Build for OpenWrt

Setup OpenWrt build system

Download OpenWrt SDK of a specific target. Update the package feeds:

./scripts/feeds update -a

# It has similar dependencies as xtables-addon. Install these dependencies by
# preparing for xtables-addons.
./scripts/feeds install xtables-addons

At the SDK root directory:

mkdir -p package/feeds/packages/xtables-wgobfs

Copy Makefile to the newly created directory. Build OpenWrt package with:

make menuconfig  # select Network -> Firewall -> iptables-mod-wgobfs
make package/xtables-wgobfs/compile V=s

The build result is two packages under bin/. They are kmod-ipt-wgobfs_xxx.ipk and iptables-mod-wgobfs_xxx.ipk.