# NAT setup
*nat
:PREROUTING ACCEPT [5:861]
:POSTROUTING ACCEPT [2:156]
:OUTPUT ACCEPT [5:776]
-A POSTROUTING -o ppp0 -j MASQUERADE 
COMMIT

# Mangle setup
*mangle
:PREROUTING ACCEPT [444:43563]
:INPUT ACCEPT [444:43563]
:FORWARD ACCEPT [0:0]
:OUTPUT ACCEPT [402:144198]
:POSTROUTING ACCEPT [402:144198]
-A PREROUTING -p tcp -m tcp --tcp-flags FIN,SYN,RST,PSH,ACK,URG FIN,PSH,URG -j DROP
-A PREROUTING -p tcp -m tcp --tcp-flags FIN,SYN,RST,PSH,ACK,URG NONE -j DROP
-A PREROUTING -p tcp -m tcp --tcp-flags SYN,RST SYN,RST -j DROP
-A PREROUTING -p tcp -m tcp --tcp-flags FIN,SYN FIN,SYN -j DROP
-A PREROUTING -p tcp -m tcp --tcp-flags FIN,SYN,RST,PSH,ACK,URG FIN,PSH,URG -j DROP
-A PREROUTING -p tcp -m tcp --tcp-flags FIN,SYN,RST,PSH,ACK,URG NONE -j DROP
-A PREROUTING -p tcp -m tcp --tcp-flags SYN,RST SYN,RST -j DROP
-A PREROUTING -p tcp -m tcp --tcp-flags FIN,SYN FIN,SYN -j DROP
-A PREROUTING -p tcp -m tcp --tcp-flags FIN,SYN,RST,PSH,ACK,URG FIN,PSH,URG -j DROP
-A PREROUTING -p tcp -m tcp --tcp-flags FIN,SYN,RST,PSH,ACK,URG NONE -j DROP
-A PREROUTING -p tcp -m tcp --tcp-flags SYN,RST SYN,RST -j DROP
-A PREROUTING -p tcp -m tcp --tcp-flags FIN,SYN FIN,SYN -j DROP
-A PREROUTING -p tcp -m tcp --tcp-flags FIN,SYN,RST,PSH,ACK,URG FIN,PSH,URG -j DROP
-A PREROUTING -p tcp -m tcp --tcp-flags FIN,SYN,RST,PSH,ACK,URG NONE -j DROP
-A PREROUTING -p tcp -m tcp --tcp-flags SYN,RST SYN,RST -j DROP
-A PREROUTING -p tcp -m tcp --tcp-flags FIN,SYN FIN,SYN -j DROP
COMMIT

# Filter setup
*filter
:INPUT DROP [1:242]
:FORWARD DROP [0:0]
:OUTPUT DROP [0:0]
:LOG_DROP - [0:0]
:LOG_ACCEPT - [0:0]
:icmp_packets - [0:0]

# Set up inputs

# Allow established, related connections
-A INPUT -m state --state RELATED,ESTABLISHED -j ACCEPT
# Allow ssh
-A INPUT -p tcp -m tcp --dport 22 -j ACCEPT
# Allow ident
-A INPUT -p tcp -m tcp --dport 113 -j ACCEPT
# Allow localhost
-A INPUT -s 127.0.0.1 -j ACCEPT
# Deal with ICMP
-A INPUT -p icmp -j icmp_packets
# Log and drop anything else
-A INPUT -j LOG_DROP

# Now for outputs
-A OUTPUT -m state --state RELATED,ESTABLISHED -j ACCEPT
# Allow outgoing www connections
-A OUTPUT -p tcp -m tcp --dport 80 -j ACCEPT
# Allow outgoing DNS requests
-A OUTPUT -p udp -m udp --dport 53 -j ACCEPT
# Allow localhost
-A OUTPUT -d 127.0.0.1 -j ACCEPT
# Allow all outgoing ICMP
-A OUTPUT -p icmp -j ACCEPT
# Log and drop anything else
-A OUTPUT -j LOG_DROP

# Now log drops
-A LOG_DROP -j LOG --log-prefix "[IPTABLES DROP] " --log-tcp-options --log-ip-options
-A LOG_DROP -j DROP

# Log accept packets, if desired
-A LOG_ACCEPT -j LOG --log-prefix "[IPTABLES ACCEPT] " --log-tcp-options --log-ip-options
-A LOG_ACCEPT -j ACCEPT

# Set up icmp
-A icmp_packets -p icmp -m icmp --icmp-type 0 -j ACCEPT
-A icmp_packets -p icmp -m icmp --icmp-type 8 -j DROP
-A icmp_packets -p icmp -m icmp --icmp-type 3 -j ACCEPT
-A icmp_packets -p icmp -m icmp --icmp-type 11 -j ACCEPT
COMMIT