Hardware implementations of cryptographic algorithms are vulnerable to side-channel attacks. Side-channel attacks that are based on multiple measurements of the same operation can be countered by employing masking techniques. Many protection measures depart from an idealized hardware model that is very expensive to meet with real hardware. In particular, the presence of glitches causes many masking techniques to leak information during the computation of nonlinear functions. We discuss a recently introduced masking method which is based on secret sharing and multi-party computation methods. The approach results in implementations that are provably resistant against a wide range of attacks, while making only minimal assumptions on the hardware. We show how to use this method to derive secure implementations of some nonlinear building blocks for cryptographic algorithms. Finally, we provide a provable secure implementation of the block cipher Noekeon and verify the results by means of low-level simulations.
- DPA - Masking - Glitches - Sharing - Nonlinear functions - S-box - Noekeon