Re: X11 Forwarding

[Dustin Oprea <myselfasunder@xxxxxxxxx>]

Does that mean that the request_x11() and/or accept_x11() no longer need to
be called?

What am I doing inside the callback.. Just do ssh_channel_new(), or do I do
an accept_x11() and return the ssh_channel from that?

I always appreciate your help, Aris.


On Thu, Sep 12, 2013 at 1:36 PM, Aris Adamantiadis <aris@xxxxxxxxxxxx>wrote:

> Hi Dustin,
>
> ssh_channel_accept_x11() is called shortly after request_x11 when you
> know that you're going to receive an X11 socket. However since 0.6rc
> there's a session-defined callback to handle new X11 connections:
>
> /**
>  * @brief Handles an SSH new channel open X11 request. This happens when
> the server
>  * sends back an X11 connection attempt. This is a client-side API
>  * @param session current session handler
>  * @param userdata Userdata to be passed to the callback function.
>  * @returns a valid ssh_channel handle if the request is to be allowed
>  * @returns NULL if the request should not be allowed
>  * @warning The channel pointer returned by this callback must be closed
> by the application.
>  */
> typedef ssh_channel (*ssh_channel_open_request_x11_callback)
> (ssh_session session,
>       const char * originator_address, int originator_port, void
> *userdata);
>
> struct ssh_callbacks_struct {
> /* ... */
>   /** This function will be called when an incoming X11 request is
> received.
>    */
>   ssh_channel_open_request_x11_callback channel_open_request_x11_function;
> };
>
> I tested this in an application for a client but unfortunately don't
> have any example around. However it's pretty simple if you look at the
> other callback-based examples (like proxy.c or samplesshd-cb.c)
>
> Kr,
>
> Aris
>
> Le 12/09/13 12:58, Dustin Oprea a écrit :
> > Does someone have experience with X11 forwarding? I'm current fixing
> > another anomaly, but I wanted to get my thoughts straight on this. This
> > is the theoretical process as it makes sense to me:
> >
> > 1) ssh_channel_accept_x11(). Is this done between reads on the client,
> > on a separate thread,.. or where?
> > 2) At this point, we should have a X11 channel, returned from the accept
> > call.
> > 3) ssh_channel_request_pty()
> > 4) ssh_channel_change_pty_size()
> > 5) ssh_channel_request_x11()
> > 6) ssh_channel_request_shell()
> >
> > What now? Loop over communication on the shell channel -as well as- the
> > X11 channel?
> >
> > Are there any unnecessary steps, above (like the pty_size() call)?
> >
> >
> > Thanks. This is just about the only principal function that isn't
> > clearly covered by the tutorials.
> >
> > Dustin
> >
>
>
>