DES子秘钥生成算法的代码
时间: 2023-05-27 22:03:07 浏览: 85
由于DES算法的密钥生成算法非常复杂,包含多个步骤,因此这里提供的代码只是其中的一部分示例。
```
/**
* DES密钥生成算法
* @param key 原始密钥(64位二进制字符串)
* @return 16个子密钥(每个密钥48位二进制字符串)
*/
public static String[] generateSubkeys(String key) {
// 将原始密钥转换成56位二进制字符串
String binaryKey = hexToBinary(key);
String binaryKey56 = permute(binaryKey, PC1_TABLE);
// 将56位二进制密钥分成左右两部分
String left = binaryKey56.substring(0, 28);
String right = binaryKey56.substring(28);
String[] subkeys = new String[16];
for (int i = 0; i < 16; i++) {
// 左右移位
left = leftShift(left, SHIFTS[i]);
right = leftShift(right, SHIFTS[i]);
// 合并左右部分并进行二进制置换
String combined = left + right;
subkeys[i] = permute(combined, PC2_TABLE);
}
return subkeys;
}
// 以下是常量表
// 初始密钥置换表,将64位密钥压缩成56位
private static final int[] PC1_TABLE = new int[]{
57, 49, 41, 33, 25, 17, 9, 1, 58, 50,
42, 34, 26, 18, 10, 2, 59, 51, 43, 35,
27, 19, 11, 3, 60, 52, 44, 36, 63, 55,
47, 39, 31, 23, 15, 7, 62, 54, 46, 38,
30, 22, 14, 6, 61, 53, 45, 37, 29, 21,
13, 5, 28, 20, 12, 4
};
// 压缩置换表,将56位密钥压缩成48位子密钥
private static final int[] PC2_TABLE = new int[]{
14, 17, 11, 24, 1, 5, 3, 28, 15, 6,
21, 10, 23, 19, 12, 4, 26, 8, 16, 7,
27, 20, 13, 2, 41, 52, 31, 37, 47, 55,
30, 40, 51, 45, 33, 48, 44, 49, 39, 56,
34, 53, 46, 42, 50, 36, 29, 32
};
// 循环移位表,用于左移和右移
private static final int[] SHIFTS = new int[]{
1, 1, 2, 2, 2, 2, 2, 2, 1, 2, 2, 2, 2, 2, 2, 1
};
```