[pfSense Support] denial of service attack

[Jeremy Rempel]

I work for a school division and our portal is being hosted behind a pfsense box.  Over the holiday weekend we were bombarded by a denial of service attack from all over the world, mostly asia and russia.  To get our portal up and reliable again, I blocked access to most of Asia, Russia, and other networks that were agressively attacking our site.  Is there a feature or add-on module that can recognize and protect our site from aggressive attacks?

Thanks,
Jeremy