Cryptographic Hardware and Embedded Systems — CHES 2001

Volume 2162 of the series Lecture Notes in Computer Science pp 16-27


Fast Primitives for Internal Data Scrambling in Tamper Resistant Hardware

  • Eric BrierAffiliated withCard Security Group, Gemplus Card International
  • , Helena HandschuhAffiliated withGemplus Card International
  • , Christophe TymenAffiliated withÉcole Normale Supérieure


Although tamper-resistant devices are specifically designed to thwart invasive attacks, they remain vulnerable to micro-probing. Among several possibilities to provide data obfuscations, keyed hardware permutations can provide compact design and easy diversification. We discuss the efficiency of such primitives, and we give several examples of implementations, along with proofs of effectively large key-space.


Tamper-resistance Probing attacks Data scrambling Keyed permutations Smart-cards