DeKaRT: A New Paradigm for Key-Dependent Reversible Circuits

A new general method for designing key-dependent reversible circuits is proposed and concrete examples are included. The method is suitable for data scrambling of internal links and memories on smart card chips in order to foil the probing attacks. It also presents a new paradigm for designing block ciphers suitable for small-size and/or high-speed hardware implementations. In particular, a concrete building block for such block ciphers with a masking countermeasure against power analysis incorporated on the logical gate level is provided.