#!/usr/bin/env python3 # # Copyright (C) 2018-2020 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 sys import exit from copy import deepcopy from vyos.config import Config from vyos import ConfigError from vyos.util import call from vyos.template import render config_file = r'/run/dhcp-relay/dhcpv6.conf' default_config_data = { 'listen_addr': [], 'upstream_addr': [], 'options': [], } def get_config(): relay = deepcopy(default_config_data) conf = Config() if not conf.exists('service dhcpv6-relay'): return None else: conf.set_level('service dhcpv6-relay') # Network interfaces/address to listen on for DHCPv6 query(s) if conf.exists('listen-interface'): interfaces = conf.list_nodes('listen-interface') for intf in interfaces: if conf.exists('listen-interface {0} address'.format(intf)): addr = conf.return_value('listen-interface {0} address'.format(intf)) listen = addr + '%' + intf relay['listen_addr'].append(listen) # Upstream interface/address for remote DHCPv6 server if conf.exists('upstream-interface'): interfaces = conf.list_nodes('upstream-interface') for intf in interfaces: addresses = conf.return_values('upstream-interface {0} address'.format(intf)) for addr in addresses: server = addr + '%' + intf relay['upstream_addr'].append(server) # Maximum hop count. When forwarding packets, dhcrelay discards packets # which have reached a hop count of COUNT. Default is 10. Maximum is 255. if conf.exists('max-hop-count'): count = '-c ' + conf.return_value('max-hop-count') relay['options'].append(count) if conf.exists('use-interface-id-option'): relay['options'].append('-I') return relay def verify(relay): # bail out early - looks like removal from running config if relay is None: return None if len(relay['listen_addr']) == 0 or len(relay['upstream_addr']) == 0: raise ConfigError('Must set at least one listen and upstream interface addresses.') return None def generate(relay): # bail out early - looks like removal from running config if relay is None: return None render(config_file, 'dhcpv6-relay/config.tmpl', relay) return None def apply(relay): if relay is not None: call('systemctl restart isc-dhcp-relay6.service') else: # DHCPv6 relay support is removed in the commit call('systemctl stop isc-dhcp-relay6.service') if os.path.exists(config_file): os.unlink(config_file) return None if __name__ == '__main__': try: c = get_config() verify(c) generate(c) apply(c) except ConfigError as e: print(e) exit(1)