Cryptology ePrint Archive: Report 2013/667

A TPM Diffie-Hellman Oracle

Tolga Acar and Lan Nguyen and Greg Zaverucha

Abstract: This note describes a Diffie-Hellman oracle, constructed using standard Trusted Platform Module (TPM) signature APIs. The oracle allows one to compute the exponentiation of an arbitrary group element to a specified TPM-protected private key.

By employing the oracle, the security provided by a group of order p is reduced by log k bits, provided k oracle queries are made and p +/- 1 is divisible by k. The security reduction follows from a straightforward application of results from Brown and Gallant (IACR ePrint 2004/306) and Cheon (Eurocrypt 2006) on the strong Diffie-Hellman problem.

On a more positive note, the oracle may allow a wider range of cryptographic protocols to make use of the TPM.

Category / Keywords: trusted platform module, strong diffie-hellman problem, cryptographic hardware

Date: received 18 Oct 2013, last revised 23 Oct 2013

Contact author: gregz at microsoft com

Available format(s): PDF | BibTeX Citation

Version: 20131024:081317 (All versions of this report)

Discussion forum: Show discussion | Start new discussion


[ Cryptology ePrint archive ]