#!/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 import re from pathlib import Path from vyos.config import Config from vyos.utils.process import call from vyos.utils.file import read_file from vyos.utils.file import write_file from vyos.template import render from vyos import ConfigError from vyos import airbag airbag.enable() by_bus_dir = '/dev/serial/by-bus' def get_config(config=None): if config: conf = config else: conf = Config() base = ['system', 'console'] # retrieve configuration at once console = conf.get_config_dict(base, get_first_key=True) # bail out early if no serial console is configured if 'device' not in console: return console for device, device_config in console['device'].items(): if 'speed' not in device_config and device.startswith('hvc'): # XEN console has a different default console speed console['device'][device]['speed'] = 38400 console = conf.merge_defaults(console, recursive=True) return console def verify(console): if not console or 'device' not in console: return None for device in console['device']: if device.startswith('usb'): # It is much easiert to work with the native ttyUSBn name when using # getty, but that name may change across reboots - depending on the # amount of connected devices. We will resolve the fixed device name # to its dynamic device file - and create a new dict entry for it. by_bus_device = f'{by_bus_dir}/{device}' # If the device name still starts with usbXXX no matching tty was found # and it can not be used as a serial interface if not os.path.isdir(by_bus_dir) or not os.path.exists(by_bus_device): raise ConfigError(f'Device {device} does not support beeing used as tty') return None def generate(console): base_dir = '/run/systemd/system' # Remove all serial-getty configuration files in advance for root, dirs, files in os.walk(base_dir): for basename in files: if 'serial-getty' in basename: call(f'systemctl stop {basename}') os.unlink(os.path.join(root, basename)) if not console or 'device' not in console: return None # replace keys in the config for ttyUSB items to use them in `apply()` later for device in console['device'].copy(): if device.startswith('usb'): # It is much easiert to work with the native ttyUSBn name when using # getty, but that name may change across reboots - depending on the # amount of connected devices. We will resolve the fixed device name # to its dynamic device file - and create a new dict entry for it. by_bus_device = f'{by_bus_dir}/{device}' if os.path.isdir(by_bus_dir) and os.path.exists(by_bus_device): device_updated = os.path.basename(os.readlink(by_bus_device)) # replace keys in the config to use them in `apply()` later console['device'][device_updated] = console['device'][device] del console['device'][device] else: raise ConfigError(f'Device {device} does not support beeing used as tty') for device, device_config in console['device'].items(): config_file = base_dir + f'/serial-getty@{device}.service' Path(f'{base_dir}/getty.target.wants').mkdir(exist_ok=True) getty_wants_symlink = base_dir + f'/getty.target.wants/serial-getty@{device}.service' render(config_file, 'getty/serial-getty.service.j2', device_config) os.symlink(config_file, getty_wants_symlink) # GRUB # For existing serial line change speed (if necessary) # Only applys to ttyS0 if 'ttyS0' not in console['device']: return None speed = console['device']['ttyS0']['speed'] grub_config = '/boot/grub/grub.cfg' if not os.path.isfile(grub_config): return None lines = read_file(grub_config).split('\n') p = re.compile(r'^(.* console=ttyS0),[0-9]+(.*)$') write = False newlines = [] for line in lines: if line.startswith('serial --unit'): newline = f'serial --unit=0 --speed={speed}' elif p.match(line): newline = '{},{}{}'.format(p.search(line)[1], speed, p.search(line)[2]) else: newline = line if newline != line: write = True newlines.append(newline) newlines.append('') if write: write_file(grub_config, '\n'.join(newlines)) return None def apply(console): # Reset screen blanking call('/usr/bin/setterm -blank 0 -powersave off -powerdown 0 -term linux </dev/tty1 >/dev/tty1 2>&1') # Reload systemd manager configuration call('systemctl daemon-reload') if not console: return None if 'powersave' in console.keys(): # Configure screen blank powersaving on VGA console call('/usr/bin/setterm -blank 15 -powersave powerdown -powerdown 60 -term linux </dev/tty1 >/dev/tty1 2>&1') # Start getty process on configured serial interfaces for device in console['device']: # Only start console if it exists on the running system. If a user # detaches a USB serial console and reboots - it should not fail! if os.path.exists(f'/dev/{device}'): call(f'systemctl restart serial-getty@{device}.service') return None if __name__ == '__main__': try: c = get_config() verify(c) generate(c) apply(c) except ConfigError as e: print(e) exit(1)