Abstract
Trusted Platform Modules (TPM) are multipurpose hardware chips, which provide support for various cryptographic functions. Flexibility, scalability and high performance are critical features for a TPM. In this paper, we present the new method for implementing digital signatures that has been included in TPM version 2.0. The core part of this method is a single TPM signature primitive, which can be called by different software programmes, in order to implement signature schemes and cryptographic protocols with different security and privacy features. We prove security of the TPM signature primitive under the static Diffie-Hellman assumption and the random oracle model. We demonstrate how to call this TPM signature primitive to implement anonymous signatures (Direct Anonymous Attestation), pseudonym systems (U-Prove), and conventional signatures (the Schnorr signature). To the best of our knowledge, this is the first signature primitive implemented in a limited hardware environment capable of supporting various signature schemes without adding additional hardware complexity compared to a hardware implementation of a conventional signature scheme.