r21616: Delay initialization of idmap and nss_info backends until necessary
[samba.git] / source / nsswitch / winbindd_dual.c
1 /* 
2    Unix SMB/CIFS implementation.
3
4    Winbind child daemons
5
6    Copyright (C) Andrew Tridgell 2002
7    Copyright (C) Volker Lendecke 2004,2005
8    
9    This program is free software; you can redistribute it and/or modify
10    it under the terms of the GNU General Public License as published by
11    the Free Software Foundation; either version 2 of the License, or
12    (at your option) any later version.
13    
14    This program is distributed in the hope that it will be useful,
15    but WITHOUT ANY WARRANTY; without even the implied warranty of
16    MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
17    GNU General Public License for more details.
18    
19    You should have received a copy of the GNU General Public License
20    along with this program; if not, write to the Free Software
21    Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA.
22 */
23
24 /*
25  * We fork a child per domain to be able to act non-blocking in the main
26  * winbind daemon. A domain controller thousands of miles away being being
27  * slow replying with a 10.000 user list should not hold up netlogon calls
28  * that can be handled locally.
29  */
30
31 #include "includes.h"
32 #include "winbindd.h"
33
34 #undef DBGC_CLASS
35 #define DBGC_CLASS DBGC_WINBIND
36
37 extern BOOL override_logfile;
38
39 /* Read some data from a client connection */
40
41 static void child_read_request(struct winbindd_cli_state *state)
42 {
43         ssize_t len;
44
45         /* Read data */
46
47         len = read_data(state->sock, (char *)&state->request,
48                         sizeof(state->request));
49
50         if (len != sizeof(state->request)) {
51                 DEBUG(len > 0 ? 0 : 3, ("Got invalid request length: %d\n", (int)len));
52                 state->finished = True;
53                 return;
54         }
55
56         if (state->request.extra_len == 0) {
57                 state->request.extra_data.data = NULL;
58                 return;
59         }
60
61         DEBUG(10, ("Need to read %d extra bytes\n", (int)state->request.extra_len));
62
63         state->request.extra_data.data =
64                 SMB_MALLOC_ARRAY(char, state->request.extra_len + 1);
65
66         if (state->request.extra_data.data == NULL) {
67                 DEBUG(0, ("malloc failed\n"));
68                 state->finished = True;
69                 return;
70         }
71
72         /* Ensure null termination */
73         state->request.extra_data.data[state->request.extra_len] = '\0';
74
75         len = read_data(state->sock, state->request.extra_data.data,
76                         state->request.extra_len);
77
78         if (len != state->request.extra_len) {
79                 DEBUG(0, ("Could not read extra data\n"));
80                 state->finished = True;
81                 return;
82         }
83 }
84
85 /*
86  * Machinery for async requests sent to children. You set up a
87  * winbindd_request, select a child to query, and issue a async_request
88  * call. When the request is completed, the callback function you specified is
89  * called back with the private pointer you gave to async_request.
90  */
91
92 struct winbindd_async_request {
93         struct winbindd_async_request *next, *prev;
94         TALLOC_CTX *mem_ctx;
95         struct winbindd_child *child;
96         struct winbindd_request *request;
97         struct winbindd_response *response;
98         void (*continuation)(void *private_data, BOOL success);
99         void *private_data;
100 };
101
102 static void async_main_request_sent(void *private_data, BOOL success);
103 static void async_request_sent(void *private_data, BOOL success);
104 static void async_reply_recv(void *private_data, BOOL success);
105 static void schedule_async_request(struct winbindd_child *child);
106
107 void async_request(TALLOC_CTX *mem_ctx, struct winbindd_child *child,
108                    struct winbindd_request *request,
109                    struct winbindd_response *response,
110                    void (*continuation)(void *private_data, BOOL success),
111                    void *private_data)
112 {
113         struct winbindd_async_request *state;
114
115         SMB_ASSERT(continuation != NULL);
116
117         state = TALLOC_P(mem_ctx, struct winbindd_async_request);
118
119         if (state == NULL) {
120                 DEBUG(0, ("talloc failed\n"));
121                 continuation(private_data, False);
122                 return;
123         }
124
125         state->mem_ctx = mem_ctx;
126         state->child = child;
127         state->request = request;
128         state->response = response;
129         state->continuation = continuation;
130         state->private_data = private_data;
131
132         DLIST_ADD_END(child->requests, state, struct winbindd_async_request *);
133
134         schedule_async_request(child);
135
136         return;
137 }
138
139 static void async_main_request_sent(void *private_data, BOOL success)
140 {
141         struct winbindd_async_request *state =
142                 talloc_get_type_abort(private_data, struct winbindd_async_request);
143
144         if (!success) {
145                 DEBUG(5, ("Could not send async request\n"));
146
147                 state->response->length = sizeof(struct winbindd_response);
148                 state->response->result = WINBINDD_ERROR;
149                 state->continuation(state->private_data, False);
150                 return;
151         }
152
153         if (state->request->extra_len == 0) {
154                 async_request_sent(private_data, True);
155                 return;
156         }
157
158         setup_async_write(&state->child->event, state->request->extra_data.data,
159                           state->request->extra_len,
160                           async_request_sent, state);
161 }
162
163 static void async_request_sent(void *private_data_data, BOOL success)
164 {
165         struct winbindd_async_request *state =
166                 talloc_get_type_abort(private_data_data, struct winbindd_async_request);
167
168         if (!success) {
169                 DEBUG(5, ("Could not send async request\n"));
170
171                 state->response->length = sizeof(struct winbindd_response);
172                 state->response->result = WINBINDD_ERROR;
173                 state->continuation(state->private_data, False);
174                 return;
175         }
176
177         /* Request successfully sent to the child, setup the wait for reply */
178
179         setup_async_read(&state->child->event,
180                          &state->response->result,
181                          sizeof(state->response->result),
182                          async_reply_recv, state);
183 }
184
185 static void async_reply_recv(void *private_data, BOOL success)
186 {
187         struct winbindd_async_request *state =
188                 talloc_get_type_abort(private_data, struct winbindd_async_request);
189         struct winbindd_child *child = state->child;
190
191         state->response->length = sizeof(struct winbindd_response);
192
193         if (!success) {
194                 DEBUG(5, ("Could not receive async reply\n"));
195
196                 cache_cleanup_response(child->pid);
197                 DLIST_REMOVE(child->requests, state);
198
199                 state->response->result = WINBINDD_ERROR;
200                 state->continuation(state->private_data, False);
201                 return;
202         }
203
204         SMB_ASSERT(cache_retrieve_response(child->pid,
205                                            state->response));
206
207         cache_cleanup_response(child->pid);
208         
209         DLIST_REMOVE(child->requests, state);
210
211         schedule_async_request(child);
212
213         state->continuation(state->private_data, True);
214 }
215
216 static BOOL fork_domain_child(struct winbindd_child *child);
217
218 static void schedule_async_request(struct winbindd_child *child)
219 {
220         struct winbindd_async_request *request = child->requests;
221
222         if (request == NULL) {
223                 return;
224         }
225
226         if (child->event.flags != 0) {
227                 return;         /* Busy */
228         }
229
230         if ((child->pid == 0) && (!fork_domain_child(child))) {
231                 /* Cancel all outstanding requests */
232
233                 while (request != NULL) {
234                         /* request might be free'd in the continuation */
235                         struct winbindd_async_request *next = request->next;
236                         request->continuation(request->private_data, False);
237                         request = next;
238                 }
239                 return;
240         }
241
242         setup_async_write(&child->event, request->request,
243                           sizeof(*request->request),
244                           async_main_request_sent, request);
245
246         return;
247 }
248
249 struct domain_request_state {
250         TALLOC_CTX *mem_ctx;
251         struct winbindd_domain *domain;
252         struct winbindd_request *request;
253         struct winbindd_response *response;
254         void (*continuation)(void *private_data_data, BOOL success);
255         void *private_data_data;
256 };
257
258 static void domain_init_recv(void *private_data_data, BOOL success);
259
260 void async_domain_request(TALLOC_CTX *mem_ctx,
261                           struct winbindd_domain *domain,
262                           struct winbindd_request *request,
263                           struct winbindd_response *response,
264                           void (*continuation)(void *private_data_data, BOOL success),
265                           void *private_data_data)
266 {
267         struct domain_request_state *state;
268
269         if (domain->initialized) {
270                 async_request(mem_ctx, &domain->child, request, response,
271                               continuation, private_data_data);
272                 return;
273         }
274
275         state = TALLOC_P(mem_ctx, struct domain_request_state);
276         if (state == NULL) {
277                 DEBUG(0, ("talloc failed\n"));
278                 continuation(private_data_data, False);
279                 return;
280         }
281
282         state->mem_ctx = mem_ctx;
283         state->domain = domain;
284         state->request = request;
285         state->response = response;
286         state->continuation = continuation;
287         state->private_data_data = private_data_data;
288
289         init_child_connection(domain, domain_init_recv, state);
290 }
291
292 static void recvfrom_child(void *private_data_data, BOOL success)
293 {
294         struct winbindd_cli_state *state =
295                 talloc_get_type_abort(private_data_data, struct winbindd_cli_state);
296         enum winbindd_result result = state->response.result;
297
298         /* This is an optimization: The child has written directly to the
299          * response buffer. The request itself is still in pending state,
300          * state that in the result code. */
301
302         state->response.result = WINBINDD_PENDING;
303
304         if ((!success) || (result != WINBINDD_OK)) {
305                 request_error(state);
306                 return;
307         }
308
309         request_ok(state);
310 }
311
312 void sendto_child(struct winbindd_cli_state *state,
313                   struct winbindd_child *child)
314 {
315         async_request(state->mem_ctx, child, &state->request,
316                       &state->response, recvfrom_child, state);
317 }
318
319 void sendto_domain(struct winbindd_cli_state *state,
320                    struct winbindd_domain *domain)
321 {
322         async_domain_request(state->mem_ctx, domain,
323                              &state->request, &state->response,
324                              recvfrom_child, state);
325 }
326
327 static void domain_init_recv(void *private_data_data, BOOL success)
328 {
329         struct domain_request_state *state =
330                 talloc_get_type_abort(private_data_data, struct domain_request_state);
331
332         if (!success) {
333                 DEBUG(5, ("Domain init returned an error\n"));
334                 state->continuation(state->private_data_data, False);
335                 return;
336         }
337
338         async_request(state->mem_ctx, &state->domain->child,
339                       state->request, state->response,
340                       state->continuation, state->private_data_data);
341 }
342
343 struct winbindd_child_dispatch_table {
344         enum winbindd_cmd cmd;
345         enum winbindd_result (*fn)(struct winbindd_domain *domain,
346                                    struct winbindd_cli_state *state);
347         const char *winbindd_cmd_name;
348 };
349
350 static struct winbindd_child_dispatch_table child_dispatch_table[] = {
351         
352         { WINBINDD_LOOKUPSID,            winbindd_dual_lookupsid,             "LOOKUPSID" },
353         { WINBINDD_LOOKUPNAME,           winbindd_dual_lookupname,            "LOOKUPNAME" },
354         { WINBINDD_LOOKUPRIDS,           winbindd_dual_lookuprids,            "LOOKUPRIDS" },
355         { WINBINDD_LIST_TRUSTDOM,        winbindd_dual_list_trusted_domains,  "LIST_TRUSTDOM" },
356         { WINBINDD_INIT_CONNECTION,      winbindd_dual_init_connection,       "INIT_CONNECTION" },
357         { WINBINDD_GETDCNAME,            winbindd_dual_getdcname,             "GETDCNAME" },
358         { WINBINDD_SHOW_SEQUENCE,        winbindd_dual_show_sequence,         "SHOW_SEQUENCE" },
359         { WINBINDD_PAM_AUTH,             winbindd_dual_pam_auth,              "PAM_AUTH" },
360         { WINBINDD_PAM_AUTH_CRAP,        winbindd_dual_pam_auth_crap,         "AUTH_CRAP" },
361         { WINBINDD_PAM_LOGOFF,           winbindd_dual_pam_logoff,            "PAM_LOGOFF" },
362         { WINBINDD_PAM_CHNG_PSWD_AUTH_CRAP,winbindd_dual_pam_chng_pswd_auth_crap,"CHNG_PSWD_AUTH_CRAP" },
363         { WINBINDD_PAM_CHAUTHTOK,        winbindd_dual_pam_chauthtok,         "PAM_CHAUTHTOK" },
364         { WINBINDD_CHECK_MACHACC,        winbindd_dual_check_machine_acct,    "CHECK_MACHACC" },
365         { WINBINDD_DUAL_SID2UID,         winbindd_dual_sid2uid,               "DUAL_SID2UID" },
366         { WINBINDD_DUAL_SID2GID,         winbindd_dual_sid2gid,               "DUAL_SID2GID" },
367         { WINBINDD_DUAL_SIDS2XIDS,       winbindd_dual_sids2xids,             "DUAL_SIDS2XIDS" },
368         { WINBINDD_DUAL_UID2SID,         winbindd_dual_uid2sid,               "DUAL_UID2SID" },
369         { WINBINDD_DUAL_GID2SID,         winbindd_dual_gid2sid,               "DUAL_GID2SID" },
370         { WINBINDD_DUAL_UID2NAME,        winbindd_dual_uid2name,              "DUAL_UID2NAME" },
371         { WINBINDD_DUAL_NAME2UID,        winbindd_dual_name2uid,              "DUAL_NAME2UID" },
372         { WINBINDD_DUAL_GID2NAME,        winbindd_dual_gid2name,              "DUAL_GID2NAME" },
373         { WINBINDD_DUAL_NAME2GID,        winbindd_dual_name2gid,              "DUAL_NAME2GID" },
374         { WINBINDD_DUAL_SET_MAPPING,     winbindd_dual_set_mapping,           "DUAL_SET_MAPPING" },
375         { WINBINDD_DUAL_SET_HWM,         winbindd_dual_set_hwm,               "DUAL_SET_HWMS" },
376         { WINBINDD_DUAL_DUMP_MAPS,       winbindd_dual_dump_maps,             "DUAL_DUMP_MAPS" },
377         { WINBINDD_DUAL_USERINFO,        winbindd_dual_userinfo,              "DUAL_USERINFO" },
378         { WINBINDD_ALLOCATE_UID,         winbindd_dual_allocate_uid,          "ALLOCATE_UID" },
379         { WINBINDD_ALLOCATE_GID,         winbindd_dual_allocate_gid,          "ALLOCATE_GID" },
380         { WINBINDD_GETUSERDOMGROUPS,     winbindd_dual_getuserdomgroups,      "GETUSERDOMGROUPS" },
381         { WINBINDD_DUAL_GETSIDALIASES,   winbindd_dual_getsidaliases,         "GETSIDALIASES" },
382         { WINBINDD_CCACHE_NTLMAUTH,      winbindd_dual_ccache_ntlm_auth,      "CCACHE_NTLM_AUTH" },
383         /* End of list */
384
385         { WINBINDD_NUM_CMDS, NULL, "NONE" }
386 };
387
388 static void child_process_request(struct winbindd_domain *domain,
389                                   struct winbindd_cli_state *state)
390 {
391         struct winbindd_child_dispatch_table *table;
392
393         /* Free response data - we may be interrupted and receive another
394            command before being able to send this data off. */
395
396         state->response.result = WINBINDD_ERROR;
397         state->response.length = sizeof(struct winbindd_response);
398
399         state->mem_ctx = talloc_init("winbind request");
400         if (state->mem_ctx == NULL)
401                 return;
402
403         /* Process command */
404
405         for (table = child_dispatch_table; table->fn; table++) {
406                 if (state->request.cmd == table->cmd) {
407                         DEBUG(10,("process_request: request fn %s\n",
408                                   table->winbindd_cmd_name ));
409                         state->response.result = table->fn(domain, state);
410                         break;
411                 }
412         }
413
414         if (!table->fn) {
415                 DEBUG(10,("process_request: unknown request fn number %d\n",
416                           (int)state->request.cmd ));
417                 state->response.result = WINBINDD_ERROR;
418         }
419
420         talloc_destroy(state->mem_ctx);
421 }
422
423 void setup_domain_child(struct winbindd_domain *domain,
424                         struct winbindd_child *child,
425                         const char *explicit_logfile)
426 {
427         if (explicit_logfile != NULL) {
428                 pstr_sprintf(child->logfilename, "%s/log.winbindd-%s",
429                              dyn_LOGFILEBASE, explicit_logfile);
430         } else if (domain != NULL) {
431                 pstr_sprintf(child->logfilename, "%s/log.wb-%s",
432                              dyn_LOGFILEBASE, domain->name);
433         } else {
434                 smb_panic("Internal error: domain == NULL && "
435                           "explicit_logfile == NULL");
436         }
437
438         child->domain = domain;
439 }
440
441 struct winbindd_child *children = NULL;
442
443 void winbind_child_died(pid_t pid)
444 {
445         struct winbindd_child *child;
446
447         for (child = children; child != NULL; child = child->next) {
448                 if (child->pid == pid) {
449                         break;
450                 }
451         }
452
453         if (child == NULL) {
454                 DEBUG(0, ("Unknown child %d died!\n", pid));
455                 return;
456         }
457
458         remove_fd_event(&child->event);
459         close(child->event.fd);
460         child->event.fd = 0;
461         child->event.flags = 0;
462         child->pid = 0;
463
464         schedule_async_request(child);
465 }
466
467 /* Ensure any negative cache entries with the netbios or realm names are removed. */
468
469 void winbindd_flush_negative_conn_cache(struct winbindd_domain *domain)
470 {
471         flush_negative_conn_cache_for_domain(domain->name);
472         if (*domain->alt_name) {
473                 flush_negative_conn_cache_for_domain(domain->alt_name);
474         }
475 }
476
477 /* Set our domains as offline and forward the offline message to our children. */
478
479 void winbind_msg_offline(int msg_type, struct process_id src,
480                          void *buf, size_t len, void *private_data)
481 {
482         struct winbindd_child *child;
483         struct winbindd_domain *domain;
484
485         DEBUG(10,("winbind_msg_offline: got offline message.\n"));
486
487         if (!lp_winbind_offline_logon()) {
488                 DEBUG(10,("winbind_msg_offline: rejecting offline message.\n"));
489                 return;
490         }
491
492         /* Set our global state as offline. */
493         if (!set_global_winbindd_state_offline()) {
494                 DEBUG(10,("winbind_msg_offline: offline request failed.\n"));
495                 return;
496         }
497
498         /* Set all our domains as offline. */
499         for (domain = domain_list(); domain; domain = domain->next) {
500                 if (domain->internal) {
501                         continue;
502                 }
503                 DEBUG(5,("winbind_msg_offline: marking %s offline.\n", domain->name));
504                 set_domain_offline(domain);
505
506                 /* Send an offline message to the idmap child when our
507                    primary domain goes offline */
508
509                 if ( domain->primary ) {
510                         struct winbindd_child *idmap = idmap_child();
511
512                         if ( idmap->pid != 0 ) {
513                                 message_send_pid(pid_to_procid(idmap->pid), 
514                                                  MSG_WINBIND_OFFLINE, 
515                                                  domain->name, 
516                                                  strlen(domain->name)+1, 
517                                                  False);
518                         }                       
519                 }
520         }
521
522         for (child = children; child != NULL; child = child->next) {
523                 /* Don't send message to idmap child.  We've already
524                    done so above. */
525                 if (!child->domain || (child == idmap_child())) {
526                         continue;
527                 }
528
529                 /* Or internal domains (this should not be possible....) */
530                 if (child->domain->internal) {
531                         continue;
532                 }
533
534                 /* Each winbindd child should only process requests for one domain - make sure
535                    we only set it online / offline for that domain. */
536
537                 DEBUG(10,("winbind_msg_offline: sending message to pid %u for domain %s.\n",
538                         (unsigned int)child->pid, domain->name ));
539
540                 message_send_pid(pid_to_procid(child->pid), MSG_WINBIND_OFFLINE, child->domain->name,
541                         strlen(child->domain->name)+1, False);
542         }
543 }
544
545 /* Set our domains as online and forward the online message to our children. */
546
547 void winbind_msg_online(int msg_type, struct process_id src,
548                         void *buf, size_t len, void *private_data)
549 {
550         struct winbindd_child *child;
551         struct winbindd_domain *domain;
552
553         DEBUG(10,("winbind_msg_online: got online message.\n"));
554
555         if (!lp_winbind_offline_logon()) {
556                 DEBUG(10,("winbind_msg_online: rejecting online message.\n"));
557                 return;
558         }
559
560         /* Set our global state as online. */
561         set_global_winbindd_state_online();
562
563         smb_nscd_flush_user_cache();
564         smb_nscd_flush_group_cache();
565
566         /* Set all our domains as online. */
567         for (domain = domain_list(); domain; domain = domain->next) {
568                 if (domain->internal) {
569                         continue;
570                 }
571                 DEBUG(5,("winbind_msg_online: requesting %s to go online.\n", domain->name));
572
573                 winbindd_flush_negative_conn_cache(domain);
574                 set_domain_online_request(domain);
575
576                 /* Send an offline message to the idmap child when our
577                    primary domain goes offline */
578
579                 if ( domain->primary ) {
580                         struct winbindd_child *idmap = idmap_child();
581                         
582                         if ( idmap->pid != 0 ) {
583                                 message_send_pid(pid_to_procid(idmap->pid), 
584                                                  MSG_WINBIND_ONLINE,
585                                                  domain->name,
586                                                  strlen(domain->name)+1, 
587                                                  False);
588                         }
589                         
590                 }
591         }
592
593         for (child = children; child != NULL; child = child->next) {
594                 /* Don't send message to idmap child. */
595                 if (!child->domain || (child == idmap_child())) {
596                         continue;
597                 }
598
599                 /* Or internal domains (this should not be possible....) */
600                 if (child->domain->internal) {
601                         continue;
602                 }
603
604                 /* Each winbindd child should only process requests for one domain - make sure
605                    we only set it online / offline for that domain. */
606
607                 DEBUG(10,("winbind_msg_online: sending message to pid %u for domain %s.\n",
608                         (unsigned int)child->pid, child->domain->name ));
609
610                 message_send_pid(pid_to_procid(child->pid), MSG_WINBIND_ONLINE, child->domain->name,
611                         strlen(child->domain->name)+1, False);
612         }
613 }
614
615 /* Forward the online/offline messages to our children. */
616 void winbind_msg_onlinestatus(int msg_type, struct process_id src,
617                               void *buf, size_t len, void *private_data)
618 {
619         struct winbindd_child *child;
620
621         DEBUG(10,("winbind_msg_onlinestatus: got onlinestatus message.\n"));
622
623         for (child = children; child != NULL; child = child->next) {
624                 if (child->domain && child->domain->primary) {
625                         DEBUG(10,("winbind_msg_onlinestatus: "
626                                   "sending message to pid %u of primary domain.\n",
627                                   (unsigned int)child->pid));
628                         message_send_pid(pid_to_procid(child->pid), 
629                                          MSG_WINBIND_ONLINESTATUS, buf, len, False);
630                         break;
631                 }
632         }
633 }
634
635
636 static void account_lockout_policy_handler(struct event_context *ctx,
637                                            struct timed_event *te,
638                                            const struct timeval *now,
639                                            void *private_data)
640 {
641         struct winbindd_child *child =
642                 (struct winbindd_child *)private_data;
643         TALLOC_CTX *mem_ctx = NULL;
644         struct winbindd_methods *methods;
645         SAM_UNK_INFO_12 lockout_policy;
646         NTSTATUS result;
647
648         DEBUG(10,("account_lockout_policy_handler called\n"));
649
650         if (child->lockout_policy_event) {
651                 TALLOC_FREE(child->lockout_policy_event);
652         }
653
654         methods = child->domain->methods;
655
656         mem_ctx = talloc_init("account_lockout_policy_handler ctx");
657         if (!mem_ctx) {
658                 result = NT_STATUS_NO_MEMORY;
659         } else {
660                 result = methods->lockout_policy(child->domain, mem_ctx, &lockout_policy);
661         }
662
663         talloc_destroy(mem_ctx);
664
665         if (!NT_STATUS_IS_OK(result)) {
666                 DEBUG(10,("account_lockout_policy_handler: lockout_policy failed error %s\n",
667                          nt_errstr(result)));
668         }
669
670         child->lockout_policy_event = event_add_timed(winbind_event_context(), NULL,
671                                                       timeval_current_ofs(3600, 0),
672                                                       "account_lockout_policy_handler",
673                                                       account_lockout_policy_handler,
674                                                       child);
675 }
676
677 /* Deal with a request to go offline. */
678
679 static void child_msg_offline(int msg_type, struct process_id src,
680                               void *buf, size_t len, void *private_data)
681 {
682         struct winbindd_domain *domain;
683         const char *domainname = (const char *)buf;
684
685         if (buf == NULL || len == 0) {
686                 return;
687         }
688
689         DEBUG(5,("child_msg_offline received for domain %s.\n", domainname));
690
691         if (!lp_winbind_offline_logon()) {
692                 DEBUG(10,("child_msg_offline: rejecting offline message.\n"));
693                 return;
694         }
695
696         /* Set our global state as offline. */
697         if (!set_global_winbindd_state_offline()) {
698                 DEBUG(10,("child_msg_offline: offline request failed.\n"));
699                 return;
700         }
701
702         /* Mark the requested domain offline. */
703
704         for (domain = domain_list(); domain; domain = domain->next) {
705                 if (domain->internal) {
706                         continue;
707                 }
708                 if (strequal(domain->name, domainname)) {
709                         DEBUG(5,("child_msg_offline: marking %s offline.\n", domain->name));
710                         set_domain_offline(domain);
711                 }
712         }
713 }
714
715 /* Deal with a request to go online. */
716
717 static void child_msg_online(int msg_type, struct process_id src,
718                              void *buf, size_t len, void *private_data)
719 {
720         struct winbindd_domain *domain;
721         const char *domainname = (const char *)buf;
722
723         if (buf == NULL || len == 0) {
724                 return;
725         }
726
727         DEBUG(5,("child_msg_online received for domain %s.\n", domainname));
728
729         if (!lp_winbind_offline_logon()) {
730                 DEBUG(10,("child_msg_online: rejecting online message.\n"));
731                 return;
732         }
733
734         /* Set our global state as online. */
735         set_global_winbindd_state_online();
736
737         /* Try and mark everything online - delete any negative cache entries
738            to force a reconnect now. */
739
740         for (domain = domain_list(); domain; domain = domain->next) {
741                 if (domain->internal) {
742                         continue;
743                 }
744                 if (strequal(domain->name, domainname)) {
745                         DEBUG(5,("child_msg_online: requesting %s to go online.\n", domain->name));
746                         winbindd_flush_negative_conn_cache(domain);
747                         set_domain_online_request(domain);
748                 }
749         }
750 }
751
752 static const char *collect_onlinestatus(TALLOC_CTX *mem_ctx)
753 {
754         struct winbindd_domain *domain;
755         char *buf = NULL;
756
757         if ((buf = talloc_asprintf(mem_ctx, "global:%s ", 
758                                    get_global_winbindd_state_offline() ? 
759                                    "Offline":"Online")) == NULL) {
760                 return NULL;
761         }
762
763         for (domain = domain_list(); domain; domain = domain->next) {
764                 if ((buf = talloc_asprintf_append(buf, "%s:%s ", 
765                                                   domain->name, 
766                                                   domain->online ?
767                                                   "Online":"Offline")) == NULL) {
768                         return NULL;
769                 }
770         }
771
772         buf = talloc_asprintf_append(buf, "\n");
773
774         DEBUG(5,("collect_onlinestatus: %s", buf));
775
776         return buf;
777 }
778
779 static void child_msg_onlinestatus(int msg_type, struct process_id src,
780                                    void *buf, size_t len, void *private_data)
781 {
782         TALLOC_CTX *mem_ctx;
783         const char *message;
784         struct process_id *sender;
785         
786         DEBUG(5,("winbind_msg_onlinestatus received.\n"));
787
788         if (!buf) {
789                 return;
790         }
791
792         sender = (struct process_id *)buf;
793
794         mem_ctx = talloc_init("winbind_msg_onlinestatus");
795         if (mem_ctx == NULL) {
796                 return;
797         }
798         
799         message = collect_onlinestatus(mem_ctx);
800         if (message == NULL) {
801                 talloc_destroy(mem_ctx);
802                 return;
803         }
804
805         message_send_pid(*sender, MSG_WINBIND_ONLINESTATUS, 
806                          message, strlen(message) + 1, True);
807
808         talloc_destroy(mem_ctx);
809 }
810
811 static BOOL fork_domain_child(struct winbindd_child *child)
812 {
813         int fdpair[2];
814         struct winbindd_cli_state state;
815         struct winbindd_domain *domain;
816
817         if (socketpair(AF_UNIX, SOCK_STREAM, 0, fdpair) != 0) {
818                 DEBUG(0, ("Could not open child pipe: %s\n",
819                           strerror(errno)));
820                 return False;
821         }
822
823         ZERO_STRUCT(state);
824         state.pid = sys_getpid();
825
826         /* Stop zombies */
827         CatchChild();
828
829         /* Ensure we don't process messages whilst we're
830            changing the disposition for the child. */
831         message_block();
832
833         child->pid = sys_fork();
834
835         if (child->pid == -1) {
836                 DEBUG(0, ("Could not fork: %s\n", strerror(errno)));
837                 message_unblock();
838                 return False;
839         }
840
841         if (child->pid != 0) {
842                 /* Parent */
843                 close(fdpair[0]);
844                 child->next = child->prev = NULL;
845                 DLIST_ADD(children, child);
846                 child->event.fd = fdpair[1];
847                 child->event.flags = 0;
848                 child->requests = NULL;
849                 add_fd_event(&child->event);
850                 /* We're ok with online/offline messages now. */
851                 message_unblock();
852                 return True;
853         }
854
855         /* Child */
856
857         state.sock = fdpair[0];
858         close(fdpair[1]);
859
860         /* tdb needs special fork handling */
861         if (tdb_reopen_all(1) == -1) {
862                 DEBUG(0,("tdb_reopen_all failed.\n"));
863                 _exit(0);
864         }
865
866         close_conns_after_fork();
867
868         if (!override_logfile) {
869                 lp_set_logfile(child->logfilename);
870                 reopen_logs();
871         }
872
873         /* Don't handle the same messages as our parent. */
874         message_deregister(MSG_SMB_CONF_UPDATED);
875         message_deregister(MSG_SHUTDOWN);
876         message_deregister(MSG_WINBIND_OFFLINE);
877         message_deregister(MSG_WINBIND_ONLINE);
878         message_deregister(MSG_WINBIND_ONLINESTATUS);
879
880         /* The child is ok with online/offline messages now. */
881         message_unblock();
882
883         /* Handle online/offline messages. */
884         message_register(MSG_WINBIND_OFFLINE, child_msg_offline, NULL);
885         message_register(MSG_WINBIND_ONLINE, child_msg_online, NULL);
886         message_register(MSG_WINBIND_ONLINESTATUS, child_msg_onlinestatus,
887                          NULL);
888
889         if ( child->domain ) {
890                 child->domain->startup = True;
891                 child->domain->startup_time = time(NULL);
892         }
893
894         /* Ensure we have no pending check_online events other
895            than one for this domain. */
896
897         for (domain = domain_list(); domain; domain = domain->next) {
898                 if (domain != child->domain) {
899                         if (domain->check_online_event) {
900                                 TALLOC_FREE(domain->check_online_event);
901                         }
902                 }
903         }
904
905         /* Ensure we're not handling an event inherited from
906            our parent. */
907
908         cancel_named_event(winbind_event_context(),
909                            "krb5_ticket_refresh_handler");
910
911         /* We might be in the idmap child...*/
912         if (child->domain && !(child->domain->internal) &&
913             lp_winbind_offline_logon()) {
914
915                 set_domain_online_request(child->domain);
916
917                 child->lockout_policy_event = event_add_timed(
918                         winbind_event_context(), NULL, timeval_zero(),
919                         "account_lockout_policy_handler",
920                         account_lockout_policy_handler,
921                         child);
922         }
923
924         while (1) {
925
926                 int ret;
927                 fd_set read_fds;
928                 struct timeval t;
929                 struct timeval *tp;
930                 struct timeval now;
931
932                 /* free up any talloc memory */
933                 lp_TALLOC_FREE();
934                 main_loop_TALLOC_FREE();
935
936                 run_events(winbind_event_context(), 0, NULL, NULL);
937
938                 GetTimeOfDay(&now);
939
940                 if (child->domain && child->domain->startup &&
941                                 (now.tv_sec > child->domain->startup_time + 30)) {
942                         /* No longer in "startup" mode. */
943                         DEBUG(10,("fork_domain_child: domain %s no longer in 'startup' mode.\n",
944                                 child->domain->name ));
945                         child->domain->startup = False;
946                 }
947
948                 tp = get_timed_events_timeout(winbind_event_context(), &t);
949                 if (tp) {
950                         DEBUG(11,("select will use timeout of %u.%u seconds\n",
951                                 (unsigned int)tp->tv_sec, (unsigned int)tp->tv_usec ));
952                 }
953
954                 /* Handle messages */
955
956                 message_dispatch();
957
958                 FD_ZERO(&read_fds);
959                 FD_SET(state.sock, &read_fds);
960
961                 ret = sys_select(state.sock + 1, &read_fds, NULL, NULL, tp);
962
963                 if (ret == 0) {
964                         DEBUG(11,("nothing is ready yet, continue\n"));
965                         continue;
966                 }
967
968                 if (ret == -1 && errno == EINTR) {
969                         /* We got a signal - continue. */
970                         continue;
971                 }
972
973                 if (ret == -1 && errno != EINTR) {
974                         DEBUG(0,("select error occured\n"));
975                         perror("select");
976                         return False;
977                 }
978
979                 /* fetch a request from the main daemon */
980                 child_read_request(&state);
981
982                 if (state.finished) {
983                         /* we lost contact with our parent */
984                         exit(0);
985                 }
986
987                 DEBUG(4,("child daemon request %d\n", (int)state.request.cmd));
988
989                 ZERO_STRUCT(state.response);
990                 state.request.null_term = '\0';
991                 child_process_request(child->domain, &state);
992
993                 SAFE_FREE(state.request.extra_data.data);
994
995                 cache_store_response(sys_getpid(), &state.response);
996
997                 SAFE_FREE(state.response.extra_data.data);
998
999                 /* We just send the result code back, the result
1000                  * structure needs to be fetched via the
1001                  * winbindd_cache. Hmm. That needs fixing... */
1002
1003                 if (write_data(state.sock,
1004                                (const char *)&state.response.result,
1005                                sizeof(state.response.result)) !=
1006                     sizeof(state.response.result)) {
1007                         DEBUG(0, ("Could not write result\n"));
1008                         exit(1);
1009                 }
1010         }
1011 }