Conditional Attribute-Based Proxy Re-Encryption and Its Instantiation [article]

Lisha Yao, Jian Weng, Bimei Wang
2022 IACR Cryptology ePrint Archive  
In attribute-based proxy re-encryption (AB-PRE) and attributebased conditional proxy re-encryption (AB-CPRE) systems, the proxy transforms a ciphertext associated with policy f to a ciphertext associated with policy g or transforms a ciphertext for delegator satisfying a fine-grained condition to a ciphertext for delegatee. However, such PRE schemes have found many practical applications requiring fine-grained access control while keeping flexible delegation. Unfortunately, the existing PRE
more » ... mes are impossible to handle simultaneously with the above scenarios. In this work, we introduce the notion of conditional attribute-based proxy re-encryption (CAB-PRE), which enables a proxy only to transform a ciphertext associated with policy f meeting the special delegation requirements by delegator to a ciphertext associated with policy g. We formalize its honestly re-encryption attacks (HRA) security model that implies CPA-secure, giving a concrete CAB-PRE scheme based on learning with errors (LWE) assumption. Finally, we show that CAB-PRE implies AB-PRE and AB-CPRE notions, and propose their constructions.
dblp:journals/iacr/YaoWW22 fatcat:hmmjyezq2jf6hhulbleihp5o6a