`/dnsaddr` is handled as `/dns4` in `libp2p-websocket` and `libp2p-websocket-websys`

[oblique]

Summary

/dnsaddr is handled as /dns4 in libp2p-websocket and libp2p-websocket-websys. This is incorrect because /dnsaddr is only for quering _dnsaddr.domain from DNS.

/dnsaddr support in WebSocket is tracked in #5529.

libp2p-websocket:

rust-libp2p/transports/websocket/src/framed.rs

Lines 511 to 516 in a2a2816

	(Some(Protocol::Dns(h)), Some(Protocol::Tcp(port)))
	| (Some(Protocol::Dns4(h)), Some(Protocol::Tcp(port)))
	| (Some(Protocol::Dns6(h)), Some(Protocol::Tcp(port)))
	| (Some(Protocol::Dnsaddr(h)), Some(Protocol::Tcp(port))) => {
	break (format!("{h}:{port}"), tls::dns_name_ref(&h)?)
	}

libp2p-websocket-websys:

rust-libp2p/transports/websocket-websys/src/lib.rs

Lines 131 to 136 in a2a2816

	(Some(Protocol::Dns(h)), Some(Protocol::Tcp(port)))
	| (Some(Protocol::Dns4(h)), Some(Protocol::Tcp(port)))
	| (Some(Protocol::Dns6(h)), Some(Protocol::Tcp(port)))
	| (Some(Protocol::Dnsaddr(h)), Some(Protocol::Tcp(port))) => {
	format!("{}:{}", &h, port)
	}

Expected behavior

TransportError::MultiaddrNotSupported should be returned from dial.

Actual behavior

/dnsaddr multiaddress is dialed as if it was /dns4.

Relevant log output

No response

Possible Solution

No response

Version

0.54.1

Would you like to work on fixing this bug ?

Maybe

[dariusc93]

Hey! Interesting find. I would have always assumed that using dnsaddr in this manner for websocket is fine but it does make sense that it would be meant to query the dns record itself.