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 #undef DBGC_CLASS
  41 #define DBGC_CLASS DBGC_DNS
  42
  43 static WERROR create_response_rr(const char *name,
  44                                  const struct dnsp_DnssrvRpcRecord *rec,
  45                                  struct dns_res_rec **answers, uint16_t *ancount)
  46 {
  47         struct dns_res_rec *ans = *answers;
  48         uint16_t ai = *ancount;
  49         char *tmp;
  50         uint32_t i;
  51
  52         ZERO_STRUCT(ans[ai]);
  53
  54         switch (rec->wType) {
  55         case DNS_QTYPE_CNAME:
  56                 ans[ai].rdata.cname_record = talloc_strdup(ans, rec->data.cname);
  57                 W_ERROR_HAVE_NO_MEMORY(ans[ai].rdata.cname_record);
  58                 break;
  59         case DNS_QTYPE_A:
  60                 ans[ai].rdata.ipv4_record = talloc_strdup(ans, rec->data.ipv4);
  61                 W_ERROR_HAVE_NO_MEMORY(ans[ai].rdata.ipv4_record);
  62                 break;
  63         case DNS_QTYPE_AAAA:
  64                 ans[ai].rdata.ipv6_record = talloc_strdup(ans, rec->data.ipv6);
  65                 W_ERROR_HAVE_NO_MEMORY(ans[ai].rdata.ipv6_record);
  66                 break;
  67         case DNS_TYPE_NS:
  68                 ans[ai].rdata.ns_record = talloc_strdup(ans, rec->data.ns);
  69                 W_ERROR_HAVE_NO_MEMORY(ans[ai].rdata.ns_record);
  70                 break;
  71         case DNS_QTYPE_SRV:
  72                 ans[ai].rdata.srv_record.priority = rec->data.srv.wPriority;
  73                 ans[ai].rdata.srv_record.weight   = rec->data.srv.wWeight;
  74                 ans[ai].rdata.srv_record.port     = rec->data.srv.wPort;
  75                 ans[ai].rdata.srv_record.target   = talloc_strdup(
  76                         ans, rec->data.srv.nameTarget);
  77                 W_ERROR_HAVE_NO_MEMORY(ans[ai].rdata.srv_record.target);
  78                 break;
  79         case DNS_QTYPE_SOA:
  80                 ans[ai].rdata.soa_record.mname   = talloc_strdup(
  81                         ans, rec->data.soa.mname);
  82                 W_ERROR_HAVE_NO_MEMORY(ans[ai].rdata.soa_record.mname);
  83                 ans[ai].rdata.soa_record.rname   = talloc_strdup(
  84                         ans, rec->data.soa.rname);
  85                 W_ERROR_HAVE_NO_MEMORY(ans[ai].rdata.soa_record.rname);
  86                 ans[ai].rdata.soa_record.serial  = rec->data.soa.serial;
  87                 ans[ai].rdata.soa_record.refresh = rec->data.soa.refresh;
  88                 ans[ai].rdata.soa_record.retry   = rec->data.soa.retry;
  89                 ans[ai].rdata.soa_record.expire  = rec->data.soa.expire;
  90                 ans[ai].rdata.soa_record.minimum = rec->data.soa.minimum;
  91                 break;
  92         case DNS_QTYPE_PTR:
  93                 ans[ai].rdata.ptr_record = talloc_strdup(ans, rec->data.ptr);
  94                 W_ERROR_HAVE_NO_MEMORY(ans[ai].rdata.ptr_record);
  95                 break;
  96         case DNS_QTYPE_MX:
  97                 ans[ai].rdata.mx_record.preference = rec->data.mx.wPriority;
  98                 ans[ai].rdata.mx_record.exchange = talloc_strdup(
  99                         ans, rec->data.mx.nameTarget);
 100                 if (ans[ai].rdata.mx_record.exchange == NULL) {
 101                         return WERR_NOMEM;
 102                 }
 103                 break;
 104         case DNS_QTYPE_TXT:
 105                 tmp = talloc_asprintf(ans, "\"%s\"", rec->data.txt.str[0]);
 106                 W_ERROR_HAVE_NO_MEMORY(tmp);
 107                 for (i=1; i<rec->data.txt.count; i++) {
 108                         tmp = talloc_asprintf_append_buffer(
 109                                 tmp, " \"%s\"", rec->data.txt.str[i]);
 110                         W_ERROR_HAVE_NO_MEMORY(tmp);
 111                 }
 112                 ans[ai].rdata.txt_record.txt = tmp;
 113                 break;
 114         default:
 115                 DEBUG(0, ("Got unhandled type %u query.\n", rec->wType));
 116                 return DNS_ERR(NOT_IMPLEMENTED);
 117         }
 118
 119         ans[ai].name = talloc_strdup(ans, name);
 120         W_ERROR_HAVE_NO_MEMORY(ans[ai].name);
 121         ans[ai].rr_type = rec->wType;
 122         ans[ai].rr_class = DNS_QCLASS_IN;
 123         ans[ai].ttl = rec->dwTtlSeconds;
 124         ans[ai].length = UINT16_MAX;
 125         ai++;
 126
 127         *answers = ans;
 128         *ancount = ai;
 129
 130         return WERR_OK;
 131 }
 132
 133 struct ask_forwarder_state {
 134         struct tevent_context *ev;
 135         uint16_t id;
 136         struct dns_name_packet in_packet;
 137 };
 138
 139 static void ask_forwarder_done(struct tevent_req *subreq);
 140
 141 static struct tevent_req *ask_forwarder_send(
 142         struct dns_server *dns,
 143         TALLOC_CTX *mem_ctx, struct tevent_context *ev,
 144         const char *forwarder, struct dns_name_question *question)
 145 {
 146         struct tevent_req *req, *subreq;
 147         struct ask_forwarder_state *state;
 148         struct dns_res_rec *options;
 149         struct dns_name_packet out_packet = { 0, };
 150         DATA_BLOB out_blob;
 151         enum ndr_err_code ndr_err;
 152         WERROR werr;
 153
 154         req = tevent_req_create(mem_ctx, &state, struct ask_forwarder_state);
 155         if (req == NULL) {
 156                 return NULL;
 157         }
 158         state->ev = ev;
 159         generate_random_buffer((uint8_t *)&state->id, sizeof(state->id));
 160
 161         if (!is_ipaddress(forwarder)) {
 162                 DEBUG(0, ("Invalid 'dns forwarder' setting '%s', needs to be "
 163                           "an IP address\n", forwarder));
 164                 tevent_req_werror(req, DNS_ERR(NAME_ERROR));
 165                 return tevent_req_post(req, ev);
 166         }
 167
 168         out_packet.id = state->id;
 169         out_packet.operation |= DNS_OPCODE_QUERY | DNS_FLAG_RECURSION_DESIRED;
 170         out_packet.qdcount = 1;
 171         out_packet.questions = question;
 172
 173         werr = dns_generate_options(dns, state, &options);
 174         if (!W_ERROR_IS_OK(werr)) {
 175                 tevent_req_werror(req, werr);
 176                 return tevent_req_post(req, ev);
 177         }
 178
 179         out_packet.arcount = 1;
 180         out_packet.additional = options;
 181
 182         ndr_err = ndr_push_struct_blob(
 183                 &out_blob, state, &out_packet,
 184                 (ndr_push_flags_fn_t)ndr_push_dns_name_packet);
 185         if (!NDR_ERR_CODE_IS_SUCCESS(ndr_err)) {
 186                 tevent_req_werror(req, DNS_ERR(SERVER_FAILURE));
 187                 return tevent_req_post(req, ev);
 188         }
 189         subreq = dns_udp_request_send(state, ev, forwarder, out_blob.data,
 190                                       out_blob.length);
 191         if (tevent_req_nomem(subreq, req)) {
 192                 return tevent_req_post(req, ev);
 193         }
 194         tevent_req_set_callback(subreq, ask_forwarder_done, req);
 195         return req;
 196 }
 197
 198 static void ask_forwarder_done(struct tevent_req *subreq)
 199 {
 200         struct tevent_req *req = tevent_req_callback_data(
 201                 subreq, struct tevent_req);
 202         struct ask_forwarder_state *state = tevent_req_data(
 203                 req, struct ask_forwarder_state);
 204         DATA_BLOB in_blob;
 205         enum ndr_err_code ndr_err;
 206         WERROR ret;
 207
 208         ret = dns_udp_request_recv(subreq, state,
 209                                    &in_blob.data, &in_blob.length);
 210         TALLOC_FREE(subreq);
 211         if (tevent_req_werror(req, ret)) {
 212                 return;
 213         }
 214
 215         ndr_err = ndr_pull_struct_blob(
 216                 &in_blob, state, &state->in_packet,
 217                 (ndr_pull_flags_fn_t)ndr_pull_dns_name_packet);
 218         if (!NDR_ERR_CODE_IS_SUCCESS(ndr_err)) {
 219                 tevent_req_werror(req, DNS_ERR(SERVER_FAILURE));
 220                 return;
 221         }
 222         if (state->in_packet.id != state->id) {
 223                 tevent_req_werror(req, DNS_ERR(NAME_ERROR));
 224                 return;
 225         }
 226         tevent_req_done(req);
 227 }
 228
 229 static WERROR ask_forwarder_recv(
 230         struct tevent_req *req, TALLOC_CTX *mem_ctx,
 231         struct dns_res_rec **answers, uint16_t *ancount,
 232         struct dns_res_rec **nsrecs, uint16_t *nscount,
 233         struct dns_res_rec **additional, uint16_t *arcount)
 234 {
 235         struct ask_forwarder_state *state = tevent_req_data(
 236                 req, struct ask_forwarder_state);
 237         struct dns_name_packet *in_packet = &state->in_packet;
 238         WERROR err;
 239
 240         if (tevent_req_is_werror(req, &err)) {
 241                 return err;
 242         }
 243
 244         *ancount = in_packet->ancount;
 245         *answers = talloc_move(mem_ctx, &in_packet->answers);
 246
 247         *nscount = in_packet->nscount;
 248         *nsrecs = talloc_move(mem_ctx, &in_packet->nsrecs);
 249
 250         *arcount = in_packet->arcount;
 251         *additional = talloc_move(mem_ctx, &in_packet->additional);
 252
 253         return WERR_OK;
 254 }
 255
 256 static WERROR add_zone_authority_record(struct dns_server *dns,
 257                                         TALLOC_CTX *mem_ctx,
 258                                         const struct dns_name_question *question,
 259                                         struct dns_res_rec **nsrecs, uint16_t *nscount)
 260 {
 261         const char *zone = NULL;
 262         struct dnsp_DnssrvRpcRecord *recs;
 263         struct dns_res_rec *ns = *nsrecs;
 264         uint16_t rec_count, ni = *nscount;
 265         struct ldb_dn *dn = NULL;
 266         unsigned int ri;
 267         WERROR werror;
 268
 269         zone = dns_get_authoritative_zone(dns, question->name);
 270         DEBUG(10, ("Creating zone authority record for '%s'\n", zone));
 271
 272         werror = dns_name2dn(dns, mem_ctx, zone, &dn);
 273         if (!W_ERROR_IS_OK(werror)) {
 274                 return werror;
 275         }
 276
 277         werror = dns_lookup_records(dns, mem_ctx, dn, &recs, &rec_count);
 278         if (!W_ERROR_IS_OK(werror)) {
 279                 return werror;
 280         }
 281
 282         ns = talloc_realloc(mem_ctx, ns, struct dns_res_rec, rec_count + ni);
 283         if (ns == NULL) {
 284                 return WERR_NOMEM;
 285         }
 286         for (ri = 0; ri < rec_count; ri++) {
 287                 if (recs[ri].wType == DNS_TYPE_SOA) {
 288                         werror = create_response_rr(zone, &recs[ri], &ns, &ni);
 289                         if (!W_ERROR_IS_OK(werror)) {
 290                                 return werror;
 291                         }
 292                 }
 293         }
 294
 295         *nscount = ni;
 296         *nsrecs = ns;
 297
 298         return WERR_OK;
 299 }
 300
 301
 302 static WERROR handle_question(struct dns_server *dns,
 303                               TALLOC_CTX *mem_ctx,
 304                               const struct dns_name_question *question,
 305                               struct dns_res_rec **answers, uint16_t *ancount,
 306                               struct dns_res_rec **nsrecs, uint16_t *nscount)
 307 {
 308         struct dns_res_rec *ans = *answers;
 309         struct dns_res_rec *ns = *nsrecs;
 310         WERROR werror, werror_return;
 311         unsigned int ri;
 312         struct dnsp_DnssrvRpcRecord *recs;
 313         uint16_t rec_count, ai = *ancount, ni = *nscount;
 314         struct ldb_dn *dn = NULL;
 315
 316         werror = dns_name2dn(dns, mem_ctx, question->name, &dn);
 317         if (!W_ERROR_IS_OK(werror)) {
 318                 return werror;
 319         }
 320
 321         werror = dns_lookup_records(dns, mem_ctx, dn, &recs, &rec_count);
 322         if (!W_ERROR_IS_OK(werror)) {
 323                 werror_return = werror;
 324                 goto done;
 325         }
 326
 327         ans = talloc_realloc(mem_ctx, ans, struct dns_res_rec, rec_count + ai);
 328         if (ans == NULL) {
 329                 return WERR_NOMEM;
 330         }
 331
 332         /* Set up for an NXDOMAIN reply if no match is found */
 333         werror_return = DNS_ERR(NAME_ERROR);
 334
 335         for (ri = 0; ri < rec_count; ri++) {
 336                 if ((recs[ri].wType == DNS_TYPE_CNAME) &&
 337                     ((question->question_type == DNS_QTYPE_A) ||
 338                      (question->question_type == DNS_QTYPE_AAAA))) {
 339                         struct dns_name_question *new_q =
 340                                 talloc(mem_ctx, struct dns_name_question);
 341
 342                         if (new_q == NULL) {
 343                                 return WERR_NOMEM;
 344                         }
 345
 346                         /* We reply with one more record, so grow the array */
 347                         ans = talloc_realloc(mem_ctx, ans, struct dns_res_rec,
 348                                              rec_count + 1);
 349                         if (ans == NULL) {
 350                                 TALLOC_FREE(new_q);
 351                                 return WERR_NOMEM;
 352                         }
 353
 354                         /* First put in the CNAME record */
 355                         werror = create_response_rr(question->name, &recs[ri], &ans, &ai);
 356                         if (!W_ERROR_IS_OK(werror)) {
 357                                 TALLOC_FREE(new_q);
 358                                 return werror;
 359                         }
 360
 361                         /* And then look up the name it points at.. */
 362
 363                         /* First build up the new question */
 364                         new_q->question_type = question->question_type;
 365                         new_q->question_class = question->question_class;
 366                         new_q->name = talloc_strdup(new_q, recs[ri].data.cname);
 367                         if (new_q->name == NULL) {
 368                                 TALLOC_FREE(new_q);
 369                                 return WERR_NOMEM;
 370                         }
 371                         /* and then call the lookup again */
 372                         werror = handle_question(dns, mem_ctx, new_q, &ans, &ai, &ns, &ni);
 373                         if (!W_ERROR_IS_OK(werror)) {
 374                                 goto done;
 375                         }
 376                         werror_return = WERR_OK;
 377
 378
 379                         continue;
 380                 }
 381                 if ((question->question_type != DNS_QTYPE_ALL) &&
 382                     (recs[ri].wType != (enum dns_record_type) question->question_type)) {
 383                         werror_return = WERR_OK;
 384                         continue;
 385                 }
 386                 werror = create_response_rr(question->name, &recs[ri], &ans, &ai);
 387                 if (!W_ERROR_IS_OK(werror)) {
 388                         return werror;
 389                 }
 390                 werror_return = WERR_OK;
 391         }
 392
 393 done:
 394         /* Always add an authority record to replies we should know about */
 395         add_zone_authority_record(dns, mem_ctx, question, &ns, &ni);
 396
 397         *ancount = ai;
 398         *answers = ans;
 399         *nscount = ni;
 400         *nsrecs = ns;
 401
 402         return werror_return;
 403 }
 404
 405 static NTSTATUS create_tkey(struct dns_server *dns,
 406                             const char* name,
 407                             const char* algorithm,
 408                             struct dns_server_tkey **tkey)
 409 {
 410         NTSTATUS status;
 411         struct dns_server_tkey_store *store = dns->tkeys;
 412         struct dns_server_tkey *k = talloc_zero(store, struct dns_server_tkey);
 413
 414         if (k == NULL) {
 415                 return NT_STATUS_NO_MEMORY;
 416         }
 417
 418         k->name = talloc_strdup(k, name);
 419
 420         if (k->name  == NULL) {
 421                 return NT_STATUS_NO_MEMORY;
 422         }
 423
 424         k->algorithm = talloc_strdup(k, algorithm);
 425         if (k->algorithm == NULL) {
 426                 return NT_STATUS_NO_MEMORY;
 427         }
 428
 429         status = samba_server_gensec_start(k,
 430                                            dns->task->event_ctx,
 431                                            dns->task->msg_ctx,
 432                                            dns->task->lp_ctx,
 433                                            dns->server_credentials,
 434                                            "dns",
 435                                            &k->gensec);
 436         if (!NT_STATUS_IS_OK(status)) {
 437                 DEBUG(1, ("Failed to start GENSEC server code: %s\n", nt_errstr(status)));
 438                 *tkey = NULL;
 439                 return status;
 440         }
 441
 442         gensec_want_feature(k->gensec, GENSEC_FEATURE_SIGN);
 443
 444         status = gensec_start_mech_by_oid(k->gensec, GENSEC_OID_SPNEGO);
 445
 446         if (!NT_STATUS_IS_OK(status)) {
 447                 DEBUG(1, ("Failed to start GENSEC server code: %s\n",
 448                           nt_errstr(status)));
 449                 *tkey = NULL;
 450                 return status;
 451         }
 452
 453         if (store->tkeys[store->next_idx] != NULL) {
 454                 TALLOC_FREE(store->tkeys[store->next_idx]);
 455         }
 456
 457         store->tkeys[store->next_idx] = k;
 458         (store->next_idx)++;
 459         store->next_idx %= store->size;
 460
 461         *tkey = k;
 462         return NT_STATUS_OK;
 463 }
 464
 465 static NTSTATUS accept_gss_ticket(TALLOC_CTX *mem_ctx,
 466                                   struct dns_server *dns,
 467                                   struct dns_server_tkey *tkey,
 468                                   const DATA_BLOB *key,
 469                                   DATA_BLOB *reply,
 470                                   uint16_t *dns_auth_error)
 471 {
 472         NTSTATUS status;
 473
 474         status = gensec_update_ev(tkey->gensec, mem_ctx, dns->task->event_ctx,
 475                                   *key, reply);
 476
 477         if (NT_STATUS_EQUAL(NT_STATUS_MORE_PROCESSING_REQUIRED, status)) {
 478                 *dns_auth_error = DNS_RCODE_OK;
 479                 return status;
 480         }
 481
 482         if (NT_STATUS_IS_OK(status)) {
 483
 484                 status = gensec_session_info(tkey->gensec, tkey, &tkey->session_info);
 485                 if (!NT_STATUS_IS_OK(status)) {
 486                         *dns_auth_error = DNS_RCODE_BADKEY;
 487                         return status;
 488                 }
 489                 *dns_auth_error = DNS_RCODE_OK;
 490         }
 491
 492         return status;
 493 }
 494
 495 static WERROR handle_tkey(struct dns_server *dns,
 496                           TALLOC_CTX *mem_ctx,
 497                           const struct dns_name_packet *in,
 498                           struct dns_request_state *state,
 499                           struct dns_res_rec **answers,
 500                           uint16_t *ancount)
 501 {
 502         struct dns_res_rec *in_tkey = NULL;
 503         struct dns_res_rec *ret_tkey;
 504         uint16_t i;
 505
 506         for (i = 0; i < in->arcount; i++) {
 507                 if (in->additional[i].rr_type == DNS_QTYPE_TKEY) {
 508                         in_tkey = &in->additional[i];
 509                         break;
 510                 }
 511         }
 512
 513         /* If this is a TKEY query, it should have a TKEY RR.
 514          * Behaviour is not really specified in RFC 2930 or RFC 3645, but
 515          * FORMAT_ERROR seems to be what BIND uses .*/
 516         if (in_tkey == NULL) {
 517                 return DNS_ERR(FORMAT_ERROR);
 518         }
 519
 520         ret_tkey = talloc_zero(mem_ctx, struct dns_res_rec);
 521         if (ret_tkey == NULL) {
 522                 return WERR_NOMEM;
 523         }
 524
 525         ret_tkey->name = talloc_strdup(ret_tkey, in_tkey->name);
 526         if (ret_tkey->name == NULL) {
 527                 return WERR_NOMEM;
 528         }
 529
 530         ret_tkey->rr_type = DNS_QTYPE_TKEY;
 531         ret_tkey->rr_class = DNS_QCLASS_ANY;
 532         ret_tkey->length = UINT16_MAX;
 533
 534         ret_tkey->rdata.tkey_record.algorithm = talloc_strdup(ret_tkey,
 535                         in_tkey->rdata.tkey_record.algorithm);
 536         if (ret_tkey->rdata.tkey_record.algorithm  == NULL) {
 537                 return WERR_NOMEM;
 538         }
 539
 540         ret_tkey->rdata.tkey_record.inception = in_tkey->rdata.tkey_record.inception;
 541         ret_tkey->rdata.tkey_record.expiration = in_tkey->rdata.tkey_record.expiration;
 542         ret_tkey->rdata.tkey_record.mode = in_tkey->rdata.tkey_record.mode;
 543
 544         switch (in_tkey->rdata.tkey_record.mode) {
 545         case DNS_TKEY_MODE_DH:
 546                 /* FIXME: According to RFC 2930, we MUST support this, but we don't.
 547                  * Still, claim it's a bad key instead of a bad mode */
 548                 ret_tkey->rdata.tkey_record.error = DNS_RCODE_BADKEY;
 549                 break;
 550         case DNS_TKEY_MODE_GSSAPI: {
 551                 NTSTATUS status;
 552                 struct dns_server_tkey *tkey;
 553                 DATA_BLOB key;
 554                 DATA_BLOB reply;
 555
 556                 tkey = dns_find_tkey(dns->tkeys, in->questions[0].name);
 557                 if (tkey != NULL && tkey->complete) {
 558                         /* TODO: check if the key is still valid */
 559                         DEBUG(1, ("Rejecting tkey negotiation for already established key\n"));
 560                         ret_tkey->rdata.tkey_record.error = DNS_RCODE_BADNAME;
 561                         break;
 562                 }
 563
 564                 if (tkey == NULL) {
 565                         status  = create_tkey(dns, in->questions[0].name,
 566                                               in_tkey->rdata.tkey_record.algorithm,
 567                                               &tkey);
 568                         if (!NT_STATUS_IS_OK(status)) {
 569                                 ret_tkey->rdata.tkey_record.error = DNS_RCODE_BADKEY;
 570                                 return ntstatus_to_werror(status);
 571                         }
 572                 }
 573
 574                 key.data = in_tkey->rdata.tkey_record.key_data;
 575                 key.length = in_tkey->rdata.tkey_record.key_size;
 576
 577                 status = accept_gss_ticket(ret_tkey, dns, tkey, &key, &reply,
 578                                            &ret_tkey->rdata.tkey_record.error);
 579                 if (NT_STATUS_EQUAL(status, NT_STATUS_MORE_PROCESSING_REQUIRED)) {
 580                         DEBUG(1, ("More processing required\n"));
 581                         ret_tkey->rdata.tkey_record.error = DNS_RCODE_BADKEY;
 582                 } else if (NT_STATUS_IS_OK(status)) {
 583                         DEBUG(1, ("Tkey handshake completed\n"));
 584                         ret_tkey->rdata.tkey_record.key_size = reply.length;
 585                         ret_tkey->rdata.tkey_record.key_data = talloc_memdup(ret_tkey,
 586                                                                 reply.data,
 587                                                                 reply.length);
 588                         state->sign = true;
 589                         state->key_name = talloc_strdup(state->mem_ctx, tkey->name);
 590                         if (state->key_name == NULL) {
 591                                 return WERR_NOMEM;
 592                         }
 593                 } else {
 594                         DEBUG(1, ("GSS key negotiation returned %s\n", nt_errstr(status)));
 595                         ret_tkey->rdata.tkey_record.error = DNS_RCODE_BADKEY;
 596                 }
 597
 598                 break;
 599                 }
 600         case DNS_TKEY_MODE_DELETE:
 601                 /* TODO: implement me */
 602                 DEBUG(1, ("Should delete tkey here\n"));
 603                 ret_tkey->rdata.tkey_record.error = DNS_RCODE_OK;
 604                 break;
 605         case DNS_TKEY_MODE_NULL:
 606         case DNS_TKEY_MODE_SERVER:
 607         case DNS_TKEY_MODE_CLIENT:
 608         case DNS_TKEY_MODE_LAST:
 609                 /* We don't have to implement these, return a mode error */
 610                 ret_tkey->rdata.tkey_record.error = DNS_RCODE_BADMODE;
 611                 break;
 612         default:
 613                 DEBUG(1, ("Unsupported TKEY mode %d\n",
 614                       in_tkey->rdata.tkey_record.mode));
 615         }
 616
 617         *answers = ret_tkey;
 618         *ancount = 1;
 619
 620         return WERR_OK;
 621 }
 622
 623 struct dns_server_process_query_state {
 624         struct dns_res_rec *answers;
 625         uint16_t ancount;
 626         struct dns_res_rec *nsrecs;
 627         uint16_t nscount;
 628         struct dns_res_rec *additional;
 629         uint16_t arcount;
 630 };
 631
 632 static void dns_server_process_query_got_response(struct tevent_req *subreq);
 633
 634 struct tevent_req *dns_server_process_query_send(
 635         TALLOC_CTX *mem_ctx, struct tevent_context *ev,
 636         struct dns_server *dns, struct dns_request_state *req_state,
 637         const struct dns_name_packet *in)
 638 {
 639         struct tevent_req *req, *subreq;
 640         struct dns_server_process_query_state *state;
 641
 642         req = tevent_req_create(mem_ctx, &state,
 643                                 struct dns_server_process_query_state);
 644         if (req == NULL) {
 645                 return NULL;
 646         }
 647         if (in->qdcount != 1) {
 648                 tevent_req_werror(req, DNS_ERR(FORMAT_ERROR));
 649                 return tevent_req_post(req, ev);
 650         }
 651
 652         /* Windows returns NOT_IMPLEMENTED on this as well */
 653         if (in->questions[0].question_class == DNS_QCLASS_NONE) {
 654                 tevent_req_werror(req, DNS_ERR(NOT_IMPLEMENTED));
 655                 return tevent_req_post(req, ev);
 656         }
 657
 658         if (in->questions[0].question_type == DNS_QTYPE_TKEY) {
 659                 WERROR err;
 660
 661                 err = handle_tkey(dns, state, in, req_state,
 662                                   &state->answers, &state->ancount);
 663                 if (tevent_req_werror(req, err)) {
 664                         return tevent_req_post(req, ev);
 665                 }
 666                 tevent_req_done(req);
 667                 return tevent_req_post(req, ev);
 668         }
 669
 670         if (dns_authorative_for_zone(dns, in->questions[0].name)) {
 671                 WERROR err;
 672
 673                 req_state->flags |= DNS_FLAG_AUTHORITATIVE;
 674                 err = handle_question(dns, state, &in->questions[0],
 675                                       &state->answers, &state->ancount,
 676                                       &state->nsrecs, &state->nscount);
 677
 678                 if (W_ERROR_EQUAL(err, DNS_ERR(NAME_ERROR))) {
 679                         err = WERR_OK;
 680                 }
 681
 682                 if (tevent_req_werror(req, err)) {
 683                         return tevent_req_post(req, ev);
 684                 }
 685
 686                 tevent_req_done(req);
 687                 return tevent_req_post(req, ev);
 688         }
 689
 690         if ((req_state->flags & DNS_FLAG_RECURSION_DESIRED) &&
 691             (req_state->flags & DNS_FLAG_RECURSION_AVAIL)) {
 692                 DEBUG(2, ("Not authoritative for '%s', forwarding\n",
 693                           in->questions[0].name));
 694
 695                 subreq = ask_forwarder_send(
 696                         dns,
 697                         state, ev, lpcfg_dns_forwarder(dns->task->lp_ctx),
 698                         &in->questions[0]);
 699                 if (tevent_req_nomem(subreq, req)) {
 700                         return tevent_req_post(req, ev);
 701                 }
 702                 tevent_req_set_callback(
 703                         subreq, dns_server_process_query_got_response, req);
 704                 return req;
 705         }
 706
 707         tevent_req_werror(req, DNS_ERR(NAME_ERROR));
 708         return tevent_req_post(req, ev);
 709 }
 710
 711 static void dns_server_process_query_got_response(struct tevent_req *subreq)
 712 {
 713         struct tevent_req *req = tevent_req_callback_data(
 714                 subreq, struct tevent_req);
 715         struct dns_server_process_query_state *state = tevent_req_data(
 716                 req, struct dns_server_process_query_state);
 717         WERROR err;
 718
 719         err = ask_forwarder_recv(subreq, state,
 720                                  &state->answers, &state->ancount,
 721                                  &state->nsrecs, &state->nscount,
 722                                  &state->additional, &state->arcount);
 723         TALLOC_FREE(subreq);
 724         if (tevent_req_werror(req, err)) {
 725                 return;
 726         }
 727         tevent_req_done(req);
 728 }
 729
 730 WERROR dns_server_process_query_recv(
 731         struct tevent_req *req, TALLOC_CTX *mem_ctx,
 732         struct dns_res_rec **answers,    uint16_t *ancount,
 733         struct dns_res_rec **nsrecs,     uint16_t *nscount,
 734         struct dns_res_rec **additional, uint16_t *arcount)
 735 {
 736         struct dns_server_process_query_state *state = tevent_req_data(
 737                 req, struct dns_server_process_query_state);
 738         WERROR err = WERR_OK;
 739
 740         if (tevent_req_is_werror(req, &err)) {
 741
 742                 if ((!W_ERROR_EQUAL(err, DNS_ERR(NAME_ERROR))) &&
 743                     (!W_ERROR_EQUAL(err, WERR_DNS_ERROR_NAME_DOES_NOT_EXIST))) {
 744                         return err;
 745                 }
 746         }
 747         *answers = talloc_move(mem_ctx, &state->answers);
 748         *ancount = state->ancount;
 749         *nsrecs = talloc_move(mem_ctx, &state->nsrecs);
 750         *nscount = state->nscount;
 751         *additional = talloc_move(mem_ctx, &state->additional);
 752         *arcount = state->arcount;
 753         return err;
 754 }