中文摘要：

分类代理重加密通过密码学手段为密文委托与分发提供了高效便捷的解决方案,同时使密文拥有者有能力实施更细粒度的委托控制.本文提出了一种新的分类代理重加密方案,方案在随机预言模型下可证明选择密文安全,相对于现有采用双线性对构造的分类代理重加密方案,我们的无双线性对方案拥有更好的效率,并具备主密钥安全性.

英文摘要：

Type-based proxy re-encryption is an effective and efficient cryptographic solution to ciphertext delegation and distribution, which also enables the ciphertext owners to carry out fine-grained delegation control. In this paper, we propose a new type-based proxy re-encryption scheme without pairings and prove it against the chosen-ciphertext attack （CCA） in the random ora- cle model. Compared with the existing type-based proxy re-encryption schemes constructed with pairings, our scheme owns better ef- ficiency as well as the master key security.