#!/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 sys import argv from vyos.config import Config from vyos.configdict import dict_merge from vyos.configdict import node_changed from vyos.configverify import verify_common_route_maps from vyos.configverify import verify_interface_exists from vyos.ifconfig import Interface from vyos.util import dict_search from vyos.util import get_interface_config from vyos.template import render_to_string from vyos.xml import defaults from vyos import ConfigError from vyos import frr from vyos import airbag airbag.enable() def get_config(config=None): if config: conf = config else: conf = Config() vrf = None if len(argv) > 1: vrf = argv[1] base_path = ['protocols', 'isis'] # eqivalent of the C foo ? 'a' : 'b' statement base = vrf and ['vrf', 'name', vrf, 'protocols', 'isis'] or base_path isis = conf.get_config_dict(base, key_mangling=('-', '_'), get_first_key=True) # Assign the name of our VRF context. This MUST be done before the return # statement below, else on deletion we will delete the default instance # instead of the VRF instance. if vrf: isis['vrf'] = vrf # FRR has VRF support for different routing daemons. As interfaces belong # to VRFs - or the global VRF, we need to check for changed interfaces so # that they will be properly rendered for the FRR config. Also this eases # removal of interfaces from the running configuration. interfaces_removed = node_changed(conf, base + ['interface']) if interfaces_removed: isis['interface_removed'] = list(interfaces_removed) # Bail out early if configuration tree does not exist if not conf.exists(base): isis.update({'deleted' : ''}) return isis # We have gathered the dict representation of the CLI, but there are default # options which we need to update into the dictionary retrived. # XXX: Note that we can not call defaults(base), as defaults does not work # on an instance of a tag node. As we use the exact same CLI definition for # both the non-vrf and vrf version this is absolutely safe! default_values = defaults(base_path) # merge in default values isis = dict_merge(default_values, isis) # We also need some additional information from the config, prefix-lists # and route-maps for instance. They will be used in verify(). # # XXX: one MUST always call this without the key_mangling() option! See # vyos.configverify.verify_common_route_maps() for more information. tmp = conf.get_config_dict(['policy']) # Merge policy dict into "regular" config dict isis = dict_merge(tmp, isis) return isis def verify(isis): # bail out early - looks like removal from running config if not isis or 'deleted' in isis: return None if 'net' not in isis: raise ConfigError('Network entity is mandatory!') # last byte in IS-IS area address must be 0 tmp = isis['net'].split('.') if int(tmp[-1]) != 0: raise ConfigError('Last byte of IS-IS network entity title must always be 0!') verify_common_route_maps(isis) # If interface not set if 'interface' not in isis: raise ConfigError('Interface used for routing updates is mandatory!') for interface in isis['interface']: verify_interface_exists(interface) # Interface MTU must be >= configured lsp-mtu mtu = Interface(interface).get_mtu() area_mtu = isis['lsp_mtu'] # Recommended maximum PDU size = interface MTU - 3 bytes recom_area_mtu = mtu - 3 if mtu < int(area_mtu) or int(area_mtu) > recom_area_mtu: raise ConfigError(f'Interface {interface} has MTU {mtu}, ' \ f'current area MTU is {area_mtu}! \n' \ f'Recommended area lsp-mtu {recom_area_mtu} or less ' \ '(calculated on MTU size).') if 'vrf' in isis: # If interface specific options are set, we must ensure that the # interface is bound to our requesting VRF. Due to the VyOS # priorities the interface is bound to the VRF after creation of # the VRF itself, and before any routing protocol is configured. vrf = isis['vrf'] tmp = get_interface_config(interface) if 'master' not in tmp or tmp['master'] != vrf: raise ConfigError(f'Interface {interface} is not a member of VRF {vrf}!') # If md5 and plaintext-password set at the same time for password in ['area_password', 'domain_password']: if password in isis: if {'md5', 'plaintext_password'} <= set(isis[password]): tmp = password.replace('_', '-') raise ConfigError(f'Can use either md5 or plaintext-password for {tmp}!') # If one param from delay set, but not set others if 'spf_delay_ietf' in isis: required_timers = ['holddown', 'init_delay', 'long_delay', 'short_delay', 'time_to_learn'] exist_timers = [] for elm_timer in required_timers: if elm_timer in isis['spf_delay_ietf']: exist_timers.append(elm_timer) exist_timers = set(required_timers).difference(set(exist_timers)) if len(exist_timers) > 0: raise ConfigError('All types of spf-delay must be configured. Missing: ' + ', '.join(exist_timers).replace('_', '-')) # If Redistribute set, but level don't set if 'redistribute' in isis: proc_level = isis.get('level','').replace('-','_') for afi in ['ipv4', 'ipv6']: if afi not in isis['redistribute']: continue for proto, proto_config in isis['redistribute'][afi].items(): if 'level_1' not in proto_config and 'level_2' not in proto_config: raise ConfigError(f'Redistribute level-1 or level-2 should be specified in ' \ f'"protocols isis {process} redistribute {afi} {proto}"!') for redistr_level, redistr_config in proto_config.items(): if proc_level and proc_level != 'level_1_2' and proc_level != redistr_level: raise ConfigError(f'"protocols isis {process} redistribute {afi} {proto} {redistr_level}" ' \ f'can not be used with \"protocols isis {process} level {proc_level}\"') # Segment routing checks if dict_search('segment_routing.global_block', isis): g_high_label_value = dict_search('segment_routing.global_block.high_label_value', isis) g_low_label_value = dict_search('segment_routing.global_block.low_label_value', isis) # If segment routing global block high or low value is blank, throw error if not (g_low_label_value or g_high_label_value): raise ConfigError('Segment routing global-block requires both low and high value!') # If segment routing global block low value is higher than the high value, throw error if int(g_low_label_value) > int(g_high_label_value): raise ConfigError('Segment routing global-block low value must be lower than high value') if dict_search('segment_routing.local_block', isis): if dict_search('segment_routing.global_block', isis) == None: raise ConfigError('Segment routing local-block requires global-block to be configured!') l_high_label_value = dict_search('segment_routing.local_block.high_label_value', isis) l_low_label_value = dict_search('segment_routing.local_block.low_label_value', isis) # If segment routing local-block high or low value is blank, throw error if not (l_low_label_value or l_high_label_value): raise ConfigError('Segment routing local-block requires both high and low value!') # If segment routing local-block low value is higher than the high value, throw error if int(l_low_label_value) > int(l_high_label_value): raise ConfigError('Segment routing local-block low value must be lower than high value') # local-block most live outside global block global_range = range(int(g_low_label_value), int(g_high_label_value) +1) local_range = range(int(l_low_label_value), int(l_high_label_value) +1) # Check for overlapping ranges if list(set(global_range) & set(local_range)): raise ConfigError(f'Segment-Routing Global Block ({g_low_label_value}/{g_high_label_value}) '\ f'conflicts with Local Block ({l_low_label_value}/{l_high_label_value})!') return None def generate(isis): if not isis or 'deleted' in isis: return None isis['protocol'] = 'isis' # required for frr/vrf.route-map.frr.j2 isis['frr_zebra_config'] = render_to_string('frr/vrf.route-map.frr.j2', isis) isis['frr_isisd_config'] = render_to_string('frr/isisd.frr.j2', isis) return None def apply(isis): isis_daemon = 'isisd' zebra_daemon = 'zebra' # Save original configuration prior to starting any commit actions frr_cfg = frr.FRRConfig() # The route-map used for the FIB (zebra) is part of the zebra daemon frr_cfg.load_configuration(zebra_daemon) frr_cfg.modify_section('(\s+)?ip protocol isis route-map [-a-zA-Z0-9.]+', stop_pattern='(\s|!)') if 'frr_zebra_config' in isis: frr_cfg.add_before(frr.default_add_before, isis['frr_zebra_config']) frr_cfg.commit_configuration(zebra_daemon) # Generate empty helper string which can be ammended to FRR commands, it # will be either empty (default VRF) or contain the "vrf <name" statement vrf = '' if 'vrf' in isis: vrf = ' vrf ' + isis['vrf'] frr_cfg.load_configuration(isis_daemon) frr_cfg.modify_section(f'^router isis VyOS{vrf}', stop_pattern='^exit', remove_stop_mark=True) for key in ['interface', 'interface_removed']: if key not in isis: continue for interface in isis[key]: frr_cfg.modify_section(f'^interface {interface}{vrf}', stop_pattern='^exit', remove_stop_mark=True) if 'frr_isisd_config' in isis: frr_cfg.add_before(frr.default_add_before, isis['frr_isisd_config']) frr_cfg.commit_configuration(isis_daemon) return None if __name__ == '__main__': try: c = get_config() verify(c) generate(c) apply(c) except ConfigError as e: print(e) exit(1)