kupferbootstrap/forwarding.py

import click
import subprocess
from logger import *


@click.command(name='forwarding')
@verbose_option
def cmd_forwarding(verbose):
    setup_logging(verbose)

    result = subprocess.run(['sysctl', 'net.ipv4.ip_forward=1'])
    if result.returncode != 0:
        logging.fatal(f'Failed to enable ipv4 forward via sysctl')
        exit(1)

    result = subprocess.run(['iptables', '-P', 'FORWARD', 'ACCEPT'])
    if result.returncode != 0:
        logging.fatal(f'Failed set iptables rule')
        exit(1)

    result = subprocess.run(['iptables',
                             '-A', 'POSTROUTING',
                             '-t', 'nat',
                             '-j', 'MASQUERADE',
                             '-s', '172.16.42.0/24'])
    if result.returncode != 0:
        logging.fatal(f'Failed set iptables rule')
        exit(1)

    result = subprocess.run(['ssh',
                             '-o', 'GlobalKnownHostsFile=/dev/null',
                             '-o', 'UserKnownHostsFile=/dev/null',
                             '-o', 'StrictHostKeyChecking=no',
                             '-t', 'kupfer@172.16.42.1',
                             'sudo route add default gw 172.16.42.2'])
    if result.returncode != 0:
        logging.fatal(f'Failed to add gateway over ssh')
        exit(1)