An Efficient Proxy Re-Encryption Based on (Semi) Group Factorization Problems

Abstract

Proxy re-encryption (PRE) enables a semi-trustedproxy to transfer Alice's secrets into Bob's secrets but withoutseeing the secrets. This functionality is very interesting formaking balance between the information confidentiality and the mutual accessibility in various scenarios such as public cloudstorage systems. During the past decades, many smart PREschemes were built based on intractability assumptions suchas integer factorization problems (IFP) and discrete logarithmproblems (DLP). However, Shor's efficient quantum algorithmsfor IFP and DLP manifests a threat towards the securitybaseline of these schemes. Enlightened by Gu et al.'s recent workon resisting known quantum attacks, we propose an efficientPRE scheme based on the intractability of the (semi) groupfactorization problems in this paper. The security of the proposedscheme is analyzed according to some conceivable attacks.