Tornado—An Automatic Source Code Obfuscator

ATCorp developed a prototype implementation of Tornado, a suite of automatic obfuscation transformation tools, and demonstrated that obfuscation cost could be accurately predicted and could be used to drive automatic obfuscation. Obfuscation's effectiveness depends intimately on the capabilities of the adversary as well as the nature of the information that must be concealed from the adversary. ATCorp developed mechanisms to quantify obfuscation's effectiveness in order to use it to drive obfuscation selection. A software obfuscation framework was developed.

The Tornado effort focused on developing source-code modifications. A number of source-level obfuscations were developed, evaluated, and can not be employed by a software protect specialist. The process involves first converting programs into CIL (a C Intermediate Language) and then manipulating the CIL code to provide software protection. The protected CIL code is then exported as C.