#!/bin/sh

SYSTEM=`uname`;

if [ "$SYSTEM" = "Linux" ]; then
    if ! grep "ogstun" /proc/net/dev > /dev/null; then
        ip tuntap add name ogstun mode tun
    fi
	if test "x`sysctl -n net.ipv6.conf.ogstun.disable_ipv6`" = x1; then
		echo "net.ipv6.conf.ogstun.disable_ipv6=0" > /etc/sysctl.d/30-open5gs.conf
		sysctl -p /etc/sysctl.d/30-open5gs.conf
	fi
    ip addr del 10.45.0.1/16 dev ogstun 2> /dev/null
    ip addr add 10.45.0.1/16 dev ogstun
    ip addr del cafe::1/64 dev ogstun 2> /dev/null
    ip addr add cafe::1/64 dev ogstun
    ip link set ogstun up
else
    sysctl -w net.inet.ip.forwarding=1
    ifconfig lo0 alias 127.0.0.2 netmask 255.255.255.255
    ifconfig lo0 alias 127.0.0.3 netmask 255.255.255.255
    ifconfig lo0 alias 127.0.0.4 netmask 255.255.255.255
    ifconfig lo0 alias 127.0.0.5 netmask 255.255.255.255
    ifconfig lo0 alias 127.0.0.6 netmask 255.255.255.255
    ifconfig lo0 alias 127.0.0.7 netmask 255.255.255.255
    ifconfig lo0 alias 127.0.0.8 netmask 255.255.255.255
    ifconfig lo0 alias 127.0.0.9 netmask 255.255.255.255
    ifconfig lo0 alias 127.0.0.10 netmask 255.255.255.255
    ifconfig lo0 alias 127.0.0.11 netmask 255.255.255.255
    ifconfig lo0 alias 127.0.0.12 netmask 255.255.255.255
    ifconfig lo0 alias 127.0.0.13 netmask 255.255.255.255
    ifconfig lo0 alias 127.0.0.14 netmask 255.255.255.255
    ifconfig lo0 alias 127.0.0.15 netmask 255.255.255.255
    ifconfig lo0 alias 127.0.0.16 netmask 255.255.255.255
    ifconfig lo0 alias 127.0.0.17 netmask 255.255.255.255
    ifconfig lo0 alias 127.0.0.18 netmask 255.255.255.255
    ifconfig lo0 alias 127.0.0.19 netmask 255.255.255.255
    ifconfig lo0 alias 127.0.0.20 netmask 255.255.255.255
    if [ "$SYSTEM" = "Darwin" ]; then
        if ! test -f /etc/pf.anchors/org.open5gs; then
            sudo sh -c "echo 'nat on {en0} from 10.45.0.0/16 to any -> {en0}' > /etc/pf.anchors/org.open5gs"
        fi
        pfctl -e -f /etc/pf.anchors/org.open5gs
    fi
fi