How to block web pages without squid

[jopeme]

How can I block web pages (porn, violence, etc.) after a user authenticates against the captive portal ?.
I have squid+squidguard running in non-transparent mode for my other interfaces , but I can not use it for the captive portal since it does not go through the captive portal.
In transparent mode for interface wifi (ethernet board connect to AP) doesn't filter content.

Thanks.

[The Computer Guy]

How about blocking at the DNS level? Lots available out there that'll block categories etc. It's what I do, I also force all DNS (Port 53) traffic through a rule (Plenty of info in these forums) so even if someone sets their own DNS, it's re-routed through the servers I set.

[jopeme]

Actually i force with rules to use pfsense dns on all interfaces. Then what do you want to say when you write "How about blocking at the dns level ?, How i can to do that?

Thanks.

[Gertjan]

Take a look at this look at this : https://forum.pfsense.org/index.php?topic=83155.0
Other thread exists about blocking specific web sites