Leakage-Resilient Anonymous Heterogeneous Multi-Receiver Hybrid Encryption in Heterogeneous Public-Key System Settings

Abstract

By side-channel attacks, a fraction part of secret keys used in cryptographic schemes could be leaked to adversaries. Recently, adversaries have realized practical side-channel attacks so that these existing cryptographic schemes could be broken. Indeed, researchers have invested and proposed a good approach to withstand such attacks, called as leakage-resilient cryptography. Very recently, several leakage-resilient anonymous multi-receiver encryption (LR-AMRE) schemes based on various public-key systems were also proposed. However, these LR-AMRE schemes are not suitable for a heterogeneous public-key environment under which an authorized receiver group includes heterogeneous receivers under various PKS settings and these receivers have various types of secret/public key pairs. In this article, we propose the $first$ leakage-resilient anonymous heterogeneous multi-receiver hybrid encryption (LR-AHMR-HE) scheme for the heterogeneous public-key system settings. A new framework and associated adversary games of the LR-AHMR-HE scheme are defined. In the adversary games, adversaries are admitted to continuously intercept a fraction part of secret keys. Under the adversary games, formal security proofs are provided to show that the proposed scheme is secure against two types of adversaries (illegitimate user and malicious authority). Comparisons with several related previous schemes are demonstrated to present the merits of our scheme.

Keywords

• Multi-receiver
• hybrid encryption
• heterogeneous public-key environment
• anonymity
• leakage-resilience
• unbounded leakage