iptables for deny all except SSH and 80/443( webserver )

iptables.sh

# flush all current rules
sudo iptables -F

# allows all loopback (lo0) traffic and drop all traffic to 127/8 that doesn't use lo0
sudo iptables -A INPUT -i lo -j ACCEPT
sudo iptables -A INPUT ! -i lo -d 127.0.0.0/8 -j REJECT

# accepts all established inbound connections
sudo iptables -A INPUT -m state --state ESTABLISHED,RELATED -j ACCEPT

# allows all outbound traffic
sudo iptables -A OUTPUT -j ACCEPT

# allows HTTP and HTTPS from anywhere
sudo iptables -A INPUT -p tcp --dport 80 -j ACCEPT
sudo iptables -A INPUT -p tcp --dport 443 -j ACCEPT

# allows SSH connections, sugest you change your default SSH port in /etc/sshd_config
sudo iptables -A INPUT -p tcp -m state --state NEW --dport 22 -j ACCEPT

# allow ping
sudo iptables -A INPUT -p icmp -m icmp --icmp-type 8 -j ACCEPT

# reject everything else
sudo iptables -A INPUT -j REJECT
sudo iptables -A FORWARD -j REJECT

# log all denied packets(connections)
sudo iptables -A INPUT -m limit --limit 5/min -j LOG --log-prefix "iptables denied: " --log-level 7

# save for use with iptables-persistent package
sudo iptables-save | sudo tee /etc/iptables/rules.v4