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/globals.h"
  22
  23 /****************************************************************************
  24  Delete a connection record.
  25 ****************************************************************************/
  26
  27 bool yield_connection(connection_struct *conn, const char *name)
  28 {
  29         struct db_record *rec;
  30         NTSTATUS status;
  31
  32         DEBUG(3,("Yielding connection to %s\n",name));
  33
  34         rec = connections_fetch_entry(talloc_tos(), conn, name);
  35         if (rec == NULL) {
  36                 DEBUG(0, ("connections_fetch_entry failed\n"));
  37                 return False;
  38         }
  39
  40         status = rec->delete_rec(rec);
  41         if (!NT_STATUS_IS_OK(status)) {
  42                 DEBUG( NT_STATUS_EQUAL(status, NT_STATUS_NOT_FOUND) ? 3 : 0,
  43                        ("deleting connection record returned %s\n",
  44                         nt_errstr(status)));
  45         }
  46
  47         TALLOC_FREE(rec);
  48         return NT_STATUS_IS_OK(status);
  49 }
  50
  51 struct count_stat {
  52         int curr_connections;
  53         const char *name;
  54         bool Clear;
  55 };
  56
  57 /****************************************************************************
  58  Count the entries belonging to a service in the connection db.
  59 ****************************************************************************/
  60
  61 static int count_fn(struct db_record *rec,
  62                     const struct connections_key *ckey,
  63                     const struct connections_data *crec,
  64                     void *udp)
  65 {
  66         struct count_stat *cs = (struct count_stat *)udp;
  67
  68         if (crec->cnum == -1) {
  69                 return 0;
  70         }
  71
  72         /* If the pid was not found delete the entry from connections.tdb */
  73
  74         if (cs->Clear && !process_exists(crec->pid) && (errno == ESRCH)) {
  75                 NTSTATUS status;
  76                 DEBUG(2,("pid %s doesn't exist - deleting connections %d [%s]\n",
  77                          procid_str_static(&crec->pid), crec->cnum,
  78                          crec->servicename));
  79
  80                 status = rec->delete_rec(rec);
  81                 if (!NT_STATUS_IS_OK(status)) {
  82                         DEBUG(0,("count_fn: tdb_delete failed with error %s\n",
  83                                  nt_errstr(status)));
  84                 }
  85                 return 0;
  86         }
  87
  88         if (strequal(crec->servicename, cs->name))
  89                 cs->curr_connections++;
  90
  91         return 0;
  92 }
  93
  94 /****************************************************************************
  95  Claim an entry in the connections database.
  96 ****************************************************************************/
  97
  98 int count_current_connections( const char *sharename, bool clear  )
  99 {
 100         struct count_stat cs;
 101
 102         cs.curr_connections = 0;
 103         cs.name = sharename;
 104         cs.Clear = clear;
 105
 106         /*
 107          * This has a race condition, but locking the chain before hand is worse
 108          * as it leads to deadlock.
 109          */
 110
 111         if (connections_forall(count_fn, &cs) == -1) {
 112                 DEBUG(0,("count_current_connections: traverse of "
 113                          "connections.tdb failed\n"));
 114                 return False;
 115         }
 116
 117         return cs.curr_connections;
 118 }
 119
 120 /****************************************************************************
 121  Claim an entry in the connections database.
 122 ****************************************************************************/
 123
 124 bool claim_connection(connection_struct *conn, const char *name)
 125 {
 126         struct db_record *rec;
 127         struct connections_data crec;
 128         TDB_DATA dbuf;
 129         NTSTATUS status;
 130
 131         DEBUG(5,("claiming [%s]\n", name));
 132
 133         if (!(rec = connections_fetch_entry(talloc_tos(), conn, name))) {
 134                 DEBUG(0, ("connections_fetch_entry failed\n"));
 135                 return False;
 136         }
 137
 138         /* fill in the crec */
 139         ZERO_STRUCT(crec);
 140         crec.magic = 0x280267;
 141         crec.pid = sconn_server_id(conn->sconn);
 142         crec.cnum = conn->cnum;
 143         crec.uid = conn->server_info->utok.uid;
 144         crec.gid = conn->server_info->utok.gid;
 145         strlcpy(crec.servicename, lp_servicename(SNUM(conn)),
 146                 sizeof(crec.servicename));
 147         crec.start = time(NULL);
 148
 149         strlcpy(crec.machine,get_remote_machine_name(),sizeof(crec.machine));
 150         strlcpy(crec.addr, conn->sconn->client_id.addr, sizeof(crec.addr));
 151
 152         dbuf.dptr = (uint8 *)&crec;
 153         dbuf.dsize = sizeof(crec);
 154
 155         status = rec->store(rec, dbuf, TDB_REPLACE);
 156
 157         TALLOC_FREE(rec);
 158
 159         if (!NT_STATUS_IS_OK(status)) {
 160                 DEBUG(0,("claim_connection: tdb_store failed with error %s.\n",
 161                          nt_errstr(status)));
 162                 return False;
 163         }
 164
 165         return True;
 166 }