Userspace Networking Stack + WireGuard + Go

[Jason A. Donenfeld]

Another example, for the curious. This one hosts a web server entirely in
userspace. All the kernel sees are incoming and outgoing encrypted
WireGuard UDP packets.

    package main
    import (
        "io"
        "log"
        "net"
        "net/http"
        "golang.zx2c4.com/wireguard/device"
        "golang.zx2c4.com/wireguard/tun"
    )
    func main() {
        tun, tnet, err := tun.CreateNetTUN(
            []net.IP{net.ParseIP("192.168.4.29")},
            []net.IP{net.ParseIP("8.8.8.8"), net.ParseIP("8.8.4.4")},
            1420,
        )
        if err != nil {
            log.Panic(err)
        }
        dev := device.NewDevice(tun, &device.Logger{log.Default(), log.Default(), log.Default()})
        dev.IpcSet(`private_key=a8dac1d8a70a751f0f699fb14ba1cff7b79cf4fbd8f09f44c6e6a90d0369604f
    public_key=25123c5dcd3328ff645e4f2a3fce0d754400d3887a0cb7c56f0267e20fbf3c5b
    endpoint=163.172.161.0:12912
    allowed_ip=0.0.0.0/0
    persistent_keepalive_interval=25
    `)
        dev.Up()
        listener, err := tnet.ListenTCP(&net.TCPAddr{Port: 80})
        if err != nil {
            log.Panicln(err)
        }
        http.HandleFunc("/", func(writer http.ResponseWriter, request *http.Request) {
            log.Printf("> %s - %s - %s", request.RemoteAddr, request.URL.String(), request.UserAgent())
            io.WriteString(writer, "Hello from userspace TCP!")
        })
        err = http.Serve(listener, nil)
        if err != nil {
            log.Panicln(err)
        }
    }

Here's a gif: https://data.zx2c4.com/wireguard-go-userspace-networking-to-host-a-server.gif