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Evaluate the security margins of sha-512, sha-256and DHA-256 against the boomerang attack

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Science China(Information Sciences) 2016年第5期59卷 144-157页

作者： Hongbo YU Yonglin HAO Dongxia BAI Department of Computer Science and Technology Tsinghua Universtiy

For an n-bit random permutation, there are three types of boomerang distinguishers, denoted as Type I, II and III, with generic complexities 2~n, 2n/3and 2n/2respectively. In this paper, we try to evaluate the security margins of three hash functions namely sha-512, sha-256 and DHA-256 against the boomerang ***, we give a boomerang attack on 48-step sha-512 with a practical complexity of 251. The correctness of this attack is verified by providing a Type III boomerang quartet. Then, we extend the existing differential characteristics of the three hash functions to more rounds. We deduce the sufficient conditions and give thorough evaluations to the security margins as follows: Type I boomerang method can attack 54-step sha-512, 51-step sha-256 and 46-step DHA-256 with complexities 2480, 2218and 2236respectively. Type II boomerang method can attack 51-step sha-512, 49-step sha-256 and 43-step DHA-256 with complexities 2158.50, 272.91and 274.50respectively. Type III boomerang method can attack 52-step sha-512, 50-step sha-256 and 44-step DHA-256 with complexities 2223.80, 2123.63and 299.85respectively.

关键词： sha-512 sha-256 DHA-256 hash functions boomerang attack

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单向散列函数sha-512的优化设计

计算机工程 2007年第7期33卷 130-132,165页

作者：李鸿强苗长云石博雅仪鲁男天津工业大学信息与通信工程学院天津300160 北京邮电大学软件学院北京102209

在分析NIST的散列函数sha-512基础上,对散列函数sha-512中的关键运算部分进行了分解,通过采用中间变量进行预行计算,达到了sha-512中迭代部分的并行计算处理,提高了运算速度。通过这种新的硬件结构,优化后的散列函数sha-512在71.5MHz时... 详细信息

在分析NIST的散列函数sha-512基础上,对散列函数sha-512中的关键运算部分进行了分解,通过采用中间变量进行预行计算,达到了sha-512中迭代部分的并行计算处理,提高了运算速度。通过这种新的硬件结构,优化后的散列函数sha-512在71.5MHz时钟频率下性能达到了1652Mbit/s的数据吞吐量,比优化前性能提高了约2倍,最后还将实验结果与MD-5、sha-1商用IP核性能进行了比较。

关键词：单向散列函数 sha—1 sha-512

sha-512算法及其基于生日攻击的安全性分析

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后勤工程学院学报 2010年第3期26卷 92-96页

作者：刘美王玉柱何定养郑贤路后勤工程学院后勤信息工程系

生日攻击是一种通用的碰撞攻击方法,它可用于攻击任何类型的散列函数。分析了sha-512的算法原理,讨论了生日攻击的碰撞阈值和攻击步骤,并对sha-512算法在生日攻击下的安全性进行了分析。通过分析得出sha-512所有消息块处理完后得到了8... 详细信息

生日攻击是一种通用的碰撞攻击方法,它可用于攻击任何类型的散列函数。分析了sha-512的算法原理,讨论了生日攻击的碰撞阈值和攻击步骤,并对sha-512算法在生日攻击下的安全性进行了分析。通过分析得出sha-512所有消息块处理完后得到了8个64位变量H0-H7的数据级联,并且输出散列码是512位,这对于攻击者来说是不可预测的,猜中的概率可以忽略,而找到目标消息的碰撞的计算复杂度为2256。所以,相对来说sha-512的安全性比MD5,sha-1等要高,采用sha-512后将更能抵抗生日攻击,并能抵御已知密码分析攻击。

关键词： sha-512 散列函数生日攻击安全性

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基于sha-512的文件损毁检测系统

电子技术与软件工程 2021年第6期 209-211页

作者：李若曦华东理工大学上海市200237

本文讲述sha-512算法的工作原理及其应用实现验证数字完整性系统。安全哈希算法(Secure Hash Algorithm)主要适用于数字签名标准里面定义的数字签名算法。sha-512是接收一段长度小于2128位的消息,然后以一种不可逆的方式将它转化为长度... 详细信息

本文讲述sha-512算法的工作原理及其应用实现验证数字完整性系统。安全哈希算法(Secure Hash Algorithm)主要适用于数字签名标准里面定义的数字签名算法。sha-512是接收一段长度小于2128位的消息,然后以一种不可逆的方式将它转化为长度固定为512位的散列值(也称为信息摘要)。散列函数值可以说是对明文的一种“指纹”。

关键词： sha-512 哈希算法检测系统文件损毁

一种基于FPGA的sha-512算法高速实现

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信息工程大学学报 2008年第1期9卷 94-96页

作者：光焱祝跃飞吴树华姚刚信息工程大学信息工程学院河南郑州450002

研究了一种新的sha-512算法基于FPGA的高速实现方案。为了获得较高的加密处理速度,本方案在关键计算路径上进行了加法器结构的优化;并且实现了分组数据输入与循环运算的并行进行,减少了加密一个分组所需的时钟周期数,提高了加密效率。在... 详细信息

研究了一种新的sha-512算法基于FPGA的高速实现方案。为了获得较高的加密处理速度,本方案在关键计算路径上进行了加法器结构的优化;并且实现了分组数据输入与循环运算的并行进行,减少了加密一个分组所需的时钟周期数,提高了加密效率。在FPGA器件上实际运行,芯片工作在103 Mhz的时钟频率下,数据处理速率达到1300 Mbits/sec。

关键词： sha-512 FPGA 硬件描述语言加法器

Secured Access Policy in Ciphertext-Policy Attribute-Based Encryption for Cloud Environment

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Computer Systems Science & Engineering 2023年第7期46卷 1079-1092页

作者： P.Prathap Nayudu Krovi Raja Sekhar Department of Computer Science and Engineering Koneru Lakshmaiah Education Foundation VaddeswaramAPIndia

The cloud allows clients to store and share *** on the user’s needs,it is imperative to design an effective access control plan to share the information only with approved *** user loses control of their data when the data is outsourced to the ***,access control mechanisms will become a significant challenging *** Ciphertext-Policy Attribute-Based Encryption(CP-ABE)is an essential solution in which the user can control data ***-ABE encrypts the data under a limited access policy after the user sets some access *** user can decrypt the data if they satisfy the limited access *** CP-ABE is an effective access control program,the privacy of the policy might be compromised by the ***,the attackers can gather important information from plain text *** address this issue,the sha-512 algorithm is presented to create a hash code for the user’s attributes in this *** on the created hash codes,an access policy will be *** leads to protecting the access policy against *** effectiveness of the proposed scheme is assessed based on decryption time,private key generation time,ciphertext generation time,and data verification time.

关键词： Cloud computing access policy CP-ABE hash code sha-512 attribute ciphertext encryption decryption

Wi-Fi: WPA2 Security Vulnerability and Solutions

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Wireless Engineering and Technology 2021年第2期12卷 15-22页

作者： Zahoor Ahmad Najar Roohe Naaz Mir Deaprtment of IT Central University of Kashmir Srinagar India Department of Computer Science and Engineering National Institute of Technology Srinagar India

The Internet of Things (IoT) is an emerging network infrastructure with more than five devices owned by a single user. Wireless connectivity forms the backbone of such infrastructure. IoT uses diverse wireless communication technologies such as IEEE 802.15.4, Wi-Fi, Zigbee, Bluetooth, RFID, BLE (Bluetooth Low Energy), and various other cellular technologies. Wi-Fi is most suitable for IoT Home or office networks. Practically wireless signals do not adhere to the boundaries of the office or home, or organization and impose inherent security risks like information leakage, unauthorized access, other security and privacy threats to networking infrastructure. Therefore Authorization/Association of devices is one of the main security concerns. This paper discusses how unauthorized access to wireless networks (Wi-Fi) can be secured by improving existing WPA2 protocol security.

关键词： Wi-Fi WPA2 sha-512 IoT

Simultaneous Hashing of Multiple Messages

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Journal of Information Security 2012年第4期3卷 319-325页

作者： shay Gueron Vlad Krasnov Department of Mathematics University of Haifa Haifa Israel Intel Corporation Israel Development Center Haifa Israel

We describe a method for efficiently hashing multiple messages of different lengths. Such computations occur in various scenarios, and one of them is when an operating system checks the integrity of its components during boot time. These tasks can gain performance by parallelizing the computations and using SIMD architectures. For such scenarios, we compare the performance of a new 4-buffers sha-256 S-HASH implementation, to that of the standard serial hashing. Our results are measured on the 2nd Generation Intel? CoreTM Processor, and demonstrate sha-256 processing at effectively ~5.2 Cycles per Byte, when hashing from any of the three cache levels, or from the system memory. This represents speedup by a factor of 3.42x compared to OpenSSL (1.0.1), and by 2.25x compared to the recent and faster n-SMS method. For hashing from a disk, we show an effective rate of ~6.73 Cycles/Byte, which is almost 3 times faster than OpenSSL (1.0.1) under the same conditions. These results indicate that for some usage models, sha-256 is significantly faster than commonly perceived.

关键词： sha-256 sha-512 sha3 Competition SIMD Architecture Advanced Vector Extensions Architectures AVX AVX2

Design and Development of a Novel Symmetric Algorithm for Enhancing Data Security in Cloud Computing

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Journal of Information Security 2019年第4期10卷 199-236页

作者： Mohammad Anwar Hossain Ahsan Ullah Newaz Ibrahim Khan Md Feroz Alam Department of Computer Science and Engineering World University of Bangladesh Dhaka Bangladesh

Cloud computing is a kind of computing that depends on shared figuring assets instead of having nearby servers or individual gadgets to deal with applications. Technology is moving to the cloud more and more. It’s not just a trend, the shift away from ancient package models to package as service has steadily gained momentum over the last ten years. Looking forward, the following decade of cloud computing guarantees significantly more approaches to work from anyplace, utilizing cell phones. Cloud computing focused on better performances, better scalability and resource consumption but it also has some security issue with the data stored in it. The proposed algorithm intents to come with some solutions that will reduce the security threats and ensure far better security to the data stored in cloud.

关键词： Data Security Cloud Computing Encryption Decryption Secret Key Symmetric Algorithm 192 Bits Hashing Permutation sha-512