Research And Application Of Identity-based Homomorphic Signcryption Scheme

With the rapid development of the fifth generation mobile communication system,it provides users with stable and smooth communication services,some major identity information of users will inevitably be obtained in the process of service,which may lead to the serious problem of user privacy data leakage,such as mobile phone number,location information,etc.In this order,this paper studied the identity-based homomorphic signcryption scheme.The main works are as follows:Firstly,a new efficient identity-based signcryption scheme was proposed.The proposed signcryption scheme was realized in one logical step by using quadratic residual hard problem and Jacobi symbolic operation,which was proved to satisfy the confidentiality and unforgeability under the random oracle model.The efficiency analysis shows the proposed scheme greatly improves the computing efficiency and has good characteristics of identity-based cryptosystem.Secondly,a homomorphic identity signcryption scheme was proposed based on quadratic residue,the formal definition of the scheme and security model were given,which included the confidentiality and the unforgeability.An identity-based additive homomorphic signcryption scheme was constructed by using elements of polynomial quotient ring as ciphertext of Cocks scheme,and then,the homomorphism and security of the scheme were proved by using homomorphism function,quadratic residual hard problem and Galbraith test,and the proposal satisfies additive homomorphism,confidentiality,unforgeability and anonymity.The performance analysis shows the scheme not only ensured the security,but greatly reduced the ciphertext expansion rate.Finally,an identity-based homomorphic signcryption scheme for QR code was designed.To the problem that QR code is not easy to recognize the identity of the publisher and the information is easy to tamper.The signcryption was used before the coding of QR code,which can improve the security and retain the symbol characteristics of the QR code,and satisfy the public verification of identity authentication of the sender of the QR code.