nis/nis_ismember.c

   1 /* Copyright (c) 1997-2024 Free Software Foundation, Inc.
   2    This file is part of the GNU C Library.
   3
   4    The GNU C Library is free software; you can redistribute it and/or
   5    modify it under the terms of the GNU Lesser General Public
   6    License as published by the Free Software Foundation; either
   7    version 2.1 of the License, or (at your option) any later version.
   8
   9    The GNU C Library is distributed in the hope that it will be useful,
  10    but WITHOUT ANY WARRANTY; without even the implied warranty of
  11    MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
  12    Lesser General Public License for more details.
  13
  14    You should have received a copy of the GNU Lesser General Public
  15    License along with the GNU C Library; if not, see
  16    <https://www.gnu.org/licenses/>.  */
  17
  18 #include <string.h>
  19 #include <rpcsvc/nis.h>
  20 #include <shlib-compat.h>
  21
  22 /* internal_nis_ismember ()
  23    return codes: -1 principal is in -group
  24                   0 principal isn't in any group
  25                   1 pirncipal is in group */
  26 static int
  27 internal_ismember (const_nis_name principal, const_nis_name group)
  28 {
  29   size_t grouplen = strlen (group);
  30   char buf[grouplen + 50];
  31   char leafbuf[grouplen + 2];
  32   char domainbuf[grouplen + 2];
  33   nis_result *res;
  34   char *cp, *cp2;
  35   u_int i;
  36
  37   cp = stpcpy (buf, nis_leaf_of_r (group, leafbuf, sizeof (leafbuf) - 1));
  38   cp = stpcpy (cp, ".groups_dir");
  39   cp2 = nis_domain_of_r (group, domainbuf, sizeof (domainbuf) - 1);
  40   if (cp2 != NULL && cp2[0] != '\0')
  41     {
  42       *cp++ = '.';
  43       strcpy (cp, cp2);
  44     }
  45
  46   res = nis_lookup (buf, EXPAND_NAME|FOLLOW_LINKS);
  47   if (res == NULL || NIS_RES_STATUS (res) != NIS_SUCCESS)
  48     {
  49       nis_freeresult (res);
  50       return 0;
  51     }
  52
  53   if ((NIS_RES_NUMOBJ (res) != 1)
  54       || (__type_of (NIS_RES_OBJECT (res)) != NIS_GROUP_OBJ))
  55     {
  56       nis_freeresult (res);
  57       return 0;
  58     }
  59
  60   /* We search twice in the list, at first, if we have the name
  61      with a "-", then if without. "-member" has priority */
  62   for (i = 0; i < NIS_RES_OBJECT(res)->GR_data.gr_members.gr_members_len; ++i)
  63     {
  64       cp = NIS_RES_OBJECT (res)->GR_data.gr_members.gr_members_val[i];
  65       if (cp[0] == '-')
  66         {
  67           if (strcmp (&cp[1], principal) == 0)
  68             {
  69               nis_freeresult (res);
  70               return -1;
  71             }
  72           if (cp[1] == '@')
  73             switch (internal_ismember (principal, &cp[2]))
  74               {
  75               case -1:
  76                 nis_freeresult (res);
  77                 return -1;
  78               case 1:
  79                 nis_freeresult (res);
  80                 return 1;
  81               default:
  82                 break;
  83               }
  84           else
  85             if (cp[1] == '*')
  86               {
  87                 char buf1[strlen (principal) + 2];
  88                 char buf2[strlen (cp) + 2];
  89
  90                 if (strcmp (nis_domain_of_r (principal, buf1, sizeof buf1),
  91                             nis_domain_of_r (cp, buf2, sizeof buf2)) == 0)
  92                   {
  93                     nis_freeresult (res);
  94                     return -1;
  95                   }
  96               }
  97         }
  98     }
  99
 100   for (i = 0; i < NIS_RES_OBJECT (res)->GR_data.gr_members.gr_members_len; ++i)
 101     {
 102       cp = NIS_RES_OBJECT (res)->GR_data.gr_members.gr_members_val[i];
 103       if (cp[0] != '-')
 104         {
 105           if (strcmp (cp, principal) == 0)
 106             {
 107               nis_freeresult (res);
 108               return 1;
 109             }
 110           if (cp[0] == '@')
 111             switch (internal_ismember (principal, &cp[1]))
 112               {
 113               case -1:
 114                 nis_freeresult (res);
 115                 return -1;
 116               case 1:
 117                 nis_freeresult (res);
 118                 return 1;
 119               default:
 120                 break;
 121               }
 122           else
 123             if (cp[0] == '*')
 124               {
 125                 char buf1[strlen (principal) + 2];
 126                 char buf2[strlen (cp) + 2];
 127
 128                 if (strcmp (nis_domain_of_r (principal, buf1, sizeof buf1),
 129                             nis_domain_of_r (cp, buf2, sizeof buf2)) == 0)
 130                   {
 131                     nis_freeresult (res);
 132                     return 1;
 133                   }
 134               }
 135         }
 136     }
 137   nis_freeresult (res);
 138   return 0;
 139 }
 140
 141 bool_t
 142 nis_ismember (const_nis_name principal, const_nis_name group)
 143 {
 144   if (group != NULL && group[0] != '\0' && principal != NULL)
 145     return internal_ismember (principal, group) == 1 ? TRUE : FALSE;
 146   else
 147     return FALSE;
 148 }
 149 libnsl_hidden_nolink_def (nis_ismember, GLIBC_2_1)