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         pid_t mypid;
  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.mypid = sys_getpid();
 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                       uint32 msg_flags)
 127 {
 128         struct db_record *rec;
 129         struct connections_data crec;
 130         TDB_DATA dbuf;
 131         NTSTATUS status;
 132         char addr[INET6_ADDRSTRLEN];
 133
 134         DEBUG(5,("claiming [%s]\n", name));
 135
 136         if (!(rec = connections_fetch_entry(talloc_tos(), conn, name))) {
 137                 DEBUG(0, ("connections_fetch_entry failed\n"));
 138                 return False;
 139         }
 140
 141         /* fill in the crec */
 142         ZERO_STRUCT(crec);
 143         crec.magic = 0x280267;
 144         crec.pid = procid_self();
 145         crec.cnum = conn?conn->cnum:-1;
 146         if (conn) {
 147                 crec.uid = conn->server_info->utok.uid;
 148                 crec.gid = conn->server_info->utok.gid;
 149                 strlcpy(crec.servicename, lp_servicename(SNUM(conn)),
 150                         sizeof(crec.servicename));
 151         }
 152         crec.start = time(NULL);
 153         crec.bcast_msg_flags = msg_flags;
 154
 155         strlcpy(crec.machine,get_remote_machine_name(),sizeof(crec.machine));
 156         strlcpy(crec.addr,conn?conn->client_address:
 157                         client_addr(get_client_fd(),addr,sizeof(addr)),
 158                 sizeof(crec.addr));
 159
 160         dbuf.dptr = (uint8 *)&crec;
 161         dbuf.dsize = sizeof(crec);
 162
 163         status = rec->store(rec, dbuf, TDB_REPLACE);
 164
 165         TALLOC_FREE(rec);
 166
 167         if (!NT_STATUS_IS_OK(status)) {
 168                 DEBUG(0,("claim_connection: tdb_store failed with error %s.\n",
 169                          nt_errstr(status)));
 170                 return False;
 171         }
 172
 173         return True;
 174 }
 175
 176 bool register_message_flags(bool doreg, uint32 msg_flags)
 177 {
 178         struct db_record *rec;
 179         struct connections_data *pcrec;
 180         NTSTATUS status;
 181
 182         DEBUG(10,("register_message_flags: %s flags 0x%x\n",
 183                 doreg ? "adding" : "removing",
 184                 (unsigned int)msg_flags ));
 185
 186         if (!(rec = connections_fetch_entry(NULL, NULL, ""))) {
 187                 DEBUG(0, ("connections_fetch_entry failed\n"));
 188                 return False;
 189         }
 190
 191         if (rec->value.dsize != sizeof(struct connections_data)) {
 192                 DEBUG(0,("register_message_flags: Got wrong record size\n"));
 193                 TALLOC_FREE(rec);
 194                 return False;
 195         }
 196
 197         pcrec = (struct connections_data *)rec->value.dptr;
 198         if (doreg)
 199                 pcrec->bcast_msg_flags |= msg_flags;
 200         else
 201                 pcrec->bcast_msg_flags &= ~msg_flags;
 202
 203         status = rec->store(rec, rec->value, TDB_REPLACE);
 204
 205         if (!NT_STATUS_IS_OK(status)) {
 206                 DEBUG(0,("register_message_flags: tdb_store failed: %s.\n",
 207                          nt_errstr(status)));
 208                 TALLOC_FREE(rec);
 209                 return False;
 210         }
 211
 212         DEBUG(10,("register_message_flags: new flags 0x%x\n",
 213                 (unsigned int)pcrec->bcast_msg_flags ));
 214
 215         TALLOC_FREE(rec);
 216
 217         return True;
 218 }