Attribute-Based Encryption Scheme with k-Out-of-n Oblivious Transfer

Abstract

Attribute-based encryption enables users to flexibly exchange and share files with others. In these schemes, users utilize their own attributes to acquire public-private key pairs from the key generation center. However, achieving this for users who wish to keep their attributes private poses a challenge. To address this contradiction, we propose an original scheme that combines ciphertext policy attribute-based encryption with a k-out-of-n oblivious transfer protocol. This scheme allows the distribution of corresponding public-private key pairs to users without the key generation center needing to obtain specific user attributes. Furthermore, it ensures the privacy of the key generation center. Security analysis demonstrates that the scheme is secure in the random oracle model. Our performance comparison and experimental results indicate that the scheme is both flexible and efficient.