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-rw-r--r--source4/dns_server/TODO15
-rw-r--r--source4/dns_server/dns_server.c522
-rw-r--r--source4/dns_server/dns_server.h33
-rw-r--r--source4/dns_server/wscript_build9
4 files changed, 579 insertions, 0 deletions
diff --git a/source4/dns_server/TODO b/source4/dns_server/TODO
new file mode 100644
index 0000000000..c6024d76ed
--- /dev/null
+++ b/source4/dns_server/TODO
@@ -0,0 +1,15 @@
+DNS server todo list
+--------------------
+
+Just so we don't forget the required features for an AD-compatible DNS server:
+
+- Forwarding to other nameservers if we don't know the domain
+- Additional record handling (especially in SOA records, but we'll want off of
+ this stuff)
+- TSIG-GSSAPI handling
+- Symmetric Bind-style key handling (not strictly needed for AD, but needed for
+ integration to other name servers / tools)
+- Command line tools that unix admins are used to
+- Zone transfer support (XFER, IFER)
+- Caching
+- Tests, tests, tests (probably based on python's dns implementation)
diff --git a/source4/dns_server/dns_server.c b/source4/dns_server/dns_server.c
new file mode 100644
index 0000000000..de9ad5336f
--- /dev/null
+++ b/source4/dns_server/dns_server.c
@@ -0,0 +1,522 @@
+/*
+ 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 "smbd/service_task.h"
+#include "smbd/service.h"
+#include "smbd/service_stream.h"
+#include "smbd/process_model.h"
+#include "lib/events/events.h"
+#include "lib/socket/socket.h"
+#include "lib/tsocket/tsocket.h"
+#include "libcli/util/tstream.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"
+
+/* 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");
+}
+
+bool dns_process(struct dns_server *dns,
+ TALLOC_CTX *mem_ctx,
+ DATA_BLOB *in,
+ DATA_BLOB *out)
+{
+ DEBUG(0, ("FIXME: actually process DNS packet here\n"));
+ return true;
+}
+
+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_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_tcp_call *call;
+ NTSTATUS status;
+ bool ok;
+
+ 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 krb5 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 +=4;
+ call->in.length -= 4;
+
+ /* Call dns */
+ ok = dns_process(dns_conn->dns_socket->dns, call, &call->in, &call->out);
+ if (!ok) {
+ dns_tcp_terminate_connection(dns_conn,
+ "dns_tcp_call_loop: process function failed");
+ return;
+ }
+
+ /* First add the length of the out buffer */
+ RSIVAL(call->out_hdr, 0, call->out.length);
+ call->out_iov[0].iov_base = (char *) call->out_hdr;
+ call->out_iov[0].iov_len = 4;
+
+ 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);
+
+ /*
+ * The krb5 tcp pdu's has the length as 4 byte (initial_read_size),
+ * packet_full_request_u32 provides the pdu length then.
+ */
+ subreq = tstream_read_pdu_blob_send(dns_conn,
+ dns_conn->conn->event.ctx,
+ dns_conn->tstream,
+ 4, /* initial_read_size */
+ packet_full_request_u32,
+ 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_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;
+ }
+
+ dns_conn->conn = conn;
+ dns_conn->dns_socket = dns_socket;
+ conn->private_data = dns_conn;
+
+ /*
+ * The krb5 tcp pdu's has the length as 4 byte (initial_read_size),
+ * packet_full_request_u32 provides the pdu length then.
+ */
+ subreq = tstream_read_pdu_blob_send(dns_conn,
+ dns_conn->conn->event.ctx,
+ dns_conn->tstream,
+ 4, /* initial_read_size */
+ packet_full_request_u32,
+ 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 tsocket_address *src;
+ DATA_BLOB in;
+ DATA_BLOB out;
+};
+
+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_udp_call *call;
+ uint8_t *buf;
+ ssize_t len;
+ int sys_errno;
+ bool ok;
+
+ call = talloc(sock, struct dns_udp_call);
+ if (call == NULL) {
+ talloc_free(call);
+ goto done;
+ }
+
+ 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 krb5 UDP packet of length %lu from %s\n",
+ (long)call->in.length,
+ tsocket_address_string(call->src, call)));
+
+ /* Call krb5 */
+ ok = dns_process(sock->dns_socket->dns, call, &call->in, &call->out);
+ if (!ok) {
+ talloc_free(call);
+ goto done;
+ }
+
+ subreq = tdgram_sendto_queue_send(call,
+ sock->dns_socket->dns->task->event_ctx,
+ sock->dgram,
+ sock->send_queue,
+ call->out.data,
+ call->out.length,
+ call->src);
+ if (subreq == NULL) {
+ talloc_free(call);
+ goto done;
+ }
+ tevent_req_set_callback(subreq, dns_udp_call_sendto_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_sendto_done(struct tevent_req *subreq)
+{
+ struct dns_udp_call *call = tevent_req_callback_data(subreq,
+ struct dns_udp_call);
+ ssize_t ret;
+ int sys_errno;
+
+ ret = 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(errno);
+ return status;
+ }
+
+ status = stream_setup_socket(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);
+ 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(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 loadparm_context *lp_ctx,
+ struct interface *ifaces)
+{
+ const struct model_ops *model_ops;
+ int num_interfaces;
+ TALLOC_CTX *tmp_ctx = talloc_new(dns);
+ NTSTATUS status;
+ int i;
+
+ /* within the dns task we want to be a single process, so
+ ask for the single process model ops and pass these to the
+ stream_setup_socket() call. */
+ model_ops = process_model_startup(dns->task->event_ctx, "single");
+ if (!model_ops) {
+ DEBUG(0,("Can't find 'single' process model_ops\n"));
+ return NT_STATUS_INTERNAL_ERROR;
+ }
+
+ num_interfaces = iface_count(ifaces);
+
+ for (i=0; i<num_interfaces; i++) {
+ const char *address = talloc_strdup(tmp_ctx, iface_n_ip(ifaces, i));
+
+ status = dns_add_socket(dns, model_ops, "dns", address, DNS_SERVICE_PORT);
+ NT_STATUS_NOT_OK_RETURN(status);
+ }
+
+ talloc_free(tmp_ctx);
+
+ return NT_STATUS_OK;
+}
+static void dns_task_init(struct task_server *task)
+{
+ struct dns_server *dns;
+ NTSTATUS status;
+ struct interface *ifaces;
+
+ switch (lpcfg_server_role(task->lp_ctx)) {
+ case ROLE_STANDALONE:
+ task_server_terminate(task, "dns: no DNS required in standalone configuration", false);
+ return;
+ case ROLE_DOMAIN_MEMBER:
+ task_server_terminate(task, "dns: no DNS required in member server configuration", false);
+ return;
+ case ROLE_DOMAIN_CONTROLLER:
+ /* Yes, we want a DNS */
+ break;
+ }
+
+ load_interfaces(task, lpcfg_interfaces(task->lp_ctx), &ifaces);
+
+ if (iface_count(ifaces) == 0) {
+ task_server_terminate(task, "dns: no network interfaces configured", false);
+ return;
+ }
+
+ task_server_set_title(task, "task[dns]");
+
+ dns = talloc(task, struct dns_server);
+ if (dns == NULL) {
+ task_server_terminate(task, "dns: out of memory", true);
+ return;
+ }
+
+ dns->task = task;
+
+ status = dns_startup_interfaces(dns, task->lp_ctx, ifaces);
+ if (!NT_STATUS_IS_OK(status)) {
+ task_server_terminate(task, "dns failed to setup interfaces", true);
+ return;
+ }
+}
+
+NTSTATUS server_service_dns_init(void)
+{
+ return register_server_service("dns", dns_task_init);
+}
diff --git a/source4/dns_server/dns_server.h b/source4/dns_server/dns_server.h
new file mode 100644
index 0000000000..ca12c5cd8e
--- /dev/null
+++ b/source4/dns_server/dns_server.h
@@ -0,0 +1,33 @@
+/*
+ Unix SMB/CIFS implementation.
+
+ DNS structures
+
+ 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/>.
+*/
+
+#ifndef __DNS_SERVER_H__
+#define __DNS_SERVER_H__
+
+#include "librpc/gen_ndr/dns.h"
+
+struct tsocket_address;
+
+struct dns_server {
+ struct task_server *task;
+};
+
+#endif /* __DNS_SERVER_H__ */
diff --git a/source4/dns_server/wscript_build b/source4/dns_server/wscript_build
new file mode 100644
index 0000000000..26ef7ddf1e
--- /dev/null
+++ b/source4/dns_server/wscript_build
@@ -0,0 +1,9 @@
+#!/usr/bin/env python
+
+bld.SAMBA_MODULE('DNS',
+ source='dns_server.c',
+ subsystem='service',
+ init_function='server_service_dns_init',
+ deps='LIBSAMBA-HOSTCONFIG LIBTSOCKET LIBSAMBA_TSOCKET',
+ local_include=False
+ )
generated by cgit (git 2.34.1) at 2024-11-20 15:11:47 +0000