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 struct dns_request_state *state;
104 struct dns_name_packet *in_packet;
105 struct dns_name_packet *out_packet;
106 struct dns_res_rec *answers = NULL, *nsrecs = NULL, *additional = NULL;
107 uint16_t num_answers = 0 , num_nsrecs = 0, num_additional = 0;
109 if (in->length < 12) {
110 return NT_STATUS_INVALID_PARAMETER;
113 state = talloc_zero(mem_ctx, struct dns_request_state);
115 in_packet = talloc_zero(state, struct dns_name_packet);
116 /* TODO: We don't really need an out_packet. */
117 out_packet = talloc_zero(state, struct dns_name_packet);
119 if (in_packet == NULL) return NT_STATUS_NO_MEMORY;
120 if (out_packet == NULL) return NT_STATUS_NO_MEMORY;
122 dump_data(8, in->data, in->length);
124 ndr_err = ndr_pull_struct_blob(in, in_packet, in_packet,
125 (ndr_pull_flags_fn_t)ndr_pull_dns_name_packet);
126 if (!NDR_ERR_CODE_IS_SUCCESS(ndr_err)) {
127 TALLOC_FREE(in_packet);
128 DEBUG(0, ("Failed to parse packet %d!\n", ndr_err));
131 out->data[2] |= 0x80; /* Toggle DNS_FLAG_REPLY */
132 out->data[3] |= DNS_RCODE_FORMERR;
137 NDR_PRINT_DEBUG(dns_name_packet, in_packet);
139 *out_packet = *in_packet;
140 state->flags |= in_packet->operation | DNS_FLAG_REPLY;
142 if (lpcfg_dns_recursive_queries(dns->task->lp_ctx)) {
143 state->flags |= DNS_FLAG_RECURSION_AVAIL;
146 switch (in_packet->operation & DNS_OPCODE) {
147 case DNS_OPCODE_QUERY:
149 ret = dns_server_process_query(dns, state,
150 out_packet, in_packet,
151 &answers, &num_answers,
152 &nsrecs, &num_nsrecs,
153 &additional, &num_additional);
156 case DNS_OPCODE_UPDATE:
157 ret = dns_server_process_update(dns, state,
158 out_packet, in_packet,
159 &answers, &num_answers,
160 &nsrecs, &num_nsrecs,
161 &additional, &num_additional);
164 ret = WERR_DNS_ERROR_RCODE_NOT_IMPLEMENTED;
168 if (W_ERROR_IS_OK(ret)) {
169 out_packet->ancount = num_answers;
170 out_packet->answers = answers;
172 out_packet->nscount = num_nsrecs;
173 out_packet->nsrecs = nsrecs;
175 out_packet->arcount = num_additional;
176 out_packet->additional = additional;
178 out_packet->operation |= werr_to_dns_err(ret);
181 out_packet->operation |= state->flags;
184 NDR_PRINT_DEBUG(dns_name_packet, out_packet);
186 ndr_err = ndr_push_struct_blob(out, out_packet, out_packet,
187 (ndr_push_flags_fn_t)ndr_push_dns_name_packet);
188 if (!NDR_ERR_CODE_IS_SUCCESS(ndr_err)) {
189 TALLOC_FREE(in_packet);
190 TALLOC_FREE(out_packet);
191 DEBUG(0, ("Failed to push packet %d!\n", ndr_err));
194 out->data[2] |= 0x80; /* Toggle DNS_FLAG_REPLY */
195 out->data[3] |= DNS_RCODE_SERVFAIL;
200 dump_data(8, out->data, out->length);
204 struct dns_tcp_call {
205 struct dns_tcp_connection *dns_conn;
209 struct iovec out_iov[2];
212 static void dns_tcp_call_writev_done(struct tevent_req *subreq);
214 static void dns_tcp_call_loop(struct tevent_req *subreq)
216 struct dns_tcp_connection *dns_conn = tevent_req_callback_data(subreq,
217 struct dns_tcp_connection);
218 struct dns_tcp_call *call;
221 call = talloc(dns_conn, struct dns_tcp_call);
223 dns_tcp_terminate_connection(dns_conn, "dns_tcp_call_loop: "
224 "no memory for dns_tcp_call");
227 call->dns_conn = dns_conn;
229 status = tstream_read_pdu_blob_recv(subreq,
233 if (!NT_STATUS_IS_OK(status)) {
236 reason = talloc_asprintf(call, "dns_tcp_call_loop: "
237 "tstream_read_pdu_blob_recv() - %s",
240 reason = nt_errstr(status);
243 dns_tcp_terminate_connection(dns_conn, reason);
247 DEBUG(10,("Received DNS TCP packet of length %lu from %s\n",
248 (long) call->in.length,
249 tsocket_address_string(dns_conn->conn->remote_address, call)));
251 /* skip length header */
253 call->in.length -= 2;
256 status = dns_process(dns_conn->dns_socket->dns, call, &call->in, &call->out);
257 if (!NT_STATUS_IS_OK(status)) {
258 DEBUG(0, ("dns_process returned %s\n", nt_errstr(status)));
259 dns_tcp_terminate_connection(dns_conn,
260 "dns_tcp_call_loop: process function failed");
264 /* First add the length of the out buffer */
265 RSSVAL(call->out_hdr, 0, call->out.length);
266 call->out_iov[0].iov_base = (char *) call->out_hdr;
267 call->out_iov[0].iov_len = 2;
269 call->out_iov[1].iov_base = (char *) call->out.data;
270 call->out_iov[1].iov_len = call->out.length;
272 subreq = tstream_writev_queue_send(call,
273 dns_conn->conn->event.ctx,
275 dns_conn->send_queue,
277 if (subreq == NULL) {
278 dns_tcp_terminate_connection(dns_conn, "dns_tcp_call_loop: "
279 "no memory for tstream_writev_queue_send");
282 tevent_req_set_callback(subreq, dns_tcp_call_writev_done, call);
285 * The dns tcp pdu's has the length as 2 byte (initial_read_size),
286 * packet_full_request_u16 provides the pdu length then.
288 subreq = tstream_read_pdu_blob_send(dns_conn,
289 dns_conn->conn->event.ctx,
291 2, /* initial_read_size */
292 packet_full_request_u16,
294 if (subreq == NULL) {
295 dns_tcp_terminate_connection(dns_conn, "dns_tcp_call_loop: "
296 "no memory for tstream_read_pdu_blob_send");
299 tevent_req_set_callback(subreq, dns_tcp_call_loop, dns_conn);
302 static void dns_tcp_call_writev_done(struct tevent_req *subreq)
304 struct dns_tcp_call *call = tevent_req_callback_data(subreq,
305 struct dns_tcp_call);
309 rc = tstream_writev_queue_recv(subreq, &sys_errno);
314 reason = talloc_asprintf(call, "dns_tcp_call_writev_done: "
315 "tstream_writev_queue_recv() - %d:%s",
316 sys_errno, strerror(sys_errno));
318 reason = "dns_tcp_call_writev_done: tstream_writev_queue_recv() failed";
321 dns_tcp_terminate_connection(call->dns_conn, reason);
325 /* We don't care about errors */
331 called when we get a new connection
333 static void dns_tcp_accept(struct stream_connection *conn)
335 struct dns_socket *dns_socket;
336 struct dns_tcp_connection *dns_conn;
337 struct tevent_req *subreq;
340 dns_conn = talloc_zero(conn, struct dns_tcp_connection);
341 if (dns_conn == NULL) {
342 stream_terminate_connection(conn,
343 "dns_tcp_accept: out of memory");
347 dns_conn->send_queue = tevent_queue_create(conn, "dns_tcp_accept");
348 if (dns_conn->send_queue == NULL) {
349 stream_terminate_connection(conn,
350 "dns_tcp_accept: out of memory");
354 dns_socket = talloc_get_type(conn->private_data, struct dns_socket);
356 TALLOC_FREE(conn->event.fde);
358 rc = tstream_bsd_existing_socket(dns_conn,
359 socket_get_fd(conn->socket),
362 stream_terminate_connection(conn,
363 "dns_tcp_accept: out of memory");
367 dns_conn->conn = conn;
368 dns_conn->dns_socket = dns_socket;
369 conn->private_data = dns_conn;
372 * The dns tcp pdu's has the length as 2 byte (initial_read_size),
373 * packet_full_request_u16 provides the pdu length then.
375 subreq = tstream_read_pdu_blob_send(dns_conn,
376 dns_conn->conn->event.ctx,
378 2, /* initial_read_size */
379 packet_full_request_u16,
381 if (subreq == NULL) {
382 dns_tcp_terminate_connection(dns_conn, "dns_tcp_accept: "
383 "no memory for tstream_read_pdu_blob_send");
386 tevent_req_set_callback(subreq, dns_tcp_call_loop, dns_conn);
389 static const struct stream_server_ops dns_tcp_stream_ops = {
391 .accept_connection = dns_tcp_accept,
392 .recv_handler = dns_tcp_recv,
393 .send_handler = dns_tcp_send
396 struct dns_udp_call {
397 struct tsocket_address *src;
402 static void dns_udp_call_sendto_done(struct tevent_req *subreq);
404 static void dns_udp_call_loop(struct tevent_req *subreq)
406 struct dns_udp_socket *sock = tevent_req_callback_data(subreq,
407 struct dns_udp_socket);
408 struct dns_udp_call *call;
414 call = talloc(sock, struct dns_udp_call);
420 len = tdgram_recvfrom_recv(subreq, &sys_errno,
421 call, &buf, &call->src);
429 call->in.length = len;
431 DEBUG(10,("Received DNS UDP packet of length %lu from %s\n",
432 (long)call->in.length,
433 tsocket_address_string(call->src, call)));
435 /* Call dns_process */
436 status = dns_process(sock->dns_socket->dns, call, &call->in, &call->out);
437 if (!NT_STATUS_IS_OK(status)) {
439 DEBUG(0, ("dns_process returned %s\n", nt_errstr(status)));
443 subreq = tdgram_sendto_queue_send(call,
444 sock->dns_socket->dns->task->event_ctx,
450 if (subreq == NULL) {
454 tevent_req_set_callback(subreq, dns_udp_call_sendto_done, call);
457 subreq = tdgram_recvfrom_send(sock,
458 sock->dns_socket->dns->task->event_ctx,
460 if (subreq == NULL) {
461 task_server_terminate(sock->dns_socket->dns->task,
462 "no memory for tdgram_recvfrom_send",
466 tevent_req_set_callback(subreq, dns_udp_call_loop, sock);
469 static void dns_udp_call_sendto_done(struct tevent_req *subreq)
471 struct dns_udp_call *call = tevent_req_callback_data(subreq,
472 struct dns_udp_call);
476 ret = tdgram_sendto_queue_recv(subreq, &sys_errno);
478 /* We don't care about errors */
484 start listening on the given address
486 static NTSTATUS dns_add_socket(struct dns_server *dns,
487 const struct model_ops *model_ops,
492 struct dns_socket *dns_socket;
493 struct dns_udp_socket *dns_udp_socket;
494 struct tevent_req *udpsubreq;
498 dns_socket = talloc(dns, struct dns_socket);
499 NT_STATUS_HAVE_NO_MEMORY(dns_socket);
501 dns_socket->dns = dns;
503 ret = tsocket_address_inet_from_strings(dns_socket, "ip",
505 &dns_socket->local_address);
507 status = map_nt_error_from_unix_common(errno);
511 status = stream_setup_socket(dns->task,
512 dns->task->event_ctx,
516 "ip", address, &port,
517 lpcfg_socket_options(dns->task->lp_ctx),
519 if (!NT_STATUS_IS_OK(status)) {
520 DEBUG(0,("Failed to bind to %s:%u TCP - %s\n",
521 address, port, nt_errstr(status)));
522 talloc_free(dns_socket);
526 dns_udp_socket = talloc(dns_socket, struct dns_udp_socket);
527 NT_STATUS_HAVE_NO_MEMORY(dns_udp_socket);
529 dns_udp_socket->dns_socket = dns_socket;
531 ret = tdgram_inet_udp_socket(dns_socket->local_address,
534 &dns_udp_socket->dgram);
536 status = map_nt_error_from_unix_common(errno);
537 DEBUG(0,("Failed to bind to %s:%u UDP - %s\n",
538 address, port, nt_errstr(status)));
542 dns_udp_socket->send_queue = tevent_queue_create(dns_udp_socket,
543 "dns_udp_send_queue");
544 NT_STATUS_HAVE_NO_MEMORY(dns_udp_socket->send_queue);
546 udpsubreq = tdgram_recvfrom_send(dns_udp_socket,
547 dns->task->event_ctx,
548 dns_udp_socket->dgram);
549 NT_STATUS_HAVE_NO_MEMORY(udpsubreq);
550 tevent_req_set_callback(udpsubreq, dns_udp_call_loop, dns_udp_socket);
556 setup our listening sockets on the configured network interfaces
558 static NTSTATUS dns_startup_interfaces(struct dns_server *dns, struct loadparm_context *lp_ctx,
559 struct interface *ifaces)
561 const struct model_ops *model_ops;
563 TALLOC_CTX *tmp_ctx = talloc_new(dns);
567 /* within the dns task we want to be a single process, so
568 ask for the single process model ops and pass these to the
569 stream_setup_socket() call. */
570 model_ops = process_model_startup("single");
572 DEBUG(0,("Can't find 'single' process model_ops\n"));
573 return NT_STATUS_INTERNAL_ERROR;
576 num_interfaces = iface_list_count(ifaces);
578 for (i=0; i<num_interfaces; i++) {
579 const char *address = talloc_strdup(tmp_ctx, iface_list_n_ip(ifaces, i));
581 status = dns_add_socket(dns, model_ops, "dns", address, DNS_SERVICE_PORT);
582 NT_STATUS_NOT_OK_RETURN(status);
585 talloc_free(tmp_ctx);
590 static int dns_server_sort_zones(struct ldb_message **m1, struct ldb_message **m2)
595 n1 = ldb_msg_find_attr_as_string(*m1, "name", NULL);
596 n2 = ldb_msg_find_attr_as_string(*m2, "name", NULL);
601 /* If the string lengths are not equal just sort by length */
603 /* If m1 is the larger zone name, return it first */
607 /*TODO: We need to compare DNs here, we want the DomainDNSZones first */
611 static void dns_task_init(struct task_server *task)
613 struct dns_server *dns;
615 struct interface *ifaces;
617 struct ldb_result *res;
618 static const char * const attrs[] = { "name", NULL};
621 switch (lpcfg_server_role(task->lp_ctx)) {
622 case ROLE_STANDALONE:
623 task_server_terminate(task, "dns: no DNS required in standalone configuration", false);
625 case ROLE_DOMAIN_MEMBER:
626 task_server_terminate(task, "dns: no DNS required in member server configuration", false);
628 case ROLE_DOMAIN_CONTROLLER:
629 /* Yes, we want a DNS */
633 load_interface_list(task, task->lp_ctx, &ifaces);
635 if (iface_list_count(ifaces) == 0) {
636 task_server_terminate(task, "dns: no network interfaces configured", false);
640 task_server_set_title(task, "task[dns]");
642 dns = talloc_zero(task, struct dns_server);
644 task_server_terminate(task, "dns: out of memory", true);
650 dns->samdb = samdb_connect(dns, dns->task->event_ctx, dns->task->lp_ctx,
651 system_session(dns->task->lp_ctx), 0);
653 task_server_terminate(task, "dns: samdb_connect failed", true);
657 // TODO: this search does not work against windows
658 ret = dsdb_search(dns->samdb, dns, &res, NULL, LDB_SCOPE_SUBTREE,
659 attrs, DSDB_SEARCH_SEARCH_ALL_PARTITIONS, "(objectClass=dnsZone)");
660 if (ret != LDB_SUCCESS) {
661 task_server_terminate(task,
662 "dns: failed to look up root DNS zones",
667 TYPESAFE_QSORT(res->msgs, res->count, dns_server_sort_zones);
669 for (i=0; i < res->count; i++) {
670 struct dns_server_zone *z;
672 z = talloc_zero(dns, struct dns_server_zone);
676 z->name = ldb_msg_find_attr_as_string(res->msgs[i], "name", NULL);
677 z->dn = talloc_move(z, &res->msgs[i]->dn);
679 DLIST_ADD_END(dns->zones, z, NULL);
682 status = dns_startup_interfaces(dns, task->lp_ctx, ifaces);
683 if (!NT_STATUS_IS_OK(status)) {
684 task_server_terminate(task, "dns failed to setup interfaces", true);
689 NTSTATUS server_service_dns_init(void)
691 return register_server_service("dns", dns_task_init);