stund
=====

A minimal asynchronous STUN server implementation.

The server implements the minimal necessary functionality from
[RFC 8489](https://datatracker.ietf.org/doc/html/rfc8489), namely
the Binding Request.

The server is both IPv6 and IPv4 capable as well as operating in both TCP/UDP modes.
When listening on IPv6 address, the server is capable of handling IPv6/IPv4 clients.

Running
-------

To try out the server, just run:

```shell
$ cargo run
```

By default, the server will receive requests from any network hosts using IPv6,
this can be adjusted by adding a `--no-ipv4` option to disable IPv6 or manually
specifying the `host:port` pair to listen on:

```shell
$ cargo run -- 127.0.0.1:3478
```

Testing
-------

To verify the server functions properly, the following tools may be used:

* [Trickle ICE tester from WebRTC github samples](https://webrtc.github.io/samples/src/content/peerconnection/trickle-ice/)
* [IceTest.Info](https://icetest.info/)
* `stunclient` package from [stunprotocol.org](stunprotocol.org).
*Note: the server will report an error due to stunclient sending additional attributes not
recognized by this implementation*

Testings results are also recorded as Wireshark captures and are found in [pcaps](this directory).