diff options
Diffstat (limited to 'src/services')
| -rwxr-xr-x | src/services/vyos-netlinkd | 169 |
1 files changed, 169 insertions, 0 deletions
diff --git a/src/services/vyos-netlinkd b/src/services/vyos-netlinkd new file mode 100755 index 000000000..647241276 --- /dev/null +++ b/src/services/vyos-netlinkd @@ -0,0 +1,169 @@ +#!/usr/bin/env python3 +# +# Copyright VyOS maintainers and contributors <maintainers@vyos.io> +# +# 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 re +import sys +import syslog +import signal +import select + +from pyroute2 import IPRoute # pylint: disable = no-name-in-module +from pyroute2 import NetlinkError # pylint: disable = no-name-in-module +from time import sleep +from typing import Optional + +from vyos.configquery import op_mode_config_dict +from vyos.ifconfig import Section +from vyos.utils.boot import boot_configuration_complete +from vyos.utils.commit import commit_in_progress +from vyos.utils.dict import dict_search +from vyos.utils.process import cmd +from vyos.utils.process import is_systemd_service_active + +running = True + +# compile regex once during startup for fast match +IFACE_RE = re.compile(r"^(?:eth|br|bond|wlan)") + +def match_iface(ifname: str) -> bool: + """ Helper function returning true if interface name is a match for further + processing (e.g. restart of DHCP(v6) client) + """ + return IFACE_RE.match(ifname) is not None + +def sigterm_handler(signo, frame): + global running + running = False + sig = signal.Signals(signo) + syslog.syslog(syslog.LOG_INFO, f'Received signal {sig.name} - shutting down...') + +def _handle_dhcp_events(config_dict: dict, operstate: Optional[str], ifname: str) -> None: + systemdV4_service = f'dhclient@{ifname}.service' + systemdV6_service = f'dhcp6c@{ifname}.service' + + # Only handle explicit UP/DOWN state transitions; ignore other kernel states. + if operstate not in ['UP', 'DOWN']: + return None + + if operstate == 'DOWN': + # Interface moved state to down + if is_systemd_service_active(systemdV4_service): + syslog.syslog(syslog.LOG_DEBUG, f'Stopping {systemdV4_service}...') + cmd(f'systemctl stop {systemdV4_service}') + if is_systemd_service_active(systemdV6_service): + syslog.syslog(syslog.LOG_DEBUG, f'Stopping {systemdV6_service}...') + cmd(f'systemctl stop {systemdV6_service}') + + elif operstate == 'UP': + v6_restart = False + interface_path = Section.get_config_path(ifname, delimiter='.') + if tmp := dict_search(f'{interface_path}.address', config_dict): + # Always (re-)start the DHCP(v6) client service. If the DHCP(v6) client + # is already running - which could happen if the interface is re- + # configured in operational down state, it will have an exponential backoff + # time increasing while not receiving a DHCP(v6) reply. + # + # To make the interface instantly available, and as for a DHCP(v6) lease + # we will re-start the service and thus cancel the backoff time. + if 'dhcp' in tmp: + syslog.syslog(syslog.LOG_DEBUG, f'Restarting {systemdV4_service}...') + cmd(f'systemctl restart {systemdV4_service}') + if 'dhcpv6' in tmp: + v6_restart = True + + if dict_search(f'{interface_path}.dhcpv6_options.pd', config_dict): + v6_restart = True + + if v6_restart: + syslog.syslog(syslog.LOG_DEBUG, f'Restarting {systemdV6_service}...') + cmd(f'systemctl restart {systemdV6_service}') + + return None + +def main(): + syslog.openlog(ident="vyos-netlinkd", + logoption=syslog.LOG_PID, + facility=syslog.LOG_DAEMON) + syslog.syslog(syslog.LOG_INFO, "VyOS Netlink listener daemon started.") + + ipr = IPRoute() + ipr.bind() + fd = ipr.fileno() + + global running + while running: + if not boot_configuration_complete(): + syslog.syslog(syslog.LOG_INFO, 'System bootup not yet finished...') + sleep(5) + continue + + try: + # Wait for up to 1 second for a netlink message + rlist, _, _ = select.select([fd], [], [], 1.0) + if not rlist: + # timeout - retry + continue + + # Receive and process any messages + for message in ipr.get(): + # Wait for commit to complete + while commit_in_progress(): + sleep(0.250) + + config_dict = op_mode_config_dict(['interfaces'], + key_mangling=('-', '_'), + get_first_key=True) + + # Parse NETLINK message + match message['event']: + # Message received during interface creation or modification + # e.g. link up/down. + case 'RTM_NEWLINK': + attrs = dict(message.get('attrs', [])) + ifname = attrs.get('IFLA_IFNAME', None) + mac = attrs.get('IFLA_ADDRESS', '<unknown>') + operstate = attrs.get('IFLA_OPERSTATE', None) + syslog.syslog(syslog.LOG_DEBUG, + f'RTM_NEWLINK -> {ifname}, state={operstate}, mac={mac}') + + # Bail out early - no interface name in the message + if not ifname: + continue + # Bail out early - not interested in interface type + if not match_iface(ifname): + continue + + _handle_dhcp_events(config_dict, operstate, ifname) + + # Deletion of a network link which has been previously added to the kernel + case 'RTM_DELLINK': + pass + + except NetlinkError as e: + syslog.syslog(syslog.LOG_ERR, f'Netlink error: {e}') + except Exception as e: + syslog.syslog(syslog.LOG_ERR, f'Unhandled exception: {e}') + except KeyboardInterrupt: + break + + ipr.close() + syslog.syslog(syslog.LOG_INFO, 'Netlink listener daemon stopped.') + sys.exit(0) + +if __name__ == "__main__": + signal.signal(signal.SIGTERM, sigterm_handler) + signal.signal(signal.SIGINT, sigterm_handler) + main() |