Mdaak: A flexible and efficient framework for direct anonymous attestation on mobile devices

Abstract

In this paper, we investigate how to implement Direct Anonymous Attestation (DAA) on mobile devices, whose processing and storage capabilities are limited. We propose a generic framework providing a secure and efficient DAA functionality based on ARM TrustZone. Our framework is flexible enough to support multiple DAA schemes, and is efficient by leveraging the powerful ARM processor in secure mode to perform computations originally delegated to the Trusted Platform Module (TPM). Besides, our framework uses an SRAM PUF commonly available in the On-Chip Memory (OCM) of mobile devices for secure storage of user signing keys, which achieves a low-cost design. We present a prototype system that supports four DAA schemes on real TrustZone hardware, and give evaluations on its code size and performance together with comparisons of the four schemes with different curve parameters. The evaluation results indicate that our solution is feasible, efficient, and well-suited for mobile devices.