用于密码芯片的前馈异或安全扫描结构

Feedforward Xored Secure Scan Structure for Crypto Chips

扫描结构在给密码芯片增加可测性的同时也可能被不当使用为旁路攻击路径,使密码芯片的密钥信息泄露.为解决这个问题,提出一种前馈异或安全扫描结构.首先将异或安全扫描寄存器引入扫描结构中,该结构对测试图形进行输入?输出线性变换,实现对测试图形的硬件加密;然后分析了该结构的安全性并给出其测试图形生成算法.实验结果表明,文中提出的安全扫描结构能抗击基于扫描结构的旁路攻击和复位攻击,并保留了传统扫描结构的高测试覆盖率.

Scan structure increase the testability of crypto chips, however, it might be misused as a path of side-channel attack to leak out the secret information of crypto chips. To cope with such a challenge, a feedforward xored secure scan structure is proposed. The scan structure conducts an input/output linear transformation on the test patterns to hardware encrypt the test patterns by introducing feedforward xored secure scan flip-flops in the structure; and then the security of the structure is analyzed and its test pattern generation algorithm is presented. Experimental results show that the structure can be used as an effective countermeasure against scan based side channel attack and reset attack, while high test coverage of the traditional scan structure is maintained.