Visible to the public Generic Approach to Outsource the Decryption of Attribute-Based Encryption in Cloud Computing

TitleGeneric Approach to Outsource the Decryption of Attribute-Based Encryption in Cloud Computing
Publication TypeJournal Article
Year of Publication2019
AuthorsQin, Baodong, Zheng, Dong
JournalIEEE Access
KeywordsABE ciphertext, ABE outsourcing schemes, Adaptation models, adaptive security, attribute-based encryption, authorisation, black box encryption, black-box way, cloud computing, composability, concrete constructions, efficient transformation key generation algorithm, Encryption, faster decryption time, generic approach, generic construction, Metrics, modified decryption outsourcing mode, OD-ABE scheme, outsourced decryption, outsourcing, private key cryptography, pubcrawl, public key cryptography, public transformation key, resilience, Resiliency, security model, selective security model, shorter bit length, Standards, underlying ABE scheme, underlying standard ABE

The notion of attribute-based encryption with outsourced decryption (OD-ABE) was proposed by Green, Hohenberger, and Waters. In OD-ABE, the ABE ciphertext is converted to a partially-decrypted ciphertext that has a shorter bit length and a faster decryption time than that of the ABE ciphertext. In particular, the transformation can be performed by a powerful third party with a public transformation key. In this paper, we propose a generic approach for constructing ABE with outsourced decryption from standard ABE, as long as the later satisfies some additional properties. Its security can be reduced to the underlying standard ABE in the selective security model by a black-box way. To avoid the drawback of selective security in practice, we further propose a modified decryption outsourcing mode so that our generic construction can be adapted to satisfying adaptive security. This partially solves the open problem of constructing an OD-ABE scheme, and its adaptive security can be reduced to the underlying ABE scheme in a black-box way. Then, we present some concrete constructions that not only encompass existing ABE outsourcing schemes of Green et al., but also result in new selectively/adaptively-secure OD-ABE schemes with more efficient transformation key generation algorithm. Finally, we use the PBC library to test the efficiency of our schemes and compare the results with some previous ones, which shows that our schemes are more efficient in terms of decryption outsourcing and transformation key generation.

Citation Keyqin_generic_2019