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iptables, NAT & Packet Filtering	by DMDx86	2002-06-14 06:47:51
Here are example iptables commands...	by allegory	2002-06-14 07:48:48
This is nearly exactly what I use. I just dropped a few of the bizarre ones that I use for a VPN connection to a corporate network.... #enable forwarding echo "1" >/proc/sys/net/ipv4/ip_forward #flush old rules/chains iptables -F iptables -X #set default policies /sbin/iptables -P INPUT DROP /sbin/iptables -P OUTPUT ACCEPT /sbin/iptables -P FORWARD DROP #accept ssh /sbin/iptables -A INPUT -i eth1 -p tcp --dport ssh -j ACCEPT #accept port 80 #/sbin/iptables -A INPUT -i eth1 -p tcp --dport 80 -j ACCEPT #accept Loopback interface /sbin/iptables -A INPUT -i lo -j ACCEPT #accept everything on eth0 /sbin/iptables -A INPUT -i eth0 -j ACCEPT #Allow all packets that are from an already existing connection. #like your NAT and stuff you started on your end. /sbin/iptables -A INPUT -i eth1 -m state --state ESTABLISHED,RELATED -j ACCEPT /sbin/iptables -A FORWARD -i eth1 -o eth0 -m state --state ESTABLISHED,RELATED -j ACCEPT #accept all packets coming in eth0 destined to go out eth1 /sbin/iptables -A FORWARD -i eth0 -o eth1 -j ACCEPT #drop incoming connection requests. Since you've already enabled those you #want to happen, this drops all others hard... they can't even ping you. /sbin/iptables -A INPUT -i eth1 -p tcp --syn -j DROP #NAT. /sbin/iptables -t nat -A POSTROUTING -o eth1 -j MASQUERADE touch /var/lock/subsys/iptables
[ Reply ]
erm...	by SD Maruko-kun	2002-06-14 11:05:55
thats what I get for writing comments in quickly.. (n/t)	by allegory	2002-06-14 11:30:25

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