#!/usr/bin/env python3 # # Copyright (C) 2018-2021 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 re import sys import copy import vyos.util import vyos.hostsd_client from vyos.base import Warning from vyos.config import Config from vyos.ifconfig import Section from vyos.template import is_ip from vyos.util import cmd from vyos.util import call from vyos.util import process_named_running from vyos import ConfigError from vyos import airbag airbag.enable() default_config_data = { 'hostname': 'vyos', 'domain_name': '', 'domain_search': [], 'nameserver': [], 'nameservers_dhcp_interfaces': {}, 'static_host_mapping': {} } hostsd_tag = 'system' def get_config(config=None): if config: conf = config else: conf = Config() hosts = copy.deepcopy(default_config_data) hosts['hostname'] = conf.return_value(['system', 'host-name']) # This may happen if the config is not loaded yet, # e.g. if run by cloud-init if not hosts['hostname']: hosts['hostname'] = default_config_data['hostname'] if conf.exists(['system', 'domain-name']): hosts['domain_name'] = conf.return_value(['system', 'domain-name']) hosts['domain_search'].append(hosts['domain_name']) for search in conf.return_values(['system', 'domain-search', 'domain']): hosts['domain_search'].append(search) if conf.exists(['system', 'name-server']): for ns in conf.return_values(['system', 'name-server']): if is_ip(ns): hosts['nameserver'].append(ns) else: tmp = '' if_type = Section.section(ns) if conf.exists(['interfaces', if_type, ns, 'address']): tmp = conf.return_values(['interfaces', if_type, ns, 'address']) hosts['nameservers_dhcp_interfaces'].update({ ns : tmp }) # system static-host-mapping for hn in conf.list_nodes(['system', 'static-host-mapping', 'host-name']): hosts['static_host_mapping'][hn] = {} hosts['static_host_mapping'][hn]['address'] = conf.return_values(['system', 'static-host-mapping', 'host-name', hn, 'inet']) hosts['static_host_mapping'][hn]['aliases'] = conf.return_values(['system', 'static-host-mapping', 'host-name', hn, 'alias']) return hosts def verify(hosts): if hosts is None: return None # pattern $VAR(@) "^[[:alnum:]][-.[:alnum:]]*[[:alnum:]]$" ; "invalid host name $VAR(@)" hostname_regex = re.compile("^[A-Za-z0-9][-.A-Za-z0-9]*[A-Za-z0-9]$") if not hostname_regex.match(hosts['hostname']): raise ConfigError('Invalid host name ' + hosts["hostname"]) # pattern $VAR(@) "^.{1,63}$" ; "invalid host-name length" length = len(hosts['hostname']) if length < 1 or length > 63: raise ConfigError( 'Invalid host-name length, must be less than 63 characters') all_static_host_mapping_addresses = [] # static mappings alias hostname for host, hostprops in hosts['static_host_mapping'].items(): if not hostprops['address']: raise ConfigError(f'IP address required for static-host-mapping "{host}"') all_static_host_mapping_addresses.append(hostprops['address']) for a in hostprops['aliases']: if not hostname_regex.match(a) and len(a) != 0: raise ConfigError(f'Invalid alias "{a}" in static-host-mapping "{host}"') for interface, interface_config in hosts['nameservers_dhcp_interfaces'].items(): # Warnin user if interface does not have DHCP or DHCPv6 configured if not set(interface_config).intersection(['dhcp', 'dhcpv6']): Warning(f'"{interface}" is not a DHCP interface but uses DHCP name-server option!') return None def generate(config): pass def apply(config): if config is None: return None ## Send the updated data to vyos-hostsd try: hc = vyos.hostsd_client.Client() hc.set_host_name(config['hostname'], config['domain_name']) hc.delete_search_domains([hostsd_tag]) if config['domain_search']: hc.add_search_domains({hostsd_tag: config['domain_search']}) hc.delete_name_servers([hostsd_tag]) if config['nameserver']: hc.add_name_servers({hostsd_tag: config['nameserver']}) # add our own tag's (system) nameservers and search to resolv.conf hc.delete_name_server_tags_system(hc.get_name_server_tags_system()) hc.add_name_server_tags_system([hostsd_tag]) # this will add the dhcp client nameservers to resolv.conf for intf in config['nameservers_dhcp_interfaces']: hc.add_name_server_tags_system([f'dhcp-{intf}', f'dhcpv6-{intf}']) hc.delete_hosts([hostsd_tag]) if config['static_host_mapping']: hc.add_hosts({hostsd_tag: config['static_host_mapping']}) hc.apply() except vyos.hostsd_client.VyOSHostsdError as e: raise ConfigError(str(e)) ## Actually update the hostname -- vyos-hostsd doesn't do that # No domain name -- the Debian way. hostname_new = config['hostname'] # rsyslog runs into a race condition at boot time with systemd # restart rsyslog only if the hostname changed. hostname_old = cmd('hostnamectl --static') call(f'hostnamectl set-hostname --static {hostname_new}') # Restart services that use the hostname if hostname_new != hostname_old: call("systemctl restart rsyslog.service") # If SNMP is running, restart it too if process_named_running('snmpd'): call('systemctl restart snmpd.service') return None if __name__ == '__main__': try: c = get_config() verify(c) generate(c) apply(c) except ConfigError as e: print(e) sys.exit(1)