Efficient byte permutation realizations for compact AES implementations
Efficient byte permutation realizations for compact AES implementations
复制标题
紧凑 AES 实现的高效字节排列实现
DOI：
10.5281/zenodo.39319
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发表时间：
2005
期刊：
影响因子：
--
通讯作者：
J. Takala
中科院分区：
文献类型：
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作者：
Tuomas Järvinen;P. Salmela;Panu Hämäläinen;J. Takala
高级加密标准（AES）算法结合了字节置换操作，该操作对128位数据块内的字节进行重新排序。这种置换可以通过将输入数据字节阅读到一个4×4矩阵中来描述，该矩阵被称为列方式的状态，并将行向左移动一个、两个或三个字节。在解密中，移位被反转，即，行向右移动。虽然如果一次用128位数据块完成计算，则这种移位操作是直接的，但是在使用小于128位数据块的面积有效的折叠实现中，它们变得更加复杂。在这种情况下，需要以寄存器或存储器的形式存储数据。本文给出了AES算法中字节置换的有效实现，其中同时计算的数据量可以是1、2、4或8字节。所有的实现都使用了最少数量的存储元件，这意味着面积效率。
Advanced Encryption Standard (AES) algorithm incorporates a byte permutation operation which reorders the bytes within a 128-bit data block. This permutation can be described by reading the input data bytes into a 4×4 matrix called state in column wise and shifting the rows by one, two, or three bytes to the left. In decryption, the shifting is reversed, i.e., the rows are shifted to the right. While such shifting operations are straightforward if the computation is done with 128-bit data blocks at a time, they become more complex in area-efficient folded implementations where smaller than 128-bit data blocks are used. In such cases, a storage of data is required, either in the form of registers or memories. In this paper, efficient realizations of the byte permutations in AES algorithm, where the size of simultaneously computed data can be 1, 2, 4, or 8 bytes, are presented. All the realizations use the minimum number of storage elements implying area-efficiency.