firewall-ssh-http-openvpn-duosecurity.sh

sudo iptables -F
sudo iptables -A INPUT -p tcp -m state --state ESTABLISHED,RELATED -j ACCEPT
sudo iptables -A INPUT -p udp -m state --state ESTABLISHED,RELATED -j ACCEPT
sudo iptables -I INPUT -i lo -j ACCEPT
sudo iptables -I INPUT -i tun0 -j ACCEPT
sudo iptables -A OUTPUT -o eth0 -p tcp --dport 1194 -m state --state ESTABLISHED -j ACCEPT
sudo iptables -A INPUT -i eth0 -p tcp --dport 80 -m state --state NEW,ESTABLISHED -j ACCEPT
sudo iptables -A OUTPUT -o eth0 -p tcp --sport 80 -m state --state ESTABLISHED -j ACCEPT
sudo iptables -A INPUT -i eth0 -p tcp --dport 443 -m state --state NEW,ESTABLISHED -j ACCEPT
sudo iptables -A OUTPUT -o eth0 -p tcp --sport 443 -m state --state ESTABLISHED -j ACCEPT
sudo iptables -A OUTPUT -o eth0 -p tcp --dport 443 -m state --state NEW,ESTABLISHED -j ACCEPT
sudo iptables -A INPUT -i eth0 -p tcp --sport 443 -m state --state ESTABLISHED -j ACCEPT
sudo iptables -A INPUT -i eth0 -p tcp --dport ssh -m state --state NEW,ESTABLISHED -j ACCEPT
sudo iptables -A OUTPUT -o eth0 -p tcp --sport ssh -m state --state ESTABLISHED -j ACCEPT
sudo iptables -A OUTPUT -p udp --sport 1024:65535 --dport 53 -m state --state NEW,ESTABLISHED -j ACCEPT
sudo iptables -A OUTPUT -p tcp --sport 1024:65535 --dport 53 -m state --state NEW,ESTABLISHED -j ACCEPT
sudo iptables -A INPUT -j DROP
sudo iptables -A OUTPUT -j DROP
sudo iptables -A FORWARD -j DROP
sudo service iptables save