大哥，小弟求个C++ des加密的小程序，要可以运行的啊
int DES(
unsigned char *bufferin,
unsigned char *bufferout,
unsigned char *key,
long mode)
{
//密钥变换为56字节(去掉校验位)
static unsigned char pc1[56] = {
56, 48, 40, 32, 24, 16, 8,
0, 57, 49, 41, 33, 25, 17,
9, 1, 58, 50, 42, 34, 26,
18, 10, 2, 59, 51, 43, 35,
62, 54, 46, 38, 30, 22, 14,
6, 61, 53, 45, 37, 29, 21,
13, 5, 60, 52, 44, 36, 28,
20, 12, 4, 27, 19, 11, 3 };
//56字节变换为48 字节(数据压缩)
static unsigned char pc2[48] = {
13, 16, 10, 23, 0, 4,
2, 27, 14, 5, 20, 9,
22, 18, 11, 3, 25, 7,
15, 6, 26, 19, 12, 1,
40, 51, 30, 36, 46, 54,
29, 39, 50, 44, 32, 47,
43, 48, 38, 55, 33, 52,
45, 41, 49, 35, 28, 31 };
//32字节变换为48字节(数据扩展)
static unsigned char exp[48] = {
31, 0, 1, 2, 3, 4,
3, 4, 5, 6, 7, 8,
7, 8, 9, 10, 11, 12,
11, 12, 13, 14, 15, 16,
15, 16, 17, 18, 19, 20,
19, 20, 21, 22, 23, 24,
23, 24, 25, 26, 27, 28,
27, 28, 29, 30, 31, 0 };
//64位数据IP(Initial Permutation)变换表
static unsigned char ip[64] = {
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,
56, 48, 40, 32, 24, 16, 8, 0,
58, 50, 42, 34, 26, 18, 10, 2,
60, 52, 44, 36, 28, 20, 12, 4,
62, 54, 46, 38, 30, 22, 14, 6 };
//数据逆置换(Final Permutation)
static unsigned char ip_1[64] = {
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,
32, 0, 40, 8, 48, 16, 56, 24 };
//Permutation P
static unsigned char pp[32] = {
15, 6, 19, 20,
28, 11, 27, 16,
0, 14, 22, 25,
4, 17, 30, 9,
1, 7, 23, 13,
31, 26, 2, 8,
18, 12, 29, 5,
21, 10, 3, 24 };
/* INITIALIZE THE TABLES */
/* Table - s1 */
static unsigned char s1[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 };
/* Table - s2 */
static unsigned char s2[4][16] = {
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 };
/* Table - s3 */
static unsigned char s3[4][16] = {
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 };
/* Table - s4 */
static unsigned char s4[4][16] = {
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 };
/* Table - s5 */
static unsigned char s5[4][16] = {
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 };
/* Table - s6 */
static unsigned char s6[4][16] = {
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 };
/* Table - s7 */
static unsigned char s7[4][16] = {
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 };
/* Table - s8 */
static unsigned char s8[4][16] = {
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 };
/* 密钥生成中的循环左移位的累计次数*/
static unsigned char totrot[] = {
1, 2, 4, 6, 8, 10, 12, 14, 15, 17, 19, 21, 23, 25, 27, 28 };
/*----------------------------------------------*/
//long mode = 1; //模式，1：加密，2：解密
//unsigned char bufferin[9], bufferout[9]; //明文，密文
/*----------------------------------------------*/
long i, j, k;
long rotshift; //密钥移位次数
//long keylen, buflen; //密钥长度,明文长度
unsigned char keybuf[65]; //密钥，密钥64字节缓冲区
unsigned char keyreal[57], keys[17][49]; //实际使用56字节密钥,48字节密钥数组
unsigned char srcbuf[65], dstbuf[65]; //明文，密文64字节缓冲区
unsigned char L[17][33], R[17][33], LR[65], RL[65]; //加密时临时数据左右两部分
unsigned char E[17][49]; //R数组的扩展数据
unsigned char B[9][7], BB[33], P[33]; //E和K异或后的缓冲数组
unsigned char C[17][29], D[17][29], CD[57]; //56字节密钥的左右两部分
unsigned char temp1, temp2, m, n, x;
//1.变换密钥
//密钥不足8字节则用0补足(或自定义)
//keylen = strlen((const char*)key);
//if(keylen<8)
// memset(key+keylen, 0, (8-keylen));
//将8字节密钥转换为64字节字串
for(i=0;i<8;i++)
{
j = *(key+i);
keybuf[8*i] = (j / 128) % 2;
keybuf[8*i+1] = (j / 64) % 2;
keybuf[8*i+2] = (j / 32) % 2;
keybuf[8*i+3] = (j / 16) % 2;
keybuf[8*i+4] = (j / 8) % 2;
keybuf[8*i+5] = (j / 4) % 2;
keybuf[8*i+6] = (j / 2) % 2;
keybuf[8*i+7] = (j / 1) % 2;
}
//根据pc1进行变换成56字节，去掉奇偶校验位
for(i=0;i<56;i++)
{
keyreal[i] = keybuf[pc1[i]];
}
//将56字节密钥分为左右两部分C[0],D[0]
for(i=0;i<28;i++)
{
C[0][i] = keyreal[i];
D[0][i] = keyreal[i+28];
}
//循环16次(i从1开始)
for(i=1;i<17;i++)
{
//根据加密或解密确定密钥顺序
if(mode) //加密
rotshift = totrot[i-1];
else //解密
rotshift = totrot[16-i];
//1)左移固定位数得到C[i]和D[i];
for(j=0;j<28;j++)
{
C[i][j] = C[0][j];
D[i][j] = D[0][j];
}
for(j=0;j<rotshift;j++)
{
temp1 = C[i][0];
temp2 = D[i][0];
for(k=0;k<27;k++)
{
C[i][k] = C[i][k+1];
D[i][k] = D[i][k+1];
}
C[i][27] = temp1;
D[i][27] = temp2;
}
//2)将C[i]D[i]用pc2化简为48位k[i];
for(j=0;j<28;j++)
{
CD[j] = C[i][j];
CD[j+28] = D[i][j];
}
for(j=0;j<48;j++)
{
keys[i][j] = CD[pc2[j]];
}
}
//2.数据处理
//若明文不足8字节则补0(或自定义)
//buflen = strlen((const char*)bufferin);
//if(buflen<8)
// memset(bufferin+buflen, 0, (8-buflen));
//将8字节数据转换为64字节字串
for(i=0;i<8;i++)
{
j = *(bufferin+i);
srcbuf[i*8] = (j / 128) % 2;
srcbuf[i*8+1] = (j / 64) % 2;
srcbuf[i*8+2] = (j / 32) % 2;
srcbuf[i*8+3] = (j / 16) % 2;
srcbuf[i*8+4] = (j / 8) % 2;
srcbuf[i*8+5] = (j / 4) % 2;
srcbuf[i*8+6] = (j / 2) % 2;
srcbuf[i*8+7] = (j / 1) % 2;
}
//将srcbuf按ip进行变换
for(i=0;i<64;i++)
LR[i] = srcbuf[ip[i]];
//将64字节数据转换为两部分L[0],R[0]
for(i=0;i<32;i++)
{
L[0][i] = LR[i];
R[0][i] = LR[i+32];
}
//循环16次(i从1开始)，用密钥加密数据
for(i=1;i<17;i++)
{
//1)将32位的R[i-1]按exp扩展为48位的E[i-1];
for(j=0;j<48;j++)
{
E[i-1][j] = R[i-1][exp[j]];
}
//2)异或E[i-1]和K[i];
for(j=0;j<48;j++)
{
keys[i][j] = keys[i][j] ^ E[i-1][j];
}
//3)将异或结果分为8个6位长的部分B[8]
for(j=0;j<8;j++)
{
B[j][0] = keys[i][j*6];
B[j][1] = keys[i][j*6+1];
B[j][2] = keys[i][j*6+2];
B[j][3] = keys[i][j*6+3];
B[j][4] = keys[i][j*6+4];
B[j][5] = keys[i][j*6+5];
}
//4)循环用S表替换(j从1开始)
for(j=0;j<8;j++)
{
//a)B[j]第1位和第6位组合为M，作为S[j]的行号
m = 2 * B[j][0] + B[j][5];
//b)B[j]第2到5位组合为N，作为S[j]的列号
n = 2 * (2 * (2 * B[j][1] + B[j][2]) + B[j][3]) + B[j][4];
//c)用S[j][M][N]来取代B[j]
switch(j)
{
case 0:
x = s1[m][n];
break;
case 1:
x = s2[m][n];
break;
case 2:
x = s3[m][n];
break;
case 3:
x = s4[m][n];
break;
case 4:
x = s5[m][n];
break;
case 5:
x = s6[m][n];
break;
case 6:
x = s7[m][n];
break;
case 7:
x = s8[m][n];
break;
}
BB[j*4] = (x / 8) % 2;
BB[j*4 + 1] = (x / 4) % 2;
BB[j*4 + 2] = (x / 2) % 2;
BB[j*4 + 3] = (x / 1) % 2;
}
//5)将B[1]到B[8]按P组合得到p
for(j=0;j<32;j++)
{
P[j] = BB[pp[j]];
}
//6)R[i] = p xor L[i-1];L[i] = R[i-1];
for(j=0;j<32;j++)
{
R[i][j] = P[j] ^ L[i-1][j];
L[i][j] = R[i-1][j];
}
}
//3.组合变换后的R[16]L[16]按ip_1变换得到最后结果
for(i=0;i<32;i++)
{
RL[i] = R[16][i];
RL[i+32] = L[16][i];
}
for(i=0;i<64;i++)
{
dstbuf[i] = RL[ip_1[i]];
}
//将64字节数据转换为8字节
for (i = 0; i < 8; i++)
{
*(bufferout + i) = 0x00;
for (k = 0; k < 7; k++)
*(bufferout + i) = ((*(bufferout + i)) + dstbuf[8*i+k]) * 2;
*(bufferout + i) = *(bufferout + i) + dstbuf[8*i+7];
}
return 0;
}
有点长哈O(∩_∩)O哈！
我有代码
这是我们老师给的DES算法，肯定没问题，现在main()函数是空的，只要根据自己的需要将main（）函数再填充一下就能运行，可以对文件及文本加密、解密,可能由于百度回答问题的文本框有些小，有些本来在同一行代码的可能分到了两行，如果有这种问题，自己再调一下吧#include <string.h>
#include "stdio.h"
#include "memory.h"
#include "time.h"
#include "stdlib.h"
#define PLAIN_FILE_OPEN_ERROR -1
#define KEY_FILE_OPEN_ERROR -2
#define CIPHER_FILE_OPEN_ERROR -3
#define OK 1
typedef char ElemType;
/*初始置换表IP*/
int IP_Table[64] = { 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,
56,48,40,32,24,16,8,0,
58,50,42,34,26,18,10,2,
60,52,44,36,28,20,12,4,
62,54,46,38,30,22,14,6};
/*逆初始置换表IP^-1*/
int IP_1_Table[64] = {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,
32,0,40,8,48,16,56,24};
/*扩充置换表E*/
int E_Table[48] = {31, 0, 1, 2, 3, 4,
3, 4, 5, 6, 7, 8,
7, 8,9,10,11,12,
11,12,13,14,15,16,
15,16,17,18,19,20,
19,20,21,22,23,24,
23,24,25,26,27,28,
27,28,29,30,31, 0};
/*置换函数P*/
int P_Table[32] = {15,6,19,20,28,11,27,16,
0,14,22,25,4,17,30,9,
1,7,23,13,31,26,2,8,
18,12,29,5,21,10,3,24};
/*S盒*/
int S[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}}};
/*置换选择1*/
int PC_1[56] = {56,48,40,32,24,16,8,
0,57,49,41,33,25,17,
9,1,58,50,42,34,26,
18,10,2,59,51,43,35,
62,54,46,38,30,22,14,
6,61,53,45,37,29,21,
13,5,60,52,44,36,28,
20,12,4,27,19,11,3};
/*置换选择2*/
int PC_2[48] = {13,16,10,23,0,4,2,27,
14,5,20,9,22,18,11,3,
25,7,15,6,26,19,12,1,
40,51,30,36,46,54,29,39,
50,44,32,46,43,48,38,55,
33,52,45,41,49,35,28,31};
/*对左移次数的规定*/
int MOVE_TIMES[16] = {1,1,2,2,2,2,2,2,1,2,2,2,2,2,2,1};
int ByteToBit(ElemType ch,ElemType bit[8]);
int BitToByte(ElemType bit[8],ElemType *ch);
int Char8ToBit64(ElemType ch[8],ElemType bit[64]);
int Bit64ToChar8(ElemType bit[64],ElemType ch[8]);
int DES_MakeSubKeys(ElemType key[64],ElemType subKeys[16][48]);
int DES_PC1_Transform(ElemType key[64], ElemType tempbts[56]);
int DES_PC2_Transform(ElemType key[56], ElemType tempbts[48]);
int DES_ROL(ElemType data[56], int time);
int DES_IP_Transform(ElemType data[64]);
int DES_IP_1_Transform(ElemType data[64]);
int DES_E_Transform(ElemType data[48]);
int DES_P_Transform(ElemType data[32]);
int DES_SBOX(ElemType data[48]);
int DES_XOR(ElemType R[48], ElemType L[48],int count);
int DES_Swap(ElemType left[32],ElemType right[32]);
int DES_EncryptBlock(ElemType plainBlock[8], ElemType subKeys[16][48], ElemType cipherBlock[8]);
int DES_DecryptBlock(ElemType cipherBlock[8], ElemType subKeys[16][48], ElemType plainBlock[8]);
int DES_Encrypt(char *plainFile, char *keyStr,char *cipherFile);
int DES_Decrypt(char *cipherFile, char *keyStr,char *plainFile);
/*字节转换成二进制*/
int ByteToBit(ElemType ch, ElemType bit[8]){
int cnt;
for(cnt = 0;cnt < 8; cnt++){
*(bit+cnt) = (ch>>cnt)&1;
}
return 0;
}
/*二进制转换成字节*/
int BitToByte(ElemType bit[8],ElemType *ch){
int cnt;
for(cnt = 0;cnt < 8; cnt++){
*ch |= *(bit + cnt)<<cnt;
}
return 0;
}
/*将长度为8的字符串转为二进制位串*/
int Char8ToBit64(ElemType ch[8],ElemType bit[64]){
int cnt;
for(cnt = 0; cnt < 8; cnt++){
ByteToBit(*(ch+cnt),bit+(cnt<<3));
}
return 0;
}
/*将二进制位串转为长度为8的字符串*/
int Bit64ToChar8(ElemType bit[64],ElemType ch[8]){
int cnt;
memset(ch,0,8);
for(cnt = 0; cnt < 8; cnt++){
BitToByte(bit+(cnt<<3),ch+cnt);
}
return 0;
}
/*生成子密钥*/
int DES_MakeSubKeys(ElemType key[64],ElemType subKeys[16][48]){
ElemType temp[56];
int cnt;
DES_PC1_Transform(key,temp);/*PC1置换*/
for(cnt = 0; cnt < 16; cnt++){/*16轮跌代，产生16个子密钥*/
DES_ROL(temp,MOVE_TIMES[cnt]);/*循环左移*/
DES_PC2_Transform(temp,subKeys[cnt]);/*PC2置换，产生子密钥*/
}
return 0;
}
/*密钥置换1*/
int DES_PC1_Transform(ElemType key[64], ElemType tempbts[56]){
int cnt;
for(cnt = 0; cnt < 56; cnt++){
tempbts[cnt] = key[PC_1[cnt]];
}
return 0;
}
/*密钥置换2*/
int DES_PC2_Transform(ElemType key[56], ElemType tempbts[48]){
int cnt;
for(cnt = 0; cnt < 48; cnt++){
tempbts[cnt] = key[PC_2[cnt]];
}
return 0;
}
/*循环左移*/
int DES_ROL(ElemType data[56], int time){
ElemType temp[56];
/*保存将要循环移动到右边的位*/
memcpy(temp,data,time);
memcpy(temp+time,data+28,time);
/*前28位移动*/
memcpy(data,data+time,28-time);
memcpy(data+28-time,temp,time);
/*后28位移动*/
memcpy(data+28,data+28+time,28-time);
memcpy(data+56-time,temp+time,time);
return 0;
}
/*IP置换*/
int DES_IP_Transform(ElemType data[64]){
int cnt;
ElemType temp[64];
for(cnt = 0; cnt < 64; cnt++){
temp[cnt] = data[IP_Table[cnt]];
}
memcpy(data,temp,64);
return 0;
}
/*IP逆置换*/
int DES_IP_1_Transform(ElemType data[64]){
int cnt;
ElemType temp[64];
for(cnt = 0; cnt < 64; cnt++){
temp[cnt] = data[IP_1_Table[cnt]];
}
memcpy(data,temp,64);
return 0;
}
/*扩展置换*/
int DES_E_Transform(ElemType data[48]){
int cnt;
ElemType temp[48];
for(cnt = 0; cnt < 48; cnt++){
temp[cnt] = data[E_Table[cnt]];
}
memcpy(data,temp,48);
return 0;
}
/*P置换*/
int DES_P_Transform(ElemType data[32]){
int cnt;
ElemType temp[32];
for(cnt = 0; cnt < 32; cnt++){
temp[cnt] = data[P_Table[cnt]];
}
memcpy(data,temp,32);
return 0;
}
/*异或*/
int DES_XOR(ElemType R[48], ElemType L[48] ,int count){
int cnt;
for(cnt = 0; cnt < count; cnt++){
R[cnt] ^= L[cnt];
}
return 0;
}
/*S盒置换*/
int DES_SBOX(ElemType data[48]){
int cnt;
int line,row,output;
int cur1,cur2;
for(cnt = 0; cnt < 8; cnt++){
cur1 = cnt*6;
cur2 = cnt<<2;
/*计算在S盒中的行与列*/
line = (data[cur1]<<1) + data[cur1+5];
row = (data[cur1+1]<<3) + (data[cur1+2]<<2)
+ (data[cur1+3]<<1) + data[cur1+4];
output = S[cnt][line][row];
/*化为2进制*/
data[cur2] = (output&0X08)>>3;
data[cur2+1] = (output&0X04)>>2;
data[cur2+2] = (output&0X02)>>1;
data[cur2+3] = output&0x01;
}
return 0;
}
/*交换*/
int DES_Swap(ElemType left[32], ElemType right[32]){
ElemType temp[32];
memcpy(temp,left,32);
memcpy(left,right,32);
memcpy(right,temp,32);
return 0;
}
/*加密单个分组*/
int DES_EncryptBlock(ElemType plainBlock[8], ElemType subKeys[16][48], ElemType cipherBlock[8]){
ElemType plainBits[64];
ElemType copyRight[48];
int cnt;
Char8ToBit64(plainBlock,plainBits);
/*初始置换（IP置换）*/
DES_IP_Transform(plainBits);
/*16轮迭代*/
for(cnt = 0; cnt < 16; cnt++){
memcpy(copyRight,plainBits+32,32);
/*将右半部分进行扩展置换，从32位扩展到48位*/
DES_E_Transform(copyRight);
/*将右半部分与子密钥进行异或操作*/
DES_XOR(copyRight,subKeys[cnt],48);
/*异或结果进入S盒，输出32位结果*/
DES_SBOX(copyRight);
/*P置换*/
DES_P_Transform(copyRight);
/*将明文左半部分与右半部分进行异或*/
DES_XOR(plainBits,copyRight,32);
if(cnt != 15){
/*最终完成左右部的交换*/
DES_Swap(plainBits,plainBits+32);
}
}
/*逆初始置换（IP^1置换）*/
DES_IP_1_Transform(plainBits);
Bit64ToChar8(plainBits,cipherBlock);
return 0;
}
/*解密单个分组*/
int DES_DecryptBlock(ElemType cipherBlock[8], ElemType subKeys[16][48],ElemType plainBlock[8]){
ElemType cipherBits[64];
ElemType copyRight[48];
int cnt;
Char8ToBit64(cipherBlock,cipherBits);
/*初始置换（IP置换）*/
DES_IP_Transform(cipherBits);
/*16轮迭代*/
for(cnt = 15; cnt >= 0; cnt--){
memcpy(copyRight,cipherBits+32,32);
/*将右半部分进行扩展置换，从32位扩展到48位*/
DES_E_Transform(copyRight);
/*将右半部分与子密钥进行异或操作*/
DES_XOR(copyRight,subKeys[cnt],48);
/*异或结果进入S盒，输出32位结果*/
DES_SBOX(copyRight);
/*P置换*/
DES_P_Transform(copyRight);
/*将明文左半部分与右半部分进行异或*/
DES_XOR(cipherBits,copyRight,32);
if(cnt != 0){
/*最终完成左右部的交换*/
DES_Swap(cipherBits,cipherBits+32);
}
}
/*逆初始置换（IP^1置换）*/
DES_IP_1_Transform(cipherBits);
Bit64ToChar8(cipherBits,plainBlock);
return 0;
}
/*加密文本字符数组*/
int DES_Encrypt(char *plainText, int datalen,char *keyStr,char *cipherText){
int count = datalen;
int icount = count;
if ((count % 8) != 0)
icount = count+(8-(count % 8));
ElemType plainBlock[8],cipherBlock[8],keyBlock[8];
ElemType bKey[64];
ElemType subKeys[16][48];
/*设置密钥*/
memcpy(keyBlock,keyStr,8);
/*将密钥转换为二进制流*/
Char8ToBit64(keyBlock,bKey);
/*生成子密钥*/
DES_MakeSubKeys(bKey,subKeys);
char *pdata = plainText;
while(count>=8){
/*每次读8个字节，并返回成功读取的字节数*/
memcpy(plainBlock,pdata,8);
DES_EncryptBlock(plainBlock,subKeys,cipherBlock);
memcpy(cipherText,cipherBlock,8);
cipherText += 8;
pdata += 8;
count -= 8;
}
if(count){
/*填充*/
memcpy(plainBlock,pdata,count);
memset(plainBlock + count,'\0',7 - count);
/*最后一个字符保存包括最后一个字符在内的所填充的字符数量*/
plainBlock[7] = 8 - count;
DES_EncryptBlock(plainBlock,subKeys,cipherBlock);
memcpy(cipherText,cipherBlock,8);
}
return icount;
}
/*加密文件*/
int DES_Encrypt_File(char *plainFile, char *keyStr,char *cipherFile){
FILE *plain,*cipher;
int count;
ElemType plainBlock[8],cipherBlock[8],keyBlock[8];
ElemType bKey[64];
ElemType subKeys[16][48];
if((plain = fopen(plainFile,"rb")) == NULL){
return PLAIN_FILE_OPEN_ERROR;
}
if((cipher = fopen(cipherFile,"wb")) == NULL){
return CIPHER_FILE_OPEN_ERROR;
}
/*设置密钥*/
memcpy(keyBlock,keyStr,8);
/*将密钥转换为二进制流*/
Char8ToBit64(keyBlock,bKey);
/*生成子密钥*/
DES_MakeSubKeys(bKey,subKeys);
while(!feof(plain)){
/*每次读8个字节，并返回成功读取的字节数*/
if((count = fread(plainBlock,sizeof(char),8,plain)) == 8){
DES_EncryptBlock(plainBlock,subKeys,cipherBlock);
fwrite(cipherBlock,sizeof(char),8,cipher);
}
}
if(count){
/*填充*/
memset(plainBlock + count,'\0',7 - count);
/*最后一个字符保存包括最后一个字符在内的所填充的字符数量*/
plainBlock[7] = 8 - count;
DES_EncryptBlock(plainBlock,subKeys,cipherBlock);
fwrite(cipherBlock,sizeof(char),8,cipher);
}
fclose(plain);
fclose(cipher);
return OK;
}
/*解密文本字符数组*/
int DES_Decrypt(char *cipherText, int &cipherlen,char *keyStr,char **plainText){
int count = 0;
int times = 0;
ElemType plainBlock[8],cipherBlock[8],keyBlock[8];
ElemType bKey[64];
ElemType subKeys[16][48];
/*设置密钥*/
memcpy(keyBlock,keyStr,8);
/*将密钥转换为二进制流*/
Char8ToBit64(keyBlock,bKey);
/*生成子密钥*/
DES_MakeSubKeys(bKey,subKeys);
*plainText = new char[cipherlen+1];
memset(*plainText,0,cipherlen+1);
char *pdata = *plainText;
while(1){
/*密文的字节数一定是8的整数倍*/
memcpy(cipherBlock,cipherText,8);
DES_DecryptBlock(cipherBlock,subKeys,plainBlock);
times += 8;
if(times < cipherlen){
memcpy(pdata,plainBlock,8);
pdata = pdata + 8;
cipherText += 8;
}
else{
break;
}
}
/*判断末尾是否被填充*/
if(plainBlock[7] < 8){
for(count = 8 - plainBlock[7]; count < 7; count++){
if(plainBlock[count] != '\0'){
break;
}
}
}
if(count == 7){/*有填充*/
cipherlen -= plainBlock[7];
memcpy(pdata,plainBlock,8 - plainBlock[7]);
}
else{/*无填充*/
memcpy(pdata,plainBlock,8);
}
return OK;
}
/*解密文件*/
int DES_Decrypt_File(char *cipherFile, char *keyStr,char *plainFile){
FILE *plain, *cipher;
int count,times = 0;
long fileLen;
ElemType plainBlock[8],cipherBlock[8],keyBlock[8];
ElemType bKey[64];
ElemType subKeys[16][48];
if((cipher = fopen(cipherFile,"rb")) == NULL){
return CIPHER_FILE_OPEN_ERROR;
}
if((plain = fopen(plainFile,"wb")) == NULL){
return PLAIN_FILE_OPEN_ERROR;
}
/*设置密钥*/
memcpy(keyBlock,keyStr,8);
/*将密钥转换为二进制流*/
Char8ToBit64(keyBlock,bKey);
/*生成子密钥*/
DES_MakeSubKeys(bKey,subKeys);
/*取文件长度 */
fseek(cipher,0,SEEK_END);/*将文件指针置尾*/
fileLen = ftell(cipher); /*取文件指针当前位置*/
rewind(cipher); /*将文件指针重指向文件头*/
while(1){
/*密文的字节数一定是8的整数倍*/
fread(cipherBlock,sizeof(char),8,cipher);
DES_DecryptBlock(cipherBlock,subKeys,plainBlock);
times += 8;
if(times < fileLen){
fwrite(plainBlock,sizeof(char),8,plain);
}
else{
break;
}
}
/*判断末尾是否被填充*/
if(plainBlock[7] < 8){
for(count = 8 - plainBlock[7]; count < 7; count++){
if(plainBlock[count] != '\0'){
break;
}
}
}
if(count == 7){/*有填充*/
fwrite(plainBlock,sizeof(char),8 - plainBlock[7],plain);
}
else{/*无填充*/
fwrite(plainBlock,sizeof(char),8,plain);
}
fclose(plain);
fclose(cipher);
return OK;
}
void main()
{
}
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