#!/usr/bin/env python3 # # Copyright (C) 2020-2021 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 jmespath import json import os from sys import exit from netifaces import interfaces from vyos.base import Warning from vyos.config import Config from vyos.configdep import set_dependents, call_dependents from vyos.template import render from vyos.utils.process import cmd from vyos.utils.kernel import check_kmod from vyos.utils.dict import dict_search from vyos.template import is_ipv6 from vyos import ConfigError from vyos import airbag airbag.enable() k_mod = ['nft_nat', 'nft_chain_nat'] nftables_nat66_config = '/run/nftables_nat66.nft' ndppd_config = '/run/ndppd/ndppd.conf' def get_config(config=None): if config: conf = config else: conf = Config() base = ['nat66'] nat = conf.get_config_dict(base, key_mangling=('-', '_'), get_first_key=True) set_dependents('conntrack', conf) if not conf.exists(base): nat['deleted'] = '' return nat def verify(nat): if not nat or 'deleted' in nat: # no need to verify the CLI as NAT66 is going to be deactivated return None if dict_search('source.rule', nat): for rule, config in dict_search('source.rule', nat).items(): err_msg = f'Source NAT66 configuration error in rule {rule}:' if 'outbound_interface' not in config: raise ConfigError(f'{err_msg} outbound-interface not specified') if config['outbound_interface'] not in interfaces(): raise ConfigError(f'rule "{rule}" interface "{config["outbound_interface"]}" does not exist on this system') addr = dict_search('translation.address', config) if addr != None: if addr != 'masquerade' and not is_ipv6(addr): raise ConfigError(f'IPv6 address {addr} is not a valid address') else: if 'exclude' not in config: raise ConfigError(f'{err_msg} translation address not specified') prefix = dict_search('source.prefix', config) if prefix != None: if not is_ipv6(prefix): raise ConfigError(f'{err_msg} source-prefix not specified') if dict_search('destination.rule', nat): for rule, config in dict_search('destination.rule', nat).items(): err_msg = f'Destination NAT66 configuration error in rule {rule}:' if 'inbound_interface' not in config: raise ConfigError(f'{err_msg}\n' \ 'inbound-interface not specified') else: if config['inbound_interface'] not in 'any' and config['inbound_interface'] not in interfaces(): Warning(f'rule "{rule}" interface "{config["inbound_interface"]}" does not exist on this system') return None def generate(nat): if not os.path.exists(nftables_nat66_config): nat['first_install'] = True render(nftables_nat66_config, 'firewall/nftables-nat66.j2', nat, permission=0o755) render(ndppd_config, 'ndppd/ndppd.conf.j2', nat, permission=0o755) return None def apply(nat): if not nat: return None cmd(f'nft -f {nftables_nat66_config}') if 'deleted' in nat or not dict_search('source.rule', nat): cmd('systemctl stop ndppd') if os.path.isfile(ndppd_config): os.unlink(ndppd_config) else: cmd('systemctl restart ndppd') call_dependents() return None if __name__ == '__main__': try: check_kmod(k_mod) c = get_config() verify(c) generate(c) apply(c) except ConfigError as e: print(e) exit(1)