有效的标准模型下格上基于身份的代理重加密

Efficient Identity-based Proxy Re-encryption on Lattice in the Standard Model

代理重加密在云计算环境下的密文共享等方面起着重要的作用。目前格上基于身份的代理重加密方案都是随机预言机模型的。针对这个问题,该文构造了一个高效的标准模型下格上基于身份的代理重加密方案。在方案中,用户身份仅仅被映射为一个向量,使得用户私钥的尺寸较短。该方案具有双向性,多次使用性等性质,并且在LWE困难假设下是适应性选择身份CPA安全的。

Proxy re-encryption plays an important role for encrypted data sharing and so on in cloud computing.Currently,almost all of the constructions of identity-based proxy re-encryption over lattice are in the random oracle model.According to this problem,an efficient identity-based proxy re-encryption is constructed over lattice in the standard model,where the identity string is just mapped to one vector and getting a shorter secret key for users.The proposed scheme has the properties of bidirectional,multi-use,moreover,it is semantic secure against adaptive chosen identity and chosen plaintext attack based on Learning With Errors(LWE)problems in the standard mode.