source4/dns_server/dns_server.c

   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 NTSTATUS server_service_dns_init(void);
  47
  48 /* hold information about one dns socket */
  49 struct dns_socket {
  50         struct dns_server *dns;
  51         struct tsocket_address *local_address;
  52 };
  53
  54 struct dns_udp_socket {
  55         struct dns_socket *dns_socket;
  56         struct tdgram_context *dgram;
  57         struct tevent_queue *send_queue;
  58 };
  59
  60 /*
  61   state of an open tcp connection
  62 */
  63 struct dns_tcp_connection {
  64         /* stream connection we belong to */
  65         struct stream_connection *conn;
  66
  67         /* the dns_server the connection belongs to */
  68         struct dns_socket *dns_socket;
  69
  70         struct tstream_context *tstream;
  71
  72         struct tevent_queue *send_queue;
  73 };
  74
  75 static void dns_tcp_terminate_connection(struct dns_tcp_connection *dnsconn, const char *reason)
  76 {
  77         stream_terminate_connection(dnsconn->conn, reason);
  78 }
  79
  80 static void dns_tcp_recv(struct stream_connection *conn, uint16_t flags)
  81 {
  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");
  86 }
  87
  88 static void dns_tcp_send(struct stream_connection *conn, uint16_t flags)
  89 {
  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");
  94 }
  95
  96 static NTSTATUS dns_process(struct dns_server *dns,
  97                             TALLOC_CTX *mem_ctx,
  98                             DATA_BLOB *in,
  99                             DATA_BLOB *out)
 100 {
 101         enum ndr_err_code ndr_err;
 102         WERROR ret;
 103         struct dns_name_packet *in_packet;
 104         struct dns_name_packet *out_packet;
 105         struct dns_res_rec *answers = NULL, *nsrecs = NULL, *additional = NULL;
 106         uint16_t num_answers = 0 , num_nsrecs = 0, num_additional = 0;
 107
 108         if (in->length < 12) {
 109                 return NT_STATUS_INVALID_PARAMETER;
 110         }
 111
 112         in_packet = talloc_zero(mem_ctx, struct dns_name_packet);
 113         /* TODO: We don't really need an out_packet. */
 114         out_packet = talloc_zero(mem_ctx, struct dns_name_packet);
 115
 116         if (in_packet == NULL) return NT_STATUS_NO_MEMORY;
 117         if (out_packet == NULL) return NT_STATUS_NO_MEMORY;
 118
 119         dump_data(2, in->data, in->length);
 120
 121         ndr_err = ndr_pull_struct_blob(in, in_packet, in_packet,
 122                         (ndr_pull_flags_fn_t)ndr_pull_dns_name_packet);
 123         if (!NDR_ERR_CODE_IS_SUCCESS(ndr_err)) {
 124                 TALLOC_FREE(in_packet);
 125                 DEBUG(0, ("Failed to parse packet %d!\n", ndr_err));
 126                 *out = *in;
 127
 128                 out->data[2] |= 0x80; /* Toggle DNS_FLAG_REPLY */
 129                 out->data[3] |= DNS_RCODE_FORMERR;
 130
 131                 return NT_STATUS_OK;
 132         }
 133         if (DEBUGLVL(2)) {
 134                 NDR_PRINT_DEBUG(dns_name_packet, in_packet);
 135         }
 136         *out_packet = *in_packet;
 137         out_packet->operation |= DNS_FLAG_REPLY;
 138
 139         switch (in_packet->operation & DNS_OPCODE) {
 140         case DNS_OPCODE_QUERY:
 141
 142                 ret = dns_server_process_query(dns, out_packet, in_packet,
 143                                                &answers, &num_answers,
 144                                                &nsrecs,  &num_nsrecs,
 145                                                &additional, &num_additional);
 146
 147                 break;
 148         case DNS_OPCODE_UPDATE:
 149                 ret = dns_server_process_update(dns, out_packet, in_packet,
 150                                                 &answers, &num_answers,
 151                                                 &nsrecs,  &num_nsrecs,
 152                                                 &additional, &num_additional);
 153                 break;
 154         default:
 155                 ret = WERR_DNS_ERROR_RCODE_NOT_IMPLEMENTED;
 156                 break;
 157         }
 158
 159         if (W_ERROR_IS_OK(ret)) {
 160                 out_packet->ancount = num_answers;
 161                 out_packet->answers = answers;
 162
 163                 out_packet->nscount = num_nsrecs;
 164                 out_packet->nsrecs  = nsrecs;
 165
 166                 out_packet->arcount = num_additional;
 167                 out_packet->additional = additional;
 168         } else {
 169                 out_packet->operation |= werr_to_dns_err(ret);
 170         }
 171
 172         if (DEBUGLVL(2)) {
 173                 NDR_PRINT_DEBUG(dns_name_packet, out_packet);
 174         }
 175         ndr_err = ndr_push_struct_blob(out, out_packet, out_packet,
 176                         (ndr_push_flags_fn_t)ndr_push_dns_name_packet);
 177         if (!NDR_ERR_CODE_IS_SUCCESS(ndr_err)) {
 178                 TALLOC_FREE(in_packet);
 179                 TALLOC_FREE(out_packet);
 180                 DEBUG(0, ("Failed to push packet %d!\n", ndr_err));
 181                 *out = *in;
 182
 183                 out->data[2] |= 0x80; /* Toggle DNS_FLAG_REPLY */
 184                 out->data[3] |= DNS_RCODE_SERVFAIL;
 185
 186                 return NT_STATUS_OK;
 187         }
 188
 189         dump_data(2, out->data, out->length);
 190         return NT_STATUS_OK;
 191 }
 192
 193 struct dns_tcp_call {
 194         struct dns_tcp_connection *dns_conn;
 195         DATA_BLOB in;
 196         DATA_BLOB out;
 197         uint8_t out_hdr[4];
 198         struct iovec out_iov[2];
 199 };
 200
 201 static void dns_tcp_call_writev_done(struct tevent_req *subreq);
 202
 203 static void dns_tcp_call_loop(struct tevent_req *subreq)
 204 {
 205         struct dns_tcp_connection *dns_conn = tevent_req_callback_data(subreq,
 206                                       struct dns_tcp_connection);
 207         struct dns_tcp_call *call;
 208         NTSTATUS status;
 209
 210         call = talloc(dns_conn, struct dns_tcp_call);
 211         if (call == NULL) {
 212                 dns_tcp_terminate_connection(dns_conn, "dns_tcp_call_loop: "
 213                                 "no memory for dns_tcp_call");
 214                 return;
 215         }
 216         call->dns_conn = dns_conn;
 217
 218         status = tstream_read_pdu_blob_recv(subreq,
 219                                             call,
 220                                             &call->in);
 221         TALLOC_FREE(subreq);
 222         if (!NT_STATUS_IS_OK(status)) {
 223                 const char *reason;
 224
 225                 reason = talloc_asprintf(call, "dns_tcp_call_loop: "
 226                                          "tstream_read_pdu_blob_recv() - %s",
 227                                          nt_errstr(status));
 228                 if (!reason) {
 229                         reason = nt_errstr(status);
 230                 }
 231
 232                 dns_tcp_terminate_connection(dns_conn, reason);
 233                 return;
 234         }
 235
 236         DEBUG(10,("Received krb5 TCP packet of length %lu from %s\n",
 237                  (long) call->in.length,
 238                  tsocket_address_string(dns_conn->conn->remote_address, call)));
 239
 240         /* skip length header */
 241         call->in.data += 4;
 242         call->in.length -= 4;
 243
 244         /* Call dns */
 245         status = dns_process(dns_conn->dns_socket->dns, call, &call->in, &call->out);
 246         if (!NT_STATUS_IS_OK(status)) {
 247                 DEBUG(0, ("dns_process returned %s\n", nt_errstr(status)));
 248                 dns_tcp_terminate_connection(dns_conn,
 249                                 "dns_tcp_call_loop: process function failed");
 250                 return;
 251         }
 252
 253         /* First add the length of the out buffer */
 254         RSIVAL(call->out_hdr, 0, call->out.length);
 255         call->out_iov[0].iov_base = (char *) call->out_hdr;
 256         call->out_iov[0].iov_len = 4;
 257
 258         call->out_iov[1].iov_base = (char *) call->out.data;
 259         call->out_iov[1].iov_len = call->out.length;
 260
 261         subreq = tstream_writev_queue_send(call,
 262                                            dns_conn->conn->event.ctx,
 263                                            dns_conn->tstream,
 264                                            dns_conn->send_queue,
 265                                            call->out_iov, 2);
 266         if (subreq == NULL) {
 267                 dns_tcp_terminate_connection(dns_conn, "dns_tcp_call_loop: "
 268                                 "no memory for tstream_writev_queue_send");
 269                 return;
 270         }
 271         tevent_req_set_callback(subreq, dns_tcp_call_writev_done, call);
 272
 273         /*
 274          * The krb5 tcp pdu's has the length as 4 byte (initial_read_size),
 275          * packet_full_request_u32 provides the pdu length then.
 276          */
 277         subreq = tstream_read_pdu_blob_send(dns_conn,
 278                                             dns_conn->conn->event.ctx,
 279                                             dns_conn->tstream,
 280                                             4, /* initial_read_size */
 281                                             packet_full_request_u32,
 282                                             dns_conn);
 283         if (subreq == NULL) {
 284                 dns_tcp_terminate_connection(dns_conn, "dns_tcp_call_loop: "
 285                                 "no memory for tstream_read_pdu_blob_send");
 286                 return;
 287         }
 288         tevent_req_set_callback(subreq, dns_tcp_call_loop, dns_conn);
 289 }
 290
 291 static void dns_tcp_call_writev_done(struct tevent_req *subreq)
 292 {
 293         struct dns_tcp_call *call = tevent_req_callback_data(subreq,
 294                         struct dns_tcp_call);
 295         int sys_errno;
 296         int rc;
 297
 298         rc = tstream_writev_queue_recv(subreq, &sys_errno);
 299         TALLOC_FREE(subreq);
 300         if (rc == -1) {
 301                 const char *reason;
 302
 303                 reason = talloc_asprintf(call, "dns_tcp_call_writev_done: "
 304                                          "tstream_writev_queue_recv() - %d:%s",
 305                                          sys_errno, strerror(sys_errno));
 306                 if (!reason) {
 307                         reason = "dns_tcp_call_writev_done: tstream_writev_queue_recv() failed";
 308                 }
 309
 310                 dns_tcp_terminate_connection(call->dns_conn, reason);
 311                 return;
 312         }
 313
 314         /* We don't care about errors */
 315
 316         talloc_free(call);
 317 }
 318
 319 /*
 320   called when we get a new connection
 321 */
 322 static void dns_tcp_accept(struct stream_connection *conn)
 323 {
 324         struct dns_socket *dns_socket;
 325         struct dns_tcp_connection *dns_conn;
 326         struct tevent_req *subreq;
 327         int rc;
 328
 329         dns_conn = talloc_zero(conn, struct dns_tcp_connection);
 330         if (dns_conn == NULL) {
 331                 stream_terminate_connection(conn,
 332                                 "dns_tcp_accept: out of memory");
 333                 return;
 334         }
 335
 336         dns_conn->send_queue = tevent_queue_create(conn, "dns_tcp_accept");
 337         if (dns_conn->send_queue == NULL) {
 338                 stream_terminate_connection(conn,
 339                                 "dns_tcp_accept: out of memory");
 340                 return;
 341         }
 342
 343         dns_socket = talloc_get_type(conn->private_data, struct dns_socket);
 344
 345         TALLOC_FREE(conn->event.fde);
 346
 347         rc = tstream_bsd_existing_socket(dns_conn,
 348                         socket_get_fd(conn->socket),
 349                         &dns_conn->tstream);
 350         if (rc < 0) {
 351                 stream_terminate_connection(conn,
 352                                 "dns_tcp_accept: out of memory");
 353                 return;
 354         }
 355
 356         dns_conn->conn = conn;
 357         dns_conn->dns_socket = dns_socket;
 358         conn->private_data = dns_conn;
 359
 360         /*
 361          * The krb5 tcp pdu's has the length as 4 byte (initial_read_size),
 362          * packet_full_request_u32 provides the pdu length then.
 363          */
 364         subreq = tstream_read_pdu_blob_send(dns_conn,
 365                                             dns_conn->conn->event.ctx,
 366                                             dns_conn->tstream,
 367                                             4, /* initial_read_size */
 368                                             packet_full_request_u32,
 369                                             dns_conn);
 370         if (subreq == NULL) {
 371                 dns_tcp_terminate_connection(dns_conn, "dns_tcp_accept: "
 372                                 "no memory for tstream_read_pdu_blob_send");
 373                 return;
 374         }
 375         tevent_req_set_callback(subreq, dns_tcp_call_loop, dns_conn);
 376 }
 377
 378 static const struct stream_server_ops dns_tcp_stream_ops = {
 379         .name                   = "dns_tcp",
 380         .accept_connection      = dns_tcp_accept,
 381         .recv_handler           = dns_tcp_recv,
 382         .send_handler           = dns_tcp_send
 383 };
 384
 385 struct dns_udp_call {
 386         struct tsocket_address *src;
 387         DATA_BLOB in;
 388         DATA_BLOB out;
 389 };
 390
 391 static void dns_udp_call_sendto_done(struct tevent_req *subreq);
 392
 393 static void dns_udp_call_loop(struct tevent_req *subreq)
 394 {
 395         struct dns_udp_socket *sock = tevent_req_callback_data(subreq,
 396                                       struct dns_udp_socket);
 397         struct dns_udp_call *call;
 398         uint8_t *buf;
 399         ssize_t len;
 400         int sys_errno;
 401         NTSTATUS status;
 402
 403         call = talloc(sock, struct dns_udp_call);
 404         if (call == NULL) {
 405                 talloc_free(call);
 406                 goto done;
 407         }
 408
 409         len = tdgram_recvfrom_recv(subreq, &sys_errno,
 410                                    call, &buf, &call->src);
 411         TALLOC_FREE(subreq);
 412         if (len == -1) {
 413                 talloc_free(call);
 414                 goto done;
 415         }
 416
 417         call->in.data = buf;
 418         call->in.length = len;
 419
 420         DEBUG(10,("Received DNS UDP packet of length %lu from %s\n",
 421                  (long)call->in.length,
 422                  tsocket_address_string(call->src, call)));
 423
 424         /* Call dns_process */
 425         status = dns_process(sock->dns_socket->dns, call, &call->in, &call->out);
 426         if (!NT_STATUS_IS_OK(status)) {
 427                 talloc_free(call);
 428                 DEBUG(0, ("dns_process returned %s\n", nt_errstr(status)));
 429                 goto done;
 430         }
 431
 432         subreq = tdgram_sendto_queue_send(call,
 433                                           sock->dns_socket->dns->task->event_ctx,
 434                                           sock->dgram,
 435                                           sock->send_queue,
 436                                           call->out.data,
 437                                           call->out.length,
 438                                           call->src);
 439         if (subreq == NULL) {
 440                 talloc_free(call);
 441                 goto done;
 442         }
 443         tevent_req_set_callback(subreq, dns_udp_call_sendto_done, call);
 444
 445 done:
 446         subreq = tdgram_recvfrom_send(sock,
 447                                       sock->dns_socket->dns->task->event_ctx,
 448                                       sock->dgram);
 449         if (subreq == NULL) {
 450                 task_server_terminate(sock->dns_socket->dns->task,
 451                                       "no memory for tdgram_recvfrom_send",
 452                                       true);
 453                 return;
 454         }
 455         tevent_req_set_callback(subreq, dns_udp_call_loop, sock);
 456 }
 457
 458 static void dns_udp_call_sendto_done(struct tevent_req *subreq)
 459 {
 460         struct dns_udp_call *call = tevent_req_callback_data(subreq,
 461                                        struct dns_udp_call);
 462         ssize_t ret;
 463         int sys_errno;
 464
 465         ret = tdgram_sendto_queue_recv(subreq, &sys_errno);
 466
 467         /* We don't care about errors */
 468
 469         talloc_free(call);
 470 }
 471
 472 /*
 473   start listening on the given address
 474 */
 475 static NTSTATUS dns_add_socket(struct dns_server *dns,
 476                                const struct model_ops *model_ops,
 477                                const char *name,
 478                                const char *address,
 479                                uint16_t port)
 480 {
 481         struct dns_socket *dns_socket;
 482         struct dns_udp_socket *dns_udp_socket;
 483         struct tevent_req *udpsubreq;
 484         NTSTATUS status;
 485         int ret;
 486
 487         dns_socket = talloc(dns, struct dns_socket);
 488         NT_STATUS_HAVE_NO_MEMORY(dns_socket);
 489
 490         dns_socket->dns = dns;
 491
 492         ret = tsocket_address_inet_from_strings(dns_socket, "ip",
 493                                                 address, port,
 494                                                 &dns_socket->local_address);
 495         if (ret != 0) {
 496                 status = map_nt_error_from_unix_common(errno);
 497                 return status;
 498         }
 499
 500         status = stream_setup_socket(dns->task,
 501                                      dns->task->event_ctx,
 502                                      dns->task->lp_ctx,
 503                                      model_ops,
 504                                      &dns_tcp_stream_ops,
 505                                      "ip", address, &port,
 506                                      lpcfg_socket_options(dns->task->lp_ctx),
 507                                      dns_socket);
 508         if (!NT_STATUS_IS_OK(status)) {
 509                 DEBUG(0,("Failed to bind to %s:%u TCP - %s\n",
 510                          address, port, nt_errstr(status)));
 511                 talloc_free(dns_socket);
 512                 return status;
 513         }
 514
 515         dns_udp_socket = talloc(dns_socket, struct dns_udp_socket);
 516         NT_STATUS_HAVE_NO_MEMORY(dns_udp_socket);
 517
 518         dns_udp_socket->dns_socket = dns_socket;
 519
 520         ret = tdgram_inet_udp_socket(dns_socket->local_address,
 521                                      NULL,
 522                                      dns_udp_socket,
 523                                      &dns_udp_socket->dgram);
 524         if (ret != 0) {
 525                 status = map_nt_error_from_unix_common(errno);
 526                 DEBUG(0,("Failed to bind to %s:%u UDP - %s\n",
 527                          address, port, nt_errstr(status)));
 528                 return status;
 529         }
 530
 531         dns_udp_socket->send_queue = tevent_queue_create(dns_udp_socket,
 532                                                          "dns_udp_send_queue");
 533         NT_STATUS_HAVE_NO_MEMORY(dns_udp_socket->send_queue);
 534
 535         udpsubreq = tdgram_recvfrom_send(dns_udp_socket,
 536                                          dns->task->event_ctx,
 537                                          dns_udp_socket->dgram);
 538         NT_STATUS_HAVE_NO_MEMORY(udpsubreq);
 539         tevent_req_set_callback(udpsubreq, dns_udp_call_loop, dns_udp_socket);
 540
 541         return NT_STATUS_OK;
 542 }
 543
 544 /*
 545   setup our listening sockets on the configured network interfaces
 546 */
 547 static NTSTATUS dns_startup_interfaces(struct dns_server *dns, struct loadparm_context *lp_ctx,
 548                                        struct interface *ifaces)
 549 {
 550         const struct model_ops *model_ops;
 551         int num_interfaces;
 552         TALLOC_CTX *tmp_ctx = talloc_new(dns);
 553         NTSTATUS status;
 554         int i;
 555
 556         /* within the dns task we want to be a single process, so
 557            ask for the single process model ops and pass these to the
 558            stream_setup_socket() call. */
 559         model_ops = process_model_startup("single");
 560         if (!model_ops) {
 561                 DEBUG(0,("Can't find 'single' process model_ops\n"));
 562                 return NT_STATUS_INTERNAL_ERROR;
 563         }
 564
 565         num_interfaces = iface_list_count(ifaces);
 566
 567         for (i=0; i<num_interfaces; i++) {
 568                 const char *address = talloc_strdup(tmp_ctx, iface_list_n_ip(ifaces, i));
 569
 570                 status = dns_add_socket(dns, model_ops, "dns", address, DNS_SERVICE_PORT);
 571                 NT_STATUS_NOT_OK_RETURN(status);
 572         }
 573
 574         talloc_free(tmp_ctx);
 575
 576         return NT_STATUS_OK;
 577 }
 578
 579 static int dns_server_sort_zones(struct ldb_message **m1, struct ldb_message **m2)
 580 {
 581         const char *n1, *n2;
 582         size_t l1, l2;
 583
 584         n1 = ldb_msg_find_attr_as_string(*m1, "name", NULL);
 585         n2 = ldb_msg_find_attr_as_string(*m2, "name", NULL);
 586
 587         l1 = strlen(n1);
 588         l2 = strlen(n2);
 589
 590         /* If the string lengths are not equal just sort by length */
 591         if (l1 != l2) {
 592                 /* If m1 is the larger zone name, return it first */
 593                 return l2 - l1;
 594         }
 595
 596         /*TODO: We need to compare DNs here, we want the DomainDNSZones first */
 597         return 0;
 598 }
 599
 600 static void dns_task_init(struct task_server *task)
 601 {
 602         struct dns_server *dns;
 603         NTSTATUS status;
 604         struct interface *ifaces;
 605         int ret;
 606         struct ldb_result *res;
 607         static const char * const attrs[] = { "name", NULL};
 608         unsigned int i;
 609
 610         switch (lpcfg_server_role(task->lp_ctx)) {
 611         case ROLE_STANDALONE:
 612                 task_server_terminate(task, "dns: no DNS required in standalone configuration", false);
 613                 return;
 614         case ROLE_DOMAIN_MEMBER:
 615                 task_server_terminate(task, "dns: no DNS required in member server configuration", false);
 616                 return;
 617         case ROLE_DOMAIN_CONTROLLER:
 618                 /* Yes, we want a DNS */
 619                 break;
 620         }
 621
 622         load_interface_list(task, task->lp_ctx, &ifaces);
 623
 624         if (iface_list_count(ifaces) == 0) {
 625                 task_server_terminate(task, "dns: no network interfaces configured", false);
 626                 return;
 627         }
 628
 629         task_server_set_title(task, "task[dns]");
 630
 631         dns = talloc_zero(task, struct dns_server);
 632         if (dns == NULL) {
 633                 task_server_terminate(task, "dns: out of memory", true);
 634                 return;
 635         }
 636
 637         dns->task = task;
 638
 639         dns->samdb = samdb_connect(dns, dns->task->event_ctx, dns->task->lp_ctx,
 640                               system_session(dns->task->lp_ctx), 0);
 641         if (!dns->samdb) {
 642                 task_server_terminate(task, "dns: samdb_connect failed", true);
 643                 return;
 644         }
 645
 646         // TODO: this search does not work against windows
 647         ret = dsdb_search(dns->samdb, dns, &res, NULL, LDB_SCOPE_SUBTREE,
 648                           attrs, DSDB_SEARCH_SEARCH_ALL_PARTITIONS, "(objectClass=dnsZone)");
 649         if (ret != LDB_SUCCESS) {
 650                 task_server_terminate(task,
 651                                       "dns: failed to look up root DNS zones",
 652                                       true);
 653                 return;
 654         }
 655
 656         TYPESAFE_QSORT(res->msgs, res->count, dns_server_sort_zones);
 657
 658         for (i=0; i < res->count; i++) {
 659                 struct dns_server_zone *z;
 660
 661                 z = talloc_zero(dns, struct dns_server_zone);
 662                 if (z == NULL) {
 663                 }
 664
 665                 z->name = ldb_msg_find_attr_as_string(res->msgs[i], "name", NULL);
 666                 z->dn = talloc_move(z, &res->msgs[i]->dn);
 667
 668                 DLIST_ADD_END(dns->zones, z, NULL);
 669         }
 670
 671         status = dns_startup_interfaces(dns, task->lp_ctx, ifaces);
 672         if (!NT_STATUS_IS_OK(status)) {
 673                 task_server_terminate(task, "dns failed to setup interfaces", true);
 674                 return;
 675         }
 676 }
 677
 678 NTSTATUS server_service_dns_init(void)
 679 {
 680         return register_server_service("dns", dns_task_init);
 681 }