Side Channel Attacks on Irregularly Decimated Generators

We investigate three side channel attacks on ABSG, a variant of irregularly decimated generators (IDG). The three attacks are timing analysis, phase-shift fault analysis and bit-flipping fault analysis. We also modify the attacks to non side-channel cryptanalyses, but on the assumption that the key/IV mixing is not well designed. This paper hopes to provide more understanding on actual hardware implementations of IDG as cipher components. Finally, we combine our fault analysis on ABSG with linearization attack to cryptanalze DECIM, an ESTREAM candidate cipher. We manage to reduce the attack complexity from 2 to 2.