#!/bin/bash
IPT="/sbin/iptables"

echo "Starting IPv4 Wall..."
$IPT -F
$IPT -X
$IPT -t nat -F
$IPT -t nat -X
$IPT -t mangle -F
$IPT -t mangle -X
modprobe ip_conntrack
modprobe ip_conntrack_ftp
modprobe nf_conntrack_ftp

BADIPS=$(egrep -v -E "^#|^$" /root/scripts/blocked.fw)
PUB_IF="eth0"
SSH_PORT="22"

#unlimited
$IPT -A INPUT -i lo -j ACCEPT
$IPT -A OUTPUT -o lo -j ACCEPT

# DROP all inc
$IPT -P INPUT DROP
$IPT -P OUTPUT DROP
$IPT -P FORWARD DROP

# block all bad ip
for ip in $BADIPS
do
    $IPT -A INPUT -s $ip -j DROP
    $IPT -A OUTPUT -d $ip -j DROP
done

# sync
$IPT -A INPUT -i ${PUB_IF} -p tcp ! --syn -m state --state NEW  -m limit --limit 5/m --limit-burst 7 -j LOG --log-level 4 --log-prefix "Drop Syn"

$IPT -A INPUT -i ${PUB_IF} -p tcp ! --syn -m state --state NEW -j DROP

# Fragments
$IPT -A INPUT -i ${PUB_IF} -f  -m limit --limit 5/m --limit-burst 7 -j LOG --log-level 4 --log-prefix "Fragments Packets"
$IPT -A INPUT -i ${PUB_IF} -f -j DROP

# bad stuff
$IPT  -A INPUT -i ${PUB_IF} -p tcp --tcp-flags ALL FIN,URG,PSH -j DROP
$IPT  -A INPUT -i ${PUB_IF} -p tcp --tcp-flags ALL ALL -j DROP

$IPT  -A INPUT -i ${PUB_IF} -p tcp --tcp-flags ALL NONE -m limit --limit 5/m --limit-burst 7 -j LOG --log-level 4 --log-prefix "NULL Packets"
$IPT  -A INPUT -i ${PUB_IF} -p tcp --tcp-flags ALL NONE -j DROP # NULL packets

$IPT  -A INPUT -i ${PUB_IF} -p tcp --tcp-flags SYN,RST SYN,RST -j DROP

$IPT  -A INPUT -i ${PUB_IF} -p tcp --tcp-flags SYN,FIN SYN,FIN -m limit --limit 5/m --limit-burst 7 -j LOG --log-level 4 --log-prefix "XMAS Packets"
$IPT  -A INPUT -i ${PUB_IF} -p tcp --tcp-flags SYN,FIN SYN,FIN -j DROP #XMAS

$IPT  -A INPUT -i ${PUB_IF} -p tcp --tcp-flags FIN,ACK FIN -m limit --limit 5/m --limit-burst 7 -j LOG --log-level 4 --log-prefix "Fin Packets Scan"
$IPT  -A INPUT -i ${PUB_IF} -p tcp --tcp-flags FIN,ACK FIN -j DROP # FIN packet scans

$IPT  -A INPUT -i ${PUB_IF} -p tcp --tcp-flags ALL SYN,RST,ACK,FIN,URG -j DROP

# full outgoing connection
$IPT -A INPUT -i ${PUB_IF} -m state --state ESTABLISHED,RELATED -j ACCEPT
$IPT -A OUTPUT -o ${PUB_IF} -m state --state NEW,ESTABLISHED,RELATED -j ACCEPT

# ssh
$IPT -A INPUT -i ${PUB_IF} -p tcp --dport ${ssh_port} -j ACCEPT
$IPT -A OUTPUT -i ${PUB_IF} -p tcp --sport ${ssh_port} -j ACCEPT
$IPT -I INPUT -i ${PUB_IF} -p tcp --dport ${ssh_port} -m state --state NEW -m recent  --set
$IPT -I INPUT -i ${PUB_IF} -p tcp --dport ${ssh_port} -m state --state NEW -m recent  --update --seconds 60 --hitcount 5 -j DROP

# http
$IPT -A INPUT -i ${PUB_IF} -p tcp --destination-port 80 -j ACCEPT
$IPT -A OUTPUT -i ${PUB_IF} -p tcp --sport 80 -j ACCEPT

#dns
$IPT -A OUTPUT -i ${PUB_IF} -p udp –dport 53 -j ACCEPT

# ping pong stuff
$IPT -A INPUT -i ${PUB_IF} -p icmp --icmp-type 8 -m state --state NEW,ESTABLISHED,RELATED -j ACCEPT
$IPT -A OUTPUT -i ${PUB_IF} -p icmp --icmp-type 0 -m state --state ESTABLISHED,RELATED -j ACCEPT

#NTP
$IPT -A OUTPUT -i ${PUB_IF} -p udp –dport 123 -j ACCEPT
$IPT -A INPUT -i ${PUB_IF} -p udp –dport 123 -j ACCEPT

# smb/windows
$IPT -A INPUT -p tcp -i ${PUB_IF} --dport 137:139 -j REJECT
$IPT -A INPUT -p udp -i ${PUB_IF} --dport 137:139 -j REJECT

# Log
$IPT -A INPUT -j LOG
$IPT -A FORWARD -j LOG
$IPT -A INPUT -j DROP

# Start ipv6 firewall
#echo "Starting IPv6 Wall..."
#/root/scripts/start6.fw

exit 0