# Deny all SSH connections
iptables -I INPUT -p tcp --dport 22 -j DROP
# All connections from address xyz
iptables -I INPUT -p tcp --source 1.2.3.4 --dport 22 -j ACCEPT
iptables -I INPUT -p tcp --source 5.6.7.8 --dport 22 -j ACCEPT

# Deny all webconfig connections
iptables -I INPUT -p tcp --dport 81 -j DROP
# All connections from address xyz
iptables -I INPUT -p tcp --source 1.2.3.4 --dport 81 -j ACCEPT
iptables -I INPUT -p tcp --source 5.6.7.8 --dport 81 -j ACCEPT