Tamper-resistant cryptographic hardware

Secure Audit Logging with Tamper-Resistant Hardware

Secure perimeter schemes (e.g. DRM) and tracing traitor schemes (e.g. watermarking, audit logging) strive to mitigate the problems of content escaping the control of the rights holder. Secure audit logging records the user’s actions on content and enables detection of some forms of tampering with the logs. We implement Schneier and Kelsey’s secure audit logging protocol [1], strengthening the p...

Cryptographic Tamper Evidence

Cryptographic Tamper Evidence

Specifying and Verifying Hardware for Tamper-Resistant Software

We specify a hardware architecture that supports tamper-resistant software by identifying an “idealized” model, which gives the abstracted actions available to a single user program. This idealized model is compared to a concrete “actual” model that includes actions of an adversarial operating system. The architecture is verified by using a finite-state enumeration tool (a model checker) to com...

Fast Primitives for Internal Data Scrambling in Tamper Resistant Hardware

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 l...