Merge branch 'master' of ssh://jra@git.samba.org/data/git/samba
[kai/samba.git] / source4 / wrepl_server / wrepl_scavenging.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 "librpc/gen_ndr/ndr_winsrepl.h"
24 #include "wrepl_server/wrepl_server.h"
25 #include "nbt_server/wins/winsdb.h"
26 #include "ldb/include/ldb.h"
27 #include "ldb/include/ldb_errors.h"
28 #include "system/time.h"
29 #include "smbd/service_task.h"
30 #include "lib/messaging/irpc.h"
31 #include "librpc/gen_ndr/ndr_irpc.h"
32 #include "librpc/gen_ndr/ndr_nbt.h"
33
34 const char *wreplsrv_owner_filter(struct wreplsrv_service *service,
35                                   TALLOC_CTX *mem_ctx,
36                                   const char *wins_owner)
37 {
38         if (strcmp(wins_owner, service->wins_db->local_owner) == 0) {
39                 return talloc_asprintf(mem_ctx, "(|(winsOwner=%s)(winsOwner=0.0.0.0))",
40                                        wins_owner);
41         }
42
43         return talloc_asprintf(mem_ctx, "(&(winsOwner=%s)(!(winsOwner=0.0.0.0)))",
44                                wins_owner);
45 }
46
47 static NTSTATUS wreplsrv_scavenging_owned_records(struct wreplsrv_service *service, TALLOC_CTX *tmp_mem)
48 {
49         NTSTATUS status;
50         struct winsdb_record *rec = NULL;
51         struct ldb_result *res = NULL;
52         const char *owner_filter;
53         const char *filter;
54         uint32_t i;
55         int ret;
56         time_t now = time(NULL);
57         const char *now_timestr;
58         const char *action;
59         const char *old_state=NULL;
60         const char *new_state=NULL;
61         uint32_t modify_flags;
62         bool modify_record;
63         bool delete_record;
64         bool delete_tombstones;
65         struct timeval tombstone_extra_time;
66
67         now_timestr = ldb_timestring(tmp_mem, now);
68         NT_STATUS_HAVE_NO_MEMORY(now_timestr);
69         owner_filter = wreplsrv_owner_filter(service, tmp_mem,
70                                              service->wins_db->local_owner);
71         NT_STATUS_HAVE_NO_MEMORY(owner_filter);
72         filter = talloc_asprintf(tmp_mem,
73                                  "(&%s(objectClass=winsRecord)"
74                                  "(expireTime<=%s))",
75                                  owner_filter, now_timestr);
76         NT_STATUS_HAVE_NO_MEMORY(filter);
77         ret = ldb_search(service->wins_db->ldb, tmp_mem, &res, NULL, LDB_SCOPE_SUBTREE, NULL, "%s", filter);
78         if (ret != LDB_SUCCESS) return NT_STATUS_INTERNAL_DB_CORRUPTION;
79         DEBUG(10,("WINS scavenging: filter '%s' count %d\n", filter, res->count));
80
81         tombstone_extra_time = timeval_add(&service->startup_time,
82                                            service->config.tombstone_extra_timeout,
83                                            0);
84         delete_tombstones = timeval_expired(&tombstone_extra_time);
85
86         for (i=0; i < res->count; i++) {
87                 /*
88                  * we pass '0' as 'now' here,
89                  * because we want to get the raw timestamps which are in the DB
90                  */
91                 status = winsdb_record(service->wins_db, res->msgs[i], tmp_mem, 0, &rec);
92                 NT_STATUS_NOT_OK_RETURN(status);
93                 talloc_free(res->msgs[i]);
94
95                 modify_flags    = 0;
96                 modify_record   = false;
97                 delete_record   = false;
98
99                 switch (rec->state) {
100                 case WREPL_STATE_ACTIVE:
101                         old_state       = "active";
102                         new_state       = "active";
103                         if (!rec->is_static) {
104                                 new_state       = "released";
105                                 rec->state      = WREPL_STATE_RELEASED;
106                                 rec->expire_time= service->config.tombstone_interval + now;
107                         }
108                         modify_flags    = 0;
109                         modify_record   = true;
110                         break;
111
112                 case WREPL_STATE_RELEASED:
113                         old_state       = "released";
114                         new_state       = "tombstone";
115                         rec->state      = WREPL_STATE_TOMBSTONE;
116                         rec->expire_time= service->config.tombstone_timeout + now;
117                         modify_flags    = WINSDB_FLAG_ALLOC_VERSION | WINSDB_FLAG_TAKE_OWNERSHIP;
118                         modify_record   = true;
119                         break;
120
121                 case WREPL_STATE_TOMBSTONE:
122                         old_state       = "tombstone";
123                         new_state       = "tombstone";
124                         if (!delete_tombstones) break;
125                         new_state       = "deleted";
126                         delete_record = true;
127                         break;
128
129                 case WREPL_STATE_RESERVED:
130                         DEBUG(0,("%s: corrupted record: %s\n",
131                                 __location__, nbt_name_string(rec, rec->name)));
132                         return NT_STATUS_INTERNAL_DB_CORRUPTION;
133                 }
134
135                 if (modify_record) {
136                         action = "modify";
137                         ret = winsdb_modify(service->wins_db, rec, modify_flags);
138                 } else if (delete_record) {
139                         action = "delete";
140                         ret = winsdb_delete(service->wins_db, rec);
141                 } else {
142                         action = "skip";
143                         ret = NBT_RCODE_OK;
144                 }
145
146                 if (ret != NBT_RCODE_OK) {
147                         DEBUG(1,("WINS scavenging: failed to %s name %s (owned:%s -> owned:%s): error:%u\n",
148                                 action, nbt_name_string(rec, rec->name), old_state, new_state, ret));
149                 } else {
150                         DEBUG(4,("WINS scavenging: %s name: %s (owned:%s -> owned:%s)\n",
151                                 action, nbt_name_string(rec, rec->name), old_state, new_state));
152                 }
153
154                 talloc_free(rec);
155         }
156
157         return NT_STATUS_OK;
158 }
159
160 static NTSTATUS wreplsrv_scavenging_replica_non_active_records(struct wreplsrv_service *service, TALLOC_CTX *tmp_mem)
161 {
162         NTSTATUS status;
163         struct winsdb_record *rec = NULL;
164         struct ldb_result *res = NULL;
165         const char *owner_filter;
166         const char *filter;
167         uint32_t i;
168         int ret;
169         time_t now = time(NULL);
170         const char *now_timestr;
171         const char *action;
172         const char *old_state=NULL;
173         const char *new_state=NULL;
174         uint32_t modify_flags;
175         bool modify_record;
176         bool delete_record;
177         bool delete_tombstones;
178         struct timeval tombstone_extra_time;
179
180         now_timestr = ldb_timestring(tmp_mem, now);
181         NT_STATUS_HAVE_NO_MEMORY(now_timestr);
182         owner_filter = wreplsrv_owner_filter(service, tmp_mem,
183                                              service->wins_db->local_owner);
184         NT_STATUS_HAVE_NO_MEMORY(owner_filter);
185         filter = talloc_asprintf(tmp_mem,
186                                  "(&(!%s)(objectClass=winsRecord)"
187                                  "(!(recordState=%u))(expireTime<=%s))",
188                                  owner_filter, WREPL_STATE_ACTIVE, now_timestr);
189         NT_STATUS_HAVE_NO_MEMORY(filter);
190         ret = ldb_search(service->wins_db->ldb, tmp_mem, &res, NULL, LDB_SCOPE_SUBTREE, NULL, "%s", filter);
191         if (ret != LDB_SUCCESS) return NT_STATUS_INTERNAL_DB_CORRUPTION;
192         DEBUG(10,("WINS scavenging: filter '%s' count %d\n", filter, res->count));
193
194         tombstone_extra_time = timeval_add(&service->startup_time,
195                                            service->config.tombstone_extra_timeout,
196                                            0);
197         delete_tombstones = timeval_expired(&tombstone_extra_time);
198
199         for (i=0; i < res->count; i++) {
200                 /*
201                  * we pass '0' as 'now' here,
202                  * because we want to get the raw timestamps which are in the DB
203                  */
204                 status = winsdb_record(service->wins_db, res->msgs[i], tmp_mem, 0, &rec);
205                 NT_STATUS_NOT_OK_RETURN(status);
206                 talloc_free(res->msgs[i]);
207
208                 modify_flags    = 0;
209                 modify_record   = false;
210                 delete_record   = false;
211
212                 switch (rec->state) {
213                 case WREPL_STATE_ACTIVE:
214                         DEBUG(0,("%s: corrupted record: %s\n",
215                                 __location__, nbt_name_string(rec, rec->name)));
216                         return NT_STATUS_INTERNAL_DB_CORRUPTION;
217
218                 case WREPL_STATE_RELEASED:
219                         old_state       = "released";
220                         new_state       = "tombstone";
221                         rec->state      = WREPL_STATE_TOMBSTONE;
222                         rec->expire_time= service->config.tombstone_timeout + now;
223                         modify_flags    = 0;
224                         modify_record   = true;
225                         break;
226
227                 case WREPL_STATE_TOMBSTONE:
228                         old_state       = "tombstone";
229                         new_state       = "tombstone";
230                         if (!delete_tombstones) break;
231                         new_state       = "deleted";
232                         delete_record = true;
233                         break;
234
235                 case WREPL_STATE_RESERVED:
236                         DEBUG(0,("%s: corrupted record: %s\n",
237                                 __location__, nbt_name_string(rec, rec->name)));
238                         return NT_STATUS_INTERNAL_DB_CORRUPTION;
239                 }
240
241                 if (modify_record) {
242                         action = "modify";
243                         ret = winsdb_modify(service->wins_db, rec, modify_flags);
244                 } else if (delete_record) {
245                         action = "delete";
246                         ret = winsdb_delete(service->wins_db, rec);
247                 } else {
248                         action = "skip";
249                         ret = NBT_RCODE_OK;
250                 }
251
252                 if (ret != NBT_RCODE_OK) {
253                         DEBUG(1,("WINS scavenging: failed to %s name %s (replica:%s -> replica:%s): error:%u\n",
254                                 action, nbt_name_string(rec, rec->name), old_state, new_state, ret));
255                 } else {
256                         DEBUG(4,("WINS scavenging: %s name: %s (replica:%s -> replica:%s)\n",
257                                 action, nbt_name_string(rec, rec->name), old_state, new_state));
258                 }
259
260                 talloc_free(rec);
261         }
262
263         return NT_STATUS_OK;
264 }
265
266 struct verify_state {
267         struct messaging_context *msg_ctx;
268         struct wreplsrv_service *service;
269         struct winsdb_record *rec;
270         struct nbtd_proxy_wins_challenge r;
271 };
272
273 static void verify_handler(struct irpc_request *ireq)
274 {
275         struct verify_state *s = talloc_get_type(ireq->async.private,
276                                  struct verify_state);
277         struct winsdb_record *rec = s->rec;
278         const char *action;
279         const char *old_state = "active";
280         const char *new_state = "active";
281         const char *new_owner = "replica";
282         uint32_t modify_flags = 0;
283         bool modify_record = false;
284         bool delete_record = false;
285         bool different = false;
286         int ret;
287         NTSTATUS status;
288         uint32_t i, j;
289
290         /*
291          * - if the name isn't present anymore remove our record
292          * - if the name is found and not a normal group check if the addresses match,
293          *   - if they don't match remove the record
294          *   - if they match do nothing
295          * - if an error happens do nothing
296          */
297         status = irpc_call_recv(ireq);
298         if (NT_STATUS_EQUAL(NT_STATUS_OBJECT_NAME_NOT_FOUND, status)) {
299                 delete_record = true;
300                 new_state = "deleted";
301         } else if (NT_STATUS_IS_OK(status) && rec->type != WREPL_TYPE_GROUP) {
302                 for (i=0; i < s->r.out.num_addrs; i++) {
303                         bool found = false;
304                         for (j=0; rec->addresses[j]; j++) {
305                                 if (strcmp(s->r.out.addrs[i].addr, rec->addresses[j]->address) == 0) {
306                                         found = true;
307                                         break;
308                                 }
309                         }
310                         if (!found) {
311                                 different = true;
312                                 break;
313                         }
314                 }
315         } else if (NT_STATUS_IS_OK(status) && rec->type == WREPL_TYPE_GROUP) {
316                 if (s->r.out.num_addrs != 1 || strcmp(s->r.out.addrs[0].addr, "255.255.255.255") != 0) {
317                         different = true;
318                 }
319         }
320
321         if (different) {
322                 /*
323                  * if the reply from the owning wins server has different addresses
324                  * then take the ownership of the record and make it a tombstone
325                  * this will then hopefully replicated to the original owner of the record
326                  * which will then propagate it's own record, so that the current record will
327                  * be replicated to to us
328                  */
329                 DEBUG(0,("WINS scavenging: replica %s verify got different addresses from winsserver: %s: tombstoning record\n",
330                         nbt_name_string(rec, rec->name), rec->wins_owner));
331
332                 rec->state      = WREPL_STATE_TOMBSTONE;
333                 rec->expire_time= time(NULL) + s->service->config.tombstone_timeout;
334                 for (i=0; rec->addresses[i]; i++) {
335                         rec->addresses[i]->expire_time = rec->expire_time;
336                 }
337                 modify_record   = true;
338                 modify_flags    = WINSDB_FLAG_ALLOC_VERSION | WINSDB_FLAG_TAKE_OWNERSHIP;
339                 new_state       = "tombstone";
340                 new_owner       = "owned";
341         } else if (NT_STATUS_IS_OK(status)) {
342                 /* if the addresses are the same, just update the timestamps */
343                 rec->expire_time = time(NULL) + s->service->config.verify_interval;
344                 for (i=0; rec->addresses[i]; i++) {
345                         rec->addresses[i]->expire_time = rec->expire_time;
346                 }
347                 modify_record   = true;
348                 modify_flags    = 0;
349                 new_state       = "active";
350         }
351
352         if (modify_record) {
353                 action = "modify";
354                 ret = winsdb_modify(s->service->wins_db, rec, modify_flags);
355         } else if (delete_record) {
356                 action = "delete";
357                 ret = winsdb_delete(s->service->wins_db, rec);
358         } else {
359                 action = "skip";
360                 ret = NBT_RCODE_OK;
361         }
362
363         if (ret != NBT_RCODE_OK) {
364                 DEBUG(1,("WINS scavenging: failed to %s name %s (replica:%s -> %s:%s): error:%u\n",
365                         action, nbt_name_string(rec, rec->name), old_state, new_owner, new_state, ret));
366         } else {
367                 DEBUG(4,("WINS scavenging: %s name: %s (replica:%s -> %s:%s): %s: %s\n",
368                         action, nbt_name_string(rec, rec->name), old_state, new_owner, new_state,
369                         rec->wins_owner, nt_errstr(status)));
370         }
371
372         talloc_free(s);
373 }
374
375 static NTSTATUS wreplsrv_scavenging_replica_active_records(struct wreplsrv_service *service, TALLOC_CTX *tmp_mem)
376 {
377         NTSTATUS status;
378         struct winsdb_record *rec = NULL;
379         struct ldb_result *res = NULL;
380         const char *owner_filter;
381         const char *filter;
382         uint32_t i;
383         int ret;
384         time_t now = time(NULL);
385         const char *now_timestr;
386         struct irpc_request *ireq;
387         struct verify_state *s;
388         struct server_id *nbt_servers;
389
390         nbt_servers = irpc_servers_byname(service->task->msg_ctx, tmp_mem, "nbt_server");
391         if ((nbt_servers == NULL) || (nbt_servers[0].id == 0)) {
392                 return NT_STATUS_INTERNAL_ERROR;
393         }
394
395         now_timestr = ldb_timestring(tmp_mem, now);
396         NT_STATUS_HAVE_NO_MEMORY(now_timestr);
397         owner_filter = wreplsrv_owner_filter(service, tmp_mem,
398                                              service->wins_db->local_owner);
399         NT_STATUS_HAVE_NO_MEMORY(owner_filter);
400         filter = talloc_asprintf(tmp_mem,
401                                  "(&(!%s)(objectClass=winsRecord)"
402                                  "(recordState=%u)(expireTime<=%s))",
403                                  owner_filter, WREPL_STATE_ACTIVE, now_timestr);
404         NT_STATUS_HAVE_NO_MEMORY(filter);
405         ret = ldb_search(service->wins_db->ldb, tmp_mem, &res, NULL, LDB_SCOPE_SUBTREE, NULL, "%s", filter);
406         if (ret != LDB_SUCCESS) return NT_STATUS_INTERNAL_DB_CORRUPTION;
407         DEBUG(10,("WINS scavenging: filter '%s' count %d\n", filter, res->count));
408
409         for (i=0; i < res->count; i++) {
410                 /*
411                  * we pass '0' as 'now' here,
412                  * because we want to get the raw timestamps which are in the DB
413                  */
414                 status = winsdb_record(service->wins_db, res->msgs[i], tmp_mem, 0, &rec);
415                 NT_STATUS_NOT_OK_RETURN(status);
416                 talloc_free(res->msgs[i]);
417
418                 if (rec->state != WREPL_STATE_ACTIVE) {
419                         DEBUG(0,("%s: corrupted record: %s\n",
420                                 __location__, nbt_name_string(rec, rec->name)));
421                         return NT_STATUS_INTERNAL_DB_CORRUPTION;
422                 }
423
424                 /* 
425                  * ask the owning wins server if the record still exists,
426                  * if not delete the record
427                  *
428                  * TODO: NOTE: this is a simpliefied version, to verify that
429                  *             a record still exist, I assume that w2k3 uses
430                  *             DCERPC calls or some WINSREPL packets for this,
431                  *             but we use a wins name query
432                  */
433                 DEBUG(0,("ask wins server '%s' if '%s' with version_id:%llu still exists\n",
434                          rec->wins_owner, nbt_name_string(rec, rec->name), 
435                          (unsigned long long)rec->version));
436
437                 s = talloc_zero(tmp_mem, struct verify_state);
438                 NT_STATUS_HAVE_NO_MEMORY(s);
439                 s->msg_ctx      = service->task->msg_ctx;
440                 s->service      = service;
441                 s->rec          = talloc_steal(s, rec);
442
443                 s->r.in.name            = *rec->name;
444                 s->r.in.num_addrs       = 1;
445                 s->r.in.addrs           = talloc_array(s, struct nbtd_proxy_wins_addr, s->r.in.num_addrs);
446                 NT_STATUS_HAVE_NO_MEMORY(s->r.in.addrs);
447                 /* TODO: fix pidl to handle inline ipv4address arrays */
448                 s->r.in.addrs[0].addr   = rec->wins_owner;
449
450                 ireq = IRPC_CALL_SEND(s->msg_ctx, nbt_servers[0],
451                                       irpc, NBTD_PROXY_WINS_CHALLENGE,
452                                       &s->r, s);
453                 NT_STATUS_HAVE_NO_MEMORY(ireq);
454
455                 ireq->async.fn          = verify_handler;
456                 ireq->async.private     = s;
457
458                 talloc_steal(service, s);
459         }
460
461         return NT_STATUS_OK;
462 }
463
464 NTSTATUS wreplsrv_scavenging_run(struct wreplsrv_service *service)
465 {
466         NTSTATUS status;
467         TALLOC_CTX *tmp_mem;
468         bool skip_first_run = false;
469
470         if (!timeval_expired(&service->scavenging.next_run)) {
471                 return NT_STATUS_OK;
472         }
473
474         if (timeval_is_zero(&service->scavenging.next_run)) {
475                 skip_first_run = true;
476         }
477
478         service->scavenging.next_run = timeval_current_ofs(service->config.scavenging_interval, 0);
479         status = wreplsrv_periodic_schedule(service, service->config.scavenging_interval);
480         NT_STATUS_NOT_OK_RETURN(status);
481
482         /*
483          * if it's the first time this functions is called (startup)
484          * the next_run is zero, in this case we should not do scavenging
485          */
486         if (skip_first_run) {
487                 return NT_STATUS_OK;
488         }
489
490         if (service->scavenging.processing) {
491                 return NT_STATUS_OK;
492         }
493
494         DEBUG(4,("wreplsrv_scavenging_run(): start\n"));
495
496         tmp_mem = talloc_new(service);
497         NT_STATUS_HAVE_NO_MEMORY(tmp_mem);
498         service->scavenging.processing = true;
499         status = wreplsrv_scavenging_owned_records(service,tmp_mem);
500         service->scavenging.processing = false;
501         talloc_free(tmp_mem);
502         NT_STATUS_NOT_OK_RETURN(status);
503
504         tmp_mem = talloc_new(service);  
505         NT_STATUS_HAVE_NO_MEMORY(tmp_mem);
506         service->scavenging.processing = true;
507         status = wreplsrv_scavenging_replica_non_active_records(service, tmp_mem);
508         service->scavenging.processing = false;
509         talloc_free(tmp_mem);
510         NT_STATUS_NOT_OK_RETURN(status);
511
512         tmp_mem = talloc_new(service);
513         NT_STATUS_HAVE_NO_MEMORY(tmp_mem);
514         service->scavenging.processing = true;
515         status = wreplsrv_scavenging_replica_active_records(service, tmp_mem);
516         service->scavenging.processing = false;
517         talloc_free(tmp_mem);
518         NT_STATUS_NOT_OK_RETURN(status);
519
520         DEBUG(4,("wreplsrv_scavenging_run(): end\n"));
521
522         return NT_STATUS_OK;
523 }