I have a iptables firewall version 1.2.5, I LOVE IPTABLES SO MUCH MORE THINGS YOU CAN DO. I have a small network off my eth0 interface 192.168.0.X network and my ppp0 is my DSL connection, with the current firewall how would I block someone going to the Internet from my eth0 interface. I have tried many of things here and had no luck. Both my INPUT and OUTPUT used a DROP policy by default and I am using NAT to route my traffic to the Internet. echo "1" > /proc/sys/net/ipv4/ip_dynaddr echo 2 > /proc/sys/net/ipv4/conf/all/rp_filter echo 1 > /proc/sys/net/ipv4/icmp_echo_ignore_broadcasts echo 0 > /proc/sys/net/ipv4/conf/all/accept_source_route echo 0 > /proc/sys/net/ipv4/tcp_timestamps echo 1 > /proc/sys/net/ipv4/tcp_syncookies echo 0 > /proc/sys/net/ipv4/conf/all/accept_redirects echo 1 > /proc/sys/net/ipv4/icmp_ignore_bogus_error_responses echo 1 > /proc/sys/net/ipv4/conf/all/log_martians echo "32768 61000" > /proc/sys/net/ipv4/ip_local_port_range echo 30 > /proc/sys/net/ipv4/tcp_fin_timeout echo 2400 > /proc/sys/net/ipv4/tcp_keepalive_time echo 0 > /proc/sys/net/ipv4/tcp_window_scaling echo 0 > /proc/sys/net/ipv4/tcp_sack modprobe ip_conntrack modprobe ip_tables modprobe iptable_filter modprobe iptable_mangle modprobe iptable_nat modprobe ipt_LOG modprobe ipt_REJECT modprobe ipt_MASQUERADE modprobe ip_conntrack_ftp modprobe ipt_owner modprobe ip_conntrack_irc echo 1 > /proc/sys/net/ipv4/ip_forward iptables -t nat -A POSTROUTING -o ppp0 -j MASQUERADE iptables -A FORWARD -j ACCEPT iptables -A INPUT -i eth0 -j ACCEPT iptables -A INPUT -i lo -s 127.0.0.0/8 -d 127.0.0.0/8 -j ACCEPT iptables -A INPUT -i ppp0 -p udp --dport 1024: -j ACCEPT iptables -A INPUT -i ppp0 -p udp --sport 67 --dport 68 -j ACCEPT iptables -A INPUT -i ppp0 -p udp -s 208.188.197.4 --sport 53 --dport 1024:65535 -j ACCEPT iptables -A INPUT -i ppp0 -p udp -s 206.148.122.8 --sport 53 --dport 1024:65535 -j ACCEPT iptables -A INPUT -i ppp0 -p udp -s 206.148.122.2 --sport 53 --dport 1024:65535 -j ACCEPT iptables -A INPUT -i ppp0 -p tcp ! --syn -j ACCEPT iptables -A INPUT -i ppp0 -p icmp -j DROP iptables -P INPUT DROP iptables -A OUTPUT -d 192.168.0.0/24 -j ACCEPT iptables -A OUTPUT -d 255.255.255.255 -j ACCEPT iptables -A OUTPUT -d 127.0.0.1 -j ACCEPT iptables -P OUTPUT DROP
