Firewall question

[Linda]

I decided to setup a firewall the easy way with shorewall. The Firewall 
is working well it forwards all the network traffic great and I ran some 
portscans etc and everything behind the firewall is invisible. However I 
have one small problem. The firewall itself can't connect to the 
internet for apt-get. Any suggestions on what I need to allow the 
firewall machine to do updates?
          Thanks
           Linda