If I want to use Ubuntu 11.04 as a Firewall in SOHO environment, then I just can't figure out what is the bad thing about installing GUI on it (e.g.: XFCE)?
The only opened port to the world (wan port) would be SSH on a non-default port+pubkey auth only+restricted ip subnets where could people log on, etc..
I'm just not getting the true reasons why does it could affect the "security" of a Firewall if I have GUI on it.
p.s.: "GUI" is just needed because I want to use this machine as a "Movie player/connected to a projector" - that's all. - it would be expensive (power consuption) to use the pc as only a firewall, so I'm using it for playing videos too (not using webbrowser on it).
p.s.2: It would NAT the "internet" through an USB wifi dongle (wpa2/aes/64 char random pass.).
so to clarify:
Why (or HOW Exactly) would an installed XFCE affect the e.g.: SSHD regarding security? (I'm saying that because that's the only server/having open port to the world/wan)