[pd] add pd daemon service to support the automation of dhcpcd PD management

script/reference-device/dhcp6_pd_daemon.py

@@ -0,0 +1,96 @@
+#!/usr/bin/env python3
+#
+#  Copyright (c) 2024, The OpenThread Authors.
+#  All rights reserved.
+#
+#  Redistribution and use in source and binary forms, with or without
+#  modification, are permitted provided that the following conditions are met:
+#  1. Redistributions of source code must retain the above copyright
+#     notice, this list of conditions and the following disclaimer.
+#  2. Redistributions in binary form must reproduce the above copyright
+#     notice, this list of conditions and the following disclaimer in the
+#     documentation and/or other materials provided with the distribution.
+#  3. Neither the name of the copyright holder nor the
+#     names of its contributors may be used to endorse or promote products
+#     derived from this software without specific prior written permission.
+#
+#  THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS IS"
+#  AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
+#  IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
+#  ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT HOLDER OR CONTRIBUTORS BE
+#  LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR
+#  CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF
+#  SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS
+#  INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN
+#  CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE)
+#  ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
+#  POSSIBILITY OF SUCH DAMAGE.
+#
+
+import logging
+import dbus
+import gi.repository.GLib as GLib
+import subprocess
+import os
+
+from dbus.mainloop.glib import DBusGMainLoop
+DBusGMainLoop(set_as_default=True)
+
+logging.basicConfig(level=logging.INFO, format='%(asctime)s - %(levelname)s - %(message)s')
+
+bus = dbus.SystemBus()
+thread_dbus_obj = None
+iface = None
+backup_dir = "/var/lib/ot-dhcpcd-backup"
+
+def properties_changed_handler(interface_name, changed_properties, invalidated_properties):
+    if "Dhcp6PdState" in changed_properties:
+        new_state = changed_properties["Dhcp6PdState"]
+        logging.info(f"Dhcp6PdState changed to: {new_state}")
+        if new_state == "running":
+            os.makedirs(backup_dir, exist_ok=True)
+            subprocess.run(["sudo", "cp", "/etc/dhcpcd.conf", f"{backup_dir}/dhcpcd.conf.orig"], check=True)
+            try:
+                subprocess.run(["sudo", "systemctl", "daemon-reload"], check=True)
+                subprocess.run(["sudo", "service", "dhcpcd", "restart"], check=True)
+                logging.info("Successfully restarted dhcpcd service.")
+            except subprocess.CalledProcessError as e:
+                logging.error(f"Error restarting dhcpcd service: {e}")
+        elif new_state == "stopped":
+            if os.path.isfile(f"{backup_dir}/dhcpcd.conf.orig"):
+                try:
+                    subprocess.run(["sudo", "cp", f"{backup_dir}/dhcpcd.conf.orig", "/etc/dhcpcd.conf"], check=True)
+                    logging.info("Successfully restored default dhcpcd config.")
+                except subprocess.CalledProcessError as e:
+                    logging.error(f"Error restoring dhcpcd config: {e}")
+            else:
+                logging.error("Backup configuration file not found. Cannot restore default.")
+
+def connect_to_signal():
+    global thread_dbus_obj, thread_properties_dbus_iface
+    try:
+        thread_dbus_obj = bus.get_object('io.openthread.BorderRouter.wpan0', '/io/openthread/BorderRouter/wpan0')
+        thread_properties_dbus_iface = dbus.Interface(thread_dbus_obj, 'org.freedesktop.DBus.Properties')
+        thread_dbus_obj.connect_to_signal("PropertiesChanged", properties_changed_handler, dbus_interface=thread_properties_dbus_iface.dbus_interface)
+        logging.info("Connected to D-Bus signal.")
+    except dbus.DBusException as e:
+        logging.error(f"Error connecting to D-Bus: {e}")
+        thread_dbus_obj = None
+        thread_properties_dbus_iface = None
+
+def check_and_reconnect():
+    if thread_dbus_obj is None:
+        connect_to_signal()
+
+def main():
+    loop = GLib.MainLoop()
+
+    connect_to_signal()
+
+    GLib.timeout_add_seconds(5, check_and_reconnect)
+
+    loop.run()
+
+if __name__ == '__main__':
+    main()
+