A Ciphertext Policy Attribute-Based Encryption Scheme without Pairings

Abstract

AbstractSahai and Waters [34] proposed Attribute-Based Encryption (ABE) as a new paradigm of encryption algorithms that allow the sender to set a policy to describe who can read the secret data. In recent years, lots of attribute-based schemes appeared in literatures, but almost all the schemes, to the best of our knowledge, are constructed from pairings. In this work, we present a ciphertext policy attribute-based encryption (CP-ABE) scheme, which supports and-gates without pairings. Our scheme is defined on q-ary lattices, and has a very strong security proof based on worst-case hardness. More precisely, under the learning with errors (LWE) assumption, our CP-ABE scheme is secure against chosen plaintext attack in the selective access structure model. Though our scheme only encrypts one bit at a time, we point out that it can support multi-bit encryption by using a well-known technique. Besides, our result can be easily extended to ideal lattices for a better efficiency.KeywordsAccess StructureIdeal LatticeCryptology ePrint ArchiveChoose Plaintext AttackLearn With ErrorThese keywords were added by machine and not by the authors. This process is experimental and the keywords may be updated as the learning algorithm improves.