s3: Fix a long-standing problem with recycled PIDs
[metze/samba/wip.git] / source3 / smbd / server.c
1 /*
2    Unix SMB/CIFS implementation.
3    Main SMB server routines
4    Copyright (C) Andrew Tridgell                1992-1998
5    Copyright (C) Martin Pool                    2002
6    Copyright (C) Jelmer Vernooij                2002-2003
7    Copyright (C) Volker Lendecke                1993-2007
8    Copyright (C) Jeremy Allison                 1993-2007
9
10    This program is free software; you can redistribute it and/or modify
11    it under the terms of the GNU General Public License as published by
12    the Free Software Foundation; either version 3 of the License, or
13    (at your option) any later version.
14
15    This program is distributed in the hope that it will be useful,
16    but WITHOUT ANY WARRANTY; without even the implied warranty of
17    MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
18    GNU General Public License for more details.
19
20    You should have received a copy of the GNU General Public License
21    along with this program.  If not, see <http://www.gnu.org/licenses/>.
22 */
23
24 #include "includes.h"
25 #include "smbd/globals.h"
26
27 static_decl_rpc;
28
29 #ifdef WITH_DFS
30 extern int dcelogin_atmost_once;
31 #endif /* WITH_DFS */
32
33 int smbd_server_fd(void)
34 {
35         return server_fd;
36 }
37
38 static void smbd_set_server_fd(int fd)
39 {
40         server_fd = fd;
41 }
42
43 int get_client_fd(void)
44 {
45         return server_fd;
46 }
47
48 struct event_context *smbd_event_context(void)
49 {
50         if (!smbd_event_ctx) {
51                 smbd_event_ctx = event_context_init(talloc_autofree_context());
52         }
53         if (!smbd_event_ctx) {
54                 smb_panic("Could not init smbd event context");
55         }
56         return smbd_event_ctx;
57 }
58
59 struct messaging_context *smbd_messaging_context(void)
60 {
61         if (smbd_msg_ctx == NULL) {
62                 smbd_msg_ctx = messaging_init(talloc_autofree_context(),
63                                               procid_self(),
64                                               smbd_event_context());
65         }
66         if (smbd_msg_ctx == NULL) {
67                 DEBUG(0, ("Could not init smbd messaging context.\n"));
68         }
69         return smbd_msg_ctx;
70 }
71
72 struct memcache *smbd_memcache(void)
73 {
74         if (!smbd_memcache_ctx) {
75                 smbd_memcache_ctx = memcache_init(talloc_autofree_context(),
76                                                   lp_max_stat_cache_size()*1024);
77         }
78         if (!smbd_memcache_ctx) {
79                 smb_panic("Could not init smbd memcache");
80         }
81
82         return smbd_memcache_ctx;
83 }
84
85 /*******************************************************************
86  What to do when smb.conf is updated.
87  ********************************************************************/
88
89 static void smb_conf_updated(struct messaging_context *msg,
90                              void *private_data,
91                              uint32_t msg_type,
92                              struct server_id server_id,
93                              DATA_BLOB *data)
94 {
95         DEBUG(10,("smb_conf_updated: Got message saying smb.conf was "
96                   "updated. Reloading.\n"));
97         change_to_root_user();
98         reload_services(False);
99 }
100
101
102 /*******************************************************************
103  Delete a statcache entry.
104  ********************************************************************/
105
106 static void smb_stat_cache_delete(struct messaging_context *msg,
107                                   void *private_data,
108                                   uint32_t msg_tnype,
109                                   struct server_id server_id,
110                                   DATA_BLOB *data)
111 {
112         const char *name = (const char *)data->data;
113         DEBUG(10,("smb_stat_cache_delete: delete name %s\n", name));
114         stat_cache_delete(name);
115 }
116
117 /****************************************************************************
118   Send a SIGTERM to our process group.
119 *****************************************************************************/
120
121 static void  killkids(void)
122 {
123         if(am_parent) kill(0,SIGTERM);
124 }
125
126 /****************************************************************************
127  Process a sam sync message - not sure whether to do this here or
128  somewhere else.
129 ****************************************************************************/
130
131 static void msg_sam_sync(struct messaging_context *msg,
132                          void *private_data,
133                          uint32_t msg_type,
134                          struct server_id server_id,
135                          DATA_BLOB *data)
136 {
137         DEBUG(10, ("** sam sync message received, ignoring\n"));
138 }
139
140 static void msg_exit_server(struct messaging_context *msg,
141                             void *private_data,
142                             uint32_t msg_type,
143                             struct server_id server_id,
144                             DATA_BLOB *data)
145 {
146         DEBUG(3, ("got a SHUTDOWN message\n"));
147         exit_server_cleanly(NULL);
148 }
149
150 #ifdef DEVELOPER
151 static void msg_inject_fault(struct messaging_context *msg,
152                              void *private_data,
153                              uint32_t msg_type,
154                              struct server_id src,
155                              DATA_BLOB *data)
156 {
157         int sig;
158
159         if (data->length != sizeof(sig)) {
160                 
161                 DEBUG(0, ("Process %s sent bogus signal injection request\n",
162                           procid_str_static(&src)));
163                 return;
164         }
165
166         sig = *(int *)data->data;
167         if (sig == -1) {
168                 exit_server("internal error injected");
169                 return;
170         }
171
172 #if HAVE_STRSIGNAL
173         DEBUG(0, ("Process %s requested injection of signal %d (%s)\n",
174                   procid_str_static(&src), sig, strsignal(sig)));
175 #else
176         DEBUG(0, ("Process %s requested injection of signal %d\n",
177                   procid_str_static(&src), sig));
178 #endif
179
180         kill(sys_getpid(), sig);
181 }
182 #endif /* DEVELOPER */
183
184 /*
185  * Parent smbd process sets its own debug level first and then
186  * sends a message to all the smbd children to adjust their debug
187  * level to that of the parent.
188  */
189
190 static void smbd_msg_debug(struct messaging_context *msg_ctx,
191                            void *private_data,
192                            uint32_t msg_type,
193                            struct server_id server_id,
194                            DATA_BLOB *data)
195 {
196         struct child_pid *child;
197
198         debug_message(msg_ctx, private_data, MSG_DEBUG, server_id, data);
199
200         for (child = children; child != NULL; child = child->next) {
201                 messaging_send_buf(msg_ctx, pid_to_procid(child->pid),
202                                    MSG_DEBUG,
203                                    data->data,
204                                    strlen((char *) data->data) + 1);
205         }
206 }
207
208 static void add_child_pid(pid_t pid)
209 {
210         struct child_pid *child;
211
212         child = SMB_MALLOC_P(struct child_pid);
213         if (child == NULL) {
214                 DEBUG(0, ("Could not add child struct -- malloc failed\n"));
215                 return;
216         }
217         child->pid = pid;
218         DLIST_ADD(children, child);
219         num_children += 1;
220 }
221
222 /*
223   at most every smbd:cleanuptime seconds (default 20), we scan the BRL
224   and locking database for entries to cleanup. As a side effect this
225   also cleans up dead entries in the connections database (due to the
226   traversal in message_send_all()
227
228   Using a timer for this prevents a flood of traversals when a large
229   number of clients disconnect at the same time (perhaps due to a
230   network outage).  
231 */
232
233 static void cleanup_timeout_fn(struct event_context *event_ctx,
234                                 struct timed_event *te,
235                                 struct timeval now,
236                                 void *private_data)
237 {
238         struct timed_event **cleanup_te = (struct timed_event **)private_data;
239
240         DEBUG(1,("Cleaning up brl and lock database after unclean shutdown\n"));
241         message_send_all(smbd_messaging_context(), MSG_SMB_UNLOCK, NULL, 0, NULL);
242         messaging_send_buf(smbd_messaging_context(), procid_self(),
243                                 MSG_SMB_BRL_VALIDATE, NULL, 0);
244         /* mark the cleanup as having been done */
245         (*cleanup_te) = NULL;
246 }
247
248 static void remove_child_pid(pid_t pid, bool unclean_shutdown)
249 {
250         struct child_pid *child;
251         static struct timed_event *cleanup_te;
252         struct server_id child_id;
253
254         if (unclean_shutdown) {
255                 /* a child terminated uncleanly so tickle all
256                    processes to see if they can grab any of the
257                    pending locks
258                 */
259                 DEBUG(3,(__location__ " Unclean shutdown of pid %u\n",
260                         (unsigned int)pid));
261                 if (!cleanup_te) {
262                         /* call the cleanup timer, but not too often */
263                         int cleanup_time = lp_parm_int(-1, "smbd", "cleanuptime", 20);
264                         cleanup_te = event_add_timed(smbd_event_context(), NULL,
265                                                 timeval_current_ofs(cleanup_time, 0),
266                                                 cleanup_timeout_fn,
267                                                 &cleanup_te);
268                         DEBUG(1,("Scheduled cleanup of brl and lock database after unclean shutdown\n"));
269                 }
270         }
271
272         child_id = procid_self(); /* Just initialize pid and potentially vnn */
273         child_id.pid = pid;
274
275         if (!serverid_deregister(&child_id)) {
276                 DEBUG(1, ("Could not remove pid %d from serverid.tdb\n",
277                           (int)pid));
278         }
279
280         for (child = children; child != NULL; child = child->next) {
281                 if (child->pid == pid) {
282                         struct child_pid *tmp = child;
283                         DLIST_REMOVE(children, child);
284                         SAFE_FREE(tmp);
285                         num_children -= 1;
286                         return;
287                 }
288         }
289
290         DEBUG(0, ("Could not find child %d -- ignoring\n", (int)pid));
291 }
292
293 /****************************************************************************
294  Have we reached the process limit ?
295 ****************************************************************************/
296
297 static bool allowable_number_of_smbd_processes(void)
298 {
299         int max_processes = lp_max_smbd_processes();
300
301         if (!max_processes)
302                 return True;
303
304         return num_children < max_processes;
305 }
306
307 static void smbd_sig_chld_handler(struct tevent_context *ev,
308                                   struct tevent_signal *se,
309                                   int signum,
310                                   int count,
311                                   void *siginfo,
312                                   void *private_data)
313 {
314         pid_t pid;
315         int status;
316
317         while ((pid = sys_waitpid(-1, &status, WNOHANG)) > 0) {
318                 bool unclean_shutdown = False;
319
320                 /* If the child terminated normally, assume
321                    it was an unclean shutdown unless the
322                    status is 0
323                 */
324                 if (WIFEXITED(status)) {
325                         unclean_shutdown = WEXITSTATUS(status);
326                 }
327                 /* If the child terminated due to a signal
328                    we always assume it was unclean.
329                 */
330                 if (WIFSIGNALED(status)) {
331                         unclean_shutdown = True;
332                 }
333                 remove_child_pid(pid, unclean_shutdown);
334         }
335 }
336
337 static void smbd_setup_sig_chld_handler(void)
338 {
339         struct tevent_signal *se;
340
341         se = tevent_add_signal(smbd_event_context(),
342                                smbd_event_context(),
343                                SIGCHLD, 0,
344                                smbd_sig_chld_handler,
345                                NULL);
346         if (!se) {
347                 exit_server("failed to setup SIGCHLD handler");
348         }
349 }
350
351 struct smbd_open_socket;
352
353 struct smbd_parent_context {
354         bool interactive;
355
356         /* the list of listening sockets */
357         struct smbd_open_socket *sockets;
358 };
359
360 struct smbd_open_socket {
361         struct smbd_open_socket *prev, *next;
362         struct smbd_parent_context *parent;
363         int fd;
364         struct tevent_fd *fde;
365 };
366
367 static void smbd_open_socket_close_fn(struct tevent_context *ev,
368                                       struct tevent_fd *fde,
369                                       int fd,
370                                       void *private_data)
371 {
372         /* this might be the socket_wrapper swrap_close() */
373         close(fd);
374 }
375
376 static void smbd_accept_connection(struct tevent_context *ev,
377                                    struct tevent_fd *fde,
378                                    uint16_t flags,
379                                    void *private_data)
380 {
381         struct smbd_open_socket *s = talloc_get_type_abort(private_data,
382                                      struct smbd_open_socket);
383         struct sockaddr_storage addr;
384         socklen_t in_addrlen = sizeof(addr);
385         pid_t pid = 0;
386         uint64_t unique_id;
387
388         smbd_set_server_fd(accept(s->fd,(struct sockaddr *)&addr,&in_addrlen));
389
390         if (smbd_server_fd() == -1 && errno == EINTR)
391                 return;
392
393         if (smbd_server_fd() == -1) {
394                 DEBUG(0,("open_sockets_smbd: accept: %s\n",
395                          strerror(errno)));
396                 return;
397         }
398
399         if (s->parent->interactive) {
400                 smbd_process();
401                 exit_server_cleanly("end of interactive mode");
402                 return;
403         }
404
405         if (!allowable_number_of_smbd_processes()) {
406                 close(smbd_server_fd());
407                 smbd_set_server_fd(-1);
408                 return;
409         }
410
411         /*
412          * Generate a unique id in the parent process so that we use
413          * the global random state in the parent.
414          */
415         generate_random_buffer((uint8_t *)&unique_id, sizeof(unique_id));
416
417         pid = sys_fork();
418         if (pid == 0) {
419                 NTSTATUS status = NT_STATUS_OK;
420
421                 /* Child code ... */
422                 am_parent = 0;
423
424                 set_my_unique_id(unique_id);
425
426                 /* Stop zombies, the parent explicitly handles
427                  * them, counting worker smbds. */
428                 CatchChild();
429
430                 /* close our standard file
431                    descriptors */
432                 close_low_fds(False);
433
434                 /*
435                  * Can't use TALLOC_FREE here. Nulling out the argument to it
436                  * would overwrite memory we've just freed.
437                  */
438                 talloc_free(s->parent);
439                 s = NULL;
440
441                 status = reinit_after_fork(smbd_messaging_context(),
442                                            smbd_event_context(), true);
443                 if (!NT_STATUS_IS_OK(status)) {
444                         if (NT_STATUS_EQUAL(status,
445                                             NT_STATUS_TOO_MANY_OPENED_FILES)) {
446                                 DEBUG(0,("child process cannot initialize "
447                                          "because too many files are open\n"));
448                                 goto exit;
449                         }
450                         DEBUG(0,("reinit_after_fork() failed\n"));
451                         smb_panic("reinit_after_fork() failed");
452                 }
453
454                 smbd_setup_sig_term_handler();
455                 smbd_setup_sig_hup_handler();
456
457                 if (!serverid_register_self(FLAG_MSG_GENERAL|FLAG_MSG_SMBD
458                                             |FLAG_MSG_DBWRAP
459                                             |FLAG_MSG_PRINT_GENERAL)) {
460                         exit_server_cleanly("Could not register myself in "
461                                             "serverid.tdb");
462                 }
463
464                 smbd_process();
465          exit:
466                 exit_server_cleanly("end of child");
467                 return;
468         } else if (pid < 0) {
469                 DEBUG(0,("smbd_accept_connection: sys_fork() failed: %s\n",
470                          strerror(errno)));
471         }
472
473         /* The parent doesn't need this socket */
474         close(smbd_server_fd());
475
476         /* Sun May 6 18:56:14 2001 ackley@cs.unm.edu:
477                 Clear the closed fd info out of server_fd --
478                 and more importantly, out of client_fd in
479                 util_sock.c, to avoid a possible
480                 getpeername failure if we reopen the logs
481                 and use %I in the filename.
482         */
483
484         smbd_set_server_fd(-1);
485
486         if (pid != 0) {
487                 add_child_pid(pid);
488         }
489
490         /* Force parent to check log size after
491          * spawning child.  Fix from
492          * klausr@ITAP.Physik.Uni-Stuttgart.De.  The
493          * parent smbd will log to logserver.smb.  It
494          * writes only two messages for each child
495          * started/finished. But each child writes,
496          * say, 50 messages also in logserver.smb,
497          * begining with the debug_count of the
498          * parent, before the child opens its own log
499          * file logserver.client. In a worst case
500          * scenario the size of logserver.smb would be
501          * checked after about 50*50=2500 messages
502          * (ca. 100kb).
503          * */
504         force_check_log_size();
505 }
506
507 static bool smbd_open_one_socket(struct smbd_parent_context *parent,
508                                  const struct sockaddr_storage *ifss,
509                                  uint16_t port)
510 {
511         struct smbd_open_socket *s;
512
513         s = talloc(parent, struct smbd_open_socket);
514         if (!s) {
515                 return false;
516         }
517
518         s->parent = parent;
519         s->fd = open_socket_in(SOCK_STREAM,
520                                port,
521                                parent->sockets == NULL ? 0 : 2,
522                                ifss,
523                                true);
524         if (s->fd == -1) {
525                 DEBUG(0,("smbd_open_once_socket: open_socket_in: "
526                         "%s\n", strerror(errno)));
527                 TALLOC_FREE(s);
528                 /*
529                  * We ignore an error here, as we've done before
530                  */
531                 return true;
532         }
533
534         /* ready to listen */
535         set_socket_options(s->fd, "SO_KEEPALIVE");
536         set_socket_options(s->fd, lp_socket_options());
537
538         /* Set server socket to
539          * non-blocking for the accept. */
540         set_blocking(s->fd, False);
541
542         if (listen(s->fd, SMBD_LISTEN_BACKLOG) == -1) {
543                 DEBUG(0,("open_sockets_smbd: listen: "
544                         "%s\n", strerror(errno)));
545                         close(s->fd);
546                 TALLOC_FREE(s);
547                 return false;
548         }
549
550         s->fde = tevent_add_fd(smbd_event_context(),
551                                s,
552                                s->fd, TEVENT_FD_READ,
553                                smbd_accept_connection,
554                                s);
555         if (!s->fde) {
556                 DEBUG(0,("open_sockets_smbd: "
557                          "tevent_add_fd: %s\n",
558                          strerror(errno)));
559                 close(s->fd);
560                 TALLOC_FREE(s);
561                 return false;
562         }
563         tevent_fd_set_close_fn(s->fde, smbd_open_socket_close_fn);
564
565         DLIST_ADD_END(parent->sockets, s, struct smbd_open_socket *);
566
567         return true;
568 }
569
570 /****************************************************************************
571  Open the socket communication.
572 ****************************************************************************/
573
574 static bool open_sockets_smbd(struct smbd_parent_context *parent,
575                               const char *smb_ports)
576 {
577         int num_interfaces = iface_count();
578         int i;
579         char *ports;
580         unsigned dns_port = 0;
581
582 #ifdef HAVE_ATEXIT
583         atexit(killkids);
584 #endif
585
586         /* Stop zombies */
587         smbd_setup_sig_chld_handler();
588
589         /* use a reasonable default set of ports - listing on 445 and 139 */
590         if (!smb_ports) {
591                 ports = lp_smb_ports();
592                 if (!ports || !*ports) {
593                         ports = talloc_strdup(talloc_tos(), SMB_PORTS);
594                 } else {
595                         ports = talloc_strdup(talloc_tos(), ports);
596                 }
597         } else {
598                 ports = talloc_strdup(talloc_tos(), smb_ports);
599         }
600
601         if (lp_interfaces() && lp_bind_interfaces_only()) {
602                 /* We have been given an interfaces line, and been
603                    told to only bind to those interfaces. Create a
604                    socket per interface and bind to only these.
605                 */
606
607                 /* Now open a listen socket for each of the
608                    interfaces. */
609                 for(i = 0; i < num_interfaces; i++) {
610                         const struct sockaddr_storage *ifss =
611                                         iface_n_sockaddr_storage(i);
612                         char *tok;
613                         const char *ptr;
614
615                         if (ifss == NULL) {
616                                 DEBUG(0,("open_sockets_smbd: "
617                                         "interface %d has NULL IP address !\n",
618                                         i));
619                                 continue;
620                         }
621
622                         for (ptr=ports;
623                              next_token_talloc(talloc_tos(),&ptr, &tok, " \t,");) {
624                                 unsigned port = atoi(tok);
625                                 if (port == 0 || port > 0xffff) {
626                                         continue;
627                                 }
628
629                                 if (!smbd_open_one_socket(parent, ifss, port)) {
630                                         return false;
631                                 }
632                         }
633                 }
634         } else {
635                 /* Just bind to 0.0.0.0 - accept connections
636                    from anywhere. */
637
638                 char *tok;
639                 const char *ptr;
640                 const char *sock_addr = lp_socket_address();
641                 char *sock_tok;
642                 const char *sock_ptr;
643
644                 if (strequal(sock_addr, "0.0.0.0") ||
645                     strequal(sock_addr, "::")) {
646 #if HAVE_IPV6
647                         sock_addr = "::,0.0.0.0";
648 #else
649                         sock_addr = "0.0.0.0";
650 #endif
651                 }
652
653                 for (sock_ptr=sock_addr;
654                      next_token_talloc(talloc_tos(), &sock_ptr, &sock_tok, " \t,"); ) {
655                         for (ptr=ports; next_token_talloc(talloc_tos(), &ptr, &tok, " \t,"); ) {
656                                 struct sockaddr_storage ss;
657
658                                 unsigned port = atoi(tok);
659                                 if (port == 0 || port > 0xffff) {
660                                         continue;
661                                 }
662
663                                 /* Keep the first port for mDNS service
664                                  * registration.
665                                  */
666                                 if (dns_port == 0) {
667                                         dns_port = port;
668                                 }
669
670                                 /* open an incoming socket */
671                                 if (!interpret_string_addr(&ss, sock_tok,
672                                                 AI_NUMERICHOST|AI_PASSIVE)) {
673                                         continue;
674                                 }
675
676                                 if (!smbd_open_one_socket(parent, &ss, port)) {
677                                         return false;
678                                 }
679                         }
680                 }
681         }
682
683         if (parent->sockets == NULL) {
684                 DEBUG(0,("open_sockets_smbd: No "
685                         "sockets available to bind to.\n"));
686                 return false;
687         }
688
689         /* Setup the main smbd so that we can get messages. Note that
690            do this after starting listening. This is needed as when in
691            clustered mode, ctdb won't allow us to start doing database
692            operations until it has gone thru a full startup, which
693            includes checking to see that smbd is listening. */
694
695         if (!serverid_register_self(FLAG_MSG_GENERAL|FLAG_MSG_SMBD
696                                     |FLAG_MSG_DBWRAP)) {
697                 DEBUG(0, ("open_sockets_smbd: Failed to register "
698                           "myself in serverid.tdb\n"));
699                 return false;
700         }
701
702         /* Listen to messages */
703
704         messaging_register(smbd_messaging_context(), NULL,
705                            MSG_SMB_SAM_SYNC, msg_sam_sync);
706         messaging_register(smbd_messaging_context(), NULL,
707                            MSG_SHUTDOWN, msg_exit_server);
708         messaging_register(smbd_messaging_context(), NULL,
709                            MSG_SMB_FILE_RENAME, msg_file_was_renamed);
710         messaging_register(smbd_messaging_context(), NULL,
711                            MSG_SMB_CONF_UPDATED, smb_conf_updated);
712         messaging_register(smbd_messaging_context(), NULL,
713                            MSG_SMB_STAT_CACHE_DELETE, smb_stat_cache_delete);
714         messaging_register(smbd_messaging_context(), NULL,
715                            MSG_DEBUG, smbd_msg_debug);
716         brl_register_msgs(smbd_messaging_context());
717
718 #ifdef CLUSTER_SUPPORT
719         if (lp_clustering()) {
720                 ctdbd_register_reconfigure(messaging_ctdbd_connection());
721         }
722 #endif
723
724 #ifdef DEVELOPER
725         messaging_register(smbd_messaging_context(), NULL,
726                            MSG_SMB_INJECT_FAULT, msg_inject_fault);
727 #endif
728
729         if (dns_port != 0) {
730 #ifdef WITH_DNSSD_SUPPORT
731                 smbd_setup_mdns_registration(smbd_event_context(),
732                                              parent, dns_port);
733 #endif
734 #ifdef WITH_AVAHI_SUPPORT
735                 void *avahi_conn;
736
737                 avahi_conn = avahi_start_register(
738                         smbd_event_context(), smbd_event_context(), dns_port);
739                 if (avahi_conn == NULL) {
740                         DEBUG(10, ("avahi_start_register failed\n"));
741                 }
742 #endif
743         }
744
745         return true;
746 }
747
748 static void smbd_parent_loop(struct smbd_parent_context *parent)
749 {
750         /* now accept incoming connections - forking a new process
751            for each incoming connection */
752         DEBUG(2,("waiting for connections\n"));
753         while (1) {
754                 int ret;
755                 TALLOC_CTX *frame = talloc_stackframe();
756
757                 ret = tevent_loop_once(smbd_event_context());
758                 if (ret != 0) {
759                         exit_server_cleanly("tevent_loop_once() error");
760                 }
761
762                 TALLOC_FREE(frame);
763         } /* end while 1 */
764
765 /* NOTREACHED   return True; */
766 }
767
768 /****************************************************************************
769  Reload printers
770 **************************************************************************/
771 void reload_printers(void)
772 {
773         int snum;
774         int n_services = lp_numservices();
775         int pnum = lp_servicenumber(PRINTERS_NAME);
776         const char *pname;
777
778         pcap_cache_reload();
779
780         /* remove stale printers */
781         for (snum = 0; snum < n_services; snum++) {
782                 /* avoid removing PRINTERS_NAME or non-autoloaded printers */
783                 if (snum == pnum || !(lp_snum_ok(snum) && lp_print_ok(snum) &&
784                                       lp_autoloaded(snum)))
785                         continue;
786
787                 pname = lp_printername(snum);
788                 if (!pcap_printername_ok(pname)) {
789                         DEBUG(3, ("removing stale printer %s\n", pname));
790
791                         if (is_printer_published(NULL, snum, NULL))
792                                 nt_printer_publish(NULL, snum, DSPRINT_UNPUBLISH);
793                         del_a_printer(pname);
794                         lp_killservice(snum);
795                 }
796         }
797
798         load_printers();
799 }
800
801 /****************************************************************************
802  Reload the services file.
803 **************************************************************************/
804
805 bool reload_services(bool test)
806 {
807         bool ret;
808
809         if (lp_loaded()) {
810                 char *fname = lp_configfile();
811                 if (file_exist(fname) &&
812                     !strcsequal(fname, get_dyn_CONFIGFILE())) {
813                         set_dyn_CONFIGFILE(fname);
814                         test = False;
815                 }
816         }
817
818         reopen_logs();
819
820         if (test && !lp_file_list_changed())
821                 return(True);
822
823         lp_killunused(conn_snum_used);
824
825         ret = lp_load(get_dyn_CONFIGFILE(), False, False, True, True);
826
827         reload_printers();
828
829         /* perhaps the config filename is now set */
830         if (!test)
831                 reload_services(True);
832
833         reopen_logs();
834
835         load_interfaces();
836
837         if (smbd_server_fd() != -1) {
838                 set_socket_options(smbd_server_fd(),"SO_KEEPALIVE");
839                 set_socket_options(smbd_server_fd(), lp_socket_options());
840         }
841
842         mangle_reset_cache();
843         reset_stat_cache();
844
845         /* this forces service parameters to be flushed */
846         set_current_service(NULL,0,True);
847
848         return(ret);
849 }
850
851 /****************************************************************************
852  Exit the server.
853 ****************************************************************************/
854
855 /* Reasons for shutting down a server process. */
856 enum server_exit_reason { SERVER_EXIT_NORMAL, SERVER_EXIT_ABNORMAL };
857
858 static void exit_server_common(enum server_exit_reason how,
859         const char *const reason) _NORETURN_;
860
861 static void exit_server_common(enum server_exit_reason how,
862         const char *const reason)
863 {
864         bool had_open_conn = false;
865         struct smbd_server_connection *sconn = smbd_server_conn;
866
867         if (!exit_firsttime)
868                 exit(0);
869         exit_firsttime = false;
870
871         change_to_root_user();
872
873         if (sconn && sconn->smb1.negprot.auth_context) {
874                 struct auth_context *a = sconn->smb1.negprot.auth_context;
875                 a->free(&sconn->smb1.negprot.auth_context);
876         }
877
878         if (sconn) {
879                 had_open_conn = conn_close_all(sconn);
880                 invalidate_all_vuids(sconn);
881         }
882
883         /* 3 second timeout. */
884         print_notify_send_messages(smbd_messaging_context(), 3);
885
886         /* delete our entry in the serverid database. */
887         serverid_deregister_self();
888
889 #ifdef WITH_DFS
890         if (dcelogin_atmost_once) {
891                 dfs_unlogin();
892         }
893 #endif
894
895 #ifdef USE_DMAPI
896         /* Destroy Samba DMAPI session only if we are master smbd process */
897         if (am_parent) {
898                 if (!dmapi_destroy_session()) {
899                         DEBUG(0,("Unable to close Samba DMAPI session\n"));
900                 }
901         }
902 #endif
903
904         locking_end();
905         printing_end();
906
907         /*
908          * we need to force the order of freeing the following,
909          * because smbd_msg_ctx is not a talloc child of smbd_server_conn.
910          */
911         sconn = NULL;
912         TALLOC_FREE(smbd_server_conn);
913         TALLOC_FREE(smbd_msg_ctx);
914         TALLOC_FREE(smbd_event_ctx);
915
916         if (how != SERVER_EXIT_NORMAL) {
917                 int oldlevel = DEBUGLEVEL;
918
919                 DEBUGLEVEL = 10;
920
921                 DEBUGSEP(0);
922                 DEBUG(0,("Abnormal server exit: %s\n",
923                         reason ? reason : "no explanation provided"));
924                 DEBUGSEP(0);
925
926                 log_stack_trace();
927
928                 DEBUGLEVEL = oldlevel;
929                 dump_core();
930
931         } else {    
932                 DEBUG(3,("Server exit (%s)\n",
933                         (reason ? reason : "normal exit")));
934                 if (am_parent) {
935                         pidfile_unlink();
936                 }
937                 gencache_stabilize();
938         }
939
940         /* if we had any open SMB connections when we exited then we
941            need to tell the parent smbd so that it can trigger a retry
942            of any locks we may have been holding or open files we were
943            blocking */
944         if (had_open_conn) {
945                 exit(1);
946         } else {
947                 exit(0);
948         }
949 }
950
951 void exit_server(const char *const explanation)
952 {
953         exit_server_common(SERVER_EXIT_ABNORMAL, explanation);
954 }
955
956 void exit_server_cleanly(const char *const explanation)
957 {
958         exit_server_common(SERVER_EXIT_NORMAL, explanation);
959 }
960
961 void exit_server_fault(void)
962 {
963         exit_server("critical server fault");
964 }
965
966 /****************************************************************************
967  Initialise connect, service and file structs.
968 ****************************************************************************/
969
970 static bool init_structs(void )
971 {
972         /*
973          * Set the machine NETBIOS name if not already
974          * set from the config file.
975          */
976
977         if (!init_names())
978                 return False;
979
980         file_init();
981
982         if (!secrets_init())
983                 return False;
984
985         return True;
986 }
987
988 /****************************************************************************
989  main program.
990 ****************************************************************************/
991
992 /* Declare prototype for build_options() to avoid having to run it through
993    mkproto.h.  Mixing $(builddir) and $(srcdir) source files in the current
994    prototype generation system is too complicated. */
995
996 extern void build_options(bool screen);
997
998  int main(int argc,const char *argv[])
999 {
1000         /* shall I run as a daemon */
1001         bool is_daemon = false;
1002         bool interactive = false;
1003         bool Fork = true;
1004         bool no_process_group = false;
1005         bool log_stdout = false;
1006         char *ports = NULL;
1007         char *profile_level = NULL;
1008         int opt;
1009         poptContext pc;
1010         bool print_build_options = False;
1011         enum {
1012                 OPT_DAEMON = 1000,
1013                 OPT_INTERACTIVE,
1014                 OPT_FORK,
1015                 OPT_NO_PROCESS_GROUP,
1016                 OPT_LOG_STDOUT
1017         };
1018         struct poptOption long_options[] = {
1019         POPT_AUTOHELP
1020         {"daemon", 'D', POPT_ARG_NONE, NULL, OPT_DAEMON, "Become a daemon (default)" },
1021         {"interactive", 'i', POPT_ARG_NONE, NULL, OPT_INTERACTIVE, "Run interactive (not a daemon)"},
1022         {"foreground", 'F', POPT_ARG_NONE, NULL, OPT_FORK, "Run daemon in foreground (for daemontools, etc.)" },
1023         {"no-process-group", '\0', POPT_ARG_NONE, NULL, OPT_NO_PROCESS_GROUP, "Don't create a new process group" },
1024         {"log-stdout", 'S', POPT_ARG_NONE, NULL, OPT_LOG_STDOUT, "Log to stdout" },
1025         {"build-options", 'b', POPT_ARG_NONE, NULL, 'b', "Print build options" },
1026         {"port", 'p', POPT_ARG_STRING, &ports, 0, "Listen on the specified ports"},
1027         {"profiling-level", 'P', POPT_ARG_STRING, &profile_level, 0, "Set profiling level","PROFILE_LEVEL"},
1028         POPT_COMMON_SAMBA
1029         POPT_COMMON_DYNCONFIG
1030         POPT_TABLEEND
1031         };
1032         struct smbd_parent_context *parent = NULL;
1033         TALLOC_CTX *frame = talloc_stackframe(); /* Setup tos. */
1034
1035         smbd_init_globals();
1036
1037         TimeInit();
1038
1039 #ifdef HAVE_SET_AUTH_PARAMETERS
1040         set_auth_parameters(argc,argv);
1041 #endif
1042
1043         pc = poptGetContext("smbd", argc, argv, long_options, 0);
1044         while((opt = poptGetNextOpt(pc)) != -1) {
1045                 switch (opt)  {
1046                 case OPT_DAEMON:
1047                         is_daemon = true;
1048                         break;
1049                 case OPT_INTERACTIVE:
1050                         interactive = true;
1051                         break;
1052                 case OPT_FORK:
1053                         Fork = false;
1054                         break;
1055                 case OPT_NO_PROCESS_GROUP:
1056                         no_process_group = true;
1057                         break;
1058                 case OPT_LOG_STDOUT:
1059                         log_stdout = true;
1060                         break;
1061                 case 'b':
1062                         print_build_options = True;
1063                         break;
1064                 default:
1065                         d_fprintf(stderr, "\nInvalid option %s: %s\n\n",
1066                                   poptBadOption(pc, 0), poptStrerror(opt));
1067                         poptPrintUsage(pc, stderr, 0);
1068                         exit(1);
1069                 }
1070         }
1071         poptFreeContext(pc);
1072
1073         if (interactive) {
1074                 Fork = False;
1075                 log_stdout = True;
1076         }
1077
1078         setup_logging(argv[0],log_stdout);
1079
1080         if (print_build_options) {
1081                 build_options(True); /* Display output to screen as well as debug */
1082                 exit(0);
1083         }
1084
1085         load_case_tables();
1086
1087 #ifdef HAVE_SETLUID
1088         /* needed for SecureWare on SCO */
1089         setluid(0);
1090 #endif
1091
1092         sec_init();
1093
1094         set_remote_machine_name("smbd", False);
1095
1096         if (interactive && (DEBUGLEVEL >= 9)) {
1097                 talloc_enable_leak_report();
1098         }
1099
1100         if (log_stdout && Fork) {
1101                 DEBUG(0,("ERROR: Can't log to stdout (-S) unless daemon is in foreground (-F) or interactive (-i)\n"));
1102                 exit(1);
1103         }
1104
1105         /* we want to re-seed early to prevent time delays causing
1106            client problems at a later date. (tridge) */
1107         generate_random_buffer(NULL, 0);
1108
1109         /* make absolutely sure we run as root - to handle cases where people
1110            are crazy enough to have it setuid */
1111
1112         gain_root_privilege();
1113         gain_root_group_privilege();
1114
1115         fault_setup((void (*)(void *))exit_server_fault);
1116         dump_core_setup("smbd");
1117
1118         /* we are never interested in SIGPIPE */
1119         BlockSignals(True,SIGPIPE);
1120
1121 #if defined(SIGFPE)
1122         /* we are never interested in SIGFPE */
1123         BlockSignals(True,SIGFPE);
1124 #endif
1125
1126 #if defined(SIGUSR2)
1127         /* We are no longer interested in USR2 */
1128         BlockSignals(True,SIGUSR2);
1129 #endif
1130
1131         /* POSIX demands that signals are inherited. If the invoking process has
1132          * these signals masked, we will have problems, as we won't recieve them. */
1133         BlockSignals(False, SIGHUP);
1134         BlockSignals(False, SIGUSR1);
1135         BlockSignals(False, SIGTERM);
1136
1137         /* Ensure we leave no zombies until we
1138          * correctly set up child handling below. */
1139
1140         CatchChild();
1141
1142         /* we want total control over the permissions on created files,
1143            so set our umask to 0 */
1144         umask(0);
1145
1146         init_sec_ctx();
1147
1148         reopen_logs();
1149
1150         DEBUG(0,("smbd version %s started.\n", samba_version_string()));
1151         DEBUGADD(0,("%s\n", COPYRIGHT_STARTUP_MESSAGE));
1152
1153         DEBUG(2,("uid=%d gid=%d euid=%d egid=%d\n",
1154                  (int)getuid(),(int)getgid(),(int)geteuid(),(int)getegid()));
1155
1156         /* Output the build options to the debug log */ 
1157         build_options(False);
1158
1159         if (sizeof(uint16) < 2 || sizeof(uint32) < 4) {
1160                 DEBUG(0,("ERROR: Samba is not configured correctly for the word size on your machine\n"));
1161                 exit(1);
1162         }
1163
1164         if (!lp_load_initial_only(get_dyn_CONFIGFILE())) {
1165                 DEBUG(0, ("error opening config file\n"));
1166                 exit(1);
1167         }
1168
1169         if (smbd_messaging_context() == NULL)
1170                 exit(1);
1171
1172         if (!reload_services(False))
1173                 return(-1);     
1174
1175         init_structs();
1176
1177 #ifdef WITH_PROFILE
1178         if (!profile_setup(smbd_messaging_context(), False)) {
1179                 DEBUG(0,("ERROR: failed to setup profiling\n"));
1180                 return -1;
1181         }
1182         if (profile_level != NULL) {
1183                 int pl = atoi(profile_level);
1184                 struct server_id src;
1185
1186                 DEBUG(1, ("setting profiling level: %s\n",profile_level));
1187                 src.pid = getpid();
1188                 set_profile_level(pl, src);
1189         }
1190 #endif
1191
1192         DEBUG(3,( "loaded services\n"));
1193
1194         if (!is_daemon && !is_a_socket(0)) {
1195                 if (!interactive)
1196                         DEBUG(0,("standard input is not a socket, assuming -D option\n"));
1197
1198                 /*
1199                  * Setting is_daemon here prevents us from eventually calling
1200                  * the open_sockets_inetd()
1201                  */
1202
1203                 is_daemon = True;
1204         }
1205
1206         if (is_daemon && !interactive) {
1207                 DEBUG( 3, ( "Becoming a daemon.\n" ) );
1208                 become_daemon(Fork, no_process_group);
1209         }
1210
1211 #if HAVE_SETPGID
1212         /*
1213          * If we're interactive we want to set our own process group for
1214          * signal management.
1215          */
1216         if (interactive && !no_process_group)
1217                 setpgid( (pid_t)0, (pid_t)0);
1218 #endif
1219
1220         if (!directory_exist(lp_lockdir()))
1221                 mkdir(lp_lockdir(), 0755);
1222
1223         if (is_daemon)
1224                 pidfile_create("smbd");
1225
1226         if (!NT_STATUS_IS_OK(reinit_after_fork(smbd_messaging_context(),
1227                              smbd_event_context(), false))) {
1228                 DEBUG(0,("reinit_after_fork() failed\n"));
1229                 exit(1);
1230         }
1231
1232         smbd_setup_sig_term_handler();
1233         smbd_setup_sig_hup_handler();
1234
1235         /* Setup all the TDB's - including CLEAR_IF_FIRST tdb's. */
1236
1237         if (smbd_memcache() == NULL) {
1238                 exit(1);
1239         }
1240
1241         memcache_set_global(smbd_memcache());
1242
1243         /* Initialise the password backed before the global_sam_sid
1244            to ensure that we fetch from ldap before we make a domain sid up */
1245
1246         if(!initialize_password_db(False, smbd_event_context()))
1247                 exit(1);
1248
1249         if (!secrets_init()) {
1250                 DEBUG(0, ("ERROR: smbd can not open secrets.tdb\n"));
1251                 exit(1);
1252         }
1253
1254         if(!get_global_sam_sid()) {
1255                 DEBUG(0,("ERROR: Samba cannot create a SAM SID.\n"));
1256                 exit(1);
1257         }
1258
1259         if (!sessionid_init()) {
1260                 exit(1);
1261         }
1262
1263         if (!connections_init(True))
1264                 exit(1);
1265
1266         if (!locking_init())
1267                 exit(1);
1268
1269         namecache_enable();
1270
1271         if (!W_ERROR_IS_OK(registry_init_full()))
1272                 exit(1);
1273
1274 #if 0
1275         if (!init_svcctl_db())
1276                 exit(1);
1277 #endif
1278
1279         if (!print_backend_init(smbd_messaging_context()))
1280                 exit(1);
1281
1282         if (!init_guest_info()) {
1283                 DEBUG(0,("ERROR: failed to setup guest info.\n"));
1284                 return -1;
1285         }
1286
1287         /* Open the share_info.tdb here, so we don't have to open
1288            after the fork on every single connection.  This is a small
1289            performance improvment and reduces the total number of system
1290            fds used. */
1291         if (!share_info_db_init()) {
1292                 DEBUG(0,("ERROR: failed to load share info db.\n"));
1293                 exit(1);
1294         }
1295
1296         /* only start the background queue daemon if we are 
1297            running as a daemon -- bad things will happen if
1298            smbd is launched via inetd and we fork a copy of 
1299            ourselves here */
1300
1301         if (is_daemon && !interactive
1302             && lp_parm_bool(-1, "smbd", "backgroundqueue", true)) {
1303                 start_background_queue();
1304         }
1305
1306         if (!is_daemon) {
1307                 /* inetd mode */
1308                 TALLOC_FREE(frame);
1309
1310                 /* Started from inetd. fd 0 is the socket. */
1311                 /* We will abort gracefully when the client or remote system
1312                    goes away */
1313                 smbd_set_server_fd(dup(0));
1314
1315                 /* close our standard file descriptors */
1316                 close_low_fds(False); /* Don't close stderr */
1317
1318 #ifdef HAVE_ATEXIT
1319                 atexit(killkids);
1320 #endif
1321
1322                 /* Stop zombies */
1323                 smbd_setup_sig_chld_handler();
1324
1325                 smbd_process();
1326
1327                 exit_server_cleanly(NULL);
1328                 return(0);
1329         }
1330
1331         parent = talloc_zero(smbd_event_context(), struct smbd_parent_context);
1332         if (!parent) {
1333                 exit_server("talloc(struct smbd_parent_context) failed");
1334         }
1335         parent->interactive = interactive;
1336
1337         if (!open_sockets_smbd(parent, ports))
1338                 exit_server("open_sockets_smbd() failed");
1339
1340         TALLOC_FREE(frame);
1341
1342         smbd_parent_loop(parent);
1343
1344         exit_server_cleanly(NULL);
1345         return(0);
1346 }