Overview of Dual rail with Precharge logic styles to thwart implementation-level attacks on hardware cryptoprocessors

The security of cryptographic implementations relies not only on the algorithm quality but also on the countermeasures to thwart attacks aiming at disclosing the secrecy. These attacks can take advantage of leakages of the secret appearing through the power consumption or the electromagnetic radiations also called ¿Side Channels¿. This is for instance the case of the Differential Power Analysis (DPA) or the Correlation Power Analysis (CPA). Fault injections is another threatening attack type targeting specific nets in a view to change their value. The major principle to fight the side-channel attack consists in making the power consumption constant. The masking method allows the designer to get a power consumption which has a constant mean and a variance given by a random variable. Another manner is the Hiding method which consists in generating a constant power consumption by using a Dual-rail with Precharge phase Logic (DPL). This paper presents an overview of the various logic styles that have been promoted in the last six years, with an emphasis on their relative advantages and drawbacks.