此篇博客，仅此纪念国庆七天长假的折磨。。。
///DES
#include<stdio.h>
#include<string.h>
#include<string>
using namespace std;
int IP_Table[64] = { //IP置换矩阵
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 };
int E_Table[48] = { //扩展矩阵
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 };
int P_Table[32] = { // P 盒
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 };
int IPR_Table[64] = { //逆IP置换矩阵
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 };
int PC1_Table[56] = { //密钥第一次置换矩阵
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 };
int PC2_Table[48] = { // 密钥第二次置换矩阵
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 };
int S_Box[8][4][16] = { //8个S盒 三维数组
// S1
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,
// S2
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,
// S3
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,
// S4
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,
// S5
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,
// S6
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,
// S7
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,
// S8
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};
static void CharToBit(const char input[], int output[], int bits)//把CHAR转换为INT
{
int i, j;
for (j = 0; j<8; j++)
{
for (i = 0; i<8; i++)
{
output[7 * (j + 1) - i + j] = (input[j] >> i) & 1;
}
}
};
static void BitToChar(const int intput[], char output[], int bits)//把INT转换为CHAR
{
int i, j;
for (j = 0; j<8; j++)
{
for (i = 0; i<8; i++)
{
output[j] = output[j] * 2 + intput[i + 8 * j];
}
}
};
static void Xor(int *INA, int *INB, int len)//异或操作
{
int i;
for (i = 0; i<len; i++)
{
*(INA + i) = *(INA + i) ^ *(INB + i);
}
};
static void IP(const int input[64], int output[64], int table[64])//初始IP置换
{
int i;
for (i = 0; i<64; i++)
{
output[i] = input[table[i] - 1];//减1操作不可少！！
}
};
static void E(const int input[32], int output[48], int table[48])//E扩展
{
int i;
for (i = 0; i<48; i++)
{
output[i] = input[table[i] - 1];
}
};
static void P(const int input[32], int output[32], int table[32])//P置换
{
int i;
for (i = 0; i<32; i++)
{
output[i] = input[table[i] - 1];
}
};
static void IP_In(const int input[64], int output[64], int table[64])//逆IP
{
int i;
for (i = 0; i<64; i++)
{
output[i] = input[table[i] - 1];
}
};
static void PC_1(const int input[64], int output[56], int table[56])//PC_1
{
int i;
for (i = 0; i<56; i++)
{
output[i] = input[table[i] - 1];
}
};
static void PC_2(const int input[56], int output[48], int table[48])//PC_2
{
int i;
for (i = 0; i<48; i++)
{
output[i] = input[table[i] - 1];
}
};
static void S(const int input[48], int output[32], int table[8][4][16])//S盒压缩
{
int i = 0;
int j = 0;
int INT[8];
for (; i<48; i = i + 6)
{
INT[j] = table[j][(input[i] << 1) + (input[i + 5])][(input[i + 1] << 3) + (input[i + 2] << 2) + (input[i + 3] << 1) + (input[i + 4])];
j++;
}
for (j = 0; j<8; j++)
{
for (i = 0; i<4; i++)
{
output[3 * (j + 1) - i + j] = (INT[j] >> i) & 1;
}
}
};
static void F_func(int input[32], int output[32], int subkey[48])//完成DES算法轮变换
{
int len = 48;
int temp[48] = { 0 };
int temp_1[32] = { 0 };
E(input, temp, E_Table);//E扩展
Xor(temp, subkey, len);//异或操作
S(temp, temp_1, S_Box);//s盒置换
P(temp_1, output, P_Table);//p盒置换
};
static void RotateL(const int input[28], int output[28], int leftCount)//秘钥循环左移
{
int i;
int len = 28;
for (i = 0; i<len; i++)
{
output[i] = input[(i + leftCount) % len];
}
};
static void subKey_fun(const int input[64], int Subkey[16][48])//子密钥生成
{
int loop = 1, loop_2 = 2;
int i, j;
int c[28], d[28];
int pc_1[56] = { 0 };//存储密钥的初级置换
int pc_2[16][56] = { 0 };
int rotatel_c[16][28] = { 0 };
int rotatel_d[16][28] = { 0 };
PC_1(input, pc_1, PC1_Table);
for (i = 0; i<28; i++) //密钥分组
{
c[i] = pc_1[i];
d[i] = pc_1[i + 28];
}
int leftCount = 0;
for (i = 1; i<17; i++) //16密钥循环位移
{
if (i == 1 || i == 2 || i == 9 || i == 16)
{
leftCount += loop;
RotateL(c, rotatel_c[i - 1], leftCount);
RotateL(d, rotatel_d[i - 1], leftCount);
}
else
{
leftCount += loop_2;
RotateL(c, rotatel_c[i - 1], leftCount);
RotateL(d, rotatel_d[i - 1], leftCount);
}
}
for (i = 0; i<16; i++) //密钥合并
{
for (j = 0; j<28; j++)
{
pc_2[i][j] = rotatel_c[i][j];
pc_2[i][j + 28] = rotatel_d[i][j];
}
}
for (i = 0; i<16; i++)//密钥第二次置换
{
PC_2(pc_2[i], Subkey[i], PC2_Table);
}
};
static void DES_Efun(char input[8], char key_in[8], char output[64])
{
int Ip[64] = { 0 };//存储初始置换后的矩阵
int output_1[64] = { 0 },output_3[64] = { 0 };
int subkeys[16][48];//置换后的密钥
int chartobit[64] = { 0 };//存储明文的二进制
int key[64]={0};//存储密钥的二进制
int l[17][32], r[17][32];
CharToBit(input, chartobit, 8);//转换为64个二进制数的操作正确！
IP(chartobit, Ip, IP_Table);//IP初始置换！
CharToBit(key_in, key, 8);//正确！密钥转换二进制
subKey_fun(key, subkeys);//正确！密钥置换
for (int i = 0; i<32; i++) //明文分组
{
l[0][i] = Ip[i];
r[0][i] = Ip[32 + i];
}
for (int j = 1; j<16; j++)//前15轮的操作
{
for (int k = 0; k<32; k++)
{
l[j][k] = r[j - 1][k];
}
F_func(r[j - 1], r[j], subkeys[j - 1]);//DES混淆转换操作
Xor(r[j], l[j - 1], 32);//异或运算
}
int t = 0;
for (t = 0; t<32; t++)//最后一轮的操作
{
r[16][t] = r[15][t];
}
F_func(r[15], l[16], subkeys[15]);//DES置换操作
Xor(l[16], l[15], 32);//异或运算
for (t = 0; t<32; t++)//合并数组
{
output_1[t] = l[16][t];
output_1[32 + t] = r[16][t];
}
IP_In(output_1, output_3, IPR_Table);//逆运算IP
BitToChar(output_3, output, 8);//将字节转换为字符
};
static void DES_Dfun(int input[64], char key_in[8], char output[8])//解密过程
{
int Ip[64] = { 0 };//存储初始置换后的矩阵
int output_1[64] = {0};
int output_2[64] = {0};
int subkeys[16][48];
int chartobit[64] = { 0 };
int key[64];
int l[17][32], r[17][32];
IP(input, Ip, IP_Table);//正确，IP初始置换！
CharToBit(key_in, key, 8);//正确！
subKey_fun(key, subkeys);//正确！
for (int i = 0; i<32; i++)
{
l[0][i] = Ip[i];
r[0][i] = Ip[32 + i];
}
for (int j = 1; j<16; j++)//前15轮的操作
{
for (int k = 0; k<32; k++)
{
l[j][k] = r[j - 1][k];
}
F_func(r[j - 1], r[j], subkeys[16 - j]);
Xor(r[j], l[j - 1], 32);//异或运算
}
int t = 0;
for (t = 0; t<32; t++)//最后一轮的操作
{
r[16][t] = r[15][t];
}
F_func(r[15], l[16], subkeys[0]);
Xor(l[16], l[15], 32);//异或运算
for (t = 0; t<32; t++)
{
output_1[t] = l[16][t];
output_1[32 + t] = r[16][t];
}
IP_In(output_1, output_2, IPR_Table);
BitToChar(output_2, output, 8);
};
int main()
{
char output[8] = { 0 };//存储密文
int output_4[64]={0};
char MIN[9] = { 0 };//存入明文
char MI[9] = { 0 };//存入密钥
printf("请输入明文(8字节)\n");
gets(MIN);
printf("请输入秘钥(8字节)\n");
gets(MI);
DES_Efun(MIN, MI, output);//加密操作
printf("密文如下:\n");
for (int i = 0; i<8; i++)
{
printf("%c", output[i]);
}
printf("\n");
printf("解密功能\n");
CharToBit(output,output_4,8);//字符转换
DES_Dfun(output_4, MI, MIN);//解密操作
printf("明文如下:\n");
for (int i = 0; i<8; i++)
{
printf("%c", MIN[i]);
}
printf("\n\n");
return 0;
}