libnasl -- NASL is a scripting language designed for the Nessus security scanner.
http://www.nessus.org
NASL is a scripting language designed for the Nessus security scanner. Its aim is to allow anyone to write a test for a given security hole in a few minutes, to allow people to share their tests without having to worry about their operating system, and to garantee everyone that a NASL script can not do anything nasty except performing a given security test against a given target.