Abstract

In this paper we describe a new algorithm to prevent fault attacks on RSA signature algorithms using the Chinese Remainder Theorem (CRT-RSA). This variant of the RSA signature algorithm is widely used on smartcards. Smartcards on the other hand are particularly susceptible to fault attacks like the one described in [7]. Recent results have shown that fault attacks are practical and easy to accomplish ([21], [17]). Therefore, they establish a practical need for fault attack protected CRT-RSA schemes. Starting from a careful derivation and classification of fault models, we describe a new variant of the CRT-RSA algorithm. For the most realistic fault model described, we rigorously analyze the success probability of an adversary. Thereby, we prove that our new algorithm is secure against the Bellcore attack. Only once in the analysis do we need to refer to a plausible number theoretic assumption. Categories and Subject Descriptors B.8.1 [Reliability, Testing, and Fault-Tolerance]: fault attacks; C.3 [Special-Purpose and Application-based

Citations