密文类型可修改的基于格代理重加密方案.

In order to construct an efficient type-based proxy re-encryption scheme that can resist the quantum attack, this paper cryptanalyzed Zhang' s IBPRE scheme based on lattice, and shown that the scheme was vulnerable to collusion attack so that the private key was leaked. It presented the first dynamic type-based proxy re-encryption scheme based on lattice hard problem, whose security proved reduced to LWE assumption tightly. The construction was IND-CPA-secure cryptosystem. The scheme not only had the functions of the traditional type-based proxy re-encryption scheme, but also could resist the quantum attack, and the delegator of the ciphertext could modify the type of ciphertext dynamically. The proposed scheme is more useful in practical applications. [ABSTRACT FROM AUTHOR]