Abstract:

Currently, software cracking and piracy not only brings great hidden troubles for user's safety, but also brings huge losses for software developers. In order to resist the reverse engineering to analyze and crack the software and increase the difficulty of attackers’ reverse analysis to the codes, an effective method to protect the code instructions is needed. Instruction virtualization technology achieves the purpose of software protection by using custom virtual instruction set to replace the native instruction set. According to the present software protection problems, this paper puts forward a code protection model based on the instruction virtualization, using custom virtual instruction set to replace the protected native instructions, reconstructing virtual environment to implement the original key codes by interpretation, and stripping out the explicit association between native instructions and context. Experimental tests show that the model can effectively resist the reverse analysis and achieve the purpose of protecting the software codes.

Key words: software protection, instruction virtualization, reverse analysis