2 Unix SMB/CIFS implementation.
4 DNS server handler for update requests
6 Copyright (C) 2010 Kai Blin <kai@samba.org>
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/>.
23 #include "libcli/util/ntstatus.h"
24 #include "librpc/ndr/libndr.h"
25 #include "librpc/gen_ndr/ndr_dns.h"
26 #include "librpc/gen_ndr/ndr_dnsp.h"
28 #include "param/param.h"
29 #include "dsdb/samdb/samdb.h"
30 #include "dsdb/common/util.h"
31 #include "smbd/service_task.h"
32 #include "dns_server/dns_server.h"
33 #include "dns_server/dns_update.h"
35 static WERROR
dns_rr_to_dnsp(TALLOC_CTX
*mem_ctx
,
36 const struct dns_res_rec
*rrec
,
37 struct dnsp_DnssrvRpcRecord
*r
);
39 static WERROR
check_one_prerequisite(struct dns_server
*dns
,
41 const struct dns_name_question
*zone
,
42 const struct dns_res_rec
*pr
,
50 struct dnsp_DnssrvRpcRecord
*rec
= NULL
;
51 struct dnsp_DnssrvRpcRecord
*ans
;
54 size_t host_part_len
= 0;
59 return DNS_ERR(FORMAT_ERROR
);
62 match
= dns_name_match(zone
->name
, pr
->name
, &host_part_len
);
64 return DNS_ERR(NOTZONE
);
67 werror
= dns_name2dn(dns
, mem_ctx
, pr
->name
, &dn
);
68 W_ERROR_NOT_OK_RETURN(werror
);
70 if (pr
->rr_class
== DNS_QCLASS_ANY
) {
72 if (pr
->length
!= 0) {
73 return DNS_ERR(FORMAT_ERROR
);
77 if (pr
->rr_type
== DNS_QTYPE_ALL
) {
80 werror
= dns_lookup_records(dns
, mem_ctx
, dn
, &ans
, &acount
);
81 W_ERROR_NOT_OK_RETURN(werror
);
84 return DNS_ERR(NAME_ERROR
);
89 werror
= dns_lookup_records(dns
, mem_ctx
, dn
, &ans
, &acount
);
90 if (W_ERROR_EQUAL(werror
, DNS_ERR(NAME_ERROR
))) {
91 return DNS_ERR(NXRRSET
);
93 W_ERROR_NOT_OK_RETURN(werror
);
95 for (i
= 0; i
< acount
; i
++) {
96 if (ans
[i
].wType
== pr
->rr_type
) {
102 return DNS_ERR(NXRRSET
);
107 * RFC2136 3.2.5 doesn't actually mention the need to return
108 * OK here, but otherwise we'd always return a FORMAT_ERROR
109 * later on. This also matches Microsoft DNS behavior.
114 if (pr
->rr_class
== DNS_QCLASS_NONE
) {
115 if (pr
->length
!= 0) {
116 return DNS_ERR(FORMAT_ERROR
);
119 if (pr
->rr_type
== DNS_QTYPE_ALL
) {
122 werror
= dns_lookup_records(dns
, mem_ctx
, dn
, &ans
, &acount
);
123 if (W_ERROR_EQUAL(werror
, WERR_OK
)) {
124 return DNS_ERR(YXDOMAIN
);
129 werror
= dns_lookup_records(dns
, mem_ctx
, dn
, &ans
, &acount
);
130 if (W_ERROR_EQUAL(werror
, DNS_ERR(NAME_ERROR
))) {
136 for (i
= 0; i
< acount
; i
++) {
137 if (ans
[i
].wType
== pr
->rr_type
) {
143 return DNS_ERR(YXRRSET
);
148 * RFC2136 3.2.5 doesn't actually mention the need to return
149 * OK here, but otherwise we'd always return a FORMAT_ERROR
150 * later on. This also matches Microsoft DNS behavior.
155 if (pr
->rr_class
!= zone
->question_class
) {
156 return DNS_ERR(FORMAT_ERROR
);
159 *final_result
= false;
161 werror
= dns_lookup_records(dns
, mem_ctx
, dn
, &ans
, &acount
);
162 if (W_ERROR_EQUAL(werror
, DNS_ERR(NAME_ERROR
))) {
163 return DNS_ERR(NXRRSET
);
165 W_ERROR_NOT_OK_RETURN(werror
);
167 rec
= talloc_zero(mem_ctx
, struct dnsp_DnssrvRpcRecord
);
168 W_ERROR_HAVE_NO_MEMORY(rec
);
170 werror
= dns_rr_to_dnsp(rec
, pr
, rec
);
171 W_ERROR_NOT_OK_RETURN(werror
);
173 for (i
= 0; i
< acount
; i
++) {
174 if (dns_records_match(rec
, &ans
[i
])) {
181 return DNS_ERR(NXRRSET
);
187 static WERROR
check_prerequisites(struct dns_server
*dns
,
189 const struct dns_name_question
*zone
,
190 const struct dns_res_rec
*prereqs
, uint16_t count
)
193 WERROR final_error
= WERR_OK
;
195 for (i
= 0; i
< count
; i
++) {
199 werror
= check_one_prerequisite(dns
, mem_ctx
, zone
,
200 &prereqs
[i
], &final
);
201 if (!W_ERROR_IS_OK(werror
)) {
205 if (W_ERROR_IS_OK(final_error
)) {
206 final_error
= werror
;
211 if (!W_ERROR_IS_OK(final_error
)) {
218 static WERROR
update_prescan(const struct dns_name_question
*zone
,
219 const struct dns_res_rec
*updates
, uint16_t count
)
221 const struct dns_res_rec
*r
;
223 size_t host_part_len
;
226 for (i
= 0; i
< count
; i
++) {
228 match
= dns_name_match(zone
->name
, r
->name
, &host_part_len
);
230 return DNS_ERR(NOTZONE
);
232 if (zone
->question_class
== r
->rr_class
) {
233 if (r
->rr_type
== DNS_QTYPE_ALL
) {
234 return DNS_ERR(FORMAT_ERROR
);
236 if (r
->rr_type
== DNS_QTYPE_AXFR
) {
237 return DNS_ERR(FORMAT_ERROR
);
239 if (r
->rr_type
== DNS_QTYPE_MAILB
) {
240 return DNS_ERR(FORMAT_ERROR
);
242 if (r
->rr_type
== DNS_QTYPE_MAILA
) {
243 return DNS_ERR(FORMAT_ERROR
);
245 } else if (r
->rr_class
== DNS_QCLASS_ANY
) {
247 return DNS_ERR(FORMAT_ERROR
);
249 if (r
->length
!= 0) {
250 return DNS_ERR(FORMAT_ERROR
);
252 if (r
->rr_type
== DNS_QTYPE_AXFR
) {
253 return DNS_ERR(FORMAT_ERROR
);
255 if (r
->rr_type
== DNS_QTYPE_MAILB
) {
256 return DNS_ERR(FORMAT_ERROR
);
258 if (r
->rr_type
== DNS_QTYPE_MAILA
) {
259 return DNS_ERR(FORMAT_ERROR
);
261 } else if (r
->rr_class
== DNS_QCLASS_NONE
) {
263 return DNS_ERR(FORMAT_ERROR
);
265 if (r
->rr_type
== DNS_QTYPE_ALL
) {
266 return DNS_ERR(FORMAT_ERROR
);
268 if (r
->rr_type
== DNS_QTYPE_AXFR
) {
269 return DNS_ERR(FORMAT_ERROR
);
271 if (r
->rr_type
== DNS_QTYPE_MAILB
) {
272 return DNS_ERR(FORMAT_ERROR
);
274 if (r
->rr_type
== DNS_QTYPE_MAILA
) {
275 return DNS_ERR(FORMAT_ERROR
);
278 return DNS_ERR(FORMAT_ERROR
);
284 static WERROR
dns_rr_to_dnsp(TALLOC_CTX
*mem_ctx
,
285 const struct dns_res_rec
*rrec
,
286 struct dnsp_DnssrvRpcRecord
*r
)
288 if (rrec
->rr_type
== DNS_QTYPE_ALL
) {
289 return DNS_ERR(FORMAT_ERROR
);
294 r
->wType
= rrec
->rr_type
;
295 r
->dwTtlSeconds
= rrec
->ttl
;
296 r
->rank
= DNS_RANK_ZONE
;
297 /* TODO: Autogenerate this somehow */
300 /* If we get QCLASS_ANY, we're done here */
301 if (rrec
->rr_class
== DNS_QCLASS_ANY
) {
305 switch(rrec
->rr_type
) {
307 r
->data
.ipv4
= talloc_strdup(mem_ctx
, rrec
->rdata
.ipv4_record
);
308 W_ERROR_HAVE_NO_MEMORY(r
->data
.ipv4
);
311 r
->data
.ipv6
= talloc_strdup(mem_ctx
, rrec
->rdata
.ipv6_record
);
312 W_ERROR_HAVE_NO_MEMORY(r
->data
.ipv6
);
315 r
->data
.ns
= talloc_strdup(mem_ctx
, rrec
->rdata
.ns_record
);
316 W_ERROR_HAVE_NO_MEMORY(r
->data
.ns
);
318 case DNS_QTYPE_CNAME
:
319 r
->data
.cname
= talloc_strdup(mem_ctx
, rrec
->rdata
.cname_record
);
320 W_ERROR_HAVE_NO_MEMORY(r
->data
.cname
);
323 r
->data
.srv
.wPriority
= rrec
->rdata
.srv_record
.priority
;
324 r
->data
.srv
.wWeight
= rrec
->rdata
.srv_record
.weight
;
325 r
->data
.srv
.wPort
= rrec
->rdata
.srv_record
.port
;
326 r
->data
.srv
.nameTarget
= talloc_strdup(mem_ctx
,
327 rrec
->rdata
.srv_record
.target
);
328 W_ERROR_HAVE_NO_MEMORY(r
->data
.srv
.nameTarget
);
331 r
->data
.mx
.wPriority
= rrec
->rdata
.mx_record
.preference
;
332 r
->data
.mx
.nameTarget
= talloc_strdup(mem_ctx
,
333 rrec
->rdata
.mx_record
.exchange
);
334 W_ERROR_HAVE_NO_MEMORY(r
->data
.mx
.nameTarget
);
337 r
->data
.txt
= talloc_strdup(mem_ctx
, rrec
->rdata
.txt_record
.txt
);
338 W_ERROR_HAVE_NO_MEMORY(r
->data
.txt
);
341 DEBUG(0, ("Got a qytpe of %d\n", rrec
->rr_type
));
342 return DNS_ERR(NOT_IMPLEMENTED
);
351 static WERROR
handle_one_update(struct dns_server
*dns
,
353 const struct dns_name_question
*zone
,
354 const struct dns_res_rec
*update
)
356 struct dnsp_DnssrvRpcRecord
*recs
= NULL
;
361 bool needs_add
= false;
363 DEBUG(1, ("Looking at record: \n"));
364 NDR_PRINT_DEBUG(dns_res_rec
, discard_const(update
));
366 switch (update
->rr_type
) {
371 case DNS_QTYPE_CNAME
:
386 return DNS_ERR(NOT_IMPLEMENTED
);
389 werror
= dns_name2dn(dns
, mem_ctx
, update
->name
, &dn
);
390 W_ERROR_NOT_OK_RETURN(werror
);
392 werror
= dns_lookup_records(dns
, mem_ctx
, dn
, &recs
, &rcount
);
393 if (W_ERROR_EQUAL(werror
, DNS_ERR(NAME_ERROR
))) {
399 W_ERROR_NOT_OK_RETURN(werror
);
401 if (update
->rr_class
== zone
->question_class
) {
402 if (update
->rr_type
== DNS_QTYPE_CNAME
) {
404 * If there is a record in the directory
405 * that's not a CNAME, ignore update
407 for (i
= 0; i
< rcount
; i
++) {
408 if (recs
[i
].wType
!= DNS_TYPE_CNAME
) {
409 DEBUG(0, ("Skipping update\n"));
416 * There should be no entries besides one CNAME record
417 * per name, so replace everything with the new CNAME
421 recs
= talloc_realloc(mem_ctx
, recs
,
422 struct dnsp_DnssrvRpcRecord
, rcount
);
423 W_ERROR_HAVE_NO_MEMORY(recs
);
425 werror
= dns_rr_to_dnsp(recs
, update
, &recs
[0]);
426 W_ERROR_NOT_OK_RETURN(werror
);
428 werror
= dns_replace_records(dns
, mem_ctx
, dn
,
429 needs_add
, recs
, rcount
);
430 W_ERROR_NOT_OK_RETURN(werror
);
435 * If there is a CNAME record for this name,
438 for (i
= 0; i
< rcount
; i
++) {
439 if (recs
[i
].wType
== DNS_TYPE_CNAME
) {
440 DEBUG(0, ("Skipping update\n"));
445 if (update
->rr_type
== DNS_QTYPE_SOA
) {
449 * If the zone has no SOA record?? or update's
450 * serial number is smaller than existing SOA's,
453 for (i
= 0; i
< rcount
; i
++) {
454 if (recs
[i
].wType
== DNS_TYPE_SOA
) {
457 n
= update
->rdata
.soa_record
.serial
;
458 o
= recs
[i
].data
.soa
.serial
;
460 * TODO: Implement RFC 1982 comparison
464 DEBUG(0, ("Skipping update\n"));
472 DEBUG(0, ("Skipping update\n"));
476 werror
= dns_rr_to_dnsp(mem_ctx
, update
, &recs
[i
]);
477 W_ERROR_NOT_OK_RETURN(werror
);
479 for (i
++; i
< rcount
; i
++) {
480 if (recs
[i
].wType
!= DNS_TYPE_SOA
) {
484 ZERO_STRUCT(recs
[i
]);
487 werror
= dns_replace_records(dns
, mem_ctx
, dn
,
488 needs_add
, recs
, rcount
);
489 W_ERROR_NOT_OK_RETURN(werror
);
494 recs
= talloc_realloc(mem_ctx
, recs
,
495 struct dnsp_DnssrvRpcRecord
, rcount
+1);
496 W_ERROR_HAVE_NO_MEMORY(recs
);
498 werror
= dns_rr_to_dnsp(recs
, update
, &recs
[rcount
]);
499 W_ERROR_NOT_OK_RETURN(werror
);
501 for (i
= 0; i
< rcount
; i
++) {
502 if (!dns_records_match(&recs
[i
], &recs
[rcount
])) {
506 recs
[i
] = recs
[rcount
];
508 werror
= dns_replace_records(dns
, mem_ctx
, dn
,
509 needs_add
, recs
, rcount
);
510 W_ERROR_NOT_OK_RETURN(werror
);
515 werror
= dns_replace_records(dns
, mem_ctx
, dn
,
516 needs_add
, recs
, rcount
+1);
517 W_ERROR_NOT_OK_RETURN(werror
);
520 } else if (update
->rr_class
== DNS_QCLASS_ANY
) {
521 if (update
->rr_type
== DNS_QTYPE_ALL
) {
522 if (dns_name_equal(update
->name
, zone
->name
)) {
523 for (i
= 0; i
< rcount
; i
++) {
525 if (recs
[i
].wType
== DNS_TYPE_SOA
) {
529 if (recs
[i
].wType
== DNS_TYPE_NS
) {
533 ZERO_STRUCT(recs
[i
]);
537 for (i
= 0; i
< rcount
; i
++) {
538 ZERO_STRUCT(recs
[i
]);
542 } else if (dns_name_equal(update
->name
, zone
->name
)) {
544 if (update
->rr_type
== DNS_QTYPE_SOA
) {
548 if (update
->rr_type
== DNS_QTYPE_NS
) {
552 for (i
= 0; i
< rcount
; i
++) {
553 if (recs
[i
].wType
== update
->rr_type
) {
554 ZERO_STRUCT(recs
[i
]);
558 werror
= dns_replace_records(dns
, mem_ctx
, dn
,
559 needs_add
, recs
, rcount
);
560 W_ERROR_NOT_OK_RETURN(werror
);
563 } else if (update
->rr_class
== DNS_QCLASS_NONE
) {
564 struct dnsp_DnssrvRpcRecord
*del_rec
;
566 if (update
->rr_type
== DNS_QTYPE_SOA
) {
569 if (update
->rr_type
== DNS_QTYPE_NS
) {
571 struct dnsp_DnssrvRpcRecord
*ns_rec
= talloc(mem_ctx
,
572 struct dnsp_DnssrvRpcRecord
);
573 W_ERROR_HAVE_NO_MEMORY(ns_rec
);
576 werror
= dns_rr_to_dnsp(ns_rec
, update
, ns_rec
);
577 W_ERROR_NOT_OK_RETURN(werror
);
579 for (i
= 0; i
< rcount
; i
++) {
580 if (dns_records_match(ns_rec
, &recs
[i
])) {
590 del_rec
= talloc(mem_ctx
, struct dnsp_DnssrvRpcRecord
);
591 W_ERROR_HAVE_NO_MEMORY(del_rec
);
593 werror
= dns_rr_to_dnsp(del_rec
, update
, del_rec
);
594 W_ERROR_NOT_OK_RETURN(werror
);
596 for (i
= 0; i
< rcount
; i
++) {
597 if (dns_records_match(del_rec
, &recs
[i
])) {
598 ZERO_STRUCT(recs
[i
]);
606 static WERROR
handle_updates(struct dns_server
*dns
,
608 const struct dns_name_question
*zone
,
609 const struct dns_res_rec
*prereqs
, uint16_t pcount
,
610 struct dns_res_rec
*updates
, uint16_t upd_count
)
612 struct ldb_dn
*zone_dn
= NULL
;
613 WERROR werror
= WERR_OK
;
616 TALLOC_CTX
*tmp_ctx
= talloc_new(mem_ctx
);
618 werror
= dns_name2dn(dns
, tmp_ctx
, zone
->name
, &zone_dn
);
619 W_ERROR_NOT_OK_RETURN(werror
);
621 ret
= ldb_transaction_start(dns
->samdb
);
622 if (ret
!= LDB_SUCCESS
) {
623 return DNS_ERR(SERVER_FAILURE
);
626 werror
= check_prerequisites(dns
, tmp_ctx
, zone
, prereqs
, pcount
);
627 W_ERROR_NOT_OK_GOTO(werror
, failed
);
629 DEBUG(0, ("update count is %u\n", upd_count
));
631 for (ri
= 0; ri
< upd_count
; ri
++) {
632 werror
= handle_one_update(dns
, tmp_ctx
, zone
,
634 W_ERROR_NOT_OK_GOTO(werror
, failed
);
637 ldb_transaction_commit(dns
->samdb
);
638 TALLOC_FREE(tmp_ctx
);
642 ldb_transaction_cancel(dns
->samdb
);
643 TALLOC_FREE(tmp_ctx
);
648 WERROR
dns_server_process_update(struct dns_server
*dns
,
650 struct dns_name_packet
*in
,
651 struct dns_res_rec
**prereqs
, uint16_t *prereq_count
,
652 struct dns_res_rec
**updates
, uint16_t *update_count
,
653 struct dns_res_rec
**additional
, uint16_t *arcount
)
655 struct dns_name_question
*zone
;
656 const struct dns_server_zone
*z
;
657 size_t host_part_len
= 0;
658 WERROR werror
= DNS_ERR(NOT_IMPLEMENTED
);
660 if (in
->qdcount
!= 1) {
661 return DNS_ERR(FORMAT_ERROR
);
664 zone
= &in
->questions
[0];
666 if (zone
->question_class
!= DNS_QCLASS_IN
&&
667 zone
->question_class
!= DNS_QCLASS_ANY
) {
668 return DNS_ERR(NOT_IMPLEMENTED
);
671 if (zone
->question_type
!= DNS_QTYPE_SOA
) {
672 return DNS_ERR(FORMAT_ERROR
);
675 DEBUG(0, ("Got a dns update request.\n"));
677 for (z
= dns
->zones
; z
!= NULL
; z
= z
->next
) {
680 match
= dns_name_match(z
->name
, zone
->name
, &host_part_len
);
687 DEBUG(0, ("We're not authorative for this zone\n"));
688 return DNS_ERR(NOTAUTH
);
691 if (host_part_len
!= 0) {
692 /* TODO: We need to delegate this one */
693 DEBUG(0, ("Would have to delegate zones.\n"));
694 return DNS_ERR(NOT_IMPLEMENTED
);
697 *prereq_count
= in
->ancount
;
698 *prereqs
= in
->answers
;
699 werror
= check_prerequisites(dns
, mem_ctx
, in
->questions
, *prereqs
,
701 W_ERROR_NOT_OK_RETURN(werror
);
703 /* TODO: Check if update is allowed, we probably want "always",
704 * key-based GSSAPI, key-based bind-style TSIG and "never" as
705 * smb.conf options. */
706 if (lpcfg_allow_dns_updates(dns
->task
->lp_ctx
) != DNS_UPDATE_ON
) {
707 DEBUG(0, ("Update not allowed."));
708 return DNS_ERR(REFUSED
);
711 *update_count
= in
->nscount
;
712 *updates
= in
->nsrecs
;
713 werror
= update_prescan(in
->questions
, *updates
, *update_count
);
714 W_ERROR_NOT_OK_RETURN(werror
);
717 werror
= handle_updates(dns
, mem_ctx
, in
->questions
, *prereqs
,
718 *prereq_count
, *updates
, *update_count
);
719 W_ERROR_NOT_OK_RETURN(werror
);