I am trying to get example 2 on this page: http://www.squidguard.org/Doc/examples.html working thru the IPFire interface, with the addition that the rule is applied only during a time constraint period. In English: I want a "whitelist-only" access policy within a time contraint.
It's easy to get the desired policy working as the default (simply check "Block all URLs not explicitly allowed:" under Advanced Settings on the "url filter settings" page), but this makes the whitelist-only config permanent, i.e., regardless of time contraints.
The closest I've gotten is using "blocked expressions", and putting in an expression that catches anything that might go into the URL line. But the resultant behavior is unacceptable: instead of getting the default "Access Denied" page almost instantly, the page just spins until finally it times out and I get an error from the browser (i.e., NOT from the IPFire server) that it can't load the page.
I have also tried writing directly to the squidGuard.conf file, but that gets overwritten every time I save my settings thru the IPFire web interface.