Application Research Of Automatic Code Obfuscation Technology In Script Source Code Encryption

With the high-speed development of software industry, software security is more andmore attention, the importance of software intellectual property protection is becoming moreand more prominent, thus it more aroused people to study the software protection technology.The most commonly used software protection techniques mainly include: tamper-prooftechnology, code confusion, software encryption, software watermarking and digitalfingerprinting and DRM security protection technology, and so on.Code obfuscation is one kind of keep semantic program transformation technology, andmake the program after transformation compared with the original program has the same orsimilar function and behavior, but it can make the program readability is poor, thus itincreases the difficulty of the attacker to analysis program, so the attacker is difficult to obtainvaluable information, it also can effectively resist attacks of reverse engineering technology,so as to achieve the goal of protection software.This paper makes an intensive study of the application of encryption protection in scriptsource program, according to the common polymorphic obfuscation algorithm designprinciple, proving equivalence of obfuscation algorithm based on script and put forword thepolymorphism for PHP script language confusion scheme. On this basis, this paper proposesthe general script code based on automatic confusion system framework model, and gives theformal description of the code obfuscation system, The code obfuscation system mainlyinclude User Interface module, Preprocessing module, the management module ofobfuscation algorithm and actuator module, this system has realized the centralizedmanagement of the mixed algorithm and dynamic invocation. In order to analyze theperformance index of obfuscation, aiming at the performance indicators includingpolymorphism, concealment, additional costs, uncertainty and readability, experimentalresults and theoretical analysis are given. And the paper makes detailed introduction on theuncertainty of program.Giving mathematical calculation method and the concreteimplementation plan about measurement of uncertainty.This paper can provide reference for the further research of polymorphic obfuscationalgorithm based on script.