[H-GEN] squid and facebook

[Troy Piggins]

I've got a squid server as a transparent proxy redirecting port 80
to 3128, and during work hours blocking certain websites that are
definitely not work-related.  Obviously facebook is on the list.
Set up as an acl url_regex pointing to a text file, and the facebook
entry is:

.facebook.com

This and the other blocked sites works as intended, blocked during
work hours but allowed outside of work hours.  We're pretty flexible
here.

But what I've noticed is that if the client has the firefox addon
for facebook, it gets through.  The URL in the browser window is
something like http://www.facebook.com/?home and the above regex
should block that.  It certainly does if block it if the addon is
disabled or removed.

The only things I can think of are that this FF addon somehow falls
back to some port other than 80 if it doesn't get through on that,
or, even though the browser URL is displaying the above the content
is actually coming from somewhere else?  Checking the sarg logs
I see FB's content server domain fbcdn.net and have blocked that
too but no joy.

Any ideas?  I could block all outgoing ports other than the few
servers, but in the past I've found that's painful.

-- 
Troy Piggins