头文件DES.h
#ifndef _DES_ENCRYPT_DECRYPT
#define _DES_ENCRYPT_DECRYPT
#define BYTE unsigned char
#define LPBYTE BYTE*
#define LPCBYTE const BYTE*
#define BOOL int
class DES
{
public:
BOOL CDesEnter(LPCBYTE in, LPBYTE out, int datalen, const BYTE key[8], BOOL type);
BOOL CDesMac(LPCBYTE mac_data, LPBYTE mac_code, int datalen, const BYTE key[8]);
private:
void XOR(const BYTE in1[8], const BYTE in2[8], BYTE out[8]);
LPBYTE Bin2ASCII(const BYTE byte[64], BYTE bit[8]);
LPBYTE ASCII2Bin(const BYTE bit[8], BYTE byte[64]);
void GenSubKey(const BYTE oldkey[8], BYTE newkey[16][8]);
void endes(const BYTE m_bit[8], const BYTE k_bit[8], BYTE e_bit[8]);
void undes(const BYTE m_bit[8], const BYTE k_bit[8], BYTE e_bit[8]);
void SReplace(BYTE s_bit[8]);
};
BOOL DES::CDesEnter(LPCBYTE in, LPBYTE out, int datalen, const BYTE key[8], BOOL type)
{
//判断输入参数是否正确，失败的情况为：
//!in： in指针（输入缓冲）无效
//!out： out指针（输出缓冲）无效
//datalen<1： 数据长度不正确
//!key： 加/解密密码无效
//type && ((datalen % 8) !=0：选择解密方式但是输入密文不为8的倍数
if((!in) || (!out) || (datalen<1) || (!key) || (type && ((datalen % 8) !=0)))
return false;
if(type==0) //选择的模式是加密
{
// 用于存储待加密字串最后的若干字节
// DES算法是以8个字节为单位进行加密，如果待加密字串以8为单位分段加密时，最后一段不足 0>.'w\,87B
//8字节，则在后面补0，使其最后一段的长度为8字节
// te8bit是作为存储待加密字串最后一段（不足8字节）的变量
BYTE te8bit[8]={0,0,0,0,0,0,0,0};
// 这是待加密字串的调整长度
// 如果原始长度是8的整数倍，则调整长度的值和原来的长度一样
// 如果原始长度不是8的整数倍，则调整长度的值是能被8整除且不大于原来长度的最大整数。
//也就是不需要补齐的块的总长度。
int te_fixlen = datalen - (datalen % 8);
// 将待加密密文以8为单位分段，把最后长度不足8的一段存储到te8bit中。
for(int i = 0; i < (datalen % 8); i++)
te8bit[i] = in[te_fixlen + i];
// 将待加密字串分以8字节为单位分段加密
for(i = 0; i < te_fixlen; i += 8)
endes(in + i, key, out + i);
// 如果待加密字串不是8的整数倍，则将最后一段补齐（补0）后加密
if(datalen % 8 != 0)
endes(te8bit, key, out + datalen / 8 * 8);
}
else //选择的模式是解密
{
// 将密文以8字节为单位分段解密
for(int i = 0; i < datalen; i += 8)
undes(in + i, key, out + i);
}
return true;
}
BOOL DES::CDesMac(LPCBYTE mac_data, LPBYTE mac_code, int datalen, const BYTE key[8])
{
//判断输入参数是否正确，失败的情况为：
//!mac_data： mac_data指针（输入缓冲）无效
//!mac_code： mac_code指针（输出缓冲）无效
//datalen<16： 数据长度不正确
//datalen % 8 != 0： 数据长度不为8的整数倍
//!key：密码不符合要求
if((!mac_data) || (!mac_code) || (datalen < 16) || (datalen % 8 != 0) || (!key))
return false;
endes(mac_data, key, mac_code);
for(int i = 8; i < datalen; i += 8)
{
XOR(mac_code, mac_data + i, mac_code);
endes(mac_code, key, mac_code);
}
return true;
}
void DES::XOR(const BYTE in1[8], const BYTE in2[8], BYTE out[8])
{
for(int i = 0; i < 8; i++)
out[i] = in1[i] ^ in2[i];
}
LPBYTE DES::Bin2ASCII(const BYTE byte[64], BYTE bit[8])
{
for(int i = 0; i < 8; i++)
{
bit[i] = byte[i * 8] * 128 + byte[i * 8 + 1] * 64 +
byte[i * 8 + 2] * 32 + byte[i * 8 + 3] * 16 +
byte[i * 8 + 4] * 8 + byte[i * 8 + 5] * 4 +
byte[i * 8 + 6] * 2 + byte[i * 8 + 7];
}
return bit;
}
LPBYTE DES::ASCII2Bin(const BYTE bit[8], BYTE byte[64])
{
for(int i=0; i < 8; i++)
for(int j = 0; j < 8; j++)
byte[i * 8 + j] = ( bit[i] >> (7 - j) ) & 0x01;
return byte;
}
void DES::GenSubKey(const BYTE oldkey[8], BYTE newkey[16][8])
{
int i, k, rol = 0;
//缩小换位表1
int pc_1[56] = {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};
//缩小换位表2
int pc_2[48] = {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};
//16次循环左移对应的左移位数
int ccmovebit[16] = {1,1,2,2,2,2,2,2,1,2,2,2,2,2,2,1};
BYTE oldkey_byte[64];
BYTE oldkey_byte1[64];
BYTE oldkey_byte2[64];
BYTE oldkey_c[56];
BYTE oldkey_d[56];
BYTE newkey_byte[16][64];
ASCII2Bin(oldkey, oldkey_byte);
//位变换 .
for(i = 0; i < 56; i++)
oldkey_byte1[i] = oldkey_byte[pc_1[i] - 1];
//分为左右两部分，复制一遍以便于循环左移
for(i = 0; i < 28; i++)
oldkey_c[i] = oldkey_byte1[i], oldkey_c[i + 28] = oldkey_byte1[i],
oldkey_d[i] = oldkey_byte1[i + 28], oldkey_d[i + 28] = oldkey_byte1[i + 28];
//分别生成16个子密钥
for(i = 0; i < 16; i++)
{
//循环左移 3
rol += ccmovebit[i];
//合并左移后的结果
for(k = 0; k < 28; k++)
oldkey_byte2[k] = oldkey_c[k + rol], oldkey_byte2[k + 28] = oldkey_d[k + rol];
//位变换
for(k = 0; k < 48; k++)
newkey_byte[i][k] = oldkey_byte2[pc_2[k] - 1];
}
//生成最终结果
for(i = 0; i < 16; i++)
Bin2ASCII(newkey_byte[i], newkey[i]);
}
void DES::endes(const BYTE m_bit[8], const BYTE k_bit[8], BYTE e_bit[8])
{
//换位表IP
int ip[64] = {
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
};
//换位表IP_1
int ip_1[64] ={
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
};
//放大换位表
int e[48] = {
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
};
BYTE m_bit1[8] = {0};
BYTE m_byte[64] = {0};
BYTE m_byte1[64] = {0};
BYTE key_n[16][8] = {0};
BYTE l_bit[17][8] = {0};
BYTE r_bit[17][8] = {0};
BYTE e_byte[64] = {0};
BYTE e_byte1[64] = {0};
BYTE r_byte[64] = {0};
BYTE r_byte1[64] = {0};
int i, j;
//根据密钥生成16个子密钥
GenSubKey(k_bit, key_n);
//将待加密字串变换成01串
ASCII2Bin(m_bit, m_byte);
//按照ip表对待加密字串进行位变换
for(i = 0; i < 64; i++)
m_byte1[i] = m_byte[ip[i] - 1];
//位变换后的待加密字串
Bin2ASCII(m_byte1, m_bit1);
//将位变换后的待加密字串分成两组，分别为前4字节L和后4字节R，作为迭代的基础（第0次迭代
for(i = 0; i < 4; i++)
l_bit[0][i] = m_bit1[i], r_bit[0][i] = m_bit1[i + 4];
//16次迭代运算
for(i = 1; i <= 16; i++)
{
//R的上一次的迭代结果作为L的当前次迭代结果
for(j = 0; j < 4; j++)
l_bit[i][j] = r_bit[i-1][j];
ASCII2Bin(r_bit[i-1], r_byte);
//将R的上一次迭代结果按E表进行位扩展得到48位中间结果
for(j = 0; j < 48; j++)
r_byte1[j] = r_byte[e[j] - 1];
Bin2ASCII(r_byte1, r_bit[i-1]);
//与第I-1个子密钥进行异或运算
for(j = 0; j < 6; j++)
r_bit[i-1][j] = r_bit[i-1][j] ^ key_n[i-1][j];
//进行S选择，得到32位中间结果
SReplace(r_bit[i - 1]);
//结果与L的上次迭代结果异或得到R的此次迭代结果
for(j = 0; j < 4; j++)
{
r_bit[i][j] = l_bit[i-1][j] ^ r_bit[i-1][j];
}
}
//组合最终迭代结果
for(i = 0; i < 4; i++)
e_bit[i] = r_bit[16][i], e_bit[i + 4] = l_bit[16][i];
ASCII2Bin(e_bit, e_byte);
//按照表IP-1进行位变换
for(i = 0; i < 64; i++)
e_byte1[i] = e_byte[ip_1[i] - 1];
//得到最后的加密结果
Bin2ASCII(e_byte1, e_bit);
}
void DES::undes(const BYTE m_bit[8], const BYTE k_bit[8], BYTE e_bit[8])
{
//换位表IP
int ip[64] = {
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
};
//换位表IP_1
int ip_1[64] = {
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
};
//放大换位表
int e[48] = {
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
};
BYTE m_bit1[8] = {0};
BYTE m_byte[64] = {0};
BYTE m_byte1[64] = {0};
BYTE key_n[16][8] = {0};
BYTE l_bit[17][8] = {0};
BYTE r_bit[17][8] = {0};
BYTE e_byte[64] = {0};
BYTE e_byte1[64] = {0};
BYTE l_byte[64] = {0};
BYTE l_byte1[64] = {0};
int i = 0, j = 0;
//根据密钥生成16个子密钥
GenSubKey(k_bit, key_n);
//将待加密字串变换成01串
ASCII2Bin(m_bit, m_byte);
//按照ip表对待加密字串进行位变换
for(i = 0; i < 64; i++)
m_byte1[i] = m_byte[ip[i] - 1];
//位变换后的待加密字串
Bin2ASCII(m_byte1, m_bit1);
//将位变换后的待加密字串分成两组，分别为前4字节R和后4字节L，作为迭代的基础（第16次迭代）
for(i = 0; i < 4; i++)
r_bit[16][i] = m_bit1[i], l_bit[16][i] = m_bit1[i + 4];
//16次迭代运算
for(i = 16; i > 0; i--)
{
//L的上一次的迭代结果作为R的当前次迭代结果
for(j = 0; j < 4; j++)
r_bit[i-1][j] = l_bit[i][j];
ASCII2Bin(l_bit[i], l_byte);
//将L的上一次迭代结果按E表进行位扩展得到48位中间结果 -/{FG.bpR;
for(j = 0; j < 48; j++)
l_byte1[j] = l_byte[e[j] - 1];
Bin2ASCII(l_byte1, l_bit[i]);
//与第I-1个子密钥进行异或运算
for(j = 0; j < 6; j++)
l_bit[i][j] = l_bit[i][j] ^ key_n[i-1][j];
//进行S选择，得到32位中间结果
SReplace(l_bit[i]);
//结果与R的上次迭代结果异或得到L的此次迭代结果
for(j = 0; j < 4; j++)
{
l_bit[i-1][j] = r_bit[i][j] ^ l_bit[i][j];
}
}
//组合最终迭代结果
for(i = 0; i < 4; i++)
e_bit[i] = l_bit[0][i], e_bit[i + 4] = r_bit[0][i];
ASCII2Bin(e_bit, e_byte);
//按照表IP-1进行位变换
for(i = 0; i < 64; i++)
e_byte1[i] = e_byte[ip_1[i] - 1];
//得到最后的结果
Bin2ASCII(e_byte1, e_bit);
}
/*
* SReplace 函数说明：
* S选择
* 返回：
* 无
* 参数：
* BYTE s_bit[8] 输入暨选择后的输出
*/
void DES::SReplace(BYTE s_bit[8])
{
int p[32] = {
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
};
BYTE s[][4][16] ={
{
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
},
{
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
},
{
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
},
{
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
},
{
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,
},
{
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
},
{
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
},
{
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
}
};
BYTE s_byte[64] = {0};
BYTE s_byte1[64] = {0};
BYTE row = 0, col = 0;
BYTE s_out_bit[8] = {0};
//转成二进制字符串处理
ASCII2Bin(s_bit, s_byte);
for(int i = 0; i < 8; i++)
{
//0、5位为row，1、2、3、4位为col，在S表中选择一个八位的数
row = s_byte[i * 6] * 2 + s_byte[i * 6 + 5];
col = s_byte[i * 6 + 1] * 8 + s_byte[i * 6 + 2] * 4 + s_byte[i * 6 + 3] * 2 + s_byte[i * 6 + 4];
s_out_bit[i] = s[i][row][col];
}
//将八个选择的八位数据压缩表示
s_out_bit[0] = (s_out_bit[0] << 4) + s_out_bit[1];
s_out_bit[1] = (s_out_bit[2] << 4) + s_out_bit[3];
s_out_bit[2] = (s_out_bit[4] << 4) + s_out_bit[5];
s_out_bit[3] = (s_out_bit[6] << 4) + s_out_bit[7];
//转成二进制字符串处理
ASCII2Bin(s_out_bit, s_byte);
//换位 kgb.obol.A
for(i = 0; i < 32; i++)
s_byte1[i] = s_byte[p[i] - 1];
//生成最后结果
Bin2ASCII(s_byte1, s_bit);
}
#endif
DES.cpp
#include "DES.h"
#include
#include
void main()
{
DES temp;
char* encode = "abcdefg123400000005";
char result[40];
char result2[40];
const unsigned char key[8]={1,2,3,4,5,6,7,8};
temp.CDesEnter((unsigned char*)encode,(unsigned char*)result,19,key,0);
temp.CDesEnter((unsigned char*)result,(unsigned char*)result2,40,key,1);
printf("result=%s",result2);
}
