Preventing fault attack on stream cipher using randomization

Fault attacks are one of the most popular side channel attacks. It has been mounted on numerous stream ciphers successfully. Almost all the winners of the eSTREAM project have been cryptanalyzed using fault attack techniques even if they were shown to be secure against algebraic cryptanalysis techniques. Beside, very little research work exists in the contemporary literature to prevent fault attacks on stream ciphers and most of them are attack specific. This necessitates a generalized fault attack prevention technique for stream ciphers. In the current paper, fault attacks on stream ciphers are formalized and a generalized approach to thwart this kind of attacks is proposed using fault randomization. It is also proved that the proposed countermeasure nullifies the advantage of performing fault analysis techniques. We validate our scheme taking Grain-128 as crypto primitive along with FPGA implementation.