Cryptology ePrint Archive: Report 2021/778

Efficient secret key reusing attribute-based encryption from lattices

Xinyuan Qian and Wenyuan Wu

Abstract: Attribute-based encryption (ABE) schemes by lattices are likely to resist quantum attacks, and can be widely applied to many Internet of Thing or cloud scenarios. One of the most attractive feature for ABE is the ability of fine-grained access control which provides an effective way to ensure data security. In this work, we propose an efficient ciphertext policy attribute-based encryption scheme based on hardness assumption of LWE. Being different from other similar schemes, a user's secret key can only be generated once only and it can be used to decrypt ciphertext under different access policies by making combinations of secret key fragments. Specially, we propose a method for binding users' secret keys with their attributes and identities, which solves the collusion attack problem. The security of the scheme is proved to be selective secure under the LWE assumption.

Category / Keywords: public-key cryptography / Ciphertext policy attribute-based encryption; Learning with error; Access Structure; Secret key resuing

Date: received 9 Jun 2021

Contact author: xinyuanqian at outlook com

Available format(s): PDF | BibTeX Citation

Version: 20210609:132623 (All versions of this report)

Short URL: ia.cr/2021/778


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