International Association
for Cryptologic Research

Secure computation in the presence of tamper-proof hardware tokens is proven under the assumption that the holder of the token is only given black-box access to the functionality of the token. Starting with the work of Goldreich and Ostrovsky [GoldreichO96], a long series of works studied tamper-proof hardware for realizing two-party functionalities in a variety of settings.

In this work we focus our attention on two important complexity measures of token-based secure computation: round complexity and hardness assumptions and present the following results in the two-party setting:

(1) A round optimal generic secure protocol in the plain model assuming one-way functions, where the tokens are created by a single party.

(2) A round optimal generic UC secure protocol assuming one-way functions.

Our constructions only make black-box use of the underlying primitives and are proven in the real/ideal paradigm with security in the presence of static malicious adversaries.