Chapter

Cryptographic Hardware and Embedded Systems – CHES 2012

Volume 7428 of the series Lecture Notes in Computer Science pp 41-57

Simple Photonic Emission Analysis of AES

Photonic Side Channel Analysis for the Rest of Us
  • Alexander SchlösserAffiliated withOptical Technologies, Technische Universität Berlin
  • , Dmitry NedospasovAffiliated withSecurity in Telecommunications, Technische Universität Berlin
  • , Juliane KrämerAffiliated withSecurity in Telecommunications, Technische Universität Berlin
  • , Susanna OrlicAffiliated withOptical Technologies, Technische Universität Berlin
  • , Jean-Pierre SeifertAffiliated withSecurity in Telecommunications, Technische Universität Berlin

Abstract

This work presents a novel low-cost optoelectronic setup for time- and spatially resolved analysis of photonic emissions and a corresponding methodology, Simple Photonic Emission Analysis (SPEA). Observing the backside of ICs, the system captures extremly weak photoemissions from switching transistors and relates them to program running in the chip. SPEA utilizes both spatial and temporal information about these emissions to perform side channel analysis of ICs. We successfully performed SPEA of a proof-of-concept AES implementation and were able to recover the full AES secret key by monitoring accesses to the S-Box. This attack directly exploits the side channel leakage of a single transistor and requires no additional data processing. The system costs and the necessary time for an attack are comparable to power analysis techniques. The presented approach significantly reduces the amount of effort required to perform attacks based on photonic emission analysis and allows AES key recovery in a relevant amount of time.

Keywords

Photonic side channel emission analysis optical temporal analysis spatial analysis AES full key recovery