source3/smbd/connection.c

   1 /*
   2    Unix SMB/CIFS implementation.
   3    connection claim routines
   4    Copyright (C) Andrew Tridgell 1998
   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 #include "includes.h"
  21 #include "smbd/smbd.h"
  22 #include "smbd/globals.h"
  23 #include "dbwrap/dbwrap.h"
  24 #include "auth.h"
  25 #include "../lib/tsocket/tsocket.h"
  26
  27 /****************************************************************************
  28  Delete a connection record.
  29 ****************************************************************************/
  30
  31 bool yield_connection(connection_struct *conn, const char *name)
  32 {
  33         struct db_record *rec;
  34         NTSTATUS status;
  35
  36         DEBUG(3,("Yielding connection to %s\n",name));
  37
  38         rec = connections_fetch_entry(talloc_tos(), conn, name);
  39         if (rec == NULL) {
  40                 DEBUG(0, ("connections_fetch_entry failed\n"));
  41                 return False;
  42         }
  43
  44         status = dbwrap_record_delete(rec);
  45         if (!NT_STATUS_IS_OK(status)) {
  46                 DEBUG( NT_STATUS_EQUAL(status, NT_STATUS_NOT_FOUND) ? 3 : 0,
  47                        ("deleting connection record returned %s\n",
  48                         nt_errstr(status)));
  49         }
  50
  51         TALLOC_FREE(rec);
  52         return NT_STATUS_IS_OK(status);
  53 }
  54
  55 struct count_stat {
  56         int curr_connections;
  57         const char *name;
  58         bool Clear;
  59 };
  60
  61 /****************************************************************************
  62  Count the entries belonging to a service in the connection db.
  63 ****************************************************************************/
  64
  65 static int count_fn(struct db_record *rec,
  66                     const struct connections_key *ckey,
  67                     const struct connections_data *crec,
  68                     void *udp)
  69 {
  70         struct count_stat *cs = (struct count_stat *)udp;
  71
  72         if (crec->cnum == -1) {
  73                 return 0;
  74         }
  75
  76         /* If the pid was not found delete the entry from connections.tdb */
  77
  78         if (cs->Clear && !process_exists(crec->pid) && (errno == ESRCH)) {
  79                 NTSTATUS status;
  80                 DEBUG(2,("pid %s doesn't exist - deleting connections %d [%s]\n",
  81                          procid_str_static(&crec->pid), crec->cnum,
  82                          crec->servicename));
  83
  84                 status = dbwrap_record_delete(rec);
  85                 if (!NT_STATUS_IS_OK(status)) {
  86                         DEBUG(0,("count_fn: tdb_delete failed with error %s\n",
  87                                  nt_errstr(status)));
  88                 }
  89                 return 0;
  90         }
  91
  92         if (strequal(crec->servicename, cs->name))
  93                 cs->curr_connections++;
  94
  95         return 0;
  96 }
  97
  98 /****************************************************************************
  99  Claim an entry in the connections database.
 100 ****************************************************************************/
 101
 102 int count_current_connections( const char *sharename, bool clear  )
 103 {
 104         struct count_stat cs;
 105         int ret;
 106
 107         cs.curr_connections = 0;
 108         cs.name = sharename;
 109         cs.Clear = clear;
 110
 111         /*
 112          * This has a race condition, but locking the chain before hand is worse
 113          * as it leads to deadlock.
 114          */
 115
 116         /*
 117          * become_root() because we might have to open connections.tdb
 118          * via ctdb, which is not possible without root.
 119          */
 120         become_root();
 121         ret = connections_forall(count_fn, &cs);
 122         unbecome_root();
 123
 124         if (ret < 0) {
 125                 DEBUG(0,("count_current_connections: traverse of "
 126                          "connections.tdb failed\n"));
 127                 return 0;
 128         }
 129
 130         return cs.curr_connections;
 131 }
 132
 133 bool connections_snum_used(struct smbd_server_connection *unused, int snum)
 134 {
 135         int active;
 136
 137         active = count_current_connections(lp_servicename(snum), true);
 138         if (active > 0) {
 139                 return true;
 140         }
 141
 142         return false;
 143 }
 144
 145 /****************************************************************************
 146  Claim an entry in the connections database.
 147 ****************************************************************************/
 148
 149 bool claim_connection(connection_struct *conn, const char *name)
 150 {
 151         struct db_record *rec;
 152         struct connections_data crec;
 153         char *raddr;
 154         TDB_DATA dbuf;
 155         NTSTATUS status;
 156
 157         DEBUG(5,("claiming [%s]\n", name));
 158
 159         if (!(rec = connections_fetch_entry(talloc_tos(), conn, name))) {
 160                 DEBUG(0, ("connections_fetch_entry failed\n"));
 161                 return False;
 162         }
 163
 164         /* Make clear that we require the optional unix_token in the source3 code */
 165         SMB_ASSERT(conn->session_info->unix_token);
 166
 167         /* fill in the crec */
 168         ZERO_STRUCT(crec);
 169         crec.magic = 0x280267;
 170         crec.pid = sconn_server_id(conn->sconn);
 171         crec.cnum = conn->cnum;
 172         crec.uid = conn->session_info->unix_token->uid;
 173         crec.gid = conn->session_info->unix_token->gid;
 174         strlcpy(crec.servicename, lp_servicename(SNUM(conn)),
 175                 sizeof(crec.servicename));
 176         crec.start = time(NULL);
 177
 178         raddr = tsocket_address_inet_addr_string(conn->sconn->remote_address,
 179                                                  talloc_tos());
 180         if (raddr == NULL) {
 181                 return false;
 182         }
 183
 184         strlcpy(crec.machine,get_remote_machine_name(),sizeof(crec.machine));
 185         strlcpy(crec.addr, raddr, sizeof(crec.addr));
 186
 187         dbuf.dptr = (uint8 *)&crec;
 188         dbuf.dsize = sizeof(crec);
 189
 190         status = dbwrap_record_store(rec, dbuf, TDB_REPLACE);
 191
 192         TALLOC_FREE(rec);
 193
 194         if (!NT_STATUS_IS_OK(status)) {
 195                 DEBUG(0,("claim_connection: tdb_store failed with error %s.\n",
 196                          nt_errstr(status)));
 197                 return False;
 198         }
 199
 200         return True;
 201 }