nis/nis_ismember.c

   1 /* Copyright (c) 1997-2021 Free Software Foundation, Inc.
   2    This file is part of the GNU C Library.
   3    Contributed by Thorsten Kukuk <kukuk@suse.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    <https://www.gnu.org/licenses/>.  */
  18
  19 #include <string.h>
  20 #include <rpcsvc/nis.h>
  21 #include <shlib-compat.h>
  22
  23 /* internal_nis_ismember ()
  24    return codes: -1 principal is in -group
  25                   0 principal isn't in any group
  26                   1 pirncipal is in group */
  27 static int
  28 internal_ismember (const_nis_name principal, const_nis_name group)
  29 {
  30   size_t grouplen = strlen (group);
  31   char buf[grouplen + 50];
  32   char leafbuf[grouplen + 2];
  33   char domainbuf[grouplen + 2];
  34   nis_result *res;
  35   char *cp, *cp2;
  36   u_int i;
  37
  38   cp = stpcpy (buf, nis_leaf_of_r (group, leafbuf, sizeof (leafbuf) - 1));
  39   cp = stpcpy (cp, ".groups_dir");
  40   cp2 = nis_domain_of_r (group, domainbuf, sizeof (domainbuf) - 1);
  41   if (cp2 != NULL && cp2[0] != '\0')
  42     {
  43       *cp++ = '.';
  44       strcpy (cp, cp2);
  45     }
  46
  47   res = nis_lookup (buf, EXPAND_NAME|FOLLOW_LINKS);
  48   if (res == NULL || NIS_RES_STATUS (res) != NIS_SUCCESS)
  49     {
  50       nis_freeresult (res);
  51       return 0;
  52     }
  53
  54   if ((NIS_RES_NUMOBJ (res) != 1)
  55       || (__type_of (NIS_RES_OBJECT (res)) != NIS_GROUP_OBJ))
  56     {
  57       nis_freeresult (res);
  58       return 0;
  59     }
  60
  61   /* We search twice in the list, at first, if we have the name
  62      with a "-", then if without. "-member" has priority */
  63   for (i = 0; i < NIS_RES_OBJECT(res)->GR_data.gr_members.gr_members_len; ++i)
  64     {
  65       cp = NIS_RES_OBJECT (res)->GR_data.gr_members.gr_members_val[i];
  66       if (cp[0] == '-')
  67         {
  68           if (strcmp (&cp[1], principal) == 0)
  69             {
  70               nis_freeresult (res);
  71               return -1;
  72             }
  73           if (cp[1] == '@')
  74             switch (internal_ismember (principal, &cp[2]))
  75               {
  76               case -1:
  77                 nis_freeresult (res);
  78                 return -1;
  79               case 1:
  80                 nis_freeresult (res);
  81                 return 1;
  82               default:
  83                 break;
  84               }
  85           else
  86             if (cp[1] == '*')
  87               {
  88                 char buf1[strlen (principal) + 2];
  89                 char buf2[strlen (cp) + 2];
  90
  91                 if (strcmp (nis_domain_of_r (principal, buf1, sizeof buf1),
  92                             nis_domain_of_r (cp, buf2, sizeof buf2)) == 0)
  93                   {
  94                     nis_freeresult (res);
  95                     return -1;
  96                   }
  97               }
  98         }
  99     }
 100
 101   for (i = 0; i < NIS_RES_OBJECT (res)->GR_data.gr_members.gr_members_len; ++i)
 102     {
 103       cp = NIS_RES_OBJECT (res)->GR_data.gr_members.gr_members_val[i];
 104       if (cp[0] != '-')
 105         {
 106           if (strcmp (cp, principal) == 0)
 107             {
 108               nis_freeresult (res);
 109               return 1;
 110             }
 111           if (cp[0] == '@')
 112             switch (internal_ismember (principal, &cp[1]))
 113               {
 114               case -1:
 115                 nis_freeresult (res);
 116                 return -1;
 117               case 1:
 118                 nis_freeresult (res);
 119                 return 1;
 120               default:
 121                 break;
 122               }
 123           else
 124             if (cp[0] == '*')
 125               {
 126                 char buf1[strlen (principal) + 2];
 127                 char buf2[strlen (cp) + 2];
 128
 129                 if (strcmp (nis_domain_of_r (principal, buf1, sizeof buf1),
 130                             nis_domain_of_r (cp, buf2, sizeof buf2)) == 0)
 131                   {
 132                     nis_freeresult (res);
 133                     return 1;
 134                   }
 135               }
 136         }
 137     }
 138   nis_freeresult (res);
 139   return 0;
 140 }
 141
 142 bool_t
 143 nis_ismember (const_nis_name principal, const_nis_name group)
 144 {
 145   if (group != NULL && group[0] != '\0' && principal != NULL)
 146     return internal_ismember (principal, group) == 1 ? TRUE : FALSE;
 147   else
 148     return FALSE;
 149 }
 150 libnsl_hidden_nolink_def (nis_ismember, GLIBC_2_1)