src/src/crypt16.c

   1 /*
   2  * Copyright (c) 2000-2002
   3  *   Chris Adams <cmadams@iruntheinter.net>
   4  *   written for HiWAAY Internet Services
   5  *
   6  * This program is free software; you can redistribute it and/or modify
   7  * it under the terms of the GNU General Public License as published by
   8  * the Free Software Foundation; either version 2 of the License, or
   9  * (at your option) any later version.
  10  *
  11  * This program is distributed in the hope that it will be useful,
  12  * but WITHOUT ANY WARRANTY; without even the implied warranty of
  13  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  14  * GNU General Public License for more details.
  15  *
  16  * You should have received a copy of the GNU General Public License
  17  * along with this program; if not, write to the Free Software
  18  * Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA  02111-1307
  19  * USA
  20  */
  21
  22 /*
  23  * Adapted for Exim by Tamas TEVESZ <ice@extreme.hu>
  24  * Further adapted by Philip Hazel to cut out this function for operating
  25  *   systems that have a built-in version.
  26  */
  27
  28 /* The OS has a built-in crypt16(). Some compilers don't like compiling empty
  29 modules, so keep them happy with a dummy when skipping the rest. */
  30
  31 #include "config.h"
  32
  33 #ifdef HAVE_CRYPT16
  34 static void dummy(int x) { dummy(x-1); }
  35 #else
  36
  37 /* The OS doesn't have a built-in crypt16(). Compile this one. */
  38
  39 #include <unistd.h>
  40 #include <string.h>
  41 #include "os.h"
  42
  43 #ifdef CRYPT_H
  44 #include <crypt.h>
  45 #endif
  46
  47 char *crypt16(char *key, char *salt)
  48 {
  49        static char res[25];
  50        static char s2[3];
  51        char *p;
  52
  53        /* Clear the string of any previous data */
  54        memset (res, 0, sizeof (res));
  55
  56        /* crypt the first part */
  57        p = crypt (key, salt);
  58        strncpy (res, p, 13);
  59
  60        if (strlen (key) > 8)
  61        {
  62                /* crypt the rest
  63                 * the first two characters of the first block (not counting
  64                 * the salt) make up the new salt */
  65                strncpy (s2, &(res[2]), 2);
  66                p = crypt (&(key[8]), s2);
  67                strncpy (&(res[13]), &(p[2]), 11);
  68                memset (s2, 0, sizeof (s2));
  69        }
  70
  71        return (res);
  72 }
  73 #endif
  74
  75 /* End of crypt16.c */