Leakage-Resilient Certificateless Signature Under Continual Leakage Model

In the past, the security notions of cryptography were modeled under the assumption that private (or secret) keys are completely hidden to adversaries. Nowadays, these security notions could be insufficient due to a new kind of threat, called "side-channel attacks", by which an adversary obtains partial information of private (or secret) keys via employing specific properties resulting from physical implementations of cryptographic schemes. In order to resist such side-channel attacks, numerous leakage-resilient cryptographic schemes have been proposed. However, there is little work on studying leakage-resilient certificateless cryptographic schemes. In this article, we propose the first leakage-resilient certificateless signature (LR-CLS) scheme under the continual leakage model. In the generic bilinear group model, we demonstrate that our scheme possesses existential unforgeability against adaptive chosen-message attacks for both Type I and Type II adversaries. Finally, performance analysis is made to demonstrate that the proposed LR-CLS scheme is suitable for resource- constrained devices.