I'm not an expert on this or anything, but:
Generally, what you'll want to do is configure the system to
start an X server on boot which immediately logs in and only has
a browser running. You could do this with a display manager
such as xdm, kdm or gdm, and a proper .xsession.
As far as blocking outbound traffic from the browser, you could
use netfilter. Perhaps blocking all traffic except for ssh for
This looks like it might be useful:
Hope this helps!
Eric Enright /"\
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