基于Petri网编码的动态图水印技术研究

Study on Dynamic-graph Watermarking Based on Petri Net Coding

针对动态水印数据嵌入率低的问题,提出一种基于Petri网编码的动态图水印算法。首先,将水印信息进行数列转换,然后将其编码至Petri网的运行状态序列中,最后将生成该Petri网结构的代码嵌入至受保护软件的源代码中。利用Petri网中变迁的发生会产生不同标识的特点,应用同一个Petri网结构表达多个数值,使得该水印编码方案在具有较高的数据嵌入率的同时还具有一定的检错能力,能够成功抵抗包括添加结点、删除部分变迁、删除部分库所和删除部分弧等多种典型的攻击。最后通过实验验证了相关算法的可行性和有效性,并进行了扭曲攻击测试,结果表明基于Petri网编码的动态图软件水印技术具有很强的抗扭曲攻击能力以及鲁棒性。

Aiming at the problem of low data embedding rate of dynamic watermarking,this paper proposed a dynamic-graph watermarking algorithm based on Petri net coding.First,the watermark information is converted into a sequence,and then it is encoded into a running state sequence of Petri net.Finally,the code that generates the Petri net structure is embedded into the source code of the protected software.Since the Petri net transitions will produce different marks,the multiple values are expressed in the same Petri network structure,which means that the watermarking scheme has high data embedding rate and error detection ability,and can successfully resist multiple and typical attacks such as the insertion of nodes,the deletion of transitions,the deletion of places and the deletion of arcs.Finally,the feasibility and effectiveness of the algorithm were verified in the experiment,and the distortion attack test was carried out.The result shows that the dynamic map software watermark based on Petri net coding is robust,and it has a strong ability to resist distortion.