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s4 dns: Map between NTSTATUS and dns error codes
[Samba/gebeck_regimport.git] / source4 / dns_server / dns_server.c
blobfc759a48326d08ca9863ea509de1e9f5fee22850
1 /*
2 Unix SMB/CIFS implementation.
3
4 DNS server startup
5
6 Copyright (C) 2010 Kai Blin <kai@samba.org>
7
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.
12
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.
17
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/>.
20 */
21
22 #include "includes.h"
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"
40 #include <ldb.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
46 /* hold information about one dns socket */
47 struct dns_socket {
48 struct dns_server *dns;
49 struct tsocket_address *local_address;
50 };
51
52 struct dns_udp_socket {
53 struct dns_socket *dns_socket;
54 struct tdgram_context *dgram;
55 struct tevent_queue *send_queue;
56 };
57
58 /*
59 state of an open tcp connection
60 */
61 struct dns_tcp_connection {
62 /* stream connection we belong to */
63 struct stream_connection *conn;
64
65 /* the dns_server the connection belongs to */
66 struct dns_socket *dns_socket;
67
68 struct tstream_context *tstream;
69
70 struct tevent_queue *send_queue;
71 };
72
73 static void dns_tcp_terminate_connection(struct dns_tcp_connection *dnsconn, const char *reason)
74 {
75 stream_terminate_connection(dnsconn->conn, reason);
76 }
77
78 static void dns_tcp_recv(struct stream_connection *conn, uint16_t flags)
79 {
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");
84 }
85
86 static void dns_tcp_send(struct stream_connection *conn, uint16_t flags)
87 {
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");
92 }
93
94 static NTSTATUS dns_err_to_ntstatus(enum dns_rcode rcode)
95 {
96 switch (rcode) {
97 case DNS_RCODE_OK: return NT_STATUS_OK;
98 case DNS_RCODE_FORMERR: return NT_STATUS_INVALID_PARAMETER;
99 case DNS_RCODE_SERVFAIL: return NT_STATUS_INTERNAL_ERROR;
100 case DNS_RCODE_NXDOMAIN: return NT_STATUS_OBJECT_NAME_NOT_FOUND;
101 case DNS_RCODE_NOTIMP: return NT_STATUS_NOT_IMPLEMENTED;
102 case DNS_RCODE_REFUSED: return NT_STATUS_ACCESS_DENIED;
103 case DNS_RCODE_NOTAUTH: return NT_STATUS_FOOBAR;
104 default: return NT_STATUS_NONE_MAPPED;
105 }
106 }
107
108 static uint8_t ntstatus_to_dns_err(NTSTATUS status)
109 {
110 if (NT_STATUS_EQUAL(NT_STATUS_OK, status)) {
111 return DNS_RCODE_OK;
112 } else if (NT_STATUS_EQUAL(NT_STATUS_INVALID_PARAMETER, status)) {
113 return DNS_RCODE_FORMERR;
114 } else if (NT_STATUS_EQUAL(NT_STATUS_INTERNAL_ERROR, status)) {
115 return DNS_RCODE_SERVFAIL;
116 } else if (NT_STATUS_EQUAL(NT_STATUS_OBJECT_NAME_NOT_FOUND, status)) {
117 return DNS_RCODE_NXDOMAIN;
118 } else if (NT_STATUS_EQUAL(NT_STATUS_NOT_IMPLEMENTED, status)) {
119 return DNS_RCODE_NOTIMP;
120 } else if (NT_STATUS_EQUAL(NT_STATUS_ACCESS_DENIED, status)) {
121 return DNS_RCODE_REFUSED;
122 } else if (NT_STATUS_EQUAL(NT_STATUS_FOOBAR, status)) {
123 return DNS_RCODE_NOTAUTH;
124 }
125 DEBUG(0, ("No mapping exists for %s\n", nt_errstr(status)));
126 }
127
128 static bool dns_name_match(const char *zone, const char *name, size_t *host_part_len)
129 {
130 size_t zl = strlen(zone);
131 size_t nl = strlen(name);
132 ssize_t zi, ni;
133 static const size_t fixup = 'a' - 'A';
134
135 if (zl > nl) {
136 return false;
137 }
138
139 for (zi = zl, ni = nl; zi >= 0; zi--, ni--) {
140 char zc = zone[zi];
141 char nc = name[ni];
142
143 /* convert to lower case */
144 if (zc >= 'A' && zc <= 'Z') {
145 zc += fixup;
146 }
147 if (nc >= 'A' && nc <= 'Z') {
148 nc += fixup;
149 }
150
151 if (zc != nc) {
152 return false;
153 }
154 }
155
156 if (ni >= 0) {
157 if (name[ni] != '.') {
158 return false;
159 }
160
161 ni--;
162 }
163
164 *host_part_len = ni+1;
165
166 return true;
167 }
168
169 static NTSTATUS dns_name2dn(struct dns_server *dns,
170 TALLOC_CTX *mem_ctx,
171 const char *name,
172 struct ldb_dn **_dn)
173 {
174 struct ldb_dn *base;
175 struct ldb_dn *dn;
176 const struct dns_server_zone *z;
177 size_t host_part_len = 0;
178
179 if (name == NULL) {
180 return NT_STATUS_INVALID_PARAMETER;
181 }
182
183 /*TODO: Check if 'name' is a valid DNS name */
184
185 if (strcmp(name, "") == 0) {
186 base = ldb_get_default_basedn(dns->samdb);
187 dn = ldb_dn_copy(mem_ctx, base);
188 ldb_dn_add_child_fmt(dn, "DC=@,DC=RootDNSServers,CN=MicrosoftDNS,CN=System");
189 *_dn = dn;
190 return NT_STATUS_OK;
191 }
192
193 for (z = dns->zones; z != NULL; z = z->next) {
194 bool match;
195
196 match = dns_name_match(z->name, name, &host_part_len);
197 if (match) {
198 break;
199 }
200 }
201
202 if (z == NULL) {
203 return NT_STATUS_OBJECT_NAME_NOT_FOUND;
204 }
205
206 if (host_part_len == 0) {
207 dn = ldb_dn_copy(mem_ctx, z->dn);
208 ldb_dn_add_child_fmt(dn, "DC=@");
209 *_dn = dn;
210 return NT_STATUS_OK;
211 }
212
213 dn = ldb_dn_copy(mem_ctx, z->dn);
214 ldb_dn_add_child_fmt(dn, "DC=%*.*s", (int)host_part_len, (int)host_part_len, name);
215 *_dn = dn;
216 return NT_STATUS_OK;
217 }
218
219 static NTSTATUS handle_question(struct dns_server *dns,
220 TALLOC_CTX *mem_ctx,
221 const struct dns_name_question *question,
222 struct dns_res_rec **answers, uint16_t *ancount)
223 {
224 struct dns_res_rec *ans;
225 struct ldb_dn *dn = NULL;
226 NTSTATUS status;
227 static const char * const attrs[] = { "dnsRecord", NULL};
228 int ret;
229 uint16_t ai = *ancount;
230 uint16_t ri;
231 struct ldb_message *msg = NULL;
232 struct dnsp_DnssrvRpcRecord *recs;
233 struct ldb_message_element *el;
234
235 status = dns_name2dn(dns, mem_ctx, question->name, &dn);
236 NT_STATUS_NOT_OK_RETURN(status);
237
238 ret = dsdb_search_one(dns->samdb, mem_ctx, &msg, dn,
239 LDB_SCOPE_BASE, attrs, 0, "%s", "(objectClass=dnsNode)");
240 if (ret != LDB_SUCCESS) {
241 return NT_STATUS_OBJECT_NAME_NOT_FOUND;
242 }
243
244 el = ldb_msg_find_element(msg, attrs[0]);
245 if (el == NULL) {
246 return NT_STATUS_OBJECT_NAME_NOT_FOUND;
247 }
248
249 recs = talloc_array(mem_ctx, struct dnsp_DnssrvRpcRecord, el->num_values);
250 for (ri = 0; ri < el->num_values; ri++) {
251 struct ldb_val *v = &el->values[ri];
252 enum ndr_err_code ndr_err;
253
254 ndr_err = ndr_pull_struct_blob(v, recs, &recs[ri],
255 (ndr_pull_flags_fn_t)ndr_pull_dnsp_DnssrvRpcRecord);
256 if (!NDR_ERR_CODE_IS_SUCCESS(ndr_err)) {
257 DEBUG(0, ("Failed to grab dnsp_DnssrvRpcRecord\n"));
258 return NT_STATUS_INTERNAL_DB_CORRUPTION;
259 }
260 }
261
262 ans = talloc_realloc(mem_ctx, *answers, struct dns_res_rec,
263 ai + el->num_values);
264 NT_STATUS_HAVE_NO_MEMORY(ans);
265
266 switch (question->question_type) {
267 case DNS_QTYPE_CNAME:
268 for (ri = 0; ri < el->num_values; ri++) {
269 if (recs[ri].wType != question->question_type) {
270 continue;
271 }
272
273 ZERO_STRUCT(ans[ai]);
274 ans[ai].name = talloc_strdup(ans, question->name);
275 ans[ai].rr_type = DNS_QTYPE_CNAME;
276 ans[ai].rr_class = DNS_QCLASS_IP;
277 ans[ai].ttl = recs[ri].dwTtlSeconds;
278 ans[ai].length = UINT16_MAX;
279 ans[ai].rdata.cname_record = talloc_strdup(ans, recs[ri].data.cname);
280 ai++;
281 }
282 break;
283 case DNS_QTYPE_A:
284 for (ri = 0; ri < el->num_values; ri++) {
285 if (recs[ri].wType != question->question_type) {
286 continue;
287 }
288
289 ZERO_STRUCT(ans[ai]);
290 ans[ai].name = talloc_strdup(ans, question->name);
291 ans[ai].rr_type = DNS_QTYPE_A;
292 ans[ai].rr_class = DNS_QCLASS_IP;
293 ans[ai].ttl = recs[ri].dwTtlSeconds;
294 ans[ai].length = UINT16_MAX;
295 ans[ai].rdata.ipv4_record = talloc_strdup(ans, recs[ri].data.ipv4);
296 ai++;
297 }
298 break;
299 case DNS_QTYPE_AAAA:
300 for (ri = 0; ri < el->num_values; ri++) {
301 if (recs[ri].wType != question->question_type) {
302 continue;
303 }
304
305 ZERO_STRUCT(ans[ai]);
306 ans[ai].name = talloc_strdup(ans, question->name);
307 ans[ai].rr_type = DNS_QTYPE_AAAA;
308 ans[ai].rr_class = DNS_QCLASS_IP;
309 ans[ai].ttl = recs[ri].dwTtlSeconds;
310 ans[ai].length = UINT16_MAX;
311 ans[ai].rdata.ipv6_record = recs[ri].data.ipv6;
312 ai++;
313 }
314 break;
315 case DNS_QTYPE_NS:
316 for (ri = 0; ri < el->num_values; ri++) {
317 if (recs[ri].wType != question->question_type) {
318 continue;
319 }
320
321 ZERO_STRUCT(ans[ai]);
322 ans[ai].name = question->name;
323 ans[ai].rr_type = DNS_QTYPE_NS;
324 ans[ai].rr_class = DNS_QCLASS_IP;
325 ans[ai].ttl = recs[ri].dwTtlSeconds;
326 ans[ai].length = UINT16_MAX;
327 ans[ai].rdata.ns_record = recs[ri].data.ns;
328 ai++;
329 }
330 break;
331 case DNS_QTYPE_SRV:
332 for (ri = 0; ri < el->num_values; ri++) {
333 if (recs[ri].wType != question->question_type) {
334 continue;
335 }
336
337 ZERO_STRUCT(ans[ai]);
338 ans[ai].name = question->name;
339 ans[ai].rr_type = DNS_QTYPE_SRV;
340 ans[ai].rr_class = DNS_QCLASS_IP;
341 ans[ai].ttl = recs[ri].dwTtlSeconds;
342 ans[ai].length = UINT16_MAX;
343 ans[ai].rdata.srv_record.priority = recs[ri].data.srv.wPriority;
344 ans[ai].rdata.srv_record.weight = recs[ri].data.srv.wWeight;
345 ans[ai].rdata.srv_record.port = recs[ri].data.srv.wPort;
346 ans[ai].rdata.srv_record.target = recs[ri].data.srv.nameTarget;
347 ai++;
348 }
349 break;
350 case DNS_QTYPE_SOA:
351 for (ri = 0; ri < el->num_values; ri++) {
352 if (recs[ri].wType != question->question_type) {
353 continue;
354 }
355
356 ZERO_STRUCT(ans[ai]);
357 ans[ai].name = question->name;
358 ans[ai].rr_type = DNS_QTYPE_SOA;
359 ans[ai].rr_class = DNS_QCLASS_IP;
360 ans[ai].ttl = recs[ri].dwTtlSeconds;
361 ans[ai].length = UINT16_MAX;
362 ans[ai].rdata.soa_record.mname = recs[ri].data.soa.mname;
363 ans[ai].rdata.soa_record.rname = recs[ri].data.soa.rname;
364 ans[ai].rdata.soa_record.serial = recs[ri].data.soa.serial;
365 ans[ai].rdata.soa_record.refresh= recs[ri].data.soa.refresh;
366 ans[ai].rdata.soa_record.retry = recs[ri].data.soa.retry;
367 ans[ai].rdata.soa_record.expire = recs[ri].data.soa.expire;
368 ans[ai].rdata.soa_record.minimum= recs[ri].data.soa.minimum;
369 ai++;
370 }
371 break;
372 default:
373 return NT_STATUS_NOT_IMPLEMENTED;
374 }
375
376 if (*ancount == ai) {
377 return NT_STATUS_OBJECT_NAME_NOT_FOUND;
378 }
379
380 *ancount = ai;
381 *answers = ans;
382
383 return NT_STATUS_OK;
384
385 }
386
387 static NTSTATUS dns_server_process_query(struct dns_server *dns,
388 TALLOC_CTX *mem_ctx,
389 struct dns_name_packet *in,
390 struct dns_res_rec **answers, uint16_t *ancount,
391 struct dns_res_rec **nsrecs, uint16_t *nscount,
392 struct dns_res_rec **additional, uint16_t *arcount)
393 {
394 uint16_t num_answers=0;
395 struct dns_res_rec *ans=NULL;
396 int i;
397 NTSTATUS status;
398
399 ans = talloc_array(mem_ctx, struct dns_res_rec, 0);
400 if (answers == NULL) return NT_STATUS_NO_MEMORY;
401
402 for (i = 0; i < in->qdcount; ++i) {
403 status = handle_question(dns, mem_ctx, &in->questions[i], &ans, &num_answers);
404 NT_STATUS_NOT_OK_RETURN(status);
405 }
406
407 *answers = ans;
408 *ancount = num_answers;
409
410 /*FIXME: Do something for these */
411 *nsrecs = NULL;
412 *nscount = 0;
413
414 *additional = NULL;
415 *arcount = 0;
416
417 return NT_STATUS_OK;
418 }
419
420 static NTSTATUS dns_server_process_update(struct dns_server *dns,
421 TALLOC_CTX *mem_ctx,
422 struct dns_name_packet *in,
423 struct dns_res_rec **prereqs, uint16_t *prereq_count,
424 struct dns_res_rec **updates, uint16_t *update_count,
425 struct dns_res_rec **additional, uint16_t *arcount)
426 {
427 struct dns_name_question *zone;
428
429 if (in->qdcount != 1) {
430 return NT_STATUS_NOT_IMPLEMENTED;
431 }
432
433 zone = in->questions;
434
435 DEBUG(0, ("Got a dns update request.\n"));
436
437
438 return NT_STATUS_NOT_IMPLEMENTED;
439 }
440
441 static NTSTATUS dns_process(struct dns_server *dns,
442 TALLOC_CTX *mem_ctx,
443 DATA_BLOB *in,
444 DATA_BLOB *out)
445 {
446 enum ndr_err_code ndr_err;
447 NTSTATUS ret;
448 struct dns_name_packet *in_packet;
449 struct dns_name_packet *out_packet;
450 struct dns_res_rec *answers = NULL, *nsrecs = NULL, *additional = NULL;
451 uint16_t num_answers = 0 , num_nsrecs = 0, num_additional = 0;
452 uint16_t reply_code;
453
454 if (in->length < 12) {
455 return NT_STATUS_INVALID_PARAMETER;
456 }
457
458 in_packet = talloc_zero(mem_ctx, struct dns_name_packet);
459 /* TODO: We don't really need an out_packet. */
460 out_packet = talloc_zero(mem_ctx, struct dns_name_packet);
461
462 if (in_packet == NULL) return NT_STATUS_NO_MEMORY;
463 if (out_packet == NULL) return NT_STATUS_NO_MEMORY;
464
465 dump_data(2, in->data, in->length);
466
467 ndr_err = ndr_pull_struct_blob(in, in_packet, in_packet,
468 (ndr_pull_flags_fn_t)ndr_pull_dns_name_packet);
469 if (!NDR_ERR_CODE_IS_SUCCESS(ndr_err)) {
470 TALLOC_FREE(in_packet);
471 DEBUG(0, ("Failed to parse packet %d!\n", ndr_err));
472 *out = *in;
473
474 out->data[2] |= 0x80; /* Toggle DNS_FLAG_REPLY */
475 out->data[3] |= DNS_RCODE_FORMERR;
476
477 return NT_STATUS_OK;
478 }
479
480 NDR_PRINT_DEBUG(dns_name_packet, in_packet);
481 *out_packet = *in_packet;
482 out_packet->operation |= DNS_FLAG_REPLY;
483
484 switch (in_packet->operation & DNS_OPCODE) {
485 case DNS_OPCODE_QUERY:
486
487 ret = dns_server_process_query(dns, out_packet, in_packet,
488 &answers, &num_answers,
489 &nsrecs, &num_nsrecs,
490 &additional, &num_additional);
491 reply_code = DNS_RCODE_NXDOMAIN;
492
493 break;
494 case DNS_OPCODE_REGISTER:
495 ret = dns_server_process_update(dns, out_packet, in_packet,
496 &answers, &num_answers,
497 &nsrecs, &num_nsrecs,
498 &additional, &num_additional);
499 reply_code = ntstatus_to_dns_err(ret);
500 break;
501 default:
502 ret = NT_STATUS_NOT_IMPLEMENTED;
503 reply_code = DNS_RCODE_NOTIMP;
504 break;
505 }
506
507 if (NT_STATUS_IS_OK(ret)) {
508 out_packet->ancount = num_answers;
509 out_packet->answers = answers;
510
511 out_packet->nscount = num_nsrecs;
512 out_packet->nsrecs = nsrecs;
513
514 out_packet->arcount = num_additional;
515 out_packet->additional = additional;
516 } else {
517 out_packet->operation |= reply_code;
518 }
519
520 NDR_PRINT_DEBUG(dns_name_packet, out_packet);
521 ndr_err = ndr_push_struct_blob(out, out_packet, out_packet,
522 (ndr_push_flags_fn_t)ndr_push_dns_name_packet);
523 if (!NDR_ERR_CODE_IS_SUCCESS(ndr_err)) {
524 TALLOC_FREE(in_packet);
525 TALLOC_FREE(out_packet);
526 DEBUG(0, ("Failed to push packet %d!\n", ndr_err));
527 *out = *in;
528
529 out->data[2] |= 0x80; /* Toggle DNS_FLAG_REPLY */
530 out->data[3] |= DNS_RCODE_SERVFAIL;
531
532 return NT_STATUS_OK;
533 }
534
535 dump_data(2, out->data, out->length);
536 return NT_STATUS_OK;
537 }
538
539 struct dns_tcp_call {
540 struct dns_tcp_connection *dns_conn;
541 DATA_BLOB in;
542 DATA_BLOB out;
543 uint8_t out_hdr[4];
544 struct iovec out_iov[2];
545 };
546
547 static void dns_tcp_call_writev_done(struct tevent_req *subreq);
548
549 static void dns_tcp_call_loop(struct tevent_req *subreq)
550 {
551 struct dns_tcp_connection *dns_conn = tevent_req_callback_data(subreq,
552 struct dns_tcp_connection);
553 struct dns_tcp_call *call;
554 NTSTATUS status;
555
556 call = talloc(dns_conn, struct dns_tcp_call);
557 if (call == NULL) {
558 dns_tcp_terminate_connection(dns_conn, "dns_tcp_call_loop: "
559 "no memory for dns_tcp_call");
560 return;
561 }
562 call->dns_conn = dns_conn;
563
564 status = tstream_read_pdu_blob_recv(subreq,
565 call,
566 &call->in);
567 TALLOC_FREE(subreq);
568 if (!NT_STATUS_IS_OK(status)) {
569 const char *reason;
570
571 reason = talloc_asprintf(call, "dns_tcp_call_loop: "
572 "tstream_read_pdu_blob_recv() - %s",
573 nt_errstr(status));
574 if (!reason) {
575 reason = nt_errstr(status);
576 }
577
578 dns_tcp_terminate_connection(dns_conn, reason);
579 return;
580 }
581
582 DEBUG(10,("Received krb5 TCP packet of length %lu from %s\n",
583 (long) call->in.length,
584 tsocket_address_string(dns_conn->conn->remote_address, call)));
585
586 /* skip length header */
587 call->in.data +=4;
588 call->in.length -= 4;
589
590 /* Call dns */
591 status = dns_process(dns_conn->dns_socket->dns, call, &call->in, &call->out);
592 if (!NT_STATUS_IS_OK(status)) {
593 DEBUG(0, ("dns_process returned %s\n", nt_errstr(status)));
594 dns_tcp_terminate_connection(dns_conn,
595 "dns_tcp_call_loop: process function failed");
596 return;
597 }
598
599 /* First add the length of the out buffer */
600 RSIVAL(call->out_hdr, 0, call->out.length);
601 call->out_iov[0].iov_base = (char *) call->out_hdr;
602 call->out_iov[0].iov_len = 4;
603
604 call->out_iov[1].iov_base = (char *) call->out.data;
605 call->out_iov[1].iov_len = call->out.length;
606
607 subreq = tstream_writev_queue_send(call,
608 dns_conn->conn->event.ctx,
609 dns_conn->tstream,
610 dns_conn->send_queue,
611 call->out_iov, 2);
612 if (subreq == NULL) {
613 dns_tcp_terminate_connection(dns_conn, "dns_tcp_call_loop: "
614 "no memory for tstream_writev_queue_send");
615 return;
616 }
617 tevent_req_set_callback(subreq, dns_tcp_call_writev_done, call);
618
619 /*
620 * The krb5 tcp pdu's has the length as 4 byte (initial_read_size),
621 * packet_full_request_u32 provides the pdu length then.
622 */
623 subreq = tstream_read_pdu_blob_send(dns_conn,
624 dns_conn->conn->event.ctx,
625 dns_conn->tstream,
626 4, /* initial_read_size */
627 packet_full_request_u32,
628 dns_conn);
629 if (subreq == NULL) {
630 dns_tcp_terminate_connection(dns_conn, "dns_tcp_call_loop: "
631 "no memory for tstream_read_pdu_blob_send");
632 return;
633 }
634 tevent_req_set_callback(subreq, dns_tcp_call_loop, dns_conn);
635 }
636
637 static void dns_tcp_call_writev_done(struct tevent_req *subreq)
638 {
639 struct dns_tcp_call *call = tevent_req_callback_data(subreq,
640 struct dns_tcp_call);
641 int sys_errno;
642 int rc;
643
644 rc = tstream_writev_queue_recv(subreq, &sys_errno);
645 TALLOC_FREE(subreq);
646 if (rc == -1) {
647 const char *reason;
648
649 reason = talloc_asprintf(call, "dns_tcp_call_writev_done: "
650 "tstream_writev_queue_recv() - %d:%s",
651 sys_errno, strerror(sys_errno));
652 if (!reason) {
653 reason = "dns_tcp_call_writev_done: tstream_writev_queue_recv() failed";
654 }
655
656 dns_tcp_terminate_connection(call->dns_conn, reason);
657 return;
658 }
659
660 /* We don't care about errors */
661
662 talloc_free(call);
663 }
664
665 /*
666 called when we get a new connection
667 */
668 static void dns_tcp_accept(struct stream_connection *conn)
669 {
670 struct dns_socket *dns_socket;
671 struct dns_tcp_connection *dns_conn;
672 struct tevent_req *subreq;
673 int rc;
674
675 dns_conn = talloc_zero(conn, struct dns_tcp_connection);
676 if (dns_conn == NULL) {
677 stream_terminate_connection(conn,
678 "dns_tcp_accept: out of memory");
679 return;
680 }
681
682 dns_conn->send_queue = tevent_queue_create(conn, "dns_tcp_accept");
683 if (dns_conn->send_queue == NULL) {
684 stream_terminate_connection(conn,
685 "dns_tcp_accept: out of memory");
686 return;
687 }
688
689 dns_socket = talloc_get_type(conn->private_data, struct dns_socket);
690
691 TALLOC_FREE(conn->event.fde);
692
693 rc = tstream_bsd_existing_socket(dns_conn,
694 socket_get_fd(conn->socket),
695 &dns_conn->tstream);
696 if (rc < 0) {
697 stream_terminate_connection(conn,
698 "dns_tcp_accept: out of memory");
699 return;
700 }
701
702 dns_conn->conn = conn;
703 dns_conn->dns_socket = dns_socket;
704 conn->private_data = dns_conn;
705
706 /*
707 * The krb5 tcp pdu's has the length as 4 byte (initial_read_size),
708 * packet_full_request_u32 provides the pdu length then.
709 */
710 subreq = tstream_read_pdu_blob_send(dns_conn,
711 dns_conn->conn->event.ctx,
712 dns_conn->tstream,
713 4, /* initial_read_size */
714 packet_full_request_u32,
715 dns_conn);
716 if (subreq == NULL) {
717 dns_tcp_terminate_connection(dns_conn, "dns_tcp_accept: "
718 "no memory for tstream_read_pdu_blob_send");
719 return;
720 }
721 tevent_req_set_callback(subreq, dns_tcp_call_loop, dns_conn);
722 }
723
724 static const struct stream_server_ops dns_tcp_stream_ops = {
725 .name = "dns_tcp",
726 .accept_connection = dns_tcp_accept,
727 .recv_handler = dns_tcp_recv,
728 .send_handler = dns_tcp_send
729 };
730
731 struct dns_udp_call {
732 struct tsocket_address *src;
733 DATA_BLOB in;
734 DATA_BLOB out;
735 };
736
737 static void dns_udp_call_sendto_done(struct tevent_req *subreq);
738
739 static void dns_udp_call_loop(struct tevent_req *subreq)
740 {
741 struct dns_udp_socket *sock = tevent_req_callback_data(subreq,
742 struct dns_udp_socket);
743 struct dns_udp_call *call;
744 uint8_t *buf;
745 ssize_t len;
746 int sys_errno;
747 NTSTATUS status;
748
749 call = talloc(sock, struct dns_udp_call);
750 if (call == NULL) {
751 talloc_free(call);
752 goto done;
753 }
754
755 len = tdgram_recvfrom_recv(subreq, &sys_errno,
756 call, &buf, &call->src);
757 TALLOC_FREE(subreq);
758 if (len == -1) {
759 talloc_free(call);
760 goto done;
761 }
762
763 call->in.data = buf;
764 call->in.length = len;
765
766 DEBUG(10,("Received krb5 UDP packet of length %lu from %s\n",
767 (long)call->in.length,
768 tsocket_address_string(call->src, call)));
769
770 /* Call krb5 */
771 status = dns_process(sock->dns_socket->dns, call, &call->in, &call->out);
772 if (!NT_STATUS_IS_OK(status)) {
773 talloc_free(call);
774 DEBUG(0, ("dns_process returned %s\n", nt_errstr(status)));
775 goto done;
776 }
777
778 subreq = tdgram_sendto_queue_send(call,
779 sock->dns_socket->dns->task->event_ctx,
780 sock->dgram,
781 sock->send_queue,
782 call->out.data,
783 call->out.length,
784 call->src);
785 if (subreq == NULL) {
786 talloc_free(call);
787 goto done;
788 }
789 tevent_req_set_callback(subreq, dns_udp_call_sendto_done, call);
790
791 done:
792 subreq = tdgram_recvfrom_send(sock,
793 sock->dns_socket->dns->task->event_ctx,
794 sock->dgram);
795 if (subreq == NULL) {
796 task_server_terminate(sock->dns_socket->dns->task,
797 "no memory for tdgram_recvfrom_send",
798 true);
799 return;
800 }
801 tevent_req_set_callback(subreq, dns_udp_call_loop, sock);
802 }
803
804 static void dns_udp_call_sendto_done(struct tevent_req *subreq)
805 {
806 struct dns_udp_call *call = tevent_req_callback_data(subreq,
807 struct dns_udp_call);
808 ssize_t ret;
809 int sys_errno;
810
811 ret = tdgram_sendto_queue_recv(subreq, &sys_errno);
812
813 /* We don't care about errors */
814
815 talloc_free(call);
816 }
817
818 /*
819 start listening on the given address
820 */
821 static NTSTATUS dns_add_socket(struct dns_server *dns,
822 const struct model_ops *model_ops,
823 const char *name,
824 const char *address,
825 uint16_t port)
826 {
827 struct dns_socket *dns_socket;
828 struct dns_udp_socket *dns_udp_socket;
829 struct tevent_req *udpsubreq;
830 NTSTATUS status;
831 int ret;
832
833 dns_socket = talloc(dns, struct dns_socket);
834 NT_STATUS_HAVE_NO_MEMORY(dns_socket);
835
836 dns_socket->dns = dns;
837
838 ret = tsocket_address_inet_from_strings(dns_socket, "ip",
839 address, port,
840 &dns_socket->local_address);
841 if (ret != 0) {
842 status = map_nt_error_from_unix(errno);
843 return status;
844 }
845
846 status = stream_setup_socket(dns->task->event_ctx,
847 dns->task->lp_ctx,
848 model_ops,
849 &dns_tcp_stream_ops,
850 "ip", address, &port,
851 lpcfg_socket_options(dns->task->lp_ctx),
852 dns_socket);
853 if (!NT_STATUS_IS_OK(status)) {
854 DEBUG(0,("Failed to bind to %s:%u TCP - %s\n",
855 address, port, nt_errstr(status)));
856 talloc_free(dns_socket);
857 return status;
858 }
859
860 dns_udp_socket = talloc(dns_socket, struct dns_udp_socket);
861 NT_STATUS_HAVE_NO_MEMORY(dns_udp_socket);
862
863 dns_udp_socket->dns_socket = dns_socket;
864
865 ret = tdgram_inet_udp_socket(dns_socket->local_address,
866 NULL,
867 dns_udp_socket,
868 &dns_udp_socket->dgram);
869 if (ret != 0) {
870 status = map_nt_error_from_unix(errno);
871 DEBUG(0,("Failed to bind to %s:%u UDP - %s\n",
872 address, port, nt_errstr(status)));
873 return status;
874 }
875
876 dns_udp_socket->send_queue = tevent_queue_create(dns_udp_socket,
877 "dns_udp_send_queue");
878 NT_STATUS_HAVE_NO_MEMORY(dns_udp_socket->send_queue);
879
880 udpsubreq = tdgram_recvfrom_send(dns_udp_socket,
881 dns->task->event_ctx,
882 dns_udp_socket->dgram);
883 NT_STATUS_HAVE_NO_MEMORY(udpsubreq);
884 tevent_req_set_callback(udpsubreq, dns_udp_call_loop, dns_udp_socket);
885
886 return NT_STATUS_OK;
887 }
888
889 /*
890 setup our listening sockets on the configured network interfaces
891 */
892 static NTSTATUS dns_startup_interfaces(struct dns_server *dns, struct loadparm_context *lp_ctx,
893 struct interface *ifaces)
894 {
895 const struct model_ops *model_ops;
896 int num_interfaces;
897 TALLOC_CTX *tmp_ctx = talloc_new(dns);
898 NTSTATUS status;
899 int i;
900
901 /* within the dns task we want to be a single process, so
902 ask for the single process model ops and pass these to the
903 stream_setup_socket() call. */
904 model_ops = process_model_startup(dns->task->event_ctx, "single");
905 if (!model_ops) {
906 DEBUG(0,("Can't find 'single' process model_ops\n"));
907 return NT_STATUS_INTERNAL_ERROR;
908 }
909
910 num_interfaces = iface_count(ifaces);
911
912 for (i=0; i<num_interfaces; i++) {
913 const char *address = talloc_strdup(tmp_ctx, iface_n_ip(ifaces, i));
914
915 status = dns_add_socket(dns, model_ops, "dns", address, DNS_SERVICE_PORT);
916 NT_STATUS_NOT_OK_RETURN(status);
917 }
918
919 talloc_free(tmp_ctx);
920
921 return NT_STATUS_OK;
922 }
923
924 static int dns_server_sort_zones(struct ldb_message **m1, struct ldb_message **m2)
925 {
926 const char *n1, *n2;
927 size_t l1, l2;
928
929 n1 = ldb_msg_find_attr_as_string(*m1, "name", NULL);
930 n2 = ldb_msg_find_attr_as_string(*m2, "name", NULL);
931
932 l1 = strlen(n1);
933 l2 = strlen(n2);
934
935 /* If the string lengths are not equal just sort by length */
936 if (l1 != l2) {
937 /* If m1 is the larger zone name, return it first */
938 return l2 - l1;
939 }
940
941 /*TODO: We need to compare DNs here, we want the DomainDNSZones first */
942 return 0;
943 }
944
945 static void dns_task_init(struct task_server *task)
946 {
947 struct dns_server *dns;
948 NTSTATUS status;
949 struct interface *ifaces;
950 int ret;
951 struct ldb_result *res;
952 struct ldb_dn *rootdn;
953 static const char * const attrs[] = { "name", NULL};
954 int i;
955
956
957 switch (lpcfg_server_role(task->lp_ctx)) {
958 case ROLE_STANDALONE:
959 task_server_terminate(task, "dns: no DNS required in standalone configuration", false);
960 return;
961 case ROLE_DOMAIN_MEMBER:
962 task_server_terminate(task, "dns: no DNS required in member server configuration", false);
963 return;
964 case ROLE_DOMAIN_CONTROLLER:
965 /* Yes, we want a DNS */
966 break;
967 }
968
969 load_interfaces(task, lpcfg_interfaces(task->lp_ctx), &ifaces);
970
971 if (iface_count(ifaces) == 0) {
972 task_server_terminate(task, "dns: no network interfaces configured", false);
973 return;
974 }
975
976 task_server_set_title(task, "task[dns]");
977
978 dns = talloc_zero(task, struct dns_server);
979 if (dns == NULL) {
980 task_server_terminate(task, "dns: out of memory", true);
981 return;
982 }
983
984 dns->task = task;
985
986 dns->samdb = samdb_connect(dns, dns->task->event_ctx, dns->task->lp_ctx,
987 system_session(dns->task->lp_ctx), 0);
988 if (!dns->samdb) {
989 task_server_terminate(task, "dns: samdb_connect failed", true);
990 return;
991 }
992
993 rootdn = ldb_dn_new(dns, dns->samdb, "");
994 if (rootdn == NULL) {
995 task_server_terminate(task, "dns: out of memory", true);
996 return;
997 }
998
999 // TODO: this search does not work against windows
1000 ret = dsdb_search(dns->samdb, dns, &res, rootdn, LDB_SCOPE_SUBTREE,
1001 attrs, DSDB_SEARCH_SEARCH_ALL_PARTITIONS, "(objectClass=dnsZone)");
1002 if (ret != LDB_SUCCESS) {
1003 task_server_terminate(task,
1004 "dns: failed to look up root DNS zones",
1005 true);
1006 return;
1007 }
1008
1009 TYPESAFE_QSORT(res->msgs, res->count, dns_server_sort_zones);
1010
1011 for (i=0; i < res->count; i++) {
1012 struct dns_server_zone *z;
1013
1014 z = talloc_zero(dns, struct dns_server_zone);
1015 if (z == NULL) {
1016 }
1017
1018 z->name = ldb_msg_find_attr_as_string(res->msgs[i], "name", NULL);
1019 z->dn = talloc_move(z, &res->msgs[i]->dn);
1020
1021 DLIST_ADD_END(dns->zones, z, NULL);
1022 }
1023
1024 status = dns_startup_interfaces(dns, task->lp_ctx, ifaces);
1025 if (!NT_STATUS_IS_OK(status)) {
1026 task_server_terminate(task, "dns failed to setup interfaces", true);
1027 return;
1028 }
1029 }
1030
1031 NTSTATUS server_service_dns_init(void)
1032 {
1033 return register_server_service("dns", dns_task_init);
1034 }
reg import