A Framework for Mobile Phone Java Software Protection

Illegal distribution and use of software is a big ad hoc problem in software industry today, especially on the growing market of mobile software products: the lack of protection may be the most important setback of the expansion of this market. In this paper we present our copy protection scheme targeting primarily mobile phone Java applications, which combines techniques of obfuscation, diversity and tamper-proofing. Instead of obfuscating the program itself , we choose to obfuscate the program interpretation. Each set of permutation rules are combined with one SIM card number, and used as the auxiliary input to a Java Virtual Machine when the program is executed. The obfuscated interpretation enables us to hide functionality of a given program P unless the permutation being taken is revealed. The permutation space is sufficiently large, which ensure successful attacks on one´s embedded copyright protection mechanism cannot be generalized successfully to other installed copies. Experimental result shows that there is little influence to the file size and execution efficiency.