source/smbd/groupname.c

   1 /*
   2    Unix SMB/Netbios implementation.
   3    Version 1.9.
   4    Groupname handling
   5    Copyright (C) Jeremy Allison 1998.
   6
   7    This program is free software; you can redistribute it and/or modify
   8    it under the terms of the GNU General Public License as published by
   9    the Free Software Foundation; either version 2 of the License, or
  10    (at your option) any later version.
  11
  12    This program is distributed in the hope that it will be useful,
  13    but WITHOUT ANY WARRANTY; without even the implied warranty of
  14    MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  15    GNU General Public License for more details.
  16
  17    You should have received a copy of the GNU General Public License
  18    along with this program; if not, write to the Free Software
  19    Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA.
  20 */
  21
  22 #ifdef USING_GROUPNAME_MAP
  23
  24 #include "includes.h"
  25 extern int DEBUGLEVEL;
  26 extern DOM_SID global_sam_sid;
  27
  28
  29 /**************************************************************************
  30  Groupname map functionality. The code loads a groupname map file and
  31  (currently) loads it into a linked list. This is slow and memory
  32  hungry, but can be changed into a more efficient storage format
  33  if the demands on it become excessive.
  34 ***************************************************************************/
  35
  36 typedef struct groupname_map {
  37    ubi_slNode next;
  38
  39    char *windows_name;
  40    DOM_SID windows_sid;
  41    char *unix_name;
  42    gid_t unix_gid;
  43 } groupname_map_entry;
  44
  45 static ubi_slList groupname_map_list;
  46
  47 /**************************************************************************
  48  Delete all the entries in the groupname map list.
  49 ***************************************************************************/
  50
  51 static void delete_groupname_map_list(void)
  52 {
  53   groupname_map_entry *gmep;
  54
  55   while((gmep = (groupname_map_entry *)ubi_slRemHead( &groupname_map_list )) != NULL) {
  56     if(gmep->windows_name)
  57       free(gmep->windows_name);
  58     if(gmep->unix_name)
  59       free(gmep->unix_name);
  60     free((char *)gmep);
  61   }
  62 }
  63
  64 /**************************************************************************
  65  Load a groupname map file. Sets last accessed timestamp.
  66 ***************************************************************************/
  67
  68 void load_groupname_map(void)
  69 {
  70   static time_t groupmap_file_last_modified = (time_t)0;
  71   static BOOL initialized = False;
  72   char *groupname_map_file = lp_groupname_map();
  73   SMB_STRUCT_STAT st;
  74   FILE *fp;
  75   char *s;
  76   pstring buf;
  77   groupname_map_entry *new_ep;
  78
  79   if(!initialized) {
  80     ubi_slInitList( &groupname_map_list );
  81     initialized = True;
  82   }
  83
  84   if (!*groupname_map_file)
  85     return;
  86
  87   if(sys_stat(groupname_map_file, &st) != 0) {
  88     DEBUG(0, ("load_groupname_map: Unable to stat file %s. Error was %s\n",
  89                groupname_map_file, strerror(errno) ));
  90     return;
  91   }
  92
  93   /*
  94    * Check if file has changed.
  95    */
  96   if( st.st_mtime <= groupmap_file_last_modified)
  97     return;
  98
  99   groupmap_file_last_modified = st.st_mtime;
 100
 101   /*
 102    * Load the file.
 103    */
 104
 105   fp = sys_fopen(groupname_map_file,"r");
 106   if (!fp) {
 107     DEBUG(0,("load_groupname_map: can't open groupname map %s. Error was %s\n",
 108           groupname_map_file, strerror(errno)));
 109     return;
 110   }
 111
 112   /*
 113    * Throw away any previous list.
 114    */
 115   delete_groupname_map_list();
 116
 117   DEBUG(4,("load_groupname_map: Scanning groupname map %s\n",groupname_map_file));
 118
 119   while((s=fgets_slash(buf,sizeof(buf),fp))!=NULL) {
 120     pstring unixname;
 121     pstring windows_name;
 122     struct group *gptr;
 123     DOM_SID tmp_sid;
 124
 125     DEBUG(10,("load_groupname_map: Read line |%s|\n", s));
 126
 127     if (!*s || strchr("#;",*s))
 128       continue;
 129
 130     if(!next_token(&s,unixname, "\t\n\r=", sizeof(unixname)))
 131       continue;
 132
 133     if(!next_token(&s,windows_name, "\t\n\r=", sizeof(windows_name)))
 134       continue;
 135
 136     trim_string(unixname, " ", " ");
 137     trim_string(windows_name, " ", " ");
 138
 139     if (!*windows_name)
 140       continue;
 141
 142     if(!*unixname)
 143       continue;
 144
 145     DEBUG(5,("load_groupname_map: unixname = %s, windowsname = %s.\n",
 146              unixname, windows_name));
 147
 148     /*
 149      * Attempt to get the unix gid_t for this name.
 150      */
 151
 152     if((gptr = (struct group *)getgrnam(unixname)) == NULL) {
 153       DEBUG(0,("load_groupname_map: getgrnam for group %s failed.\
 154 Error was %s.\n", unixname, strerror(errno) ));
 155       continue;
 156     }
 157
 158     /*
 159      * Now map to an NT SID.
 160      */
 161
 162     if(!lookup_wellknown_sid_from_name(windows_name, &tmp_sid)) {
 163       /*
 164        * It's not a well known name, convert the UNIX gid_t
 165        * to a rid within this domain SID.
 166        */
 167       tmp_sid = global_sam_sid;
 168       tmp_sid.sub_auths[tmp_sid.num_auths++] =
 169                     pdb_gid_to_group_rid((gid_t)gptr->gr_gid);
 170     }
 171
 172     /*
 173      * Create the list entry and add it onto the list.
 174      */
 175
 176     if((new_ep = (groupname_map_entry *)malloc( sizeof(groupname_map_entry) ))== NULL) {
 177       DEBUG(0,("load_groupname_map: malloc fail for groupname_map_entry.\n"));
 178       fclose(fp);
 179       return;
 180     }
 181
 182     new_ep->unix_gid = gptr->gr_gid;
 183     new_ep->windows_sid = tmp_sid;
 184     new_ep->windows_name = strdup( windows_name );
 185     new_ep->unix_name = strdup( unixname );
 186
 187     if(new_ep->windows_name == NULL || new_ep->unix_name == NULL) {
 188       DEBUG(0,("load_groupname_map: malloc fail for names in groupname_map_entry.\n"));
 189       fclose(fp);
 190       if(new_ep->windows_name != NULL)
 191         free(new_ep->windows_name);
 192       if(new_ep->unix_name != NULL)
 193         free(new_ep->unix_name);
 194       free((char *)new_ep);
 195       return;
 196     }
 197     memset((char *)&new_ep->next, '\0', sizeof(new_ep->next) );
 198
 199     ubi_slAddHead( &groupname_map_list, (ubi_slNode *)new_ep);
 200   }
 201
 202   DEBUG(10,("load_groupname_map: Added %ld entries to groupname map.\n",
 203             ubi_slCount(&groupname_map_list)));
 204
 205   fclose(fp);
 206 }
 207
 208 /***********************************************************
 209  Lookup a SID entry by gid_t.
 210 ************************************************************/
 211
 212 void map_gid_to_sid( gid_t gid, DOM_SID *psid)
 213 {
 214   groupname_map_entry *gmep;
 215
 216   /*
 217    * Initialize and load if not already loaded.
 218    */
 219   load_groupname_map();
 220
 221   for( gmep = (groupname_map_entry *)ubi_slFirst( &groupname_map_list);
 222        gmep; gmep = (groupname_map_entry *)ubi_slNext( gmep )) {
 223
 224     if( gmep->unix_gid == gid) {
 225       *psid = gmep->windows_sid;
 226       DEBUG(7,("map_gid_to_sid: Mapping unix group %s to windows group %s.\n",
 227                gmep->unix_name, gmep->windows_name ));
 228       return;
 229     }
 230   }
 231
 232   /*
 233    * If there's no map, convert the UNIX gid_t
 234    * to a rid within this domain SID.
 235    */
 236   *psid = global_sam_sid;
 237   psid->sub_auths[psid->num_auths++] = pdb_gid_to_group_rid(gid);
 238
 239   return;
 240 }
 241 #else /* USING_GROUPNAME_MAP */
 242  void load_groupname_map(void) {;}
 243 #endif /* USING_GROUPNAME_MAP */