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_request_state *state;
 104         struct dns_name_packet *in_packet;
 105         struct dns_name_packet *out_packet;
 106         struct dns_res_rec *answers = NULL, *nsrecs = NULL, *additional = NULL;
 107         uint16_t num_answers = 0 , num_nsrecs = 0, num_additional = 0;
 108
 109         if (in->length < 12) {
 110                 return NT_STATUS_INVALID_PARAMETER;
 111         }
 112
 113         state = talloc_zero(mem_ctx, struct dns_request_state);
 114
 115         in_packet = talloc_zero(state, struct dns_name_packet);
 116         /* TODO: We don't really need an out_packet. */
 117         out_packet = talloc_zero(state, struct dns_name_packet);
 118
 119         if (in_packet == NULL) return NT_STATUS_NO_MEMORY;
 120         if (out_packet == NULL) return NT_STATUS_NO_MEMORY;
 121
 122         dump_data(2, in->data, in->length);
 123
 124         ndr_err = ndr_pull_struct_blob(in, in_packet, in_packet,
 125                         (ndr_pull_flags_fn_t)ndr_pull_dns_name_packet);
 126         if (!NDR_ERR_CODE_IS_SUCCESS(ndr_err)) {
 127                 TALLOC_FREE(in_packet);
 128                 DEBUG(0, ("Failed to parse packet %d!\n", ndr_err));
 129                 *out = *in;
 130
 131                 out->data[2] |= 0x80; /* Toggle DNS_FLAG_REPLY */
 132                 out->data[3] |= DNS_RCODE_FORMERR;
 133
 134                 return NT_STATUS_OK;
 135         }
 136         if (DEBUGLVL(2)) {
 137                 NDR_PRINT_DEBUG(dns_name_packet, in_packet);
 138         }
 139         *out_packet = *in_packet;
 140         state->flags |= in_packet->operation | DNS_FLAG_REPLY;
 141
 142         /* TODO: Allow setting the forwarding in smb.conf or the like */
 143         state->flags |= DNS_FLAG_RECURSION_AVAIL;
 144
 145         switch (in_packet->operation & DNS_OPCODE) {
 146         case DNS_OPCODE_QUERY:
 147
 148                 ret = dns_server_process_query(dns, state,
 149                                                out_packet, in_packet,
 150                                                &answers, &num_answers,
 151                                                &nsrecs,  &num_nsrecs,
 152                                                &additional, &num_additional);
 153
 154                 break;
 155         case DNS_OPCODE_UPDATE:
 156                 ret = dns_server_process_update(dns, state,
 157                                                 out_packet, in_packet,
 158                                                 &answers, &num_answers,
 159                                                 &nsrecs,  &num_nsrecs,
 160                                                 &additional, &num_additional);
 161                 break;
 162         default:
 163                 ret = WERR_DNS_ERROR_RCODE_NOT_IMPLEMENTED;
 164                 break;
 165         }
 166
 167         if (W_ERROR_IS_OK(ret)) {
 168                 out_packet->ancount = num_answers;
 169                 out_packet->answers = answers;
 170
 171                 out_packet->nscount = num_nsrecs;
 172                 out_packet->nsrecs  = nsrecs;
 173
 174                 out_packet->arcount = num_additional;
 175                 out_packet->additional = additional;
 176         } else {
 177                 out_packet->operation |= werr_to_dns_err(ret);
 178         }
 179
 180         out_packet->operation |= state->flags;
 181
 182         if (DEBUGLVL(2)) {
 183                 NDR_PRINT_DEBUG(dns_name_packet, out_packet);
 184         }
 185         ndr_err = ndr_push_struct_blob(out, out_packet, out_packet,
 186                         (ndr_push_flags_fn_t)ndr_push_dns_name_packet);
 187         if (!NDR_ERR_CODE_IS_SUCCESS(ndr_err)) {
 188                 TALLOC_FREE(in_packet);
 189                 TALLOC_FREE(out_packet);
 190                 DEBUG(0, ("Failed to push packet %d!\n", ndr_err));
 191                 *out = *in;
 192
 193                 out->data[2] |= 0x80; /* Toggle DNS_FLAG_REPLY */
 194                 out->data[3] |= DNS_RCODE_SERVFAIL;
 195
 196                 return NT_STATUS_OK;
 197         }
 198
 199         dump_data(2, out->data, out->length);
 200         return NT_STATUS_OK;
 201 }
 202
 203 struct dns_tcp_call {
 204         struct dns_tcp_connection *dns_conn;
 205         DATA_BLOB in;
 206         DATA_BLOB out;
 207         uint8_t out_hdr[4];
 208         struct iovec out_iov[2];
 209 };
 210
 211 static void dns_tcp_call_writev_done(struct tevent_req *subreq);
 212
 213 static void dns_tcp_call_loop(struct tevent_req *subreq)
 214 {
 215         struct dns_tcp_connection *dns_conn = tevent_req_callback_data(subreq,
 216                                       struct dns_tcp_connection);
 217         struct dns_tcp_call *call;
 218         NTSTATUS status;
 219
 220         call = talloc(dns_conn, struct dns_tcp_call);
 221         if (call == NULL) {
 222                 dns_tcp_terminate_connection(dns_conn, "dns_tcp_call_loop: "
 223                                 "no memory for dns_tcp_call");
 224                 return;
 225         }
 226         call->dns_conn = dns_conn;
 227
 228         status = tstream_read_pdu_blob_recv(subreq,
 229                                             call,
 230                                             &call->in);
 231         TALLOC_FREE(subreq);
 232         if (!NT_STATUS_IS_OK(status)) {
 233                 const char *reason;
 234
 235                 reason = talloc_asprintf(call, "dns_tcp_call_loop: "
 236                                          "tstream_read_pdu_blob_recv() - %s",
 237                                          nt_errstr(status));
 238                 if (!reason) {
 239                         reason = nt_errstr(status);
 240                 }
 241
 242                 dns_tcp_terminate_connection(dns_conn, reason);
 243                 return;
 244         }
 245
 246         DEBUG(10,("Received DNS TCP packet of length %lu from %s\n",
 247                  (long) call->in.length,
 248                  tsocket_address_string(dns_conn->conn->remote_address, call)));
 249
 250         /* skip length header */
 251         call->in.data += 2;
 252         call->in.length -= 2;
 253
 254         /* Call dns */
 255         status = dns_process(dns_conn->dns_socket->dns, call, &call->in, &call->out);
 256         if (!NT_STATUS_IS_OK(status)) {
 257                 DEBUG(0, ("dns_process returned %s\n", nt_errstr(status)));
 258                 dns_tcp_terminate_connection(dns_conn,
 259                                 "dns_tcp_call_loop: process function failed");
 260                 return;
 261         }
 262
 263         /* First add the length of the out buffer */
 264         RSSVAL(call->out_hdr, 0, call->out.length);
 265         call->out_iov[0].iov_base = (char *) call->out_hdr;
 266         call->out_iov[0].iov_len = 2;
 267
 268         call->out_iov[1].iov_base = (char *) call->out.data;
 269         call->out_iov[1].iov_len = call->out.length;
 270
 271         subreq = tstream_writev_queue_send(call,
 272                                            dns_conn->conn->event.ctx,
 273                                            dns_conn->tstream,
 274                                            dns_conn->send_queue,
 275                                            call->out_iov, 2);
 276         if (subreq == NULL) {
 277                 dns_tcp_terminate_connection(dns_conn, "dns_tcp_call_loop: "
 278                                 "no memory for tstream_writev_queue_send");
 279                 return;
 280         }
 281         tevent_req_set_callback(subreq, dns_tcp_call_writev_done, call);
 282
 283         /*
 284          * The dns tcp pdu's has the length as 2 byte (initial_read_size),
 285          * packet_full_request_u16 provides the pdu length then.
 286          */
 287         subreq = tstream_read_pdu_blob_send(dns_conn,
 288                                             dns_conn->conn->event.ctx,
 289                                             dns_conn->tstream,
 290                                             2, /* initial_read_size */
 291                                             packet_full_request_u16,
 292                                             dns_conn);
 293         if (subreq == NULL) {
 294                 dns_tcp_terminate_connection(dns_conn, "dns_tcp_call_loop: "
 295                                 "no memory for tstream_read_pdu_blob_send");
 296                 return;
 297         }
 298         tevent_req_set_callback(subreq, dns_tcp_call_loop, dns_conn);
 299 }
 300
 301 static void dns_tcp_call_writev_done(struct tevent_req *subreq)
 302 {
 303         struct dns_tcp_call *call = tevent_req_callback_data(subreq,
 304                         struct dns_tcp_call);
 305         int sys_errno;
 306         int rc;
 307
 308         rc = tstream_writev_queue_recv(subreq, &sys_errno);
 309         TALLOC_FREE(subreq);
 310         if (rc == -1) {
 311                 const char *reason;
 312
 313                 reason = talloc_asprintf(call, "dns_tcp_call_writev_done: "
 314                                          "tstream_writev_queue_recv() - %d:%s",
 315                                          sys_errno, strerror(sys_errno));
 316                 if (!reason) {
 317                         reason = "dns_tcp_call_writev_done: tstream_writev_queue_recv() failed";
 318                 }
 319
 320                 dns_tcp_terminate_connection(call->dns_conn, reason);
 321                 return;
 322         }
 323
 324         /* We don't care about errors */
 325
 326         talloc_free(call);
 327 }
 328
 329 /*
 330   called when we get a new connection
 331 */
 332 static void dns_tcp_accept(struct stream_connection *conn)
 333 {
 334         struct dns_socket *dns_socket;
 335         struct dns_tcp_connection *dns_conn;
 336         struct tevent_req *subreq;
 337         int rc;
 338
 339         dns_conn = talloc_zero(conn, struct dns_tcp_connection);
 340         if (dns_conn == NULL) {
 341                 stream_terminate_connection(conn,
 342                                 "dns_tcp_accept: out of memory");
 343                 return;
 344         }
 345
 346         dns_conn->send_queue = tevent_queue_create(conn, "dns_tcp_accept");
 347         if (dns_conn->send_queue == NULL) {
 348                 stream_terminate_connection(conn,
 349                                 "dns_tcp_accept: out of memory");
 350                 return;
 351         }
 352
 353         dns_socket = talloc_get_type(conn->private_data, struct dns_socket);
 354
 355         TALLOC_FREE(conn->event.fde);
 356
 357         rc = tstream_bsd_existing_socket(dns_conn,
 358                         socket_get_fd(conn->socket),
 359                         &dns_conn->tstream);
 360         if (rc < 0) {
 361                 stream_terminate_connection(conn,
 362                                 "dns_tcp_accept: out of memory");
 363                 return;
 364         }
 365
 366         dns_conn->conn = conn;
 367         dns_conn->dns_socket = dns_socket;
 368         conn->private_data = dns_conn;
 369
 370         /*
 371          * The dns tcp pdu's has the length as 2 byte (initial_read_size),
 372          * packet_full_request_u16 provides the pdu length then.
 373          */
 374         subreq = tstream_read_pdu_blob_send(dns_conn,
 375                                             dns_conn->conn->event.ctx,
 376                                             dns_conn->tstream,
 377                                             2, /* initial_read_size */
 378                                             packet_full_request_u16,
 379                                             dns_conn);
 380         if (subreq == NULL) {
 381                 dns_tcp_terminate_connection(dns_conn, "dns_tcp_accept: "
 382                                 "no memory for tstream_read_pdu_blob_send");
 383                 return;
 384         }
 385         tevent_req_set_callback(subreq, dns_tcp_call_loop, dns_conn);
 386 }
 387
 388 static const struct stream_server_ops dns_tcp_stream_ops = {
 389         .name                   = "dns_tcp",
 390         .accept_connection      = dns_tcp_accept,
 391         .recv_handler           = dns_tcp_recv,
 392         .send_handler           = dns_tcp_send
 393 };
 394
 395 struct dns_udp_call {
 396         struct tsocket_address *src;
 397         DATA_BLOB in;
 398         DATA_BLOB out;
 399 };
 400
 401 static void dns_udp_call_sendto_done(struct tevent_req *subreq);
 402
 403 static void dns_udp_call_loop(struct tevent_req *subreq)
 404 {
 405         struct dns_udp_socket *sock = tevent_req_callback_data(subreq,
 406                                       struct dns_udp_socket);
 407         struct dns_udp_call *call;
 408         uint8_t *buf;
 409         ssize_t len;
 410         int sys_errno;
 411         NTSTATUS status;
 412
 413         call = talloc(sock, struct dns_udp_call);
 414         if (call == NULL) {
 415                 talloc_free(call);
 416                 goto done;
 417         }
 418
 419         len = tdgram_recvfrom_recv(subreq, &sys_errno,
 420                                    call, &buf, &call->src);
 421         TALLOC_FREE(subreq);
 422         if (len == -1) {
 423                 talloc_free(call);
 424                 goto done;
 425         }
 426
 427         call->in.data = buf;
 428         call->in.length = len;
 429
 430         DEBUG(10,("Received DNS UDP packet of length %lu from %s\n",
 431                  (long)call->in.length,
 432                  tsocket_address_string(call->src, call)));
 433
 434         /* Call dns_process */
 435         status = dns_process(sock->dns_socket->dns, call, &call->in, &call->out);
 436         if (!NT_STATUS_IS_OK(status)) {
 437                 talloc_free(call);
 438                 DEBUG(0, ("dns_process returned %s\n", nt_errstr(status)));
 439                 goto done;
 440         }
 441
 442         subreq = tdgram_sendto_queue_send(call,
 443                                           sock->dns_socket->dns->task->event_ctx,
 444                                           sock->dgram,
 445                                           sock->send_queue,
 446                                           call->out.data,
 447                                           call->out.length,
 448                                           call->src);
 449         if (subreq == NULL) {
 450                 talloc_free(call);
 451                 goto done;
 452         }
 453         tevent_req_set_callback(subreq, dns_udp_call_sendto_done, call);
 454
 455 done:
 456         subreq = tdgram_recvfrom_send(sock,
 457                                       sock->dns_socket->dns->task->event_ctx,
 458                                       sock->dgram);
 459         if (subreq == NULL) {
 460                 task_server_terminate(sock->dns_socket->dns->task,
 461                                       "no memory for tdgram_recvfrom_send",
 462                                       true);
 463                 return;
 464         }
 465         tevent_req_set_callback(subreq, dns_udp_call_loop, sock);
 466 }
 467
 468 static void dns_udp_call_sendto_done(struct tevent_req *subreq)
 469 {
 470         struct dns_udp_call *call = tevent_req_callback_data(subreq,
 471                                        struct dns_udp_call);
 472         ssize_t ret;
 473         int sys_errno;
 474
 475         ret = tdgram_sendto_queue_recv(subreq, &sys_errno);
 476
 477         /* We don't care about errors */
 478
 479         talloc_free(call);
 480 }
 481
 482 /*
 483   start listening on the given address
 484 */
 485 static NTSTATUS dns_add_socket(struct dns_server *dns,
 486                                const struct model_ops *model_ops,
 487                                const char *name,
 488                                const char *address,
 489                                uint16_t port)
 490 {
 491         struct dns_socket *dns_socket;
 492         struct dns_udp_socket *dns_udp_socket;
 493         struct tevent_req *udpsubreq;
 494         NTSTATUS status;
 495         int ret;
 496
 497         dns_socket = talloc(dns, struct dns_socket);
 498         NT_STATUS_HAVE_NO_MEMORY(dns_socket);
 499
 500         dns_socket->dns = dns;
 501
 502         ret = tsocket_address_inet_from_strings(dns_socket, "ip",
 503                                                 address, port,
 504                                                 &dns_socket->local_address);
 505         if (ret != 0) {
 506                 status = map_nt_error_from_unix_common(errno);
 507                 return status;
 508         }
 509
 510         status = stream_setup_socket(dns->task,
 511                                      dns->task->event_ctx,
 512                                      dns->task->lp_ctx,
 513                                      model_ops,
 514                                      &dns_tcp_stream_ops,
 515                                      "ip", address, &port,
 516                                      lpcfg_socket_options(dns->task->lp_ctx),
 517                                      dns_socket);
 518         if (!NT_STATUS_IS_OK(status)) {
 519                 DEBUG(0,("Failed to bind to %s:%u TCP - %s\n",
 520                          address, port, nt_errstr(status)));
 521                 talloc_free(dns_socket);
 522                 return status;
 523         }
 524
 525         dns_udp_socket = talloc(dns_socket, struct dns_udp_socket);
 526         NT_STATUS_HAVE_NO_MEMORY(dns_udp_socket);
 527
 528         dns_udp_socket->dns_socket = dns_socket;
 529
 530         ret = tdgram_inet_udp_socket(dns_socket->local_address,
 531                                      NULL,
 532                                      dns_udp_socket,
 533                                      &dns_udp_socket->dgram);
 534         if (ret != 0) {
 535                 status = map_nt_error_from_unix_common(errno);
 536                 DEBUG(0,("Failed to bind to %s:%u UDP - %s\n",
 537                          address, port, nt_errstr(status)));
 538                 return status;
 539         }
 540
 541         dns_udp_socket->send_queue = tevent_queue_create(dns_udp_socket,
 542                                                          "dns_udp_send_queue");
 543         NT_STATUS_HAVE_NO_MEMORY(dns_udp_socket->send_queue);
 544
 545         udpsubreq = tdgram_recvfrom_send(dns_udp_socket,
 546                                          dns->task->event_ctx,
 547                                          dns_udp_socket->dgram);
 548         NT_STATUS_HAVE_NO_MEMORY(udpsubreq);
 549         tevent_req_set_callback(udpsubreq, dns_udp_call_loop, dns_udp_socket);
 550
 551         return NT_STATUS_OK;
 552 }
 553
 554 /*
 555   setup our listening sockets on the configured network interfaces
 556 */
 557 static NTSTATUS dns_startup_interfaces(struct dns_server *dns, struct loadparm_context *lp_ctx,
 558                                        struct interface *ifaces)
 559 {
 560         const struct model_ops *model_ops;
 561         int num_interfaces;
 562         TALLOC_CTX *tmp_ctx = talloc_new(dns);
 563         NTSTATUS status;
 564         int i;
 565
 566         /* within the dns task we want to be a single process, so
 567            ask for the single process model ops and pass these to the
 568            stream_setup_socket() call. */
 569         model_ops = process_model_startup("single");
 570         if (!model_ops) {
 571                 DEBUG(0,("Can't find 'single' process model_ops\n"));
 572                 return NT_STATUS_INTERNAL_ERROR;
 573         }
 574
 575         num_interfaces = iface_list_count(ifaces);
 576
 577         for (i=0; i<num_interfaces; i++) {
 578                 const char *address = talloc_strdup(tmp_ctx, iface_list_n_ip(ifaces, i));
 579
 580                 status = dns_add_socket(dns, model_ops, "dns", address, DNS_SERVICE_PORT);
 581                 NT_STATUS_NOT_OK_RETURN(status);
 582         }
 583
 584         talloc_free(tmp_ctx);
 585
 586         return NT_STATUS_OK;
 587 }
 588
 589 static int dns_server_sort_zones(struct ldb_message **m1, struct ldb_message **m2)
 590 {
 591         const char *n1, *n2;
 592         size_t l1, l2;
 593
 594         n1 = ldb_msg_find_attr_as_string(*m1, "name", NULL);
 595         n2 = ldb_msg_find_attr_as_string(*m2, "name", NULL);
 596
 597         l1 = strlen(n1);
 598         l2 = strlen(n2);
 599
 600         /* If the string lengths are not equal just sort by length */
 601         if (l1 != l2) {
 602                 /* If m1 is the larger zone name, return it first */
 603                 return l2 - l1;
 604         }
 605
 606         /*TODO: We need to compare DNs here, we want the DomainDNSZones first */
 607         return 0;
 608 }
 609
 610 static void dns_task_init(struct task_server *task)
 611 {
 612         struct dns_server *dns;
 613         NTSTATUS status;
 614         struct interface *ifaces;
 615         int ret;
 616         struct ldb_result *res;
 617         static const char * const attrs[] = { "name", NULL};
 618         unsigned int i;
 619
 620         switch (lpcfg_server_role(task->lp_ctx)) {
 621         case ROLE_STANDALONE:
 622                 task_server_terminate(task, "dns: no DNS required in standalone configuration", false);
 623                 return;
 624         case ROLE_DOMAIN_MEMBER:
 625                 task_server_terminate(task, "dns: no DNS required in member server configuration", false);
 626                 return;
 627         case ROLE_DOMAIN_CONTROLLER:
 628                 /* Yes, we want a DNS */
 629                 break;
 630         }
 631
 632         load_interface_list(task, task->lp_ctx, &ifaces);
 633
 634         if (iface_list_count(ifaces) == 0) {
 635                 task_server_terminate(task, "dns: no network interfaces configured", false);
 636                 return;
 637         }
 638
 639         task_server_set_title(task, "task[dns]");
 640
 641         dns = talloc_zero(task, struct dns_server);
 642         if (dns == NULL) {
 643                 task_server_terminate(task, "dns: out of memory", true);
 644                 return;
 645         }
 646
 647         dns->task = task;
 648
 649         dns->samdb = samdb_connect(dns, dns->task->event_ctx, dns->task->lp_ctx,
 650                               system_session(dns->task->lp_ctx), 0);
 651         if (!dns->samdb) {
 652                 task_server_terminate(task, "dns: samdb_connect failed", true);
 653                 return;
 654         }
 655
 656         // TODO: this search does not work against windows
 657         ret = dsdb_search(dns->samdb, dns, &res, NULL, LDB_SCOPE_SUBTREE,
 658                           attrs, DSDB_SEARCH_SEARCH_ALL_PARTITIONS, "(objectClass=dnsZone)");
 659         if (ret != LDB_SUCCESS) {
 660                 task_server_terminate(task,
 661                                       "dns: failed to look up root DNS zones",
 662                                       true);
 663                 return;
 664         }
 665
 666         TYPESAFE_QSORT(res->msgs, res->count, dns_server_sort_zones);
 667
 668         for (i=0; i < res->count; i++) {
 669                 struct dns_server_zone *z;
 670
 671                 z = talloc_zero(dns, struct dns_server_zone);
 672                 if (z == NULL) {
 673                 }
 674
 675                 z->name = ldb_msg_find_attr_as_string(res->msgs[i], "name", NULL);
 676                 z->dn = talloc_move(z, &res->msgs[i]->dn);
 677
 678                 DLIST_ADD_END(dns->zones, z, NULL);
 679         }
 680
 681         status = dns_startup_interfaces(dns, task->lp_ctx, ifaces);
 682         if (!NT_STATUS_IS_OK(status)) {
 683                 task_server_terminate(task, "dns failed to setup interfaces", true);
 684                 return;
 685         }
 686 }
 687
 688 NTSTATUS server_service_dns_init(void)
 689 {
 690         return register_server_service("dns", dns_task_init);
 691 }