Monetary loss due to software piracy nowadays reaches millions. In 2017, the commercial value for this concept rose to $46.3 billion. A way to mitigate this problem from the technological point of view is the use of software protection techniques, especially the obfuscation and diversification of code, highlighting the control obfuscation. There are many proposals connected with obfuscating control flow graph. However, there are few reported works that perform obfuscation of the call graph. In this study, the authors propose a novel mechanism for the static obfuscation and diversification of the call graph of a software. The mechanism is based on the routing of functions calls in order to modify the software call graph. A prototype of the proposed mechanism was developed by extending the functionalities of a compiler. The generated software differed structurally by 25% on average, compared to the original software. There was an increase in the level of obfuscation from 2 to 30% in the tests performed, with only a 3% overhead of the execution time in all cases. The proposal allows to restructure the whole call graph efficiently, increasing the level of protection without affecting significantly the software performance.

中文翻译：

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调用图模糊化和多样化：一种方法

如今，由于软件盗版而造成的金钱损失达数百万美元。2017年，该概念的商业价值上升至463亿美元。从技术角度来看，减轻此问题的一种方法是使用软件保护技术，尤其是代码的混淆和多样化，突出控制混淆。有许多与模糊控制流程图有关的建议。但是，很少有报道对电话图表进行混淆处理。在这项研究中，作者提出了一种用于软件的调用图的静态混淆和多样化的新机制。该机制基于函数调用的路由，以便修改软件调用图。通过扩展编译器的功能，开发了所提出机制的原型。与原始软件相比，生成的软件在结构上平均相差25％。在执行的测试中，混淆的程度从2％增加到30％，在所有情况下执行时间的开销仅为3％。该提议允许有效地重组整个调用图，从而在不显着影响软件性能的情况下提高保护级别。