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 /* 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_process(struct dns_server *dns,
  95                             TALLOC_CTX *mem_ctx,
  96                             DATA_BLOB *in,
  97                             DATA_BLOB *out)
  98 {
  99         enum ndr_err_code ndr_err;
 100         WERROR ret;
 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;
 105
 106         if (in->length < 12) {
 107                 return NT_STATUS_INVALID_PARAMETER;
 108         }
 109
 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);
 113
 114         if (in_packet == NULL) return NT_STATUS_NO_MEMORY;
 115         if (out_packet == NULL) return NT_STATUS_NO_MEMORY;
 116
 117         dump_data(2, in->data, in->length);
 118
 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));
 124                 *out = *in;
 125
 126                 out->data[2] |= 0x80; /* Toggle DNS_FLAG_REPLY */
 127                 out->data[3] |= DNS_RCODE_FORMERR;
 128
 129                 return NT_STATUS_OK;
 130         }
 131
 132         NDR_PRINT_DEBUG(dns_name_packet, in_packet);
 133         *out_packet = *in_packet;
 134         out_packet->operation |= DNS_FLAG_REPLY;
 135
 136         switch (in_packet->operation & DNS_OPCODE) {
 137         case DNS_OPCODE_QUERY:
 138
 139                 ret = dns_server_process_query(dns, out_packet, in_packet,
 140                                                &answers, &num_answers,
 141                                                &nsrecs,  &num_nsrecs,
 142                                                &additional, &num_additional);
 143
 144                 break;
 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);
 150                 break;
 151         default:
 152                 ret = WERR_DNS_ERROR_RCODE_NOT_IMPLEMENTED;
 153                 break;
 154         }
 155
 156         if (W_ERROR_IS_OK(ret)) {
 157                 out_packet->ancount = num_answers;
 158                 out_packet->answers = answers;
 159
 160                 out_packet->nscount = num_nsrecs;
 161                 out_packet->nsrecs  = nsrecs;
 162
 163                 out_packet->arcount = num_additional;
 164                 out_packet->additional = additional;
 165         } else {
 166                 out_packet->operation |= werr_to_dns_err(ret);
 167         }
 168
 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));
 176                 *out = *in;
 177
 178                 out->data[2] |= 0x80; /* Toggle DNS_FLAG_REPLY */
 179                 out->data[3] |= DNS_RCODE_SERVFAIL;
 180
 181                 return NT_STATUS_OK;
 182         }
 183
 184         dump_data(2, out->data, out->length);
 185         return NT_STATUS_OK;
 186 }
 187
 188 struct dns_tcp_call {
 189         struct dns_tcp_connection *dns_conn;
 190         DATA_BLOB in;
 191         DATA_BLOB out;
 192         uint8_t out_hdr[4];
 193         struct iovec out_iov[2];
 194 };
 195
 196 static void dns_tcp_call_writev_done(struct tevent_req *subreq);
 197
 198 static void dns_tcp_call_loop(struct tevent_req *subreq)
 199 {
 200         struct dns_tcp_connection *dns_conn = tevent_req_callback_data(subreq,
 201                                       struct dns_tcp_connection);
 202         struct dns_tcp_call *call;
 203         NTSTATUS status;
 204
 205         call = talloc(dns_conn, struct dns_tcp_call);
 206         if (call == NULL) {
 207                 dns_tcp_terminate_connection(dns_conn, "dns_tcp_call_loop: "
 208                                 "no memory for dns_tcp_call");
 209                 return;
 210         }
 211         call->dns_conn = dns_conn;
 212
 213         status = tstream_read_pdu_blob_recv(subreq,
 214                                             call,
 215                                             &call->in);
 216         TALLOC_FREE(subreq);
 217         if (!NT_STATUS_IS_OK(status)) {
 218                 const char *reason;
 219
 220                 reason = talloc_asprintf(call, "dns_tcp_call_loop: "
 221                                          "tstream_read_pdu_blob_recv() - %s",
 222                                          nt_errstr(status));
 223                 if (!reason) {
 224                         reason = nt_errstr(status);
 225                 }
 226
 227                 dns_tcp_terminate_connection(dns_conn, reason);
 228                 return;
 229         }
 230
 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)));
 234
 235         /* skip length header */
 236         call->in.data +=4;
 237         call->in.length -= 4;
 238
 239         /* Call dns */
 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");
 245                 return;
 246         }
 247
 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;
 252
 253         call->out_iov[1].iov_base = (char *) call->out.data;
 254         call->out_iov[1].iov_len = call->out.length;
 255
 256         subreq = tstream_writev_queue_send(call,
 257                                            dns_conn->conn->event.ctx,
 258                                            dns_conn->tstream,
 259                                            dns_conn->send_queue,
 260                                            call->out_iov, 2);
 261         if (subreq == NULL) {
 262                 dns_tcp_terminate_connection(dns_conn, "dns_tcp_call_loop: "
 263                                 "no memory for tstream_writev_queue_send");
 264                 return;
 265         }
 266         tevent_req_set_callback(subreq, dns_tcp_call_writev_done, call);
 267
 268         /*
 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.
 271          */
 272         subreq = tstream_read_pdu_blob_send(dns_conn,
 273                                             dns_conn->conn->event.ctx,
 274                                             dns_conn->tstream,
 275                                             4, /* initial_read_size */
 276                                             packet_full_request_u32,
 277                                             dns_conn);
 278         if (subreq == NULL) {
 279                 dns_tcp_terminate_connection(dns_conn, "dns_tcp_call_loop: "
 280                                 "no memory for tstream_read_pdu_blob_send");
 281                 return;
 282         }
 283         tevent_req_set_callback(subreq, dns_tcp_call_loop, dns_conn);
 284 }
 285
 286 static void dns_tcp_call_writev_done(struct tevent_req *subreq)
 287 {
 288         struct dns_tcp_call *call = tevent_req_callback_data(subreq,
 289                         struct dns_tcp_call);
 290         int sys_errno;
 291         int rc;
 292
 293         rc = tstream_writev_queue_recv(subreq, &sys_errno);
 294         TALLOC_FREE(subreq);
 295         if (rc == -1) {
 296                 const char *reason;
 297
 298                 reason = talloc_asprintf(call, "dns_tcp_call_writev_done: "
 299                                          "tstream_writev_queue_recv() - %d:%s",
 300                                          sys_errno, strerror(sys_errno));
 301                 if (!reason) {
 302                         reason = "dns_tcp_call_writev_done: tstream_writev_queue_recv() failed";
 303                 }
 304
 305                 dns_tcp_terminate_connection(call->dns_conn, reason);
 306                 return;
 307         }
 308
 309         /* We don't care about errors */
 310
 311         talloc_free(call);
 312 }
 313
 314 /*
 315   called when we get a new connection
 316 */
 317 static void dns_tcp_accept(struct stream_connection *conn)
 318 {
 319         struct dns_socket *dns_socket;
 320         struct dns_tcp_connection *dns_conn;
 321         struct tevent_req *subreq;
 322         int rc;
 323
 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");
 328                 return;
 329         }
 330
 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");
 335                 return;
 336         }
 337
 338         dns_socket = talloc_get_type(conn->private_data, struct dns_socket);
 339
 340         TALLOC_FREE(conn->event.fde);
 341
 342         rc = tstream_bsd_existing_socket(dns_conn,
 343                         socket_get_fd(conn->socket),
 344                         &dns_conn->tstream);
 345         if (rc < 0) {
 346                 stream_terminate_connection(conn,
 347                                 "dns_tcp_accept: out of memory");
 348                 return;
 349         }
 350
 351         dns_conn->conn = conn;
 352         dns_conn->dns_socket = dns_socket;
 353         conn->private_data = dns_conn;
 354
 355         /*
 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.
 358          */
 359         subreq = tstream_read_pdu_blob_send(dns_conn,
 360                                             dns_conn->conn->event.ctx,
 361                                             dns_conn->tstream,
 362                                             4, /* initial_read_size */
 363                                             packet_full_request_u32,
 364                                             dns_conn);
 365         if (subreq == NULL) {
 366                 dns_tcp_terminate_connection(dns_conn, "dns_tcp_accept: "
 367                                 "no memory for tstream_read_pdu_blob_send");
 368                 return;
 369         }
 370         tevent_req_set_callback(subreq, dns_tcp_call_loop, dns_conn);
 371 }
 372
 373 static const struct stream_server_ops dns_tcp_stream_ops = {
 374         .name                   = "dns_tcp",
 375         .accept_connection      = dns_tcp_accept,
 376         .recv_handler           = dns_tcp_recv,
 377         .send_handler           = dns_tcp_send
 378 };
 379
 380 struct dns_udp_call {
 381         struct tsocket_address *src;
 382         DATA_BLOB in;
 383         DATA_BLOB out;
 384 };
 385
 386 static void dns_udp_call_sendto_done(struct tevent_req *subreq);
 387
 388 static void dns_udp_call_loop(struct tevent_req *subreq)
 389 {
 390         struct dns_udp_socket *sock = tevent_req_callback_data(subreq,
 391                                       struct dns_udp_socket);
 392         struct dns_udp_call *call;
 393         uint8_t *buf;
 394         ssize_t len;
 395         int sys_errno;
 396         NTSTATUS status;
 397
 398         call = talloc(sock, struct dns_udp_call);
 399         if (call == NULL) {
 400                 talloc_free(call);
 401                 goto done;
 402         }
 403
 404         len = tdgram_recvfrom_recv(subreq, &sys_errno,
 405                                    call, &buf, &call->src);
 406         TALLOC_FREE(subreq);
 407         if (len == -1) {
 408                 talloc_free(call);
 409                 goto done;
 410         }
 411
 412         call->in.data = buf;
 413         call->in.length = len;
 414
 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)));
 418
 419         /* Call krb5 */
 420         status = dns_process(sock->dns_socket->dns, call, &call->in, &call->out);
 421         if (!NT_STATUS_IS_OK(status)) {
 422                 talloc_free(call);
 423                 DEBUG(0, ("dns_process returned %s\n", nt_errstr(status)));
 424                 goto done;
 425         }
 426
 427         subreq = tdgram_sendto_queue_send(call,
 428                                           sock->dns_socket->dns->task->event_ctx,
 429                                           sock->dgram,
 430                                           sock->send_queue,
 431                                           call->out.data,
 432                                           call->out.length,
 433                                           call->src);
 434         if (subreq == NULL) {
 435                 talloc_free(call);
 436                 goto done;
 437         }
 438         tevent_req_set_callback(subreq, dns_udp_call_sendto_done, call);
 439
 440 done:
 441         subreq = tdgram_recvfrom_send(sock,
 442                                       sock->dns_socket->dns->task->event_ctx,
 443                                       sock->dgram);
 444         if (subreq == NULL) {
 445                 task_server_terminate(sock->dns_socket->dns->task,
 446                                       "no memory for tdgram_recvfrom_send",
 447                                       true);
 448                 return;
 449         }
 450         tevent_req_set_callback(subreq, dns_udp_call_loop, sock);
 451 }
 452
 453 static void dns_udp_call_sendto_done(struct tevent_req *subreq)
 454 {
 455         struct dns_udp_call *call = tevent_req_callback_data(subreq,
 456                                        struct dns_udp_call);
 457         ssize_t ret;
 458         int sys_errno;
 459
 460         ret = tdgram_sendto_queue_recv(subreq, &sys_errno);
 461
 462         /* We don't care about errors */
 463
 464         talloc_free(call);
 465 }
 466
 467 /*
 468   start listening on the given address
 469 */
 470 static NTSTATUS dns_add_socket(struct dns_server *dns,
 471                                const struct model_ops *model_ops,
 472                                const char *name,
 473                                const char *address,
 474                                uint16_t port)
 475 {
 476         struct dns_socket *dns_socket;
 477         struct dns_udp_socket *dns_udp_socket;
 478         struct tevent_req *udpsubreq;
 479         NTSTATUS status;
 480         int ret;
 481
 482         dns_socket = talloc(dns, struct dns_socket);
 483         NT_STATUS_HAVE_NO_MEMORY(dns_socket);
 484
 485         dns_socket->dns = dns;
 486
 487         ret = tsocket_address_inet_from_strings(dns_socket, "ip",
 488                                                 address, port,
 489                                                 &dns_socket->local_address);
 490         if (ret != 0) {
 491                 status = map_nt_error_from_unix(errno);
 492                 return status;
 493         }
 494
 495         status = stream_setup_socket(dns->task->event_ctx,
 496                                      dns->task->lp_ctx,
 497                                      model_ops,
 498                                      &dns_tcp_stream_ops,
 499                                      "ip", address, &port,
 500                                      lpcfg_socket_options(dns->task->lp_ctx),
 501                                      dns_socket);
 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);
 506                 return status;
 507         }
 508
 509         dns_udp_socket = talloc(dns_socket, struct dns_udp_socket);
 510         NT_STATUS_HAVE_NO_MEMORY(dns_udp_socket);
 511
 512         dns_udp_socket->dns_socket = dns_socket;
 513
 514         ret = tdgram_inet_udp_socket(dns_socket->local_address,
 515                                      NULL,
 516                                      dns_udp_socket,
 517                                      &dns_udp_socket->dgram);
 518         if (ret != 0) {
 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)));
 522                 return status;
 523         }
 524
 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);
 528
 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);
 534
 535         return NT_STATUS_OK;
 536 }
 537
 538 /*
 539   setup our listening sockets on the configured network interfaces
 540 */
 541 static NTSTATUS dns_startup_interfaces(struct dns_server *dns, struct loadparm_context *lp_ctx,
 542                                        struct interface *ifaces)
 543 {
 544         const struct model_ops *model_ops;
 545         int num_interfaces;
 546         TALLOC_CTX *tmp_ctx = talloc_new(dns);
 547         NTSTATUS status;
 548         int i;
 549
 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("single");
 554         if (!model_ops) {
 555                 DEBUG(0,("Can't find 'single' process model_ops\n"));
 556                 return NT_STATUS_INTERNAL_ERROR;
 557         }
 558
 559         num_interfaces = iface_count(ifaces);
 560
 561         for (i=0; i<num_interfaces; i++) {
 562                 const char *address = talloc_strdup(tmp_ctx, iface_n_ip(ifaces, i));
 563
 564                 status = dns_add_socket(dns, model_ops, "dns", address, DNS_SERVICE_PORT);
 565                 NT_STATUS_NOT_OK_RETURN(status);
 566         }
 567
 568         talloc_free(tmp_ctx);
 569
 570         return NT_STATUS_OK;
 571 }
 572
 573 static int dns_server_sort_zones(struct ldb_message **m1, struct ldb_message **m2)
 574 {
 575         const char *n1, *n2;
 576         size_t l1, l2;
 577
 578         n1 = ldb_msg_find_attr_as_string(*m1, "name", NULL);
 579         n2 = ldb_msg_find_attr_as_string(*m2, "name", NULL);
 580
 581         l1 = strlen(n1);
 582         l2 = strlen(n2);
 583
 584         /* If the string lengths are not equal just sort by length */
 585         if (l1 != l2) {
 586                 /* If m1 is the larger zone name, return it first */
 587                 return l2 - l1;
 588         }
 589
 590         /*TODO: We need to compare DNs here, we want the DomainDNSZones first */
 591         return 0;
 592 }
 593
 594 static void dns_task_init(struct task_server *task)
 595 {
 596         struct dns_server *dns;
 597         NTSTATUS status;
 598         struct interface *ifaces;
 599         int ret;
 600         struct ldb_result *res;
 601         struct ldb_dn *rootdn;
 602         static const char * const attrs[] = { "name", NULL};
 603         unsigned int i;
 604
 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);
 608                 return;
 609         case ROLE_DOMAIN_MEMBER:
 610                 task_server_terminate(task, "dns: no DNS required in member server configuration", false);
 611                 return;
 612         case ROLE_DOMAIN_CONTROLLER:
 613                 /* Yes, we want a DNS */
 614                 break;
 615         }
 616
 617         load_interfaces(task, lpcfg_interfaces(task->lp_ctx), &ifaces);
 618
 619         if (iface_count(ifaces) == 0) {
 620                 task_server_terminate(task, "dns: no network interfaces configured", false);
 621                 return;
 622         }
 623
 624         task_server_set_title(task, "task[dns]");
 625
 626         dns = talloc_zero(task, struct dns_server);
 627         if (dns == NULL) {
 628                 task_server_terminate(task, "dns: out of memory", true);
 629                 return;
 630         }
 631
 632         dns->task = task;
 633
 634         dns->samdb = samdb_connect(dns, dns->task->event_ctx, dns->task->lp_ctx,
 635                               system_session(dns->task->lp_ctx), 0);
 636         if (!dns->samdb) {
 637                 task_server_terminate(task, "dns: samdb_connect failed", true);
 638                 return;
 639         }
 640
 641         rootdn = ldb_dn_new(dns, dns->samdb, "");
 642         if (rootdn == NULL) {
 643                 task_server_terminate(task, "dns: out of memory", true);
 644                 return;
 645         }
 646
 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",
 653                                       true);
 654                 return;
 655         }
 656
 657         TYPESAFE_QSORT(res->msgs, res->count, dns_server_sort_zones);
 658
 659         for (i=0; i < res->count; i++) {
 660                 struct dns_server_zone *z;
 661
 662                 z = talloc_zero(dns, struct dns_server_zone);
 663                 if (z == NULL) {
 664                 }
 665
 666                 z->name = ldb_msg_find_attr_as_string(res->msgs[i], "name", NULL);
 667                 z->dn = talloc_move(z, &res->msgs[i]->dn);
 668
 669                 DLIST_ADD_END(dns->zones, z, NULL);
 670         }
 671
 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);
 675                 return;
 676         }
 677 }
 678
 679 NTSTATUS server_service_dns_init(void)
 680 {
 681         return register_server_service("dns", dns_task_init);
 682 }