source4 smdb: Add a post fork hook to the service API
[samba.git] / source4 / wrepl_server / wrepl_server.c
1 /* 
2    Unix SMB/CIFS implementation.
3    
4    WINS Replication server
5    
6    Copyright (C) Stefan Metzmacher      2005
7    
8    This program is free software; you can redistribute it and/or modify
9    it under the terms of the GNU General Public License as published by
10    the Free Software Foundation; either version 3 of the License, or
11    (at your option) any later version.
12    
13    This program is distributed in the hope that it will be useful,
14    but WITHOUT ANY WARRANTY; without even the implied warranty of
15    MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
16    GNU General Public License for more details.
17    
18    You should have received a copy of the GNU General Public License
19    along with this program.  If not, see <http://www.gnu.org/licenses/>.
20 */
21
22 #include "includes.h"
23 #include "../lib/util/dlinklist.h"
24 #include "smbd/service_task.h"
25 #include "smbd/service.h"
26 #include "lib/messaging/irpc.h"
27 #include "librpc/gen_ndr/winsrepl.h"
28 #include "wrepl_server/wrepl_server.h"
29 #include "nbt_server/wins/winsdb.h"
30 #include <ldb.h>
31 #include <ldb_errors.h>
32 #include "auth/auth.h"
33 #include "ldb_wrap.h"
34 #include "param/param.h"
35 #include "lib/socket/netif.h"
36
37 static struct ldb_context *wins_config_db_connect(TALLOC_CTX *mem_ctx, 
38                                                   struct tevent_context *ev_ctx,
39                                                   struct loadparm_context *lp_ctx)
40 {
41         return ldb_wrap_connect(mem_ctx, ev_ctx, lp_ctx, lpcfg_private_path(mem_ctx,
42                                 lp_ctx, "wins_config.ldb"),
43                                 system_session(lp_ctx), NULL, 0);
44 }
45
46 static uint64_t wins_config_db_get_seqnumber(struct ldb_context *ldb)
47 {
48         int ret;
49         struct ldb_dn *dn;
50         struct ldb_result *res = NULL;
51         TALLOC_CTX *tmp_ctx = talloc_new(ldb);
52         uint64_t seqnumber = 0;
53
54         dn = ldb_dn_new(tmp_ctx, ldb, "@BASEINFO");
55         if (!dn) goto failed;
56
57         /* find the record in the WINS database */
58         ret = ldb_search(ldb, tmp_ctx, &res, dn, LDB_SCOPE_BASE, NULL, NULL);
59         if (ret != LDB_SUCCESS) goto failed;
60         if (res->count > 1) goto failed;
61
62         if (res->count == 1) {
63                 seqnumber = ldb_msg_find_attr_as_uint64(res->msgs[0], "sequenceNumber", 0);
64         }
65
66 failed:
67         talloc_free(tmp_ctx);
68         return seqnumber;
69 }
70
71 /*
72   open winsdb
73 */
74 static NTSTATUS wreplsrv_open_winsdb(struct wreplsrv_service *service, 
75                                      struct loadparm_context *lp_ctx)
76 {
77         const char *owner = lpcfg_parm_string(lp_ctx, NULL, "winsdb", "local_owner");
78
79         if (owner == NULL) {
80                 struct interface *ifaces;
81                 load_interface_list(service, lp_ctx, &ifaces);
82                 owner = iface_list_first_v4(ifaces);
83         }
84
85         service->wins_db     = winsdb_connect(service, service->task->event_ctx, lp_ctx, owner, WINSDB_HANDLE_CALLER_WREPL);
86         if (!service->wins_db) {
87                 return NT_STATUS_INTERNAL_DB_ERROR;
88         }
89
90         service->config.ldb = wins_config_db_connect(service, service->task->event_ctx, lp_ctx);
91         if (!service->config.ldb) {
92                 return NT_STATUS_INTERNAL_DB_ERROR;
93         }
94
95         /* the default renew interval is 6 days */
96         service->config.renew_interval    = lpcfg_parm_int(lp_ctx, NULL,"wreplsrv","renew_interval", 6*24*60*60);
97
98         /* the default tombstone (extinction) interval is 6 days */
99         service->config.tombstone_interval= lpcfg_parm_int(lp_ctx, NULL,"wreplsrv","tombstone_interval", 6*24*60*60);
100
101         /* the default tombstone (extinction) timeout is 1 day */
102         service->config.tombstone_timeout = lpcfg_parm_int(lp_ctx, NULL,"wreplsrv","tombstone_timeout", 1*24*60*60);
103
104         /* the default tombstone extra timeout is 3 days */
105         service->config.tombstone_extra_timeout = lpcfg_parm_int(lp_ctx, NULL,"wreplsrv","tombstone_extra_timeout", 3*24*60*60);
106
107         /* the default verify interval is 24 days */
108         service->config.verify_interval   = lpcfg_parm_int(lp_ctx, NULL,"wreplsrv","verify_interval", 24*24*60*60);
109
110         /* the default scavenging interval is 'renew_interval/2' */
111         service->config.scavenging_interval=lpcfg_parm_int(lp_ctx, NULL,"wreplsrv","scavenging_interval",
112                                                         service->config.renew_interval/2);
113
114         /* the maximun interval to the next periodic processing event */
115         service->config.periodic_interval = lpcfg_parm_int(lp_ctx, NULL,"wreplsrv","periodic_interval", 15);
116
117         return NT_STATUS_OK;
118 }
119
120 struct wreplsrv_partner *wreplsrv_find_partner(struct wreplsrv_service *service, const char *peer_addr)
121 {
122         struct wreplsrv_partner *cur;
123
124         for (cur = service->partners; cur; cur = cur->next) {
125                 if (strcmp(cur->address, peer_addr) == 0) {
126                         return cur;
127                 }
128         }
129
130         return NULL;
131 }
132
133 /*
134   load our replication partners
135 */
136 NTSTATUS wreplsrv_load_partners(struct wreplsrv_service *service)
137 {
138         struct wreplsrv_partner *partner;
139         struct ldb_result *res = NULL;
140         int ret;
141         TALLOC_CTX *tmp_ctx;
142         unsigned int i;
143         uint64_t new_seqnumber;
144
145         new_seqnumber = wins_config_db_get_seqnumber(service->config.ldb);
146
147         /* if it's not the first run and nothing changed we're done */
148         if (service->config.seqnumber != 0 && service->config.seqnumber == new_seqnumber) {
149                 return NT_STATUS_OK;
150         }
151
152         tmp_ctx = talloc_new(service);
153         NT_STATUS_HAVE_NO_MEMORY(tmp_ctx);
154
155         service->config.seqnumber = new_seqnumber;
156
157         /* find the record in the WINS database */
158         ret = ldb_search(service->config.ldb, tmp_ctx, &res,
159                          ldb_dn_new(tmp_ctx, service->config.ldb, "CN=PARTNERS"),
160                          LDB_SCOPE_SUBTREE, NULL, "(objectClass=wreplPartner)");
161         if (ret != LDB_SUCCESS) goto failed;
162
163         /* first disable all existing partners */
164         for (partner=service->partners; partner; partner = partner->next) {
165                 partner->type = WINSREPL_PARTNER_NONE;
166         }
167
168         for (i=0; i < res->count; i++) {
169                 const char *address;
170
171                 address = ldb_msg_find_attr_as_string(res->msgs[i], "address", NULL);
172                 if (!address) {
173                         goto failed;
174                 }
175
176                 partner = wreplsrv_find_partner(service, address);
177                 if (partner) {
178                         if (partner->name != partner->address) {
179                                 talloc_free(discard_const(partner->name));
180                         }
181                         partner->name = NULL;
182                         talloc_free(discard_const(partner->our_address));
183                         partner->our_address = NULL;
184
185                         /* force rescheduling of pulling */
186                         partner->pull.next_run = timeval_zero();
187                 } else {
188                         partner = talloc_zero(service, struct wreplsrv_partner);
189                         if (partner == NULL) goto failed;
190
191                         partner->service = service;
192                         partner->address = address;
193                         talloc_steal(partner, partner->address);
194
195                         DLIST_ADD_END(service->partners, partner);
196                 }
197
198                 partner->name                   = ldb_msg_find_attr_as_string(res->msgs[i], "name", partner->address);
199                 talloc_steal(partner, partner->name);
200                 partner->our_address            = ldb_msg_find_attr_as_string(res->msgs[i], "ourAddress", NULL);
201                 talloc_steal(partner, partner->our_address);
202
203                 partner->type                   = ldb_msg_find_attr_as_uint(res->msgs[i], "type", WINSREPL_PARTNER_BOTH);
204                 partner->pull.interval          = ldb_msg_find_attr_as_uint(res->msgs[i], "pullInterval",
205                                                                     WINSREPL_DEFAULT_PULL_INTERVAL);
206                 partner->pull.retry_interval    = ldb_msg_find_attr_as_uint(res->msgs[i], "pullRetryInterval",
207                                                                     WINSREPL_DEFAULT_PULL_RETRY_INTERVAL);
208                 partner->push.change_count      = ldb_msg_find_attr_as_uint(res->msgs[i], "pushChangeCount",
209                                                                     WINSREPL_DEFAULT_PUSH_CHANGE_COUNT);
210                 partner->push.use_inform        = ldb_msg_find_attr_as_uint(res->msgs[i], "pushUseInform", true);
211
212                 DEBUG(3,("wreplsrv_load_partners: found partner: %s type: 0x%X\n",
213                         partner->address, partner->type));
214         }
215
216         DEBUG(2,("wreplsrv_load_partners: %u partners found: wins_config_db seqnumber %llu\n",
217                 res->count, (unsigned long long)service->config.seqnumber));
218
219         talloc_free(tmp_ctx);
220         return NT_STATUS_OK;
221 failed:
222         talloc_free(tmp_ctx);
223         return NT_STATUS_FOOBAR;
224 }
225
226 NTSTATUS wreplsrv_fill_wrepl_table(struct wreplsrv_service *service,
227                                    TALLOC_CTX *mem_ctx,
228                                    struct wrepl_table *table_out,
229                                    const char *initiator,
230                                    bool full_table)
231 {
232         struct wreplsrv_owner *cur;
233         uint32_t i = 0;
234
235         table_out->partner_count        = 0;
236         table_out->partners             = NULL;
237         table_out->initiator            = initiator;
238
239         for (cur = service->table; cur; cur = cur->next) {
240                 if (full_table) {
241                         table_out->partner_count++;
242                         continue;
243                 }
244
245                 if (strcmp(initiator, cur->owner.address) != 0) continue;
246
247                 table_out->partner_count++;
248                 break;
249         }
250
251         table_out->partners = talloc_array(mem_ctx, struct wrepl_wins_owner, table_out->partner_count);
252         NT_STATUS_HAVE_NO_MEMORY(table_out->partners);
253
254         for (cur = service->table; cur && i < table_out->partner_count; cur = cur->next) {
255                 /*
256                  * if it's our local entry
257                  * update the max version
258                  */
259                 if (cur == service->owner) {
260                         cur->owner.max_version = winsdb_get_maxVersion(service->wins_db);
261                 }
262
263                 if (full_table) {
264                         table_out->partners[i] = cur->owner;
265                         i++;
266                         continue;
267                 }
268
269                 if (strcmp(initiator, cur->owner.address) != 0) continue;
270
271                 table_out->partners[i] = cur->owner;
272                 i++;
273                 break;
274         }
275
276         return NT_STATUS_OK;
277 }
278
279 struct wreplsrv_owner *wreplsrv_find_owner(struct wreplsrv_service *service,
280                                            struct wreplsrv_owner *table,
281                                            const char *wins_owner)
282 {
283         struct wreplsrv_owner *cur;
284
285         for (cur = table; cur; cur = cur->next) {
286                 if (strcmp(cur->owner.address, wins_owner) == 0) {
287                         /*
288                          * if it's our local entry
289                          * update the max version
290                          */
291                         if (cur == service->owner) {
292                                 cur->owner.max_version = winsdb_get_maxVersion(service->wins_db);
293                         }
294                         return cur;
295                 }
296         }
297
298         return NULL;
299 }
300
301 /*
302  update the wins_owner_table max_version, if the given version is the highest version
303  if no entry for the wins_owner exists yet, create one
304 */
305 NTSTATUS wreplsrv_add_table(struct wreplsrv_service *service,
306                             TALLOC_CTX *mem_ctx, struct wreplsrv_owner **_table,
307                             const char *wins_owner, uint64_t version)
308 {
309         struct wreplsrv_owner *table = *_table;
310         struct wreplsrv_owner *cur;
311
312         if (!wins_owner || strcmp(wins_owner, "0.0.0.0") == 0) {
313                 wins_owner = service->wins_db->local_owner;
314         }
315
316         cur = wreplsrv_find_owner(service, table, wins_owner);
317
318         /* if it doesn't exists yet, create one */
319         if (!cur) {
320                 cur = talloc_zero(mem_ctx, struct wreplsrv_owner);
321                 NT_STATUS_HAVE_NO_MEMORY(cur);
322
323                 cur->owner.address      = talloc_strdup(cur, wins_owner);
324                 NT_STATUS_HAVE_NO_MEMORY(cur->owner.address);
325                 cur->owner.min_version  = 0;
326                 cur->owner.max_version  = 0;
327                 cur->owner.type         = 1; /* don't know why this is always 1 */
328
329                 cur->partner            = wreplsrv_find_partner(service, wins_owner);
330
331                 DLIST_ADD_END(table, cur);
332                 *_table = table;
333         }
334
335         /* the min_version is always 0 here, and won't be updated */
336
337         /* if the given version is higher than the current max_version, update */
338         if (cur->owner.max_version < version) {
339                 cur->owner.max_version = version;
340                 /* if it's for our local db, we need to update the wins.ldb too */
341                 if (cur == service->owner) {
342                         uint64_t ret;
343                         ret = winsdb_set_maxVersion(service->wins_db, cur->owner.max_version);
344                         if (ret != cur->owner.max_version) {
345                                 DEBUG(0,("winsdb_set_maxVersion(%llu) failed: %llu\n",
346                                          (unsigned long long)cur->owner.max_version, 
347                                          (unsigned long long)ret));
348                                 return NT_STATUS_INTERNAL_DB_CORRUPTION;
349                         }
350                 }
351         }
352
353         return NT_STATUS_OK;
354 }
355
356 /*
357   load the partner table
358 */
359 static NTSTATUS wreplsrv_load_table(struct wreplsrv_service *service)
360 {
361         struct ldb_result *res = NULL;
362         int ret;
363         NTSTATUS status;
364         TALLOC_CTX *tmp_ctx = talloc_new(service);
365         struct ldb_context *ldb = service->wins_db->ldb;
366         unsigned int i;
367         struct wreplsrv_owner *local_owner;
368         const char *wins_owner;
369         uint64_t version;
370         const char * const attrs[] = {
371                 "winsOwner",
372                 "versionID",
373                 NULL
374         };
375
376         /*
377          * make sure we have our local entry in the list,
378          * but we set service->owner when we're done
379          * to avoid to many calls to wreplsrv_local_max_version()
380          */
381         status = wreplsrv_add_table(service,
382                                     service, &service->table,
383                                     service->wins_db->local_owner, 0);
384         if (!NT_STATUS_IS_OK(status)) goto failed;
385         local_owner = wreplsrv_find_owner(service, service->table, service->wins_db->local_owner);
386         if (!local_owner) {
387                 status = NT_STATUS_INTERNAL_ERROR;
388                 goto failed;
389         }
390
391         /* find the record in the WINS database */
392         ret = ldb_search(ldb, tmp_ctx, &res, NULL, LDB_SCOPE_SUBTREE,
393                          attrs, "(objectClass=winsRecord)");
394         status = NT_STATUS_INTERNAL_DB_CORRUPTION;
395         if (ret != LDB_SUCCESS) goto failed;
396
397         for (i=0; i < res->count; i++) {
398                 wins_owner     = ldb_msg_find_attr_as_string(res->msgs[i], "winsOwner", NULL);
399                 version        = ldb_msg_find_attr_as_uint64(res->msgs[i], "versionID", 0);
400
401                 status = wreplsrv_add_table(service,
402                                             service, &service->table,
403                                             wins_owner, version);
404                 if (!NT_STATUS_IS_OK(status)) goto failed;
405                 talloc_free(res->msgs[i]);
406         }
407
408         /*
409          * this makes sure we call wreplsrv_local_max_version() before returning in
410          * wreplsrv_find_owner()
411          */
412         service->owner = local_owner;
413
414         /*
415          * this makes sure the maxVersion in the database is updated,
416          * with the highest version we found, if this is higher than the current stored one
417          */
418         status = wreplsrv_add_table(service,
419                                     service, &service->table,
420                                     service->wins_db->local_owner, local_owner->owner.max_version);
421         if (!NT_STATUS_IS_OK(status)) goto failed;
422
423         talloc_free(tmp_ctx);
424         return NT_STATUS_OK;
425 failed:
426         talloc_free(tmp_ctx);
427         return status;
428 }
429
430 /*
431   setup our replication partners
432 */
433 static NTSTATUS wreplsrv_setup_partners(struct wreplsrv_service *service)
434 {
435         NTSTATUS status;
436
437         status = wreplsrv_load_partners(service);
438         NT_STATUS_NOT_OK_RETURN(status);
439
440         status = wreplsrv_load_table(service);
441         NT_STATUS_NOT_OK_RETURN(status);
442
443         return NT_STATUS_OK;
444 }
445
446 /*
447   startup the wrepl task
448 */
449 static NTSTATUS wreplsrv_task_init(struct task_server *task)
450 {
451         NTSTATUS status;
452         struct wreplsrv_service *service;
453
454         if (!lpcfg_we_are_a_wins_server(task->lp_ctx)) {
455                 return NT_STATUS_INVALID_DOMAIN_ROLE;
456         }
457
458         task_server_set_title(task, "task[wreplsrv]");
459
460         service = talloc_zero(task, struct wreplsrv_service);
461         if (!service) {
462                 task_server_terminate(task, "wreplsrv_task_init: out of memory", true);
463                 return NT_STATUS_NO_MEMORY;
464         }
465         service->task           = task;
466         service->startup_time   = timeval_current();
467         task->private_data      = service;
468
469         /*
470          * setup up all partners, and open the winsdb
471          */
472         status = wreplsrv_open_winsdb(service, task->lp_ctx);
473         if (!NT_STATUS_IS_OK(status)) {
474                 task_server_terminate(task, "wreplsrv_task_init: wreplsrv_open_winsdb() failed", true);
475                 return status;
476         }
477
478         /*
479          * setup timed events for each partner we want to pull from
480          */
481         status = wreplsrv_setup_partners(service);
482         if (!NT_STATUS_IS_OK(status)) {
483                 task_server_terminate(task, "wreplsrv_task_init: wreplsrv_setup_partners() failed", true);
484                 return status;
485         }
486
487         /* 
488          * setup listen sockets, so we can answer requests from our partners,
489          * which pull from us
490          */
491         status = wreplsrv_setup_sockets(service, task->lp_ctx);
492         if (!NT_STATUS_IS_OK(status)) {
493                 task_server_terminate(task, "wreplsrv_task_init: wreplsrv_setup_sockets() failed", true);
494                 return status;
495         }
496
497         status = wreplsrv_setup_periodic(service);
498         if (!NT_STATUS_IS_OK(status)) {
499                 task_server_terminate(task, "wreplsrv_task_init: wreplsrv_setup_periodic() failed", true);
500                 return status;
501         }
502
503         irpc_add_name(task->msg_ctx, "wrepl_server");
504
505         return NT_STATUS_OK;
506 }
507
508 /*
509   register ourselves as a available server
510 */
511 NTSTATUS server_service_wrepl_init(TALLOC_CTX *ctx)
512 {
513         static const struct service_details details = {
514                 .inhibit_fork_on_accept = true,
515                 .inhibit_pre_fork = true,
516                 .task_init = wreplsrv_task_init,
517                 .post_fork = NULL
518         };
519         return register_server_service(ctx, "wrepl", &details);
520 }