source4/dns_server/dns_query.c

   1 /*
   2    Unix SMB/CIFS implementation.
   3
   4    DNS server handler for queries
   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 "libcli/util/werror.h"
  25 #include "librpc/ndr/libndr.h"
  26 #include "librpc/gen_ndr/ndr_dns.h"
  27 #include "librpc/gen_ndr/ndr_dnsp.h"
  28 #include <ldb.h>
  29 #include "param/param.h"
  30 #include "dsdb/samdb/samdb.h"
  31 #include "dsdb/common/util.h"
  32 #include "dns_server/dns_server.h"
  33 #include "libcli/dns/libdns.h"
  34 #include "lib/util/util_net.h"
  35 #include "lib/util/tevent_werror.h"
  36 #include "auth/auth.h"
  37 #include "auth/credentials/credentials.h"
  38 #include "auth/gensec/gensec.h"
  39
  40 static WERROR create_response_rr(const struct dns_name_question *question,
  41                                  const struct dnsp_DnssrvRpcRecord *rec,
  42                                  struct dns_res_rec **answers, uint16_t *ancount)
  43 {
  44         struct dns_res_rec *ans = *answers;
  45         uint16_t ai = *ancount;
  46         char *tmp;
  47         uint32_t i;
  48
  49         ZERO_STRUCT(ans[ai]);
  50
  51         switch (rec->wType) {
  52         case DNS_QTYPE_CNAME:
  53                 ans[ai].rdata.cname_record = talloc_strdup(ans, rec->data.cname);
  54                 W_ERROR_HAVE_NO_MEMORY(ans[ai].rdata.cname_record);
  55                 break;
  56         case DNS_QTYPE_A:
  57                 ans[ai].rdata.ipv4_record = talloc_strdup(ans, rec->data.ipv4);
  58                 W_ERROR_HAVE_NO_MEMORY(ans[ai].rdata.ipv4_record);
  59                 break;
  60         case DNS_QTYPE_AAAA:
  61                 ans[ai].rdata.ipv6_record = talloc_strdup(ans, rec->data.ipv6);
  62                 W_ERROR_HAVE_NO_MEMORY(ans[ai].rdata.ipv6_record);
  63                 break;
  64         case DNS_TYPE_NS:
  65                 ans[ai].rdata.ns_record = talloc_strdup(ans, rec->data.ns);
  66                 W_ERROR_HAVE_NO_MEMORY(ans[ai].rdata.ns_record);
  67                 break;
  68         case DNS_QTYPE_SRV:
  69                 ans[ai].rdata.srv_record.priority = rec->data.srv.wPriority;
  70                 ans[ai].rdata.srv_record.weight   = rec->data.srv.wWeight;
  71                 ans[ai].rdata.srv_record.port     = rec->data.srv.wPort;
  72                 ans[ai].rdata.srv_record.target   = talloc_strdup(
  73                         ans, rec->data.srv.nameTarget);
  74                 W_ERROR_HAVE_NO_MEMORY(ans[ai].rdata.srv_record.target);
  75                 break;
  76         case DNS_QTYPE_SOA:
  77                 ans[ai].rdata.soa_record.mname   = talloc_strdup(
  78                         ans, rec->data.soa.mname);
  79                 W_ERROR_HAVE_NO_MEMORY(ans[ai].rdata.soa_record.mname);
  80                 ans[ai].rdata.soa_record.rname   = talloc_strdup(
  81                         ans, rec->data.soa.rname);
  82                 W_ERROR_HAVE_NO_MEMORY(ans[ai].rdata.soa_record.rname);
  83                 ans[ai].rdata.soa_record.serial  = rec->data.soa.serial;
  84                 ans[ai].rdata.soa_record.refresh = rec->data.soa.refresh;
  85                 ans[ai].rdata.soa_record.retry   = rec->data.soa.retry;
  86                 ans[ai].rdata.soa_record.expire  = rec->data.soa.expire;
  87                 ans[ai].rdata.soa_record.minimum = rec->data.soa.minimum;
  88                 break;
  89         case DNS_QTYPE_PTR:
  90                 ans[ai].rdata.ptr_record = talloc_strdup(ans, rec->data.ptr);
  91                 break;
  92         case DNS_QTYPE_MX:
  93                 ans[ai].rdata.mx_record.preference = rec->data.mx.wPriority;
  94                 ans[ai].rdata.mx_record.exchange = talloc_strdup(
  95                         ans, rec->data.mx.nameTarget);
  96                 if (ans[ai].rdata.mx_record.exchange == NULL) {
  97                         return WERR_NOMEM;
  98                 }
  99                 break;
 100         case DNS_QTYPE_TXT:
 101                 tmp = talloc_asprintf(ans, "\"%s\"", rec->data.txt.str[0]);
 102                 W_ERROR_HAVE_NO_MEMORY(tmp);
 103                 for (i=1; i<rec->data.txt.count; i++) {
 104                         tmp = talloc_asprintf_append_buffer(
 105                                 tmp, " \"%s\"", rec->data.txt.str[i]);
 106                         W_ERROR_HAVE_NO_MEMORY(tmp);
 107                 }
 108                 ans[ai].rdata.txt_record.txt = tmp;
 109                 break;
 110         default:
 111                 DEBUG(0, ("Got unhandled type %u query.\n", rec->wType));
 112                 return DNS_ERR(NOT_IMPLEMENTED);
 113         }
 114
 115         ans[ai].name = talloc_strdup(ans, question->name);
 116         W_ERROR_HAVE_NO_MEMORY(ans[ai].name);
 117         ans[ai].rr_type = rec->wType;
 118         ans[ai].rr_class = DNS_QCLASS_IN;
 119         ans[ai].ttl = rec->dwTtlSeconds;
 120         ans[ai].length = UINT16_MAX;
 121         ai++;
 122
 123         *answers = ans;
 124         *ancount = ai;
 125
 126         return WERR_OK;
 127 }
 128
 129 struct ask_forwarder_state {
 130         struct tevent_context *ev;
 131         uint16_t id;
 132         struct dns_name_packet in_packet;
 133 };
 134
 135 static void ask_forwarder_done(struct tevent_req *subreq);
 136
 137 static struct tevent_req *ask_forwarder_send(
 138         struct dns_server *dns,
 139         TALLOC_CTX *mem_ctx, struct tevent_context *ev,
 140         const char *forwarder, struct dns_name_question *question)
 141 {
 142         struct tevent_req *req, *subreq;
 143         struct ask_forwarder_state *state;
 144         struct dns_res_rec *options;
 145         struct dns_name_packet out_packet = { 0, };
 146         DATA_BLOB out_blob;
 147         enum ndr_err_code ndr_err;
 148         WERROR werr;
 149
 150         req = tevent_req_create(mem_ctx, &state, struct ask_forwarder_state);
 151         if (req == NULL) {
 152                 return NULL;
 153         }
 154         state->ev = ev;
 155         generate_random_buffer((uint8_t *)&state->id, sizeof(state->id));
 156
 157         if (!is_ipaddress(forwarder)) {
 158                 DEBUG(0, ("Invalid 'dns forwarder' setting '%s', needs to be "
 159                           "an IP address\n", forwarder));
 160                 tevent_req_werror(req, DNS_ERR(NAME_ERROR));
 161                 return tevent_req_post(req, ev);
 162         }
 163
 164         out_packet.id = state->id;
 165         out_packet.operation |= DNS_OPCODE_QUERY | DNS_FLAG_RECURSION_DESIRED;
 166         out_packet.qdcount = 1;
 167         out_packet.questions = question;
 168
 169         werr = dns_generate_options(dns, state, &options);
 170         if (!W_ERROR_IS_OK(werr)) {
 171                 tevent_req_werror(req, werr);
 172                 return tevent_req_post(req, ev);
 173         }
 174
 175         out_packet.arcount = 1;
 176         out_packet.additional = options;
 177
 178         ndr_err = ndr_push_struct_blob(
 179                 &out_blob, state, &out_packet,
 180                 (ndr_push_flags_fn_t)ndr_push_dns_name_packet);
 181         if (!NDR_ERR_CODE_IS_SUCCESS(ndr_err)) {
 182                 tevent_req_werror(req, DNS_ERR(SERVER_FAILURE));
 183                 return tevent_req_post(req, ev);
 184         }
 185         subreq = dns_udp_request_send(state, ev, forwarder, out_blob.data,
 186                                       out_blob.length);
 187         if (tevent_req_nomem(subreq, req)) {
 188                 return tevent_req_post(req, ev);
 189         }
 190         tevent_req_set_callback(subreq, ask_forwarder_done, req);
 191         return req;
 192 }
 193
 194 static void ask_forwarder_done(struct tevent_req *subreq)
 195 {
 196         struct tevent_req *req = tevent_req_callback_data(
 197                 subreq, struct tevent_req);
 198         struct ask_forwarder_state *state = tevent_req_data(
 199                 req, struct ask_forwarder_state);
 200         DATA_BLOB in_blob;
 201         enum ndr_err_code ndr_err;
 202         WERROR ret;
 203
 204         ret = dns_udp_request_recv(subreq, state,
 205                                    &in_blob.data, &in_blob.length);
 206         TALLOC_FREE(subreq);
 207         if (tevent_req_werror(req, ret)) {
 208                 return;
 209         }
 210
 211         ndr_err = ndr_pull_struct_blob(
 212                 &in_blob, state, &state->in_packet,
 213                 (ndr_pull_flags_fn_t)ndr_pull_dns_name_packet);
 214         if (!NDR_ERR_CODE_IS_SUCCESS(ndr_err)) {
 215                 tevent_req_werror(req, DNS_ERR(SERVER_FAILURE));
 216                 return;
 217         }
 218         if (state->in_packet.id != state->id) {
 219                 tevent_req_werror(req, DNS_ERR(NAME_ERROR));
 220                 return;
 221         }
 222         tevent_req_done(req);
 223 }
 224
 225 static WERROR ask_forwarder_recv(
 226         struct tevent_req *req, TALLOC_CTX *mem_ctx,
 227         struct dns_res_rec **answers, uint16_t *ancount,
 228         struct dns_res_rec **nsrecs, uint16_t *nscount,
 229         struct dns_res_rec **additional, uint16_t *arcount)
 230 {
 231         struct ask_forwarder_state *state = tevent_req_data(
 232                 req, struct ask_forwarder_state);
 233         struct dns_name_packet *in_packet = &state->in_packet;
 234         WERROR err;
 235
 236         if (tevent_req_is_werror(req, &err)) {
 237                 return err;
 238         }
 239
 240         *ancount = in_packet->ancount;
 241         *answers = talloc_move(mem_ctx, &in_packet->answers);
 242
 243         *nscount = in_packet->nscount;
 244         *nsrecs = talloc_move(mem_ctx, &in_packet->nsrecs);
 245
 246         *arcount = in_packet->arcount;
 247         *additional = talloc_move(mem_ctx, &in_packet->additional);
 248
 249         return WERR_OK;
 250 }
 251
 252 static WERROR handle_question(struct dns_server *dns,
 253                               TALLOC_CTX *mem_ctx,
 254                               const struct dns_name_question *question,
 255                               struct dns_res_rec **answers, uint16_t *ancount)
 256 {
 257         struct dns_res_rec *ans = *answers;
 258         WERROR werror, werror_return;
 259         unsigned int ri;
 260         struct dnsp_DnssrvRpcRecord *recs;
 261         uint16_t rec_count, ai = *ancount;
 262         struct ldb_dn *dn = NULL;
 263
 264         werror = dns_name2dn(dns, mem_ctx, question->name, &dn);
 265         W_ERROR_NOT_OK_RETURN(werror);
 266
 267         werror = dns_lookup_records(dns, mem_ctx, dn, &recs, &rec_count);
 268         W_ERROR_NOT_OK_RETURN(werror);
 269
 270         ans = talloc_realloc(mem_ctx, ans, struct dns_res_rec, rec_count + ai);
 271         if (ans == NULL) {
 272                 return WERR_NOMEM;
 273         }
 274
 275         /* Set up for an NXDOMAIN reply if no match is found */
 276         werror_return = DNS_ERR(NAME_ERROR);
 277
 278         for (ri = 0; ri < rec_count; ri++) {
 279                 if ((recs[ri].wType == DNS_TYPE_CNAME) &&
 280                     ((question->question_type == DNS_QTYPE_A) ||
 281                      (question->question_type == DNS_QTYPE_AAAA))) {
 282                         struct dns_name_question *new_q =
 283                                 talloc(mem_ctx, struct dns_name_question);
 284
 285                         if (new_q == NULL) {
 286                                 return WERR_NOMEM;
 287                         }
 288
 289                         /* We reply with one more record, so grow the array */
 290                         ans = talloc_realloc(mem_ctx, ans, struct dns_res_rec,
 291                                              rec_count + 1);
 292                         if (ans == NULL) {
 293                                 TALLOC_FREE(new_q);
 294                                 return WERR_NOMEM;
 295                         }
 296
 297                         /* First put in the CNAME record */
 298                         werror = create_response_rr(question, &recs[ri], &ans, &ai);
 299                         if (!W_ERROR_IS_OK(werror)) {
 300                                 return werror;
 301                         }
 302
 303                         /* And then look up the name it points at.. */
 304
 305                         /* First build up the new question */
 306                         new_q->question_type = question->question_type;
 307                         new_q->question_class = question->question_class;
 308                         if (new_q->question_type == DNS_QTYPE_A) {
 309                                 new_q->name = talloc_strdup(new_q, recs[ri].data.ipv4);
 310                         } else if (new_q->question_type == DNS_QTYPE_AAAA) {
 311                                 new_q->name = talloc_strdup(new_q, recs[ri].data.ipv6);
 312                         }
 313                         if (new_q->name == NULL) {
 314                                 TALLOC_FREE(new_q);
 315                                 return WERR_NOMEM;
 316                         }
 317                         /* and then call the lookup again */
 318                         werror = handle_question(dns, mem_ctx, new_q, &ans, &ai);
 319                         if (!W_ERROR_IS_OK(werror)) {
 320                                 return werror;
 321                         }
 322                         werror_return = WERR_OK;
 323
 324
 325                         continue;
 326                 }
 327                 if ((question->question_type != DNS_QTYPE_ALL) &&
 328                     (recs[ri].wType != question->question_type)) {
 329                         werror_return = WERR_OK;
 330                         continue;
 331                 }
 332                 werror = create_response_rr(question, &recs[ri], &ans, &ai);
 333                 if (!W_ERROR_IS_OK(werror)) {
 334                         return werror;
 335                 }
 336                 werror_return = WERR_OK;
 337         }
 338
 339         *ancount = ai;
 340         *answers = ans;
 341
 342         return werror_return;
 343 }
 344
 345 static NTSTATUS create_tkey(struct dns_server *dns,
 346                             const char* name,
 347                             const char* algorithm,
 348                             struct dns_server_tkey **tkey)
 349 {
 350         NTSTATUS status;
 351         struct dns_server_tkey_store *store = dns->tkeys;
 352         struct dns_server_tkey *k = talloc_zero(store, struct dns_server_tkey);
 353
 354         if (k == NULL) {
 355                 return NT_STATUS_NO_MEMORY;
 356         }
 357
 358         k->name = talloc_strdup(k, name);
 359
 360         if (k->name  == NULL) {
 361                 return NT_STATUS_NO_MEMORY;
 362         }
 363
 364         k->algorithm = talloc_strdup(k, algorithm);
 365         if (k->algorithm == NULL) {
 366                 return NT_STATUS_NO_MEMORY;
 367         }
 368
 369         status = samba_server_gensec_start(k,
 370                                            dns->task->event_ctx,
 371                                            dns->task->msg_ctx,
 372                                            dns->task->lp_ctx,
 373                                            dns->server_credentials,
 374                                            "dns",
 375                                            &k->gensec);
 376         if (!NT_STATUS_IS_OK(status)) {
 377                 DEBUG(1, ("Failed to start GENSEC server code: %s\n", nt_errstr(status)));
 378                 *tkey = NULL;
 379                 return status;
 380         }
 381
 382         gensec_want_feature(k->gensec, GENSEC_FEATURE_SIGN);
 383
 384         status = gensec_start_mech_by_oid(k->gensec, GENSEC_OID_SPNEGO);
 385
 386         if (!NT_STATUS_IS_OK(status)) {
 387                 DEBUG(1, ("Failed to start GENSEC server code: %s\n",
 388                           nt_errstr(status)));
 389                 *tkey = NULL;
 390                 return status;
 391         }
 392
 393         if (store->tkeys[store->next_idx] != NULL) {
 394                 TALLOC_FREE(store->tkeys[store->next_idx]);
 395         }
 396
 397         store->tkeys[store->next_idx] = k;
 398         (store->next_idx)++;
 399         store->next_idx %= store->size;
 400
 401         *tkey = k;
 402         return NT_STATUS_OK;
 403 }
 404
 405 static NTSTATUS accept_gss_ticket(TALLOC_CTX *mem_ctx,
 406                                   struct dns_server *dns,
 407                                   struct dns_server_tkey *tkey,
 408                                   const DATA_BLOB *key,
 409                                   DATA_BLOB *reply,
 410                                   uint16_t *dns_auth_error)
 411 {
 412         NTSTATUS status;
 413
 414         status = gensec_update(tkey->gensec, mem_ctx, dns->task->event_ctx,
 415                                *key, reply);
 416
 417         if (NT_STATUS_EQUAL(NT_STATUS_MORE_PROCESSING_REQUIRED, status)) {
 418                 *dns_auth_error = DNS_RCODE_OK;
 419                 return status;
 420         }
 421
 422         if (NT_STATUS_IS_OK(status)) {
 423
 424                 status = gensec_session_info(tkey->gensec, tkey, &tkey->session_info);
 425                 if (!NT_STATUS_IS_OK(status)) {
 426                         *dns_auth_error = DNS_RCODE_BADKEY;
 427                         return status;
 428                 }
 429                 *dns_auth_error = DNS_RCODE_OK;
 430         }
 431
 432         return status;
 433 }
 434
 435 static WERROR handle_tkey(struct dns_server *dns,
 436                           TALLOC_CTX *mem_ctx,
 437                           const struct dns_name_packet *in,
 438                           struct dns_request_state *state,
 439                           struct dns_res_rec **answers,
 440                           uint16_t *ancount)
 441 {
 442         struct dns_res_rec *in_tkey = NULL;
 443         struct dns_res_rec *ret_tkey;
 444         uint16_t i;
 445
 446         for (i = 0; i < in->arcount; i++) {
 447                 if (in->additional[i].rr_type == DNS_QTYPE_TKEY) {
 448                         in_tkey = &in->additional[i];
 449                         break;
 450                 }
 451         }
 452
 453         /* If this is a TKEY query, it should have a TKEY RR.
 454          * Behaviour is not really specified in RFC 2930 or RFC 3645, but
 455          * FORMAT_ERROR seems to be what BIND uses .*/
 456         if (in_tkey == NULL) {
 457                 return DNS_ERR(FORMAT_ERROR);
 458         }
 459
 460         ret_tkey = talloc_zero(mem_ctx, struct dns_res_rec);
 461         if (ret_tkey == NULL) {
 462                 return WERR_NOMEM;
 463         }
 464
 465         ret_tkey->name = talloc_strdup(ret_tkey, in_tkey->name);
 466         if (ret_tkey->name == NULL) {
 467                 return WERR_NOMEM;
 468         }
 469
 470         ret_tkey->rr_type = DNS_QTYPE_TKEY;
 471         ret_tkey->rr_class = DNS_QCLASS_ANY;
 472         ret_tkey->length = UINT16_MAX;
 473
 474         ret_tkey->rdata.tkey_record.algorithm = talloc_strdup(ret_tkey,
 475                         in_tkey->rdata.tkey_record.algorithm);
 476         if (ret_tkey->rdata.tkey_record.algorithm  == NULL) {
 477                 return WERR_NOMEM;
 478         }
 479
 480         ret_tkey->rdata.tkey_record.inception = in_tkey->rdata.tkey_record.inception;
 481         ret_tkey->rdata.tkey_record.expiration = in_tkey->rdata.tkey_record.expiration;
 482         ret_tkey->rdata.tkey_record.mode = in_tkey->rdata.tkey_record.mode;
 483
 484         switch (in_tkey->rdata.tkey_record.mode) {
 485         case DNS_TKEY_MODE_DH:
 486                 /* FIXME: According to RFC 2930, we MUST support this, but we don't.
 487                  * Still, claim it's a bad key instead of a bad mode */
 488                 ret_tkey->rdata.tkey_record.error = DNS_RCODE_BADKEY;
 489                 break;
 490         case DNS_TKEY_MODE_GSSAPI: {
 491                 NTSTATUS status;
 492                 struct dns_server_tkey *tkey;
 493                 DATA_BLOB key;
 494                 DATA_BLOB reply;
 495
 496                 tkey = dns_find_tkey(dns->tkeys, in->questions[0].name);
 497                 if (tkey != NULL && tkey->complete) {
 498                         /* TODO: check if the key is still valid */
 499                         DEBUG(1, ("Rejecting tkey negotiation for already established key\n"));
 500                         ret_tkey->rdata.tkey_record.error = DNS_RCODE_BADNAME;
 501                         break;
 502                 }
 503
 504                 if (tkey == NULL) {
 505                         status  = create_tkey(dns, in->questions[0].name,
 506                                               in_tkey->rdata.tkey_record.algorithm,
 507                                               &tkey);
 508                         if (!NT_STATUS_IS_OK(status)) {
 509                                 ret_tkey->rdata.tkey_record.error = DNS_RCODE_BADKEY;
 510                                 return ntstatus_to_werror(status);
 511                         }
 512                 }
 513
 514                 key.data = in_tkey->rdata.tkey_record.key_data;
 515                 key.length = in_tkey->rdata.tkey_record.key_size;
 516
 517                 status = accept_gss_ticket(ret_tkey, dns, tkey, &key, &reply,
 518                                            &ret_tkey->rdata.tkey_record.error);
 519                 if (NT_STATUS_EQUAL(status, NT_STATUS_MORE_PROCESSING_REQUIRED)) {
 520                         DEBUG(1, ("More processing required\n"));
 521                         ret_tkey->rdata.tkey_record.error = DNS_RCODE_BADKEY;
 522                 } else if (NT_STATUS_IS_OK(status)) {
 523                         DEBUG(1, ("Tkey handshake completed\n"));
 524                         ret_tkey->rdata.tkey_record.key_size = reply.length;
 525                         ret_tkey->rdata.tkey_record.key_data = talloc_memdup(ret_tkey,
 526                                                                 reply.data,
 527                                                                 reply.length);
 528                         state->sign = true;
 529                         state->key_name = talloc_strdup(mem_ctx, tkey->name);
 530                         if (state->key_name == NULL) {
 531                                 return WERR_NOMEM;
 532                         }
 533                 } else {
 534                         DEBUG(1, ("GSS key negotiation returned %s\n", nt_errstr(status)));
 535                         ret_tkey->rdata.tkey_record.error = DNS_RCODE_BADKEY;
 536                 }
 537
 538                 break;
 539                 }
 540         case DNS_TKEY_MODE_DELETE:
 541                 /* TODO: implement me */
 542                 DEBUG(1, ("Should delete tkey here\n"));
 543                 ret_tkey->rdata.tkey_record.error = DNS_RCODE_OK;
 544                 break;
 545         case DNS_TKEY_MODE_NULL:
 546         case DNS_TKEY_MODE_SERVER:
 547         case DNS_TKEY_MODE_CLIENT:
 548         case DNS_TKEY_MODE_LAST:
 549                 /* We don't have to implement these, return a mode error */
 550                 ret_tkey->rdata.tkey_record.error = DNS_RCODE_BADMODE;
 551                 break;
 552         default:
 553                 DEBUG(1, ("Unsupported TKEY mode %d\n",
 554                       in_tkey->rdata.tkey_record.mode));
 555         }
 556
 557         *answers = ret_tkey;
 558         *ancount = 1;
 559
 560         return WERR_OK;
 561 }
 562
 563 struct dns_server_process_query_state {
 564         struct dns_res_rec *answers;
 565         uint16_t ancount;
 566         struct dns_res_rec *nsrecs;
 567         uint16_t nscount;
 568         struct dns_res_rec *additional;
 569         uint16_t arcount;
 570 };
 571
 572 static void dns_server_process_query_got_response(struct tevent_req *subreq);
 573
 574 struct tevent_req *dns_server_process_query_send(
 575         TALLOC_CTX *mem_ctx, struct tevent_context *ev,
 576         struct dns_server *dns, struct dns_request_state *req_state,
 577         const struct dns_name_packet *in)
 578 {
 579         struct tevent_req *req, *subreq;
 580         struct dns_server_process_query_state *state;
 581
 582         req = tevent_req_create(mem_ctx, &state,
 583                                 struct dns_server_process_query_state);
 584         if (req == NULL) {
 585                 return NULL;
 586         }
 587         if (in->qdcount != 1) {
 588                 tevent_req_werror(req, DNS_ERR(FORMAT_ERROR));
 589                 return tevent_req_post(req, ev);
 590         }
 591
 592         /* Windows returns NOT_IMPLEMENTED on this as well */
 593         if (in->questions[0].question_class == DNS_QCLASS_NONE) {
 594                 tevent_req_werror(req, DNS_ERR(NOT_IMPLEMENTED));
 595                 return tevent_req_post(req, ev);
 596         }
 597
 598         if (in->questions[0].question_type == DNS_QTYPE_TKEY) {
 599                 WERROR err;
 600
 601                 err = handle_tkey(dns, state, in, req_state,
 602                                   &state->answers, &state->ancount);
 603                 if (tevent_req_werror(req, err)) {
 604                         return tevent_req_post(req, ev);
 605                 }
 606                 tevent_req_done(req);
 607                 return tevent_req_post(req, ev);
 608         }
 609
 610         if (dns_authorative_for_zone(dns, in->questions[0].name)) {
 611                 WERROR err;
 612
 613                 req_state->flags |= DNS_FLAG_AUTHORITATIVE;
 614                 err = handle_question(dns, state, &in->questions[0],
 615                                       &state->answers, &state->ancount);
 616                 if (tevent_req_werror(req, err)) {
 617                         return tevent_req_post(req, ev);
 618                 }
 619                 tevent_req_done(req);
 620                 return tevent_req_post(req, ev);
 621         }
 622
 623         if ((req_state->flags & DNS_FLAG_RECURSION_DESIRED) &&
 624             (req_state->flags & DNS_FLAG_RECURSION_AVAIL)) {
 625                 DEBUG(2, ("Not authoritative for '%s', forwarding\n",
 626                           in->questions[0].name));
 627
 628                 subreq = ask_forwarder_send(
 629                         dns,
 630                         state, ev, lpcfg_dns_forwarder(dns->task->lp_ctx),
 631                         &in->questions[0]);
 632                 if (tevent_req_nomem(subreq, req)) {
 633                         return tevent_req_post(req, ev);
 634                 }
 635                 tevent_req_set_callback(
 636                         subreq, dns_server_process_query_got_response, req);
 637                 return req;
 638         }
 639
 640         tevent_req_werror(req, DNS_ERR(NAME_ERROR));
 641         return tevent_req_post(req, ev);
 642 }
 643
 644 static void dns_server_process_query_got_response(struct tevent_req *subreq)
 645 {
 646         struct tevent_req *req = tevent_req_callback_data(
 647                 subreq, struct tevent_req);
 648         struct dns_server_process_query_state *state = tevent_req_data(
 649                 req, struct dns_server_process_query_state);
 650         WERROR err;
 651
 652         err = ask_forwarder_recv(subreq, state,
 653                                  &state->answers, &state->ancount,
 654                                  &state->nsrecs, &state->nscount,
 655                                  &state->additional, &state->arcount);
 656         TALLOC_FREE(subreq);
 657         if (tevent_req_werror(req, err)) {
 658                 return;
 659         }
 660         tevent_req_done(req);
 661 }
 662
 663 WERROR dns_server_process_query_recv(
 664         struct tevent_req *req, TALLOC_CTX *mem_ctx,
 665         struct dns_res_rec **answers,    uint16_t *ancount,
 666         struct dns_res_rec **nsrecs,     uint16_t *nscount,
 667         struct dns_res_rec **additional, uint16_t *arcount)
 668 {
 669         struct dns_server_process_query_state *state = tevent_req_data(
 670                 req, struct dns_server_process_query_state);
 671         WERROR err;
 672
 673         if (tevent_req_is_werror(req, &err)) {
 674                 return err;
 675         }
 676         *answers = talloc_move(mem_ctx, &state->answers);
 677         *ancount = state->ancount;
 678         *nsrecs = talloc_move(mem_ctx, &state->nsrecs);
 679         *nscount = state->nscount;
 680         *additional = talloc_move(mem_ctx, &state->additional);
 681         *arcount = state->arcount;
 682         return WERR_OK;
 683 }