Compact Attribute-Based Encryption and Signcryption for General Circuits from Multilinear Maps

• Published in: Progress in Cryptology -- INDOCRYPT 2015 pp. 3 - 24
• Main Authors: Datta, Pratish, Dutta, Ratna, Mukhopadhyay, Sourav
• Format: Book Chapter
• Language: English
• Published: Cham Springer International Publishing 2015
• Series: Lecture Notes in Computer Science
• Subjects: ABE; ABSC; Multilinear map; Polynomial-size circuits
• ISBN: 3319266160; 9783319266169
• ISSN: 0302-9743; 1611-3349
• DOI: 10.1007/978-3-319-26617-6_1

In this paper, we start by presenting a key-policy attribute-based encryptionABE supporting general polynomial-size circuit realizable decryption policies and featuring compactness in the sense that our ABE construction exhibits short ciphertexts and shorter decryption keys compared to existing similar works. We then design a key-policy attribute-based signcryptionABSC scheme which enjoys several interesting properties that were never achievable before. It supports signing and decryption policies representable as arbitrary polynomial-size circuits. Besides, it generates short ciphertext. Our constructions employ multilinear map and achieve selective security in the standard model under standard complexity assumptions. More interestingly, our key-policy constructions can be converted to the corresponding ciphertext-policy variants achieving short ciphertext by utilizing the technique of universal circuits.