Blockchain-based mutual authentication protocol without CA

Nowadays, most of the federation chain identity authentication adopts the certificate authentication of CA (Certification Authority) under PKI (Public Key Infrastructure) system, but the authentication of CA is one-way authentication, and users cannot evaluate the trustworthiness of CA, and its centralized structure is prone to the single point of failure, which will bring great security risks. To address this problem, we propose an efficient and reliable two-way authentication scheme to achieve membership authentication of the federated chain through elliptic curves and bilinear pairs. Membership authentication is performed directly by the federated chain supervisor through smart contracts, and then key negotiation is conducted among members, and the shared key determined after key negotiation generates a hash digest through a hash function as the unique transaction address of the federated chain members. This scheme can effectively solve the problems of CA one-way authentication and the easy failure of centralized CA. Through experimental and theoretical analysis, the scheme is able to resist multiple attacks and performs better in terms of overhead compared with the same type of protocol. We also design a scheme using Lagrangian interpolation to cope with the necessary key recovery and key update.