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"
46 NTSTATUS
server_service_dns_init(void);
48 /* hold information about one dns socket */
50 struct dns_server
*dns
;
51 struct tsocket_address
*local_address
;
54 struct dns_udp_socket
{
55 struct dns_socket
*dns_socket
;
56 struct tdgram_context
*dgram
;
57 struct tevent_queue
*send_queue
;
61 state of an open tcp connection
63 struct dns_tcp_connection
{
64 /* stream connection we belong to */
65 struct stream_connection
*conn
;
67 /* the dns_server the connection belongs to */
68 struct dns_socket
*dns_socket
;
70 struct tstream_context
*tstream
;
72 struct tevent_queue
*send_queue
;
75 static void dns_tcp_terminate_connection(struct dns_tcp_connection
*dnsconn
, const char *reason
)
77 stream_terminate_connection(dnsconn
->conn
, reason
);
80 static void dns_tcp_recv(struct stream_connection
*conn
, uint16_t flags
)
82 struct dns_tcp_connection
*dnsconn
= talloc_get_type(conn
->private_data
,
83 struct dns_tcp_connection
);
84 /* this should never be triggered! */
85 dns_tcp_terminate_connection(dnsconn
, "dns_tcp_recv: called");
88 static void dns_tcp_send(struct stream_connection
*conn
, uint16_t flags
)
90 struct dns_tcp_connection
*dnsconn
= talloc_get_type(conn
->private_data
,
91 struct dns_tcp_connection
);
92 /* this should never be triggered! */
93 dns_tcp_terminate_connection(dnsconn
, "dns_tcp_send: called");
96 static NTSTATUS
dns_process(struct dns_server
*dns
,
101 enum ndr_err_code ndr_err
;
103 uint16_t dns_err
= DNS_RCODE_OK
;
104 struct dns_request_state
*state
;
105 struct dns_name_packet
*in_packet
;
106 struct dns_name_packet
*out_packet
;
107 struct dns_res_rec
*answers
= NULL
, *nsrecs
= NULL
, *additional
= NULL
;
108 uint16_t num_answers
= 0 , num_nsrecs
= 0, num_additional
= 0;
110 if (in
->length
< 12) {
111 return NT_STATUS_INVALID_PARAMETER
;
114 state
= talloc_zero(mem_ctx
, struct dns_request_state
);
116 in_packet
= talloc_zero(state
, struct dns_name_packet
);
117 /* TODO: We don't really need an out_packet. */
118 out_packet
= talloc_zero(state
, struct dns_name_packet
);
120 if (in_packet
== NULL
) return NT_STATUS_NO_MEMORY
;
121 if (out_packet
== NULL
) return NT_STATUS_NO_MEMORY
;
123 dump_data(8, in
->data
, in
->length
);
125 ndr_err
= ndr_pull_struct_blob(in
, in_packet
, in_packet
,
126 (ndr_pull_flags_fn_t
)ndr_pull_dns_name_packet
);
127 if (!NDR_ERR_CODE_IS_SUCCESS(ndr_err
)) {
128 TALLOC_FREE(in_packet
);
129 DEBUG(0, ("Failed to parse packet %d!\n", ndr_err
));
130 dns_err
= DNS_RCODE_FORMERR
;
134 NDR_PRINT_DEBUG(dns_name_packet
, in_packet
);
136 *out_packet
= *in_packet
;
137 state
->flags
|= in_packet
->operation
| DNS_FLAG_REPLY
;
139 if (lpcfg_dns_recursive_queries(dns
->task
->lp_ctx
)) {
140 state
->flags
|= DNS_FLAG_RECURSION_AVAIL
;
143 switch (in_packet
->operation
& DNS_OPCODE
) {
144 case DNS_OPCODE_QUERY
:
146 ret
= dns_server_process_query(dns
, state
,
147 out_packet
, in_packet
,
148 &answers
, &num_answers
,
149 &nsrecs
, &num_nsrecs
,
150 &additional
, &num_additional
);
153 case DNS_OPCODE_UPDATE
:
154 ret
= dns_server_process_update(dns
, state
,
155 out_packet
, in_packet
,
156 &answers
, &num_answers
,
157 &nsrecs
, &num_nsrecs
,
158 &additional
, &num_additional
);
161 ret
= WERR_DNS_ERROR_RCODE_NOT_IMPLEMENTED
;
165 if (W_ERROR_IS_OK(ret
)) {
166 out_packet
->ancount
= num_answers
;
167 out_packet
->answers
= answers
;
169 out_packet
->nscount
= num_nsrecs
;
170 out_packet
->nsrecs
= nsrecs
;
172 out_packet
->arcount
= num_additional
;
173 out_packet
->additional
= additional
;
175 out_packet
->operation
|= werr_to_dns_err(ret
);
178 out_packet
->operation
|= state
->flags
;
181 NDR_PRINT_DEBUG(dns_name_packet
, out_packet
);
183 ndr_err
= ndr_push_struct_blob(out
, out_packet
, out_packet
,
184 (ndr_push_flags_fn_t
)ndr_push_dns_name_packet
);
185 if (!NDR_ERR_CODE_IS_SUCCESS(ndr_err
)) {
186 TALLOC_FREE(in_packet
);
187 TALLOC_FREE(out_packet
);
188 DEBUG(0, ("Failed to push packet %d!\n", ndr_err
));
189 dns_err
= DNS_RCODE_SERVFAIL
;
193 dump_data(8, out
->data
, out
->length
);
198 out
->data
[2] |= 0x80; /* Toggle DNS_FLAG_REPLY */
199 out
->data
[3] |= dns_err
;
203 struct dns_tcp_call
{
204 struct dns_tcp_connection
*dns_conn
;
208 struct iovec out_iov
[2];
211 static void dns_tcp_call_writev_done(struct tevent_req
*subreq
);
213 static void dns_tcp_call_loop(struct tevent_req
*subreq
)
215 struct dns_tcp_connection
*dns_conn
= tevent_req_callback_data(subreq
,
216 struct dns_tcp_connection
);
217 struct dns_tcp_call
*call
;
220 call
= talloc(dns_conn
, struct dns_tcp_call
);
222 dns_tcp_terminate_connection(dns_conn
, "dns_tcp_call_loop: "
223 "no memory for dns_tcp_call");
226 call
->dns_conn
= dns_conn
;
228 status
= tstream_read_pdu_blob_recv(subreq
,
232 if (!NT_STATUS_IS_OK(status
)) {
235 reason
= talloc_asprintf(call
, "dns_tcp_call_loop: "
236 "tstream_read_pdu_blob_recv() - %s",
239 reason
= nt_errstr(status
);
242 dns_tcp_terminate_connection(dns_conn
, reason
);
246 DEBUG(10,("Received DNS TCP packet of length %lu from %s\n",
247 (long) call
->in
.length
,
248 tsocket_address_string(dns_conn
->conn
->remote_address
, call
)));
250 /* skip length header */
252 call
->in
.length
-= 2;
255 status
= dns_process(dns_conn
->dns_socket
->dns
, call
, &call
->in
, &call
->out
);
256 if (!NT_STATUS_IS_OK(status
)) {
257 DEBUG(0, ("dns_process returned %s\n", nt_errstr(status
)));
258 dns_tcp_terminate_connection(dns_conn
,
259 "dns_tcp_call_loop: process function failed");
263 /* First add the length of the out buffer */
264 RSSVAL(call
->out_hdr
, 0, call
->out
.length
);
265 call
->out_iov
[0].iov_base
= (char *) call
->out_hdr
;
266 call
->out_iov
[0].iov_len
= 2;
268 call
->out_iov
[1].iov_base
= (char *) call
->out
.data
;
269 call
->out_iov
[1].iov_len
= call
->out
.length
;
271 subreq
= tstream_writev_queue_send(call
,
272 dns_conn
->conn
->event
.ctx
,
274 dns_conn
->send_queue
,
276 if (subreq
== NULL
) {
277 dns_tcp_terminate_connection(dns_conn
, "dns_tcp_call_loop: "
278 "no memory for tstream_writev_queue_send");
281 tevent_req_set_callback(subreq
, dns_tcp_call_writev_done
, call
);
284 * The dns tcp pdu's has the length as 2 byte (initial_read_size),
285 * packet_full_request_u16 provides the pdu length then.
287 subreq
= tstream_read_pdu_blob_send(dns_conn
,
288 dns_conn
->conn
->event
.ctx
,
290 2, /* initial_read_size */
291 packet_full_request_u16
,
293 if (subreq
== NULL
) {
294 dns_tcp_terminate_connection(dns_conn
, "dns_tcp_call_loop: "
295 "no memory for tstream_read_pdu_blob_send");
298 tevent_req_set_callback(subreq
, dns_tcp_call_loop
, dns_conn
);
301 static void dns_tcp_call_writev_done(struct tevent_req
*subreq
)
303 struct dns_tcp_call
*call
= tevent_req_callback_data(subreq
,
304 struct dns_tcp_call
);
308 rc
= tstream_writev_queue_recv(subreq
, &sys_errno
);
313 reason
= talloc_asprintf(call
, "dns_tcp_call_writev_done: "
314 "tstream_writev_queue_recv() - %d:%s",
315 sys_errno
, strerror(sys_errno
));
317 reason
= "dns_tcp_call_writev_done: tstream_writev_queue_recv() failed";
320 dns_tcp_terminate_connection(call
->dns_conn
, reason
);
324 /* We don't care about errors */
330 called when we get a new connection
332 static void dns_tcp_accept(struct stream_connection
*conn
)
334 struct dns_socket
*dns_socket
;
335 struct dns_tcp_connection
*dns_conn
;
336 struct tevent_req
*subreq
;
339 dns_conn
= talloc_zero(conn
, struct dns_tcp_connection
);
340 if (dns_conn
== NULL
) {
341 stream_terminate_connection(conn
,
342 "dns_tcp_accept: out of memory");
346 dns_conn
->send_queue
= tevent_queue_create(conn
, "dns_tcp_accept");
347 if (dns_conn
->send_queue
== NULL
) {
348 stream_terminate_connection(conn
,
349 "dns_tcp_accept: out of memory");
353 dns_socket
= talloc_get_type(conn
->private_data
, struct dns_socket
);
355 TALLOC_FREE(conn
->event
.fde
);
357 rc
= tstream_bsd_existing_socket(dns_conn
,
358 socket_get_fd(conn
->socket
),
361 stream_terminate_connection(conn
,
362 "dns_tcp_accept: out of memory");
366 dns_conn
->conn
= conn
;
367 dns_conn
->dns_socket
= dns_socket
;
368 conn
->private_data
= dns_conn
;
371 * The dns tcp pdu's has the length as 2 byte (initial_read_size),
372 * packet_full_request_u16 provides the pdu length then.
374 subreq
= tstream_read_pdu_blob_send(dns_conn
,
375 dns_conn
->conn
->event
.ctx
,
377 2, /* initial_read_size */
378 packet_full_request_u16
,
380 if (subreq
== NULL
) {
381 dns_tcp_terminate_connection(dns_conn
, "dns_tcp_accept: "
382 "no memory for tstream_read_pdu_blob_send");
385 tevent_req_set_callback(subreq
, dns_tcp_call_loop
, dns_conn
);
388 static const struct stream_server_ops dns_tcp_stream_ops
= {
390 .accept_connection
= dns_tcp_accept
,
391 .recv_handler
= dns_tcp_recv
,
392 .send_handler
= dns_tcp_send
395 struct dns_udp_call
{
396 struct tsocket_address
*src
;
401 static void dns_udp_call_sendto_done(struct tevent_req
*subreq
);
403 static void dns_udp_call_loop(struct tevent_req
*subreq
)
405 struct dns_udp_socket
*sock
= tevent_req_callback_data(subreq
,
406 struct dns_udp_socket
);
407 struct dns_udp_call
*call
;
413 call
= talloc(sock
, struct dns_udp_call
);
419 len
= tdgram_recvfrom_recv(subreq
, &sys_errno
,
420 call
, &buf
, &call
->src
);
428 call
->in
.length
= len
;
430 DEBUG(10,("Received DNS UDP packet of length %lu from %s\n",
431 (long)call
->in
.length
,
432 tsocket_address_string(call
->src
, call
)));
434 /* Call dns_process */
435 status
= dns_process(sock
->dns_socket
->dns
, call
, &call
->in
, &call
->out
);
436 if (!NT_STATUS_IS_OK(status
)) {
438 DEBUG(0, ("dns_process returned %s\n", nt_errstr(status
)));
442 subreq
= tdgram_sendto_queue_send(call
,
443 sock
->dns_socket
->dns
->task
->event_ctx
,
449 if (subreq
== NULL
) {
453 tevent_req_set_callback(subreq
, dns_udp_call_sendto_done
, call
);
456 subreq
= tdgram_recvfrom_send(sock
,
457 sock
->dns_socket
->dns
->task
->event_ctx
,
459 if (subreq
== NULL
) {
460 task_server_terminate(sock
->dns_socket
->dns
->task
,
461 "no memory for tdgram_recvfrom_send",
465 tevent_req_set_callback(subreq
, dns_udp_call_loop
, sock
);
468 static void dns_udp_call_sendto_done(struct tevent_req
*subreq
)
470 struct dns_udp_call
*call
= tevent_req_callback_data(subreq
,
471 struct dns_udp_call
);
475 ret
= tdgram_sendto_queue_recv(subreq
, &sys_errno
);
477 /* We don't care about errors */
483 start listening on the given address
485 static NTSTATUS
dns_add_socket(struct dns_server
*dns
,
486 const struct model_ops
*model_ops
,
491 struct dns_socket
*dns_socket
;
492 struct dns_udp_socket
*dns_udp_socket
;
493 struct tevent_req
*udpsubreq
;
497 dns_socket
= talloc(dns
, struct dns_socket
);
498 NT_STATUS_HAVE_NO_MEMORY(dns_socket
);
500 dns_socket
->dns
= dns
;
502 ret
= tsocket_address_inet_from_strings(dns_socket
, "ip",
504 &dns_socket
->local_address
);
506 status
= map_nt_error_from_unix_common(errno
);
510 status
= stream_setup_socket(dns
->task
,
511 dns
->task
->event_ctx
,
515 "ip", address
, &port
,
516 lpcfg_socket_options(dns
->task
->lp_ctx
),
518 if (!NT_STATUS_IS_OK(status
)) {
519 DEBUG(0,("Failed to bind to %s:%u TCP - %s\n",
520 address
, port
, nt_errstr(status
)));
521 talloc_free(dns_socket
);
525 dns_udp_socket
= talloc(dns_socket
, struct dns_udp_socket
);
526 NT_STATUS_HAVE_NO_MEMORY(dns_udp_socket
);
528 dns_udp_socket
->dns_socket
= dns_socket
;
530 ret
= tdgram_inet_udp_socket(dns_socket
->local_address
,
533 &dns_udp_socket
->dgram
);
535 status
= map_nt_error_from_unix_common(errno
);
536 DEBUG(0,("Failed to bind to %s:%u UDP - %s\n",
537 address
, port
, nt_errstr(status
)));
541 dns_udp_socket
->send_queue
= tevent_queue_create(dns_udp_socket
,
542 "dns_udp_send_queue");
543 NT_STATUS_HAVE_NO_MEMORY(dns_udp_socket
->send_queue
);
545 udpsubreq
= tdgram_recvfrom_send(dns_udp_socket
,
546 dns
->task
->event_ctx
,
547 dns_udp_socket
->dgram
);
548 NT_STATUS_HAVE_NO_MEMORY(udpsubreq
);
549 tevent_req_set_callback(udpsubreq
, dns_udp_call_loop
, dns_udp_socket
);
555 setup our listening sockets on the configured network interfaces
557 static NTSTATUS
dns_startup_interfaces(struct dns_server
*dns
, struct loadparm_context
*lp_ctx
,
558 struct interface
*ifaces
)
560 const struct model_ops
*model_ops
;
562 TALLOC_CTX
*tmp_ctx
= talloc_new(dns
);
566 /* within the dns task we want to be a single process, so
567 ask for the single process model ops and pass these to the
568 stream_setup_socket() call. */
569 model_ops
= process_model_startup("single");
571 DEBUG(0,("Can't find 'single' process model_ops\n"));
572 return NT_STATUS_INTERNAL_ERROR
;
575 num_interfaces
= iface_list_count(ifaces
);
577 for (i
=0; i
<num_interfaces
; i
++) {
578 const char *address
= talloc_strdup(tmp_ctx
, iface_list_n_ip(ifaces
, i
));
580 status
= dns_add_socket(dns
, model_ops
, "dns", address
, DNS_SERVICE_PORT
);
581 NT_STATUS_NOT_OK_RETURN(status
);
584 talloc_free(tmp_ctx
);
589 static int dns_server_sort_zones(struct ldb_message
**m1
, struct ldb_message
**m2
)
594 n1
= ldb_msg_find_attr_as_string(*m1
, "name", NULL
);
595 n2
= ldb_msg_find_attr_as_string(*m2
, "name", NULL
);
600 /* If the string lengths are not equal just sort by length */
602 /* If m1 is the larger zone name, return it first */
606 /*TODO: We need to compare DNs here, we want the DomainDNSZones first */
610 static void dns_task_init(struct task_server
*task
)
612 struct dns_server
*dns
;
614 struct interface
*ifaces
;
616 struct ldb_result
*res
;
617 static const char * const attrs
[] = { "name", NULL
};
620 switch (lpcfg_server_role(task
->lp_ctx
)) {
621 case ROLE_STANDALONE
:
622 task_server_terminate(task
, "dns: no DNS required in standalone configuration", false);
624 case ROLE_DOMAIN_MEMBER
:
625 task_server_terminate(task
, "dns: no DNS required in member server configuration", false);
627 case ROLE_DOMAIN_CONTROLLER
:
628 /* Yes, we want a DNS */
632 load_interface_list(task
, task
->lp_ctx
, &ifaces
);
634 if (iface_list_count(ifaces
) == 0) {
635 task_server_terminate(task
, "dns: no network interfaces configured", false);
639 task_server_set_title(task
, "task[dns]");
641 dns
= talloc_zero(task
, struct dns_server
);
643 task_server_terminate(task
, "dns: out of memory", true);
649 dns
->samdb
= samdb_connect(dns
, dns
->task
->event_ctx
, dns
->task
->lp_ctx
,
650 system_session(dns
->task
->lp_ctx
), 0);
652 task_server_terminate(task
, "dns: samdb_connect failed", true);
656 // TODO: this search does not work against windows
657 ret
= dsdb_search(dns
->samdb
, dns
, &res
, NULL
, LDB_SCOPE_SUBTREE
,
658 attrs
, DSDB_SEARCH_SEARCH_ALL_PARTITIONS
, "(objectClass=dnsZone)");
659 if (ret
!= LDB_SUCCESS
) {
660 task_server_terminate(task
,
661 "dns: failed to look up root DNS zones",
666 TYPESAFE_QSORT(res
->msgs
, res
->count
, dns_server_sort_zones
);
668 for (i
=0; i
< res
->count
; i
++) {
669 struct dns_server_zone
*z
;
671 z
= talloc_zero(dns
, struct dns_server_zone
);
675 z
->name
= ldb_msg_find_attr_as_string(res
->msgs
[i
], "name", NULL
);
676 z
->dn
= talloc_move(z
, &res
->msgs
[i
]->dn
);
678 DLIST_ADD_END(dns
->zones
, z
, NULL
);
681 status
= dns_startup_interfaces(dns
, task
->lp_ctx
, ifaces
);
682 if (!NT_STATUS_IS_OK(status
)) {
683 task_server_terminate(task
, "dns failed to setup interfaces", true);
688 NTSTATUS
server_service_dns_init(void)
690 return register_server_service("dns", dns_task_init
);