header filter !

Hi,

Try using Trendmicro Web Security Suite. It block users from accessing illegal sites.

snipped-for-privacy@w-manager.com

Hi all I work in a company , they want a packet filter system for their gateway their users may want to set proxy ( every proxy servers are open ) I am looking for a firewall software that listens for all packets , if the (http header request ) coniants ( for example sex , violance ... ) then forward it to our proxy server and my proxy server simply block it .

for example one user may set anonymouse proxy in his browser , but when he wants to see illegal sites , firewall forward his request to my proxy server !

what do you suggest ? thanks

Kind Regards SAber Khamooshi

Hello Saber

I suggest using iptables as a firewall / router.

You can configure iptables to forward all HTTP requests to a proxy.

This article may help configuration :

Maxime Ducharme Programmeur / Spécialiste en sécurité réseau

is there any opensource sulotion ? like iptables , ipfw and ... ?

thanks

Kind Regards SAber Khamooshi

hmmmm ok, I think this would be hard to manage

a "free proxy" can be setup on any TCP port, some of them are more standard but thats all

I suggest you use iptables as a gateway, and allow only *some* outbound ports to be used (like 21, 80, 110, 443, ...).

This eradicates most of "free proxy". If a user setup his own proxy on port 21 at home, this is different problem, you need a stateful packet inspection module that would analyser if traffic on port 21 is really FTP and not HTTP.

The 1rst solution would get rid of most of normal users (but not skilled users), it then depends on your organisation AUP.

HTH

Maxime Ducharme Programmeur / Spécialiste en sécurité réseau

Hi Maxime thanks for references I am familiar with squid , but my problem is I don't want redirect all destination traffic ( 8080 , 8000 , 3128 , 81 and .... ) to my squid statically. I want iptables listens for all packets and then if their destination service is ( http ) simply redirect to squid maybe one user sets W.X.Y.Z:1111 as a free Proxy server but when he wants to connect to this proxy server , iptables forward his traffic to squid .

Kind Regards SAber Khamooshi

Hi maxime I exactly need a "stateful packet inspection" does iptables support this ? or freebsd ipfw ?

thanks

Kind Regards SAber Khamooshi

Hi again

No iptables do not support this directly, some work have been done to do this here :

I do not know BSD enough to tell you if it can do this, maybe someone else can answer this ?

HTH

Maxime Ducharme Programmeur / Spécialiste en sécurité réseau