+/*
+ Unix SMB/CIFS implementation.
+ connection claim routines
+ Copyright (C) Andrew Tridgell 1998
+
+ This program is free software; you can redistribute it and/or modify
+ it under the terms of the GNU General Public License as published by
+ the Free Software Foundation; either version 2 of the License, or
+ (at your option) any later version.
+
+ This program is distributed in the hope that it will be useful,
+ but WITHOUT ANY WARRANTY; without even the implied warranty of
+ MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
+ GNU General Public License for more details.
+
+ You should have received a copy of the GNU General Public License
+ along with this program; if not, write to the Free Software
+ Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA.
+*/
+
+#include "includes.h"
+
+static TDB_CONTEXT *tdb;
+
+/****************************************************************************
+ Return the connection tdb context (used for message send all).
+****************************************************************************/
+
+TDB_CONTEXT *conn_tdb_ctx(void)
+{
+ if (!tdb)
+ tdb = tdb_open_log(lock_path("connections.tdb"), 0, TDB_CLEAR_IF_FIRST|TDB_DEFAULT,
+ O_RDWR | O_CREAT, 0644);
+
+ return tdb;
+}
+
+static void make_conn_key(connection_struct *conn, const char *name, TDB_DATA *pkbuf, struct connections_key *pkey)
+{
+ ZERO_STRUCTP(pkey);
+ pkey->pid = procid_self();
+ pkey->cnum = conn?conn->cnum:-1;
+ fstrcpy(pkey->name, name);
+#ifdef DEVELOPER
+ /* valgrind fixer... */
+ {
+ size_t sl = strlen(pkey->name);
+ if (sizeof(fstring)-sl)
+ memset(&pkey->name[sl], '\0', sizeof(fstring)-sl);
+ }
+#endif
+
+ pkbuf->dptr = (char *)pkey;
+ pkbuf->dsize = sizeof(*pkey);
+}
+
+/****************************************************************************
+ Delete a connection record.
+****************************************************************************/
+
+BOOL yield_connection(connection_struct *conn, const char *name)
+{
+ struct connections_key key;
+ TDB_DATA kbuf;
+
+ if (!tdb)
+ return False;
+
+ DEBUG(3,("Yielding connection to %s\n",name));
+
+ make_conn_key(conn, name, &kbuf, &key);
+
+ if (tdb_delete(tdb, kbuf) != 0) {
+ int dbg_lvl = (!conn && (tdb_error(tdb) == TDB_ERR_NOEXIST)) ? 3 : 0;
+ DEBUG(dbg_lvl,("yield_connection: tdb_delete for name %s failed with error %s.\n",
+ name, tdb_errorstr(tdb) ));
+ return (False);
+ }
+
+ return(True);
+}
+
+struct count_stat {
+ pid_t mypid;
+ int curr_connections;
+ char *name;
+ BOOL Clear;
+};
+
+/****************************************************************************
+ Count the entries belonging to a service in the connection db.
+****************************************************************************/
+
+static int count_fn( TDB_CONTEXT *the_tdb, TDB_DATA kbuf, TDB_DATA dbuf, void *udp)
+{
+ struct connections_data crec;
+ struct count_stat *cs = (struct count_stat *)udp;
+
+ if (dbuf.dsize != sizeof(crec))
+ return 0;
+
+ memcpy(&crec, dbuf.dptr, sizeof(crec));
+
+ if (crec.cnum == -1)
+ return 0;
+
+ /* If the pid was not found delete the entry from connections.tdb */
+
+ if (cs->Clear && !process_exists(crec.pid) && (errno == ESRCH)) {
+ DEBUG(2,("pid %s doesn't exist - deleting connections %d [%s]\n",
+ procid_str_static(&crec.pid), crec.cnum, crec.name));
+ if (tdb_delete(the_tdb, kbuf) != 0)
+ DEBUG(0,("count_fn: tdb_delete failed with error %s\n", tdb_errorstr(tdb) ));
+ return 0;
+ }
+
+ if (strequal(crec.name, cs->name))
+ cs->curr_connections++;
+
+ return 0;
+}
+
+/****************************************************************************
+ Claim an entry in the connections database.
+****************************************************************************/
+
+BOOL claim_connection(connection_struct *conn, const char *name,int max_connections,BOOL Clear, uint32 msg_flags)
+{
+ struct connections_key key;
+ struct connections_data crec;
+ TDB_DATA kbuf, dbuf;
+
+ if (!tdb)
+ tdb = tdb_open_log(lock_path("connections.tdb"), 0, TDB_CLEAR_IF_FIRST|TDB_DEFAULT,
+ O_RDWR | O_CREAT, 0644);
+
+ if (!tdb)
+ return False;
+
+ /*
+ * Enforce the max connections parameter.
+ */
+
+ if (max_connections > 0) {
+ struct count_stat cs;
+
+ cs.mypid = sys_getpid();
+ cs.curr_connections = 0;
+ cs.name = lp_servicename(SNUM(conn));
+ cs.Clear = Clear;
+
+ /*
+ * This has a race condition, but locking the chain before hand is worse
+ * as it leads to deadlock.
+ */
+
+ if (tdb_traverse(tdb, count_fn, &cs) == -1) {
+ DEBUG(0,("claim_connection: traverse of connections.tdb failed with error %s.\n",
+ tdb_errorstr(tdb) ));
+ return False;
+ }
+
+ if (cs.curr_connections >= max_connections) {
+ DEBUG(1,("claim_connection: Max connections (%d) exceeded for %s\n",
+ max_connections, name ));
+ return False;
+ }
+ }
+
+ DEBUG(5,("claiming %s %d\n",name,max_connections));
+
+ make_conn_key(conn, name, &kbuf, &key);
+
+ /* fill in the crec */
+ ZERO_STRUCT(crec);
+ crec.magic = 0x280267;
+ crec.pid = procid_self();
+ crec.cnum = conn?conn->cnum:-1;
+ if (conn) {
+ crec.uid = conn->uid;
+ crec.gid = conn->gid;
+ safe_strcpy(crec.name,
+ lp_servicename(SNUM(conn)),sizeof(crec.name)-1);
+ }
+ crec.start = time(NULL);
+ crec.bcast_msg_flags = msg_flags;
+
+ safe_strcpy(crec.machine,get_remote_machine_name(),sizeof(crec.machine)-1);
+ safe_strcpy(crec.addr,conn?conn->client_address:client_addr(),sizeof(crec.addr)-1);
+
+ dbuf.dptr = (char *)&crec;
+ dbuf.dsize = sizeof(crec);
+
+ if (tdb_store(tdb, kbuf, dbuf, TDB_REPLACE) != 0) {
+ DEBUG(0,("claim_connection: tdb_store failed with error %s.\n",
+ tdb_errorstr(tdb) ));
+ return False;
+ }
+
+ return True;
+}
+
+BOOL register_message_flags(BOOL doreg, uint32 msg_flags)
+{
+ struct connections_key key;
+ struct connections_data *pcrec;
+ TDB_DATA kbuf, dbuf;
+
+ if (!tdb)
+ return False;
+
+ DEBUG(10,("register_message_flags: %s flags 0x%x\n",
+ doreg ? "adding" : "removing",
+ (unsigned int)msg_flags ));
+
+ make_conn_key(NULL, "", &kbuf, &key);
+
+ dbuf = tdb_fetch(tdb, kbuf);
+ if (!dbuf.dptr) {
+ DEBUG(0,("register_message_flags: tdb_fetch failed: %s\n",
+ tdb_errorstr(tdb)));
+ return False;
+ }
+
+ pcrec = (struct connections_data *)dbuf.dptr;
+ if (doreg)
+ pcrec->bcast_msg_flags |= msg_flags;
+ else
+ pcrec->bcast_msg_flags &= ~msg_flags;
+
+ if (tdb_store(tdb, kbuf, dbuf, TDB_REPLACE) != 0) {
+ DEBUG(0,("register_message_flags: tdb_store failed: %s.\n",
+ tdb_errorstr(tdb) ));
+ SAFE_FREE(dbuf.dptr);
+ return False;
+ }
+
+ DEBUG(10,("register_message_flags: new flags 0x%x\n",
+ (unsigned int)pcrec->bcast_msg_flags ));
+
+ SAFE_FREE(dbuf.dptr);
+ return True;
+}
projects / samba / blobdiff