用C和Java语言，实现一个的DES算法逻辑

用C和Java语言，实现一个的DES算法逻辑。
1.说明算法思想
2.程序（详细注释）
3.实验结果

public class InDES {
// 声明常量字节数组
private static final int[] IP = {
58, 50, 42, 34, 26, 18, 10, 2, 60, 52, 44, 36, 28, 20, 12, 4, 62, 54,
46, 38, 30, 22, 14, 6, 64, 56, 48, 40, 32, 24, 16, 8, 57, 49, 41, 33,
25, 17, 9, 1, 59, 51, 43, 35, 27, 19, 11, 3, 61, 53, 45, 37, 29, 21,
13, 5, 63, 55, 47, 39, 31, 23, 15, 7
}; // 64
private static final int[] IP_1 = {
40, 8, 48, 16, 56, 24, 64, 32, 39, 7, 47, 15, 55, 23, 63, 31, 38, 6,
46, 14, 54, 22, 62, 30, 37, 5, 45, 13, 53, 21, 61, 29, 36, 4, 44, 12,
52, 20, 60, 28, 35, 3, 43, 11, 51, 19, 59, 27, 34, 2, 42, 10, 50, 18,
58, 26, 33, 1, 41, 9, 49, 17, 57, 25
}; // 64
private static final int[] PC_1 = {
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
}; // 56
private static final int[] PC_2 = {
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
}; // 48
private static final int[] E = {
32, 1, 2, 3, 4, 5, 4, 5, 6, 7, 8, 9, 8, 9, 10, 11, 12, 13, 12, 13,
14, 15, 16, 17, 16, 17, 18, 19, 20, 21, 20, 21, 22, 23, 24, 25, 24,
25, 26, 27, 28, 29, 28, 29, 30, 31, 32, 1
}; // 48
private static final int[] P = {
16, 7, 20, 21, 29, 12, 28, 17, 1, 15, 23, 26, 5, 18, 31, 10, 2, 8,
24, 14, 32, 27, 3, 9, 19, 13, 30, 6, 22, 11, 4, 25
}; // 32
private static final int[][][] S_Box = {
{
{ 14, 4, 13, 1, 2, 15, 11, 8, 3, 10, 6, 12, 5, 9, 0, 7 },
{ 0, 15, 7, 4, 14, 2, 13, 1, 10, 6, 12, 11, 9, 5, 3, 8 },
{ 4, 1, 14, 8, 13, 6, 2, 11, 15, 12, 9, 7, 3, 10, 5, 0 },
{ 15, 12, 8, 2, 4, 9, 1, 7, 5, 11, 3, 14, 10, 0, 6, 13 }
},
{ // S_Box[1]
{ 15, 1, 8, 14, 6, 11, 3, 4, 9, 7, 2, 13, 12, 0, 5, 10 },
{ 3, 13, 4, 7, 15, 2, 8, 14, 12, 0, 1, 10, 6, 9, 11, 5 },
{ 0, 14, 7, 11, 10, 4, 13, 1, 5, 8, 12, 6, 9, 3, 2, 15 },
{ 13, 8, 10, 1, 3, 15, 4, 2, 11, 6, 7, 12, 0, 5, 14, 9 }
},
{ // S_Box[2]
{ 10, 0, 9, 14, 6, 3, 15, 5, 1, 13, 12, 7, 11, 4, 2, 8 },
{ 13, 7, 0, 9, 3, 4, 6, 10, 2, 8, 5, 14, 12, 11, 15, 1 },
{ 13, 6, 4, 9, 8, 15, 3, 0, 11, 1, 2, 12, 5, 10, 14, 7 },
{ 1, 10, 13, 0, 6, 9, 8, 7, 4, 15, 14, 3, 11, 5, 2, 12 }
},
{ // S_Box[3]
{ 7, 13, 14, 3, 0, 6, 9, 10, 1, 2, 8, 5, 11, 12, 4, 15 },
{ 13, 8, 11, 5, 6, 15, 0, 3, 4, 7, 2, 12, 1, 10, 14, 9 },
{ 10, 6, 9, 0, 12, 11, 7, 13, 15, 1, 3, 14, 5, 2, 8, 4 },
{ 3, 15, 0, 6, 10, 1, 13, 8, 9, 4, 5, 11, 12, 7, 2, 14 }
},
{ // S_Box[4]
{ 2, 12, 4, 1, 7, 10, 11, 6, 8, 5, 3, 15, 13, 0, 14, 9 },
{ 14, 11, 2, 12, 4, 7, 13, 1, 5, 0, 15, 10, 3, 9, 8, 6 },
{ 4, 2, 1, 11, 10, 13, 7, 8, 15, 9, 12, 5, 6, 3, 0, 14 },
{ 11, 8, 12, 7, 1, 14, 2, 13, 6, 15, 0, 9, 10, 4, 5, 3 }
},
{ // S_Box[5]
{ 12, 1, 10, 15, 9, 2, 6, 8, 0, 13, 3, 4, 14, 7, 5, 11 },
{ 10, 15, 4, 2, 7, 12, 9, 5, 6, 1, 13, 14, 0, 11, 3, 8 },
{ 9, 14, 15, 5, 2, 8, 12, 3, 7, 0, 4, 10, 1, 13, 11, 6 },
{ 4, 3, 2, 12, 9, 5, 15, 10, 11, 14, 1, 7, 6, 0, 8, 13 }
},
{ // S_Box[6]
{ 4, 11, 2, 14, 15, 0, 8, 13, 3, 12, 9, 7, 5, 10, 6, 1 },
{ 13, 0, 11, 7, 4, 9, 1, 10, 14, 3, 5, 12, 2, 15, 8, 6 },
{ 1, 4, 11, 13, 12, 3, 7, 14, 10, 15, 6, 8, 0, 5, 9, 2 },
{ 6, 11, 13, 8, 1, 4, 10, 7, 9, 5, 0, 15, 14, 2, 3, 12 }
},
{ // S_Box[7]
{ 13, 2, 8, 4, 6, 15, 11, 1, 10, 9, 3, 14, 5, 0, 12, 7 },
{ 1, 15, 13, 8, 10, 3, 7, 4, 12, 5, 6, 11, 0, 14, 9, 2 },
{ 7, 11, 4, 1, 9, 12, 14, 2, 0, 6, 10, 13, 15, 3, 5, 8 },
{ 2, 1, 14, 7, 4, 10, 8, 13, 15, 12, 9, 0, 3, 5, 6, 11 }
} // S_Box[8]
};
private static final int[] LeftMove = {
1, 1, 2, 2, 2, 2, 2, 2, 1, 2, 2, 2, 2, 2, 2, 1
}; // 左移位置列表

private byte[] UnitDes(byte[] des_key, byte[] des_data, int flag) {
// 检测输入参数格式是否正确，错误直接返回空值（null）
if ((des_key.length != 8) || (des_data.length != 8) ||
((flag != 1) && (flag != 0))) {
throw new RuntimeException("Data Format Error !");
}
int flags = flag;
// 二进制加密密钥
int[] keydata = new int[64];
// 二进制加密数据
int[] encryptdata = new int[64];
// 加密操作完成后的字节数组
byte[] EncryptCode = new byte[8];
// 密钥初试化成二维数组
int[][] KeyArray = new int[16][48];
// 将密钥字节数组转换成二进制字节数组
keydata = ReadDataToBirnaryIntArray(des_key);
// 将加密数据字节数组转换成二进制字节数组
encryptdata = ReadDataToBirnaryIntArray(des_data);
// 初试化密钥为二维密钥数组
KeyInitialize(keydata, KeyArray);
// 执行加密解密操作
EncryptCode = Encrypt(encryptdata, flags, KeyArray);
return EncryptCode;
}

// 初试化密钥数组
private void KeyInitialize(int[] key, int[][] keyarray) {
int i;
int j;
int[] K0 = new int[56];
// 特别注意：xxx[IP[i]-1]等类似变换
for (i = 0; i < 56; i++) {
K0[i] = key[PC_1[i] - 1]; // 密钥进行PC-1变换
}
for (i = 0; i < 16; i++) {
LeftBitMove(K0, LeftMove[i]);
// 特别注意：xxx[IP[i]-1]等类似变换
for (j = 0; j < 48; j++) {
keyarray[i][j] = K0[PC_2[j] - 1]; // 生成子密钥keyarray[i][j]
}
}
}

// 执行加密解密操作
private byte[] Encrypt(int[] timeData, int flag, int[][] keyarray) {
int i;
byte[] encrypt = new byte[8];
int flags = flag;
int[] M = new int[64];
int[] MIP_1 = new int[64];
// 特别注意：xxx[IP[i]-1]等类似变换
for (i = 0; i < 64; i++) {
M[i] = timeData[IP[i] - 1]; // 明文IP变换
}
if (flags == 1) { // 加密
for (i = 0; i < 16; i++) {
LoopF(M, i, flags, keyarray);
}
} else if (flags == 0) { // 解密
for (i = 15; i > -1; i--) {
LoopF(M, i, flags, keyarray);
}
}
for (i = 0; i < 64; i++) {
MIP_1[i] = M[IP_1[i] - 1]; // 进行IP-1运算
}
GetEncryptResultOfByteArray(MIP_1, encrypt);
// 返回加密数据
return encrypt;
}

private int[] ReadDataToBirnaryIntArray(byte[] intdata) {
int i;
int j;
// 将数据转换为二进制数，存储到数组
int[] IntDa = new int[8];
for (i = 0; i < 8; i++) {
IntDa[i] = intdata[i];
if (IntDa[i] < 0) {
IntDa[i] += 256;
IntDa[i] %= 256;
}
}
int[] IntVa = new int[64];
for (i = 0; i < 8; i++) {
for (j = 0; j < 8; j++) {
IntVa[((i * 8) + 7) - j] = IntDa[i] % 2;
IntDa[i] = IntDa[i] / 2;
}
}
return IntVa;
}

private void LeftBitMove(int[] k, int offset) {
int i;
// 循环移位操作函数
int[] c0 = new int[28];
int[] d0 = new int[28];
int[] c1 = new int[28];
int[] d1 = new int[28];
for (i = 0; i < 28; i++) {
c0[i] = k[i];
d0[i] = k[i + 28];
}
if (offset == 1) {
for (i = 0; i < 27; i++) { // 循环左移一位
c1[i] = c0[i + 1];
d1[i] = d0[i + 1];
}
c1[27] = c0[0];
d1[27] = d0[0];
} else if (offset == 2) {
for (i = 0; i < 26; i++) { // 循环左移两位
c1[i] = c0[i + 2];
d1[i] = d0[i + 2];
}
c1[26] = c0[0];
d1[26] = d0[0];
c1[27] = c0[1];
d1[27] = d0[1];
}
for (i = 0; i < 28; i++) {
k[i] = c1[i];
k[i + 28] = d1[i];
}
}