#!/usr/bin/env python3 # # Copyright (C) 2018 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 . # # import sys import os import jinja2 import ipaddress import copy from vyos.config import Config from vyos import ConfigError config_file = r'/etc/ntp.conf' # Please be careful if you edit the template. config_tmpl = """ ### Autogenerated by ntp.py ### # # Non-configurable defaults # driftfile /var/lib/ntp/ntp.drift # By default, only allow ntpd to query time sources, ignore any incoming requests restrict default noquery nopeer notrap nomodify # Local users have unrestricted access, allowing reconfiguration via ntpdc restrict 127.0.0.1 restrict -6 ::1 # Do not listen on any interface address by default interface ignore wildcard # # Configurable section # {% if servers -%} {% for s in servers -%} # Server configuration for: {{ s.name }} server {{ s.name }} iburst {{ s.options | join(" ") }} {% endfor -%} {% endif %} {% if allowed_networks -%} {% for n in allowed_networks -%} # Client configuration for network: {{ n.network }} restrict {{ n.address }} mask {{ n.netmask }} nomodify notrap nopeer {% endfor -%} {% endif %} {% if listen_address -%} # NTP should listen on configured addresses only {% for a in listen_address -%} interface listen {{ a }} {% endfor -%} {% endif %} """ default_config_data = { 'servers': [], 'allowed_networks': [], 'listen_address': [] } def get_config(): ntp = copy.deepcopy(default_config_data) conf = Config() if not conf.exists('system ntp'): return None else: conf.set_level('system ntp') if conf.exists('allow-clients address'): networks = conf.return_values('allow-clients address') for n in networks: addr = ipaddress.ip_network(n) net = { "network" : n, "address" : addr.network_address, "netmask" : addr.netmask } ntp['allowed_networks'].append(net) if conf.exists('listen-address'): ntp['listen_address'] = conf.return_values('listen-address') if conf.exists('server'): for node in conf.list_nodes('server'): options = [] server = { "name": node, "options": [] } if conf.exists('server {0} noselect'.format(node)): options.append('noselect') if conf.exists('server {0} preempt'.format(node)): options.append('preempt') if conf.exists('server {0} prefer'.format(node)): options.append('prefer') server['options'] = options ntp['servers'].append(server) return ntp def verify(ntp): # bail out early - looks like removal from running config if ntp is None: return None # Configuring allowed clients without a server makes no sense if len(ntp['allowed_networks']) and not len(ntp['servers']): raise ConfigError('NTP server not configured') for n in ntp['allowed_networks']: try: addr = ipaddress.ip_network( n['network'] ) break except ValueError: raise ConfigError("{0} does not appear to be a valid IPv4 or IPv6 network, check host bits!".format(n['network'])) return None def generate(ntp): # bail out early - looks like removal from running config if ntp is None: return None tmpl = jinja2.Template(config_tmpl) config_text = tmpl.render(ntp) with open(config_file, 'w') as f: f.write(config_text) return None def apply(ntp): if ntp is not None: os.system('sudo systemctl restart ntp.service') else: # NTP support is removed in the commit os.system('sudo systemctl stop ntp.service') 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) sys.exit(1)