#!/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.configdict import dict_merge from vyos.configverify import verify_vrf from vyos.template import render from vyos.template import is_ipv4 from vyos.util import call from vyos.util import chmod_755 from vyos.validate import is_addr_assigned from vyos.xml import defaults from vyos import ConfigError from vyos import airbag airbag.enable() config_file = r'/etc/default/tftpd' def get_config(config=None): if config: conf = config else: conf = Config() base = ['service', 'tftp-server'] if not conf.exists(base): return None tftpd = conf.get_config_dict(base, key_mangling=('-', '_'), get_first_key=True) # We have gathered the dict representation of the CLI, but there are default # options which we need to update into the dictionary retrived. default_values = defaults(base) tftpd = dict_merge(default_values, tftpd) return tftpd def verify(tftpd): # bail out early - looks like removal from running config if not tftpd: return None # Configuring allowed clients without a server makes no sense if 'directory' not in tftpd: raise ConfigError('TFTP root directory must be configured!') if 'listen_address' not in tftpd: raise ConfigError('TFTP server listen address must be configured!') for address, address_config in tftpd['listen_address'].items(): if not is_addr_assigned(address): print(f'WARNING: TFTP server listen address "{address}" not ' \ 'assigned to any interface!') verify_vrf(address_config) 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 address, address_config in tftpd['listen_address'].items(): config = deepcopy(tftpd) port = tftpd['port'] if is_ipv4(address): config['listen_address'] = f'{address}:{port} -4' else: config['listen_address'] = f'[{address}]:{port} -6' if 'vrf' in address_config: config['vrf'] = address_config['vrf'] 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@*.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) chmod_755(tftp_root) # 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 address in tftpd['listen_address']: call(f'systemctl restart tftpd@{idx}.service') 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)