International Association for Cryptologic Research (IACR)
Abstract
Ciphertext-Policy Attribute-Based Encryption (CP-ABE) has been proposed to implement fine-grained access control. Data owners encrypt data with a certain access policy so that only data users whose attributes satisfy the access policy can decrypt the ciphertext. A user can be automatically assigned an access privilege based on whether his/her attributes satisfying a given access policy described by attributes and their logical relations. In order to provide more flexible policy-based access control, attribute-based revocation approaches had been proposed to provide the NOT logic on attributes to allow attribute-based revocation. However, previous solutions increase the attribute management overhead when considering each user’s ID as an attribute for more precise revocations at the individual user-level. To address this issue, in this paper, an ID-ABE scheme is presented, where a user’s ID is incorporated into the key generation procedure allowing user-ID-based revocation. In addition to ID-based revocation, ID-ABE also presents a hierarchical identity structure to build a delegation framework to enable group-based revocation. In the end, we also evaluate the performance of the proposed scheme in terms of computation, storage and communication overhead, which shows the practical value of the solution for secure data sharing applications