Leakage-Resilient Anonymous Multi-Receiver Outsourced Revocable Certificateless Encryption

To reduce the complexity of managing certificates in public-key infrastructure (PKI)-based public key systems (PKI-PKS) and solve the key escrow issue in identity (ID)-based public-key systems (ID-PKS), certificateless public-key systems (CL-PKS) are proposed and play an important role in public-key cryptography. But, a CL-PKS setting should consider the revocation issue to revoke intruded members so that a revocable certificateless public-key setting (RCL-PKS) is used to resolve this issue. Recently, side-channel attacks have been realized and endangered the existing cryptographic schemes/protocols. Fortunately, the research of leakage-resilient cryptographic schemes/protocols resisting such attacks have attracted the attention of cryptologists. Indeed, several leakage-resilient certificateless encryption (LR-CLE) schemes have been proposed. However, these LR-CLE schemes have some deficiencies. In the paper, the first leakage-resilient anonymous multi-receiver outsourced revocable certificateless encryption (LRAMR-ORCLE) scheme is proposed. As compared with several previous schemes, the proposed scheme possesses several merits: (1) The revocation functionality is performed by an outsourced revocation authority; (2) It guards against side-channel attacks and possesses leakage-resilient property; (3) An authorized receiver's identity is anonymous for other receivers; (4) It is a secure one-to-many encryption scheme.