一种基于身份的代理可验证加密签名方案

Identity-Based Proxy Verifiably Encrypted Signature Scheme

A Verifiably Encrypted Signature (VES) plays an essential role in the construction of a fair data exchange. The paper proposes an Identity-based Proxy Verifiably Encrypted Signature (IPVES) to combine the advantages of a proxy sig-nature and a VES in order to delegate the signing capability of the VES of an entity called the original signer to another entity, called the proxy signer. In this IPVES scheme, the original signer delegates his/her signing capability to the proxy signer. The proxy signer issues a signature by using a proxy signing key, encrypts the signature under a desig-nated public key, and subsequently convinces a ver-ifier that the resulting ciphertext contains such a signature. We prove that the proposed IPVES scheme is secure in a random oracle model under the computational Diffie-Hellman assumption.