EdgeRouter PPTP/L2TP Firewall Modify

AUTO_VPN 是我的规则名称
/config/scripts/post-config.d/auto_vpn_fw_modify 需要加执行权限

EdgeRouter PPTP/L2TP Firewall Modify by @sskaje: https://sskaje.me/2017/02/edgerouter-pptpl2tp-firewall-modify/