#!/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 <http://www.gnu.org/licenses/>. # # """ conf-mode script for 'system host-name' and 'system domain-name'. """ import os import re import sys import copy import glob import subprocess import argparse import jinja2 import vyos.util import vyos.hostsd_client from vyos.config import Config from vyos import ConfigError default_config_data = { 'hostname': 'vyos', 'domain_name': '', 'domain_search': [], 'nameserver': [], 'no_dhcp_ns': False } def get_config(): conf = Config() hosts = copy.deepcopy(default_config_data) if conf.exists("system host-name"): 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"): hosts['nameserver'] = conf.return_values("system name-server") if conf.exists("system disable-dhcp-nameservers"): hosts['no_dhcp_ns'] = True # system static-host-mapping hosts['static_host_mapping'] = [] if conf.exists('system static-host-mapping host-name'): for hn in conf.list_nodes('system static-host-mapping host-name'): mapping = {} mapping['host'] = hn mapping['address'] = conf.return_value('system static-host-mapping host-name {0} inet'.format(hn)) mapping['aliases'] = conf.return_values('system static-host-mapping host-name {0} alias'.format(hn)) hosts['static_host_mapping'].append(mapping) return hosts def verify(config): if config 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(config['hostname']): raise ConfigError('Invalid host name ' + config["hostname"]) # pattern $VAR(@) "^.{1,63}$" ; "invalid host-name length" length = len(config['hostname']) if length < 1 or length > 63: raise ConfigError( 'Invalid host-name length, must be less than 63 characters') # The search list is currently limited to six domains with a total of 256 characters. # https://linux.die.net/man/5/resolv.conf if len(config['domain_search']) > 6: raise ConfigError( 'The search list is currently limited to six domains') tmp = ' '.join(config['domain_search']) if len(tmp) > 256: raise ConfigError( 'The search list is currently limited to 256 characters') # static mappings alias hostname if config['static_host_mapping']: for m in config['static_host_mapping']: if not m['address']: raise ConfigError('IP address required for ' + m['host']) for a in m['aliases']: if not hostname_regex.match(a) and len(a) != 0: raise ConfigError('Invalid alias \'{0}\' in mapping {1}'.format(a, m['host'])) return None def generate(config): pass def apply(config): if config is None: return None ## Send the updated data to vyos-hostsd # vyos-hostsd uses "tags" to identify data sources tag = "static" try: client = vyos.hostsd_client.Client() # Check if disable-dhcp-nameservers is configured, and if yes - delete DNS servers added by DHCP if config['no_dhcp_ns']: client.delete_name_servers('dhcp-.+') client.set_host_name(config['hostname'], config['domain_name'], config['domain_search']) client.delete_name_servers(tag) client.add_name_servers(tag, config['nameserver']) client.delete_hosts(tag) client.add_hosts(tag, config['static_host_mapping']) 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 = subprocess.check_output(['hostnamectl', '--static']).decode().strip() os.system("hostnamectl set-hostname --static {0}".format(hostname_new)) # Restart services that use the hostname if hostname_new != hostname_old: os.system("systemctl restart rsyslog.service") # If SNMP is running, restart it too if os.system("pgrep snmpd > /dev/null") == 0: os.system("systemctl restart snmpd.service") # restart pdns if it is used if os.system("/usr/bin/rec_control ping >/dev/null 2>&1") == 0: os.system("/etc/init.d/pdns-recursor restart >/dev/null") return None if __name__ == '__main__': try: c = get_config() verify(c) generate(c) apply(c) except ConfigError as e: print(e) sys.exit(1)