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"
47 NTSTATUS server_service_dns_init(void);
49 /* hold information about one dns socket */
51 struct dns_server *dns;
52 struct tsocket_address *local_address;
55 struct dns_udp_socket {
56 struct dns_socket *dns_socket;
57 struct tdgram_context *dgram;
58 struct tevent_queue *send_queue;
62 state of an open tcp connection
64 struct dns_tcp_connection {
65 /* stream connection we belong to */
66 struct stream_connection *conn;
68 /* the dns_server the connection belongs to */
69 struct dns_socket *dns_socket;
71 struct tstream_context *tstream;
73 struct tevent_queue *send_queue;
76 static void dns_tcp_terminate_connection(struct dns_tcp_connection *dnsconn, const char *reason)
78 stream_terminate_connection(dnsconn->conn, reason);
81 static void dns_tcp_recv(struct stream_connection *conn, uint16_t flags)
83 struct dns_tcp_connection *dnsconn = talloc_get_type(conn->private_data,
84 struct dns_tcp_connection);
85 /* this should never be triggered! */
86 dns_tcp_terminate_connection(dnsconn, "dns_tcp_recv: called");
89 static void dns_tcp_send(struct stream_connection *conn, uint16_t flags)
91 struct dns_tcp_connection *dnsconn = talloc_get_type(conn->private_data,
92 struct dns_tcp_connection);
93 /* this should never be triggered! */
94 dns_tcp_terminate_connection(dnsconn, "dns_tcp_send: called");
97 struct dns_process_state {
99 struct dns_name_packet in_packet;
100 struct dns_request_state state;
102 struct dns_name_packet out_packet;
106 static void dns_process_done(struct tevent_req *subreq);
108 static struct tevent_req *dns_process_send(TALLOC_CTX *mem_ctx,
109 struct tevent_context *ev,
110 struct dns_server *dns,
113 struct tevent_req *req, *subreq;
114 struct dns_process_state *state;
115 enum ndr_err_code ndr_err;
118 req = tevent_req_create(mem_ctx, &state, struct dns_process_state);
124 if (in->length < 12) {
125 tevent_req_werror(req, WERR_INVALID_PARAM);
126 return tevent_req_post(req, ev);
128 dump_data(8, in->data, in->length);
130 ndr_err = ndr_pull_struct_blob(
131 in, state, &state->in_packet,
132 (ndr_pull_flags_fn_t)ndr_pull_dns_name_packet);
134 if (!NDR_ERR_CODE_IS_SUCCESS(ndr_err)) {
135 state->dns_err = DNS_RCODE_FORMERR;
136 tevent_req_done(req);
137 return tevent_req_post(req, ev);
140 NDR_PRINT_DEBUG(dns_name_packet, &state->in_packet);
143 state->state.flags = state->in_packet.operation;
144 state->state.flags |= DNS_FLAG_REPLY;
146 if (lpcfg_dns_recursive_queries(dns->task->lp_ctx)) {
147 state->state.flags |= DNS_FLAG_RECURSION_AVAIL;
150 state->out_packet = state->in_packet;
152 switch (state->in_packet.operation & DNS_OPCODE) {
153 case DNS_OPCODE_QUERY:
154 subreq = dns_server_process_query_send(
155 state, ev, dns, &state->state, &state->in_packet);
156 if (tevent_req_nomem(subreq, req)) {
157 return tevent_req_post(req, ev);
159 tevent_req_set_callback(subreq, dns_process_done, req);
161 case DNS_OPCODE_UPDATE:
162 ret = dns_server_process_update(
163 dns, &state->state, state, &state->in_packet,
164 &state->out_packet.answers, &state->out_packet.ancount,
165 &state->out_packet.nsrecs, &state->out_packet.nscount,
166 &state->out_packet.additional,
167 &state->out_packet.arcount);
170 ret = WERR_DNS_ERROR_RCODE_NOT_IMPLEMENTED;
172 if (!W_ERROR_IS_OK(ret)) {
173 state->dns_err = werr_to_dns_err(ret);
175 tevent_req_done(req);
176 return tevent_req_post(req, ev);
179 static void dns_process_done(struct tevent_req *subreq)
181 struct tevent_req *req = tevent_req_callback_data(
182 subreq, struct tevent_req);
183 struct dns_process_state *state = tevent_req_data(
184 req, struct dns_process_state);
187 ret = dns_server_process_query_recv(
189 &state->out_packet.answers, &state->out_packet.ancount,
190 &state->out_packet.nsrecs, &state->out_packet.nscount,
191 &state->out_packet.additional, &state->out_packet.arcount);
194 if (!W_ERROR_IS_OK(ret)) {
195 state->dns_err = werr_to_dns_err(ret);
197 tevent_req_done(req);
200 static WERROR dns_process_recv(struct tevent_req *req, TALLOC_CTX *mem_ctx,
203 struct dns_process_state *state = tevent_req_data(
204 req, struct dns_process_state);
205 enum ndr_err_code ndr_err;
208 if (tevent_req_is_werror(req, &ret)) {
211 if (state->dns_err != DNS_RCODE_OK) {
214 state->out_packet.operation |= state->state.flags;
216 ndr_err = ndr_push_struct_blob(
217 out, mem_ctx, &state->out_packet,
218 (ndr_push_flags_fn_t)ndr_push_dns_name_packet);
219 if (!NDR_ERR_CODE_IS_SUCCESS(ndr_err)) {
220 DEBUG(1, ("Failed to push packet: %s!\n",
221 ndr_errstr(ndr_err)));
222 state->dns_err = DNS_RCODE_SERVFAIL;
228 *out = data_blob_talloc(mem_ctx, state->in->data, state->in->length);
229 if (out->data == NULL) {
232 out->data[2] |= 0x80; /* Toggle DNS_FLAG_REPLY */
233 out->data[3] |= state->dns_err;
237 static WERROR dns_process(struct dns_server *dns, TALLOC_CTX *mem_ctx,
238 DATA_BLOB *in, DATA_BLOB *out)
240 struct tevent_context *ev;
241 struct tevent_req *req;
242 WERROR err = WERR_NOMEM;
244 ev = tevent_context_init(talloc_tos());
248 req = dns_process_send(ev, ev, dns, in);
252 if (!tevent_req_poll_werror(req, ev, &err)) {
255 err = dns_process_recv(req, mem_ctx, out);
261 struct dns_tcp_call {
262 struct dns_tcp_connection *dns_conn;
266 struct iovec out_iov[2];
269 static void dns_tcp_call_writev_done(struct tevent_req *subreq);
271 static void dns_tcp_call_loop(struct tevent_req *subreq)
273 struct dns_tcp_connection *dns_conn = tevent_req_callback_data(subreq,
274 struct dns_tcp_connection);
275 struct dns_tcp_call *call;
279 call = talloc(dns_conn, struct dns_tcp_call);
281 dns_tcp_terminate_connection(dns_conn, "dns_tcp_call_loop: "
282 "no memory for dns_tcp_call");
285 call->dns_conn = dns_conn;
287 status = tstream_read_pdu_blob_recv(subreq,
291 if (!NT_STATUS_IS_OK(status)) {
294 reason = talloc_asprintf(call, "dns_tcp_call_loop: "
295 "tstream_read_pdu_blob_recv() - %s",
298 reason = nt_errstr(status);
301 dns_tcp_terminate_connection(dns_conn, reason);
305 DEBUG(10,("Received DNS TCP packet of length %lu from %s\n",
306 (long) call->in.length,
307 tsocket_address_string(dns_conn->conn->remote_address, call)));
309 /* skip length header */
311 call->in.length -= 2;
314 err = dns_process(dns_conn->dns_socket->dns, call, &call->in,
316 if (!W_ERROR_IS_OK(err)) {
317 DEBUG(1, ("dns_process returned %s\n", win_errstr(err)));
318 dns_tcp_terminate_connection(dns_conn,
319 "dns_tcp_call_loop: process function failed");
323 /* First add the length of the out buffer */
324 RSSVAL(call->out_hdr, 0, call->out.length);
325 call->out_iov[0].iov_base = (char *) call->out_hdr;
326 call->out_iov[0].iov_len = 2;
328 call->out_iov[1].iov_base = (char *) call->out.data;
329 call->out_iov[1].iov_len = call->out.length;
331 subreq = tstream_writev_queue_send(call,
332 dns_conn->conn->event.ctx,
334 dns_conn->send_queue,
336 if (subreq == NULL) {
337 dns_tcp_terminate_connection(dns_conn, "dns_tcp_call_loop: "
338 "no memory for tstream_writev_queue_send");
341 tevent_req_set_callback(subreq, dns_tcp_call_writev_done, call);
344 * The dns tcp pdu's has the length as 2 byte (initial_read_size),
345 * packet_full_request_u16 provides the pdu length then.
347 subreq = tstream_read_pdu_blob_send(dns_conn,
348 dns_conn->conn->event.ctx,
350 2, /* initial_read_size */
351 packet_full_request_u16,
353 if (subreq == NULL) {
354 dns_tcp_terminate_connection(dns_conn, "dns_tcp_call_loop: "
355 "no memory for tstream_read_pdu_blob_send");
358 tevent_req_set_callback(subreq, dns_tcp_call_loop, dns_conn);
361 static void dns_tcp_call_writev_done(struct tevent_req *subreq)
363 struct dns_tcp_call *call = tevent_req_callback_data(subreq,
364 struct dns_tcp_call);
368 rc = tstream_writev_queue_recv(subreq, &sys_errno);
373 reason = talloc_asprintf(call, "dns_tcp_call_writev_done: "
374 "tstream_writev_queue_recv() - %d:%s",
375 sys_errno, strerror(sys_errno));
377 reason = "dns_tcp_call_writev_done: tstream_writev_queue_recv() failed";
380 dns_tcp_terminate_connection(call->dns_conn, reason);
384 /* We don't care about errors */
390 called when we get a new connection
392 static void dns_tcp_accept(struct stream_connection *conn)
394 struct dns_socket *dns_socket;
395 struct dns_tcp_connection *dns_conn;
396 struct tevent_req *subreq;
399 dns_conn = talloc_zero(conn, struct dns_tcp_connection);
400 if (dns_conn == NULL) {
401 stream_terminate_connection(conn,
402 "dns_tcp_accept: out of memory");
406 dns_conn->send_queue = tevent_queue_create(conn, "dns_tcp_accept");
407 if (dns_conn->send_queue == NULL) {
408 stream_terminate_connection(conn,
409 "dns_tcp_accept: out of memory");
413 dns_socket = talloc_get_type(conn->private_data, struct dns_socket);
415 TALLOC_FREE(conn->event.fde);
417 rc = tstream_bsd_existing_socket(dns_conn,
418 socket_get_fd(conn->socket),
421 stream_terminate_connection(conn,
422 "dns_tcp_accept: out of memory");
426 dns_conn->conn = conn;
427 dns_conn->dns_socket = dns_socket;
428 conn->private_data = dns_conn;
431 * The dns tcp pdu's has the length as 2 byte (initial_read_size),
432 * packet_full_request_u16 provides the pdu length then.
434 subreq = tstream_read_pdu_blob_send(dns_conn,
435 dns_conn->conn->event.ctx,
437 2, /* initial_read_size */
438 packet_full_request_u16,
440 if (subreq == NULL) {
441 dns_tcp_terminate_connection(dns_conn, "dns_tcp_accept: "
442 "no memory for tstream_read_pdu_blob_send");
445 tevent_req_set_callback(subreq, dns_tcp_call_loop, dns_conn);
448 static const struct stream_server_ops dns_tcp_stream_ops = {
450 .accept_connection = dns_tcp_accept,
451 .recv_handler = dns_tcp_recv,
452 .send_handler = dns_tcp_send
455 struct dns_udp_call {
456 struct tsocket_address *src;
461 static void dns_udp_call_sendto_done(struct tevent_req *subreq);
463 static void dns_udp_call_loop(struct tevent_req *subreq)
465 struct dns_udp_socket *sock = tevent_req_callback_data(subreq,
466 struct dns_udp_socket);
467 struct dns_udp_call *call;
473 call = talloc(sock, struct dns_udp_call);
479 len = tdgram_recvfrom_recv(subreq, &sys_errno,
480 call, &buf, &call->src);
488 call->in.length = len;
490 DEBUG(10,("Received DNS UDP packet of length %lu from %s\n",
491 (long)call->in.length,
492 tsocket_address_string(call->src, call)));
494 /* Call dns_process */
495 err = dns_process(sock->dns_socket->dns, call, &call->in, &call->out);
496 if (!W_ERROR_IS_OK(err)) {
498 DEBUG(0, ("dns_process returned %s\n", win_errstr(err)));
502 subreq = tdgram_sendto_queue_send(call,
503 sock->dns_socket->dns->task->event_ctx,
509 if (subreq == NULL) {
513 tevent_req_set_callback(subreq, dns_udp_call_sendto_done, call);
516 subreq = tdgram_recvfrom_send(sock,
517 sock->dns_socket->dns->task->event_ctx,
519 if (subreq == NULL) {
520 task_server_terminate(sock->dns_socket->dns->task,
521 "no memory for tdgram_recvfrom_send",
525 tevent_req_set_callback(subreq, dns_udp_call_loop, sock);
528 static void dns_udp_call_sendto_done(struct tevent_req *subreq)
530 struct dns_udp_call *call = tevent_req_callback_data(subreq,
531 struct dns_udp_call);
535 ret = tdgram_sendto_queue_recv(subreq, &sys_errno);
537 /* We don't care about errors */
543 start listening on the given address
545 static NTSTATUS dns_add_socket(struct dns_server *dns,
546 const struct model_ops *model_ops,
551 struct dns_socket *dns_socket;
552 struct dns_udp_socket *dns_udp_socket;
553 struct tevent_req *udpsubreq;
557 dns_socket = talloc(dns, struct dns_socket);
558 NT_STATUS_HAVE_NO_MEMORY(dns_socket);
560 dns_socket->dns = dns;
562 ret = tsocket_address_inet_from_strings(dns_socket, "ip",
564 &dns_socket->local_address);
566 status = map_nt_error_from_unix_common(errno);
570 status = stream_setup_socket(dns->task,
571 dns->task->event_ctx,
575 "ip", address, &port,
576 lpcfg_socket_options(dns->task->lp_ctx),
578 if (!NT_STATUS_IS_OK(status)) {
579 DEBUG(0,("Failed to bind to %s:%u TCP - %s\n",
580 address, port, nt_errstr(status)));
581 talloc_free(dns_socket);
585 dns_udp_socket = talloc(dns_socket, struct dns_udp_socket);
586 NT_STATUS_HAVE_NO_MEMORY(dns_udp_socket);
588 dns_udp_socket->dns_socket = dns_socket;
590 ret = tdgram_inet_udp_socket(dns_socket->local_address,
593 &dns_udp_socket->dgram);
595 status = map_nt_error_from_unix_common(errno);
596 DEBUG(0,("Failed to bind to %s:%u UDP - %s\n",
597 address, port, nt_errstr(status)));
601 dns_udp_socket->send_queue = tevent_queue_create(dns_udp_socket,
602 "dns_udp_send_queue");
603 NT_STATUS_HAVE_NO_MEMORY(dns_udp_socket->send_queue);
605 udpsubreq = tdgram_recvfrom_send(dns_udp_socket,
606 dns->task->event_ctx,
607 dns_udp_socket->dgram);
608 NT_STATUS_HAVE_NO_MEMORY(udpsubreq);
609 tevent_req_set_callback(udpsubreq, dns_udp_call_loop, dns_udp_socket);
615 setup our listening sockets on the configured network interfaces
617 static NTSTATUS dns_startup_interfaces(struct dns_server *dns, struct loadparm_context *lp_ctx,
618 struct interface *ifaces)
620 const struct model_ops *model_ops;
622 TALLOC_CTX *tmp_ctx = talloc_new(dns);
626 /* within the dns task we want to be a single process, so
627 ask for the single process model ops and pass these to the
628 stream_setup_socket() call. */
629 model_ops = process_model_startup("single");
631 DEBUG(0,("Can't find 'single' process model_ops\n"));
632 return NT_STATUS_INTERNAL_ERROR;
635 num_interfaces = iface_list_count(ifaces);
637 for (i=0; i<num_interfaces; i++) {
638 const char *address = talloc_strdup(tmp_ctx, iface_list_n_ip(ifaces, i));
640 status = dns_add_socket(dns, model_ops, "dns", address, DNS_SERVICE_PORT);
641 NT_STATUS_NOT_OK_RETURN(status);
644 talloc_free(tmp_ctx);
649 static int dns_server_sort_zones(struct ldb_message **m1, struct ldb_message **m2)
654 n1 = ldb_msg_find_attr_as_string(*m1, "name", NULL);
655 n2 = ldb_msg_find_attr_as_string(*m2, "name", NULL);
660 /* If the string lengths are not equal just sort by length */
662 /* If m1 is the larger zone name, return it first */
666 /*TODO: We need to compare DNs here, we want the DomainDNSZones first */
670 static void dns_task_init(struct task_server *task)
672 struct dns_server *dns;
674 struct interface *ifaces;
676 struct ldb_result *res;
677 static const char * const attrs[] = { "name", NULL};
680 switch (lpcfg_server_role(task->lp_ctx)) {
681 case ROLE_STANDALONE:
682 task_server_terminate(task, "dns: no DNS required in standalone configuration", false);
684 case ROLE_DOMAIN_MEMBER:
685 task_server_terminate(task, "dns: no DNS required in member server configuration", false);
687 case ROLE_DOMAIN_CONTROLLER:
688 /* Yes, we want a DNS */
692 load_interface_list(task, task->lp_ctx, &ifaces);
694 if (iface_list_count(ifaces) == 0) {
695 task_server_terminate(task, "dns: no network interfaces configured", false);
699 task_server_set_title(task, "task[dns]");
701 dns = talloc_zero(task, struct dns_server);
703 task_server_terminate(task, "dns: out of memory", true);
709 dns->samdb = samdb_connect(dns, dns->task->event_ctx, dns->task->lp_ctx,
710 system_session(dns->task->lp_ctx), 0);
712 task_server_terminate(task, "dns: samdb_connect failed", true);
716 // TODO: this search does not work against windows
717 ret = dsdb_search(dns->samdb, dns, &res, NULL, LDB_SCOPE_SUBTREE,
718 attrs, DSDB_SEARCH_SEARCH_ALL_PARTITIONS, "(objectClass=dnsZone)");
719 if (ret != LDB_SUCCESS) {
720 task_server_terminate(task,
721 "dns: failed to look up root DNS zones",
726 TYPESAFE_QSORT(res->msgs, res->count, dns_server_sort_zones);
728 for (i=0; i < res->count; i++) {
729 struct dns_server_zone *z;
731 z = talloc_zero(dns, struct dns_server_zone);
735 z->name = ldb_msg_find_attr_as_string(res->msgs[i], "name", NULL);
736 z->dn = talloc_move(z, &res->msgs[i]->dn);
738 DLIST_ADD_END(dns->zones, z, NULL);
741 status = dns_startup_interfaces(dns, task->lp_ctx, ifaces);
742 if (!NT_STATUS_IS_OK(status)) {
743 task_server_terminate(task, "dns failed to setup interfaces", true);
748 NTSTATUS server_service_dns_init(void)
750 return register_server_service("dns", dns_task_init);