Diffusional Side-Channel Leakage From Unrolled Lightweight Block Ciphers: A Case Study of Power Analysis on PRINCE

This study investigates a new side-channel leakage observed in the inner rounds of an unrolled hardware implementation block ciphers chosen-input attack scenario. The occurs first round and it can be later because arises from path activation bias caused by difference between two consecutive inputs. Therefore, that exploits is possible even for implementations equipped with countermeasures (masking and/or deglitchers separate circuit terms glitch propagation) involving leakage. We validate existence such unique through set experiments fully PRINCE cipher hardware, implemented on field-programmable gate array (FPGA). In addition, we verify validity evaluate cost countermeasure implementation, namely Threshold Implementation (TI) countermeasure.