#!/usr/bin/env python3 # # Copyright (C) 2020-2023 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 . import os from netifaces import interfaces from sys import exit from vyos.config import Config from vyos.configdict import get_interface_dict from vyos.configdict import is_node_changed from vyos.configdict import is_source_interface from vyos.configverify import verify_vrf from vyos.configverify import verify_address from vyos.configverify import verify_bridge_delete from vyos.configverify import verify_mtu_ipv6 from vyos.configverify import verify_mirror_redirect from vyos.configverify import verify_source_interface from vyos.configverify import verify_bond_bridge_member from vyos.ifconfig import MACsecIf from vyos.ifconfig import Interface from vyos.template import render from vyos.utils.process import call from vyos.utils.dict import dict_search from vyos.utils.process import is_systemd_service_running from vyos import ConfigError from vyos import airbag airbag.enable() # XXX: wpa_supplicant works on the source interface wpa_suppl_conf = '/run/wpa_supplicant/{source_interface}.conf' # Constants ## gcm-aes-128 requires a 128bit long key - 32 characters (string) = 16byte = 128bit GCM_AES_128_LEN: int = 32 GCM_128_KEY_ERROR = 'gcm-aes-128 requires a 128bit long key!' ## gcm-aes-256 requires a 256bit long key - 64 characters (string) = 32byte = 256bit GCM_AES_256_LEN: int = 64 GCM_256_KEY_ERROR = 'gcm-aes-256 requires a 256bit long key!' def get_config(config=None): """ Retrive CLI config as dictionary. Dictionary can never be empty, as at least the interface name will be added or a deleted flag """ if config: conf = config else: conf = Config() base = ['interfaces', 'macsec'] ifname, macsec = get_interface_dict(conf, base) # Check if interface has been removed if 'deleted' in macsec: source_interface = conf.return_effective_value(base + [ifname, 'source-interface']) macsec.update({'source_interface': source_interface}) if is_node_changed(conf, base + [ifname, 'security']): macsec.update({'shutdown_required': {}}) if is_node_changed(conf, base + [ifname, 'source_interface']): macsec.update({'shutdown_required': {}}) if 'source_interface' in macsec: tmp = is_source_interface(conf, macsec['source_interface'], ['macsec', 'pseudo-ethernet']) if tmp and tmp != ifname: macsec.update({'is_source_interface' : tmp}) return macsec def verify(macsec): if 'deleted' in macsec: verify_bridge_delete(macsec) return None verify_source_interface(macsec) verify_vrf(macsec) verify_mtu_ipv6(macsec) verify_address(macsec) verify_bond_bridge_member(macsec) verify_mirror_redirect(macsec) if dict_search('security.cipher', macsec) == None: raise ConfigError('Cipher suite must be set for MACsec "{ifname}"'.format(**macsec)) if dict_search('security.encrypt', macsec) != None: # Check that only static or MKA config is present if dict_search('security.static', macsec) != None and (dict_search('security.mka.cak', macsec) != None or dict_search('security.mka.ckn', macsec) != None): raise ConfigError('Only static or MKA can be used!') # Logic to check static configuration if dict_search('security.static', macsec) != None: # tx-key must be defined if dict_search('security.static.key', macsec) == None: raise ConfigError('Static MACsec tx-key must be defined.') tx_len = len(dict_search('security.static.key', macsec)) if dict_search('security.cipher', macsec) == 'gcm-aes-128' and tx_len != GCM_AES_128_LEN: raise ConfigError(GCM_128_KEY_ERROR) if dict_search('security.cipher', macsec) == 'gcm-aes-256' and tx_len != GCM_AES_256_LEN: raise ConfigError(GCM_256_KEY_ERROR) # Make sure at least one peer is defined if 'peer' not in macsec['security']['static']: raise ConfigError('Must have at least one peer defined for static MACsec') # For every enabled peer, make sure a MAC and rx-key is defined for peer, peer_config in macsec['security']['static']['peer'].items(): if 'disable' not in peer_config and ('mac' not in peer_config or 'key' not in peer_config): raise ConfigError('Every enabled MACsec static peer must have a MAC address and rx-key defined.') # check rx-key length against cipher suite rx_len = len(peer_config['key']) if dict_search('security.cipher', macsec) == 'gcm-aes-128' and rx_len != GCM_AES_128_LEN: raise ConfigError(GCM_128_KEY_ERROR) if dict_search('security.cipher', macsec) == 'gcm-aes-256' and rx_len != GCM_AES_256_LEN: raise ConfigError(GCM_256_KEY_ERROR) # Logic to check MKA configuration else: if dict_search('security.mka.cak', macsec) == None or dict_search('security.mka.ckn', macsec) == None: raise ConfigError('Missing mandatory MACsec security keys as encryption is enabled!') cak_len = len(dict_search('security.mka.cak', macsec)) if dict_search('security.cipher', macsec) == 'gcm-aes-128' and cak_len != GCM_AES_128_LEN: raise ConfigError(GCM_128_KEY_ERROR) elif dict_search('security.cipher', macsec) == 'gcm-aes-256' and cak_len != GCM_AES_256_LEN: raise ConfigError(GCM_256_KEY_ERROR) if 'source_interface' in macsec: # MACsec adds a 40 byte overhead (32 byte MACsec + 8 bytes VLAN 802.1ad # and 802.1q) - we need to check the underlaying MTU if our configured # MTU is at least 40 bytes less then the MTU of our physical interface. lower_mtu = Interface(macsec['source_interface']).get_mtu() if lower_mtu < (int(macsec['mtu']) + 40): raise ConfigError('MACsec overhead does not fit into underlaying device MTU,\n' \ f'{lower_mtu} bytes is too small!') return None def generate(macsec): # Only generate wpa_supplicant config if using MKA if dict_search('security.static', macsec) == None: render(wpa_suppl_conf.format(**macsec), 'macsec/wpa_supplicant.conf.j2', macsec) return None def apply(macsec): systemd_service = 'wpa_supplicant-macsec@{source_interface}'.format(**macsec) # Remove macsec interface on deletion or mandatory parameter change if 'deleted' in macsec or 'shutdown_required' in macsec: call(f'systemctl stop {systemd_service}') if macsec['ifname'] in interfaces(): tmp = MACsecIf(macsec['ifname']) tmp.remove() if 'deleted' in macsec: # delete configuration on interface removal if os.path.isfile(wpa_suppl_conf.format(**macsec)): os.unlink(wpa_suppl_conf.format(**macsec)) return None # It is safe to "re-create" the interface always, there is a sanity # check that the interface will only be create if its non existent i = MACsecIf(**macsec) i.update(macsec) # Only reload/restart if using MKA if dict_search('security.mka.cak', macsec): if not is_systemd_service_running(systemd_service) or 'shutdown_required' in macsec: call(f'systemctl reload-or-restart {systemd_service}') return None if __name__ == '__main__': try: c = get_config() verify(c) generate(c) apply(c) except ConfigError as e: print(e) exit(1)