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_server *dns;
102 struct dns_name_packet in_packet;
103 struct dns_request_state state;
105 struct dns_name_packet out_packet;
109 static void dns_process_done(struct tevent_req *subreq);
111 static struct tevent_req *dns_process_send(TALLOC_CTX *mem_ctx,
112 struct tevent_context *ev,
113 struct dns_server *dns,
116 struct tevent_req *req, *subreq;
117 struct dns_process_state *state;
118 enum ndr_err_code ndr_err;
121 req = tevent_req_create(mem_ctx, &state, struct dns_process_state);
129 if (in->length < 12) {
130 tevent_req_werror(req, WERR_INVALID_PARAM);
131 return tevent_req_post(req, ev);
133 dump_data(8, in->data, in->length);
135 ndr_err = ndr_pull_struct_blob(
136 in, state, &state->in_packet,
137 (ndr_pull_flags_fn_t)ndr_pull_dns_name_packet);
139 if (!NDR_ERR_CODE_IS_SUCCESS(ndr_err)) {
140 state->dns_err = DNS_RCODE_FORMERR;
141 tevent_req_done(req);
142 return tevent_req_post(req, ev);
145 NDR_PRINT_DEBUG(dns_name_packet, &state->in_packet);
148 ret = dns_verify_tsig(dns, state, &state->state, &state->in_packet, in);
149 if (!W_ERROR_IS_OK(ret)) {
150 DEBUG(0, ("Bailing out early!\n"));
151 state->dns_err = werr_to_dns_err(ret);
152 tevent_req_done(req);
153 return tevent_req_post(req, ev);
156 state->state.flags = state->in_packet.operation;
157 state->state.flags |= DNS_FLAG_REPLY;
159 if (lpcfg_dns_recursive_queries(dns->task->lp_ctx)) {
160 state->state.flags |= DNS_FLAG_RECURSION_AVAIL;
163 state->out_packet = state->in_packet;
165 switch (state->in_packet.operation & DNS_OPCODE) {
166 case DNS_OPCODE_QUERY:
167 subreq = dns_server_process_query_send(
168 state, ev, dns, &state->state, &state->in_packet);
169 if (tevent_req_nomem(subreq, req)) {
170 return tevent_req_post(req, ev);
172 tevent_req_set_callback(subreq, dns_process_done, req);
174 case DNS_OPCODE_UPDATE:
175 ret = dns_server_process_update(
176 dns, &state->state, state, &state->in_packet,
177 &state->out_packet.answers, &state->out_packet.ancount,
178 &state->out_packet.nsrecs, &state->out_packet.nscount,
179 &state->out_packet.additional,
180 &state->out_packet.arcount);
183 ret = WERR_DNS_ERROR_RCODE_NOT_IMPLEMENTED;
185 if (!W_ERROR_IS_OK(ret)) {
186 state->dns_err = werr_to_dns_err(ret);
188 tevent_req_done(req);
189 return tevent_req_post(req, ev);
192 static void dns_process_done(struct tevent_req *subreq)
194 struct tevent_req *req = tevent_req_callback_data(
195 subreq, struct tevent_req);
196 struct dns_process_state *state = tevent_req_data(
197 req, struct dns_process_state);
200 ret = dns_server_process_query_recv(
202 &state->out_packet.answers, &state->out_packet.ancount,
203 &state->out_packet.nsrecs, &state->out_packet.nscount,
204 &state->out_packet.additional, &state->out_packet.arcount);
207 if (!W_ERROR_IS_OK(ret)) {
208 state->dns_err = werr_to_dns_err(ret);
210 tevent_req_done(req);
213 static WERROR dns_process_recv(struct tevent_req *req, TALLOC_CTX *mem_ctx,
216 struct dns_process_state *state = tevent_req_data(
217 req, struct dns_process_state);
218 enum ndr_err_code ndr_err;
221 if (tevent_req_is_werror(req, &ret)) {
224 if (state->dns_err != DNS_RCODE_OK) {
227 state->out_packet.operation |= state->state.flags;
229 if (state->state.sign) {
230 DEBUG(0, ("Signing\n"));
231 ret = dns_sign_tsig(state->dns, mem_ctx, &state->state,
232 &state->out_packet, 0);
233 if (!W_ERROR_IS_OK(ret)) {
234 state->dns_err = DNS_RCODE_SERVFAIL;
239 //NDR_PRINT_DEBUG(dns_name_packet, &state->out_packet);
241 ndr_err = ndr_push_struct_blob(
242 out, mem_ctx, &state->out_packet,
243 (ndr_push_flags_fn_t)ndr_push_dns_name_packet);
244 if (!NDR_ERR_CODE_IS_SUCCESS(ndr_err)) {
245 DEBUG(1, ("Failed to push packet: %s!\n",
246 ndr_errstr(ndr_err)));
247 state->dns_err = DNS_RCODE_SERVFAIL;
253 *out = data_blob_talloc(mem_ctx, state->in->data, state->in->length);
254 if (out->data == NULL) {
257 out->data[2] |= 0x80; /* Toggle DNS_FLAG_REPLY */
258 out->data[3] |= state->dns_err;
262 struct dns_tcp_call {
263 struct dns_tcp_connection *dns_conn;
267 struct iovec out_iov[2];
270 static void dns_tcp_call_process_done(struct tevent_req *subreq);
271 static void dns_tcp_call_writev_done(struct tevent_req *subreq);
273 static void dns_tcp_call_loop(struct tevent_req *subreq)
275 struct dns_tcp_connection *dns_conn = tevent_req_callback_data(subreq,
276 struct dns_tcp_connection);
277 struct dns_server *dns = dns_conn->dns_socket->dns;
278 struct dns_tcp_call *call;
281 call = talloc(dns_conn, struct dns_tcp_call);
283 dns_tcp_terminate_connection(dns_conn, "dns_tcp_call_loop: "
284 "no memory for dns_tcp_call");
287 call->dns_conn = dns_conn;
289 status = tstream_read_pdu_blob_recv(subreq,
293 if (!NT_STATUS_IS_OK(status)) {
296 reason = talloc_asprintf(call, "dns_tcp_call_loop: "
297 "tstream_read_pdu_blob_recv() - %s",
300 reason = nt_errstr(status);
303 dns_tcp_terminate_connection(dns_conn, reason);
307 DEBUG(10,("Received DNS TCP packet of length %lu from %s\n",
308 (long) call->in.length,
309 tsocket_address_string(dns_conn->conn->remote_address, call)));
311 /* skip length header */
313 call->in.length -= 2;
315 subreq = dns_process_send(call, dns->task->event_ctx, dns,
317 if (subreq == NULL) {
318 dns_tcp_terminate_connection(
319 dns_conn, "dns_tcp_call_loop: dns_process_send "
323 tevent_req_set_callback(subreq, dns_tcp_call_process_done, call);
326 * The dns tcp pdu's has the length as 2 byte (initial_read_size),
327 * packet_full_request_u16 provides the pdu length then.
329 subreq = tstream_read_pdu_blob_send(dns_conn,
330 dns_conn->conn->event.ctx,
332 2, /* initial_read_size */
333 packet_full_request_u16,
335 if (subreq == NULL) {
336 dns_tcp_terminate_connection(dns_conn, "dns_tcp_call_loop: "
337 "no memory for tstream_read_pdu_blob_send");
340 tevent_req_set_callback(subreq, dns_tcp_call_loop, dns_conn);
343 static void dns_tcp_call_process_done(struct tevent_req *subreq)
345 struct dns_tcp_call *call = tevent_req_callback_data(subreq,
346 struct dns_tcp_call);
347 struct dns_tcp_connection *dns_conn = call->dns_conn;
350 err = dns_process_recv(subreq, call, &call->out);
352 if (!W_ERROR_IS_OK(err)) {
353 DEBUG(1, ("dns_process returned %s\n", win_errstr(err)));
354 dns_tcp_terminate_connection(dns_conn,
355 "dns_tcp_call_loop: process function failed");
359 /* First add the length of the out buffer */
360 RSSVAL(call->out_hdr, 0, call->out.length);
361 call->out_iov[0].iov_base = (char *) call->out_hdr;
362 call->out_iov[0].iov_len = 2;
364 call->out_iov[1].iov_base = (char *) call->out.data;
365 call->out_iov[1].iov_len = call->out.length;
367 subreq = tstream_writev_queue_send(call,
368 dns_conn->conn->event.ctx,
370 dns_conn->send_queue,
372 if (subreq == NULL) {
373 dns_tcp_terminate_connection(dns_conn, "dns_tcp_call_loop: "
374 "no memory for tstream_writev_queue_send");
377 tevent_req_set_callback(subreq, dns_tcp_call_writev_done, call);
380 static void dns_tcp_call_writev_done(struct tevent_req *subreq)
382 struct dns_tcp_call *call = tevent_req_callback_data(subreq,
383 struct dns_tcp_call);
387 rc = tstream_writev_queue_recv(subreq, &sys_errno);
392 reason = talloc_asprintf(call, "dns_tcp_call_writev_done: "
393 "tstream_writev_queue_recv() - %d:%s",
394 sys_errno, strerror(sys_errno));
396 reason = "dns_tcp_call_writev_done: tstream_writev_queue_recv() failed";
399 dns_tcp_terminate_connection(call->dns_conn, reason);
403 /* We don't care about errors */
409 called when we get a new connection
411 static void dns_tcp_accept(struct stream_connection *conn)
413 struct dns_socket *dns_socket;
414 struct dns_tcp_connection *dns_conn;
415 struct tevent_req *subreq;
418 dns_conn = talloc_zero(conn, struct dns_tcp_connection);
419 if (dns_conn == NULL) {
420 stream_terminate_connection(conn,
421 "dns_tcp_accept: out of memory");
425 dns_conn->send_queue = tevent_queue_create(conn, "dns_tcp_accept");
426 if (dns_conn->send_queue == NULL) {
427 stream_terminate_connection(conn,
428 "dns_tcp_accept: out of memory");
432 dns_socket = talloc_get_type(conn->private_data, struct dns_socket);
434 TALLOC_FREE(conn->event.fde);
436 rc = tstream_bsd_existing_socket(dns_conn,
437 socket_get_fd(conn->socket),
440 stream_terminate_connection(conn,
441 "dns_tcp_accept: out of memory");
445 dns_conn->conn = conn;
446 dns_conn->dns_socket = dns_socket;
447 conn->private_data = dns_conn;
450 * The dns tcp pdu's has the length as 2 byte (initial_read_size),
451 * packet_full_request_u16 provides the pdu length then.
453 subreq = tstream_read_pdu_blob_send(dns_conn,
454 dns_conn->conn->event.ctx,
456 2, /* initial_read_size */
457 packet_full_request_u16,
459 if (subreq == NULL) {
460 dns_tcp_terminate_connection(dns_conn, "dns_tcp_accept: "
461 "no memory for tstream_read_pdu_blob_send");
464 tevent_req_set_callback(subreq, dns_tcp_call_loop, dns_conn);
467 static const struct stream_server_ops dns_tcp_stream_ops = {
469 .accept_connection = dns_tcp_accept,
470 .recv_handler = dns_tcp_recv,
471 .send_handler = dns_tcp_send
474 struct dns_udp_call {
475 struct dns_udp_socket *sock;
476 struct tsocket_address *src;
481 static void dns_udp_call_process_done(struct tevent_req *subreq);
482 static void dns_udp_call_sendto_done(struct tevent_req *subreq);
484 static void dns_udp_call_loop(struct tevent_req *subreq)
486 struct dns_udp_socket *sock = tevent_req_callback_data(subreq,
487 struct dns_udp_socket);
488 struct dns_server *dns = sock->dns_socket->dns;
489 struct dns_udp_call *call;
494 call = talloc(sock, struct dns_udp_call);
501 len = tdgram_recvfrom_recv(subreq, &sys_errno,
502 call, &buf, &call->src);
510 call->in.length = len;
512 DEBUG(10,("Received DNS UDP packet of length %lu from %s\n",
513 (long)call->in.length,
514 tsocket_address_string(call->src, call)));
516 subreq = dns_process_send(call, dns->task->event_ctx, dns,
518 if (subreq == NULL) {
522 tevent_req_set_callback(subreq, dns_udp_call_process_done, call);
525 subreq = tdgram_recvfrom_send(sock,
526 sock->dns_socket->dns->task->event_ctx,
528 if (subreq == NULL) {
529 task_server_terminate(sock->dns_socket->dns->task,
530 "no memory for tdgram_recvfrom_send",
534 tevent_req_set_callback(subreq, dns_udp_call_loop, sock);
537 static void dns_udp_call_process_done(struct tevent_req *subreq)
539 struct dns_udp_call *call = tevent_req_callback_data(
540 subreq, struct dns_udp_call);
541 struct dns_udp_socket *sock = call->sock;
542 struct dns_server *dns = sock->dns_socket->dns;
545 err = dns_process_recv(subreq, call, &call->out);
547 if (!W_ERROR_IS_OK(err)) {
548 DEBUG(1, ("dns_process returned %s\n", win_errstr(err)));
553 subreq = tdgram_sendto_queue_send(call,
554 dns->task->event_ctx,
560 if (subreq == NULL) {
564 tevent_req_set_callback(subreq, dns_udp_call_sendto_done, call);
567 static void dns_udp_call_sendto_done(struct tevent_req *subreq)
569 struct dns_udp_call *call = tevent_req_callback_data(subreq,
570 struct dns_udp_call);
574 ret = tdgram_sendto_queue_recv(subreq, &sys_errno);
576 /* We don't care about errors */
582 start listening on the given address
584 static NTSTATUS dns_add_socket(struct dns_server *dns,
585 const struct model_ops *model_ops,
590 struct dns_socket *dns_socket;
591 struct dns_udp_socket *dns_udp_socket;
592 struct tevent_req *udpsubreq;
596 dns_socket = talloc(dns, struct dns_socket);
597 NT_STATUS_HAVE_NO_MEMORY(dns_socket);
599 dns_socket->dns = dns;
601 ret = tsocket_address_inet_from_strings(dns_socket, "ip",
603 &dns_socket->local_address);
605 status = map_nt_error_from_unix_common(errno);
609 status = stream_setup_socket(dns->task,
610 dns->task->event_ctx,
614 "ip", address, &port,
615 lpcfg_socket_options(dns->task->lp_ctx),
617 if (!NT_STATUS_IS_OK(status)) {
618 DEBUG(0,("Failed to bind to %s:%u TCP - %s\n",
619 address, port, nt_errstr(status)));
620 talloc_free(dns_socket);
624 dns_udp_socket = talloc(dns_socket, struct dns_udp_socket);
625 NT_STATUS_HAVE_NO_MEMORY(dns_udp_socket);
627 dns_udp_socket->dns_socket = dns_socket;
629 ret = tdgram_inet_udp_socket(dns_socket->local_address,
632 &dns_udp_socket->dgram);
634 status = map_nt_error_from_unix_common(errno);
635 DEBUG(0,("Failed to bind to %s:%u UDP - %s\n",
636 address, port, nt_errstr(status)));
640 dns_udp_socket->send_queue = tevent_queue_create(dns_udp_socket,
641 "dns_udp_send_queue");
642 NT_STATUS_HAVE_NO_MEMORY(dns_udp_socket->send_queue);
644 udpsubreq = tdgram_recvfrom_send(dns_udp_socket,
645 dns->task->event_ctx,
646 dns_udp_socket->dgram);
647 NT_STATUS_HAVE_NO_MEMORY(udpsubreq);
648 tevent_req_set_callback(udpsubreq, dns_udp_call_loop, dns_udp_socket);
654 setup our listening sockets on the configured network interfaces
656 static NTSTATUS dns_startup_interfaces(struct dns_server *dns, struct loadparm_context *lp_ctx,
657 struct interface *ifaces)
659 const struct model_ops *model_ops;
661 TALLOC_CTX *tmp_ctx = talloc_new(dns);
665 /* within the dns task we want to be a single process, so
666 ask for the single process model ops and pass these to the
667 stream_setup_socket() call. */
668 model_ops = process_model_startup("single");
670 DEBUG(0,("Can't find 'single' process model_ops\n"));
671 return NT_STATUS_INTERNAL_ERROR;
674 num_interfaces = iface_list_count(ifaces);
676 for (i=0; i<num_interfaces; i++) {
677 const char *address = talloc_strdup(tmp_ctx, iface_list_n_ip(ifaces, i));
679 status = dns_add_socket(dns, model_ops, "dns", address, DNS_SERVICE_PORT);
680 NT_STATUS_NOT_OK_RETURN(status);
683 talloc_free(tmp_ctx);
688 static int dns_server_sort_zones(struct ldb_message **m1, struct ldb_message **m2)
693 n1 = ldb_msg_find_attr_as_string(*m1, "name", NULL);
694 n2 = ldb_msg_find_attr_as_string(*m2, "name", NULL);
699 /* If the string lengths are not equal just sort by length */
701 /* If m1 is the larger zone name, return it first */
705 /*TODO: We need to compare DNs here, we want the DomainDNSZones first */
709 static struct dns_server_tkey_store *tkey_store_init(TALLOC_CTX *mem_ctx,
712 struct dns_server_tkey_store *buffer = talloc_zero(mem_ctx,
713 struct dns_server_tkey_store);
715 if (buffer == NULL) {
720 buffer->next_idx = 0;
722 buffer->tkeys = talloc_zero_array(buffer, struct dns_server_tkey *, size);
723 if (buffer->tkeys == NULL) {
730 static void dns_task_init(struct task_server *task)
732 struct dns_server *dns;
734 struct interface *ifaces;
736 struct ldb_result *res;
737 static const char * const attrs[] = { "name", NULL};
740 switch (lpcfg_server_role(task->lp_ctx)) {
741 case ROLE_STANDALONE:
742 task_server_terminate(task, "dns: no DNS required in standalone configuration", false);
744 case ROLE_DOMAIN_MEMBER:
745 task_server_terminate(task, "dns: no DNS required in member server configuration", false);
747 case ROLE_ACTIVE_DIRECTORY_DC:
748 /* Yes, we want a DNS */
752 load_interface_list(task, task->lp_ctx, &ifaces);
754 if (iface_list_count(ifaces) == 0) {
755 task_server_terminate(task, "dns: no network interfaces configured", false);
759 task_server_set_title(task, "task[dns]");
761 dns = talloc_zero(task, struct dns_server);
763 task_server_terminate(task, "dns: out of memory", true);
769 dns->server_credentials = cli_credentials_init(dns);
770 if (!dns->server_credentials) {
771 task_server_terminate(task, "Failed to init server credentials\n", true);
775 cli_credentials_set_conf(dns->server_credentials, task->lp_ctx);
776 status = cli_credentials_set_machine_account(dns->server_credentials, task->lp_ctx);
777 if (!NT_STATUS_IS_OK(status)) {
778 task_server_terminate(task,
779 talloc_asprintf(task, "Failed to obtain server credentials, perhaps a standalone server?: %s\n",
785 dns->tkeys = tkey_store_init(dns, TKEY_BUFFER_SIZE);
787 task_server_terminate(task, "Failed to allocate tkey storage\n", true);
791 dns->samdb = samdb_connect(dns, dns->task->event_ctx, dns->task->lp_ctx,
792 system_session(dns->task->lp_ctx), 0);
794 task_server_terminate(task, "dns: samdb_connect failed", true);
798 // TODO: this search does not work against windows
799 ret = dsdb_search(dns->samdb, dns, &res, NULL, LDB_SCOPE_SUBTREE,
800 attrs, DSDB_SEARCH_SEARCH_ALL_PARTITIONS, "(objectClass=dnsZone)");
801 if (ret != LDB_SUCCESS) {
802 task_server_terminate(task,
803 "dns: failed to look up root DNS zones",
808 TYPESAFE_QSORT(res->msgs, res->count, dns_server_sort_zones);
810 for (i=0; i < res->count; i++) {
811 struct dns_server_zone *z;
813 z = talloc_zero(dns, struct dns_server_zone);
817 z->name = ldb_msg_find_attr_as_string(res->msgs[i], "name", NULL);
818 z->dn = talloc_move(z, &res->msgs[i]->dn);
820 DLIST_ADD_END(dns->zones, z, NULL);
823 status = dns_startup_interfaces(dns, task->lp_ctx, ifaces);
824 if (!NT_STATUS_IS_OK(status)) {
825 task_server_terminate(task, "dns failed to setup interfaces", true);
830 NTSTATUS server_service_dns_init(void)
832 return register_server_service("dns", dns_task_init);