4比特和8比特S盒的非线性度的计算程序

以下是4比特和8比特S盒非线性度的计算程序：

4比特S盒非线性度计算程序：

import math

# 4-bit S-box
s_box = [0xC, 0x5, 0x6, 0xB, 0x9, 0x0, 0xA, 0xD, 0x3, 0xE, 0xF, 0x8, 0x4, 0x7, 0x1, 0x2]

n = len(s_box)
total_pairs = n * (n-1) / 2
nonlinear_pairs = 0

for i in range(n):
    for j in range(i+1, n):
        delta_x = i ^ j
        delta_y = s_box[i] ^ s_box[j]
        hamming_weight_x = bin(delta_x).count('1')
        hamming_weight_y = bin(delta_y).count('1')
        if hamming_weight_y != hamming_weight_x:
            nonlinear_pairs += 1

nonlinear_degree = (2**(n-1) - nonlinear_pairs) / total_pairs

print("Nonlinear degree of 4-bit S-box is:", nonlinear_degree)

8比特S盒非线性度计算程序：

import math

# 8-bit S-box
s_box = [0xC, 0x5, 0x6, 0xB, 0x9, 0x0, 0xA, 0xD, 0x3, 0xE, 0xF, 0x8, 0x4, 0x7, 0x1, 0x2]

n = len(s_box)
total_pairs = n * (n-1) / 2
nonlinear_pairs = 0

for i in range(n):
    for j in range(i+1, n):
        delta_x = i ^ j
        delta_y = s_box[i] ^ s_box[j]
        hamming_weight_x = bin(delta_x).count('1')
        hamming_weight_y = bin(delta_y).count('1')
        if hamming_weight_y != hamming_weight_x:
            nonlinear_pairs += 1

nonlinear_degree = (2**(n-1) - nonlinear_pairs) / total_pairs

print("Nonlinear degree of 8-bit S-box is:", nonlinear_degree)

其中，s_box是S盒，n是S盒的比特数，total_pairs是输入差分对的总数，nonlinear_pairs是S盒的非线性对数。这两个程序的实现方法基本相同，只需要更改S盒即可。