DTLS transport

[reklatsmasters]

I think libp2p may implement dtls transport. I'm author of pure js dtls transport - https://github.com/nodertc/dtls. Right now it's only client side version with modern secure ciphers (AEAD, ECDHE).

Go and rust implementations may use GnuTLS or OpenSSL.

[backkem]

@reklatsmasters We've just finished our initial DTLS implementation at pions/dtls. Maybe we can collaborate on JS and Go DTLS transport? And maybe we can do the webrtc ones afterwards ;)

cc @Sean-Der

[backkem]

Progress:

• I created a PR for a dlts multiaddr at Add dtls multiaddr multiformats/multiaddr#76
• I created a PR for the dlts go-multiaddr implementation at add dtls multiaddr multiformats/go-multiaddr#86

Some open points:

• There is currently no implementation of libp2p/js-libp2p-udp and libp2p/go-udp-transport.
• This seems due to the missing packet based transport spec: WIP: Add PacketTransport go-libp2p-transport#19
• The Listen method seems a bit weird in our context since I don't think we can mux DTLS connections over one UDP connection. To investigate what other implementations are doing...

[backkem]

Regarding the open points above: These seem to resolve themselves if we assume the DTLS transport also manages it's own UDP sockets.

[backkem]

Go POC at: backkem/go-libp2p-dtls-transport