Volume 31, Issue 3 (2020), pp. 597–620
Very recently, side-channel attacks have threatened all traditional cryptographic schemes. Typically, in traditional cryptography, private/secret keys are assumed to be completely hidden to adversaries. However, by side-channel attacks, an adversary may extract fractional content of these private/secret keys. To resist side-channel attacks, leakage-resilient cryptography is a countermeasure. Identity-based public-key system (ID-PKS) is an attractive public-key setting. ID-PKS settings not only discard the certificate requirement, but also remove the construction of the public-key infrastructure. For solving the user revocation problem in ID-PKS settings, revocable ID-PKS (RID-PKS) setting has attracted significant attention. Numerous cryptographic schemes based on RID-PKS settings have been proposed. However, under RID-PKS settings, no leakage-resilient signature or encryption scheme is proposed. In this article, we present the first leakage-resilient revocable ID-based signature (LR-RIBS) scheme with cloud revocation authority (CRA) under the continual leakage model. Also, a new adversary model of LR-RIBS schemes with CRA is defined. Under this new adversary model, security analysis is made to demonstrate that our LR-RIBS scheme with CRA is provably secure in the generic bilinear group (GBG) model. Finally, performance analysis is made to demonstrate that our scheme is suitable for mobile devices.
Pub. online:1 Jan 2018Type:Research ArticleOpen Access
Volume 29, Issue 1 (2018), pp. 125–155
The previous adversary models of public key cryptography usually have a nature assumption that permanent/temporary secret (private) keys must be kept safely and internal secret states are not leaked to an adversary. However, in practice, it is difficult to keep away from all possible kinds of leakage on these secret data due to a new kind of threat, called “side-channel attacks”. By side-channel attacks, an adversary could obtain partial information of these secret data so that some existing adversary models could be insufficient. Indeed, the study of leakage-resilient cryptography resistant to side-channel attacks has received significant attention recently. Up to date, no work has been done on the design of leakage-resilient certificateless key encapsulation (LR-CL-KE) or public key encryption (LR-CL-PKE) schemes under the continual leakage model. In this article, we propose the first LR-CL-KE scheme under the continual leakage model. Moreover, in the generic bilinear group (GBG) model, we formally prove that the proposed LR-CL-KE scheme is semantically secure against chosen ciphertext attacks for both Type I and Type II adversaries.