Provably Secure and Efficient Proxy Signature with Untrustworthy Proxy Signer

摘要

Proxy signature has drawn great concerns.However,there still remains a challenge to construct a provably secure and efficient proxy signature scheme.In this paper,we propose an efficient proxy signature scheme based on factoring,and prove that it is secure in the random oracle.Furthermore,we present a new type of proxy signature,called Proxy Signature with Untrustworthy Proxy Signer,and construct a concrete scheme.