dns: Use new DNS debugclass in DNS server
[kai/samba.git] / source4 / dns_server / dns_query.c
index 3564140948b3809e30542f7b2c94ae23238ea5b0..4ad14b9a558810e07f2590d66df762fc5545ecd8 100644 (file)
 #include "dns_server/dns_server.h"
 #include "libcli/dns/libdns.h"
 #include "lib/util/util_net.h"
+#include "lib/util/tevent_werror.h"
+#include "auth/auth.h"
+#include "auth/credentials/credentials.h"
+#include "auth/gensec/gensec.h"
+
+#undef DBGC_CLASS
+#define DBGC_CLASS DBGC_DNS
 
 static WERROR create_response_rr(const struct dns_name_question *question,
                                 const struct dnsp_DnssrvRpcRecord *rec,
@@ -47,21 +54,19 @@ static WERROR create_response_rr(const struct dns_name_question *question,
        switch (rec->wType) {
        case DNS_QTYPE_CNAME:
                ans[ai].rdata.cname_record = talloc_strdup(ans, rec->data.cname);
-               if (ans[ai].rdata.cname_record == NULL) {
-                       return WERR_NOMEM;
-               }
+               W_ERROR_HAVE_NO_MEMORY(ans[ai].rdata.cname_record);
                break;
        case DNS_QTYPE_A:
                ans[ai].rdata.ipv4_record = talloc_strdup(ans, rec->data.ipv4);
-               if (ans[ai].rdata.ipv4_record == NULL) {
-                       return WERR_NOMEM;
-               }
+               W_ERROR_HAVE_NO_MEMORY(ans[ai].rdata.ipv4_record);
                break;
        case DNS_QTYPE_AAAA:
-               ans[ai].rdata.ipv6_record = rec->data.ipv6;
+               ans[ai].rdata.ipv6_record = talloc_strdup(ans, rec->data.ipv6);
+               W_ERROR_HAVE_NO_MEMORY(ans[ai].rdata.ipv6_record);
                break;
        case DNS_TYPE_NS:
-               ans[ai].rdata.ns_record = rec->data.ns;
+               ans[ai].rdata.ns_record = talloc_strdup(ans, rec->data.ns);
+               W_ERROR_HAVE_NO_MEMORY(ans[ai].rdata.ns_record);
                break;
        case DNS_QTYPE_SRV:
                ans[ai].rdata.srv_record.priority = rec->data.srv.wPriority;
@@ -69,21 +74,15 @@ static WERROR create_response_rr(const struct dns_name_question *question,
                ans[ai].rdata.srv_record.port     = rec->data.srv.wPort;
                ans[ai].rdata.srv_record.target   = talloc_strdup(
                        ans, rec->data.srv.nameTarget);
-               if (ans[ai].rdata.srv_record.target == NULL) {
-                       return WERR_NOMEM;
-               }
+               W_ERROR_HAVE_NO_MEMORY(ans[ai].rdata.srv_record.target);
                break;
        case DNS_QTYPE_SOA:
                ans[ai].rdata.soa_record.mname   = talloc_strdup(
                        ans, rec->data.soa.mname);
-               if (ans[ai].rdata.soa_record.mname == NULL) {
-                       return WERR_NOMEM;
-               }
+               W_ERROR_HAVE_NO_MEMORY(ans[ai].rdata.soa_record.mname);
                ans[ai].rdata.soa_record.rname   = talloc_strdup(
                        ans, rec->data.soa.rname);
-               if (ans[ai].rdata.soa_record.rname == NULL) {
-                       return WERR_NOMEM;
-               }
+               W_ERROR_HAVE_NO_MEMORY(ans[ai].rdata.soa_record.rname);
                ans[ai].rdata.soa_record.serial  = rec->data.soa.serial;
                ans[ai].rdata.soa_record.refresh = rec->data.soa.refresh;
                ans[ai].rdata.soa_record.retry   = rec->data.soa.retry;
@@ -93,17 +92,21 @@ static WERROR create_response_rr(const struct dns_name_question *question,
        case DNS_QTYPE_PTR:
                ans[ai].rdata.ptr_record = talloc_strdup(ans, rec->data.ptr);
                break;
-       case DNS_QTYPE_TXT:
-               tmp = talloc_asprintf(ans, "\"%s\"", rec->data.txt.str[0]);
-               if (tmp == NULL) {
+       case DNS_QTYPE_MX:
+               ans[ai].rdata.mx_record.preference = rec->data.mx.wPriority;
+               ans[ai].rdata.mx_record.exchange = talloc_strdup(
+                       ans, rec->data.mx.nameTarget);
+               if (ans[ai].rdata.mx_record.exchange == NULL) {
                        return WERR_NOMEM;
                }
+               break;
+       case DNS_QTYPE_TXT:
+               tmp = talloc_asprintf(ans, "\"%s\"", rec->data.txt.str[0]);
+               W_ERROR_HAVE_NO_MEMORY(tmp);
                for (i=1; i<rec->data.txt.count; i++) {
                        tmp = talloc_asprintf_append_buffer(
                                tmp, " \"%s\"", rec->data.txt.str[i]);
-                       if (tmp == NULL) {
-                               return WERR_NOMEM;
-                       }
+                       W_ERROR_HAVE_NO_MEMORY(tmp);
                }
                ans[ai].rdata.txt_record.txt = tmp;
                break;
@@ -113,9 +116,7 @@ static WERROR create_response_rr(const struct dns_name_question *question,
        }
 
        ans[ai].name = talloc_strdup(ans, question->name);
-       if (ans[ai].name == NULL) {
-               return WERR_NOMEM;
-       }
+       W_ERROR_HAVE_NO_MEMORY(ans[ai].name);
        ans[ai].rr_type = rec->wType;
        ans[ai].rr_class = DNS_QCLASS_IN;
        ans[ai].ttl = rec->dwTtlSeconds;
@@ -128,66 +129,103 @@ static WERROR create_response_rr(const struct dns_name_question *question,
        return WERR_OK;
 }
 
-static WERROR ask_forwarder(struct dns_server *dns,
-                           TALLOC_CTX *mem_ctx,
-                           struct dns_name_question *question,
-                           struct dns_res_rec **answers, uint16_t *ancount,
-                           struct dns_res_rec **nsrecs, uint16_t *nscount,
-                           struct dns_res_rec **additional, uint16_t *arcount)
+struct ask_forwarder_state {
+       struct tevent_context *ev;
+       uint16_t id;
+       struct dns_name_packet in_packet;
+};
+
+static void ask_forwarder_done(struct tevent_req *subreq);
+
+static struct tevent_req *ask_forwarder_send(
+       TALLOC_CTX *mem_ctx, struct tevent_context *ev,
+       const char *forwarder, struct dns_name_question *question)
 {
-       struct tevent_context *ev = tevent_context_init(mem_ctx);
-       struct dns_name_packet *out_packet, *in_packet;
-       uint16_t id = random();
-       DATA_BLOB out, in;
+       struct tevent_req *req, *subreq;
+       struct ask_forwarder_state *state;
+       struct dns_name_packet out_packet = { 0, };
+       DATA_BLOB out_blob;
        enum ndr_err_code ndr_err;
-       WERROR werr = WERR_OK;
-       struct tevent_req *req;
-       const char *forwarder = lpcfg_dns_forwarder(dns->task->lp_ctx);
+
+       req = tevent_req_create(mem_ctx, &state, struct ask_forwarder_state);
+       if (req == NULL) {
+               return NULL;
+       }
+       state->ev = ev;
+       generate_random_buffer((uint8_t *)&state->id, sizeof(state->id));
 
        if (!is_ipaddress(forwarder)) {
                DEBUG(0, ("Invalid 'dns forwarder' setting '%s', needs to be "
                          "an IP address\n", forwarder));
-               return DNS_ERR(NAME_ERROR);
+               tevent_req_werror(req, DNS_ERR(NAME_ERROR));
+               return tevent_req_post(req, ev);
        }
 
-       out_packet = talloc_zero(mem_ctx, struct dns_name_packet);
-       W_ERROR_HAVE_NO_MEMORY(out_packet);
+       out_packet.id = state->id;
+       out_packet.operation |= DNS_OPCODE_QUERY | DNS_FLAG_RECURSION_DESIRED;
+       out_packet.qdcount = 1;
+       out_packet.questions = question;
 
-       out_packet->id = id;
-       out_packet->operation |= DNS_OPCODE_QUERY | DNS_FLAG_RECURSION_DESIRED;
-
-       out_packet->qdcount = 1;
-       out_packet->questions = question;
-
-       ndr_err = ndr_push_struct_blob(&out, mem_ctx, out_packet,
-                       (ndr_push_flags_fn_t)ndr_push_dns_name_packet);
+       ndr_err = ndr_push_struct_blob(
+               &out_blob, state, &out_packet,
+               (ndr_push_flags_fn_t)ndr_push_dns_name_packet);
        if (!NDR_ERR_CODE_IS_SUCCESS(ndr_err)) {
-               return DNS_ERR(SERVER_FAILURE);
+               tevent_req_werror(req, DNS_ERR(SERVER_FAILURE));
+               return tevent_req_post(req, ev);
        }
-
-       req = dns_udp_request_send(mem_ctx, ev, forwarder, out.data, out.length);
-       W_ERROR_HAVE_NO_MEMORY(req);
-
-       if(!tevent_req_poll(req, ev)) {
-               return DNS_ERR(SERVER_FAILURE);
+       subreq = dns_udp_request_send(state, ev, forwarder, out_blob.data,
+                                     out_blob.length);
+       if (tevent_req_nomem(subreq, req)) {
+               return tevent_req_post(req, ev);
        }
+       tevent_req_set_callback(subreq, ask_forwarder_done, req);
+       return req;
+}
 
-       werr = dns_udp_request_recv(req, mem_ctx, &in.data, &in.length);
-       W_ERROR_NOT_OK_RETURN(werr);
+static void ask_forwarder_done(struct tevent_req *subreq)
+{
+       struct tevent_req *req = tevent_req_callback_data(
+               subreq, struct tevent_req);
+       struct ask_forwarder_state *state = tevent_req_data(
+               req, struct ask_forwarder_state);
+       DATA_BLOB in_blob;
+       enum ndr_err_code ndr_err;
+       WERROR ret;
 
-       in_packet = talloc_zero(mem_ctx, struct dns_name_packet);
-       W_ERROR_HAVE_NO_MEMORY(in_packet);
+       ret = dns_udp_request_recv(subreq, state,
+                                  &in_blob.data, &in_blob.length);
+       TALLOC_FREE(subreq);
+       if (tevent_req_werror(req, ret)) {
+               return;
+       }
 
-       ndr_err = ndr_pull_struct_blob(&in, in_packet, in_packet,
-                       (ndr_pull_flags_fn_t)ndr_pull_dns_name_packet);
+       ndr_err = ndr_pull_struct_blob(
+               &in_blob, state, &state->in_packet,
+               (ndr_pull_flags_fn_t)ndr_pull_dns_name_packet);
        if (!NDR_ERR_CODE_IS_SUCCESS(ndr_err)) {
-               return DNS_ERR(SERVER_FAILURE);
+               tevent_req_werror(req, DNS_ERR(SERVER_FAILURE));
+               return;
        }
+       if (state->in_packet.id != state->id) {
+               tevent_req_werror(req, DNS_ERR(NAME_ERROR));
+               return;
+       }
+       tevent_req_done(req);
+}
 
-       if (in_packet->id != id) {
-               DEBUG(0, ("DNS packet id mismatch: 0x%0x, expected 0x%0x\n",
-                         in_packet->id, id));
-               return DNS_ERR(NAME_ERROR);
+static WERROR ask_forwarder_recv(
+       struct tevent_req *req, TALLOC_CTX *mem_ctx,
+       struct dns_res_rec **answers, uint16_t *ancount,
+       struct dns_res_rec **nsrecs, uint16_t *nscount,
+       struct dns_res_rec **additional, uint16_t *arcount)
+{
+       struct ask_forwarder_state *state = tevent_req_data(
+               req, struct ask_forwarder_state);
+       struct dns_name_packet *in_packet = &state->in_packet;
+       WERROR err;
+
+       if (tevent_req_is_werror(req, &err)) {
+               return err;
        }
 
        *ancount = in_packet->ancount;
@@ -199,7 +237,7 @@ static WERROR ask_forwarder(struct dns_server *dns,
        *arcount = in_packet->arcount;
        *additional = talloc_move(mem_ctx, &in_packet->additional);
 
-       return werr;
+       return WERR_OK;
 }
 
 static WERROR handle_question(struct dns_server *dns,
@@ -207,11 +245,11 @@ static WERROR handle_question(struct dns_server *dns,
                              const struct dns_name_question *question,
                              struct dns_res_rec **answers, uint16_t *ancount)
 {
-       struct dns_res_rec *ans;
+       struct dns_res_rec *ans = *answers;
        WERROR werror;
        unsigned int ri;
        struct dnsp_DnssrvRpcRecord *recs;
-       uint16_t rec_count, ai = 0;
+       uint16_t rec_count, ai = *ancount;
        struct ldb_dn *dn = NULL;
 
        werror = dns_name2dn(dns, mem_ctx, question->name, &dn);
@@ -220,16 +258,67 @@ static WERROR handle_question(struct dns_server *dns,
        werror = dns_lookup_records(dns, mem_ctx, dn, &recs, &rec_count);
        W_ERROR_NOT_OK_RETURN(werror);
 
-       ans = talloc_zero_array(mem_ctx, struct dns_res_rec, rec_count);
-       W_ERROR_HAVE_NO_MEMORY(ans);
+       ans = talloc_realloc(mem_ctx, ans, struct dns_res_rec, rec_count + ai);
+       if (ans == NULL) {
+               return WERR_NOMEM;
+       }
 
        for (ri = 0; ri < rec_count; ri++) {
+               if ((recs[ri].wType == DNS_TYPE_CNAME) &&
+                   ((question->question_type == DNS_QTYPE_A) ||
+                    (question->question_type == DNS_QTYPE_AAAA))) {
+                       struct dns_name_question *new_q =
+                               talloc(mem_ctx, struct dns_name_question);
+
+                       if (new_q == NULL) {
+                               return WERR_NOMEM;
+                       }
+
+                       /* We reply with one more record, so grow the array */
+                       ans = talloc_realloc(mem_ctx, ans, struct dns_res_rec,
+                                            rec_count + 1);
+                       if (ans == NULL) {
+                               TALLOC_FREE(new_q);
+                               return WERR_NOMEM;
+                       }
+
+                       /* First put in the CNAME record */
+                       werror = create_response_rr(question, &recs[ri], &ans, &ai);
+                       if (!W_ERROR_IS_OK(werror)) {
+                               return werror;
+                       }
+
+                       /* And then look up the name it points at.. */
+
+                       /* First build up the new question */
+                       new_q->question_type = question->question_type;
+                       new_q->question_class = question->question_class;
+                       if (new_q->question_type == DNS_QTYPE_A) {
+                               new_q->name = talloc_strdup(new_q, recs[ri].data.ipv4);
+                       } else if (new_q->question_type == DNS_QTYPE_AAAA) {
+                               new_q->name = talloc_strdup(new_q, recs[ri].data.ipv6);
+                       }
+                       if (new_q->name == NULL) {
+                               TALLOC_FREE(new_q);
+                               return WERR_NOMEM;
+                       }
+                       /* and then call the lookup again */
+                       werror = handle_question(dns, mem_ctx, new_q, &ans, &ai);
+                       if (!W_ERROR_IS_OK(werror)) {
+                               return werror;
+                       }
+
+
+                       continue;
+               }
                if ((question->question_type != DNS_QTYPE_ALL) &&
                    (recs[ri].wType != question->question_type)) {
                        continue;
                }
                werror = create_response_rr(question, &recs[ri], &ans, &ai);
-               W_ERROR_NOT_OK_RETURN(werror);
+               if (!W_ERROR_IS_OK(werror)) {
+                       return werror;
+               }
        }
 
        if (ai == 0) {
@@ -240,62 +329,343 @@ static WERROR handle_question(struct dns_server *dns,
        *answers = ans;
 
        return WERR_OK;
+}
+
+static NTSTATUS create_tkey(struct dns_server *dns,
+                           const char* name,
+                           const char* algorithm,
+                           struct dns_server_tkey **tkey)
+{
+       NTSTATUS status;
+       struct dns_server_tkey_store *store = dns->tkeys;
+       struct dns_server_tkey *k = talloc_zero(store, struct dns_server_tkey);
+
+       if (k == NULL) {
+               return NT_STATUS_NO_MEMORY;
+       }
+
+       k->name = talloc_strdup(k, name);
+
+       if (k->name  == NULL) {
+               return NT_STATUS_NO_MEMORY;
+       }
+
+       k->algorithm = talloc_strdup(k, algorithm);
+       if (k->algorithm == NULL) {
+               return NT_STATUS_NO_MEMORY;
+       }
+
+       status = samba_server_gensec_start(k,
+                                          dns->task->event_ctx,
+                                          dns->task->msg_ctx,
+                                          dns->task->lp_ctx,
+                                          dns->server_credentials,
+                                          "dns",
+                                          &k->gensec);
+       if (!NT_STATUS_IS_OK(status)) {
+               DEBUG(1, ("Failed to start GENSEC server code: %s\n", nt_errstr(status)));
+               *tkey = NULL;
+               return status;
+       }
+
+       gensec_want_feature(k->gensec, GENSEC_FEATURE_SIGN);
+
+       status = gensec_start_mech_by_oid(k->gensec, GENSEC_OID_SPNEGO);
+
+       if (!NT_STATUS_IS_OK(status)) {
+               DEBUG(1, ("Failed to start GENSEC server code: %s\n",
+                         nt_errstr(status)));
+               *tkey = NULL;
+               return status;
+       }
 
+       if (store->tkeys[store->next_idx] != NULL) {
+               TALLOC_FREE(store->tkeys[store->next_idx]);
+       }
+
+       store->tkeys[store->next_idx] = k;
+       (store->next_idx)++;
+       store->next_idx %= store->size;
+
+       *tkey = k;
+       return NT_STATUS_OK;
 }
 
-WERROR dns_server_process_query(struct dns_server *dns,
-                               struct dns_request_state *state,
-                               TALLOC_CTX *mem_ctx,
-                               struct dns_name_packet *in,
-                               struct dns_res_rec **answers,    uint16_t *ancount,
-                               struct dns_res_rec **nsrecs,     uint16_t *nscount,
-                               struct dns_res_rec **additional, uint16_t *arcount)
+static NTSTATUS accept_gss_ticket(TALLOC_CTX *mem_ctx,
+                                 struct dns_server *dns,
+                                 struct dns_server_tkey *tkey,
+                                 const DATA_BLOB *key,
+                                 DATA_BLOB *reply,
+                                 uint16_t *dns_auth_error)
 {
-       uint16_t num_answers=0, num_nsrecs=0, num_additional=0;
-       struct dns_res_rec *ans=NULL, *ns=NULL, *adds=NULL;
-       WERROR werror;
+       NTSTATUS status;
 
-       if (in->qdcount != 1) {
+       status = gensec_update(tkey->gensec, mem_ctx, dns->task->event_ctx,
+                              *key, reply);
+
+       if (NT_STATUS_EQUAL(NT_STATUS_MORE_PROCESSING_REQUIRED, status)) {
+               *dns_auth_error = DNS_RCODE_OK;
+               return status;
+       }
+
+       if (NT_STATUS_IS_OK(status)) {
+
+               status = gensec_session_info(tkey->gensec, tkey, &tkey->session_info);
+               if (!NT_STATUS_IS_OK(status)) {
+                       *dns_auth_error = DNS_RCODE_BADKEY;
+                       return status;
+               }
+               *dns_auth_error = DNS_RCODE_OK;
+       }
+
+       return status;
+}
+
+static WERROR handle_tkey(struct dns_server *dns,
+                          TALLOC_CTX *mem_ctx,
+                          const struct dns_name_packet *in,
+                         struct dns_request_state *state,
+                          struct dns_res_rec **answers,
+                          uint16_t *ancount)
+{
+       struct dns_res_rec *in_tkey = NULL;
+       struct dns_res_rec *ret_tkey;
+       uint16_t i;
+
+       for (i = 0; i < in->arcount; i++) {
+               if (in->additional[i].rr_type == DNS_QTYPE_TKEY) {
+                       in_tkey = &in->additional[i];
+                       break;
+               }
+       }
+
+       /* If this is a TKEY query, it should have a TKEY RR.
+        * Behaviour is not really specified in RFC 2930 or RFC 3645, but
+        * FORMAT_ERROR seems to be what BIND uses .*/
+       if (in_tkey == NULL) {
                return DNS_ERR(FORMAT_ERROR);
        }
 
+       ret_tkey = talloc_zero(mem_ctx, struct dns_res_rec);
+       if (ret_tkey == NULL) {
+               return WERR_NOMEM;
+       }
+
+       ret_tkey->name = talloc_strdup(ret_tkey, in_tkey->name);
+       if (ret_tkey->name == NULL) {
+               return WERR_NOMEM;
+       }
+
+       ret_tkey->rr_type = DNS_QTYPE_TKEY;
+       ret_tkey->rr_class = DNS_QCLASS_ANY;
+       ret_tkey->length = UINT16_MAX;
+
+       ret_tkey->rdata.tkey_record.algorithm = talloc_strdup(ret_tkey,
+                       in_tkey->rdata.tkey_record.algorithm);
+       if (ret_tkey->rdata.tkey_record.algorithm  == NULL) {
+               return WERR_NOMEM;
+       }
+
+       ret_tkey->rdata.tkey_record.inception = in_tkey->rdata.tkey_record.inception;
+       ret_tkey->rdata.tkey_record.expiration = in_tkey->rdata.tkey_record.expiration;
+       ret_tkey->rdata.tkey_record.mode = in_tkey->rdata.tkey_record.mode;
+
+       switch (in_tkey->rdata.tkey_record.mode) {
+       case DNS_TKEY_MODE_DH:
+               /* FIXME: According to RFC 2930, we MUST support this, but we don't.
+                * Still, claim it's a bad key instead of a bad mode */
+               ret_tkey->rdata.tkey_record.error = DNS_RCODE_BADKEY;
+               break;
+       case DNS_TKEY_MODE_GSSAPI: {
+               NTSTATUS status;
+               struct dns_server_tkey *tkey;
+               DATA_BLOB key;
+               DATA_BLOB reply;
+
+               tkey = dns_find_tkey(dns->tkeys, in->questions[0].name);
+               if (tkey != NULL && tkey->complete) {
+                       /* TODO: check if the key is still valid */
+                       DEBUG(1, ("Rejecting tkey negotiation for already established key\n"));
+                       ret_tkey->rdata.tkey_record.error = DNS_RCODE_BADNAME;
+                       break;
+               }
+
+               if (tkey == NULL) {
+                       status  = create_tkey(dns, in->questions[0].name,
+                                             in_tkey->rdata.tkey_record.algorithm,
+                                             &tkey);
+                       if (!NT_STATUS_IS_OK(status)) {
+                               ret_tkey->rdata.tkey_record.error = DNS_RCODE_BADKEY;
+                               return ntstatus_to_werror(status);
+                       }
+               }
+
+               key.data = in_tkey->rdata.tkey_record.key_data;
+               key.length = in_tkey->rdata.tkey_record.key_size;
+
+               status = accept_gss_ticket(ret_tkey, dns, tkey, &key, &reply,
+                                          &ret_tkey->rdata.tkey_record.error);
+               if (NT_STATUS_EQUAL(status, NT_STATUS_MORE_PROCESSING_REQUIRED)) {
+                       DEBUG(1, ("More processing required\n"));
+                       ret_tkey->rdata.tkey_record.error = DNS_RCODE_BADKEY;
+               } else if (NT_STATUS_IS_OK(status)) {
+                       DEBUG(1, ("Tkey handshake completed\n"));
+                       ret_tkey->rdata.tkey_record.key_size = reply.length;
+                       ret_tkey->rdata.tkey_record.key_data = talloc_memdup(ret_tkey,
+                                                               reply.data,
+                                                               reply.length);
+                       state->sign = true;
+                       state->key_name = talloc_strdup(mem_ctx, tkey->name);
+                       if (state->key_name == NULL) {
+                               return WERR_NOMEM;
+                       }
+               } else {
+                       DEBUG(1, ("GSS key negotiation returned %s\n", nt_errstr(status)));
+                       ret_tkey->rdata.tkey_record.error = DNS_RCODE_BADKEY;
+               }
+
+               break;
+               }
+       case DNS_TKEY_MODE_DELETE:
+               /* TODO: implement me */
+               DEBUG(1, ("Should delete tkey here\n"));
+               ret_tkey->rdata.tkey_record.error = DNS_RCODE_OK;
+               break;
+       case DNS_TKEY_MODE_NULL:
+       case DNS_TKEY_MODE_SERVER:
+       case DNS_TKEY_MODE_CLIENT:
+       case DNS_TKEY_MODE_LAST:
+               /* We don't have to implement these, return a mode error */
+               ret_tkey->rdata.tkey_record.error = DNS_RCODE_BADMODE;
+               break;
+       default:
+               DEBUG(1, ("Unsupported TKEY mode %d\n",
+                     in_tkey->rdata.tkey_record.mode));
+       }
+
+       *answers = ret_tkey;
+       *ancount = 1;
+
+       return WERR_OK;
+}
+
+struct dns_server_process_query_state {
+       struct dns_res_rec *answers;
+       uint16_t ancount;
+       struct dns_res_rec *nsrecs;
+       uint16_t nscount;
+       struct dns_res_rec *additional;
+       uint16_t arcount;
+};
+
+static void dns_server_process_query_got_response(struct tevent_req *subreq);
+
+struct tevent_req *dns_server_process_query_send(
+       TALLOC_CTX *mem_ctx, struct tevent_context *ev,
+       struct dns_server *dns, struct dns_request_state *req_state,
+       const struct dns_name_packet *in)
+{
+       struct tevent_req *req, *subreq;
+       struct dns_server_process_query_state *state;
+
+       req = tevent_req_create(mem_ctx, &state,
+                               struct dns_server_process_query_state);
+       if (req == NULL) {
+               return NULL;
+       }
+       if (in->qdcount != 1) {
+               tevent_req_werror(req, DNS_ERR(FORMAT_ERROR));
+               return tevent_req_post(req, ev);
+       }
+
        /* Windows returns NOT_IMPLEMENTED on this as well */
        if (in->questions[0].question_class == DNS_QCLASS_NONE) {
-               return DNS_ERR(NOT_IMPLEMENTED);
+               tevent_req_werror(req, DNS_ERR(NOT_IMPLEMENTED));
+               return tevent_req_post(req, ev);
+       }
+
+       if (in->questions[0].question_type == DNS_QTYPE_TKEY) {
+                WERROR err;
+
+               err = handle_tkey(dns, state, in, req_state,
+                                 &state->answers, &state->ancount);
+               if (tevent_req_werror(req, err)) {
+                       return tevent_req_post(req, ev);
+               }
+               tevent_req_done(req);
+               return tevent_req_post(req, ev);
        }
 
        if (dns_authorative_for_zone(dns, in->questions[0].name)) {
-               state->flags |= DNS_FLAG_AUTHORITATIVE;
-               werror = handle_question(dns, mem_ctx, &in->questions[0],
-                                        &ans, &num_answers);
-       } else {
-               if (state->flags & DNS_FLAG_RECURSION_DESIRED &&
-                   state->flags & DNS_FLAG_RECURSION_AVAIL) {
-                       DEBUG(2, ("Not authoritative for '%s', forwarding\n",
-                                 in->questions[0].name));
-                       werror = ask_forwarder(dns, mem_ctx, &in->questions[0],
-                                              &ans, &num_answers,
-                                              &ns, &num_nsrecs,
-                                              &adds, &num_additional);
-               } else {
-                       werror = DNS_ERR(NAME_ERROR);
+               WERROR err;
+
+               req_state->flags |= DNS_FLAG_AUTHORITATIVE;
+               err = handle_question(dns, state, &in->questions[0],
+                                     &state->answers, &state->ancount);
+               if (tevent_req_werror(req, err)) {
+                       return tevent_req_post(req, ev);
                }
+               tevent_req_done(req);
+               return tevent_req_post(req, ev);
        }
-       W_ERROR_NOT_OK_GOTO(werror, query_failed);
 
-       *answers = ans;
-       *ancount = num_answers;
+       if ((req_state->flags & DNS_FLAG_RECURSION_DESIRED) &&
+           (req_state->flags & DNS_FLAG_RECURSION_AVAIL)) {
+               DEBUG(2, ("Not authoritative for '%s', forwarding\n",
+                         in->questions[0].name));
 
-       /*FIXME: Do something for these */
-       *nsrecs  = ns;
-       *nscount = num_nsrecs;
+               subreq = ask_forwarder_send(
+                       state, ev, lpcfg_dns_forwarder(dns->task->lp_ctx),
+                       &in->questions[0]);
+               if (tevent_req_nomem(subreq, req)) {
+                       return tevent_req_post(req, ev);
+               }
+               tevent_req_set_callback(
+                       subreq, dns_server_process_query_got_response, req);
+               return req;
+       }
 
-       *additional = adds;
-       *arcount    = num_additional;
+       tevent_req_werror(req, DNS_ERR(NAME_ERROR));
+       return tevent_req_post(req, ev);
+}
 
-       return WERR_OK;
+static void dns_server_process_query_got_response(struct tevent_req *subreq)
+{
+       struct tevent_req *req = tevent_req_callback_data(
+               subreq, struct tevent_req);
+       struct dns_server_process_query_state *state = tevent_req_data(
+               req, struct dns_server_process_query_state);
+       WERROR err;
+
+       err = ask_forwarder_recv(subreq, state,
+                                &state->answers, &state->ancount,
+                                &state->nsrecs, &state->nscount,
+                                &state->additional, &state->arcount);
+       TALLOC_FREE(subreq);
+       if (tevent_req_werror(req, err)) {
+               return;
+       }
+       tevent_req_done(req);
+}
 
-query_failed:
-       /*FIXME: add our SOA record to nsrecs */
-       return werror;
+WERROR dns_server_process_query_recv(
+       struct tevent_req *req, TALLOC_CTX *mem_ctx,
+       struct dns_res_rec **answers,    uint16_t *ancount,
+       struct dns_res_rec **nsrecs,     uint16_t *nscount,
+       struct dns_res_rec **additional, uint16_t *arcount)
+{
+       struct dns_server_process_query_state *state = tevent_req_data(
+               req, struct dns_server_process_query_state);
+       WERROR err;
+
+       if (tevent_req_is_werror(req, &err)) {
+               return err;
+       }
+       *answers = talloc_move(mem_ctx, &state->answers);
+       *ancount = state->ancount;
+       *nsrecs = talloc_move(mem_ctx, &state->nsrecs);
+       *nscount = state->nscount;
+       *additional = talloc_move(mem_ctx, &state->additional);
+       *arcount = state->arcount;
+       return WERR_OK;
 }