Up-to-date rust implementation of netcode

[Benny Nazimov]

Hi @gafferongames !

I have been working on a new, up-to-date (1.02) rust implementation of the protocol: https://github.com/benny-n/netcode

The existing rust versions by @vvanders' or @jaynus' were really helpful to me, both in practice and as a reference to my own rewrite, but it seems both of them are unmaintained. I plan to maintain and extend this one.

Unlike said versions, this one is not a fork but rather a "from scratch" implementation which to my opinion actually ended up being a bit closer to the original C implementation API-wise (e.g. recv instead of next_event to receive packets, callbacks instead of ServerEvent/ClientEvent, etc.).

Notable changes between this implementation and the others:

• Supports 24-byte random nonces for connection tokens as specified in version 1.02.
• Encryption is implemented with the chacha20poly1305 crate, making this the first rust implementation that does not rely on libsodium, or any FFI at all.
• Better error handling (effectively less unwrap() and more error types)

I can't currently release my version as a crate in crates.io, since it shares a name with @vvanders' version.
I could:

1. Call it netcode2 which avoids the name conflict, but could potentially confuse users(?)
2. Get owner rights to the netcode crate from @vvanders, and push mine as an updated version of the same crate.

Anyway, I would love it if you could include this implementation in your list.

Thanks!

[Glenn Fiedler]

I'm totally down with whatever you want to do. I'm not sure if @vvanders is maintaining the rust version actively, but if he is, or if he can't be contacted, then the netcode2 sounds fine to me. Thanks!