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arXiv · 2011.08456

Collusion-Resistant Identity-based Proxy Re-Encryption: Lattice-based Constructions in Standard Model

Priyanka Dutta·Willy Susilo·Dung Hoang Duong·Partha Sarathi Roy
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Abstract

The concept of proxy re-encryption (PRE) dates back to the work of Blaze, Bleumer, and Strauss in 1998. PRE offers delegation of decryption rights, i.e., it securely enables the re-encryption of ciphertexts from one key to another, without relying on trusted parties. PRE allows a semi-trusted third party termed as a ``proxy" to securely divert encrypted files of user A (delegator) to user B (delegatee) without revealing any information about the underlying files to the proxy. To eliminate the necessity of having a costly certificate verification process, Green and Ateniese introduced an identity-based PRE (IB-PRE). The potential applicability of IB-PRE sprung up a long line of intensive research from its first instantiation. Unfortunately, till today, there is no collusion-Resistant unidirectional IB-PRE secure in the standard model, which can withstand quantum attack. In this paper, we present the first concrete constructions of collusion-Resistant unidirectional IB-PRE, for both selective and adaptive identity, which are secure in standard model based on the hardness of learning with error problem.

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Priyanka Dutta, Willy Susilo, Dung Hoang Duong, Partha Sarathi Roy. 2020-11-16. Collusion-Resistant Identity-based Proxy Re-Encryption: Lattice-based Constructions in Standard Model. https://arxiv.org/abs/2011.08456

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