Utilizzo di UFW come firewall Debian Ubuntu

apt install ufw

• Abilitare il routing:

vi /etc/default/ufw

• Abilitare default policies

...
DEFAULT_FORWARD_POLICY="ACCEPT"
...

• Abilitare routing

vi /etc/ufw/sysctl.conf

net.ipv4.ip_forward=1

Outbound Nat

• Aggiungere la sezione prima di quella filter

vi /etc/ufw/before.rules

# NAT table rules
*nat
:PREROUTING ACCEPT [0:0]
:POSTROUTING ACCEPT [0:0]

# Port Forwardings
#-A PREROUTING -i eth0 -p tcp --dport 22 -j DNAT --to-destination 192.168.1.10

# Nat traffic through eth1 - Change to match you out-interface
-A POSTROUTING -s 10.0.1.0/24 -o eth1 -j MASQUERADE

# don't delete the 'COMMIT' line or these nat table rules won't
# be processed
COMMIT

# Don't delete these required lines, otherwise there will be errors
*filter

Attivazione

sudo ufw disable && sudo ufw enable

Riferimenti

• NAT and FORWARD with Ubuntu’s ufw firewall · GitHub