#!/bin/bash

ALLOWED="21 22 80 25565 6379 45700 8087"

iptables -P INPUT ACCEPT
iptables -F
iptables -X
iptables -Z

iptables -A INPUT -i lo -j ACCEPT
iptables -A OUTPUT -o lo -j ACCEPT

for port in $ALLOWED; do
echo "Aceptando el puerto TCP $port..."
iptables -A INPUT -p tcp --dport $port -j ACCEPT
done

for port in $ALLOWED; do
echo "Aceptando el puerto UDP $port..."
iptables -A INPUT -p udp --dport $port -j ACCEPT
done

iptables -A INPUT -m state --state RELATED,ESTABLISHED -j ACCEPT

iptables -A INPUT -p udp -j DROP
iptables -A INPUT -p tcp --syn -j DROP
iptables -N syn_flood
iptables -A INPUT -p tcp --syn -j syn_flood
iptables -A syn_flood -m limit --limit 3/s --limit-burst 9 -j RETURN
iptables -A syn_flood -j DROP
iptables -A INPUT -p icmp -m limit --limit  1/s --limit-burst 1 -j ACCEPT
iptables -A INPUT -p icmp -m limit --limit 1/s --limit-burst 1 -j LOG
iptables -A INPUT -p tcp --syn --dport 25565 -m connlimit --connlimit-above 3 -j REJECT

ufw allow 20
ufw allow 21
ufw allow 22
ufw allow 80
ufw allow 25565
ufw enable