Post-Quantum Universal Composable OT Based on Key Exchange

• Main Authors: Ding Hangchao, Han Jiang, Qiuliang Xu
• Format: Article
• Language: English
• Published: IEEE 2020-01-01
• Series: IEEE Access
• Subjects: Oblivious transfer (OT); key exchange (KE); universally composable (UC); lattice assumption; RLWE (Ring-LWE); smooth projective hash function (SPHF)
• Online Access: https://ieeexplore.ieee.org/document/9157867/

We construct a universal composable framework for two-message oblivious transfer protocols based on lattice-assumption. Compared with the paper proposed by Liu and Hu, we modify a framework proposed by Liu and Hu by adding three tools, which are XOR, Bit Commitment and Smooth Projective Hash Function (SPHF). We instantiate Hash Function as SPHF, which can be more secure in practical application and can achieve full-simulatable in security proof. Compared with Hash Function used as Random Oracle in security proof, this construction is more secure and efficient in security proof. In particular, we mainly consider full-simulatable in simulation, which simulator can simulate any corruption cases. So we mainly consider non-adaptively malicious adversary in Oblivious Transfer protocols.