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Differential-Linear Attacks on Ballet Block Cipher
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作者 ZHOU Yu CHEN Si-Wei +2 位作者 XU Sheng-Yuan XIANG Ze-Jun ZENG Xiang-Yong 《密码学报(中英文)》 北大核心 2025年第2期469-488,共20页
Ballet is one of the finalists of the block cipher project in the 2019 National Cryptographic Algorithm Design Competition.This study aims to conduct a comprehensive security evaluation of Ballet from the perspective ... Ballet is one of the finalists of the block cipher project in the 2019 National Cryptographic Algorithm Design Competition.This study aims to conduct a comprehensive security evaluation of Ballet from the perspective of differential-linear(DL)cryptanalysis.Specifically,we present an automated search for the DL distinguishers of Ballet based on MILP/MIQCP.For the versions with block sizes of 128 and 256 bits,we obtain 16 and 22 rounds distinguishers with estimated correlations of 2^(-59.89)and 2^(-116.80),both of which are the publicly longest distinguishers.In addition,this study incorporates the complexity information of key-recovery attacks into the automated model,to search for the optimal key-recovery attack structures based on DL distinguishers.As a result,we mount the key-recovery attacks on 16-round Ballet-128/128,17-round Ballet-128/256,and 21-round Ballet-256/256.The data/time complexities for these attacks are 2^(108.36)/2^(120.36),2^(115.90)/2^(192),and 2^(227.62)/2^(240.67),respectively. 展开更多
关键词 Ballet block cipher differential-linear(DL)cryptanalysis MILP/MIQCP distinguisher key-recovery attacks
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A FRAMEWORK FOR REAL-VALUED CIPHER SYSTEMS
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作者 Zhaozhi ZHANG Nan JIANG 《Journal of Systems Science & Complexity》 SCIE EI CSCD 2007年第4期486-491,共6页
Most cipher systems designed thus far are binary-valued or integer-valued cipher systems. Their security relies on the assumption that one-way functions exist. Though the existence of one-way functions has not been pr... Most cipher systems designed thus far are binary-valued or integer-valued cipher systems. Their security relies on the assumption that one-way functions exist. Though the existence of one-way functions has not been proved yet, most cryptographic researchers believe that one-way functions exist. In addition, many candidates for one-way functions have been proposed. Therefore, the key step for developing real-valued cipher systems is to define real one-way functions and to propose candidates for them. In this paper, based on computational complexity theory over the real field, we give two definitions of real one-way functions; one is for digital one-way functions and the other is for general one-way functions. Candidates for these two classes of one-way functions are also proposed. Moreover, we present two examples to demonstrate that the candidates for both digital one-way functions and general one-way functions can be applied to construct secure real-valued cipher systems. 展开更多
关键词 Computational complexity theory digital one-way function general one-way function real-valued cipher system.
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NEURAL NETWORK MODELS FOR DESIGN OF BLOCK CIPHER SYSTEM
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作者 LUO Yuan(Department Of Mathematics, Nankai University, Tiajin 300071, China)ZHANG Zhaozhi(Institute of Systems Science, Academia Silica, Beijing 100080, China) 《Systems Science and Mathematical Sciences》 SCIE EI CSCD 1998年第2期161-167,共7页
In this paper, a class of block cipher systems having asymptotically perfectsecrecy is constructed by using the neural network models modified from the Hopfieldmodel.
关键词 Block cipher system HOPFIELD neural network ASYMPTOTICALLY PERFECT secrecy.
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Physical Layer Encryption of OFDM-PON Based on Quantum Noise Stream Cipher with Polar Code 被引量:2
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作者 Xu Yinbo Gao Mingyi +3 位作者 Zhu Huaqing Chen Bowen Xiang Lian Shen Gangxiang 《China Communications》 SCIE CSCD 2024年第3期174-188,共15页
Orthogonal frequency division multiplexing passive optical network(OFDM-PON) has superior anti-dispersion property to operate in the C-band of fiber for increased optical power budget. However,the downlink broadcast e... Orthogonal frequency division multiplexing passive optical network(OFDM-PON) has superior anti-dispersion property to operate in the C-band of fiber for increased optical power budget. However,the downlink broadcast exposes the physical layer vulnerable to the threat of illegal eavesdropping. Quantum noise stream cipher(QNSC) is a classic physical layer encryption method and well compatible with the OFDM-PON. Meanwhile, it is indispensable to exploit forward error correction(FEC) to control errors in data transmission. However, when QNSC and FEC are jointly coded, the redundant information becomes heavier and thus the code rate of the transmitted signal will be largely reduced. In this work, we propose a physical layer encryption scheme based on polar-code-assisted QNSC. In order to improve the code rate and security of the transmitted signal, we exploit chaotic sequences to yield the redundant bits and utilize the redundant information of the polar code to generate the higher-order encrypted signal in the QNSC scheme with the operation of the interleaver.We experimentally demonstrate the encrypted 16/64-QAM, 16/256-QAM, 16/1024-QAM, 16/4096-QAM QNSC signals transmitted over 30-km standard single mode fiber. For the transmitted 16/4096-QAM QNSC signal, compared with the conventional QNSC method, the proposed method increases the code rate from 0.1 to 0.32 with enhanced security. 展开更多
关键词 physical layer encryption polar code quantum noise stream cipher
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General Method of Combining Grover and Simon for Attacking Block Ciphers 被引量:1
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作者 Fu Xiangqun Bao Wansu +1 位作者 Shi Jianhong Li Tan 《China Communications》 SCIE CSCD 2024年第6期237-245,共9页
The compatibility of different quantum algorithms should be considered when these algorithms are combined.In this paper,the method of combining Grover and Simon is studied for the first time,under some preconditions o... The compatibility of different quantum algorithms should be considered when these algorithms are combined.In this paper,the method of combining Grover and Simon is studied for the first time,under some preconditions or assumptions.First,we give two preconditions of applying Grover’s algorithm,which ensure that the success probability of finding the marked element is close to 1.Then,based on these two preconditions,it is found out that the success probability of the quantum algorithm for FXconstruction is far less than 1.Furthermore,we give the design method of the Oracle function,and then present the general method of combining Grover and Simon algorithm for attacking block ciphers,with success probability close to 1. 展开更多
关键词 block ciphers post-quantum crypto quantum algorithms
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A Block Cipher Algorithm Based on Magic Square for Secure E-bank Systems
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作者 Farah Tawfiq Abdul Hussien Abdul Monem S.Rahma Hala Bahjat Abdul Wahab 《Computers, Materials & Continua》 SCIE EI 2022年第10期1329-1346,共18页
Nowadays the E-bank systems witnessed huge growth due to the huge developments in the internet and technologies.The transmitted information represents crucial information that is exposed to various kinds of attacks.Th... Nowadays the E-bank systems witnessed huge growth due to the huge developments in the internet and technologies.The transmitted information represents crucial information that is exposed to various kinds of attacks.This paper presents a new block cipher technique to provide security to the transmitted information between the customers and the ebank systems.The proposed algorithm consists of 10 rounds,each round involves 5 operations.The operations involve Add round key,Sub bytes,Zigzag method,convert to vector,and Magic Square of order 11.The purpose of this algorithm is to make use of the complexity of the Magic Square algorithm,the speed of addition operation,the confusion provided by the zigzag,using these operations with Galois field 28 GF(28),and repeating these operations for several rounds to build fast high secure encryption algorithm.This algorithm is designed to provide fast with high complexity and security which is suitable to encrypt the data that is transmitted over the internet.Speed,complexity,and The National Institute of Standards and Technology Framework NIST suite tests were done.The complexity of the proposed algorithm is=((256)32)r+1∗((256)89)r+1+(256)121.The proposed technique gives higher speed and security in the encryption and decryption phases,according to the results of the experiments.The degree of randomness has grown by 31.8 percent.Due to a decrease in the time of encrypting and decrypting,as well as the usage of the central processing unit(CPU),efficiency is improved.The encryption process throughput is enhanced by 13%,while the decryption process throughput is increased by 11.6 percent with the recommended approach. 展开更多
关键词 Block cipher magic square order 11 COMPLEXITY NIST suite ZIGZAG GF(28) MS11
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An Improved Framework of Massive Superpoly Recovery in Cube Attacks Against NFSR-Based Stream Ciphers
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作者 LIU Chen TIAN Tian QI Wen-Feng 《密码学报(中英文)》 CSCD 北大核心 2024年第5期1179-1198,共20页
A critical problem in the cube attack is how to recover superpolies efficiently.As the targeting number of rounds of an iterative stream cipher increases,the scale of its superpolies becomes larger and larger.Recently... A critical problem in the cube attack is how to recover superpolies efficiently.As the targeting number of rounds of an iterative stream cipher increases,the scale of its superpolies becomes larger and larger.Recently,to recover massive superpolies,the nested monomial prediction technique,the algorithm based on the divide-and-conquer strategy,and stretching cube attacks were proposed,which have been used to recover a superpoly with over ten million monomials for the NFSR-based stream ciphers such as Trivium and Grain-128AEAD.Nevertheless,when these methods are used to recover superpolies,many invalid calculations are performed,which makes recovering superpolies more difficult.This study finds an interesting observation that can be used to improve the above methods.Based on the observation,a new method is proposed to avoid a part of invalid calculations during the process of recovering superpolies.Then,the new method is applied to the nested monomial prediction technique and an improved superpoly recovery framework is presented.To verify the effectiveness of the proposed scheme,the improved framework is applied to 844-and 846-round Trivium and the exact ANFs of the superpolies is obtained with over one hundred million monomials,showing the improved superpoly recovery technique is powerful.Besides,extensive experiments on other scaled-down variants of NFSR-based stream ciphers show that the proposed scheme indeed could be more efficient on the superpoly recovery against NFSR-based stream ciphers. 展开更多
关键词 NFSR-based stream ciphers cube attacks MILP Trivium
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S盒密码学指标自动评估系统设计与实现
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作者 冷永清 敖天勇 +2 位作者 邱昕 崔兴利 李邵石 《信息网络安全》 北大核心 2025年第7期1103-1110,共8页
针对分组密码核心部件S盒的密码学指标计算繁琐、低效且缺乏便捷的评估软件问题,文章提出一种S盒多项密码学指标的计算方法及快速求解算法和一种S盒分量布尔函数的代数正规型形式快速求解算法。基于这些计算方法,利用MFC/C++编程技术,... 针对分组密码核心部件S盒的密码学指标计算繁琐、低效且缺乏便捷的评估软件问题,文章提出一种S盒多项密码学指标的计算方法及快速求解算法和一种S盒分量布尔函数的代数正规型形式快速求解算法。基于这些计算方法,利用MFC/C++编程技术,文章设计并实现了一套S盒密码学指标快速评估软件。该软件能够自动计算S盒的非线性度、线性逼近优势、差分均匀性、代数次数、代数项数分布、雪崩特性、扩散特性、不动点个数等多项密码学指标,具有操作简便、评估全面等优点,能够有效减少评估S盒的工作量。 展开更多
关键词 信息安全 分组密码 S盒 密码学指标 评估系统
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基于改进分段Logistic映射的PRNG算法
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作者 华漫 李锦长 李燕玲 《计算机与现代化》 2025年第3期113-118,126,共7页
分段Logistic映射的提出改善了经典Logistic映射的一些缺点,由于其复杂性高、安全性好等特点为混沌流密码设计领域提供了一种新的研究课题。为了改善分段Logistic混沌映射存在混沌序列均匀分布特性较差、密钥空间过小等安全隐患,提出一... 分段Logistic映射的提出改善了经典Logistic映射的一些缺点,由于其复杂性高、安全性好等特点为混沌流密码设计领域提供了一种新的研究课题。为了改善分段Logistic混沌映射存在混沌序列均匀分布特性较差、密钥空间过小等安全隐患,提出一种基于初始值和控制参数反馈调整的分段Logistic映射改进方法。该方法通过引入动态系统参数映射函数使输出的状态值分布的概率密度更均匀。基于优化后的分段Logistic混沌映射重新设计PRNG算法和分析比特级数字图像加密实验。实验结果表明本文算法产生的序列混沌特性更显著,分布更均匀,且具有更好的随机性,在流密码算法设计中具有广泛的应用前景。 展开更多
关键词 混沌系统 流密码 分段Logistic映射 图像加密 PRNG
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Quantum Circuit Implementation and Resource Evaluation of Ballet‑p/k Under Grover’s Attack
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作者 HONG Rui-Peng ZHANG Lei +3 位作者 PANG Chen-Xu LI Guo-Yuan DING Ding WANG Jian-Xin 《密码学报(中英文)》 北大核心 2025年第5期1178-1194,共17页
The advent of Grover’s algorithm presents a significant threat to classical block cipher security,spurring research into post-quantum secure cipher design.This study engineers quantum circuit implementations for thre... The advent of Grover’s algorithm presents a significant threat to classical block cipher security,spurring research into post-quantum secure cipher design.This study engineers quantum circuit implementations for three versions of the Ballet family block ciphers.The Ballet‑p/k includes a modular-addition operation uncommon in lightweight block ciphers.Quantum ripple-carry adder is implemented for both“32+32”and“64+64”scale to support this operation.Subsequently,qubits,quantum gates count,and quantum circuit depth of three versions of Ballet algorithm are systematically evaluated under quantum computing model,and key recovery attack circuits are constructed based on Grover’s algorithm against each version.The comprehensive analysis shows:Ballet-128/128 fails to NIST Level 1 security,while when the resource accounting is restricted to the Clifford gates and T gates set for the Ballet-128/256 and Ballet-256/256 quantum circuits,the design attains Level 3. 展开更多
关键词 Grover’s algorithm quantum circuit Ballet family block ciphers quantum ripple-carry adder
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巧用Cipher命令指定修复代理人
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作者 李翠平 《科技创新导报》 2008年第6期175-175,177,共2页
本文介绍了使用cipher命令,简单快速创建EFS的修复代理人的方法。其中修复代理人的指定涉及到了服务器中用户权限的升级问题,以及在服务器中关于组策略的具体使用。这些方法的使用保证了cipher命令产生的密钥能被顺利运用。
关键词 cipher 修复代理人 加密 解密
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Differential Collision Attack on Reduced FOX Block Cipher 被引量:5
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作者 Chen Jie Hu Yupu +1 位作者 Zhang Yueyu Dong Xiaoli 《China Communications》 SCIE CSCD 2012年第7期71-76,共6页
This paper presents a method for differen- tial collision attack of reduced FOX block cipher based on 4-round distinguishing property. It can be used to attack 5, 6 and 7-round FOX64 and 5-round FOX128. Our attack has... This paper presents a method for differen- tial collision attack of reduced FOX block cipher based on 4-round distinguishing property. It can be used to attack 5, 6 and 7-round FOX64 and 5-round FOX128. Our attack has a precomputation phase, but it can be obtained before attack and computed once for all. This attack on the reduced to 4-round FOX64 requires only 7 chosen plaintexts, and performs 242.8 4-round FOX64 encryptions. It could be extended to 5 (6, 7)-round FOX64 by a key exhaustive search behind the fourth round. 展开更多
关键词 CRYPTOGRAPHY block cipher FOX differential collision attack
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Improved Feistel-based ciphers for wireless sensor network security 被引量:3
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作者 Tamara PAZYNYUK George S. OREKU 《Journal of Zhejiang University-Science A(Applied Physics & Engineering)》 SCIE EI CAS CSCD 2008年第8期1111-1117,共7页
Wireless sensor networks (WSNs) are exposed to a variety of attacks. The quality and complexity of attacks are rising day by day. The proposed work aims at showing how the complexity of modern attacks is growing accor... Wireless sensor networks (WSNs) are exposed to a variety of attacks. The quality and complexity of attacks are rising day by day. The proposed work aims at showing how the complexity of modern attacks is growing accordingly, leading to a similar rise in methods of resistance. Limitations in computational and battery power in sensor nodes are constraints on the diversity of security mechanisms. We must apply only suitable mechanisms to WSN where our approach was motivated by the application of an improved Feistel scheme. The modified accelerated-cipher design uses data-dependent permutations, and can be used for fast hardware, firmware, software and WSN encryption systems. The approach presented showed that ciphers using this approach are less likely to suffer intrusion of differential cryptanalysis than currently used popular WSN ciphers like DES, Camellia and so on. 展开更多
关键词 SECURITY cipher Wireless sensor network (WSN) Feistel scheme
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Automatic Search of Impossible Differentials and Zero-Correlation Linear Hulls for ARX Ciphers 被引量:5
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作者 Kai Zhang Jie Guan Bin Hu 《China Communications》 SCIE CSCD 2018年第2期54-66,共13页
In lightweight cryptographic primitives, round functions with only simple operations XOR, modular addition and rotation are widely used nowadays. This kind of ciphers is called ARX ciphers. For ARX ciphers, impossible... In lightweight cryptographic primitives, round functions with only simple operations XOR, modular addition and rotation are widely used nowadays. This kind of ciphers is called ARX ciphers. For ARX ciphers, impossible differential cryptanalysis and zero-correlation linear cryptanalysis are among the most powerful attacks, and the key problems for these two attacks are discovering more and longer impossible differentials(IDs) and zero-correlation linear hulls(ZCLHs). However, finding new IDs and ZCLHs for ARX ciphers has been a manual work for a long time, which has been an obstacle in improving these two attacks. This paper proposes an automatic search method to improve the efficiency of finding new IDs and ZCLHs for ARX ciphers. In order to prove the efficiency of this new tool, we take HIGHT, LEA, SPECK three typical ARX algorithms as examples to explore their longer and new impossible differentials and zero-correlation linear hulls. To the best of our knowledge, this is the first application of automatic search method for ARX ciphers on finding new IDs and ZCLHs. For HIGHT, we find more 17 round IDs and multiple 17 round ZCLHs. This is the first discovery of 17 round ZCLHs for HIGHT. For LEA, we find extra four 10 round IDs and several 9 round ZCLHs. In the specification of LEA, the designers just identified three 10 round IDs and one 7round ZCLH. For SPECK, we find thousands of 6 round IDs and forty-four 6 round ZCLHs. Neither IDs nor ZCLHs of SPECK has been proposed before. The successful application of our new tool shows great potential in improving the impossible differential cryptanalysis and zero-correlation linear cryptanalysis on ARX ciphers.. 展开更多
关键词 automatic search tool impossibledifferential cryptanalysis zero-correlation lin-ear cryptanalysis ARX ciphers modes opera-tion
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Fault-Propagate Pattern Based DFA on PRESENT and PRINTcipher 被引量:2
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作者 ZHAO Xinjie GUO Shize +2 位作者 WANG Tao ZHANG Fan SHI Zhijie 《Wuhan University Journal of Natural Sciences》 CAS 2012年第6期485-493,共9页
This article proposes an enhanced differential fault analysis(DFA) method named as fault-propagation pattern-based DFA(FPP-DFA).The main idea of FPP-DFA is using the FPP of the ciphertext difference to predict the... This article proposes an enhanced differential fault analysis(DFA) method named as fault-propagation pattern-based DFA(FPP-DFA).The main idea of FPP-DFA is using the FPP of the ciphertext difference to predict the fault location and the fault-propagation path.It shows that FPP-DFA is very effective on SPN structure block ciphers using bitwise permutation,which is applied to two block ciphers.The first is PRESENT with the substitution permutation sequence.With the fault model of injecting one nibble fault into the r-2nd round,on average 8 and 16 faults can reduce the key search space of PRESENT-80/128 to 214.7 and 221.1,respectively.The second is PRINTcipher with the permutation substitution sequence.For the first time,it shows that although the permutation of PRINTcipher is secret key dependent,FPP-DFA still works well on it.With the fault model of injecting one nibble fault into the r-2nd round,12 and 24 effective faults can reduce the key search space of PRINTcipher-48/96 to 213.7 and 222.8,respectively. 展开更多
关键词 fault-propagation pattern differential fault analysis bitwise permutation SPN block cipher PRESENT PRINTcipher
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Secure Video Streaming with Lightweight Cipher PRESENT in an SDN Testbed 被引量:2
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作者 Pengcheng Liu Xiaojun Wang +3 位作者 S.R.Chaudhry Khalid Javeed Yue Ma Martin Collier 《Computers, Materials & Continua》 SCIE EI 2018年第12期353-363,共11页
The combination of traditional processors and Field Programmable Gate Arrays(FPGA)is shaping the future networking platform for intensive computation in resource-constrained networks and devices.These networks present... The combination of traditional processors and Field Programmable Gate Arrays(FPGA)is shaping the future networking platform for intensive computation in resource-constrained networks and devices.These networks present two key challenges of security and resource limitations.Lightweight ciphers are suitable to provide data security in such constrained environments.Implementing the lightweight PRESENT encryption algorithm in a reconfigurable platform(FPGAs)can offer secure communication service and flexibility.This paper presents hardware acceleration of security primitives in SDN using NETFPGA-10G.We implement an efficient design of the PRESENT algorithm for faster,smaller and lower power consumption hardware circuit using Verilog.We evaluate the performance of the hardware and software implementations of PRESENT.Experimental results prove that the proposed hardware design is a viable option for use in resource constrained devices in future networks and their applications. 展开更多
关键词 Lightweight cipher NETFPGA openFlow RESENT encryption
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A fast image encryption algorithm based on only blocks in cipher text 被引量:2
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作者 王兴元 王倩 《Chinese Physics B》 SCIE EI CAS CSCD 2014年第3期165-172,共8页
In this paper, a fast image encryption algorithm is proposed, in which the shuffling and diffusion is performed simul- taneously. The cipher-text image is divided into blocks and each block has k x k pixels, while the... In this paper, a fast image encryption algorithm is proposed, in which the shuffling and diffusion is performed simul- taneously. The cipher-text image is divided into blocks and each block has k x k pixels, while the pixels of the plain-text are scanned one by one. Four logistic maps are used to generate the encryption key stream and the new place in the cipher image of plain image pixels, including the row and column of the block which the pixel belongs to and the place where the pixel would be placed in the block. After encrypting each pixel, the initial conditions of logistic maps would be changed ac- cording to the encrypted pixel's value; after encrypting each row of plain image, the initial condition would also be changed by the skew tent map. At last, it is illustrated that this algorithm has a faster speed, big key space, and better properties in withstanding differential attacks, statistical analysis, known plaintext, and chosen plaintext attacks. 展开更多
关键词 image encryption shuffle and diffuse simultaneously block cipher logistic map
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Differential Fault Analysis and Meet-in-the-Middle Attack on the Block Cipher KATAN32 被引量:1
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作者 张文英 刘枫 +1 位作者 刘宣 孟帅 《Journal of Shanghai Jiaotong university(Science)》 EI 2013年第2期147-152,共6页
We investigate the lightweight block cipher KATAN family which consists of three variants with 32, 48 and 64-bit block sizes, called KATAN32, KATAN48 and KATAN64 respectively. However, three variants all have the same... We investigate the lightweight block cipher KATAN family which consists of three variants with 32, 48 and 64-bit block sizes, called KATAN32, KATAN48 and KATAN64 respectively. However, three variants all have the same key length of 80 bits. On the basis of the bit-oriented faulty model and the differential analysis principle, we describe the attack that combines differential fault attack with the meet-in-the-middle (MITM) attack on the KATAN32. More precisely, inducing a fault at a bit, we can recover some linear differential fault equations on the key bits. During solving equations, without the help of computer, we need only algebraic deduction to obtain relations of some key bits. The complexity in this process is neglectable. The secret key of the full cipher can be recovered faster than exhaustive search for all three block sizes in the KATAN family. Our result describes that KATAN32 is vulnerable. 展开更多
关键词 KATAN32 DIFFERENTIAL FAULT analysis meet-in-the-middle (MITM) ATTACK BLOCK cipher LIGHTWEIGHT cipher
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How to repair the Hill cipher 被引量:1
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作者 ISMAIL I.A. AMIN Mohammed DIAB Hossam 《Journal of Zhejiang University-Science A(Applied Physics & Engineering)》 SCIE EI CAS CSCD 2006年第12期2022-2030,共9页
The Hill cipher algorithm is one of the symmetric key algorithms that have several advantages in data encryption. However, a main drawback of this algorithm is that it encrypts identical plaintext blocks to identical ... The Hill cipher algorithm is one of the symmetric key algorithms that have several advantages in data encryption. However, a main drawback of this algorithm is that it encrypts identical plaintext blocks to identical ciphertext blocks and cannot encrypt images that contain large areas of a single color. Thus, it does not hide all features of the image which reveals patterns in the plaintext. Moreover, it can be easily broken with a known plaintext attack revealing weak security. This paper presents a variant of the Hill cipher that overcomes these disadvantages. The proposed technique adjusts the encryption key to form a dif- ferent key for each block encryption. Visually and computationally, experimental results demonstrate that the proposed variant yields higher security and significantly superior encryption quality compared to the original one. 展开更多
关键词 Hill cipher Image encryption Modified Hill cipher Quality of encryption
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Security Analysis and Enhanced Design of a Dynamic Block Cipher 被引量:4
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作者 ZHAO Guosheng WANG Jian 《China Communications》 SCIE CSCD 2016年第1期150-160,共11页
There are a lot of security issues in block cipher algorithm.Security analysis and enhanced design of a dynamic block cipher was proposed.Firstly,the safety of ciphertext was enhanced based on confusion substitution o... There are a lot of security issues in block cipher algorithm.Security analysis and enhanced design of a dynamic block cipher was proposed.Firstly,the safety of ciphertext was enhanced based on confusion substitution of S-box,thus disordering the internal structure of data blocks by four steps of matrix transformation.Then,the diffusivity of ciphertext was obtained by cyclic displacement of bytes using column ambiguity function.The dynamic key was finally generated by using LFSR,which improved the stochastic characters of secret key in each of round of iteration.The safety performance of proposed algorithm was analyzed by simulation test.The results showed the proposed algorithm has a little effect on the speed of encryption and decryption while enhancing the security.Meanwhile,the proposed algorithm has highly scalability,the dimension of S-box and the number of register can be dynamically extended according to the security requirement. 展开更多
关键词 cryptography block cipher encryption algorithm safety analysis
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