#!/usr/bin/env python3 # # Copyright (C) 2020-2022 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 from sys import exit from glob import glob from vyos.config import Config from vyos.template import render_to_string from vyos.utils.dict import dict_search from vyos.utils.file import read_file from vyos.utils.system import sysctl_write from vyos.configverify import verify_interface_exists from vyos import ConfigError from vyos import frr from vyos import airbag airbag.enable() config_file = r'/tmp/ldpd.frr' def get_config(config=None): if config: conf = config else: conf = Config() base = ['protocols', 'mpls'] mpls = conf.get_config_dict(base, key_mangling=('-', '_'), get_first_key=True) return mpls def verify(mpls): # If no config, then just bail out early. if not mpls: return None if 'interface' in mpls: for interface in mpls['interface']: verify_interface_exists(interface) # Checks to see if LDP is properly configured if 'ldp' in mpls: # If router ID not defined if 'router_id' not in mpls['ldp']: raise ConfigError('Router ID missing. An LDP router id is mandatory!') # If interface not set if 'interface' not in mpls['ldp']: raise ConfigError('LDP interfaces are missing. An LDP interface is mandatory!') # If transport addresses are not set if not dict_search('ldp.discovery.transport_ipv4_address', mpls) and \ not dict_search('ldp.discovery.transport_ipv6_address', mpls): raise ConfigError('LDP transport address missing!') return None def generate(mpls): # If there's no MPLS config generated, create dictionary key with no value. if not mpls or 'deleted' in mpls: return None mpls['frr_ldpd_config'] = render_to_string('frr/ldpd.frr.j2', mpls) return None def apply(mpls): ldpd_damon = 'ldpd' # Save original configuration prior to starting any commit actions frr_cfg = frr.FRRConfig() frr_cfg.load_configuration(ldpd_damon) frr_cfg.modify_section(f'^mpls ldp', stop_pattern='^exit', remove_stop_mark=True) if 'frr_ldpd_config' in mpls: frr_cfg.add_before(frr.default_add_before, mpls['frr_ldpd_config']) frr_cfg.commit_configuration(ldpd_damon) # Set number of entries in the platform label tables labels = '0' if 'interface' in mpls: labels = '1048575' sysctl_write('net.mpls.platform_labels', labels) # Check for changes in global MPLS options if 'parameters' in mpls: # Choose whether to copy IP TTL to MPLS header TTL if 'no_propagate_ttl' in mpls['parameters']: sysctl_write('net.mpls.ip_ttl_propagate', 0) # Choose whether to limit maximum MPLS header TTL if 'maximum_ttl' in mpls['parameters']: ttl = mpls['parameters']['maximum_ttl'] sysctl_write('net.mpls.default_ttl', ttl) else: # Set default global MPLS options if not defined. sysctl_write('net.mpls.ip_ttl_propagate', 1) sysctl_write('net.mpls.default_ttl', 255) # Enable and disable MPLS processing on interfaces per configuration if 'interface' in mpls: system_interfaces = [] # Populate system interfaces list with local MPLS capable interfaces for interface in glob('/proc/sys/net/mpls/conf/*'): system_interfaces.append(os.path.basename(interface)) # This is where the comparison is done on if an interface needs to be enabled/disabled. for system_interface in system_interfaces: interface_state = read_file(f'/proc/sys/net/mpls/conf/{system_interface}/input') if '1' in interface_state: if system_interface not in mpls['interface']: system_interface = system_interface.replace('.', '/') sysctl_write(f'net.mpls.conf.{system_interface}.input', 0) elif '0' in interface_state: if system_interface in mpls['interface']: system_interface = system_interface.replace('.', '/') sysctl_write(f'net.mpls.conf.{system_interface}.input', 1) else: system_interfaces = [] # If MPLS interfaces are not configured, set MPLS processing disabled for interface in glob('/proc/sys/net/mpls/conf/*'): system_interfaces.append(os.path.basename(interface)) for system_interface in system_interfaces: system_interface = system_interface.replace('.', '/') sysctl_write(f'net.mpls.conf.{system_interface}.input', 0) return None if __name__ == '__main__': try: c = get_config() verify(c) generate(c) apply(c) except ConfigError as e: print(e) exit(1)