source3/smbd/msg_idmap.c

   1 /*
   2  * Samba Unix/Linux SMB client library
   3  *
   4  * Copyright (C) Gregor Beck 2011
   5  *
   6  * This program 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 3 of the License, or
   9  * (at your option) any later version.
  10  *
  11  * This program 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 this program.  If not, see <http://www.gnu.org/licenses/>.
  18  */
  19
  20 /**
  21  * @brief  Notify smbd about idmap changes
  22  * @file   msg_idmap.c
  23  * @author Gregor Beck <gb@sernet.de>
  24  * @date   Feb 2011
  25  *
  26  */
  27
  28 #include "includes.h"
  29 #include "smbd/smbd.h"
  30 #include "globals.h"
  31 #include "../libcli/security/dom_sid.h"
  32 #include "idmap_cache.h"
  33 #include "passdb/lookup_sid.h"
  34 #include "auth.h"
  35 #include "messages.h"
  36
  37 struct id {
  38         union {
  39                 uid_t uid;
  40                 gid_t gid;
  41                 struct dom_sid sid;
  42         } id;
  43         enum {UID, GID, SID} type;
  44 };
  45
  46 static bool parse_id(const char* str, struct id* id)
  47 {
  48         struct dom_sid sid;
  49         unsigned long ul;
  50         char c, trash;
  51
  52         if (sscanf(str, "%cID %lu%c", &c, &ul, &trash) == 2) {
  53                 switch(c) {
  54                 case 'G':
  55                         id->id.gid = ul;
  56                         id->type = GID;
  57                         return true;
  58                 case 'U':
  59                         id->id.uid = ul;
  60                         id->type = UID;
  61                         return true;
  62                 default:
  63                         break;
  64                 }
  65         } else if (string_to_sid(&sid, str)) {
  66                 id->id.sid = sid;
  67                 id->type = SID;
  68                 return true;
  69         }
  70         return false;
  71 }
  72
  73 static bool uid_in_use(const struct user_struct* user, uid_t uid)
  74 {
  75         while (user) {
  76                 if (user->session_info && (user->session_info->utok.uid == uid)) {
  77                         return true;
  78                 }
  79                 user = user->next;
  80         }
  81         return false;
  82 }
  83
  84 static bool gid_in_use(const struct user_struct* user, gid_t gid)
  85 {
  86         while (user) {
  87                 if (user->session_info != NULL) {
  88                         int i;
  89                         struct security_unix_token utok = user->session_info->utok;
  90                         if (utok.gid == gid) {
  91                                 return true;
  92                         }
  93                         for(i=0; i<utok.ngroups; i++) {
  94                                 if (utok.groups[i] == gid) {
  95                                         return true;
  96                                 }
  97                         }
  98                 }
  99                 user = user->next;
 100         }
 101         return false;
 102 }
 103
 104 static bool sid_in_use(const struct user_struct* user, const struct dom_sid* psid)
 105 {
 106         uid_t uid;
 107         gid_t gid;
 108         if (sid_to_gid(psid, &gid)) {
 109                 return gid_in_use(user, gid);
 110         } else if (sid_to_uid(psid, &uid)) {
 111                 return uid_in_use(user, uid);
 112         }
 113         return false;
 114 }
 115
 116
 117 static bool id_in_use(const struct user_struct* user, const struct id* id)
 118 {
 119         switch(id->type) {
 120         case UID:
 121                 return uid_in_use(user, id->id.uid);
 122         case GID:
 123                 return gid_in_use(user, id->id.gid);
 124         case SID:
 125                 return sid_in_use(user, &id->id.sid);
 126         default:
 127                 break;
 128         }
 129         return false;
 130 }
 131
 132 static void delete_from_cache(const struct id* id)
 133 {
 134         switch(id->type) {
 135         case UID:
 136                 delete_uid_cache(id->id.uid);
 137                 idmap_cache_del_uid(id->id.uid);
 138                 break;
 139         case GID:
 140                 delete_gid_cache(id->id.gid);
 141                 idmap_cache_del_gid(id->id.gid);
 142                 break;
 143         case SID:
 144                 delete_sid_cache(&id->id.sid);
 145                 idmap_cache_del_sid(&id->id.sid);
 146                 break;
 147         default:
 148                 break;
 149         }
 150 }
 151
 152
 153 static void message_idmap_flush(struct messaging_context *msg_ctx,
 154                                 void* private_data,
 155                                 uint32_t msg_type,
 156                                 struct server_id server_id,
 157                                 DATA_BLOB* data)
 158 {
 159         const char* msg = data ? (const char*)data->data : NULL;
 160
 161         if ((msg == NULL) || (msg[0] == '\0')) {
 162                 flush_gid_cache();
 163                 flush_uid_cache();
 164         } else if (strncmp(msg, "GID", 3)) {
 165                 flush_gid_cache();
 166         } else if (strncmp(msg, "UID", 3)) {
 167                 flush_uid_cache();
 168         } else {
 169                 DEBUG(0, ("Invalid argument: %s\n", msg));
 170         }
 171 }
 172
 173
 174 static void message_idmap_delete(struct messaging_context *msg_ctx,
 175                                  void* private_data,
 176                                  uint32_t msg_type,
 177                                  struct server_id server_id,
 178                                  DATA_BLOB* data)
 179 {
 180         const char* msg = (data && data->data) ? (const char*)data->data : "<NULL>";
 181         bool do_kill = (msg_type == MSG_IDMAP_KILL);
 182         struct user_struct* validated_users = smbd_server_conn->smb1.sessions.validated_users;
 183         struct id id;
 184
 185         if (!parse_id(msg, &id)) {
 186                 DEBUG(0, ("Invalid ?ID: %s\n", msg));
 187                 return;
 188         }
 189
 190         if( do_kill && id_in_use(validated_users, &id) ) {
 191                 exit_server_cleanly(msg);
 192         } else {
 193                 delete_from_cache(&id);
 194         }
 195 }
 196
 197 void msg_idmap_register_msgs(struct messaging_context *ctx)
 198 {
 199         messaging_register(ctx, NULL, MSG_IDMAP_FLUSH,  message_idmap_flush);
 200         messaging_register(ctx, NULL, MSG_IDMAP_DELETE, message_idmap_delete);
 201         messaging_register(ctx, NULL, MSG_IDMAP_KILL,   message_idmap_delete);
 202 }