1 unstable release

0.3.15 Dec 17, 2023
0.3.14 Dec 17, 2023
0.3.8 Nov 23, 2023

#18 in #tun

46 downloads per month

MIT/Apache

6MB
122K SLoC

C 111K SLoC // 0.3% comments C# 7K SLoC // 0.2% comments Visual Studio Project 2.5K SLoC Rust 1K SLoC // 0.0% comments .NET Resource 358 SLoC // 0.3% comments Visual Studio Solution 232 SLoC Shell 108 SLoC // 0.2% comments Batch 23 SLoC

lwip - A Rust wrapper for lwIP

Version Documentation Download

A netstack for the special purpose of turning packets from/to a TUN interface into TCP streams and UDP packets. It uses lwIP as the backend netstack.

use futures::{SinkExt, StreamExt};

let (stack, mut tcp_listener, udp_socket) = ::lwip::NetStack::new().unwrap();
let (mut stack_sink, mut stack_stream) = stack.split();

// tun device is assumed implementing `Stream` and `Sink`
let (mut tun_sink, mut tun_stream) = tun.split();

// Reads packet from stack and sends to TUN.
tokio::spawn(async move {
    while let Some(pkt) = stack_stream.next().await {
        if let Ok(pkt) = pkt {
            tun_sink.send(pkt).await.unwrap();
        }
    }
});

// Reads packet from TUN and sends to stack.
tokio::spawn(async move {
    while let Some(pkt) = tun_stream.next().await {
        if let Ok(pkt) = pkt {
            stack_sink.send(pkt).await.unwrap();
        }
    }
});

// Extracts TCP connections from stack and sends them to the dispatcher.
tokio::spawn(async move {
    while let Some((stream, local_addr, remote_addr)) = tcp_listener.next().await {
        tokio::spawn(handle_inbound_stream(stream, local_addr, remote_addr));
    }
});

// Receive and send UDP packets between netstack and NAT manager. The NAT
// manager would maintain UDP sessions and send them to the dispatcher.
tokio::spawn(async move {
    handle_inbound_datagram(udp_socket).await;
});

Dependencies

~3–14MB
~173K SLoC