用于软件保护的代码混淆技术选读.docx

江西师范大学 硕士学位论文 用于软件保护的代码混淆技术研究 姓名：杨乐 申请学位级别：硕士 专业：计算机系统结构 指导教师：薛锦云  Abstract Recently, mobile code technology has a great deal of development and promises well.However the security problem with mobile code technology obstructs its wide application in real business. Among these security problems, how to protect mobile code from malicious host is a new issue that cannot be dealt by traditional technologies. In malicious host surroundings ,a software can be reverse engineered and also can be tampered with. The confidentiality, integrality and availability of software are threatened, so convenient and effective methods are needed to protect the intellectual property contained in software. Code obfuscation transformation emerges as a defense technique to protect software form reverse engineering. The advent and widely use of Java language brings the widely research on code obfuscation because the class file is easy to be decompiled. So code obfuscation for software protection in malicious host attract much attention and there are very important theoretical and practical significance. This paper treated protecting software and using more costly forms of reverse engineering as target, deeply researched reverse engineering and code obfuscation about defense and attack. A prototype of Code obfuscation system (JOT) based on Java byte code is realized, the comprehensive system is an important manifestation for our research. Main contributions in the paper are: (1) Analysis the concept, classification and research methods of reverse engineering, and research the application of formal methods in reverse engineering. (2) Researches all kind of mainstream technologies of code obfuscation, including layout obfuscation, control obfuscation, data obfuscation, class obfuscation and preventive obfuscation. We demonstrated some properties of obfuscating transformation. (3) Design of a model for general protecting software with confidentiality, integrality, avail