#!/bin/bash

set -euo pipefail

mkdir -p /dev/net

if [ ! -c /dev/net/tun ]; then
    echo "Creating /dev/net/tun..."
    mknod /dev/net/tun c 10 200
fi

chmod 600 /dev/net/tun

echo 1 > /proc/sys/net/ipv4/ip_forward

iptables \
    -t nat \
    -C POSTROUTING \
    -s 10.250.250.0/24 \
    -o eth0 \
    -j MASQUERADE \
    2>/dev/null ||
iptables \
    -t nat \
    -A POSTROUTING \
    -s 10.250.250.0/24 \
    -o eth0 \
    -j MASQUERADE

iptables \
    -C FORWARD \
    -i tun0 \
    -o eth0 \
    -j ACCEPT \
    2>/dev/null ||
iptables \
    -A FORWARD \
    -i tun0 \
    -o eth0 \
    -j ACCEPT

iptables \
    -C FORWARD \
    -i eth0 \
    -o tun0 \
    -m conntrack \
    --ctstate RELATED,ESTABLISHED \
    -j ACCEPT \
    2>/dev/null ||
iptables \
    -A FORWARD \
    -i eth0 \
    -o tun0 \
    -m conntrack \
    --ctstate RELATED,ESTABLISHED \
    -j ACCEPT

echo "Starting OpenVPN..."

exec openvpn --config /etc/openvpn/server.conf