New Countermeasures Against Differential Fault Attacks

As a kind of classical side channel attacks, differential fault attacks (DFA) has some favorable properties, such as the flexible fault injections, lower attack complexity and so on, which usually induces a serious threat to the engineering application of encryption algorithms. At present, how to resist DFA has became an important research topic. In this paper, a new general protection scheme against DFA is proposed by combining the basic idea of fault detection and infective countermeasure. Specifically, in this scheme, some fresh random values are used to scramble the difference of ciphertexts and the infective function so that the secret key information in the encryption process cannot be derived. In particular, the new scheme can not only resist to double fault attacks, but also can quickly determine the exact fault injected location of the target encryption cipher. It has the advantages of higher accuracy, easier implementation and less time complexity. As a application, the protection scheme for the Pyjamask authentication encryption algorithm is also presented, where Pyjamask cipher is current one of the second round candidate algorithms of lightweight ciphers competition by the National Institute of Standards and Technology (NIST). Moreover, the Skinny encryption algorithm is used as the encryption function for infective calculation to scramble the secret key information of cipher. It is illustrated this scheme can effectively protect the Pyjamask cipher against DFA in practical simulations.