代码混淆算法有效性评估

摘要

代码混淆是一种能够有效增加攻击者逆向分析和攻击代价的软件保护技术.然而,混淆算法的有效性评价和验证是代码混淆研究中亟待解决的重要问题.目前,对代码混淆有效性的研究大都是基于软件复杂性度量的,然而代码混淆作为一种保护软件安全的技术,更需要从逆向攻击的角度进行评估.将面向逆向工程的思想引入到代码混淆算法评估中,通过理论证明和具体实验验证了其可行性,该评估方法能够为混淆算法提供有效证明,并对判别和选择代码混淆算法具有指导意义,同时也有助于寻求更有效的代码混淆方法.%Code obfuscation is currently one of the most viable methods for preventing reverse engineering attacks. Many kinds of code obfuscation transforms are widely used in software protection. However, there are still no sufficient theories to evaluate the effectiveness of obfuscation transform. In fact, few measurements are available that provide information about the capability of obfuscation to reduce attackers' efficiency, and few existing theories, which draws upon complexity metrics from software engineering, are convincing. This paper uses a different way to evaluate the difficulty that attackers have in understanding and modifying obfuscated software through static analysis, dynamic debugging of reverse engineering, and then to abstract some metrics to quantify to what extent that code obfuscation is able to make attacks more difficult to be performed.