moving X11 portforwarding out into a "plugin" framework

[Damien Miller]

On Fri, 22 Jan 2010, Brian J. Murrell wrote:

> I think everyone will admit that X11 forwarding has been an incredible
> feature in [open]ssh. X11 is not the only local->remote protocol that
> might be useful across an SSH session however.
>
> But having to hack the code for new protocols as they come around
> seems silly. Wouldn't it be more useful to be able to describe a
> protocol that needs forwarding and some configuration that might need
> doing on each end outside of the source code?
>
> Then as new applications come along that could take advantage of port
> forward- ing can "plug in" to this system and get their protocols
> forwarded across X without having to hack the openssh code and push it
> upstream, etc.
>
> I would imagine on the local side, the ssh client would need to be
> able to forward into unix and ipv4/6 sockets and on the remote side
> one would need to be able to possibly create sockets and/or set
> environment variables, etc.

You should be able to do most of what you want using a Subsystem (see
sshd_config) and a helper program on the client side.

-d