Implement StreamMuxer trait for Connection

[melekes]

• StreamMuxer trait
• Authenticate peer via Noise (single data channel, which can be reused later; noise can be dropped afterwards)
• Write tests
• stream: allow reading after stream is closed webrtc-rs/sctp#14

[melekes]

@tomaka could you please take a look at this when you have the time? Thanks.

[tomaka]

The multiple mutexes feel a bit dangerous to me, both in terms of deadlock and in terms of race conditions (what if another method is called between the moment a mutex is unlocked and the next one locked? is it ok everywhere?)
I think that a single mutex covering all the fields is much safer and probably not much slower.

[tomaka]

Another point is that I would suggest keeping the single data stream implementation on the side.
I feel like I'm getting ignored, but to me it's a good idea to also give the possibility to have this single data stream system.

[melekes]

I think that a single mutex covering all the fields is much safer and probably not much slower.

This is how it was done before. Unfortunately, I had to switch to multiple mutexes (futures::Mutex and std::Mutex) because I was not able to get both async and sync code to compile with just one (I've tried both futures::Mutex and std::sync::Mutex).

If I use futures::Mutex, it works inside async future, but I had to poll it in sync code and I wasn't sure how it will play with the rest of the code (i.e. if polling future returns ready, but mutex is not ready, will the future returns ready next time it's called?).

If I use std::sync::Mutex, I have problems when locking data across await, I believe.

I can try again though.

[melekes]

Another point is that I would suggest keeping the single data stream implementation on the side. I feel like I'm getting ignored, but to me it's a good idea to also give the possibility to have this single data stream system.

It's still possible to do with the new implementation. You get a Connection and call open_outbound substream. Then you use it to communicate with the other party. Or you can open additional data channels (it's up to you).