MUX: Prevent goroutine leak

[patterniha]

fix problems:

1. after using DispatchLink, we may have goroutine-leak when connection between mux-client and mux-server cut.

2. in some cases in mux dispatchLink wait on wrong things and it cause code-stuck and goroutine leak.

3. for reverse, we may have goroutine-leak when a sub-client-connection cut

///

4. most NAT TCP translations time out is 24 hours, so change splice-timeout to 24 hours.

[Fangliding]

你真的可以在旧版本触发出来这些bug吗

[patterniha]

你真的可以在旧版本触发出来这些bug吗

this bugs appear after using DispatcherLink, for example if connection between mux-client and mux-server cut(with no fin-ack), the code stuck in:

Xray-core/common/mux/server.go

Line 294 in ab1fa13

err := meta.Unmarshal(reader)

so we should implement "monitor" for mux-server too(when we have no session and server-mux is idle for a 60 seconds, ServerWorker should be closed, it is safe because client-mux closes after 16-seconds idle-time)

///

or on the client-side, "DispatcherLink" waited on fetchInput and as a result waited on:

Xray-core/common/mux/client.go

Line 278 in ab1fa13

if err := buf.Copy(s.input, writer); err != nil {

but if sub-client-inbound-connection cut(with no fin-ack), the code stuck here, because now s.input is not pipe-reader and common.Interrupt(s.input) has no effect, so we should implement done.Instance for Session and DispatcherLink should wait on it.

[RPRX]

没有破坏 XUDP UoT Migration 吧

[patterniha]

It has nothing to do with XUDP, just added "monitor" for mux-server-side.
also dispatcherLink should not wait on inbound-reader, because inbound-reader may ends only after dispatcherLink ends, and this cause stuck.(when no fin-ack received)

[patterniha]

checked again and ready.

[patterniha]

rebased.