Silent Simon: A threshold implementation under 100 slices

Lightweight Cryptography aims at achieving security comparable to conventional cryptography at a much lower cost. Simon is a lightweight alternative to AES, as it shares same cryptographic parameters, but has been shown to be extremely area-efficient on FPGAs. However, in the embedded setting, protection against side channel analysis is often required. In this work we present a threshold implementation of Simon. The proposed core splits the information between three shares and achieves provable security against first order side-channel attacks. The core can be implemented in less than 100 slices of a low-cost FPGA, making it the world smallest threshold implementation of a block-cipher. Hence, the proposed core perfectly suits highly-constrained embedded systems including sensor nodes and RFIDs. Security of the proposed core is validated by provable arguments as well as practical DPA attacks and tests for leakage quantification.