Paper 2017/619

Black-Box Constructions of Signature Schemes in the Bounded Leakage Setting

Qiong Huang and Jianye Huang

Abstract

To simplify the certificate management procedures, Shamir introduced the concept of identity-based cryptography (IBC). However, the key escrow problem is inherent in IBC. To get rid of it, Al-Riyami and Paterson introduced in 2003 the notion of certificateless cryptography (CLC). However, if a cryptosystem is not perfectly implemented, adversaries would be able to obtain part of the system's secret state via side-channel attacks, and thus may break the system. This is not considered in the security model of traditional cryptographic primitives. Leakage-resilient cryptography was then proposed to prevent adversaries from doing so. There are fruitful works on leakage-resilient encryption schemes, while there are not many on signature schemes in the leakage setting. In this work, we review the folklore generic constructions of identity-based signature and certificateless signature, and show that if the underlying primitives are leakage-resilient, so are the resulting identity-based signature scheme and certificateless signature scheme. The leakage rate follows the minimum one of the underlying primitives. We also show some instantiations of these generic constructions.