Call Tree Transformation for Program Obfuscation and Copy Protection

In this paper we propose a new scheme for software obfuscation and license protection that is based on an original transformation of the program’s call tree. The idea is based on the observation of similarities between a program’s call tree and Context Free Grammars. First, this paper proposes a practical technique for applying well studied LALR methodologies to transforming a program’s call tree. Second, we suggest methods of effective binding of the transformed program to the program’s installation site. Finally, we note that the given scheme provides us with a series of difficult to remove unique identifications integrally embedded into the transformed programs that could be used for software watermarking purposes.