AES加密算法的密钥搜索量子线路设计

Key Search Quantum Circuit Design of AES Cipher

为验证量子搜索应用于分组密码密钥搜索的可行性,在分析AES算法计算流程和需要实现的计算模块的基础上,设计了一种AES算法密钥搜索的量子线路,包括密钥扩展KeyExpansion模块、量子加密模块和量子比较模块.其中,量子加密模块包含量子轮密钥加AddRoundKey、量子字节代换SubBytes、量子行移位ShiftRows和量子列混淆MixColumns.为了使辅助比特能被后续计算重用,采用回退计算方法去除量子纠缠,在实现量子加密模块时根据4个子模块的不同计算任务采取相应的回退计算策略,以节省计算时间和量子存储空间.研究结果表明:将量子搜索算法应用于分组密码的密钥穷举搜索攻击以达到二次方加速是可行的.

In order to verify the feasibility of applying the quantum search to the key search of block ciphers,a key search quantum circuit of AES（advanced encryption standard） cipher was designed,including KeyExpansion module,encryption module and comparison module,based on the analyses of its computation processes and computation modules needed to be achieved.The encryption module includes four sub-modules,i.e.,quantum AddRoundKey,SubBytes,ShiftRows and MixColumns.In order to reuse the working quantum bits,the reversible computation is used to eliminate the quantum entanglement effect,and different methods of the reversible computation are adopted to different tasks of the 4 sub-modules in the realization of the quantum encryption module so as to save computation time and quantum memory.The research shows that applying the quantum search scheme to the key search of block ciphers to save square root time is feasible.