JUCS - Journal of Universal Computer Science 25(3): 182-202, doi: 10.3217/jucs-025-03-0182

Provably Secure Ciphertext-Policy Attribute-Based Encryption from Identity-Based Encryption

Yi-Fan Tseng^‡, Chun-I Fan^§, Chih-Wen Lin^§

‡ National Chengchi University, Taipei, Taiwan§ National Sun Yat-sen University, Kaohsiung, Taiwan

Corresponding author: Yi-Fan Tseng ( yftseng1989@gmail.com )

This is an open access article distributed under the terms of the Creative Commons Attribution License (CC BY-ND 4.0). This license allows reusers to copy and distribute the material in any medium or format in unadapted form only, and only so long as attribution is given to the creator. The license allows for commercial use.

Citation: Tseng Y-F, Fan C-I, Lin C-W (2019) Provably Secure Ciphertext-Policy Attribute-Based Encryption from Identity-Based Encryption. JUCS - Journal of Universal Computer Science 25(3): 182-202. https://doi.org/10.3217/jucs-025-03-0182

Abstract

Ciphertext-policy attribute-based encryption (CP-ABE) is an access control mechanism where a data provider encrypts a secret message and then sends the ciphertext to the receivers according to the access policy which she/he decides. If the attributes of the receivers match the access policy, then they can decrypt the ciphertext. This paper shows a relation between CP-ABE and identity-based encryption (IBE), and presents a bi-directional conversion between an access structure and identities. By the proposed conversion, the CP-ABE scheme constructed from an IBE scheme will inherit the features, such as constant-size ciphertexts and anonymity, from the IBE scheme, and vice versa. It turns out that the proposed conversion also gives the first CP-ABE achieving access structures with wildcard and constant-size ciphertexts/private keys. Finally, we prove the CCA security for confidentiality and anonymity.

Keywords

attribute-based encryption, identity-based encryption, constant-size ciphertexts/keys, hidden access policies