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New Firewall Script Required

Hey guys,

Ive used the same firewall script for about a year now.

The firewall script is very basic.
Eth0 LAN
Eth1 Web

The problem is, now I understand what the firewall does its come to my attention that it doesnt block any ports unless i tell it to.

I am looking for a script that denys all, and then opens specific ports

Is there any examples anywhere as i cant seem find any myself and i would trust a firewall i attempted to write myself

Cheers

Smurf :D

i'm using this one, don't know if it's safe or not, if you have to eth devices you should add something, anyway... here it is:

Code:

iptables -F

iptables -F -t mangle

iptables -F -t nat

iptables -X



iptables -P INPUT DROP

iptables -P FORWARD DROP



iptables -A INPUT -m state --state INVALID -j DROP

iptables -A FORWARD -m state --state INVALID -j DROP

iptables -A INPUT -m state --state RELATED,ESTABLISHED -j ACCEPT

iptables -A FORWARD -m state --state RELATED,ESTABLISHED -j ACCEPT



iptables -A INPUT -i lo -m state --state NEW -j ACCEPT



for f in /proc/sys/net/ipv4/conf/*/rp_filter

do

echo 1 > $f

done

It SHOULD block every connection attempt started from the net, and allow only connections started by you..
hope it helps... cya