Research And Design Of Anonymous Certificateless Multi-Receiver Signcryption Scheme

As a way to achieve the secure multicast communication,certificateless multi-receiver signcryption has higher computational efficiency and lower communication cost compared with one-to-one unicast communication which encrypts the message repeatedly,so it has attracted wide attention and application.Certificateless multi-receiver signcryption schemes can generate the same one signcryption ciphertext corresponding to the message for multiple receivers through only one signcryption process,and each receiver can independently decrypt the signcryption ciphertext to obtain the same message.With more and more attention paid to privacy protection,receiver anonymity and sender anonymity have been introduced into certificateless multi-receiver signcryption schemes.Receiver anonymity is developing very well,but the development of sender anonymity is poor.And there is no multi-receiver signcryption scheme to consider the trace function of malicious anonymous sender.In addition,the security of the partial private key depends on a secure channel in all certificateless multi-receiver signcryption schemes,which aggravates the burden of the system.Aiming at the sender anonymity and the tracing of malicious anonymous sender,a traceable anonymous certificateless multi-receiver signcryption scheme is proposed in this paper.In this scheme,we construct an ingenious relationship between the public key and the private key,so that only when the sender is a legitimate user in the system,the message sent by the sender can be correctly decrypted and accepted by authorized receivers.When the sender sends illegal messages,authorized receivers can make an application to the key generation center to trace the sender.If the application is approved,the key generation center can cooperate with any authorized receiver to trace the sender.In this way,the privacy of legitimate senders is protected,while malicious senders will be traced.In addition,we use a modular polynomial technology to mix and hide the information of authorized receivers,which achieves the receiver anonymity.Subsequently,deeply analyzing the scheme,we found that in the key generation process,the user's partial private key is sent to the user by the key generation center through a secure channel,which not only makes the security of the partial private key totally depend on the secure channel,but also brings additional cost of maintaining the secure channel to the system.This problem not only exists in our traceable anonymous certificateless multireceiver signcryption scheme,but also in all certificateless multi-receiver signcryption schemes.To solve this problem,an anonymous certificateless multi-receiver signcryption scheme in public environment is proposed in this paper.In this scheme,the key generation center uses public channel instead of the security channel to transmit the pseudo partial private key to the user,and then the user obtains the real partial private key by calculating,which improves the security of the partial private key and reduces the cost of the system.This paper mainly studies the certificateless multi-receiver signcryption scheme and reviews its development in recent years,finds out the problems still need to be solved,and then designs schemes to achieve the sender anonymity,the traceability of anonymous sender and the avoidance of the secure channel.The schemes proposed in this paper can provide message confidentiality,unforgeability,receiver anonymity and decryption fairness,and can be used in network conference,distance education,Pay-TV programs,cloud data sharing and other fields.