#!/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 . # # """ conf-mode script for 'system host-name' and 'system domain-name'. """ import os import re import sys import subprocess from vyos.config import Config from vyos import ConfigError hosts_file = '/etc/hosts' hostname_regex = re.compile("^[A-Za-z0-9][-.A-Za-z0-9]*[A-Za-z0-9]$") local_addr = '127.0.1.1' # NOSONAR def get_config(): """Get configuration""" conf = Config() hostname = conf.return_value("system host-name") domain = conf.return_value("system domain-name") # No one likes fixups, but we really don't want VyOS fail to boot # if hostname is not in the config if not hostname: hostname = "vyos" if domain: fqdn = "{0}.{1}".format(hostname, domain) else: fqdn = hostname return {"hostname": hostname, "domain": domain, "fqdn": fqdn} def verify(config): """Verify configuration""" # check for invalid host # pattern $VAR(@) "^[[:alnum:]][-.[:alnum:]]*[[:alnum:]]$" ; "invalid host name $VAR(@)" 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') return None def generate(config): """Generate configuration files""" # read the hosts file with open(hosts_file, 'r') as f: hosts = f.read() # get the current hostname old_hostname = subprocess.check_output(['hostname']).decode().strip() # replace the local host line vyos_host_line_re = re.compile(r"({}\s+{}.*)".format(local_addr, old_hostname)) vyos_host_line = "{}\t{} # VyOS entry\n".format(local_addr, config["fqdn"]) if re.search(vyos_host_line_re, hosts): hosts = re.sub(vyos_host_line_re, vyos_host_line, hosts) else: # On boot (or after errors), the /etc/hosts file has no line for vyos hostname, # so we have to add it hosts = "{0}\n{1}".format(hosts, vyos_host_line) with open(hosts_file, 'w') as f: f.write(hosts) return None def apply(config): """Apply configuration""" os.system("hostnamectl set-hostname {0}".format(config["fqdn"])) # restart services that use the hostname os.system("systemctl restart rsyslog.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)