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 #include "dbwrap.h"
  23
  24 /****************************************************************************
  25  Delete a connection record.
  26 ****************************************************************************/
  27
  28 bool yield_connection(connection_struct *conn, const char *name)
  29 {
  30         struct db_record *rec;
  31         NTSTATUS status;
  32
  33         DEBUG(3,("Yielding connection to %s\n",name));
  34
  35         rec = connections_fetch_entry(talloc_tos(), conn, name);
  36         if (rec == NULL) {
  37                 DEBUG(0, ("connections_fetch_entry failed\n"));
  38                 return False;
  39         }
  40
  41         status = rec->delete_rec(rec);
  42         if (!NT_STATUS_IS_OK(status)) {
  43                 DEBUG( NT_STATUS_EQUAL(status, NT_STATUS_NOT_FOUND) ? 3 : 0,
  44                        ("deleting connection record returned %s\n",
  45                         nt_errstr(status)));
  46         }
  47
  48         TALLOC_FREE(rec);
  49         return NT_STATUS_IS_OK(status);
  50 }
  51
  52 struct count_stat {
  53         int curr_connections;
  54         const char *name;
  55         bool Clear;
  56 };
  57
  58 /****************************************************************************
  59  Count the entries belonging to a service in the connection db.
  60 ****************************************************************************/
  61
  62 static int count_fn(struct db_record *rec,
  63                     const struct connections_key *ckey,
  64                     const struct connections_data *crec,
  65                     void *udp)
  66 {
  67         struct count_stat *cs = (struct count_stat *)udp;
  68
  69         if (crec->cnum == -1) {
  70                 return 0;
  71         }
  72
  73         /* If the pid was not found delete the entry from connections.tdb */
  74
  75         if (cs->Clear && !process_exists(crec->pid) && (errno == ESRCH)) {
  76                 NTSTATUS status;
  77                 DEBUG(2,("pid %s doesn't exist - deleting connections %d [%s]\n",
  78                          procid_str_static(&crec->pid), crec->cnum,
  79                          crec->servicename));
  80
  81                 status = rec->delete_rec(rec);
  82                 if (!NT_STATUS_IS_OK(status)) {
  83                         DEBUG(0,("count_fn: tdb_delete failed with error %s\n",
  84                                  nt_errstr(status)));
  85                 }
  86                 return 0;
  87         }
  88
  89         if (strequal(crec->servicename, cs->name))
  90                 cs->curr_connections++;
  91
  92         return 0;
  93 }
  94
  95 /****************************************************************************
  96  Claim an entry in the connections database.
  97 ****************************************************************************/
  98
  99 int count_current_connections( const char *sharename, bool clear  )
 100 {
 101         struct count_stat cs;
 102
 103         cs.curr_connections = 0;
 104         cs.name = sharename;
 105         cs.Clear = clear;
 106
 107         /*
 108          * This has a race condition, but locking the chain before hand is worse
 109          * as it leads to deadlock.
 110          */
 111
 112         if (connections_forall(count_fn, &cs) == -1) {
 113                 DEBUG(0,("count_current_connections: traverse of "
 114                          "connections.tdb failed\n"));
 115                 return False;
 116         }
 117
 118         return cs.curr_connections;
 119 }
 120
 121 /****************************************************************************
 122  Claim an entry in the connections database.
 123 ****************************************************************************/
 124
 125 bool claim_connection(connection_struct *conn, const char *name)
 126 {
 127         struct db_record *rec;
 128         struct connections_data crec;
 129         TDB_DATA dbuf;
 130         NTSTATUS status;
 131
 132         DEBUG(5,("claiming [%s]\n", name));
 133
 134         if (!(rec = connections_fetch_entry(talloc_tos(), conn, name))) {
 135                 DEBUG(0, ("connections_fetch_entry failed\n"));
 136                 return False;
 137         }
 138
 139         /* fill in the crec */
 140         ZERO_STRUCT(crec);
 141         crec.magic = 0x280267;
 142         crec.pid = sconn_server_id(conn->sconn);
 143         crec.cnum = conn->cnum;
 144         crec.uid = conn->session_info->utok.uid;
 145         crec.gid = conn->session_info->utok.gid;
 146         strlcpy(crec.servicename, lp_servicename(SNUM(conn)),
 147                 sizeof(crec.servicename));
 148         crec.start = time(NULL);
 149
 150         strlcpy(crec.machine,get_remote_machine_name(),sizeof(crec.machine));
 151         strlcpy(crec.addr, conn->sconn->client_id.addr, sizeof(crec.addr));
 152
 153         dbuf.dptr = (uint8 *)&crec;
 154         dbuf.dsize = sizeof(crec);
 155
 156         status = rec->store(rec, dbuf, TDB_REPLACE);
 157
 158         TALLOC_FREE(rec);
 159
 160         if (!NT_STATUS_IS_OK(status)) {
 161                 DEBUG(0,("claim_connection: tdb_store failed with error %s.\n",
 162                          nt_errstr(status)));
 163                 return False;
 164         }
 165
 166         return True;
 167 }