Fix bug #7067 - Linux asynchronous IO (aio) can cause smbd to fail to respond to...
[samba.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                                               server_id_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 static void remove_child_pid(pid_t pid, bool unclean_shutdown)
223 {
224         struct child_pid *child;
225
226         if (unclean_shutdown) {
227                 /* a child terminated uncleanly so tickle all processes to see 
228                    if they can grab any of the pending locks
229                 */
230                 DEBUG(3,(__location__ " Unclean shutdown of pid %u\n", (unsigned int)pid));
231                 messaging_send_buf(smbd_messaging_context(), procid_self(), 
232                                    MSG_SMB_BRL_VALIDATE, NULL, 0);
233                 message_send_all(smbd_messaging_context(), 
234                                  MSG_SMB_UNLOCK, NULL, 0, NULL);
235         }
236
237         for (child = children; child != NULL; child = child->next) {
238                 if (child->pid == pid) {
239                         struct child_pid *tmp = child;
240                         DLIST_REMOVE(children, child);
241                         SAFE_FREE(tmp);
242                         num_children -= 1;
243                         return;
244                 }
245         }
246
247         DEBUG(0, ("Could not find child %d -- ignoring\n", (int)pid));
248 }
249
250 /****************************************************************************
251  Have we reached the process limit ?
252 ****************************************************************************/
253
254 static bool allowable_number_of_smbd_processes(void)
255 {
256         int max_processes = lp_max_smbd_processes();
257
258         if (!max_processes)
259                 return True;
260
261         return num_children < max_processes;
262 }
263
264 static void smbd_sig_chld_handler(struct tevent_context *ev,
265                                   struct tevent_signal *se,
266                                   int signum,
267                                   int count,
268                                   void *siginfo,
269                                   void *private_data)
270 {
271         pid_t pid;
272         int status;
273
274         while ((pid = sys_waitpid(-1, &status, WNOHANG)) > 0) {
275                 bool unclean_shutdown = False;
276
277                 /* If the child terminated normally, assume
278                    it was an unclean shutdown unless the
279                    status is 0
280                 */
281                 if (WIFEXITED(status)) {
282                         unclean_shutdown = WEXITSTATUS(status);
283                 }
284                 /* If the child terminated due to a signal
285                    we always assume it was unclean.
286                 */
287                 if (WIFSIGNALED(status)) {
288                         unclean_shutdown = True;
289                 }
290                 remove_child_pid(pid, unclean_shutdown);
291         }
292 }
293
294 static void smbd_setup_sig_chld_handler(void)
295 {
296         struct tevent_signal *se;
297
298         se = tevent_add_signal(smbd_event_context(),
299                                smbd_event_context(),
300                                SIGCHLD, 0,
301                                smbd_sig_chld_handler,
302                                NULL);
303         if (!se) {
304                 exit_server("failed to setup SIGCHLD handler");
305         }
306 }
307
308 struct smbd_open_socket;
309
310 struct smbd_parent_context {
311         bool interactive;
312
313         /* the list of listening sockets */
314         struct smbd_open_socket *sockets;
315 };
316
317 struct smbd_open_socket {
318         struct smbd_open_socket *prev, *next;
319         struct smbd_parent_context *parent;
320         int fd;
321         struct tevent_fd *fde;
322 };
323
324 static void smbd_open_socket_close_fn(struct tevent_context *ev,
325                                       struct tevent_fd *fde,
326                                       int fd,
327                                       void *private_data)
328 {
329         /* this might be the socket_wrapper swrap_close() */
330         close(fd);
331 }
332
333 static void smbd_accept_connection(struct tevent_context *ev,
334                                    struct tevent_fd *fde,
335                                    uint16_t flags,
336                                    void *private_data)
337 {
338         struct smbd_open_socket *s = talloc_get_type_abort(private_data,
339                                      struct smbd_open_socket);
340         struct sockaddr_storage addr;
341         socklen_t in_addrlen = sizeof(addr);
342         pid_t pid = 0;
343
344         smbd_set_server_fd(accept(s->fd,(struct sockaddr *)&addr,&in_addrlen));
345
346         if (smbd_server_fd() == -1 && errno == EINTR)
347                 return;
348
349         if (smbd_server_fd() == -1) {
350                 DEBUG(0,("open_sockets_smbd: accept: %s\n",
351                          strerror(errno)));
352                 return;
353         }
354
355         if (s->parent->interactive) {
356                 smbd_process();
357                 exit_server_cleanly("end of interactive mode");
358                 return;
359         }
360
361         if (!allowable_number_of_smbd_processes()) {
362                 close(smbd_server_fd());
363                 smbd_set_server_fd(-1);
364                 return;
365         }
366
367         pid = sys_fork();
368         if (pid == 0) {
369                 NTSTATUS status = NT_STATUS_OK;
370                 /* Child code ... */
371                 am_parent = 0;
372
373                 /* Stop zombies, the parent explicitly handles
374                  * them, counting worker smbds. */
375                 CatchChild();
376
377                 /* close our standard file
378                    descriptors */
379                 close_low_fds(False);
380
381                 /*
382                  * Can't use TALLOC_FREE here. Nulling out the argument to it
383                  * would overwrite memory we've just freed.
384                  */
385                 talloc_free(s->parent);
386                 s = NULL;
387
388                 status = reinit_after_fork(smbd_messaging_context(),
389                                            smbd_event_context(), true);
390                 if (!NT_STATUS_IS_OK(status)) {
391                         if (NT_STATUS_EQUAL(status,
392                                             NT_STATUS_TOO_MANY_OPENED_FILES)) {
393                                 DEBUG(0,("child process cannot initialize "
394                                          "because too many files are open\n"));
395                                 goto exit;
396                         }
397                         DEBUG(0,("reinit_after_fork() failed\n"));
398                         smb_panic("reinit_after_fork() failed");
399                 }
400
401                 smbd_setup_sig_term_handler();
402                 smbd_setup_sig_hup_handler();
403
404                 smbd_process();
405          exit:
406                 exit_server_cleanly("end of child");
407                 return;
408         } else if (pid < 0) {
409                 DEBUG(0,("smbd_accept_connection: sys_fork() failed: %s\n",
410                          strerror(errno)));
411         }
412
413         /* The parent doesn't need this socket */
414         close(smbd_server_fd());
415
416         /* Sun May 6 18:56:14 2001 ackley@cs.unm.edu:
417                 Clear the closed fd info out of server_fd --
418                 and more importantly, out of client_fd in
419                 util_sock.c, to avoid a possible
420                 getpeername failure if we reopen the logs
421                 and use %I in the filename.
422         */
423
424         smbd_set_server_fd(-1);
425
426         if (pid != 0) {
427                 add_child_pid(pid);
428         }
429
430         /* Force parent to check log size after
431          * spawning child.  Fix from
432          * klausr@ITAP.Physik.Uni-Stuttgart.De.  The
433          * parent smbd will log to logserver.smb.  It
434          * writes only two messages for each child
435          * started/finished. But each child writes,
436          * say, 50 messages also in logserver.smb,
437          * begining with the debug_count of the
438          * parent, before the child opens its own log
439          * file logserver.client. In a worst case
440          * scenario the size of logserver.smb would be
441          * checked after about 50*50=2500 messages
442          * (ca. 100kb).
443          * */
444         force_check_log_size();
445 }
446
447 static bool smbd_open_one_socket(struct smbd_parent_context *parent,
448                                  const struct sockaddr_storage *ifss,
449                                  uint16_t port)
450 {
451         struct smbd_open_socket *s;
452
453         s = talloc(parent, struct smbd_open_socket);
454         if (!s) {
455                 return false;
456         }
457
458         s->parent = parent;
459         s->fd = open_socket_in(SOCK_STREAM,
460                                port,
461                                parent->sockets == NULL ? 0 : 2,
462                                ifss,
463                                true);
464         if (s->fd == -1) {
465                 DEBUG(0,("smbd_open_once_socket: open_socket_in: "
466                         "%s\n", strerror(errno)));
467                 TALLOC_FREE(s);
468                 /*
469                  * We ignore an error here, as we've done before
470                  */
471                 return true;
472         }
473
474         /* ready to listen */
475         set_socket_options(s->fd, "SO_KEEPALIVE");
476         set_socket_options(s->fd, lp_socket_options());
477
478         /* Set server socket to
479          * non-blocking for the accept. */
480         set_blocking(s->fd, False);
481
482         if (listen(s->fd, SMBD_LISTEN_BACKLOG) == -1) {
483                 DEBUG(0,("open_sockets_smbd: listen: "
484                         "%s\n", strerror(errno)));
485                         close(s->fd);
486                 TALLOC_FREE(s);
487                 return false;
488         }
489
490         s->fde = tevent_add_fd(smbd_event_context(),
491                                s,
492                                s->fd, TEVENT_FD_READ,
493                                smbd_accept_connection,
494                                s);
495         if (!s->fde) {
496                 DEBUG(0,("open_sockets_smbd: "
497                          "tevent_add_fd: %s\n",
498                          strerror(errno)));
499                 close(s->fd);
500                 TALLOC_FREE(s);
501                 return false;
502         }
503         tevent_fd_set_close_fn(s->fde, smbd_open_socket_close_fn);
504
505         DLIST_ADD_END(parent->sockets, s, struct smbd_open_socket *);
506
507         return true;
508 }
509
510 /****************************************************************************
511  Open the socket communication.
512 ****************************************************************************/
513
514 static bool open_sockets_smbd(struct smbd_parent_context *parent,
515                               const char *smb_ports)
516 {
517         int num_interfaces = iface_count();
518         int i;
519         char *ports;
520         unsigned dns_port = 0;
521
522 #ifdef HAVE_ATEXIT
523         atexit(killkids);
524 #endif
525
526         /* Stop zombies */
527         smbd_setup_sig_chld_handler();
528
529         /* use a reasonable default set of ports - listing on 445 and 139 */
530         if (!smb_ports) {
531                 ports = lp_smb_ports();
532                 if (!ports || !*ports) {
533                         ports = talloc_strdup(talloc_tos(), SMB_PORTS);
534                 } else {
535                         ports = talloc_strdup(talloc_tos(), ports);
536                 }
537         } else {
538                 ports = talloc_strdup(talloc_tos(), smb_ports);
539         }
540
541         if (lp_interfaces() && lp_bind_interfaces_only()) {
542                 /* We have been given an interfaces line, and been
543                    told to only bind to those interfaces. Create a
544                    socket per interface and bind to only these.
545                 */
546
547                 /* Now open a listen socket for each of the
548                    interfaces. */
549                 for(i = 0; i < num_interfaces; i++) {
550                         const struct sockaddr_storage *ifss =
551                                         iface_n_sockaddr_storage(i);
552                         char *tok;
553                         const char *ptr;
554
555                         if (ifss == NULL) {
556                                 DEBUG(0,("open_sockets_smbd: "
557                                         "interface %d has NULL IP address !\n",
558                                         i));
559                                 continue;
560                         }
561
562                         for (ptr=ports;
563                              next_token_talloc(talloc_tos(),&ptr, &tok, " \t,");) {
564                                 unsigned port = atoi(tok);
565                                 if (port == 0 || port > 0xffff) {
566                                         continue;
567                                 }
568
569                                 if (!smbd_open_one_socket(parent, ifss, port)) {
570                                         return false;
571                                 }
572                         }
573                 }
574         } else {
575                 /* Just bind to 0.0.0.0 - accept connections
576                    from anywhere. */
577
578                 char *tok;
579                 const char *ptr;
580                 const char *sock_addr = lp_socket_address();
581                 char *sock_tok;
582                 const char *sock_ptr;
583
584                 if (strequal(sock_addr, "0.0.0.0") ||
585                     strequal(sock_addr, "::")) {
586 #if HAVE_IPV6
587                         sock_addr = "::,0.0.0.0";
588 #else
589                         sock_addr = "0.0.0.0";
590 #endif
591                 }
592
593                 for (sock_ptr=sock_addr;
594                      next_token_talloc(talloc_tos(), &sock_ptr, &sock_tok, " \t,"); ) {
595                         for (ptr=ports; next_token_talloc(talloc_tos(), &ptr, &tok, " \t,"); ) {
596                                 struct sockaddr_storage ss;
597
598                                 unsigned port = atoi(tok);
599                                 if (port == 0 || port > 0xffff) {
600                                         continue;
601                                 }
602
603                                 /* Keep the first port for mDNS service
604                                  * registration.
605                                  */
606                                 if (dns_port == 0) {
607                                         dns_port = port;
608                                 }
609
610                                 /* open an incoming socket */
611                                 if (!interpret_string_addr(&ss, sock_tok,
612                                                 AI_NUMERICHOST|AI_PASSIVE)) {
613                                         continue;
614                                 }
615
616                                 if (!smbd_open_one_socket(parent, &ss, port)) {
617                                         return false;
618                                 }
619                         }
620                 }
621         }
622
623         if (parent->sockets == NULL) {
624                 DEBUG(0,("open_sockets_smbd: No "
625                         "sockets available to bind to.\n"));
626                 return false;
627         }
628
629         /* Setup the main smbd so that we can get messages. Note that
630            do this after starting listening. This is needed as when in
631            clustered mode, ctdb won't allow us to start doing database
632            operations until it has gone thru a full startup, which
633            includes checking to see that smbd is listening. */
634         claim_connection(NULL,"",
635                          FLAG_MSG_GENERAL|FLAG_MSG_SMBD|FLAG_MSG_DBWRAP);
636
637         /* Listen to messages */
638
639         messaging_register(smbd_messaging_context(), NULL,
640                            MSG_SMB_SAM_SYNC, msg_sam_sync);
641         messaging_register(smbd_messaging_context(), NULL,
642                            MSG_SHUTDOWN, msg_exit_server);
643         messaging_register(smbd_messaging_context(), NULL,
644                            MSG_SMB_FILE_RENAME, msg_file_was_renamed);
645         messaging_register(smbd_messaging_context(), NULL,
646                            MSG_SMB_CONF_UPDATED, smb_conf_updated);
647         messaging_register(smbd_messaging_context(), NULL,
648                            MSG_SMB_STAT_CACHE_DELETE, smb_stat_cache_delete);
649         messaging_register(smbd_messaging_context(), NULL,
650                            MSG_DEBUG, smbd_msg_debug);
651         brl_register_msgs(smbd_messaging_context());
652
653 #ifdef CLUSTER_SUPPORT
654         if (lp_clustering()) {
655                 ctdbd_register_reconfigure(messaging_ctdbd_connection());
656         }
657 #endif
658
659 #ifdef DEVELOPER
660         messaging_register(smbd_messaging_context(), NULL,
661                            MSG_SMB_INJECT_FAULT, msg_inject_fault);
662 #endif
663
664         if (dns_port != 0) {
665 #ifdef WITH_DNSSD_SUPPORT
666                 smbd_setup_mdns_registration(smbd_event_context(),
667                                              parent, dns_port);
668 #endif
669 #ifdef WITH_AVAHI_SUPPORT
670                 void *avahi_conn;
671
672                 avahi_conn = avahi_start_register(
673                         smbd_event_context(), smbd_event_context(), dns_port);
674                 if (avahi_conn == NULL) {
675                         DEBUG(10, ("avahi_start_register failed\n"));
676                 }
677 #endif
678         }
679
680         return true;
681 }
682
683 static void smbd_parent_loop(struct smbd_parent_context *parent)
684 {
685         /* now accept incoming connections - forking a new process
686            for each incoming connection */
687         DEBUG(2,("waiting for connections\n"));
688         while (1) {
689                 int ret;
690                 TALLOC_CTX *frame = talloc_stackframe();
691
692                 ret = tevent_loop_once(smbd_event_context());
693                 if (ret != 0) {
694                         exit_server_cleanly("tevent_loop_once() error");
695                 }
696
697                 TALLOC_FREE(frame);
698         } /* end while 1 */
699
700 /* NOTREACHED   return True; */
701 }
702
703 /****************************************************************************
704  Reload printers
705 **************************************************************************/
706 void reload_printers(void)
707 {
708         int snum;
709         int n_services = lp_numservices();
710         int pnum = lp_servicenumber(PRINTERS_NAME);
711         const char *pname;
712
713         pcap_cache_reload();
714
715         /* remove stale printers */
716         for (snum = 0; snum < n_services; snum++) {
717                 /* avoid removing PRINTERS_NAME or non-autoloaded printers */
718                 if (snum == pnum || !(lp_snum_ok(snum) && lp_print_ok(snum) &&
719                                       lp_autoloaded(snum)))
720                         continue;
721
722                 pname = lp_printername(snum);
723                 if (!pcap_printername_ok(pname)) {
724                         DEBUG(3, ("removing stale printer %s\n", pname));
725
726                         if (is_printer_published(NULL, snum, NULL))
727                                 nt_printer_publish(NULL, snum, DSPRINT_UNPUBLISH);
728                         del_a_printer(pname);
729                         lp_killservice(snum);
730                 }
731         }
732
733         load_printers();
734 }
735
736 /****************************************************************************
737  Reload the services file.
738 **************************************************************************/
739
740 bool reload_services(bool test)
741 {
742         bool ret;
743
744         if (lp_loaded()) {
745                 char *fname = lp_configfile();
746                 if (file_exist(fname) &&
747                     !strcsequal(fname, get_dyn_CONFIGFILE())) {
748                         set_dyn_CONFIGFILE(fname);
749                         test = False;
750                 }
751         }
752
753         reopen_logs();
754
755         if (test && !lp_file_list_changed())
756                 return(True);
757
758         lp_killunused(conn_snum_used);
759
760         ret = lp_load(get_dyn_CONFIGFILE(), False, False, True, True);
761
762         reload_printers();
763
764         /* perhaps the config filename is now set */
765         if (!test)
766                 reload_services(True);
767
768         reopen_logs();
769
770         load_interfaces();
771
772         if (smbd_server_fd() != -1) {
773                 set_socket_options(smbd_server_fd(),"SO_KEEPALIVE");
774                 set_socket_options(smbd_server_fd(), lp_socket_options());
775         }
776
777         mangle_reset_cache();
778         reset_stat_cache();
779
780         /* this forces service parameters to be flushed */
781         set_current_service(NULL,0,True);
782
783         return(ret);
784 }
785
786 /****************************************************************************
787  Exit the server.
788 ****************************************************************************/
789
790 /* Reasons for shutting down a server process. */
791 enum server_exit_reason { SERVER_EXIT_NORMAL, SERVER_EXIT_ABNORMAL };
792
793 static void exit_server_common(enum server_exit_reason how,
794         const char *const reason) _NORETURN_;
795
796 static void exit_server_common(enum server_exit_reason how,
797         const char *const reason)
798 {
799         bool had_open_conn = false;
800         struct smbd_server_connection *sconn = smbd_server_conn;
801
802         if (!exit_firsttime)
803                 exit(0);
804         exit_firsttime = false;
805
806         change_to_root_user();
807
808         if (sconn && sconn->smb1.negprot.auth_context) {
809                 struct auth_context *a = sconn->smb1.negprot.auth_context;
810                 a->free(&sconn->smb1.negprot.auth_context);
811         }
812
813         if (sconn) {
814                 had_open_conn = conn_close_all(sconn);
815                 invalidate_all_vuids(sconn);
816         }
817
818         /* 3 second timeout. */
819         print_notify_send_messages(smbd_messaging_context(), 3);
820
821         /* delete our entry in the connections database. */
822         yield_connection(NULL,"");
823
824 #ifdef WITH_DFS
825         if (dcelogin_atmost_once) {
826                 dfs_unlogin();
827         }
828 #endif
829
830 #ifdef USE_DMAPI
831         /* Destroy Samba DMAPI session only if we are master smbd process */
832         if (am_parent) {
833                 if (!dmapi_destroy_session()) {
834                         DEBUG(0,("Unable to close Samba DMAPI session\n"));
835                 }
836         }
837 #endif
838
839         locking_end();
840         printing_end();
841
842         /*
843          * we need to force the order of freeing the following,
844          * because smbd_msg_ctx is not a talloc child of smbd_server_conn.
845          */
846         sconn = NULL;
847         TALLOC_FREE(smbd_server_conn);
848         TALLOC_FREE(smbd_msg_ctx);
849         TALLOC_FREE(smbd_event_ctx);
850
851         if (how != SERVER_EXIT_NORMAL) {
852                 int oldlevel = DEBUGLEVEL;
853
854                 DEBUGLEVEL = 10;
855
856                 DEBUGSEP(0);
857                 DEBUG(0,("Abnormal server exit: %s\n",
858                         reason ? reason : "no explanation provided"));
859                 DEBUGSEP(0);
860
861                 log_stack_trace();
862
863                 DEBUGLEVEL = oldlevel;
864                 dump_core();
865
866         } else {    
867                 DEBUG(3,("Server exit (%s)\n",
868                         (reason ? reason : "normal exit")));
869                 if (am_parent) {
870                         pidfile_unlink();
871                 }
872                 gencache_stabilize();
873         }
874
875         /* if we had any open SMB connections when we exited then we
876            need to tell the parent smbd so that it can trigger a retry
877            of any locks we may have been holding or open files we were
878            blocking */
879         if (had_open_conn) {
880                 exit(1);
881         } else {
882                 exit(0);
883         }
884 }
885
886 void exit_server(const char *const explanation)
887 {
888         exit_server_common(SERVER_EXIT_ABNORMAL, explanation);
889 }
890
891 void exit_server_cleanly(const char *const explanation)
892 {
893         exit_server_common(SERVER_EXIT_NORMAL, explanation);
894 }
895
896 void exit_server_fault(void)
897 {
898         exit_server("critical server fault");
899 }
900
901 /****************************************************************************
902  Initialise connect, service and file structs.
903 ****************************************************************************/
904
905 static bool init_structs(void )
906 {
907         /*
908          * Set the machine NETBIOS name if not already
909          * set from the config file.
910          */
911
912         if (!init_names())
913                 return False;
914
915         file_init();
916
917         if (!secrets_init())
918                 return False;
919
920         return True;
921 }
922
923 /****************************************************************************
924  main program.
925 ****************************************************************************/
926
927 /* Declare prototype for build_options() to avoid having to run it through
928    mkproto.h.  Mixing $(builddir) and $(srcdir) source files in the current
929    prototype generation system is too complicated. */
930
931 extern void build_options(bool screen);
932
933  int main(int argc,const char *argv[])
934 {
935         /* shall I run as a daemon */
936         bool is_daemon = false;
937         bool interactive = false;
938         bool Fork = true;
939         bool no_process_group = false;
940         bool log_stdout = false;
941         char *ports = NULL;
942         char *profile_level = NULL;
943         int opt;
944         poptContext pc;
945         bool print_build_options = False;
946         enum {
947                 OPT_DAEMON = 1000,
948                 OPT_INTERACTIVE,
949                 OPT_FORK,
950                 OPT_NO_PROCESS_GROUP,
951                 OPT_LOG_STDOUT
952         };
953         struct poptOption long_options[] = {
954         POPT_AUTOHELP
955         {"daemon", 'D', POPT_ARG_NONE, NULL, OPT_DAEMON, "Become a daemon (default)" },
956         {"interactive", 'i', POPT_ARG_NONE, NULL, OPT_INTERACTIVE, "Run interactive (not a daemon)"},
957         {"foreground", 'F', POPT_ARG_NONE, NULL, OPT_FORK, "Run daemon in foreground (for daemontools, etc.)" },
958         {"no-process-group", '\0', POPT_ARG_NONE, NULL, OPT_NO_PROCESS_GROUP, "Don't create a new process group" },
959         {"log-stdout", 'S', POPT_ARG_NONE, NULL, OPT_LOG_STDOUT, "Log to stdout" },
960         {"build-options", 'b', POPT_ARG_NONE, NULL, 'b', "Print build options" },
961         {"port", 'p', POPT_ARG_STRING, &ports, 0, "Listen on the specified ports"},
962         {"profiling-level", 'P', POPT_ARG_STRING, &profile_level, 0, "Set profiling level","PROFILE_LEVEL"},
963         POPT_COMMON_SAMBA
964         POPT_COMMON_DYNCONFIG
965         POPT_TABLEEND
966         };
967         struct smbd_parent_context *parent = NULL;
968         TALLOC_CTX *frame = talloc_stackframe(); /* Setup tos. */
969
970         smbd_init_globals();
971
972         TimeInit();
973
974 #ifdef HAVE_SET_AUTH_PARAMETERS
975         set_auth_parameters(argc,argv);
976 #endif
977
978         pc = poptGetContext("smbd", argc, argv, long_options, 0);
979         while((opt = poptGetNextOpt(pc)) != -1) {
980                 switch (opt)  {
981                 case OPT_DAEMON:
982                         is_daemon = true;
983                         break;
984                 case OPT_INTERACTIVE:
985                         interactive = true;
986                         break;
987                 case OPT_FORK:
988                         Fork = false;
989                         break;
990                 case OPT_NO_PROCESS_GROUP:
991                         no_process_group = true;
992                         break;
993                 case OPT_LOG_STDOUT:
994                         log_stdout = true;
995                         break;
996                 case 'b':
997                         print_build_options = True;
998                         break;
999                 default:
1000                         d_fprintf(stderr, "\nInvalid option %s: %s\n\n",
1001                                   poptBadOption(pc, 0), poptStrerror(opt));
1002                         poptPrintUsage(pc, stderr, 0);
1003                         exit(1);
1004                 }
1005         }
1006         poptFreeContext(pc);
1007
1008         if (interactive) {
1009                 Fork = False;
1010                 log_stdout = True;
1011         }
1012
1013         setup_logging(argv[0],log_stdout);
1014
1015         if (print_build_options) {
1016                 build_options(True); /* Display output to screen as well as debug */
1017                 exit(0);
1018         }
1019
1020         load_case_tables();
1021
1022 #ifdef HAVE_SETLUID
1023         /* needed for SecureWare on SCO */
1024         setluid(0);
1025 #endif
1026
1027         sec_init();
1028
1029         set_remote_machine_name("smbd", False);
1030
1031         if (interactive && (DEBUGLEVEL >= 9)) {
1032                 talloc_enable_leak_report();
1033         }
1034
1035         if (log_stdout && Fork) {
1036                 DEBUG(0,("ERROR: Can't log to stdout (-S) unless daemon is in foreground (-F) or interactive (-i)\n"));
1037                 exit(1);
1038         }
1039
1040         /* we want to re-seed early to prevent time delays causing
1041            client problems at a later date. (tridge) */
1042         generate_random_buffer(NULL, 0);
1043
1044         /* make absolutely sure we run as root - to handle cases where people
1045            are crazy enough to have it setuid */
1046
1047         gain_root_privilege();
1048         gain_root_group_privilege();
1049
1050         /*
1051          * Ensure we have CAP_KILL capability set on Linux,
1052          * where we need this to communicate with threads.
1053          * This is inherited by new threads, but not by new
1054          * processes across exec().
1055          */
1056         set_effective_capability(KILL_CAPABILITY);
1057
1058         fault_setup((void (*)(void *))exit_server_fault);
1059         dump_core_setup("smbd");
1060
1061         /* we are never interested in SIGPIPE */
1062         BlockSignals(True,SIGPIPE);
1063
1064 #if defined(SIGFPE)
1065         /* we are never interested in SIGFPE */
1066         BlockSignals(True,SIGFPE);
1067 #endif
1068
1069 #if defined(SIGUSR2)
1070         /* We are no longer interested in USR2 */
1071         BlockSignals(True,SIGUSR2);
1072 #endif
1073
1074         /* POSIX demands that signals are inherited. If the invoking process has
1075          * these signals masked, we will have problems, as we won't recieve them. */
1076         BlockSignals(False, SIGHUP);
1077         BlockSignals(False, SIGUSR1);
1078         BlockSignals(False, SIGTERM);
1079
1080         /* Ensure we leave no zombies until we
1081          * correctly set up child handling below. */
1082
1083         CatchChild();
1084
1085         /* we want total control over the permissions on created files,
1086            so set our umask to 0 */
1087         umask(0);
1088
1089         init_sec_ctx();
1090
1091         reopen_logs();
1092
1093         DEBUG(0,("smbd version %s started.\n", samba_version_string()));
1094         DEBUGADD(0,("%s\n", COPYRIGHT_STARTUP_MESSAGE));
1095
1096         DEBUG(2,("uid=%d gid=%d euid=%d egid=%d\n",
1097                  (int)getuid(),(int)getgid(),(int)geteuid(),(int)getegid()));
1098
1099         /* Output the build options to the debug log */ 
1100         build_options(False);
1101
1102         if (sizeof(uint16) < 2 || sizeof(uint32) < 4) {
1103                 DEBUG(0,("ERROR: Samba is not configured correctly for the word size on your machine\n"));
1104                 exit(1);
1105         }
1106
1107         if (!lp_load_initial_only(get_dyn_CONFIGFILE())) {
1108                 DEBUG(0, ("error opening config file\n"));
1109                 exit(1);
1110         }
1111
1112         if (smbd_messaging_context() == NULL)
1113                 exit(1);
1114
1115         if (!reload_services(False))
1116                 return(-1);     
1117
1118         init_structs();
1119
1120 #ifdef WITH_PROFILE
1121         if (!profile_setup(smbd_messaging_context(), False)) {
1122                 DEBUG(0,("ERROR: failed to setup profiling\n"));
1123                 return -1;
1124         }
1125         if (profile_level != NULL) {
1126                 int pl = atoi(profile_level);
1127                 struct server_id src;
1128
1129                 DEBUG(1, ("setting profiling level: %s\n",profile_level));
1130                 src.pid = getpid();
1131                 set_profile_level(pl, src);
1132         }
1133 #endif
1134
1135         DEBUG(3,( "loaded services\n"));
1136
1137         if (!is_daemon && !is_a_socket(0)) {
1138                 if (!interactive)
1139                         DEBUG(0,("standard input is not a socket, assuming -D option\n"));
1140
1141                 /*
1142                  * Setting is_daemon here prevents us from eventually calling
1143                  * the open_sockets_inetd()
1144                  */
1145
1146                 is_daemon = True;
1147         }
1148
1149         if (is_daemon && !interactive) {
1150                 DEBUG( 3, ( "Becoming a daemon.\n" ) );
1151                 become_daemon(Fork, no_process_group);
1152         }
1153
1154 #if HAVE_SETPGID
1155         /*
1156          * If we're interactive we want to set our own process group for
1157          * signal management.
1158          */
1159         if (interactive && !no_process_group)
1160                 setpgid( (pid_t)0, (pid_t)0);
1161 #endif
1162
1163         if (!directory_exist(lp_lockdir()))
1164                 mkdir(lp_lockdir(), 0755);
1165
1166         if (is_daemon)
1167                 pidfile_create("smbd");
1168
1169         if (!NT_STATUS_IS_OK(reinit_after_fork(smbd_messaging_context(),
1170                              smbd_event_context(), false))) {
1171                 DEBUG(0,("reinit_after_fork() failed\n"));
1172                 exit(1);
1173         }
1174
1175         smbd_setup_sig_term_handler();
1176         smbd_setup_sig_hup_handler();
1177
1178         /* Setup all the TDB's - including CLEAR_IF_FIRST tdb's. */
1179
1180         if (smbd_memcache() == NULL) {
1181                 exit(1);
1182         }
1183
1184         memcache_set_global(smbd_memcache());
1185
1186         /* Initialise the password backed before the global_sam_sid
1187            to ensure that we fetch from ldap before we make a domain sid up */
1188
1189         if(!initialize_password_db(False, smbd_event_context()))
1190                 exit(1);
1191
1192         if (!secrets_init()) {
1193                 DEBUG(0, ("ERROR: smbd can not open secrets.tdb\n"));
1194                 exit(1);
1195         }
1196
1197         if(!get_global_sam_sid()) {
1198                 DEBUG(0,("ERROR: Samba cannot create a SAM SID.\n"));
1199                 exit(1);
1200         }
1201
1202         if (!session_init())
1203                 exit(1);
1204
1205         if (!connections_init(True))
1206                 exit(1);
1207
1208         if (!locking_init())
1209                 exit(1);
1210
1211         namecache_enable();
1212
1213         if (!W_ERROR_IS_OK(registry_init_full()))
1214                 exit(1);
1215
1216 #if 0
1217         if (!init_svcctl_db())
1218                 exit(1);
1219 #endif
1220
1221         if (!print_backend_init(smbd_messaging_context()))
1222                 exit(1);
1223
1224         if (!init_guest_info()) {
1225                 DEBUG(0,("ERROR: failed to setup guest info.\n"));
1226                 return -1;
1227         }
1228
1229         /* Open the share_info.tdb here, so we don't have to open
1230            after the fork on every single connection.  This is a small
1231            performance improvment and reduces the total number of system
1232            fds used. */
1233         if (!share_info_db_init()) {
1234                 DEBUG(0,("ERROR: failed to load share info db.\n"));
1235                 exit(1);
1236         }
1237
1238         /* only start the background queue daemon if we are 
1239            running as a daemon -- bad things will happen if
1240            smbd is launched via inetd and we fork a copy of 
1241            ourselves here */
1242
1243         if (is_daemon && !interactive
1244             && lp_parm_bool(-1, "smbd", "backgroundqueue", true)) {
1245                 start_background_queue();
1246         }
1247
1248         if (!is_daemon) {
1249                 /* inetd mode */
1250                 TALLOC_FREE(frame);
1251
1252                 /* Started from inetd. fd 0 is the socket. */
1253                 /* We will abort gracefully when the client or remote system
1254                    goes away */
1255                 smbd_set_server_fd(dup(0));
1256
1257                 /* close our standard file descriptors */
1258                 close_low_fds(False); /* Don't close stderr */
1259
1260 #ifdef HAVE_ATEXIT
1261                 atexit(killkids);
1262 #endif
1263
1264                 /* Stop zombies */
1265                 smbd_setup_sig_chld_handler();
1266
1267                 smbd_process();
1268
1269                 exit_server_cleanly(NULL);
1270                 return(0);
1271         }
1272
1273         parent = talloc_zero(smbd_event_context(), struct smbd_parent_context);
1274         if (!parent) {
1275                 exit_server("talloc(struct smbd_parent_context) failed");
1276         }
1277         parent->interactive = interactive;
1278
1279         if (!open_sockets_smbd(parent, ports))
1280                 exit_server("open_sockets_smbd() failed");
1281
1282         TALLOC_FREE(frame);
1283
1284         smbd_parent_loop(parent);
1285
1286         exit_server_cleanly(NULL);
1287         return(0);
1288 }