I am getting the impression that I would have to have my linux box acting as
the firewall. At the moment I operate my entire network behind a hardware
filewall. Short of blocking all of the ports for my client PCs, it looks as
if there is no way of blocking these sites.
I tried using snort, but it looks as if all of the traffic goes directly
from the internet to the client machine, through the hardware firewall.
Here is a sketch of how my network operates.
+----------- Linux box /
squid server
H'WARE |
INTERNET -----> FIREWALL +----------- Client PC
|
+----------- Client PC
