Revocable identity-based matchmaking encryption in the standard model

作者：Jiang, Zhe; Wang, Xiwen; Zhang, Kai^*; Gong, Junqing; Chen, Jie; Qian, Haifeng

来源：IET Information Security, 2023, 17(4): 567-581.

DOI：10.1049/ise2.12116

• cryptography
• public key cryptography

Identity-based Matchmaking Encryption (IB-ME) is an extension notion of matchmaking encryption (CRYPTO 2019), where a sender and a receiver can specify an access policy for the other party. In IB-ME, data encryption is performed by not only a receiver identity but also a sender's encryption key. Nevertheless, previous IB-ME schemes have not considered the problem of efficient revocation. Hence, the authors introduce a new notion of revocable IB-ME (RIB-ME) and formalise the syntax and security model of RIB-ME. In particular, the authors give an effective and simple construction of RIB-ME in the standard model, whose security is reduced to the hardness of decisional bilinear Diffie-Hellman problem and computational Diffie-Hellman problem. In addition, the authors show two extensions of our RIB-ME scheme to consider chosen-ciphertext security and forward privacy.