#!/usr/bin/env python3 # # Copyright (C) 2017-2022 VyOS maintainers and contributors # # This program is free software; you can redistribute it and/or modify # it under the terms of the GNU General Public License version 2 or later as # published by the Free Software Foundation. # # 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/>. import os from json import loads from sys import exit from netifaces import ifaddresses, interfaces, AF_INET from vyos.config import Config from vyos.ifconfig.vrrp import VRRP from vyos.template import render from vyos.util import call from vyos import ConfigError from vyos import airbag airbag.enable() config_file = '/run/avahi-daemon/avahi-daemon.conf' vrrp_running_file = '/run/mdns_vrrp_active' def get_config(config=None): if config: conf = config else: conf = Config() base = ['service', 'mdns', 'repeater'] mdns = conf.get_config_dict(base, key_mangling=('-', '_'), get_first_key=True) if mdns: mdns['vrrp_exists'] = conf.exists('high-availability vrrp') return mdns def verify(mdns): if not mdns: return None if 'disable' in mdns: return None # We need at least two interfaces to repeat mDNS advertisments if 'interface' not in mdns or len(mdns['interface']) < 2: raise ConfigError('mDNS repeater requires at least 2 configured interfaces!') # For mdns-repeater to work it is essential that the interfaces has # an IPv4 address assigned for interface in mdns['interface']: if interface not in interfaces(): raise ConfigError(f'Interface "{interface}" does not exist!') if AF_INET not in ifaddresses(interface): raise ConfigError('mDNS repeater requires an IPv4 address to be ' f'configured on interface "{interface}"') return None # Get VRRP states from interfaces, returns only interfaces where state is MASTER def get_vrrp_master(interfaces): json_data = loads(VRRP.collect('json')) for group in json_data: if 'data' in group: if 'ifp_ifname' in group['data']: iface = group['data']['ifp_ifname'] state = group['data']['state'] # 2 = Master if iface in interfaces and state != 2: interfaces.remove(iface) return interfaces def generate(mdns): if not mdns: return None if 'disable' in mdns: print('Warning: mDNS repeater will be deactivated because it is disabled') return None if mdns['vrrp_exists'] and 'vrrp_disable' in mdns: mdns['interface'] = get_vrrp_master(mdns['interface']) if len(mdns['interface']) < 2: return None render(config_file, 'mdns-repeater/avahi-daemon.j2', mdns) return None def apply(mdns): if not mdns or 'disable' in mdns: call('systemctl stop avahi-daemon.service') if os.path.exists(config_file): os.unlink(config_file) if os.path.exists(vrrp_running_file): os.unlink(vrrp_running_file) else: if 'vrrp_disable' not in mdns and os.path.exists(vrrp_running_file): os.unlink(vrrp_running_file) if mdns['vrrp_exists'] and 'vrrp_disable' in mdns: if not os.path.exists(vrrp_running_file): os.mknod(vrrp_running_file) # vrrp script looks for this file to update mdns repeater if len(mdns['interface']) < 2: call('systemctl stop avahi-daemon.service') return None call('systemctl restart avahi-daemon.service') return None if __name__ == '__main__': try: c = get_config() verify(c) generate(c) apply(c) except ConfigError as e: print(e) exit(1)