C++实现DES加密解密
DES实验要求
实验目的
实现电子本模式（ECB）和密码分组链接模式（CBC）的DES算法。
实验要求
- 指定明文文件、密钥文件、初始化向量文件的位置和名称，加密的操作模式以及加密完成后密文文件的位置和名称。
- 加密时先分别从指定的明文文件、密钥文件和初始化向量文件中读取有关信息，然后按ECB和CBC操作模式分别进行加密，最后将密文（用16进制表示）写入指定的密文文件。解密类似。
- 统一将文件名命名如下：
明文文件名：des_messages.txt
密钥文件名：des_key.txt
密文文件名：des_secret.txt
解密结果文件名：des_decrypted.txt
初始化向量文件：des_iv.txt - 如果一个分组不足64bit，低位补0。
代码
DES.h
#ifndef DESH
#define DESH
#include <string>
using namespace std;
/*DES.h: declaration of the TDES、TBase64、TBase64DES class. */
/* TDES类说明：该类是DES和3DES算法类 */
class CDES {
public:
CDES();
virtual ~CDES();
static char* HexToStr(string s);
static string StrToHex(char* bytes, int bytelength);
static bool EnCode(); //des加密
static bool DeCode(); //des解密
protected:
typedef bool(*PSubKey)[16][48];
//计算并填充子密钥到SubKey数据中
static void SetSubKey(PSubKey pSubKey, const unsigned char Key[8]);
//DES单元运算
static void DES(unsigned char Out[8], const unsigned char In[8], const PSubKey pSubKey, bool Type);
/* 补足8位数据
* Description: 根据协议对加密前的数据进行填充
* @param nType: 类型：PAD类型
* @param In: 数据串指针
* @param Out: 填充输出串指针
* @param datalen: 数据的长度
* @param padlen: (in,out)输出buffer的长度，填充后的长度
* @return true--成功；false--失败；
*/
static bool RunPad(bool bType, int nType, const unsigned char* In, unsigned datalen, unsigned char* Out, unsigned& padlen);
/* 执行DES算法对文本加解密
* Description : 执行DES算法对文本加解密
* @param bType : 类型：加密ENCRYPT，解密DECRYPT
* @param bMode : 模式：ECB,CBC
* @param In : 待加密串指针
* @param Out : 待输出串指针
* @param datalen : 待加密串的长度，同时Out的缓冲区大小应大于或者等于datalen
* @param Key : 密钥(可为8位,16位,24位)支持3密钥
* @param keylen : 密钥长度，多出24位部分将被自动裁减
* @return true--成功；false--失败；
*/
static bool RunDES(bool bType, bool bMode, int PaddingMode, const unsigned char* IV, const unsigned char* In,
unsigned char* Out, unsigned datalen, const unsigned char* Key, unsigned keylen);
private:
/*static int hexCharToInt(char c);*/
enum {
ENCRYPT = 0, // 加密
DECRYPT, // 解密
};
enum {
ECB = 0, // ECB模式
CBC // CBC模式
};
enum {
PAD_ISO_1 = 0, // ISO_1填充：数据长度不足8比特的倍数，以0x00补足，如果为8比特的倍数，补8个0x00
};
};
#endif
DES.cpp
#include "DES.h"
#include "memory.h"
#include <iostream>
#include<fstream>
using namespace std;
/* initial permutation IP */
const char IP_Table[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
};
/* final permutation IP^-1 */
const char IPR_Table[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
};
/* expansion operation matrix */
const char E_Table[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
};
/* 32-bit permutation function P used on the output of the S-boxes */
const char P_Table[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
};
/* permuted choice table (key) */
const char PC1_Table[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
};
/* permuted choice key (table) */
const char PC2_Table[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
};
/* number left rotations of pc1 */
const char LOOP_Table[16] = { 1,1,2,2,2,2,2,2,1,2,2,2,2,2,2,1 };
/* The (in)famous S-boxes */
const char S_Box[8][4][16] = {
// 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
};
CDES::CDES() {}
CDES::~CDES() {}
/*十六进制字符串转化为ASCII字符串 每2位十六进制字符 = 8 bit = 1 ASCII字符*/
char * CDES::HexToStr(string s) {
int temp = 0;
int len = s.length();
char * result = new char[len / 2 + 1];
for (int i = 0; i < len; i += 2) {
for (int j = 0; j < 2; j++) {
if (s[i + j] >= '0' && s[i + j] <= '9') {
temp += (s[i + j] - '0') << (4 * (1 - j));
}
else if (s[i + j] >= 'A' && s[i + j] <= 'F') {
temp += (s[i + j] - 'A' + 10) << (4 * (1 - j));
}
else if (s[i + j] >= 'a'&& s[i + j] <= 'f') {
temp += (s[i + j] - 'a' + 10) << (4 * (1 - j));
}
}
result[i / 2] = (char)temp;
temp = 0;
}
result[len / 2] = '\0';
return result;
}
/*字符串转化为十六进制 一个字符 = 一个ASCII码 = 两位十六进制数 */
string CDES::StrToHex(char* bytes, int bytelength) {
string str("");
string str2("0123456789ABCDEF");
for (int i = 0; i < bytelength; i++) {
int b;
b = 0x0f & (bytes[i] >> 4);
str.append(1, str2.at(b)); //向str后追加1个str2.at(b)
b = 0x0f & bytes[i];
str.append(1, str2.at(b));
}
return str;
}
/*将ascii字符转化为相对整数
int CDES::hexCharToInt(char c) {
if (c >= '0' && c <= '9') return (c - '0'); //比如字符"6"即对应整数6
if (c >= 'A' && c <= 'F') return (c - 'A' + 10); //字母返回 其在字母表中相对位置+10（？？？？？？？）
if (c >= 'a' && c <= 'f') return (c - 'a' + 10);
return 0;
}*/
/*加密入口*/
bool CDES::EnCode() {
string msg, sKey, filepath, IV = "";
int mode; //工作模式 ECB or CBC
//读入明文并打印
cout << "\nEnter the path of the plaintext file" << endl;
cout << "> ";
cin >> filepath;
ifstream msgFile(filepath);
if (!msgFile.is_open()) {
cout << "Can not open the file!" << endl;
return false;
}
getline(msgFile, msg);
cout << "Message: " << msg << endl;
msgFile.close();
//读入密钥并打印
cout << "\nEnter the path of the key file" << endl;
cout << "> ";
cin >> filepath;
ifstream keyFile(filepath);
if (!keyFile.is_open()) {
cout << "Can not open the file!" << endl;
return false;
}
keyFile >> sKey;
cout << "Key: " << sKey << endl;
sKey = HexToStr(sKey);
keyFile.close();
/*加密模式*/
cout << "\nEnter encryption mode: [0]ECB, [1]CBC" << endl;
cout << "> ";
cin >> mode;
while (mode != 0 && mode != 1) {
cout << "Invalid input! Please re-enter!" << endl;
cout << ">";
cin >> mode;
}
if (mode == CBC) {
//读入IV并打印
cout << "\nEnter the path of the IV file" << endl;
cout << "> ";
cin >> filepath;
ifstream IVFile(filepath);
if (!IVFile.is_open()) {
cout << "Can not open the file!" << endl;
return false;
}
IVFile >> IV;
cout << "IV: " << IV << endl;
/ATTENTION
IV = HexToStr(IV);
IVFile.close();
}
unsigned char buff[1024] = { 0 };
CDES::RunDES(CDES::ENCRYPT, mode, CDES::PAD_ISO_1, (const unsigned char*)IV.c_str(), (const unsigned char*)msg.c_str(), buff, strlen(msg.c_str()), (const unsigned char*)sKey.c_str(), strlen(sKey.c_str()));
string restr = StrToHex((char*)buff, strlen((char*)buff));
cout << "Cipher: " << restr << endl;
cout << "\nEnter the file path to save ciphertext" << endl;
cout << "> ";
cin >> filepath;
ofstream cipherFile(filepath);
if (!cin || !cipherFile.is_open())
return false;
cipherFile << restr;
cout << "Write successfully!" << endl;
cipherFile.close();
return true;
}
/*解密入口*/
bool CDES::DeCode() {
string ciph, sKey, filepath, IV;
//读入密文并打印
cout << "\nEnter the path of the ciphertext file" << endl;
cout << "> ";
cin >> filepath;
ifstream ciphFile(filepath);
if (!ciphFile.is_open()) {
cout << "Can not open the file!" << endl;
return false;
}
ciphFile >> ciph;
cout << "Cipher: " << ciph << endl;
ciphFile.close();
//读入密钥并打印
cout << "\nEnter the path of the key file" << endl;
cout << "> ";
cin >> filepath;
ifstream keyFile(filepath);
if (!keyFile.is_open()) {
cout << "Can not open the file!" << endl;
return false;
}
keyFile >> sKey;
cout << "Key: " << sKey << endl;
LOOK!!!!!!!!!!!!HERE!!!!!!!!!!
sKey = HexToStr(sKey);
keyFile.close();
/*解密模式*/
cout << "\nEnter encryption mode: [0]ECB, [1]CBC" << endl;
cout << "> ";
int mode;
cin >> mode;
while (mode != 0 && mode != 1) {
cout << "Invalid input! Please re-enter!" << endl;
cout << ">";
cin >> mode;
}
if (mode == CBC) {
//读入IV并打印
cout << "\nEnter the path of the IV file" << endl;
cout << "> ";
cin >> filepath;
ifstream IVFile(filepath);
if (!IVFile.is_open()) {
cout << "Can not open the file!" << endl;
return false;
}
IVFile >> IV;
cout << "IV: " << IV << endl;
/ATTENTION
IV = HexToStr(IV);
IVFile.close();
}
unsigned char ch[1024] = { 0 };
char* c = HexToStr(ciph);
char Out[1024] = { 0 };
CDES::RunDES(CDES::DECRYPT, mode, CDES::PAD_ISO_1, (const unsigned char*)IV.c_str(), (const unsigned char*)c, (unsigned char*)Out, strlen(ciph.c_str()), (const unsigned char*)sKey.c_str(), strlen(sKey.c_str()));
string decrypted = Out;
cout << "Decrypted: " << decrypted << endl;
cout << "\nEnter the file path to save decrypted text" << endl;
cout << "> ";
cin >> filepath;
ofstream decryptedFile(filepath);
if (!cin || !decryptedFile.is_open())
return false;
decryptedFile << decrypted;
cout << "Write successfully!" << endl;
decryptedFile.close();
return true;
}
/*
函 数 名 称: ByteToBit
功 能 描 述： 把BYTE转化为Bit流
参 数 说 明： Out: 输出的Bit流[in][out]
In: 输入的BYTE流[in]
bits: Bit流的长度[in]
*/
static void ByteToBit(bool *Out, const unsigned char *In, int bits) {
for (int i = 0; i < bits; ++i)
Out[i] = (In[i >> 3] >> (7 - i & 7)) & 1;
}
/*
函 数 名 称: BitToByte
功 能 描 述： 把Bit转化为Byte流
参 数 说 明： Out: 输出的BYTE流[in][out]
In: 输入的Bit流[in]
bits: Bit流的长度[in]
*/
static void BitToByte(unsigned char *Out, const bool *In, int bits) {
memset(Out, 0, bits >> 3);
for (int i = 0; i < bits; ++i)
Out[i >> 3] |= In[i] << (7 - i & 7);
}
/*
函 数 名 称: RotateL
功 能 描 述： 把BIT流按位向左迭代
参 数 说 明： In: 输入的Bit流[in]
len: Bit流的长度[in]
loop: 向左迭代的长度
*/
static void RotateL(bool *In, int len, int loop) {
bool Tmp[256];
memcpy(Tmp, In, loop);
memcpy(In, In + loop, len - loop);
memcpy(In + len - loop, Tmp, loop);
}
/*
函 数 名 称: Xor
功 能 描 述： 把两个Bit流进行异或
参 数 说 明： InA: 输入的Bit流[in][out]
InB: 输入的Bit流[in]
loop: Bit流的长度
*/
static void Xor(bool *InA, const bool *InB, int len) {
for (int i = 0; i < len; ++i)
InA[i] ^= InB[i];
}
/*
函 数 名 称: Transform
功 能 描 述： 把两个Bit流按表进行位转化
参 数 说 明： Out: 输出的Bit流[out]
In: 输入的Bit流[in]
Table: 转化需要的表指针
len: 转化表的长度
*/
static void Transform(bool *Out, bool *In, const char *Table, int len) {
bool Tmp[256];
for (int i = 0; i < len; ++i)
Tmp[i] = In[Table[i] - 1];
memcpy(Out, Tmp, len);
}
/*
函 数 名 称: S_func
功 能 描 述： 实现数据加密S BOX模块
参 数 说 明： Out: 输出的32Bit[out]
In: 输入的48Bit[in]
*/
static void S_func(bool Out[32], const bool In[48]) {
for (char i = 0, j, k; i < 8; ++i, In += 6, Out += 4)
{
j = (In[0] << 1) + In[5];
k = (In[1] << 3) + (In[2] << 2) + (In[3] << 1) + In[4]; //组织SID下标
for (int l = 0; l < 4; ++l) //把相应4bit赋值
Out[l] = (S_Box[i][j][k] >> (3 - l)) & 1;
}
}
/*
函 数 名 称: F_func
功 能 描 述： 实现数据加密到输出P
参 数 说 明： Out: 输出的32Bit[out]
In: 输入的48Bit[in]
*/
static void F_func(bool In[32], const bool Ki[48]) {
bool MR[48];
Transform(MR, In, E_Table, 48);
Xor(MR, Ki, 48);
S_func(In, MR);
Transform(In, In, P_Table, 32);
}
bool CDES::RunDES(bool bType, bool bMode, int PaddingMode, const unsigned char* Iv, const unsigned char* In,
unsigned char* Out, unsigned datalen, const unsigned char* Key, unsigned keylen)
{
memset(Out, 0x00, strlen((const char*)Out));
unsigned char* outbuf = Out;
/*判断输入合法性*/
if (!(outbuf && Key && keylen >= 8)) // 空字符串加密的时候In和datalen都为0,应该去掉此判断
return false;
unsigned char* inbuf = new unsigned char[datalen + 8]{ 0 };
memcpy(inbuf, In, datalen);
unsigned padlen = datalen;
/* 根据填充模式填充 */
if (!RunPad(bType, PaddingMode, In, datalen, inbuf, padlen)) {
delete[]inbuf;
inbuf = NULL;
return false;
}
unsigned char* tempBuf = inbuf;
bool m_SubKey[3][16][48]; //密钥
/*构造并生成SubKeys */
unsigned char nKey = (keylen >> 3) >= 3 ? 3 : (keylen >> 3);
for (int i = 0; i < nKey; i++) {
SetSubKey(&m_SubKey[i], &Key[i << 3]);
}
/*ECB模式*/
if (bMode == ECB) {
if (nKey == 1) { //单Key
int j = padlen >> 3;
for (int i = 0, j = padlen >> 3; i < j; ++i, outbuf += 8, tempBuf += 8)
DES(outbuf, tempBuf, &m_SubKey[0], bType);
}
/*不要轻易注释这里 ！！！*/
else if (nKey == 2) { //3DES 2Key
for (int i = 0, j = padlen >> 3; i < j; ++i, outbuf += 8, tempBuf += 8) {
DES(outbuf, tempBuf, &m_SubKey[0], bType);
DES(outbuf, outbuf, &m_SubKey[1], !bType);
DES(outbuf, outbuf, &m_SubKey[0], bType);
}
}
else { //3DES 3Key
for (int i = 0, j = padlen >> 3; i < j; ++i, outbuf += 8, tempBuf += 8) {
DES(outbuf, tempBuf, &m_SubKey[bType ? 2 : 0], bType);
DES(outbuf, outbuf, &m_SubKey[1], !bType);
DES(outbuf, outbuf, &m_SubKey[bType ? 0 : 2], bType);
}
}
}
/*CBC模式*/
else {
unsigned char cvec[8] = ""; // 扭转向量
unsigned char cvin[8] = ""; // 中间变量
memcpy(cvec, Iv, 8);
for (int i = 0, j = padlen >> 3; i < j; ++i, outbuf += 8, tempBuf += 8) {
if (bType == CDES::ENCRYPT) {
for (int j = 0; j < 8; ++j) //将输入与扭转变量异或
cvin[j] = tempBuf[j] ^ cvec[j];
}
else {
memcpy(cvin, tempBuf, 8);
}
DES(outbuf, cvin, &m_SubKey[0], bType);
if (bType == CDES::ENCRYPT) {
memcpy(cvec, outbuf, 8); //将输出设定为扭转变量
}
else {
for (int j = 0; j < 8; ++j) //将输出与扭转变量异或
outbuf[j] = outbuf[j] ^ cvec[j];
memcpy(cvec, cvin, 8); //将输入设定为扭转变量
}
}
}
if (inbuf) {
delete[]inbuf;
inbuf = NULL;
}
if (bType == CDES::DECRYPT) {
if (PaddingMode == PAD_ISO_1) {
//待补充
}
}
return true;
}
/*
函 数 名 称: RunPad
功 能 描 述： 根据协议对加密前的数据进行填充
参 数 说 明： bType :类型：PAD类型
In :数据串指针
Out :填充输出串指针
datalen :数据的长度
padlen :(in,out)输出buffer的长度，填充后的长度
返回值 说明： bool :是否填充成功
*/
bool CDES::RunPad(bool bType, int nType, const unsigned char* In, unsigned datalen, unsigned char* Out, unsigned& padlen) {
if (nType < PAD_ISO_1) //|| nType > PAD_PKCS_7)
return false;
if (In == NULL || datalen < 0 || Out == NULL)
return false;
int res = (datalen & 0x07); //得到datalen的低三位 也就是对8取余
if (bType == CDES::DECRYPT) {
// padlen = datalen;
padlen = datalen / 2; //因为是十六进制字符串的密文（例如：A的ascii是65，写成十六进制是41，保存在密文文件里边是"41"，两个char），所以两个密文文件的字符对应一个真正的Ascii字符
memcpy(Out, In, datalen);
return true;
}
memcpy(Out, In, datalen);
padlen = datalen;
if (res != 0) {
padlen += (8 - res);//使成为8的倍数
if (nType == PAD_ISO_1) {
memset(Out + datalen, 0x00, 8 - res);
}
}
return true;
}
/*计算并填充子密钥到SubKey数据中 */
void CDES::SetSubKey(PSubKey pSubKey, const unsigned char Key[8]) {
bool K[64], *KL = &K[0], *KR = &K[28];
ByteToBit(K, Key, 64);
Transform(K, K, PC1_Table, 56);
for (int i = 0; i < 16; ++i) {
RotateL(KL, 28, LOOP_Table[i]);
RotateL(KR, 28, LOOP_Table[i]);
Transform((*pSubKey)[i], K, PC2_Table, 48);
}
}
/* DES单元运算 */
void CDES::DES(unsigned char Out[8], const unsigned char In[8], const PSubKey pSubKey, bool Type) {
bool M[64], tmp[32], *Li = &M[0], *Ri = &M[32];
ByteToBit(M, In, 64);
Transform(M, M, IP_Table, 64);
if (Type == ENCRYPT) {
for (int i = 0; i < 16; ++i) {
memcpy(tmp, Ri, 32); //Ri[i-1] 保存
F_func(Ri, (*pSubKey)[i]); //Ri[i-1]经过转化和SBox输出为P
Xor(Ri, Li, 32); //Ri[i] = P XOR Li[i-1]
memcpy(Li, tmp, 32); //Li[i] = Ri[i-1]
}
}
else {
for (int i = 15; i >= 0; --i) {
memcpy(tmp, Ri, 32); //Ri[i-1] 保存
F_func(Ri, (*pSubKey)[i]); //Ri[i-1]经过转化和SBox输出为P
Xor(Ri, Li, 32); //Ri[i] = P XOR Li[i-1]
memcpy(Li, tmp, 32); //Li[i] = Ri[i-1]
}
}
RotateL(M, 64, 32); //Ri与Li换位重组M
Transform(M, M, IPR_Table, 64); //最后结果进行转化
BitToByte(Out, M, 64); //组织成字符
}
int main() {
while (true) {
cout << "\n\n";
cout << "********** Welcome to DES encoder **********" << endl;
cout << "[0] Quit" << endl;
cout << "[1] DES encode" << endl;
cout << "[2] DES decode" << endl;
cout << "Input your choice" << endl;
cout << "> ";
int choice;
cin >> choice;
while (choice != 0 && choice != 1 && choice != 2) {
cout << "Invalid input! Please re-enter!" << endl;
cout << "> ";
cin >> choice;
}
CDES cdes;
if (choice == 1) {
if (!cdes.EnCode()) {
cout << "Encryption failed! " << endl;
return 0;
}
}
else if (choice == 2) {
if (!cdes.DeCode()) {
cout << "Decryption failed! " << endl;
return 0;
}
}
else { break; }
}
return 0;
system("pause");
}
运行结果
