使用 Cryptol-list 问题实现 GIFT-COFB 算法

Question

我已经是 Haskell 的 Cryptol 方言新手，而且我很生气，因为我不能使用循环... 我想像这样实现数组... Initialization Matrix but I have the only idea to get every 4th element starting by [0] index and load this new list to S0. Similarly starting by 1 列表的索引并每第 4 个元素加载到新的 S1 数组。

Answer 1

Cryptol 的类型系统旨在让您在加密算法中发现的这些位分割几乎可以轻松表达。事实上，一旦你习惯了这种风格，没有循环是一个优点，而不是一个缺点。

可能有多种方法来编写您的“初始化”代码。但我会这样做：

load : {a} [128][a] -> [4][32][a]
load(elts) = reverse (transpose cols)
  where cols : [32][4][a]
        cols = split elts

请注意，此处的类型比您需要的更通用，但它可以更轻松地进行测试。这是我在密码提示符下得到的：

Main> :set base=10
Main> load [127, 126 .. 0]
Showing a specific instance of polymorphic result:
  * Using '7' for type argument 'a' of 'Main::load'
[[124, 120, 116, 112, 108, 104, 100, 96, 92, 88, 84, 80, 76, 72,
  68, 64, 60, 56, 52, 48, 44, 40, 36, 32, 28, 24, 20, 16, 12, 8, 4,
  0],
 [125, 121, 117, 113, 109, 105, 101, 97, 93, 89, 85, 81, 77, 73, 69,
  65, 61, 57, 53, 49, 45, 41, 37, 33, 29, 25, 21, 17, 13, 9, 5, 1],
 [126, 122, 118, 114, 110, 106, 102, 98, 94, 90, 86, 82, 78, 74, 70,
  66, 62, 58, 54, 50, 46, 42, 38, 34, 30, 26, 22, 18, 14, 10, 6, 2],
 [127, 123, 119, 115, 111, 107, 103, 99, 95, 91, 87, 83, 79, 75, 71,
  67, 63, 59, 55, 51, 47, 43, 39, 35, 31, 27, 23, 19, 15, 11, 7, 3]]

这有点难读，所以这里是格式化的：

[[124, 120, 116, 112, 108, 104, 100, 96, 92, 88, 84, 80, 76, 72, 68, 64, 60, 56, 52, 48, 44, 40, 36, 32, 28, 24, 20, 16, 12, 8, 4,  0],
 [125, 121, 117, 113, 109, 105, 101, 97, 93, 89, 85, 81, 77, 73, 69, 65, 61, 57, 53, 49, 45, 41, 37, 33, 29, 25, 21, 17, 13, 9, 5, 1],
 [126, 122, 118, 114, 110, 106, 102, 98, 94, 90, 86, 82, 78, 74, 70, 66, 62, 58, 54, 50, 46, 42, 38, 34, 30, 26, 22, 18, 14, 10, 6, 2],
 [127, 123, 119, 115, 111, 107, 103, 99, 95, 91, 87, 83, 79, 75, 71,  67, 63, 59, 55, 51, 47, 43, 39, 35, 31, 27, 23, 19, 15, 11, 7, 3]]

这正是您想要的结构。现在我们可以专攻：

loadBits : [128] -> [4][32]
loadBits(vector) = reverse (transpose cols)
  where cols : [32][4]
        cols = split vector

请注意，代码与之前完全相同，我们只是将其具体化为您想要的类型。

希望这能让你入门！

使用 Cryptol-list 问题实现 GIFT-COFB 算法

Implementing GIFT-COFB algorithm using Cryptol- list problem

cryptography

functional-programming

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cryptol