xc

[mouse () Collatz McRCIM McGill EDU (der Mouse)]

I (quoted and) wrote:

> > host vs. user based authentication as it relates to the X server.
> Um, I thought there was no user-based authentication, only host-based
> or magic-value-based.

At least two people have (politely, even) pointed out that I'm behind
the times in saying that.  Sorry about spouting ignorant
misinformation, people.

I also (quoted and) wrote:

> > So is there anything I can do?
> [U]se a front-end a la xc and let it do the authentication; this has
> the advantage that it can also monitor.

I've received notes from two people already asking what xc is and where
it can be obtained, so I thought I'd drop a note here explaining.

xc is a front-end program I wrote.  It fits into the X paradigm by
sitting between the client and the server; to the server, it appears to
be a client, and to the (real) client, it looks like a server.  You
point all your client programs at the pseudo-display xc has set up, and
when xc receives a connection, it establishes a connection of its own
to the real server and passes X protocol data streams back and forth.

Of course, that's not all it does.  It also maintains a private X
connection, which it uses to display a list of client connections it's
managing; this connection also serves to let the user manipulate those
connections in certain ways - to freeze the connection (which causes xc
to stop passing data streams back and forth) or kill it (which causes
xc to close down its connections to the client and the server).  It
also watches the X protocol flowing past, and when it sees the client
trying to take certain actions it doesn't like, it temporarily freezes
the connection and pops up an alert.  (This "managerial" connection is
normally, but not necessarily, to the same display connections get
forwarded to.)

It's fairly rudimentary at present; it badly needs better checks, more
user interaction, and most of all, some sort of configuration better
than editing the source and recompiling.  Someday I'll probably get
around to doing some of those.

It's available by anonymous ftp from collatz.mcrcim.mcgill.edu
(132.206.78.1); cd /X and fetch xc.c, xc.doc, and/or xc.inst.  (Ask for
.gz versions if you have gunzip, please; be kind to my poor slow
netlink....)  The name is admittedly somewhat unfortunate, in view of
the Consortium's naming one of their high-level directories xc.  I may
rename it at some point.

                                        der Mouse

                            mouse () collatz mcrcim mcgill edu