#!/usr/bin/env python3 # # Copyright (C) 2018-2020 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 os import stat import pwd from copy import deepcopy from glob import glob from sys import exit from vyos.config import Config from vyos.validate import is_ipv4, is_addr_assigned from vyos import ConfigError from vyos.util import call from vyos.template import render from vyos import airbag airbag.enable() config_file = r'/etc/default/tftpd' default_config_data = { 'directory': '', 'allow_upload': False, 'port': '69', 'listen': [] } def get_config(): tftpd = deepcopy(default_config_data) conf = Config() base = ['service', 'tftp-server'] if not conf.exists(base): return None else: conf.set_level(base) if conf.exists(['directory']): tftpd['directory'] = conf.return_value(['directory']) if conf.exists(['allow-upload']): tftpd['allow_upload'] = True if conf.exists(['port']): tftpd['port'] = conf.return_value(['port']) if conf.exists(['listen-address']): tftpd['listen'] = conf.return_values(['listen-address']) return tftpd def verify(tftpd): # bail out early - looks like removal from running config if tftpd is None: return None # Configuring allowed clients without a server makes no sense if not tftpd['directory']: raise ConfigError('TFTP root directory must be configured!') if not tftpd['listen']: raise ConfigError('TFTP server listen address must be configured!') for addr in tftpd['listen']: if not is_addr_assigned(addr): print('WARNING: TFTP server listen address {0} not assigned to any interface!'.format(addr)) return None def generate(tftpd): # cleanup any available configuration file # files will be recreated on demand for i in glob(config_file + '*'): os.unlink(i) # bail out early - looks like removal from running config if tftpd is None: return None idx = 0 for listen in tftpd['listen']: config = deepcopy(tftpd) if is_ipv4(listen): config['listen'] = [listen + ":" + tftpd['port'] + " -4"] else: config['listen'] = ["[" + listen + "]" + tftpd['port'] + " -6"] file = config_file + str(idx) render(file, 'tftp-server/default.tmpl', config) idx = idx + 1 return None def apply(tftpd): # stop all services first - then we will decide call('systemctl stop tftpd@{0..20}.service') # bail out early - e.g. service deletion if tftpd is None: return None tftp_root = tftpd['directory'] if not os.path.exists(tftp_root): os.makedirs(tftp_root) os.chmod(tftp_root, stat.S_IRUSR|stat.S_IWUSR|stat.S_IXUSR|stat.S_IRGRP|stat.S_IXGRP|stat.S_IROTH|stat.S_IXOTH) # get UNIX uid for user 'tftp' tftp_uid = pwd.getpwnam('tftp').pw_uid tftp_gid = pwd.getpwnam('tftp').pw_gid # get UNIX uid for tftproot directory dir_uid = os.stat(tftp_root).st_uid dir_gid = os.stat(tftp_root).st_gid # adjust uid/gid of tftproot directory if files don't belong to user tftp if (tftp_uid != dir_uid) or (tftp_gid != dir_gid): os.chown(tftp_root, tftp_uid, tftp_gid) idx = 0 for listen in tftpd['listen']: call('systemctl restart tftpd@{0}.service'.format(idx)) idx = idx + 1 return None if __name__ == '__main__': try: c = get_config() verify(c) generate(c) apply(c) except ConfigError as e: print(e) exit(1)