EFIPW is a tool that can be used to decode and modify Apple EFI firmware passwords via the command line. It is designed after the non open source OFPW utility and is designed to work on Intel machines running Leopard or newer. Useful for lab deployments (setting the firmware password of machines as a post install item) and pen tests (recovering the EFI firmware password).
You can download it from the following link: https://packetstormsecurity.com/files/download/85795/efipw_0.2a.py.txt
Source: https://packetstormsecurity.com/files/85795/EFIPW-Apple-EFI-Firmware-Password-Changer-0.2a.html