nis/nis_local_names.c

   1 /* Copyright (c) 1997-2015 Free Software Foundation, Inc.
   2    This file is part of the GNU C Library.
   3    Contributed by Thorsten Kukuk <kukuk@vt.uni-paderborn.de>, 1997.
   4
   5    The GNU C Library is free software; you can redistribute it and/or
   6    modify it under the terms of the GNU Lesser General Public
   7    License as published by the Free Software Foundation; either
   8    version 2.1 of the License, or (at your option) any later version.
   9
  10    The GNU C Library is distributed in the hope that it will be useful,
  11    but WITHOUT ANY WARRANTY; without even the implied warranty of
  12    MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
  13    Lesser General Public License for more details.
  14
  15    You should have received a copy of the GNU Lesser General Public
  16    License along with the GNU C Library; if not, see
  17    <http://www.gnu.org/licenses/>.  */
  18
  19 #include <errno.h>
  20 #include <string.h>
  21 #include <unistd.h>
  22 #include <libintl.h>
  23 #include <rpcsvc/nis.h>
  24
  25 nis_name
  26 nis_local_group (void)
  27 {
  28   static char __nisgroup[NIS_MAXNAMELEN + 1];
  29
  30   char *cptr;
  31   if (__nisgroup[0] == '\0'
  32       && (cptr = getenv ("NIS_GROUP")) != NULL
  33       && strlen (cptr) < NIS_MAXNAMELEN)
  34     {
  35       char *cp = stpcpy (__nisgroup, cptr);
  36
  37       if (cp[-1] != '.')
  38         {
  39           cptr = nis_local_directory ();
  40           if ((cp - __nisgroup) + strlen (cptr) + 1 < NIS_MAXNAMELEN)
  41             {
  42               *cp++ = '.';
  43               strcpy (cp, cptr);
  44             }
  45           else
  46             __nisgroup[0] = '\0';
  47         }
  48     }
  49
  50   return __nisgroup;
  51 }
  52 libnsl_hidden_def (nis_local_group)
  53
  54 nis_name
  55 nis_local_directory (void)
  56 {
  57   static char __nisdomainname[NIS_MAXNAMELEN + 1];
  58
  59   if (__nisdomainname[0] == '\0')
  60     {
  61       if (getdomainname (__nisdomainname, NIS_MAXNAMELEN) < 0)
  62         __nisdomainname[0] = '\0';
  63       else
  64         {
  65           char *cp = rawmemchr (__nisdomainname, '\0');
  66
  67           /* Missing trailing dot? */
  68           if (cp[-1] != '.')
  69             {
  70               *cp++ = '.';
  71               *cp = '\0';
  72             }
  73         }
  74     }
  75
  76   return __nisdomainname;
  77 }
  78 libnsl_hidden_def (nis_local_directory)
  79
  80 nis_name
  81 nis_local_principal (void)
  82 {
  83   static char __principal[NIS_MAXNAMELEN + 1];
  84
  85   if (__principal[0] == '\0')
  86     {
  87       char buf[NIS_MAXNAMELEN + 1];
  88       nis_result *res;
  89       uid_t uid = geteuid ();
  90
  91       if (uid != 0)
  92         {
  93           int len = snprintf (buf, NIS_MAXNAMELEN - 1,
  94                               "[auth_name=%d,auth_type=LOCAL],cred.org_dir.%s",
  95                               uid, nis_local_directory ());
  96
  97           if (len >= NIS_MAXNAMELEN - 1)
  98             nobody:
  99             /* XXX The buffer is too small.  Can this happen???  */
 100             return strcpy (__principal, "nobody");
 101
 102           if (buf[len - 1] != '.')
 103             {
 104               buf[len++] = '.';
 105               buf[len] = '\0';
 106             }
 107
 108           res = nis_list (buf, USE_DGRAM + NO_AUTHINFO + FOLLOW_LINKS +
 109                           FOLLOW_PATH, NULL, NULL);
 110
 111           if (res == NULL)
 112             goto nobody;
 113
 114           if (NIS_RES_STATUS (res) == NIS_SUCCESS)
 115             {
 116               if (res->objects.objects_len > 1)
 117                 {
 118                   /* More than one principal with same uid?  something
 119                      wrong with cred table.  Should be unique.  Warn user
 120                      and continue.  */
 121                   printf (_("\
 122 LOCAL entry for UID %d in directory %s not unique\n"),
 123                           uid, nis_local_directory ());
 124                 }
 125               strcpy (__principal, ENTRY_VAL (res->objects.objects_val, 0));
 126               nis_freeresult (res);
 127               return __principal;
 128             }
 129           else
 130             {
 131               nis_freeresult (res);
 132               goto nobody;
 133             }
 134         }
 135       else
 136         return strcpy (__principal, nis_local_host ());
 137
 138       /* Should be never reached */
 139       goto nobody;
 140     }
 141   return __principal;
 142 }
 143 libnsl_hidden_def (nis_local_principal)
 144
 145 nis_name
 146 nis_local_host (void)
 147 {
 148   static char __nishostname[NIS_MAXNAMELEN + 1];
 149
 150   if (__nishostname[0] == '\0')
 151     {
 152       if (gethostname (__nishostname, NIS_MAXNAMELEN) < 0)
 153         __nishostname[0] = '\0';
 154       else
 155         {
 156           char *cp = rawmemchr (__nishostname, '\0');
 157           int len = cp - __nishostname;
 158
 159           /* Hostname already fully qualified? */
 160           if (cp[-1] == '.')
 161             return __nishostname;
 162
 163           if (len + strlen (nis_local_directory ()) + 1 > NIS_MAXNAMELEN)
 164             {
 165               __nishostname[0] = '\0';
 166               return __nishostname;
 167             }
 168
 169           *cp++ = '.';
 170           strncpy (cp, nis_local_directory (), NIS_MAXNAMELEN - len -1);
 171           __nishostname[NIS_MAXNAMELEN] = '\0';
 172         }
 173     }
 174
 175   return __nishostname;
 176 }
 177 libnsl_hidden_def (nis_local_host)