2 Unix SMB/CIFS implementation.
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 "smbd/service_task.h"
24 #include "smbd/service.h"
25 #include "smbd/service_stream.h"
26 #include "smbd/process_model.h"
27 #include "lib/events/events.h"
28 #include "lib/socket/socket.h"
29 #include "lib/tsocket/tsocket.h"
30 #include "libcli/util/tstream.h"
31 #include "libcli/util/ntstatus.h"
32 #include "system/network.h"
33 #include "lib/stream/packet.h"
34 #include "lib/socket/netif.h"
35 #include "dns_server/dns_server.h"
36 #include "param/param.h"
37 #include "librpc/ndr/libndr.h"
38 #include "librpc/gen_ndr/ndr_dns.h"
39 #include "librpc/gen_ndr/ndr_dnsp.h"
41 #include "dsdb/samdb/samdb.h"
42 #include "dsdb/common/util.h"
43 #include "auth/session.h"
44 #include "lib/util/dlinklist.h"
45 #include "lib/util/tevent_werror.h"
46 #include "auth/auth.h"
47 #include "auth/credentials/credentials.h"
49 NTSTATUS
server_service_dns_init(void);
51 /* hold information about one dns socket */
53 struct dns_server
*dns
;
54 struct tsocket_address
*local_address
;
57 struct dns_udp_socket
{
58 struct dns_socket
*dns_socket
;
59 struct tdgram_context
*dgram
;
60 struct tevent_queue
*send_queue
;
64 state of an open tcp connection
66 struct dns_tcp_connection
{
67 /* stream connection we belong to */
68 struct stream_connection
*conn
;
70 /* the dns_server the connection belongs to */
71 struct dns_socket
*dns_socket
;
73 struct tstream_context
*tstream
;
75 struct tevent_queue
*send_queue
;
78 static void dns_tcp_terminate_connection(struct dns_tcp_connection
*dnsconn
, const char *reason
)
80 stream_terminate_connection(dnsconn
->conn
, reason
);
83 static void dns_tcp_recv(struct stream_connection
*conn
, uint16_t flags
)
85 struct dns_tcp_connection
*dnsconn
= talloc_get_type(conn
->private_data
,
86 struct dns_tcp_connection
);
87 /* this should never be triggered! */
88 dns_tcp_terminate_connection(dnsconn
, "dns_tcp_recv: called");
91 static void dns_tcp_send(struct stream_connection
*conn
, uint16_t flags
)
93 struct dns_tcp_connection
*dnsconn
= talloc_get_type(conn
->private_data
,
94 struct dns_tcp_connection
);
95 /* this should never be triggered! */
96 dns_tcp_terminate_connection(dnsconn
, "dns_tcp_send: called");
99 struct dns_process_state
{
101 struct dns_name_packet in_packet
;
102 struct dns_request_state state
;
104 struct dns_name_packet out_packet
;
108 static void dns_process_done(struct tevent_req
*subreq
);
110 static struct tevent_req
*dns_process_send(TALLOC_CTX
*mem_ctx
,
111 struct tevent_context
*ev
,
112 struct dns_server
*dns
,
115 struct tevent_req
*req
, *subreq
;
116 struct dns_process_state
*state
;
117 enum ndr_err_code ndr_err
;
120 req
= tevent_req_create(mem_ctx
, &state
, struct dns_process_state
);
126 if (in
->length
< 12) {
127 tevent_req_werror(req
, WERR_INVALID_PARAM
);
128 return tevent_req_post(req
, ev
);
130 dump_data(8, in
->data
, in
->length
);
132 ndr_err
= ndr_pull_struct_blob(
133 in
, state
, &state
->in_packet
,
134 (ndr_pull_flags_fn_t
)ndr_pull_dns_name_packet
);
136 if (!NDR_ERR_CODE_IS_SUCCESS(ndr_err
)) {
137 state
->dns_err
= DNS_RCODE_FORMERR
;
138 tevent_req_done(req
);
139 return tevent_req_post(req
, ev
);
142 NDR_PRINT_DEBUG(dns_name_packet
, &state
->in_packet
);
145 state
->state
.flags
= state
->in_packet
.operation
;
146 state
->state
.flags
|= DNS_FLAG_REPLY
;
148 if (lpcfg_dns_recursive_queries(dns
->task
->lp_ctx
)) {
149 state
->state
.flags
|= DNS_FLAG_RECURSION_AVAIL
;
152 state
->out_packet
= state
->in_packet
;
154 switch (state
->in_packet
.operation
& DNS_OPCODE
) {
155 case DNS_OPCODE_QUERY
:
156 subreq
= dns_server_process_query_send(
157 state
, ev
, dns
, &state
->state
, &state
->in_packet
);
158 if (tevent_req_nomem(subreq
, req
)) {
159 return tevent_req_post(req
, ev
);
161 tevent_req_set_callback(subreq
, dns_process_done
, req
);
163 case DNS_OPCODE_UPDATE
:
164 ret
= dns_server_process_update(
165 dns
, &state
->state
, state
, &state
->in_packet
,
166 &state
->out_packet
.answers
, &state
->out_packet
.ancount
,
167 &state
->out_packet
.nsrecs
, &state
->out_packet
.nscount
,
168 &state
->out_packet
.additional
,
169 &state
->out_packet
.arcount
);
172 ret
= WERR_DNS_ERROR_RCODE_NOT_IMPLEMENTED
;
174 if (!W_ERROR_IS_OK(ret
)) {
175 state
->dns_err
= werr_to_dns_err(ret
);
177 tevent_req_done(req
);
178 return tevent_req_post(req
, ev
);
181 static void dns_process_done(struct tevent_req
*subreq
)
183 struct tevent_req
*req
= tevent_req_callback_data(
184 subreq
, struct tevent_req
);
185 struct dns_process_state
*state
= tevent_req_data(
186 req
, struct dns_process_state
);
189 ret
= dns_server_process_query_recv(
191 &state
->out_packet
.answers
, &state
->out_packet
.ancount
,
192 &state
->out_packet
.nsrecs
, &state
->out_packet
.nscount
,
193 &state
->out_packet
.additional
, &state
->out_packet
.arcount
);
196 if (!W_ERROR_IS_OK(ret
)) {
197 state
->dns_err
= werr_to_dns_err(ret
);
199 tevent_req_done(req
);
202 static WERROR
dns_process_recv(struct tevent_req
*req
, TALLOC_CTX
*mem_ctx
,
205 struct dns_process_state
*state
= tevent_req_data(
206 req
, struct dns_process_state
);
207 enum ndr_err_code ndr_err
;
210 if (tevent_req_is_werror(req
, &ret
)) {
213 if (state
->dns_err
!= DNS_RCODE_OK
) {
216 state
->out_packet
.operation
|= state
->state
.flags
;
218 ndr_err
= ndr_push_struct_blob(
219 out
, mem_ctx
, &state
->out_packet
,
220 (ndr_push_flags_fn_t
)ndr_push_dns_name_packet
);
221 if (!NDR_ERR_CODE_IS_SUCCESS(ndr_err
)) {
222 DEBUG(1, ("Failed to push packet: %s!\n",
223 ndr_errstr(ndr_err
)));
224 state
->dns_err
= DNS_RCODE_SERVFAIL
;
230 *out
= data_blob_talloc(mem_ctx
, state
->in
->data
, state
->in
->length
);
231 if (out
->data
== NULL
) {
234 out
->data
[2] |= 0x80; /* Toggle DNS_FLAG_REPLY */
235 out
->data
[3] |= state
->dns_err
;
239 struct dns_tcp_call
{
240 struct dns_tcp_connection
*dns_conn
;
244 struct iovec out_iov
[2];
247 static void dns_tcp_call_process_done(struct tevent_req
*subreq
);
248 static void dns_tcp_call_writev_done(struct tevent_req
*subreq
);
250 static void dns_tcp_call_loop(struct tevent_req
*subreq
)
252 struct dns_tcp_connection
*dns_conn
= tevent_req_callback_data(subreq
,
253 struct dns_tcp_connection
);
254 struct dns_server
*dns
= dns_conn
->dns_socket
->dns
;
255 struct dns_tcp_call
*call
;
258 call
= talloc(dns_conn
, struct dns_tcp_call
);
260 dns_tcp_terminate_connection(dns_conn
, "dns_tcp_call_loop: "
261 "no memory for dns_tcp_call");
264 call
->dns_conn
= dns_conn
;
266 status
= tstream_read_pdu_blob_recv(subreq
,
270 if (!NT_STATUS_IS_OK(status
)) {
273 reason
= talloc_asprintf(call
, "dns_tcp_call_loop: "
274 "tstream_read_pdu_blob_recv() - %s",
277 reason
= nt_errstr(status
);
280 dns_tcp_terminate_connection(dns_conn
, reason
);
284 DEBUG(10,("Received DNS TCP packet of length %lu from %s\n",
285 (long) call
->in
.length
,
286 tsocket_address_string(dns_conn
->conn
->remote_address
, call
)));
288 /* skip length header */
290 call
->in
.length
-= 2;
292 subreq
= dns_process_send(call
, dns
->task
->event_ctx
, dns
,
294 if (subreq
== NULL
) {
295 dns_tcp_terminate_connection(
296 dns_conn
, "dns_tcp_call_loop: dns_process_send "
300 tevent_req_set_callback(subreq
, dns_tcp_call_process_done
, call
);
303 * The dns tcp pdu's has the length as 2 byte (initial_read_size),
304 * packet_full_request_u16 provides the pdu length then.
306 subreq
= tstream_read_pdu_blob_send(dns_conn
,
307 dns_conn
->conn
->event
.ctx
,
309 2, /* initial_read_size */
310 packet_full_request_u16
,
312 if (subreq
== NULL
) {
313 dns_tcp_terminate_connection(dns_conn
, "dns_tcp_call_loop: "
314 "no memory for tstream_read_pdu_blob_send");
317 tevent_req_set_callback(subreq
, dns_tcp_call_loop
, dns_conn
);
320 static void dns_tcp_call_process_done(struct tevent_req
*subreq
)
322 struct dns_tcp_call
*call
= tevent_req_callback_data(subreq
,
323 struct dns_tcp_call
);
324 struct dns_tcp_connection
*dns_conn
= call
->dns_conn
;
327 err
= dns_process_recv(subreq
, call
, &call
->out
);
329 if (!W_ERROR_IS_OK(err
)) {
330 DEBUG(1, ("dns_process returned %s\n", win_errstr(err
)));
331 dns_tcp_terminate_connection(dns_conn
,
332 "dns_tcp_call_loop: process function failed");
336 /* First add the length of the out buffer */
337 RSSVAL(call
->out_hdr
, 0, call
->out
.length
);
338 call
->out_iov
[0].iov_base
= (char *) call
->out_hdr
;
339 call
->out_iov
[0].iov_len
= 2;
341 call
->out_iov
[1].iov_base
= (char *) call
->out
.data
;
342 call
->out_iov
[1].iov_len
= call
->out
.length
;
344 subreq
= tstream_writev_queue_send(call
,
345 dns_conn
->conn
->event
.ctx
,
347 dns_conn
->send_queue
,
349 if (subreq
== NULL
) {
350 dns_tcp_terminate_connection(dns_conn
, "dns_tcp_call_loop: "
351 "no memory for tstream_writev_queue_send");
354 tevent_req_set_callback(subreq
, dns_tcp_call_writev_done
, call
);
357 static void dns_tcp_call_writev_done(struct tevent_req
*subreq
)
359 struct dns_tcp_call
*call
= tevent_req_callback_data(subreq
,
360 struct dns_tcp_call
);
364 rc
= tstream_writev_queue_recv(subreq
, &sys_errno
);
369 reason
= talloc_asprintf(call
, "dns_tcp_call_writev_done: "
370 "tstream_writev_queue_recv() - %d:%s",
371 sys_errno
, strerror(sys_errno
));
373 reason
= "dns_tcp_call_writev_done: tstream_writev_queue_recv() failed";
376 dns_tcp_terminate_connection(call
->dns_conn
, reason
);
380 /* We don't care about errors */
386 called when we get a new connection
388 static void dns_tcp_accept(struct stream_connection
*conn
)
390 struct dns_socket
*dns_socket
;
391 struct dns_tcp_connection
*dns_conn
;
392 struct tevent_req
*subreq
;
395 dns_conn
= talloc_zero(conn
, struct dns_tcp_connection
);
396 if (dns_conn
== NULL
) {
397 stream_terminate_connection(conn
,
398 "dns_tcp_accept: out of memory");
402 dns_conn
->send_queue
= tevent_queue_create(conn
, "dns_tcp_accept");
403 if (dns_conn
->send_queue
== NULL
) {
404 stream_terminate_connection(conn
,
405 "dns_tcp_accept: out of memory");
409 dns_socket
= talloc_get_type(conn
->private_data
, struct dns_socket
);
411 TALLOC_FREE(conn
->event
.fde
);
413 rc
= tstream_bsd_existing_socket(dns_conn
,
414 socket_get_fd(conn
->socket
),
417 stream_terminate_connection(conn
,
418 "dns_tcp_accept: out of memory");
422 dns_conn
->conn
= conn
;
423 dns_conn
->dns_socket
= dns_socket
;
424 conn
->private_data
= dns_conn
;
427 * The dns tcp pdu's has the length as 2 byte (initial_read_size),
428 * packet_full_request_u16 provides the pdu length then.
430 subreq
= tstream_read_pdu_blob_send(dns_conn
,
431 dns_conn
->conn
->event
.ctx
,
433 2, /* initial_read_size */
434 packet_full_request_u16
,
436 if (subreq
== NULL
) {
437 dns_tcp_terminate_connection(dns_conn
, "dns_tcp_accept: "
438 "no memory for tstream_read_pdu_blob_send");
441 tevent_req_set_callback(subreq
, dns_tcp_call_loop
, dns_conn
);
444 static const struct stream_server_ops dns_tcp_stream_ops
= {
446 .accept_connection
= dns_tcp_accept
,
447 .recv_handler
= dns_tcp_recv
,
448 .send_handler
= dns_tcp_send
451 struct dns_udp_call
{
452 struct dns_udp_socket
*sock
;
453 struct tsocket_address
*src
;
458 static void dns_udp_call_process_done(struct tevent_req
*subreq
);
459 static void dns_udp_call_sendto_done(struct tevent_req
*subreq
);
461 static void dns_udp_call_loop(struct tevent_req
*subreq
)
463 struct dns_udp_socket
*sock
= tevent_req_callback_data(subreq
,
464 struct dns_udp_socket
);
465 struct dns_server
*dns
= sock
->dns_socket
->dns
;
466 struct dns_udp_call
*call
;
471 call
= talloc(sock
, struct dns_udp_call
);
478 len
= tdgram_recvfrom_recv(subreq
, &sys_errno
,
479 call
, &buf
, &call
->src
);
487 call
->in
.length
= len
;
489 DEBUG(10,("Received DNS UDP packet of length %lu from %s\n",
490 (long)call
->in
.length
,
491 tsocket_address_string(call
->src
, call
)));
493 subreq
= dns_process_send(call
, dns
->task
->event_ctx
, dns
,
495 if (subreq
== NULL
) {
499 tevent_req_set_callback(subreq
, dns_udp_call_process_done
, call
);
502 subreq
= tdgram_recvfrom_send(sock
,
503 sock
->dns_socket
->dns
->task
->event_ctx
,
505 if (subreq
== NULL
) {
506 task_server_terminate(sock
->dns_socket
->dns
->task
,
507 "no memory for tdgram_recvfrom_send",
511 tevent_req_set_callback(subreq
, dns_udp_call_loop
, sock
);
514 static void dns_udp_call_process_done(struct tevent_req
*subreq
)
516 struct dns_udp_call
*call
= tevent_req_callback_data(
517 subreq
, struct dns_udp_call
);
518 struct dns_udp_socket
*sock
= call
->sock
;
519 struct dns_server
*dns
= sock
->dns_socket
->dns
;
522 err
= dns_process_recv(subreq
, call
, &call
->out
);
524 if (!W_ERROR_IS_OK(err
)) {
525 DEBUG(1, ("dns_process returned %s\n", win_errstr(err
)));
530 subreq
= tdgram_sendto_queue_send(call
,
531 dns
->task
->event_ctx
,
537 if (subreq
== NULL
) {
541 tevent_req_set_callback(subreq
, dns_udp_call_sendto_done
, call
);
544 static void dns_udp_call_sendto_done(struct tevent_req
*subreq
)
546 struct dns_udp_call
*call
= tevent_req_callback_data(subreq
,
547 struct dns_udp_call
);
551 ret
= tdgram_sendto_queue_recv(subreq
, &sys_errno
);
553 /* We don't care about errors */
559 start listening on the given address
561 static NTSTATUS
dns_add_socket(struct dns_server
*dns
,
562 const struct model_ops
*model_ops
,
567 struct dns_socket
*dns_socket
;
568 struct dns_udp_socket
*dns_udp_socket
;
569 struct tevent_req
*udpsubreq
;
573 dns_socket
= talloc(dns
, struct dns_socket
);
574 NT_STATUS_HAVE_NO_MEMORY(dns_socket
);
576 dns_socket
->dns
= dns
;
578 ret
= tsocket_address_inet_from_strings(dns_socket
, "ip",
580 &dns_socket
->local_address
);
582 status
= map_nt_error_from_unix_common(errno
);
586 status
= stream_setup_socket(dns
->task
,
587 dns
->task
->event_ctx
,
591 "ip", address
, &port
,
592 lpcfg_socket_options(dns
->task
->lp_ctx
),
594 if (!NT_STATUS_IS_OK(status
)) {
595 DEBUG(0,("Failed to bind to %s:%u TCP - %s\n",
596 address
, port
, nt_errstr(status
)));
597 talloc_free(dns_socket
);
601 dns_udp_socket
= talloc(dns_socket
, struct dns_udp_socket
);
602 NT_STATUS_HAVE_NO_MEMORY(dns_udp_socket
);
604 dns_udp_socket
->dns_socket
= dns_socket
;
606 ret
= tdgram_inet_udp_socket(dns_socket
->local_address
,
609 &dns_udp_socket
->dgram
);
611 status
= map_nt_error_from_unix_common(errno
);
612 DEBUG(0,("Failed to bind to %s:%u UDP - %s\n",
613 address
, port
, nt_errstr(status
)));
617 dns_udp_socket
->send_queue
= tevent_queue_create(dns_udp_socket
,
618 "dns_udp_send_queue");
619 NT_STATUS_HAVE_NO_MEMORY(dns_udp_socket
->send_queue
);
621 udpsubreq
= tdgram_recvfrom_send(dns_udp_socket
,
622 dns
->task
->event_ctx
,
623 dns_udp_socket
->dgram
);
624 NT_STATUS_HAVE_NO_MEMORY(udpsubreq
);
625 tevent_req_set_callback(udpsubreq
, dns_udp_call_loop
, dns_udp_socket
);
631 setup our listening sockets on the configured network interfaces
633 static NTSTATUS
dns_startup_interfaces(struct dns_server
*dns
, struct loadparm_context
*lp_ctx
,
634 struct interface
*ifaces
)
636 const struct model_ops
*model_ops
;
638 TALLOC_CTX
*tmp_ctx
= talloc_new(dns
);
642 /* within the dns task we want to be a single process, so
643 ask for the single process model ops and pass these to the
644 stream_setup_socket() call. */
645 model_ops
= process_model_startup("single");
647 DEBUG(0,("Can't find 'single' process model_ops\n"));
648 return NT_STATUS_INTERNAL_ERROR
;
651 num_interfaces
= iface_list_count(ifaces
);
653 for (i
=0; i
<num_interfaces
; i
++) {
654 const char *address
= talloc_strdup(tmp_ctx
, iface_list_n_ip(ifaces
, i
));
656 status
= dns_add_socket(dns
, model_ops
, "dns", address
, DNS_SERVICE_PORT
);
657 NT_STATUS_NOT_OK_RETURN(status
);
660 talloc_free(tmp_ctx
);
665 static int dns_server_sort_zones(struct ldb_message
**m1
, struct ldb_message
**m2
)
670 n1
= ldb_msg_find_attr_as_string(*m1
, "name", NULL
);
671 n2
= ldb_msg_find_attr_as_string(*m2
, "name", NULL
);
676 /* If the string lengths are not equal just sort by length */
678 /* If m1 is the larger zone name, return it first */
682 /*TODO: We need to compare DNs here, we want the DomainDNSZones first */
686 static struct dns_server_tkey_store
*tkey_store_init(TALLOC_CTX
*mem_ctx
,
689 struct dns_server_tkey_store
*buffer
= talloc_zero(mem_ctx
,
690 struct dns_server_tkey_store
);
692 if (buffer
== NULL
) {
697 buffer
->next_idx
= 0;
699 buffer
->tkeys
= talloc_zero_array(buffer
, struct dns_server_tkey
*, size
);
700 if (buffer
->tkeys
== NULL
) {
707 static void dns_task_init(struct task_server
*task
)
709 struct dns_server
*dns
;
711 struct interface
*ifaces
;
713 struct ldb_result
*res
;
714 static const char * const attrs
[] = { "name", NULL
};
717 switch (lpcfg_server_role(task
->lp_ctx
)) {
718 case ROLE_STANDALONE
:
719 task_server_terminate(task
, "dns: no DNS required in standalone configuration", false);
721 case ROLE_DOMAIN_MEMBER
:
722 task_server_terminate(task
, "dns: no DNS required in member server configuration", false);
724 case ROLE_ACTIVE_DIRECTORY_DC
:
725 /* Yes, we want a DNS */
729 load_interface_list(task
, task
->lp_ctx
, &ifaces
);
731 if (iface_list_count(ifaces
) == 0) {
732 task_server_terminate(task
, "dns: no network interfaces configured", false);
736 task_server_set_title(task
, "task[dns]");
738 dns
= talloc_zero(task
, struct dns_server
);
740 task_server_terminate(task
, "dns: out of memory", true);
746 dns
->server_credentials
= cli_credentials_init(dns
);
747 if (!dns
->server_credentials
) {
748 task_server_terminate(task
, "Failed to init server credentials\n", true);
752 cli_credentials_set_conf(dns
->server_credentials
, task
->lp_ctx
);
753 status
= cli_credentials_set_machine_account(dns
->server_credentials
, task
->lp_ctx
);
754 if (!NT_STATUS_IS_OK(status
)) {
755 task_server_terminate(task
,
756 talloc_asprintf(task
, "Failed to obtain server credentials, perhaps a standalone server?: %s\n",
762 dns
->tkeys
= tkey_store_init(dns
, TKEY_BUFFER_SIZE
);
764 task_server_terminate(task
, "Failed to allocate tkey storage\n", true);
768 dns
->samdb
= samdb_connect(dns
, dns
->task
->event_ctx
, dns
->task
->lp_ctx
,
769 system_session(dns
->task
->lp_ctx
), 0);
771 task_server_terminate(task
, "dns: samdb_connect failed", true);
775 // TODO: this search does not work against windows
776 ret
= dsdb_search(dns
->samdb
, dns
, &res
, NULL
, LDB_SCOPE_SUBTREE
,
777 attrs
, DSDB_SEARCH_SEARCH_ALL_PARTITIONS
, "(objectClass=dnsZone)");
778 if (ret
!= LDB_SUCCESS
) {
779 task_server_terminate(task
,
780 "dns: failed to look up root DNS zones",
785 TYPESAFE_QSORT(res
->msgs
, res
->count
, dns_server_sort_zones
);
787 for (i
=0; i
< res
->count
; i
++) {
788 struct dns_server_zone
*z
;
790 z
= talloc_zero(dns
, struct dns_server_zone
);
794 z
->name
= ldb_msg_find_attr_as_string(res
->msgs
[i
], "name", NULL
);
795 z
->dn
= talloc_move(z
, &res
->msgs
[i
]->dn
);
797 DLIST_ADD_END(dns
->zones
, z
, NULL
);
800 status
= dns_startup_interfaces(dns
, task
->lp_ctx
, ifaces
);
801 if (!NT_STATUS_IS_OK(status
)) {
802 task_server_terminate(task
, "dns failed to setup interfaces", true);
807 NTSTATUS
server_service_dns_init(void)
809 return register_server_service("dns", dns_task_init
);