摘要
近年来,被广泛使用的MD5、SHA-1等哈希算法存在不同程度的安全隐患,现在通用的SHA-2算法迭代结构与SHA-1算法相同,使得其存在被攻破的可能性。而SHA-3由于其内部结构复杂,实现复杂度较高。设计并实现了基于混沌神经网络和C-MD(chaotic neural network-Merkle-Damgard)结构的带密钥哈希函数,为提高安全性改进了Merkle-Damgard结构,并提出C-MD结构,将该结构应用于哈希函数设计可以抵抗中间相遇攻击、多碰撞攻击以及针对长信息的第二原像攻击;使用混沌神经网络作为压缩函数,以提高哈希函数复杂度,增强函数的抗碰撞性,支持函数输出多种长度;设计一个明文预处理器,使用耦合映像格子产生与明文长度相关的混沌序列对明文进行填充,增强哈希函数抵抗长度扩展攻击的能力。仿真实验结果表明,提出的哈希函数效率优于SHA-2、SHA-3等的同类型混沌哈希函数,能够抵御第二原像攻击、多碰撞攻击和差分攻击等多种攻击方式,同时具有更好的抗碰撞性和映射均匀性。此外,提出的哈希函数可以输出不同长度的散列值,能够较好地应用在数字签名、密钥生成、基于哈希的消息认证码、确定性随机比特发生器等领域。
In recent years,widely used hash algorithms such as MD5 and SHA-1 have been found to have varying degrees of security risks.The iterative structure of the SHA-2 algorithm is similar to that of SHA-1,making it vulnerable to attacks as well.Meanwhile,SHA-3 has a complex internal structure and low implementation efficiency.To address these issues,a keyed hash function was designed and implemented based on chaotic neural network and C-MD structure.The approach involved improving the Merkle-Damgard structure by proposing the chaotic neural network Merkle-Damgard (C-MD) structure.This structure can be used to design a hash function that can withstand attacks such as the middle attack,multiple collision attack,and second pre-image attack for long information.Besides,the chaotic neural network was used as the compression function to increase the complexity of the hash function and improve its collision resistance,while also enabling it to output multiple lengths.Moreover,a plaintext preprocessor was designed,which used the coupled image lattice to generate chaos sequence related to the length of the plaintext to fill the plaintext,thus enhancing the ability of the hash function to resist length expansion attacks.Simulation results demonstrate that the proposed hash function performs faster than SHA-2,SHA-3 and the same type of chaotic hash function proposed by Teh et al.It can resist second pre-image attack,multi-collision attack and differential attack,while also exhibiting better collision resistance and mapping uniformity.In addition,the proposed Hash function can output Hash values of different lengths,making it suitable for use in digital signature,key generation,Hash-based message authentication code,deterministic random bit generator,and other application fields.
作者
陈立全
朱宇航
王宇
秦中元
马旸
CHEN Liquan;ZHU Yuhang;WANG Yu;QIN Zhongyuan;MA Yang(School of Cyber Science and Engineering,Southeast University,Nanjing 210096,China;Purple Mountain Laboratories for Network and Communication Security,Nanjing 211111,China)
出处
《网络与信息安全学报》
2023年第3期1-15,共15页
Chinese Journal of Network and Information Security
基金
国家重点研发计划(2020YFE0200600)。
