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.h"
  24
  25 /****************************************************************************
  26  Delete a connection record.
  27 ****************************************************************************/
  28
  29 bool yield_connection(connection_struct *conn, const char *name)
  30 {
  31         struct db_record *rec;
  32         NTSTATUS status;
  33
  34         DEBUG(3,("Yielding connection to %s\n",name));
  35
  36         rec = connections_fetch_entry(talloc_tos(), conn, name);
  37         if (rec == NULL) {
  38                 DEBUG(0, ("connections_fetch_entry failed\n"));
  39                 return False;
  40         }
  41
  42         status = rec->delete_rec(rec);
  43         if (!NT_STATUS_IS_OK(status)) {
  44                 DEBUG( NT_STATUS_EQUAL(status, NT_STATUS_NOT_FOUND) ? 3 : 0,
  45                        ("deleting connection record returned %s\n",
  46                         nt_errstr(status)));
  47         }
  48
  49         TALLOC_FREE(rec);
  50         return NT_STATUS_IS_OK(status);
  51 }
  52
  53 struct count_stat {
  54         int curr_connections;
  55         const char *name;
  56         bool Clear;
  57 };
  58
  59 /****************************************************************************
  60  Count the entries belonging to a service in the connection db.
  61 ****************************************************************************/
  62
  63 static int count_fn(struct db_record *rec,
  64                     const struct connections_key *ckey,
  65                     const struct connections_data *crec,
  66                     void *udp)
  67 {
  68         struct count_stat *cs = (struct count_stat *)udp;
  69
  70         if (crec->cnum == -1) {
  71                 return 0;
  72         }
  73
  74         /* If the pid was not found delete the entry from connections.tdb */
  75
  76         if (cs->Clear && !process_exists(crec->pid) && (errno == ESRCH)) {
  77                 NTSTATUS status;
  78                 DEBUG(2,("pid %s doesn't exist - deleting connections %d [%s]\n",
  79                          procid_str_static(&crec->pid), crec->cnum,
  80                          crec->servicename));
  81
  82                 status = rec->delete_rec(rec);
  83                 if (!NT_STATUS_IS_OK(status)) {
  84                         DEBUG(0,("count_fn: tdb_delete failed with error %s\n",
  85                                  nt_errstr(status)));
  86                 }
  87                 return 0;
  88         }
  89
  90         if (strequal(crec->servicename, cs->name))
  91                 cs->curr_connections++;
  92
  93         return 0;
  94 }
  95
  96 /****************************************************************************
  97  Claim an entry in the connections database.
  98 ****************************************************************************/
  99
 100 int count_current_connections( const char *sharename, bool clear  )
 101 {
 102         struct count_stat cs;
 103
 104         cs.curr_connections = 0;
 105         cs.name = sharename;
 106         cs.Clear = clear;
 107
 108         /*
 109          * This has a race condition, but locking the chain before hand is worse
 110          * as it leads to deadlock.
 111          */
 112
 113         if (connections_forall(count_fn, &cs) == -1) {
 114                 DEBUG(0,("count_current_connections: traverse of "
 115                          "connections.tdb failed\n"));
 116                 return False;
 117         }
 118
 119         return cs.curr_connections;
 120 }
 121
 122 /****************************************************************************
 123  Claim an entry in the connections database.
 124 ****************************************************************************/
 125
 126 bool claim_connection(connection_struct *conn, const char *name)
 127 {
 128         struct db_record *rec;
 129         struct connections_data crec;
 130         TDB_DATA dbuf;
 131         NTSTATUS status;
 132
 133         DEBUG(5,("claiming [%s]\n", name));
 134
 135         if (!(rec = connections_fetch_entry(talloc_tos(), conn, name))) {
 136                 DEBUG(0, ("connections_fetch_entry failed\n"));
 137                 return False;
 138         }
 139
 140         /* fill in the crec */
 141         ZERO_STRUCT(crec);
 142         crec.magic = 0x280267;
 143         crec.pid = sconn_server_id(conn->sconn);
 144         crec.cnum = conn->cnum;
 145         crec.uid = conn->session_info->utok.uid;
 146         crec.gid = conn->session_info->utok.gid;
 147         strlcpy(crec.servicename, lp_servicename(SNUM(conn)),
 148                 sizeof(crec.servicename));
 149         crec.start = time(NULL);
 150
 151         strlcpy(crec.machine,get_remote_machine_name(),sizeof(crec.machine));
 152         strlcpy(crec.addr, conn->sconn->client_id.addr, sizeof(crec.addr));
 153
 154         dbuf.dptr = (uint8 *)&crec;
 155         dbuf.dsize = sizeof(crec);
 156
 157         status = rec->store(rec, dbuf, TDB_REPLACE);
 158
 159         TALLOC_FREE(rec);
 160
 161         if (!NT_STATUS_IS_OK(status)) {
 162                 DEBUG(0,("claim_connection: tdb_store failed with error %s.\n",
 163                          nt_errstr(status)));
 164                 return False;
 165         }
 166
 167         return True;
 168 }