Jiehui Nan, Mengce Zheng, Zilong Wang and Honggang Hu. A General Construction for Password-Based Authenticated Key Exchange from Witness PRFs

In cyber security, authenticated key exchange (AKE) can be used to achieve the privacy and authentication of data. As a relevant cryptographic protocol, password-based authenticated key exchange (PAKE) has been studied for its convenience. Recently, Katz and Vaikuntanathan proposed a round-optimal PAKE from smooth projective hash functions (SPHFs). However, the instantiation of smooth projective hash functions depends on the underlying NP-relation which is a CCA-secure encryption relation in their construction. In this paper, we apply a new cryptographic primitive named witness PRFs to construct PAKE. In our settings, the concrete construction of witness PRFs is independent of the underlying NP-relation. At this point, our construction is more general, and furthermore, we have a discussion on some possible NP-relations, which could be used to construct secure PAKE in our settings.