[Libssh] X11 forwarding and Forward listening

[Keisial]

Vic Lee wrote:
> Hi guys,
>
> First of all thanks for this great project!
>
> Acually I am using almost all SSH client features (port forwarding,
> shell, sftp) in my project (grdc) so I really appreciate it.
>
> Recently I am seeking the possibility to use X11 forwarding. This is
> the the feature in openssh -X option.
>
> Another feature is forward listening: ask the SSH server to listen on
> a port, and if a connection is made, create a tunnel to the SSH client.
>
> And I think X11 forwarding can be implemented through forward
> listening (by asking the SSH server to listen on a dummy x11 display
> and tunnel back to the local X server) but I need some more time to
> look at the openssh source code to understand exactly how it works.

AFAIK X11 forwarding is just port forwarding the udp port or file
socket, plus adding the dummy DISPLAY env var.