diff options
Diffstat (limited to 'src/conf_mode/interfaces_macsec.py')
| -rwxr-xr-x | src/conf_mode/interfaces_macsec.py | 207 |
1 files changed, 207 insertions, 0 deletions
diff --git a/src/conf_mode/interfaces_macsec.py b/src/conf_mode/interfaces_macsec.py new file mode 100755 index 000000000..0a927ac88 --- /dev/null +++ b/src/conf_mode/interfaces_macsec.py @@ -0,0 +1,207 @@ +#!/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 <http://www.gnu.org/licenses/>. + +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.mka.cak', macsec): + 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) |