Efficient Certificateless Ring Signcryption Scheme with Constant Ciphertext Length on Blockchain

Ring signcryption schemes have been proposed on blockchain, but compared with ring signcryption using public key infrastructure (PKI), certificateless can simplify the certificate management process. At the same time, the length of the ciphertext increases with the size of the ring is also a pressing challenge to be solved. In this paper, we propose a new certificateless ring signcryption scheme with constant ciphertext length and prove the security under the random oracle model. Compared with other schemes, the computational overhead of this scheme is smaller and more efficient.