#!/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 vyos.config import Config from vyos.configdict import dict_merge from vyos.ifconfig import Interface from vyos.template import render from vyos.util import call from vyos.util import dict_search from vyos.validate import is_ipv6_link_local from vyos.xml import defaults from vyos import ConfigError from vyos import airbag airbag.enable() config_file = '/run/dhcp-relay/dhcrelay6.conf' def get_config(config=None): if config: conf = config else: conf = Config() base = ['service', 'dhcpv6-relay'] if not conf.exists(base): return None relay = conf.get_config_dict(base, key_mangling=('-', '_'), get_first_key=True) # We have gathered the dict representation of the CLI, but there are default # options which we need to update into the dictionary retrived. default_values = defaults(base) relay = dict_merge(default_values, relay) return relay def verify(relay): # bail out early - looks like removal from running config if not relay: return None if 'upstream_interface' not in relay: raise ConfigError('At least one upstream interface required!') for interface, config in relay['upstream_interface'].items(): if 'address' not in config: raise ConfigError('DHCPv6 server required for upstream ' \ f'interface {interface}!') if 'listen_interface' not in relay: raise ConfigError('At least one listen interface required!') # DHCPv6 relay requires at least one global unicat address assigned to the # interface for interface in relay['listen_interface']: has_global = False for addr in Interface(interface).get_addr(): if not is_ipv6_link_local(addr): has_global = True if not has_global: raise ConfigError(f'Interface {interface} does not have global '\ 'IPv6 address assigned!') return None def generate(relay): # bail out early - looks like removal from running config if not relay: return None render(config_file, 'dhcp-relay/dhcrelay6.conf.j2', relay) return None def apply(relay): # bail out early - looks like removal from running config service_name = 'isc-dhcp-relay6.service' if not relay: # DHCPv6 relay support is removed in the commit call(f'systemctl stop {service_name}') if os.path.exists(config_file): os.unlink(config_file) return None call(f'systemctl restart {service_name}') return None if __name__ == '__main__': try: c = get_config() verify(c) generate(c) apply(c) except ConfigError as e: print(e) exit(1)