s4:samba_dnsupdate: cache the already registered records
[Samba.git] / source4 / dsdb / dns / dns_update.c
blobaa617c6aeca3ca0301c4314fb0c677ca911fb68d
1 /*
2 Unix SMB/CIFS mplementation.
4 DNS update service
6 Copyright (C) Andrew Tridgell 2009
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.
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.
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/>.
24 this module auto-creates the named.conf.update file, which tells
25 bind9 what KRB5 principals it should accept for updates to our zone
27 It also uses the samba_dnsupdate script to auto-create the right DNS
28 names for ourselves as a DC in the domain, using TSIG-GSS
31 #include "includes.h"
32 #include "dsdb/samdb/samdb.h"
33 #include "auth/auth.h"
34 #include "smbd/service.h"
35 #include "lib/messaging/irpc.h"
36 #include "param/param.h"
37 #include "system/filesys.h"
38 #include "dsdb/common/util.h"
39 #include "libcli/composite/composite.h"
40 #include "libcli/security/dom_sid.h"
41 #include "librpc/gen_ndr/ndr_irpc.h"
43 NTSTATUS server_service_dnsupdate_init(void);
45 struct dnsupdate_service {
46 struct task_server *task;
47 struct auth_session_info *system_session_info;
48 struct ldb_context *samdb;
50 /* status for periodic config file update */
51 struct {
52 uint32_t interval;
53 struct tevent_timer *te;
54 struct tevent_req *subreq;
55 NTSTATUS status;
56 } confupdate;
58 /* status for periodic DNS name check */
59 struct {
60 uint32_t interval;
61 struct tevent_timer *te;
62 struct tevent_req *subreq;
63 struct tevent_req *spnreq;
64 NTSTATUS status;
65 } nameupdate;
69 called when rndc reload has finished
71 static void dnsupdate_rndc_done(struct tevent_req *subreq)
73 struct dnsupdate_service *service = tevent_req_callback_data(subreq,
74 struct dnsupdate_service);
75 int ret;
76 int sys_errno;
78 service->confupdate.subreq = NULL;
80 ret = samba_runcmd_recv(subreq, &sys_errno);
81 TALLOC_FREE(subreq);
82 if (ret != 0) {
83 service->confupdate.status = map_nt_error_from_unix_common(sys_errno);
84 } else {
85 service->confupdate.status = NT_STATUS_OK;
88 if (!NT_STATUS_IS_OK(service->confupdate.status)) {
89 DEBUG(0,(__location__ ": Failed rndc update - %s\n",
90 nt_errstr(service->confupdate.status)));
91 } else {
92 DEBUG(3,("Completed rndc reload OK\n"));
97 called every 'dnsupdate:conf interval' seconds
99 static void dnsupdate_rebuild(struct dnsupdate_service *service)
101 int ret;
102 size_t size;
103 struct ldb_result *res1, *res2;
104 const char *tmp_path, *path, *path_static;
105 char *static_policies;
106 int fd;
107 unsigned int i;
108 const char *attrs1[] = { "msDS-HasDomainNCs", NULL };
109 const char *attrs2[] = { "name", NULL };
110 const char *realm = lpcfg_realm(service->task->lp_ctx);
111 TALLOC_CTX *tmp_ctx = talloc_new(service);
112 const char * const *rndc_command = lpcfg_rndc_command(service->task->lp_ctx);
113 const char **dc_list;
114 int dc_count=0;
116 /* abort any pending script run */
117 TALLOC_FREE(service->confupdate.subreq);
119 /* find the DNs for all the non-RODC DCs in the forest */
120 ret = dsdb_search(service->samdb, tmp_ctx, &res1, ldb_get_config_basedn(service->samdb),
121 LDB_SCOPE_SUBTREE,
122 attrs1,
124 "(&(objectclass=NTDSDSA)(!(msDS-isRODC=TRUE)))");
125 if (ret != LDB_SUCCESS) {
126 DEBUG(0,(__location__ ": Unable to find DCs list - %s", ldb_errstring(service->samdb)));
127 talloc_free(tmp_ctx);
128 return;
131 dc_list = talloc_array(tmp_ctx, const char *, 0);
132 for (i=0; i<res1->count; i++) {
133 struct ldb_dn *server_dn = res1->msgs[i]->dn;
134 struct ldb_dn *domain_dn;
135 const char *acct_name, *full_account, *dns_domain;
137 /* this is a nasty hack to form the account name of
138 * this DC. We do it this way as we don't necessarily
139 * have access to the domain NC, so all we have to go
140 * on is what is in the configuration partition
143 domain_dn = ldb_msg_find_attr_as_dn(service->samdb, tmp_ctx, res1->msgs[i], "msDS-HasDomainNCs");
144 if (domain_dn == NULL) continue;
146 ldb_dn_remove_child_components(server_dn, 1);
147 ret = dsdb_search_dn(service->samdb, tmp_ctx, &res2, server_dn, attrs2, 0);
148 if (ret != LDB_SUCCESS) {
149 continue;
152 acct_name = ldb_msg_find_attr_as_string(res2->msgs[0], "name", NULL);
153 if (acct_name == NULL) continue;
155 dns_domain = samdb_dn_to_dns_domain(tmp_ctx, domain_dn);
156 if (dns_domain == NULL) {
157 continue;
160 full_account = talloc_asprintf(tmp_ctx, "%s$@%s", acct_name, dns_domain);
161 if (full_account == NULL) continue;
163 dc_list = talloc_realloc(tmp_ctx, dc_list, const char *, dc_count+1);
164 if (dc_list == NULL) {
165 continue;
167 dc_list[dc_count++] = full_account;
170 path = lpcfg_parm_string(service->task->lp_ctx, NULL, "dnsupdate", "path");
171 if (path == NULL) {
172 path = lpcfg_private_path(tmp_ctx, service->task->lp_ctx, "named.conf.update");
175 path_static = lpcfg_parm_string(service->task->lp_ctx, NULL, "dnsupdate", "extra_static_grant_rules");
176 if (path_static == NULL) {
177 path_static = lpcfg_private_path(tmp_ctx, service->task->lp_ctx, "named.conf.update.static");
180 tmp_path = talloc_asprintf(tmp_ctx, "%s.tmp", path);
181 if (path == NULL || tmp_path == NULL || path_static == NULL ) {
182 DEBUG(0,(__location__ ": Unable to get paths\n"));
183 talloc_free(tmp_ctx);
184 return;
187 static_policies = file_load(path_static, &size, 0, tmp_ctx);
189 unlink(tmp_path);
190 fd = open(tmp_path, O_CREAT|O_TRUNC|O_WRONLY, 0444);
191 if (fd == -1) {
192 DEBUG(1,(__location__ ": Unable to open %s - %s\n", tmp_path, strerror(errno)));
193 talloc_free(tmp_ctx);
194 return;
197 dprintf(fd, "/* this file is auto-generated - do not edit */\n");
198 dprintf(fd, "update-policy {\n");
199 if( static_policies != NULL ) {
200 dprintf(fd, "/* Start of static entries */\n");
201 dprintf(fd, "%s\n",static_policies);
202 dprintf(fd, "/* End of static entries */\n");
204 dprintf(fd, "\tgrant %s ms-self * A AAAA;\n", realm);
205 dprintf(fd, "\tgrant Administrator@%s wildcard * A AAAA SRV CNAME;\n", realm);
207 for (i=0; i<dc_count; i++) {
208 dprintf(fd, "\tgrant %s wildcard * A AAAA SRV CNAME;\n", dc_list[i]);
210 dprintf(fd, "};\n");
211 close(fd);
214 if (NT_STATUS_IS_OK(service->confupdate.status) &&
215 file_compare(tmp_path, path) == true) {
216 unlink(tmp_path);
217 talloc_free(tmp_ctx);
218 return;
221 if (rename(tmp_path, path) != 0) {
222 DEBUG(0,(__location__ ": Failed to rename %s to %s - %s\n",
223 tmp_path, path, strerror(errno)));
224 talloc_free(tmp_ctx);
225 return;
228 DEBUG(2,("Loading new DNS update grant rules\n"));
229 service->confupdate.subreq = samba_runcmd_send(service,
230 service->task->event_ctx,
231 timeval_current_ofs(10, 0),
232 2, 0,
233 rndc_command,
234 "reload", NULL);
235 if (service->confupdate.subreq == NULL) {
236 DEBUG(0,(__location__ ": samba_runcmd_send() failed with no memory\n"));
237 talloc_free(tmp_ctx);
238 return;
240 tevent_req_set_callback(service->confupdate.subreq,
241 dnsupdate_rndc_done,
242 service);
244 talloc_free(tmp_ctx);
247 static NTSTATUS dnsupdate_confupdate_schedule(struct dnsupdate_service *service);
250 called every 'dnsupdate:conf interval' seconds
252 static void dnsupdate_confupdate_handler_te(struct tevent_context *ev, struct tevent_timer *te,
253 struct timeval t, void *ptr)
255 struct dnsupdate_service *service = talloc_get_type(ptr, struct dnsupdate_service);
257 dnsupdate_rebuild(service);
258 dnsupdate_confupdate_schedule(service);
262 static NTSTATUS dnsupdate_confupdate_schedule(struct dnsupdate_service *service)
264 service->confupdate.te = tevent_add_timer(service->task->event_ctx, service,
265 timeval_current_ofs(service->confupdate.interval, 0),
266 dnsupdate_confupdate_handler_te, service);
267 NT_STATUS_HAVE_NO_MEMORY(service->confupdate.te);
268 return NT_STATUS_OK;
273 called when dns update script has finished
275 static void dnsupdate_nameupdate_done(struct tevent_req *subreq)
277 struct dnsupdate_service *service = tevent_req_callback_data(subreq,
278 struct dnsupdate_service);
279 int ret;
280 int sys_errno;
282 service->nameupdate.subreq = NULL;
284 ret = samba_runcmd_recv(subreq, &sys_errno);
285 TALLOC_FREE(subreq);
286 if (ret != 0) {
287 service->nameupdate.status = map_nt_error_from_unix_common(sys_errno);
288 } else {
289 service->nameupdate.status = NT_STATUS_OK;
292 if (!NT_STATUS_IS_OK(service->nameupdate.status)) {
293 DEBUG(0,(__location__ ": Failed DNS update - %s\n",
294 nt_errstr(service->nameupdate.status)));
295 } else {
296 DEBUG(3,("Completed DNS update check OK\n"));
302 called when spn update script has finished
304 static void dnsupdate_spnupdate_done(struct tevent_req *subreq)
306 struct dnsupdate_service *service = tevent_req_callback_data(subreq,
307 struct dnsupdate_service);
308 int ret;
309 int sys_errno;
311 service->nameupdate.spnreq = NULL;
313 ret = samba_runcmd_recv(subreq, &sys_errno);
314 TALLOC_FREE(subreq);
315 if (ret != 0) {
316 service->nameupdate.status = map_nt_error_from_unix_common(sys_errno);
317 } else {
318 service->nameupdate.status = NT_STATUS_OK;
321 if (!NT_STATUS_IS_OK(service->nameupdate.status)) {
322 DEBUG(0,(__location__ ": Failed SPN update - %s\n",
323 nt_errstr(service->nameupdate.status)));
324 } else {
325 DEBUG(3,("Completed SPN update check OK\n"));
330 called every 'dnsupdate:name interval' seconds
332 static void dnsupdate_check_names(struct dnsupdate_service *service)
334 const char * const *dns_update_command = lpcfg_dns_update_command(service->task->lp_ctx);
335 const char * const *spn_update_command = lpcfg_spn_update_command(service->task->lp_ctx);
337 /* kill any existing child */
338 TALLOC_FREE(service->nameupdate.subreq);
340 DEBUG(3,("Calling DNS name update script\n"));
341 service->nameupdate.subreq = samba_runcmd_send(service,
342 service->task->event_ctx,
343 timeval_current_ofs(20, 0),
344 2, 0,
345 dns_update_command,
346 NULL);
347 if (service->nameupdate.subreq == NULL) {
348 DEBUG(0,(__location__ ": samba_runcmd_send() failed with no memory\n"));
349 return;
351 tevent_req_set_callback(service->nameupdate.subreq,
352 dnsupdate_nameupdate_done,
353 service);
355 DEBUG(3,("Calling SPN name update script\n"));
356 service->nameupdate.spnreq = samba_runcmd_send(service,
357 service->task->event_ctx,
358 timeval_current_ofs(20, 0),
359 2, 0,
360 spn_update_command,
361 NULL);
362 if (service->nameupdate.spnreq == NULL) {
363 DEBUG(0,(__location__ ": samba_runcmd_send() failed with no memory\n"));
364 return;
366 tevent_req_set_callback(service->nameupdate.spnreq,
367 dnsupdate_spnupdate_done,
368 service);
371 static NTSTATUS dnsupdate_nameupdate_schedule(struct dnsupdate_service *service);
374 called every 'dnsupdate:name interval' seconds
376 static void dnsupdate_nameupdate_handler_te(struct tevent_context *ev, struct tevent_timer *te,
377 struct timeval t, void *ptr)
379 struct dnsupdate_service *service = talloc_get_type(ptr, struct dnsupdate_service);
381 dnsupdate_check_names(service);
382 dnsupdate_nameupdate_schedule(service);
386 static NTSTATUS dnsupdate_nameupdate_schedule(struct dnsupdate_service *service)
388 service->nameupdate.te = tevent_add_timer(service->task->event_ctx, service,
389 timeval_current_ofs(service->nameupdate.interval, 0),
390 dnsupdate_nameupdate_handler_te, service);
391 NT_STATUS_HAVE_NO_MEMORY(service->nameupdate.te);
392 return NT_STATUS_OK;
396 struct dnsupdate_RODC_state {
397 struct irpc_message *msg;
398 struct dnsupdate_RODC *r;
399 char *tmp_path;
400 char *tmp_path2;
401 int fd;
404 static int dnsupdate_RODC_destructor(struct dnsupdate_RODC_state *st)
406 if (st->fd != -1) {
407 close(st->fd);
409 unlink(st->tmp_path);
410 if (st->tmp_path2 != NULL) {
411 unlink(st->tmp_path2);
413 return 0;
417 called when the DNS update has completed
419 static void dnsupdate_RODC_callback(struct tevent_req *req)
421 struct dnsupdate_RODC_state *st =
422 tevent_req_callback_data(req,
423 struct dnsupdate_RODC_state);
424 int sys_errno;
425 int i, ret;
427 ret = samba_runcmd_recv(req, &sys_errno);
428 talloc_free(req);
429 if (ret != 0) {
430 st->r->out.result = map_nt_error_from_unix_common(sys_errno);
431 DEBUG(2,(__location__ ": RODC DNS Update failed: %s\n", nt_errstr(st->r->out.result)));
432 } else {
433 st->r->out.result = NT_STATUS_OK;
434 DEBUG(3,(__location__ ": RODC DNS Update OK\n"));
437 for (i=0; i<st->r->in.dns_names->count; i++) {
438 st->r->out.dns_names->names[i].status = NT_STATUS_V(st->r->out.result);
441 irpc_send_reply(st->msg, NT_STATUS_OK);
446 * Called when we get a RODC DNS update request from the netlogon
447 * rpc server
449 static NTSTATUS dnsupdate_dnsupdate_RODC(struct irpc_message *msg,
450 struct dnsupdate_RODC *r)
452 struct dnsupdate_service *s = talloc_get_type(msg->private_data,
453 struct dnsupdate_service);
454 const char * const *dns_update_command = lpcfg_dns_update_command(s->task->lp_ctx);
455 struct dnsupdate_RODC_state *st;
456 struct tevent_req *req;
457 int i, ret;
458 struct GUID ntds_guid;
459 const char *site, *dnsdomain, *dnsforest, *ntdsguid, *hostname;
460 struct ldb_dn *sid_dn;
461 const char *attrs[] = { "dNSHostName", NULL };
462 struct ldb_result *res;
464 st = talloc_zero(msg, struct dnsupdate_RODC_state);
465 if (!st) {
466 r->out.result = NT_STATUS_NO_MEMORY;
467 return NT_STATUS_OK;
470 st->r = r;
471 st->msg = msg;
473 st->tmp_path = smbd_tmp_path(st, s->task->lp_ctx, "rodcdns.XXXXXX");
474 if (!st->tmp_path) {
475 talloc_free(st);
476 r->out.result = NT_STATUS_NO_MEMORY;
477 return NT_STATUS_OK;
480 st->fd = mkstemp(st->tmp_path);
481 if (st->fd == -1) {
482 DEBUG(0,("Unable to create a temporary file for RODC dnsupdate\n"));
483 talloc_free(st);
484 r->out.result = NT_STATUS_INTERNAL_DB_CORRUPTION;
485 return NT_STATUS_OK;
488 talloc_set_destructor(st, dnsupdate_RODC_destructor);
490 st->tmp_path2 = talloc_asprintf(st, "%s.cache", st->tmp_path);
491 if (!st->tmp_path2) {
492 talloc_free(st);
493 r->out.result = NT_STATUS_NO_MEMORY;
494 return NT_STATUS_OK;
497 sid_dn = ldb_dn_new_fmt(st, s->samdb, "<SID=%s>", dom_sid_string(st, r->in.dom_sid));
498 if (!sid_dn) {
499 talloc_free(st);
500 r->out.result = NT_STATUS_NO_MEMORY;
501 return NT_STATUS_OK;
504 /* work out the site */
505 ret = samdb_find_site_for_computer(s->samdb, st, sid_dn, &site);
506 if (ret != LDB_SUCCESS) {
507 DEBUG(2, (__location__ ": Unable to find site for computer %s\n",
508 ldb_dn_get_linearized(sid_dn)));
509 talloc_free(st);
510 r->out.result = NT_STATUS_NO_SUCH_USER;
511 return NT_STATUS_OK;
514 /* work out the ntdsguid */
515 ret = samdb_find_ntdsguid_for_computer(s->samdb, sid_dn, &ntds_guid);
516 ntdsguid = GUID_string(st, &ntds_guid);
517 if (ret != LDB_SUCCESS || !ntdsguid) {
518 DEBUG(2, (__location__ ": Unable to find NTDS GUID for computer %s\n",
519 ldb_dn_get_linearized(sid_dn)));
520 talloc_free(st);
521 r->out.result = NT_STATUS_NO_SUCH_USER;
522 return NT_STATUS_OK;
526 /* find dnsdomain and dnsforest */
527 dnsdomain = lpcfg_realm(s->task->lp_ctx);
528 dnsforest = dnsdomain;
530 /* find the hostname */
531 ret = dsdb_search_dn(s->samdb, st, &res, sid_dn, attrs, 0);
532 if (ret == LDB_SUCCESS) {
533 hostname = ldb_msg_find_attr_as_string(res->msgs[0], "dNSHostName", NULL);
535 if (ret != LDB_SUCCESS || !hostname) {
536 DEBUG(2, (__location__ ": Unable to find NTDS GUID for computer %s\n",
537 ldb_dn_get_linearized(sid_dn)));
538 talloc_free(st);
539 r->out.result = NT_STATUS_NO_SUCH_USER;
540 return NT_STATUS_OK;
544 for (i=0; i<st->r->in.dns_names->count; i++) {
545 struct NL_DNS_NAME_INFO *n = &r->in.dns_names->names[i];
546 switch (n->type) {
547 case NlDnsLdapAtSite:
548 dprintf(st->fd, "SRV _ldap._tcp.%s._sites.%s. %s %u\n",
549 site, dnsdomain, hostname, n->port);
550 break;
551 case NlDnsGcAtSite:
552 dprintf(st->fd, "SRV _ldap._tcp.%s._sites.gc._msdcs.%s. %s %u\n",
553 site, dnsdomain, hostname, n->port);
554 break;
555 case NlDnsDsaCname:
556 dprintf(st->fd, "CNAME %s._msdcs.%s. %s\n",
557 ntdsguid, dnsforest, hostname);
558 break;
559 case NlDnsKdcAtSite:
560 dprintf(st->fd, "SRV _kerberos._tcp.%s._sites.dc._msdcs.%s. %s %u\n",
561 site, dnsdomain, hostname, n->port);
562 break;
563 case NlDnsDcAtSite:
564 dprintf(st->fd, "SRV _ldap._tcp.%s._sites.dc._msdcs.%s. %s %u\n",
565 site, dnsdomain, hostname, n->port);
566 break;
567 case NlDnsRfc1510KdcAtSite:
568 dprintf(st->fd, "SRV _kerberos._tcp.%s._sites.%s. %s %u\n",
569 site, dnsdomain, hostname, n->port);
570 break;
571 case NlDnsGenericGcAtSite:
572 dprintf(st->fd, "SRV _gc._tcp.%s._sites.%s. %s %u\n",
573 site, dnsforest, hostname, n->port);
574 break;
578 close(st->fd);
579 st->fd = -1;
581 DEBUG(3,("Calling RODC DNS name update script %s\n", st->tmp_path));
582 req = samba_runcmd_send(st,
583 s->task->event_ctx,
584 timeval_current_ofs(20, 0),
585 2, 0,
586 dns_update_command,
587 "--update-list",
588 st->tmp_path,
589 "--update-cache",
590 st->tmp_path2,
591 NULL);
592 NT_STATUS_HAVE_NO_MEMORY(req);
594 /* setup the callback */
595 tevent_req_set_callback(req, dnsupdate_RODC_callback, st);
597 msg->defer_reply = true;
599 return NT_STATUS_OK;
603 startup the dns update task
605 static void dnsupdate_task_init(struct task_server *task)
607 NTSTATUS status;
608 struct dnsupdate_service *service;
610 if (lpcfg_server_role(task->lp_ctx) != ROLE_ACTIVE_DIRECTORY_DC) {
611 /* not useful for non-DC */
612 return;
615 task_server_set_title(task, "task[dnsupdate]");
617 service = talloc_zero(task, struct dnsupdate_service);
618 if (!service) {
619 task_server_terminate(task, "dnsupdate_task_init: out of memory", true);
620 return;
622 service->task = task;
623 task->private_data = service;
625 service->system_session_info = system_session(service->task->lp_ctx);
626 if (!service->system_session_info) {
627 task_server_terminate(task,
628 "dnsupdate: Failed to obtain server credentials\n",
629 true);
630 return;
633 service->samdb = samdb_connect(service, service->task->event_ctx, task->lp_ctx,
634 service->system_session_info, 0);
635 if (!service->samdb) {
636 task_server_terminate(task, "dnsupdate: Failed to connect to local samdb\n",
637 true);
638 return;
641 service->confupdate.interval = lpcfg_parm_int(task->lp_ctx, NULL,
642 "dnsupdate", "config interval", 60); /* in seconds */
644 service->nameupdate.interval = lpcfg_parm_int(task->lp_ctx, NULL,
645 "dnsupdate", "name interval", 600); /* in seconds */
647 dnsupdate_rebuild(service);
648 status = dnsupdate_confupdate_schedule(service);
649 if (!NT_STATUS_IS_OK(status)) {
650 task_server_terminate(task, talloc_asprintf(task,
651 "dnsupdate: Failed to confupdate schedule: %s\n",
652 nt_errstr(status)), true);
653 return;
656 dnsupdate_check_names(service);
657 status = dnsupdate_nameupdate_schedule(service);
658 if (!NT_STATUS_IS_OK(status)) {
659 task_server_terminate(task, talloc_asprintf(task,
660 "dnsupdate: Failed to nameupdate schedule: %s\n",
661 nt_errstr(status)), true);
662 return;
665 irpc_add_name(task->msg_ctx, "dnsupdate");
667 IRPC_REGISTER(task->msg_ctx, irpc, DNSUPDATE_RODC,
668 dnsupdate_dnsupdate_RODC, service);
670 /* create the intial file */
671 dnsupdate_rebuild(service);
676 register ourselves as a available server
678 NTSTATUS server_service_dnsupdate_init(void)
680 return register_server_service("dnsupdate", dnsupdate_task_init);