#!/bin/sh

if [ "${FIREZONE_ENABLE_MASQUERADE}" = "1" ]; then
    IFACE="tun-firezone"
    # Enable masquerading for ethernet and wireless interfaces
    iptables -C FORWARD -i $IFACE -j ACCEPT >/dev/null 2>&1 || iptables -A FORWARD -i $IFACE -j ACCEPT
    iptables -C FORWARD -o $IFACE -j ACCEPT >/dev/null 2>&1 || iptables -A FORWARD -o $IFACE -j ACCEPT
    iptables -t nat -C POSTROUTING -o e+ -j MASQUERADE >/dev/null 2>&1 || iptables -t nat -A POSTROUTING -o e+ -j MASQUERADE
    iptables -t nat -C POSTROUTING -o w+ -j MASQUERADE >/dev/null 2>&1 || iptables -t nat -A POSTROUTING -o w+ -j MASQUERADE
    ip6tables -C FORWARD -i $IFACE -j ACCEPT >/dev/null 2>&1 || ip6tables -A FORWARD -i $IFACE -j ACCEPT
    ip6tables -C FORWARD -o $IFACE -j ACCEPT >/dev/null 2>&1 || ip6tables -A FORWARD -o $IFACE -j ACCEPT
    ip6tables -t nat -C POSTROUTING -o e+ -j MASQUERADE >/dev/null 2>&1 || ip6tables -t nat -A POSTROUTING -o e+ -j MASQUERADE
    ip6tables -t nat -C POSTROUTING -o w+ -j MASQUERADE >/dev/null 2>&1 || ip6tables -t nat -A POSTROUTING -o w+ -j MASQUERADE
fi

if [ "${LISTEN_ADDRESS_DISCOVERY_METHOD}" = "gce_metadata" ]; then
    echo "Using GCE metadata to discover listen address"

    if [ "${PUBLIC_IP4_ADDR}" = "" ]; then
        public_ip4=$(curl "http://metadata.google.internal/computeMetadata/v1/instance/network-interfaces/0/access-configs/0/external-ip" -H "Metadata-Flavor: Google" -s)
        export PUBLIC_IP4_ADDR="${public_ip4}"
        echo "Discovered PUBLIC_IP4_ADDR: ${PUBLIC_IP4_ADDR}"
    fi

    if [ "${PUBLIC_IP6_ADDR}" = "" ]; then
        public_ip6=$(curl "http://metadata.google.internal/computeMetadata/v1/instance/network-interfaces/0/ipv6s" -H "Metadata-Flavor: Google" -s)
        export PUBLIC_IP6_ADDR="${public_ip6}"
        echo "Discovered PUBLIC_IP6_ADDR: ${PUBLIC_IP6_ADDR}"
    fi
fi

exec "$@"