lib/realm.c

   1 /* realm.c      realm related functions
   2  * Copyright (C) 2002  Simon Josefsson
   3  *
   4  * This file is part of Shishi.
   5  *
   6  * Shishi 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  * Shishi 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 Shishi; if not, write to the Free Software
  18  * Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA  02111-1307  USA
  19  *
  20  */
  21
  22 #include "internal.h"
  23
  24 /**
  25  * shishi_realm_default_guess:
  26  *
  27  * Guesses a realm based on getdomainname() (which really is NIS/YP
  28  * domain, but if it is set it might be a good guess), or if it fails,
  29  * based on gethostname(), or if it fails, the string
  30  * "could-not-guess-default-realm". Note that the hostname is not
  31  * trimmed off of the data returned by gethostname() to get the domain
  32  * name and use that as the realm.
  33  *
  34  * Return value: Returns guessed realm for host as a string that has
  35  * to be deallocated with free() by the caller.
  36  **/
  37 char *
  38 shishi_realm_default_guess (void)
  39 {
  40   char buf[HOST_NAME_MAX];
  41   int ret;
  42
  43   ret = getdomainname (buf, sizeof (buf));
  44   buf[sizeof (buf) - 1] = '\0';
  45   if (ret != 0 || strlen (buf) == 0 || strcmp (buf, "(none)") == 0)
  46     {
  47       ret = gethostname (buf, sizeof (buf));
  48       buf[sizeof (buf) - 1] = '\0';
  49
  50       if (ret != 0)
  51         strcpy (buf, "could-not-guess-default-realm");
  52     }
  53
  54   return strdup (buf);
  55 }
  56
  57 /**
  58  * shishi_realm_default:
  59  * @handle: Shishi library handle create by shishi_init().
  60  *
  61  * Return value: Returns the default realm used in the library.  (Not
  62  * a copy of it, so don't modify or deallocate it.)
  63  **/
  64 const char *
  65 shishi_realm_default (Shishi * handle)
  66 {
  67   if (!handle->default_realm)
  68     {
  69       char *p;
  70       p = shishi_realm_default_guess ();
  71       shishi_realm_default_set (handle, p);
  72       free (p);
  73     }
  74
  75   return handle->default_realm;
  76 }
  77
  78 /**
  79  * shishi_realm_default_set:
  80  * @handle: Shishi library handle create by shishi_init().
  81  * @realm: string with new default realm name, or NULL to reset to default.
  82  *
  83  * Set the default realm used in the library.  The string is copied
  84  * into the library, so you can dispose of the variable immediately
  85  * after calling this function.
  86  **/
  87 void
  88 shishi_realm_default_set (Shishi * handle, const char *realm)
  89 {
  90   if (handle->default_realm)
  91     free (handle->default_realm);
  92   if (realm)
  93     handle->default_realm = strdup (realm);
  94   else
  95     handle->default_realm = NULL;
  96 }
  97
  98 const char *
  99 shishi_realm_for_server_file (Shishi * handle, char *server)
 100 {
 101   return NULL;
 102 }
 103
 104 const char *
 105 shishi_realm_for_server_dns (Shishi * handle, char *server)
 106 {
 107   const char *p = "JOSEFSSON.ORG";
 108
 109   fprintf (stderr,
 110            "warning: Assuming server `%s' is in realm `%s'\n"
 111            "warning: based on insecure DNS information.\n"
 112            "warning: Abort if this appear fruadulent.\n", server, p);
 113
 114   return p;
 115 }
 116
 117 const char *
 118 shishi_realm_for_server (Shishi * handle, char *server)
 119 {
 120   const char *p;
 121
 122   p = shishi_realm_for_server_file (handle, server);
 123   if (!p)
 124     p = shishi_realm_for_server_dns (handle, server);
 125
 126   return p;
 127 }