AES算法的一种高效FPGA实现方法

在简要介绍AES算法(Rijndael)加密解密流程的基础上,结合该算法特点,采用复合域方法优化了S-Box的实现,并简化了MixColumns和InvMixColumns的结构,最后采用6级流水线在FPGA上加以高速高效实现.     

Low-power and area-optimized VLSI implementation of AES coprocessor for Zigbee system

A low-power and low-cost advanced encryption standard (AES) coprocessor is proposed for Zigbee system-on-a-chip (SoC) design. The cost and power consumption of the proposed AES coprocessor are reduced considerably by optimizing the architectures of SubBytes/InvSubBytes and MixColumns/InvMixColumns, integrating the encryption and deeryption procedures together by the method of resource sharing, and using the hierarchical power management strategy based on finite state machine (FSM) and clock gating (CG) technologies. Based on SMIC 0.18 μm complementary metal oxide semiconductor (CMOS) technology, the scale of the AES coprocessor is only about 10.5 kgate, the corresponding power consumption is 69.1 μW/MHz,and the throughput is 32 Mb/s, which is reasonable and sufficient for Zigbee system. Compared with other designs, the proposed architecture consumes less power and fewer hardware resources, which is conducive to the Zigbee system and other portable devices.     

基于FPGA硬件加密的设计与实现

以FPGA芯片Cyclone II系列为核心,构建FPGA硬件平台,提出一种以资源优先为目的的DES、AES加解密设计方案。通过分析S盒的非线性特征,构造新的复合域变换,避免因同构变换产生的资源损耗。加解密过程中利用轮函数硬件结构的复用,达到硬件资源占用的最小化。整体采用内嵌流水线结构,减少逻辑复杂度的同时提高处理速度。实验结果验证了FPGA硬件加密的资源占用率远低于ASIC的硬件加密,执行速度达到Gbit/s,加密性能大大提高。     

一种AES密码算法的硬件实现

介绍了一种适用于较小面积应用场合AES密码算法的实现方案。结合该算法的特点,在常规轮变换中提出一种加/解密列混合变换集成化的硬件结构设计,通过选择使用同一个模块,可以实现加密和解密中的线性变换,既整合了部分加/解密硬件结构,又节约了大量的硬件资源。仿真与综合结果表明,加/解密运算模块面积不超过25000个等效门,有效地减小了硬件实现面积,同时该设计方案也满足实际应用性能的需求。     

Memory-free low-cost designs of advanced encryption standard using common subexpression elimination for subfunctions in transformations

In this paper, we propose area-efficient Advanced Encryption Standard (AES) processor designs by applying a new common-subexpression-elimination (CSE) algorithm to the subfunctions that realize the various transformations in AES encryption and decryption. The first category of subfunctions is derived by combining adjacent transformations in each AES round into a new transformation. The other category of subfunctions is from the integrated transformations in the AES encryption and decryption process with shared common operations. Then the proposed bit-level CSE algorithm reduces further the area cost of realizing the subfunctions by extracting the common factors in the bit-level expressions of these subfunctions. The separate area-reduction effects of combinations, integrations, and CSE optimization mentioned above are analyzed in order to examine the efficiency of each technique. Cell-based implementation results show that the proposed AES designs can achieve am area reduction rate of about 20% compared with Synopsys optimization results.     

High-speed VLSI architectures for the AES algorithm

This paper presents novel high-speed architectures for the hardware implementation of the Advanced Encryption Standard (AES) algorithm. Unlike previous works which rely on look-up tables to implement the SubBytes and InvSubBytes transformations of the AES algorithm, the proposed design employs combinational logic only. As a direct consequence, the unbreakable delay incurred by look-up tables in the conventional approaches is eliminated, and the advantage of subpipelining can be further explored. Furthermore, composite field arithmetic is employed to reduce the area requirements, and different implementations for the inversion in subfield GF(2/sup 4/) are compared. In addition, an efficient key expansion architecture suitable for the subpipelined round units is also presented. Using the proposed architecture, a fully subpipelined encryptor with 7 substages in each round unit can achieve a throughput of 21.56 Gbps on a Xilinx XCV1000 e-8 bg560 device in non-feedback modes, which is faster and is 79% more efficient in terms of equivalent throughput/slice than the fastest previous FPGA implementation known to date.     

High Definition Image Encryption Algorithm Based on AES Modification

In this article, a high-speed and highly restricted encryption algorithm is proposed to cipher high-definition (HD) images based on the modified advanced encryption standard (AES) algorithm. AES is a well-known block cipher algorithm and has several advantages, such as high-level security and implementation ability. However, AES has some drawbacks, including high computation costs, pattern appearance, and high hardware requirements. The aforementioned problems become more complex when the AES algorithm ciphers an image, especially HD images. Three modifications are proposed in this paper to improve AES algorithm performance through, decreasing the computation costs, decreasing the hardware requirements, and increasing the security level. First, modification was conducted using MixColumn transformation in 5 rounds instead of 10 rounds in the original AES-128 to decrease the encryption time. Security is enhanced by improving the key schedule operation by adding MixColumn transformation to this operation as second modification. In addition, to decrease the hardware requirements, S-box and Inv. S-box in the original AES are replaced by one simple S-box used for encryption and decryption in the proposed method. The proposed AES version conducts one of the ciphering modes to solve the appearance pattern problem. Experimental results indicate that the proposed modifications to the AES algorithm made the algorithm more compatible with HD image encryption.     

基于低成本FPGA的AES密码算法设计

主要介绍在逻辑资源少的现场可编程门阵列（FPGA）上实现高级数据加密标准（AES）算法设计。首先描述了AES加密算法,并在FPGA上优化实现AES算法,设计结构采用多轮加密共用一个轮运算的顺序结构,加密和解密模块共用密钥扩展模块,减少资源占用,在低时钟频率下保持较高的性能。采用了16位的并行总线通信接口,利用先进先出缓冲器（FIFO）对输入输出数据进行缓存。最后通过仿真和实测表明,在50MHz时钟下加解密速率可达530Mb/s。     

基于AHB总线的AES密码协处理器实现

AES加密算法是一种的常规加密算法,其被广泛应用在商业和政府部门。本文研究了AES(Advanced Encryption Standard)算法,包括AES的具体加密、解密过程以及基于AMBA(高级微控制器总线架构)总线的硬件实现方法。本文还介绍了一种用仿真与采用Xilinx公司的Virtex-4 LX100 FPGA器件来快速验证AES算法硬件IP核的方法。     

基于改进AES加密算法的DICOM医学图像安全性研究

 本文基于AES算法的设计原理提出了一种改进的医学图像加密算法.针对AES算法结合斜帐篷映射对其进行改进,使其适合DICOM医学图像的数据特点.首先将AES中4*4的分块操作方式变成M*N的全图操作,其次增加了对病人基本信息的保护,最后改进了AES中列混合操作与密钥编排方式.通过理论分析与仿真实验证明改进算法具有较好的置乱效果、扩散性强,并且能够很好地保持DICOM文件格式的兼容性.     

面向HT的CCMP算法的面积优化实现方法

根据802.11i AES加密/解密算法的要求,配合给定的系统时钟频率,提出了较为节约面积的、极为规则的AES运算电路的实现方法.通过分析系统时钟与系统数据吞吐量的要求,给出了较为合理的面向HT(High Throughput)的802.11i CCMP AES算法系统架构,对其中的AES运算单元的实现方法进行分析比较,得出了较小面积的AES运算单元的实现方案.用Design Compiler做综合分析后发现,优化后的面积比现有的方法至少下降了31%,从而有效地降低了IC的成本.     

Rijndael FPGA Implementations Utilising Look-Up Tables

This paper presents single-chip FPGA Rijndael algorithm implementations of the Advanced Encryption Standard (AES) algorithm, Rijndael. In particular, the designs utilise look-up tables to implement the entire Rijndael Round function. A comparison is provided between these designs and similar existing implementations. Hardware implementations of encryption algorithms prove much faster than equivalent software implementations and since there is a need to perform encryption on data in real time, speed is very important. In particular, Field Programmable Gate Arrays (FPGAs) are well suited to encryption implementations due to their flexibility and an architecture, which can be exploited to accommodate typical encryption transformations. In this paper, a Look-Up Table (LUT) methodology is introduced where complex and slow operations are replaced by simple LUTs. A LUT-based fully pipelined Rijndael implementation is described which has a pre-placement performance of 12 Gbits/sec, which is a factor 1.2 times faster than an alternative design in which look-up tables are utilised to implement only one of the Round function transformations, and 6 times faster than other previous single-chip implementations. Iterative Rijndael implementations based on the Look-Up-Table design approach are also discussed and prove faster than typical iterative implementations.     

Magpie:一种高安全的轻量级分组密码算法

论文提出了一种新的高安全轻量级密码算法,命名为Magpie.Magpie是基于SPN结构,分组长度为64位,密钥长度为96位,包含32轮运算.Magpie密码算法包括两个部分:运算部分和控制部分.运算部分,每轮运算包括五个基本运算模块:常数加,S盒变换,行移位,列混合,轮密钥加.控制部分,将密钥的第65位到96位作为Magpie加密算法的控制信号,其中密钥第65位到第80位作为S盒变换控制信号,第81位到第96位值作为列混合,行移位变换和每轮运算的控制信号.在Xilinx Virtex-5 FPGA上实现面积仅为10679 Slices,加密速率为6.4869Gb/s.     

面向密码算法的异步可重构结构设计

针对FPGA和ASIC在实现密码算法时的不足之处，本文介绍了一种面向密码算法的异步可重构结构。该结构的运算功能由一个可重构单元阵列提供，数据通路由可重构单元之间的相互连接实现，异步通信采用握手信号完成。在分析握手信号传输延时对可重构结构的影响后，文章提出了一种适合该结构的单元信号传输握手控制电路。同时在单元结构中，使用改进的DSDCVS逻辑来设计其运算电路，减小了单元的面积，提高了单元的工作速度。应用实例表明，在实现密码算法时，面向密码算法的异步可重构结构表现出了比FPGA更好的性能。     

基于结构共享和多级流水线的AES算法硬件实现

针对AES算法,提出了一种新颖的AES算法的硬件实现.与传统的硬件实现方法不同,首先分析了AES算法的结构,并通过修改解密流程,在加解密流程中采用结构共享,节省了芯片的面积;其次在字节代换中采用了复合域中的运算,使得不可减小的时间延迟变得最小;最后通过仔细分析电路中各部分的时间延迟,采用8级流水线结构,最大程度地提高了数据处理的速度.文中提出的硬件结构适用于芯片面积资源紧张、芯片处理速度要求较快的场合.     

基于FPGA的AES算法的实现

介绍了高级加密标准( AES,Advanced Encryption Standard)算法的原理,设计了一个能够实现初始密钥128位、192位和256位可选的AES加解密算法系统,以适应多种使用环境.实验结果表明了基于现场可编程门阵列(FPGA)可编程逻辑器件的实现方法提供了并行处理能力,达到设计所要求的处理性能基准.整个设计具有很强的实用性,运行稳定,且效果良好,可以被广泛应用于网络,文件等安全系统.     

一种有效缩减AES算法S盒面积的组合逻辑优化设计

 通过对AES算法S盒构造原理的研究,利用其中仿射变换的系数具有循环移位的周期性特点对电路结构进行改进,提出一种面积优化的AES算法S盒组合逻辑电路设计方法。该方法基于流水线技术,采用倍频复用的电路结构,较传统结构减少了逻辑资源的使用。经过EDA工具综合仿真和实际系统验证,该方法比Wolkerstorfer和Satoh的S盒有限域实现的硬件规模分别缩减了47.53%和41.49%,比Morioka的S盒真值表实现的硬件规模缩减了21.43%。该设计方案已成功用于一种基于FPGA实现的密码专用处理器设计中。     

FPGA Implementation and Energy Cost Analysis of Two Light-Weight Involutional Block Ciphers Targeted to Wireless Sensor Networks

In this paper, we investigate the energy cost of the FPGA implementation of two cryptographic algorithms targeted to wireless sensor networks (WSNs). Recent trends have seen the emergence of WSNs using sensor nodes based on reconfigurable hardware, such as a field-programmable gate arrays (FPGAs), thereby providing flexible functionality with higher performance than classical microcontroller based sensor nodes. In our study, we investigate the hardware implementation of involutional block ciphers since the characteristics of involution enables performing encryption and decryption using the same circuit. This characteristic is particularly appropriate for a wireless sensor node which requires the function of both encryption and decryption. Further, in order to consider the suitability of a cipher for application to a wireless sensor node, which is an energy constrained device, it is most critical to consider the cost of encryption in terms of energy consumption. Hence, we choose two involutional block ciphers, KHAZAD and BSPN, and analyze their energy efficiency for FPGA implementation.     

Stateful-NOR based reconfigurable architecture for logic implementation

Most commercial Field Programmable Gate Arrays (FPGAs) have limitations in terms of density, speed, configuration overhead and power consumption mostly due to the use of SRAM cells in Look-Up Tables (LUTs), configuration memory and programmable interconnects. Also, hardwired Application Specific Integrated Circuit (ASIC) blocks designed for high performance arithmetic circuits in FPGA reduce the area available for reconfiguration. In this paper, we propose a novel generalized hybrid CMOS-memristor based architecture using stateful-NOR gates as basic building blocks for implementation of logic functions. These logic functions are implemented on memristor nanocrossbar layers, while the CMOS layer is used for selection and connection of memristors. The proposed pipelined architecture combines the features of ASIC, FPGA and microprocessor based designs. It has high density due to the use of nanocrossbar layer and high throughput especially for arithmetic circuits. The proposed architecture for three input one output logic block is compared with conventional LUT based Configurable Logic Block (CLB) having the same number of inputs and outputs; which shows 1.82×area saving, 1.57×speedup and 3.63×less power consumption. The automation algorithm to implement any logic function using proposed architecture is also presented.     

IDEA算法中关键模块的实现

采用FPGA技术，实现了IDEA算法，重点介绍了其关键功能模块的设计实现。根据IDEA密钥扩展方式和加解密流程，对IDEA的功能模块进行了划分和设计。其中，对复杂度较高而又不要求实时高速的模乘逆运算，进行了耗时分析；而对直接影响加解密速度的模乘运算，提出了一种新的模乘结构。