【作者】 王哲；

【导师】 张文英；

【作者基本信息】 山东师范大学 ， 计算机软件与理论， 2012， 硕士

【摘要】 信息系统安全的紧迫性和网络通信安全的重要性使人们越来越对分组密码的相关理论感兴趣，分组密码的设计与分析也一直是密码学中的热点课题。分组密码作为现代密码学中的一个重要研究分支，其诞生和发展有着广泛的实用背景和重要的理论价值。美国国家标准和技术研究所在经过一系列的评测后，从众多的分组密码中选中Rijndael算法，在2001年11月26日对外公布该算法作为AES算法[1,2,3,4]。AES算法作为美国数据加密标准算法，代表了国际密码界在分组密码设计与攻击领域的最高水平。因此对它的安全性分析是一个具有挑战性的课题，具有重大的密码学意义。围绕着AES算法的安全性分析，本文主要取得了以下研究成果：1、利用中间相遇攻击方法成功实现了对AES算法的前身Square算法[3]的研究。建立一个四轮分析器，分析出字节之间的组合关系，利用中间相遇攻击的思想，加密五轮，解密一轮后得到的函数值与事先准备的函数集合里的函数值进行比较，进而验证猜测的密钥正确与否；2、在倒数第四轮输入处植入故障，攻击了完整轮数的AES-128。在第七轮的输入诱导一个有故障差分的字节，进行四轮的运算得到错误密文值，通过正确密文与错误密文的差分值与字节之间的比例关系组成四个等式组，根据四个等式的比例关系猜测相关密钥，理论上需要使用两对明密文对就可以恢复正确的密钥。更多还原

【Abstract】 The urgency of the information system security and the importance network communicati-ons of safety make people are increasingly interested in theories of block cipher, block cipheranalysis and design also has been a hot topic in cryptography. Block cipher is an importantresearch branch of modern cryptography, its birth and development has a wide range of practicalbackground and important theoretical value.The USA National Institute of Standard and Technology Institute after a series of evaluation,selected Rijndael algorithm from a large number of block cipher , announced that the algorithmas the AES algorithm[1,2,3,4]in November 26, 2001. The AES algorithm as USA data encryptionstandard algorithm, represent the highest level of international cryptography sector in the field ofblock cipher design and attack. Thus safety analysis is a challenging task, and have a majorcryptography significance. Around the safety analysis of the AES algorithm, some achievementshave been obtained in this paper:The meet-in-the-middle attack methods successful analysis the AES algorithm predecessorSquare algorithm. First, we constructed a fourth round differentiator, then used the differentiatorto analyze the relations between bytes,used the idea of meet-in-the-middle attack,encryption fiveround，compare the values obtained by this decryption to the values in the precomputed set, thenverify that whether the guessed key correct or not;Induce a fault at the input of the last fourth round, attack complete AES-128. Induce a faultdifferential bytes in the input of the seventh round, then by four round operations to get the faultciphertext,composed of four equations by the proportional relationship between the differencevalue four equations proportional relationship guess keys, theoretically only required two pairsof plaintext and cipher to recovery the right key .更多还原