 0x5, 0xD, 0x5, 0xD, 0x2, 0xD, 0x9, 0xA, 0xC, 0xA, 0x0, 0xB, 0x3,
  45 0x5, 0x3, 0x6, 0x9, 0x5, 0x1, 0xE, 0xE, 0x0, 0xE, 0x8, 0x2, 0xD, 0x2, 0x2, 0x0,
  46 0x4, 0xF, 0x8, 0x5, 0x9, 0x6, 0x8, 0x6, 0xB, 0xA, 0xB, 0xF, 0x0, 0x7, 0x2, 0x8,
  47 0xC, 0x7, 0x3, 0xA, 0x1, 0x4, 0x2, 0x5, 0xF, 0x7, 0xA, 0xC, 0xE, 0x5, 0x9, 0x3,
  48 0xE, 0x7, 0x1, 0x2, 0xE, 0x1, 0xF, 0x4, 0xA, 0x6, 0xC, 0x6, 0xF, 0x4, 0x3, 0x0,
  49 0xC, 0x0, 0x3, 0x6, 0xF, 0x8, 0x7, 0xB, 0x2, 0xD, 0xC, 0x6, 0xA, 0xA, 0x8, 0xD
  50 };
  51
  52 static buf32 encryptkeys = {
  53     0x48, 0x93, 0x46, 0x67, 0x98, 0x3D, 0xE6, 0x8D,
  54     0xB7, 0x10, 0x7A, 0x26, 0x5A, 0xB9, 0xB1, 0x35,
  55     0x6B, 0x0F, 0xD5, 0x70, 0xAE, 0xFB, 0xAD, 0x11,
  56     0xF4, 0x47, 0xDC, 0xA7, 0xEC, 0xCF, 0x50, 0xC0
  57 };
  58
  59 /*
  60  * Create table-based 16-bytes hash from a 32-bytes array
  61  */
  62 static void
  63 nw_hash(buf32 temp, unsigned char *target) {
  64         short sum;
  65         unsigned char b3;
  66         int s, b2, i;
  67
  68         sum = 0;
  69
  70         for (b2 = 0; b2 <= 1; ++b2) {
  71                 for (s = 0; s <= 31; ++s) {
  72                         b3 = (temp[s] + sum) ^ (temp[(s + sum) & 31] - encryptkeys[s]);
  73                         sum += b3;
  74                         temp[s] = b3;
  75                 }
  76         }
  77
  78         for (i = 0; i <= 15; ++i) {
  79                 target[i] = encrypttable[temp[2 * i]]
  80                     | (encrypttable[temp[2 * i + 1]] << 4);
  81         }
  82 }
  83
  84
  85 /*
  86  * Create a 16-bytes pattern from given buffer based on a four bytes key
  87  */
  88 void
  89 nw_keyhash(const u_char *key, const u_char *buf, int buflen, u_char *target) {
  90         int b2, d, s;
  91         buf32 temp;
  92
  93         while (buflen > 0 && buf[buflen - 1] == 0)
  94                 buflen--;
  95
  96         bzero(temp, sizeof(temp));
  97
  98         d = 0;
  99         while (buflen >= 32) {
 100                 for (s = 0; s <= 31; ++s)
 101                         temp[s] ^= buf[d++];
 102                 buflen -= 32;
 103         }
 104         b2 = d;
 105         if (buflen > 0) {
 106                 for (s = 0; s <= 31; ++s) {
 107                         if (d + buflen == b2) {
 108                                 temp[s] ^= encryptkeys[s];
 109                                 b2 = d;
 110                         } else
 111                                 temp[s] ^= buf[b2++];
 112                 }
 113         }
 114         for (s = 0; s <= 31; ++s)
 115                 temp[s] ^= key[s & 3];
 116
 117         nw_hash(temp, target);
 118 }
 119
 120 /*
 121  * Create an 8-bytes pattern from an 8-bytes key and 16-bytes of data
 122  */
 123 void
 124 nw_encrypt(const u_char *fra, const u_char *buf, u_char *target) {
 125         buf32 k;
 126         int s;
 127
 128         nw_keyhash(fra, buf, 16, k);
 129         nw_keyhash(fra + 4, buf, 16, k + 16);
 130
 131         for (s = 0; s < 16; s++)
 132                 k[s] ^= k[31 - s];
 133
 134         for (s = 0; s < 8; s++)
 135                 *target++ = k[s] ^ k[15 - s];
 136 }
 137
 138