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 /* hold information about one dns socket */
48 struct dns_server *dns;
49 struct tsocket_address *local_address;
52 struct dns_udp_socket {
53 struct dns_socket *dns_socket;
54 struct tdgram_context *dgram;
55 struct tevent_queue *send_queue;
59 state of an open tcp connection
61 struct dns_tcp_connection {
62 /* stream connection we belong to */
63 struct stream_connection *conn;
65 /* the dns_server the connection belongs to */
66 struct dns_socket *dns_socket;
68 struct tstream_context *tstream;
70 struct tevent_queue *send_queue;
73 static void dns_tcp_terminate_connection(struct dns_tcp_connection *dnsconn, const char *reason)
75 stream_terminate_connection(dnsconn->conn, reason);
78 static void dns_tcp_recv(struct stream_connection *conn, uint16_t flags)
80 struct dns_tcp_connection *dnsconn = talloc_get_type(conn->private_data,
81 struct dns_tcp_connection);
82 /* this should never be triggered! */
83 dns_tcp_terminate_connection(dnsconn, "dns_tcp_recv: called");
86 static void dns_tcp_send(struct stream_connection *conn, uint16_t flags)
88 struct dns_tcp_connection *dnsconn = talloc_get_type(conn->private_data,
89 struct dns_tcp_connection);
90 /* this should never be triggered! */
91 dns_tcp_terminate_connection(dnsconn, "dns_tcp_send: called");
94 static NTSTATUS dns_process(struct dns_server *dns,
99 enum ndr_err_code ndr_err;
101 struct dns_name_packet *in_packet;
102 struct dns_name_packet *out_packet;
103 struct dns_res_rec *answers = NULL, *nsrecs = NULL, *additional = NULL;
104 uint16_t num_answers = 0 , num_nsrecs = 0, num_additional = 0;
106 if (in->length < 12) {
107 return NT_STATUS_INVALID_PARAMETER;
110 in_packet = talloc_zero(mem_ctx, struct dns_name_packet);
111 /* TODO: We don't really need an out_packet. */
112 out_packet = talloc_zero(mem_ctx, struct dns_name_packet);
114 if (in_packet == NULL) return NT_STATUS_NO_MEMORY;
115 if (out_packet == NULL) return NT_STATUS_NO_MEMORY;
117 dump_data(2, in->data, in->length);
119 ndr_err = ndr_pull_struct_blob(in, in_packet, in_packet,
120 (ndr_pull_flags_fn_t)ndr_pull_dns_name_packet);
121 if (!NDR_ERR_CODE_IS_SUCCESS(ndr_err)) {
122 TALLOC_FREE(in_packet);
123 DEBUG(0, ("Failed to parse packet %d!\n", ndr_err));
126 out->data[2] |= 0x80; /* Toggle DNS_FLAG_REPLY */
127 out->data[3] |= DNS_RCODE_FORMERR;
132 NDR_PRINT_DEBUG(dns_name_packet, in_packet);
133 *out_packet = *in_packet;
134 out_packet->operation |= DNS_FLAG_REPLY;
136 switch (in_packet->operation & DNS_OPCODE) {
137 case DNS_OPCODE_QUERY:
139 ret = dns_server_process_query(dns, out_packet, in_packet,
140 &answers, &num_answers,
141 &nsrecs, &num_nsrecs,
142 &additional, &num_additional);
145 case DNS_OPCODE_REGISTER:
146 ret = dns_server_process_update(dns, out_packet, in_packet,
147 answers, num_answers,
148 &nsrecs, &num_nsrecs,
149 &additional, &num_additional);
152 ret = WERR_DNS_ERROR_RCODE_NOT_IMPLEMENTED;
156 if (W_ERROR_IS_OK(ret)) {
157 out_packet->ancount = num_answers;
158 out_packet->answers = answers;
160 out_packet->nscount = num_nsrecs;
161 out_packet->nsrecs = nsrecs;
163 out_packet->arcount = num_additional;
164 out_packet->additional = additional;
166 out_packet->operation |= werr_to_dns_err(ret);
169 NDR_PRINT_DEBUG(dns_name_packet, out_packet);
170 ndr_err = ndr_push_struct_blob(out, out_packet, out_packet,
171 (ndr_push_flags_fn_t)ndr_push_dns_name_packet);
172 if (!NDR_ERR_CODE_IS_SUCCESS(ndr_err)) {
173 TALLOC_FREE(in_packet);
174 TALLOC_FREE(out_packet);
175 DEBUG(0, ("Failed to push packet %d!\n", ndr_err));
178 out->data[2] |= 0x80; /* Toggle DNS_FLAG_REPLY */
179 out->data[3] |= DNS_RCODE_SERVFAIL;
184 dump_data(2, out->data, out->length);
188 struct dns_tcp_call {
189 struct dns_tcp_connection *dns_conn;
193 struct iovec out_iov[2];
196 static void dns_tcp_call_writev_done(struct tevent_req *subreq);
198 static void dns_tcp_call_loop(struct tevent_req *subreq)
200 struct dns_tcp_connection *dns_conn = tevent_req_callback_data(subreq,
201 struct dns_tcp_connection);
202 struct dns_tcp_call *call;
205 call = talloc(dns_conn, struct dns_tcp_call);
207 dns_tcp_terminate_connection(dns_conn, "dns_tcp_call_loop: "
208 "no memory for dns_tcp_call");
211 call->dns_conn = dns_conn;
213 status = tstream_read_pdu_blob_recv(subreq,
217 if (!NT_STATUS_IS_OK(status)) {
220 reason = talloc_asprintf(call, "dns_tcp_call_loop: "
221 "tstream_read_pdu_blob_recv() - %s",
224 reason = nt_errstr(status);
227 dns_tcp_terminate_connection(dns_conn, reason);
231 DEBUG(10,("Received krb5 TCP packet of length %lu from %s\n",
232 (long) call->in.length,
233 tsocket_address_string(dns_conn->conn->remote_address, call)));
235 /* skip length header */
237 call->in.length -= 4;
240 status = dns_process(dns_conn->dns_socket->dns, call, &call->in, &call->out);
241 if (!NT_STATUS_IS_OK(status)) {
242 DEBUG(0, ("dns_process returned %s\n", nt_errstr(status)));
243 dns_tcp_terminate_connection(dns_conn,
244 "dns_tcp_call_loop: process function failed");
248 /* First add the length of the out buffer */
249 RSIVAL(call->out_hdr, 0, call->out.length);
250 call->out_iov[0].iov_base = (char *) call->out_hdr;
251 call->out_iov[0].iov_len = 4;
253 call->out_iov[1].iov_base = (char *) call->out.data;
254 call->out_iov[1].iov_len = call->out.length;
256 subreq = tstream_writev_queue_send(call,
257 dns_conn->conn->event.ctx,
259 dns_conn->send_queue,
261 if (subreq == NULL) {
262 dns_tcp_terminate_connection(dns_conn, "dns_tcp_call_loop: "
263 "no memory for tstream_writev_queue_send");
266 tevent_req_set_callback(subreq, dns_tcp_call_writev_done, call);
269 * The krb5 tcp pdu's has the length as 4 byte (initial_read_size),
270 * packet_full_request_u32 provides the pdu length then.
272 subreq = tstream_read_pdu_blob_send(dns_conn,
273 dns_conn->conn->event.ctx,
275 4, /* initial_read_size */
276 packet_full_request_u32,
278 if (subreq == NULL) {
279 dns_tcp_terminate_connection(dns_conn, "dns_tcp_call_loop: "
280 "no memory for tstream_read_pdu_blob_send");
283 tevent_req_set_callback(subreq, dns_tcp_call_loop, dns_conn);
286 static void dns_tcp_call_writev_done(struct tevent_req *subreq)
288 struct dns_tcp_call *call = tevent_req_callback_data(subreq,
289 struct dns_tcp_call);
293 rc = tstream_writev_queue_recv(subreq, &sys_errno);
298 reason = talloc_asprintf(call, "dns_tcp_call_writev_done: "
299 "tstream_writev_queue_recv() - %d:%s",
300 sys_errno, strerror(sys_errno));
302 reason = "dns_tcp_call_writev_done: tstream_writev_queue_recv() failed";
305 dns_tcp_terminate_connection(call->dns_conn, reason);
309 /* We don't care about errors */
315 called when we get a new connection
317 static void dns_tcp_accept(struct stream_connection *conn)
319 struct dns_socket *dns_socket;
320 struct dns_tcp_connection *dns_conn;
321 struct tevent_req *subreq;
324 dns_conn = talloc_zero(conn, struct dns_tcp_connection);
325 if (dns_conn == NULL) {
326 stream_terminate_connection(conn,
327 "dns_tcp_accept: out of memory");
331 dns_conn->send_queue = tevent_queue_create(conn, "dns_tcp_accept");
332 if (dns_conn->send_queue == NULL) {
333 stream_terminate_connection(conn,
334 "dns_tcp_accept: out of memory");
338 dns_socket = talloc_get_type(conn->private_data, struct dns_socket);
340 TALLOC_FREE(conn->event.fde);
342 rc = tstream_bsd_existing_socket(dns_conn,
343 socket_get_fd(conn->socket),
346 stream_terminate_connection(conn,
347 "dns_tcp_accept: out of memory");
351 dns_conn->conn = conn;
352 dns_conn->dns_socket = dns_socket;
353 conn->private_data = dns_conn;
356 * The krb5 tcp pdu's has the length as 4 byte (initial_read_size),
357 * packet_full_request_u32 provides the pdu length then.
359 subreq = tstream_read_pdu_blob_send(dns_conn,
360 dns_conn->conn->event.ctx,
362 4, /* initial_read_size */
363 packet_full_request_u32,
365 if (subreq == NULL) {
366 dns_tcp_terminate_connection(dns_conn, "dns_tcp_accept: "
367 "no memory for tstream_read_pdu_blob_send");
370 tevent_req_set_callback(subreq, dns_tcp_call_loop, dns_conn);
373 static const struct stream_server_ops dns_tcp_stream_ops = {
375 .accept_connection = dns_tcp_accept,
376 .recv_handler = dns_tcp_recv,
377 .send_handler = dns_tcp_send
380 struct dns_udp_call {
381 struct tsocket_address *src;
386 static void dns_udp_call_sendto_done(struct tevent_req *subreq);
388 static void dns_udp_call_loop(struct tevent_req *subreq)
390 struct dns_udp_socket *sock = tevent_req_callback_data(subreq,
391 struct dns_udp_socket);
392 struct dns_udp_call *call;
398 call = talloc(sock, struct dns_udp_call);
404 len = tdgram_recvfrom_recv(subreq, &sys_errno,
405 call, &buf, &call->src);
413 call->in.length = len;
415 DEBUG(10,("Received krb5 UDP packet of length %lu from %s\n",
416 (long)call->in.length,
417 tsocket_address_string(call->src, call)));
420 status = dns_process(sock->dns_socket->dns, call, &call->in, &call->out);
421 if (!NT_STATUS_IS_OK(status)) {
423 DEBUG(0, ("dns_process returned %s\n", nt_errstr(status)));
427 subreq = tdgram_sendto_queue_send(call,
428 sock->dns_socket->dns->task->event_ctx,
434 if (subreq == NULL) {
438 tevent_req_set_callback(subreq, dns_udp_call_sendto_done, call);
441 subreq = tdgram_recvfrom_send(sock,
442 sock->dns_socket->dns->task->event_ctx,
444 if (subreq == NULL) {
445 task_server_terminate(sock->dns_socket->dns->task,
446 "no memory for tdgram_recvfrom_send",
450 tevent_req_set_callback(subreq, dns_udp_call_loop, sock);
453 static void dns_udp_call_sendto_done(struct tevent_req *subreq)
455 struct dns_udp_call *call = tevent_req_callback_data(subreq,
456 struct dns_udp_call);
460 ret = tdgram_sendto_queue_recv(subreq, &sys_errno);
462 /* We don't care about errors */
468 start listening on the given address
470 static NTSTATUS dns_add_socket(struct dns_server *dns,
471 const struct model_ops *model_ops,
476 struct dns_socket *dns_socket;
477 struct dns_udp_socket *dns_udp_socket;
478 struct tevent_req *udpsubreq;
482 dns_socket = talloc(dns, struct dns_socket);
483 NT_STATUS_HAVE_NO_MEMORY(dns_socket);
485 dns_socket->dns = dns;
487 ret = tsocket_address_inet_from_strings(dns_socket, "ip",
489 &dns_socket->local_address);
491 status = map_nt_error_from_unix(errno);
495 status = stream_setup_socket(dns->task->event_ctx,
499 "ip", address, &port,
500 lpcfg_socket_options(dns->task->lp_ctx),
502 if (!NT_STATUS_IS_OK(status)) {
503 DEBUG(0,("Failed to bind to %s:%u TCP - %s\n",
504 address, port, nt_errstr(status)));
505 talloc_free(dns_socket);
509 dns_udp_socket = talloc(dns_socket, struct dns_udp_socket);
510 NT_STATUS_HAVE_NO_MEMORY(dns_udp_socket);
512 dns_udp_socket->dns_socket = dns_socket;
514 ret = tdgram_inet_udp_socket(dns_socket->local_address,
517 &dns_udp_socket->dgram);
519 status = map_nt_error_from_unix(errno);
520 DEBUG(0,("Failed to bind to %s:%u UDP - %s\n",
521 address, port, nt_errstr(status)));
525 dns_udp_socket->send_queue = tevent_queue_create(dns_udp_socket,
526 "dns_udp_send_queue");
527 NT_STATUS_HAVE_NO_MEMORY(dns_udp_socket->send_queue);
529 udpsubreq = tdgram_recvfrom_send(dns_udp_socket,
530 dns->task->event_ctx,
531 dns_udp_socket->dgram);
532 NT_STATUS_HAVE_NO_MEMORY(udpsubreq);
533 tevent_req_set_callback(udpsubreq, dns_udp_call_loop, dns_udp_socket);
539 setup our listening sockets on the configured network interfaces
541 static NTSTATUS dns_startup_interfaces(struct dns_server *dns, struct loadparm_context *lp_ctx,
542 struct interface *ifaces)
544 const struct model_ops *model_ops;
546 TALLOC_CTX *tmp_ctx = talloc_new(dns);
550 /* within the dns task we want to be a single process, so
551 ask for the single process model ops and pass these to the
552 stream_setup_socket() call. */
553 model_ops = process_model_startup(dns->task->event_ctx, "single");
555 DEBUG(0,("Can't find 'single' process model_ops\n"));
556 return NT_STATUS_INTERNAL_ERROR;
559 num_interfaces = iface_count(ifaces);
561 for (i=0; i<num_interfaces; i++) {
562 const char *address = talloc_strdup(tmp_ctx, iface_n_ip(ifaces, i));
564 status = dns_add_socket(dns, model_ops, "dns", address, DNS_SERVICE_PORT);
565 NT_STATUS_NOT_OK_RETURN(status);
568 talloc_free(tmp_ctx);
573 static int dns_server_sort_zones(struct ldb_message **m1, struct ldb_message **m2)
578 n1 = ldb_msg_find_attr_as_string(*m1, "name", NULL);
579 n2 = ldb_msg_find_attr_as_string(*m2, "name", NULL);
584 /* If the string lengths are not equal just sort by length */
586 /* If m1 is the larger zone name, return it first */
590 /*TODO: We need to compare DNs here, we want the DomainDNSZones first */
594 static void dns_task_init(struct task_server *task)
596 struct dns_server *dns;
598 struct interface *ifaces;
600 struct ldb_result *res;
601 struct ldb_dn *rootdn;
602 static const char * const attrs[] = { "name", NULL};
605 switch (lpcfg_server_role(task->lp_ctx)) {
606 case ROLE_STANDALONE:
607 task_server_terminate(task, "dns: no DNS required in standalone configuration", false);
609 case ROLE_DOMAIN_MEMBER:
610 task_server_terminate(task, "dns: no DNS required in member server configuration", false);
612 case ROLE_DOMAIN_CONTROLLER:
613 /* Yes, we want a DNS */
617 load_interfaces(task, lpcfg_interfaces(task->lp_ctx), &ifaces);
619 if (iface_count(ifaces) == 0) {
620 task_server_terminate(task, "dns: no network interfaces configured", false);
624 task_server_set_title(task, "task[dns]");
626 dns = talloc_zero(task, struct dns_server);
628 task_server_terminate(task, "dns: out of memory", true);
634 dns->samdb = samdb_connect(dns, dns->task->event_ctx, dns->task->lp_ctx,
635 system_session(dns->task->lp_ctx), 0);
637 task_server_terminate(task, "dns: samdb_connect failed", true);
641 rootdn = ldb_dn_new(dns, dns->samdb, "");
642 if (rootdn == NULL) {
643 task_server_terminate(task, "dns: out of memory", true);
647 // TODO: this search does not work against windows
648 ret = dsdb_search(dns->samdb, dns, &res, rootdn, LDB_SCOPE_SUBTREE,
649 attrs, DSDB_SEARCH_SEARCH_ALL_PARTITIONS, "(objectClass=dnsZone)");
650 if (ret != LDB_SUCCESS) {
651 task_server_terminate(task,
652 "dns: failed to look up root DNS zones",
657 TYPESAFE_QSORT(res->msgs, res->count, dns_server_sort_zones);
659 for (i=0; i < res->count; i++) {
660 struct dns_server_zone *z;
662 z = talloc_zero(dns, struct dns_server_zone);
666 z->name = ldb_msg_find_attr_as_string(res->msgs[i], "name", NULL);
667 z->dn = talloc_move(z, &res->msgs[i]->dn);
669 DLIST_ADD_END(dns->zones, z, NULL);
672 status = dns_startup_interfaces(dns, task->lp_ctx, ifaces);
673 if (!NT_STATUS_IS_OK(status)) {
674 task_server_terminate(task, "dns failed to setup interfaces", true);
679 NTSTATUS server_service_dns_init(void)
681 return register_server_service("dns", dns_task_init);