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-rw-r--r--source4/dns_server/dns_server.c965
1 files changed, 965 insertions, 0 deletions
diff --git a/source4/dns_server/dns_server.c b/source4/dns_server/dns_server.c
new file mode 100644
index 0000000..0a36c1c
--- /dev/null
+++ b/source4/dns_server/dns_server.c
@@ -0,0 +1,965 @@
+/*
+ Unix SMB/CIFS implementation.
+
+ DNS server startup
+
+ Copyright (C) 2010 Kai Blin <kai@samba.org>
+
+ This program is free software; you can redistribute it and/or modify
+ it under the terms of the GNU General Public License as published by
+ the Free Software Foundation; either version 3 of the License, or
+ (at your option) any later version.
+
+ This program is distributed in the hope that it will be useful,
+ but WITHOUT ANY WARRANTY; without even the implied warranty of
+ MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
+ GNU General Public License for more details.
+
+ You should have received a copy of the GNU General Public License
+ along with this program. If not, see <http://www.gnu.org/licenses/>.
+*/
+
+#include "includes.h"
+#include "samba/service_task.h"
+#include "samba/service.h"
+#include "samba/service_stream.h"
+#include "samba/process_model.h"
+#include "lib/events/events.h"
+#include "lib/socket/socket.h"
+#include "lib/tsocket/tsocket.h"
+#include "libcli/util/tstream.h"
+#include "libcli/util/ntstatus.h"
+#include "system/network.h"
+#include "lib/stream/packet.h"
+#include "lib/socket/netif.h"
+#include "dns_server/dns_server.h"
+#include "param/param.h"
+#include "librpc/ndr/libndr.h"
+#include "librpc/gen_ndr/ndr_dns.h"
+#include "librpc/gen_ndr/ndr_dnsp.h"
+#include <ldb.h>
+#include "dsdb/samdb/samdb.h"
+#include "dsdb/common/util.h"
+#include "auth/session.h"
+#include "lib/util/dlinklist.h"
+#include "lib/util/tevent_werror.h"
+#include "auth/auth.h"
+#include "auth/credentials/credentials.h"
+#include "librpc/gen_ndr/ndr_irpc.h"
+#include "lib/messaging/irpc.h"
+#include "libds/common/roles.h"
+
+#undef DBGC_CLASS
+#define DBGC_CLASS DBGC_DNS
+
+NTSTATUS server_service_dns_init(TALLOC_CTX *);
+
+/* hold information about one dns socket */
+struct dns_socket {
+ struct dns_server *dns;
+ struct tsocket_address *local_address;
+};
+
+struct dns_udp_socket {
+ struct dns_socket *dns_socket;
+ struct tdgram_context *dgram;
+ struct tevent_queue *send_queue;
+};
+
+/*
+ state of an open tcp connection
+*/
+struct dns_tcp_connection {
+ /* stream connection we belong to */
+ struct stream_connection *conn;
+
+ /* the dns_server the connection belongs to */
+ struct dns_socket *dns_socket;
+
+ struct tstream_context *tstream;
+
+ struct tevent_queue *send_queue;
+};
+
+static void dns_tcp_terminate_connection(struct dns_tcp_connection *dnsconn, const char *reason)
+{
+ stream_terminate_connection(dnsconn->conn, reason);
+}
+
+static void dns_tcp_recv(struct stream_connection *conn, uint16_t flags)
+{
+ struct dns_tcp_connection *dnsconn = talloc_get_type(conn->private_data,
+ struct dns_tcp_connection);
+ /* this should never be triggered! */
+ dns_tcp_terminate_connection(dnsconn, "dns_tcp_recv: called");
+}
+
+static void dns_tcp_send(struct stream_connection *conn, uint16_t flags)
+{
+ struct dns_tcp_connection *dnsconn = talloc_get_type(conn->private_data,
+ struct dns_tcp_connection);
+ /* this should never be triggered! */
+ dns_tcp_terminate_connection(dnsconn, "dns_tcp_send: called");
+}
+
+struct dns_process_state {
+ DATA_BLOB *in;
+ struct dns_server *dns;
+ struct dns_name_packet in_packet;
+ struct dns_request_state state;
+ WERROR dns_err;
+ struct dns_name_packet out_packet;
+ DATA_BLOB out;
+};
+
+static void dns_process_done(struct tevent_req *subreq);
+
+static struct tevent_req *dns_process_send(TALLOC_CTX *mem_ctx,
+ struct tevent_context *ev,
+ struct dns_server *dns,
+ const struct tsocket_address *remote_address,
+ const struct tsocket_address *local_address,
+ DATA_BLOB *in)
+{
+ struct tevent_req *req, *subreq;
+ struct dns_process_state *state;
+ enum ndr_err_code ndr_err;
+ WERROR ret;
+ const char **forwarder = lpcfg_dns_forwarder(dns->task->lp_ctx);
+ req = tevent_req_create(mem_ctx, &state, struct dns_process_state);
+ if (req == NULL) {
+ return NULL;
+ }
+ state->state.mem_ctx = state;
+ state->in = in;
+
+ state->dns = dns;
+
+ if (in->length < 12) {
+ tevent_req_werror(req, WERR_INVALID_PARAMETER);
+ return tevent_req_post(req, ev);
+ }
+ dump_data_dbgc(DBGC_DNS, 8, in->data, in->length);
+
+ ndr_err = ndr_pull_struct_blob(
+ in, state, &state->in_packet,
+ (ndr_pull_flags_fn_t)ndr_pull_dns_name_packet);
+
+ if (!NDR_ERR_CODE_IS_SUCCESS(ndr_err)) {
+ DBG_NOTICE("ndr_pull_dns_name_packet() failed with %s\n",
+ ndr_map_error2string(ndr_err));
+ state->dns_err = DNS_ERR(FORMAT_ERROR);
+ tevent_req_done(req);
+ return tevent_req_post(req, ev);
+ }
+ if (DEBUGLVLC(DBGC_DNS, 8)) {
+ NDR_PRINT_DEBUGC(DBGC_DNS, dns_name_packet, &state->in_packet);
+ }
+
+ if (state->in_packet.operation & DNS_FLAG_REPLY) {
+ DBG_INFO("Won't reply to replies.\n");
+ tevent_req_werror(req, WERR_INVALID_PARAMETER);
+ return tevent_req_post(req, ev);
+ }
+
+ state->state.flags = state->in_packet.operation;
+ state->state.flags |= DNS_FLAG_REPLY;
+
+ state->state.local_address = local_address;
+ state->state.remote_address = remote_address;
+
+ if (forwarder && *forwarder && **forwarder) {
+ state->state.flags |= DNS_FLAG_RECURSION_AVAIL;
+ }
+
+ state->out_packet = state->in_packet;
+
+ ret = dns_verify_tsig(dns, state, &state->state,
+ &state->out_packet, in);
+ if (!W_ERROR_IS_OK(ret)) {
+ DBG_INFO("dns_verify_tsig() failed with %s\n",
+ win_errstr(ret));
+ state->dns_err = ret;
+ tevent_req_done(req);
+ return tevent_req_post(req, ev);
+ }
+
+ switch (state->in_packet.operation & DNS_OPCODE) {
+ case DNS_OPCODE_QUERY:
+ subreq = dns_server_process_query_send(
+ state, ev, dns,
+ &state->state, &state->in_packet);
+ if (tevent_req_nomem(subreq, req)) {
+ return tevent_req_post(req, ev);
+ }
+ tevent_req_set_callback(subreq, dns_process_done, req);
+ return req;
+ case DNS_OPCODE_UPDATE:
+ ret = dns_server_process_update(
+ dns, &state->state, state, &state->in_packet,
+ &state->out_packet.answers, &state->out_packet.ancount,
+ &state->out_packet.nsrecs, &state->out_packet.nscount,
+ &state->out_packet.additional,
+ &state->out_packet.arcount);
+ DBG_DEBUG("dns_server_process_update(): %s\n",
+ win_errstr(ret));
+ break;
+ default:
+ ret = WERR_DNS_ERROR_RCODE_NOT_IMPLEMENTED;
+ DBG_NOTICE("OPCODE[0x%x]: %s\n",
+ (state->in_packet.operation & DNS_OPCODE),
+ win_errstr(ret));
+ }
+ state->dns_err = ret;
+ tevent_req_done(req);
+ return tevent_req_post(req, ev);
+}
+
+static void dns_process_done(struct tevent_req *subreq)
+{
+ struct tevent_req *req = tevent_req_callback_data(
+ subreq, struct tevent_req);
+ struct dns_process_state *state = tevent_req_data(
+ req, struct dns_process_state);
+ WERROR ret;
+
+ ret = dns_server_process_query_recv(
+ subreq, state,
+ &state->out_packet.answers, &state->out_packet.ancount,
+ &state->out_packet.nsrecs, &state->out_packet.nscount,
+ &state->out_packet.additional, &state->out_packet.arcount);
+ TALLOC_FREE(subreq);
+
+ DBG_DEBUG("dns_server_process_query_recv(): %s\n",
+ win_errstr(ret));
+ state->dns_err = ret;
+ tevent_req_done(req);
+}
+
+static WERROR dns_process_recv(struct tevent_req *req, TALLOC_CTX *mem_ctx,
+ DATA_BLOB *out)
+{
+ struct dns_process_state *state = tevent_req_data(
+ req, struct dns_process_state);
+ enum ndr_err_code ndr_err;
+ uint16_t dns_err;
+ WERROR ret;
+
+ if (tevent_req_is_werror(req, &ret)) {
+ DBG_NOTICE("ERROR: %s from %s\n", win_errstr(ret),
+ tevent_req_print(state, req));
+ return ret;
+ }
+ dns_err = werr_to_dns_err(state->dns_err);
+ if ((dns_err != DNS_RCODE_OK) &&
+ (dns_err != DNS_RCODE_NXDOMAIN) &&
+ (dns_err != DNS_RCODE_NOTAUTH))
+ {
+ DBG_INFO("FAILURE: %s from %s\n",
+ win_errstr(state->dns_err),
+ tevent_req_print(state, req));
+ goto drop;
+ }
+ if (dns_err != DNS_RCODE_OK) {
+ DBG_DEBUG("INFO: %s from %s\n",
+ win_errstr(state->dns_err),
+ tevent_req_print(state, req));
+ state->out_packet.operation |= dns_err;
+ } else {
+ DBG_DEBUG("OK: %s\n",
+ tevent_req_print(state, req));
+ }
+ state->out_packet.operation |= state->state.flags;
+
+ if (state->state.sign) {
+ ret = dns_sign_tsig(state->dns, mem_ctx, &state->state,
+ &state->out_packet, 0);
+ if (!W_ERROR_IS_OK(ret)) {
+ DBG_WARNING("dns_sign_tsig() failed %s\n",
+ win_errstr(ret));
+ dns_err = DNS_RCODE_SERVFAIL;
+ goto drop;
+ }
+ }
+
+ if (DEBUGLVLC(DBGC_DNS, 8)) {
+ NDR_PRINT_DEBUGC(DBGC_DNS, dns_name_packet, &state->out_packet);
+ }
+
+ ndr_err = ndr_push_struct_blob(
+ out, mem_ctx, &state->out_packet,
+ (ndr_push_flags_fn_t)ndr_push_dns_name_packet);
+ if (!NDR_ERR_CODE_IS_SUCCESS(ndr_err)) {
+ DBG_WARNING("Failed to push packet: %s!\n",
+ ndr_errstr(ndr_err));
+ dns_err = DNS_RCODE_SERVFAIL;
+ goto drop;
+ }
+ return WERR_OK;
+
+drop:
+ *out = data_blob_talloc(mem_ctx, state->in->data, state->in->length);
+ if (out->data == NULL) {
+ return WERR_NOT_ENOUGH_MEMORY;
+ }
+ out->data[2] |= 0x80; /* Toggle DNS_FLAG_REPLY */
+ out->data[3] |= dns_err;
+ return WERR_OK;
+}
+
+struct dns_tcp_call {
+ struct dns_tcp_connection *dns_conn;
+ DATA_BLOB in;
+ DATA_BLOB out;
+ uint8_t out_hdr[4];
+ struct iovec out_iov[2];
+};
+
+static void dns_tcp_call_process_done(struct tevent_req *subreq);
+static void dns_tcp_call_writev_done(struct tevent_req *subreq);
+
+static void dns_tcp_call_loop(struct tevent_req *subreq)
+{
+ struct dns_tcp_connection *dns_conn = tevent_req_callback_data(subreq,
+ struct dns_tcp_connection);
+ struct dns_server *dns = dns_conn->dns_socket->dns;
+ struct dns_tcp_call *call;
+ NTSTATUS status;
+
+ call = talloc(dns_conn, struct dns_tcp_call);
+ if (call == NULL) {
+ dns_tcp_terminate_connection(dns_conn, "dns_tcp_call_loop: "
+ "no memory for dns_tcp_call");
+ return;
+ }
+ call->dns_conn = dns_conn;
+
+ status = tstream_read_pdu_blob_recv(subreq,
+ call,
+ &call->in);
+ TALLOC_FREE(subreq);
+ if (!NT_STATUS_IS_OK(status)) {
+ const char *reason;
+
+ reason = talloc_asprintf(call, "dns_tcp_call_loop: "
+ "tstream_read_pdu_blob_recv() - %s",
+ nt_errstr(status));
+ if (!reason) {
+ reason = nt_errstr(status);
+ }
+
+ dns_tcp_terminate_connection(dns_conn, reason);
+ return;
+ }
+
+ DEBUG(10,("Received DNS TCP packet of length %lu from %s\n",
+ (long) call->in.length,
+ tsocket_address_string(dns_conn->conn->remote_address, call)));
+
+ /* skip length header */
+ call->in.data += 2;
+ call->in.length -= 2;
+
+ subreq = dns_process_send(call, dns->task->event_ctx, dns,
+ dns_conn->conn->remote_address,
+ dns_conn->conn->local_address,
+ &call->in);
+ if (subreq == NULL) {
+ dns_tcp_terminate_connection(
+ dns_conn, "dns_tcp_call_loop: dns_process_send "
+ "failed\n");
+ return;
+ }
+ tevent_req_set_callback(subreq, dns_tcp_call_process_done, call);
+
+ /*
+ * The dns tcp pdu's has the length as 2 byte (initial_read_size),
+ * tstream_full_request_u16 provides the pdu length then.
+ */
+ subreq = tstream_read_pdu_blob_send(dns_conn,
+ dns_conn->conn->event.ctx,
+ dns_conn->tstream,
+ 2, /* initial_read_size */
+ tstream_full_request_u16,
+ dns_conn);
+ if (subreq == NULL) {
+ dns_tcp_terminate_connection(dns_conn, "dns_tcp_call_loop: "
+ "no memory for tstream_read_pdu_blob_send");
+ return;
+ }
+ tevent_req_set_callback(subreq, dns_tcp_call_loop, dns_conn);
+}
+
+static void dns_tcp_call_process_done(struct tevent_req *subreq)
+{
+ struct dns_tcp_call *call = tevent_req_callback_data(subreq,
+ struct dns_tcp_call);
+ struct dns_tcp_connection *dns_conn = call->dns_conn;
+ WERROR err;
+
+ err = dns_process_recv(subreq, call, &call->out);
+ TALLOC_FREE(subreq);
+ if (!W_ERROR_IS_OK(err)) {
+ DEBUG(1, ("dns_process returned %s\n", win_errstr(err)));
+ dns_tcp_terminate_connection(dns_conn,
+ "dns_tcp_call_loop: process function failed");
+ return;
+ }
+
+ /* First add the length of the out buffer */
+ RSSVAL(call->out_hdr, 0, call->out.length);
+ call->out_iov[0].iov_base = (char *) call->out_hdr;
+ call->out_iov[0].iov_len = 2;
+
+ call->out_iov[1].iov_base = (char *) call->out.data;
+ call->out_iov[1].iov_len = call->out.length;
+
+ subreq = tstream_writev_queue_send(call,
+ dns_conn->conn->event.ctx,
+ dns_conn->tstream,
+ dns_conn->send_queue,
+ call->out_iov, 2);
+ if (subreq == NULL) {
+ dns_tcp_terminate_connection(dns_conn, "dns_tcp_call_loop: "
+ "no memory for tstream_writev_queue_send");
+ return;
+ }
+ tevent_req_set_callback(subreq, dns_tcp_call_writev_done, call);
+}
+
+static void dns_tcp_call_writev_done(struct tevent_req *subreq)
+{
+ struct dns_tcp_call *call = tevent_req_callback_data(subreq,
+ struct dns_tcp_call);
+ int sys_errno;
+ int rc;
+
+ rc = tstream_writev_queue_recv(subreq, &sys_errno);
+ TALLOC_FREE(subreq);
+ if (rc == -1) {
+ const char *reason;
+
+ reason = talloc_asprintf(call, "dns_tcp_call_writev_done: "
+ "tstream_writev_queue_recv() - %d:%s",
+ sys_errno, strerror(sys_errno));
+ if (!reason) {
+ reason = "dns_tcp_call_writev_done: tstream_writev_queue_recv() failed";
+ }
+
+ dns_tcp_terminate_connection(call->dns_conn, reason);
+ return;
+ }
+
+ /* We don't care about errors */
+
+ talloc_free(call);
+}
+
+/*
+ called when we get a new connection
+*/
+static void dns_tcp_accept(struct stream_connection *conn)
+{
+ struct dns_socket *dns_socket;
+ struct dns_tcp_connection *dns_conn;
+ struct tevent_req *subreq;
+ int rc;
+
+ dns_conn = talloc_zero(conn, struct dns_tcp_connection);
+ if (dns_conn == NULL) {
+ stream_terminate_connection(conn,
+ "dns_tcp_accept: out of memory");
+ return;
+ }
+
+ dns_conn->send_queue = tevent_queue_create(conn, "dns_tcp_accept");
+ if (dns_conn->send_queue == NULL) {
+ stream_terminate_connection(conn,
+ "dns_tcp_accept: out of memory");
+ return;
+ }
+
+ dns_socket = talloc_get_type(conn->private_data, struct dns_socket);
+
+ TALLOC_FREE(conn->event.fde);
+
+ rc = tstream_bsd_existing_socket(dns_conn,
+ socket_get_fd(conn->socket),
+ &dns_conn->tstream);
+ if (rc < 0) {
+ stream_terminate_connection(conn,
+ "dns_tcp_accept: out of memory");
+ return;
+ }
+ /* as server we want to fail early */
+ tstream_bsd_fail_readv_first_error(dns_conn->tstream, true);
+
+ dns_conn->conn = conn;
+ dns_conn->dns_socket = dns_socket;
+ conn->private_data = dns_conn;
+
+ /*
+ * The dns tcp pdu's has the length as 2 byte (initial_read_size),
+ * tstream_full_request_u16 provides the pdu length then.
+ */
+ subreq = tstream_read_pdu_blob_send(dns_conn,
+ dns_conn->conn->event.ctx,
+ dns_conn->tstream,
+ 2, /* initial_read_size */
+ tstream_full_request_u16,
+ dns_conn);
+ if (subreq == NULL) {
+ dns_tcp_terminate_connection(dns_conn, "dns_tcp_accept: "
+ "no memory for tstream_read_pdu_blob_send");
+ return;
+ }
+ tevent_req_set_callback(subreq, dns_tcp_call_loop, dns_conn);
+}
+
+static const struct stream_server_ops dns_tcp_stream_ops = {
+ .name = "dns_tcp",
+ .accept_connection = dns_tcp_accept,
+ .recv_handler = dns_tcp_recv,
+ .send_handler = dns_tcp_send
+};
+
+struct dns_udp_call {
+ struct dns_udp_socket *sock;
+ struct tsocket_address *src;
+ DATA_BLOB in;
+ DATA_BLOB out;
+};
+
+static void dns_udp_call_process_done(struct tevent_req *subreq);
+static void dns_udp_call_sendto_done(struct tevent_req *subreq);
+
+static void dns_udp_call_loop(struct tevent_req *subreq)
+{
+ struct dns_udp_socket *sock = tevent_req_callback_data(subreq,
+ struct dns_udp_socket);
+ struct dns_server *dns = sock->dns_socket->dns;
+ struct dns_udp_call *call;
+ uint8_t *buf;
+ ssize_t len;
+ int sys_errno;
+
+ call = talloc(sock, struct dns_udp_call);
+ if (call == NULL) {
+ talloc_free(call);
+ goto done;
+ }
+ call->sock = sock;
+
+ len = tdgram_recvfrom_recv(subreq, &sys_errno,
+ call, &buf, &call->src);
+ TALLOC_FREE(subreq);
+ if (len == -1) {
+ talloc_free(call);
+ goto done;
+ }
+
+ call->in.data = buf;
+ call->in.length = len;
+
+ DEBUG(10,("Received DNS UDP packet of length %lu from %s\n",
+ (long)call->in.length,
+ tsocket_address_string(call->src, call)));
+
+ subreq = dns_process_send(call, dns->task->event_ctx, dns,
+ call->src,
+ sock->dns_socket->local_address,
+ &call->in);
+ if (subreq == NULL) {
+ TALLOC_FREE(call);
+ goto done;
+ }
+ tevent_req_set_callback(subreq, dns_udp_call_process_done, call);
+
+done:
+ subreq = tdgram_recvfrom_send(sock,
+ sock->dns_socket->dns->task->event_ctx,
+ sock->dgram);
+ if (subreq == NULL) {
+ task_server_terminate(sock->dns_socket->dns->task,
+ "no memory for tdgram_recvfrom_send",
+ true);
+ return;
+ }
+ tevent_req_set_callback(subreq, dns_udp_call_loop, sock);
+}
+
+static void dns_udp_call_process_done(struct tevent_req *subreq)
+{
+ struct dns_udp_call *call = tevent_req_callback_data(
+ subreq, struct dns_udp_call);
+ struct dns_udp_socket *sock = call->sock;
+ struct dns_server *dns = sock->dns_socket->dns;
+ WERROR err;
+
+ err = dns_process_recv(subreq, call, &call->out);
+ TALLOC_FREE(subreq);
+ if (!W_ERROR_IS_OK(err)) {
+ DEBUG(1, ("dns_process returned %s\n", win_errstr(err)));
+ TALLOC_FREE(call);
+ return;
+ }
+
+ subreq = tdgram_sendto_queue_send(call,
+ dns->task->event_ctx,
+ sock->dgram,
+ sock->send_queue,
+ call->out.data,
+ call->out.length,
+ call->src);
+ if (subreq == NULL) {
+ talloc_free(call);
+ return;
+ }
+ tevent_req_set_callback(subreq, dns_udp_call_sendto_done, call);
+
+}
+static void dns_udp_call_sendto_done(struct tevent_req *subreq)
+{
+ struct dns_udp_call *call = tevent_req_callback_data(subreq,
+ struct dns_udp_call);
+ int sys_errno;
+
+ tdgram_sendto_queue_recv(subreq, &sys_errno);
+
+ /* We don't care about errors */
+
+ talloc_free(call);
+}
+
+/*
+ start listening on the given address
+*/
+static NTSTATUS dns_add_socket(struct dns_server *dns,
+ const struct model_ops *model_ops,
+ const char *name,
+ const char *address,
+ uint16_t port)
+{
+ struct dns_socket *dns_socket;
+ struct dns_udp_socket *dns_udp_socket;
+ struct tevent_req *udpsubreq;
+ NTSTATUS status;
+ int ret;
+
+ dns_socket = talloc(dns, struct dns_socket);
+ NT_STATUS_HAVE_NO_MEMORY(dns_socket);
+
+ dns_socket->dns = dns;
+
+ ret = tsocket_address_inet_from_strings(dns_socket, "ip",
+ address, port,
+ &dns_socket->local_address);
+ if (ret != 0) {
+ status = map_nt_error_from_unix_common(errno);
+ return status;
+ }
+
+ status = stream_setup_socket(dns->task,
+ dns->task->event_ctx,
+ dns->task->lp_ctx,
+ model_ops,
+ &dns_tcp_stream_ops,
+ "ip", address, &port,
+ lpcfg_socket_options(dns->task->lp_ctx),
+ dns_socket,
+ dns->task->process_context);
+ if (!NT_STATUS_IS_OK(status)) {
+ DEBUG(0,("Failed to bind to %s:%u TCP - %s\n",
+ address, port, nt_errstr(status)));
+ talloc_free(dns_socket);
+ return status;
+ }
+
+ dns_udp_socket = talloc(dns_socket, struct dns_udp_socket);
+ NT_STATUS_HAVE_NO_MEMORY(dns_udp_socket);
+
+ dns_udp_socket->dns_socket = dns_socket;
+
+ ret = tdgram_inet_udp_socket(dns_socket->local_address,
+ NULL,
+ dns_udp_socket,
+ &dns_udp_socket->dgram);
+ if (ret != 0) {
+ status = map_nt_error_from_unix_common(errno);
+ DEBUG(0,("Failed to bind to %s:%u UDP - %s\n",
+ address, port, nt_errstr(status)));
+ return status;
+ }
+
+ dns_udp_socket->send_queue = tevent_queue_create(dns_udp_socket,
+ "dns_udp_send_queue");
+ NT_STATUS_HAVE_NO_MEMORY(dns_udp_socket->send_queue);
+
+ udpsubreq = tdgram_recvfrom_send(dns_udp_socket,
+ dns->task->event_ctx,
+ dns_udp_socket->dgram);
+ NT_STATUS_HAVE_NO_MEMORY(udpsubreq);
+ tevent_req_set_callback(udpsubreq, dns_udp_call_loop, dns_udp_socket);
+
+ return NT_STATUS_OK;
+}
+
+/*
+ setup our listening sockets on the configured network interfaces
+*/
+static NTSTATUS dns_startup_interfaces(struct dns_server *dns,
+ struct interface *ifaces,
+ const struct model_ops *model_ops)
+{
+ size_t num_interfaces;
+ TALLOC_CTX *tmp_ctx = talloc_new(dns);
+ NTSTATUS status;
+ int i;
+
+ if (ifaces != NULL) {
+ num_interfaces = iface_list_count(ifaces);
+
+ for (i=0; i<num_interfaces; i++) {
+ const char *address = talloc_strdup(tmp_ctx,
+ iface_list_n_ip(ifaces, i));
+
+ status = dns_add_socket(dns, model_ops, "dns", address,
+ lpcfg_dns_port(dns->task->lp_ctx));
+ NT_STATUS_NOT_OK_RETURN(status);
+ }
+ } else {
+ size_t num_binds = 0;
+ char **wcard;
+ wcard = iface_list_wildcard(tmp_ctx);
+ if (wcard == NULL) {
+ DEBUG(0, ("No wildcard address available\n"));
+ return NT_STATUS_INTERNAL_ERROR;
+ }
+ for (i = 0; wcard[i] != NULL; i++) {
+ status = dns_add_socket(dns, model_ops, "dns", wcard[i],
+ lpcfg_dns_port(dns->task->lp_ctx));
+ if (NT_STATUS_IS_OK(status)) {
+ num_binds++;
+ }
+ }
+ if (num_binds == 0) {
+ talloc_free(tmp_ctx);
+ return NT_STATUS_INVALID_PARAMETER_MIX;
+ }
+ }
+
+ talloc_free(tmp_ctx);
+
+ return NT_STATUS_OK;
+}
+
+static struct dns_server_tkey_store *tkey_store_init(TALLOC_CTX *mem_ctx,
+ uint16_t size)
+{
+ struct dns_server_tkey_store *buffer = talloc_zero(mem_ctx,
+ struct dns_server_tkey_store);
+
+ if (buffer == NULL) {
+ return NULL;
+ }
+
+ buffer->size = size;
+ buffer->next_idx = 0;
+
+ buffer->tkeys = talloc_zero_array(buffer, struct dns_server_tkey *, size);
+ if (buffer->tkeys == NULL) {
+ TALLOC_FREE(buffer);
+ }
+
+ return buffer;
+}
+
+static NTSTATUS dns_server_reload_zones(struct dns_server *dns)
+{
+ NTSTATUS status;
+ struct dns_server_zone *new_list = NULL;
+ struct dns_server_zone *old_list = dns->zones;
+ struct dns_server_zone *old_zone;
+ status = dns_common_zones(dns->samdb, dns, NULL, &new_list);
+ if (!NT_STATUS_IS_OK(status)) {
+ return status;
+ }
+ dns->zones = new_list;
+ while ((old_zone = DLIST_TAIL(old_list)) != NULL) {
+ DLIST_REMOVE(old_list, old_zone);
+ talloc_free(old_zone);
+ }
+
+ return NT_STATUS_OK;
+}
+
+/**
+ * Called when the internal DNS server should reload the zones from DB, for
+ * example, when zones are added or deleted through RPC or replicated by
+ * inbound DRS.
+ */
+static NTSTATUS dns_reload_zones(struct irpc_message *msg,
+ struct dnssrv_reload_dns_zones *r)
+{
+ struct dns_server *dns;
+
+ dns = talloc_get_type(msg->private_data, struct dns_server);
+ if (dns == NULL) {
+ r->out.result = NT_STATUS_INTERNAL_ERROR;
+ return NT_STATUS_INTERNAL_ERROR;
+ }
+
+ r->out.result = dns_server_reload_zones(dns);
+
+ return NT_STATUS_OK;
+}
+
+static NTSTATUS dns_task_init(struct task_server *task)
+{
+ struct dns_server *dns;
+ NTSTATUS status;
+ struct interface *ifaces = NULL;
+ int ret;
+ static const char * const attrs_none[] = { NULL};
+ struct ldb_message *dns_acc;
+ char *hostname_lower;
+ char *dns_spn;
+ bool ok;
+
+ switch (lpcfg_server_role(task->lp_ctx)) {
+ case ROLE_STANDALONE:
+ task_server_terminate(task, "dns: no DNS required in standalone configuration", false);
+ return NT_STATUS_INVALID_DOMAIN_ROLE;
+ case ROLE_DOMAIN_MEMBER:
+ task_server_terminate(task, "dns: no DNS required in member server configuration", false);
+ return NT_STATUS_INVALID_DOMAIN_ROLE;
+ case ROLE_ACTIVE_DIRECTORY_DC:
+ /* Yes, we want a DNS */
+ break;
+ }
+
+ if (lpcfg_interfaces(task->lp_ctx) && lpcfg_bind_interfaces_only(task->lp_ctx)) {
+ load_interface_list(task, task->lp_ctx, &ifaces);
+
+ if (iface_list_count(ifaces) == 0) {
+ task_server_terminate(task, "dns: no network interfaces configured", false);
+ return NT_STATUS_UNSUCCESSFUL;
+ }
+ }
+
+ task_server_set_title(task, "task[dns]");
+
+ dns = talloc_zero(task, struct dns_server);
+ if (dns == NULL) {
+ task_server_terminate(task, "dns: out of memory", true);
+ return NT_STATUS_NO_MEMORY;
+ }
+
+ dns->task = task;
+
+ dns->server_credentials = cli_credentials_init(dns);
+ if (!dns->server_credentials) {
+ task_server_terminate(task, "Failed to init server credentials\n", true);
+ return NT_STATUS_UNSUCCESSFUL;
+ }
+
+ dns->samdb = samdb_connect(dns,
+ dns->task->event_ctx,
+ dns->task->lp_ctx,
+ system_session(dns->task->lp_ctx),
+ NULL,
+ 0);
+ if (!dns->samdb) {
+ task_server_terminate(task, "dns: samdb_connect failed", true);
+ return NT_STATUS_UNSUCCESSFUL;
+ }
+
+ ok = cli_credentials_set_conf(dns->server_credentials, task->lp_ctx);
+ if (!ok) {
+ task_server_terminate(task,
+ "dns: failed to load smb.conf",
+ true);
+ return NT_STATUS_UNSUCCESSFUL;
+ }
+
+ hostname_lower = strlower_talloc(dns, lpcfg_netbios_name(task->lp_ctx));
+ dns_spn = talloc_asprintf(dns, "DNS/%s.%s",
+ hostname_lower,
+ lpcfg_dnsdomain(task->lp_ctx));
+ TALLOC_FREE(hostname_lower);
+
+ ret = dsdb_search_one(dns->samdb, dns, &dns_acc,
+ ldb_get_default_basedn(dns->samdb), LDB_SCOPE_SUBTREE,
+ attrs_none, 0, "(servicePrincipalName=%s)",
+ dns_spn);
+ if (ret == LDB_SUCCESS) {
+ TALLOC_FREE(dns_acc);
+ if (!dns_spn) {
+ task_server_terminate(task, "dns: talloc_asprintf failed", true);
+ return NT_STATUS_UNSUCCESSFUL;
+ }
+ status = cli_credentials_set_stored_principal(dns->server_credentials, task->lp_ctx, dns_spn);
+ if (!NT_STATUS_IS_OK(status)) {
+ task_server_terminate(task,
+ talloc_asprintf(task, "Failed to obtain server credentials for DNS, "
+ "despite finding it in the samdb! %s\n",
+ nt_errstr(status)),
+ true);
+ return status;
+ }
+ } else {
+ TALLOC_FREE(dns_spn);
+ status = cli_credentials_set_machine_account(dns->server_credentials, task->lp_ctx);
+ if (!NT_STATUS_IS_OK(status)) {
+ task_server_terminate(task,
+ talloc_asprintf(task, "Failed to obtain server credentials, perhaps a standalone server?: %s\n",
+ nt_errstr(status)),
+ true);
+ return status;
+ }
+ }
+
+ dns->tkeys = tkey_store_init(dns, TKEY_BUFFER_SIZE);
+ if (!dns->tkeys) {
+ task_server_terminate(task, "Failed to allocate tkey storage\n", true);
+ return NT_STATUS_NO_MEMORY;
+ }
+
+ status = dns_server_reload_zones(dns);
+ if (!NT_STATUS_IS_OK(status)) {
+ task_server_terminate(task, "dns: failed to load DNS zones", true);
+ return status;
+ }
+
+ status = dns_startup_interfaces(dns, ifaces, task->model_ops);
+ if (!NT_STATUS_IS_OK(status)) {
+ task_server_terminate(task, "dns failed to setup interfaces", true);
+ return status;
+ }
+
+ /* Setup the IRPC interface and register handlers */
+ status = irpc_add_name(task->msg_ctx, "dnssrv");
+ if (!NT_STATUS_IS_OK(status)) {
+ task_server_terminate(task, "dns: failed to register IRPC name", true);
+ return status;
+ }
+
+ status = IRPC_REGISTER(task->msg_ctx, irpc, DNSSRV_RELOAD_DNS_ZONES,
+ dns_reload_zones, dns);
+ if (!NT_STATUS_IS_OK(status)) {
+ task_server_terminate(task, "dns: failed to setup reload handler", true);
+ return status;
+ }
+ return NT_STATUS_OK;
+}
+
+NTSTATUS server_service_dns_init(TALLOC_CTX *ctx)
+{
+ static const struct service_details details = {
+ .inhibit_fork_on_accept = true,
+ .inhibit_pre_fork = true,
+ .task_init = dns_task_init,
+ .post_fork = NULL
+ };
+ return register_server_service(ctx, "dns", &details);
+}
generated by cgit v1.2.3 (git 2.39.1) at 2024-06-07 02:41:57 +0000