Authenticache: Harnessing cache ECC for system authentication

Hardware-assisted security is emerging as a promising avenue for protecting computer systems. Hardware based solutions, such as Physical Unclonable Functions (PUF), enable system authentication by relying on the physical attributes of the silicon to serve as fingerprints. A variety of PUF designs have been proposed by researchers, with some gaining commercial success. Virtually all of these systems require dedicated PUF hardware to be built into the processor or System-on-Chip (SoC), increasing the cost of deployment in the field. This paper presents Authenticache, a novel, low-cost PUF design that does not require dedicated hardware support. Instead, it leverages on-chip error correction logic already built into many processor caches. As a result, Authenticache can be deployed and used by many off-the-shelf processors with minimal costs. We prototype, evaluate, and test the design on a real system, in addition to conducting extensive simulations. We find Authenticache to have high identifiability, as well as excellent resilience to measurement and environmental noise. Authenticache can withstand up to 142% of noise while maintaining a misidentification rate that is below 1 ppm.