iptables -A INPUT -i lo -j ACCEPT
iptables -A INPUT -i eth0 -j ACCEPT
iptables -A INPUT -i eth1 -m state --state ESTABLISHED,RELATED -j ACCEPT
iptables -A INPUT -i eth2 -m state --state ESTABLISHED,RELATED -j ACCEPT
iptables -A INPUT -p tcp -m tcp --dport 21 -j ACCEPT
iptables -A INPUT -p tcp --sport 1024: --dport 1024: -m state --state ESTABLISHED -j ACCEPT
iptables -A OUTPUT -p tcp --sport 1024: --dport 1024: -m state --state ESTABLISHED,RELATED -j ACCEPT

# -- FORWARD --
iptables -A FORWARD -m state --state ESTABLISHED,RELATED - ACCEPT

# -- INCOMING --
iptables -t nat -F PREROUTING
iptables -t nat -A PREROUTING -d 1.2.3.4 -p tcp --dport 21 -j DNAT --to 192.168.1.195
iptables -t nat -A PREROUTING -d 1.2.3.4 -p tcp --dport 1024 -j DNAT --to 192.168.1.195