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
  22 /****************************************************************************
  23  Delete a connection record.
  24 ****************************************************************************/
  25
  26 bool yield_connection(connection_struct *conn, const char *name)
  27 {
  28         struct db_record *rec;
  29         NTSTATUS status;
  30
  31         DEBUG(3,("Yielding connection to %s\n",name));
  32
  33         rec = connections_fetch_entry(talloc_tos(), conn, name);
  34         if (rec == NULL) {
  35                 DEBUG(0, ("connections_fetch_entry failed\n"));
  36                 return False;
  37         }
  38
  39         status = rec->delete_rec(rec);
  40         if (!NT_STATUS_IS_OK(status)) {
  41                 DEBUG( NT_STATUS_EQUAL(status, NT_STATUS_NOT_FOUND) ? 3 : 0,
  42                        ("deleting connection record returned %s\n",
  43                         nt_errstr(status)));
  44         }
  45
  46         TALLOC_FREE(rec);
  47         return NT_STATUS_IS_OK(status);
  48 }
  49
  50 struct count_stat {
  51         int curr_connections;
  52         const char *name;
  53         bool Clear;
  54 };
  55
  56 /****************************************************************************
  57  Count the entries belonging to a service in the connection db.
  58 ****************************************************************************/
  59
  60 static int count_fn(struct db_record *rec,
  61                     const struct connections_key *ckey,
  62                     const struct connections_data *crec,
  63                     void *udp)
  64 {
  65         struct count_stat *cs = (struct count_stat *)udp;
  66
  67         if (crec->cnum == -1) {
  68                 return 0;
  69         }
  70
  71         /* If the pid was not found delete the entry from connections.tdb */
  72
  73         if (cs->Clear && !process_exists(crec->pid) && (errno == ESRCH)) {
  74                 NTSTATUS status;
  75                 DEBUG(2,("pid %s doesn't exist - deleting connections %d [%s]\n",
  76                          procid_str_static(&crec->pid), crec->cnum,
  77                          crec->servicename));
  78
  79                 status = rec->delete_rec(rec);
  80                 if (!NT_STATUS_IS_OK(status)) {
  81                         DEBUG(0,("count_fn: tdb_delete failed with error %s\n",
  82                                  nt_errstr(status)));
  83                 }
  84                 return 0;
  85         }
  86
  87         if (strequal(crec->servicename, cs->name))
  88                 cs->curr_connections++;
  89
  90         return 0;
  91 }
  92
  93 /****************************************************************************
  94  Claim an entry in the connections database.
  95 ****************************************************************************/
  96
  97 int count_current_connections( const char *sharename, bool clear  )
  98 {
  99         struct count_stat cs;
 100
 101         cs.curr_connections = 0;
 102         cs.name = sharename;
 103         cs.Clear = clear;
 104
 105         /*
 106          * This has a race condition, but locking the chain before hand is worse
 107          * as it leads to deadlock.
 108          */
 109
 110         if (connections_forall(count_fn, &cs) == -1) {
 111                 DEBUG(0,("count_current_connections: traverse of "
 112                          "connections.tdb failed\n"));
 113                 return False;
 114         }
 115
 116         return cs.curr_connections;
 117 }
 118
 119 /****************************************************************************
 120  Claim an entry in the connections database.
 121 ****************************************************************************/
 122
 123 bool claim_connection(connection_struct *conn, const char *name)
 124 {
 125         struct db_record *rec;
 126         struct connections_data crec;
 127         TDB_DATA dbuf;
 128         NTSTATUS status;
 129         char addr[INET6_ADDRSTRLEN];
 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 = procid_self();
 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?conn->client_address:
 151                         client_addr(get_client_fd(),addr,sizeof(addr)),
 152                 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 }