This is a simple chef recipe to automate the standard lock down steps on a fresh Ubuntu install, these are:

• Install Fail2Ban
• Install UFW (Firewall)
• Install Unattended Upgrades
• Set the system to download updates daily
• set the GB Locale (not security exactly but relevant for SSL stuff)
• Disable SSH Password auth
• Allow SSH traffic through the firewall
• Allow any pre defined traffic through the firewall

This recipe will look for a key firewall_allow in the node definition. If it is defined it will expect it to be an array of hashes in the form:

{ip: an_ip_address, port; a_port}

For each rule, the specified ip address will be granted access to the specified port on the current node.

Root login is left as enabled. It's unclear what the benefit of disabling it is when password auth is disabled.