des.cpp

des数据加密和解密算法

#include<stdio.h>
static unsigned char source2[8],k2[16][48];//保留密文、和子密钥
void  des(unsigned char *source,unsigned char * inkey, int flg) 
{ 
unsigned char  bufout[64], kwork[56], worka[48], kn[48], buffer[64], key[64],temp1, temp2;
int  valindex,dest[8];char shift1; 

int i,j,m; 
//s1-8 函数
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 }; 
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 }; 
 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 }; 
 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 }; 
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 }; 
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 }; 
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 }; 
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 }; 
static unsigned char  shift[16] = { 1, 1, 2, 2, 2, 2, 2, 2, 1, 2, 2, 2, 2, 2, 2, 1 }; //移位次数
//密码的二进制位变换
if(flg==1){
for (i = 0; i < 8; i++) {
j = *(inkey + i);	
key[8*i] = (j/128) % 2; //依次取每个字符,变为二进制位
key[8*i+1] = (j / 64) % 2; 
key[8*i+2] = (j / 32) % 2; 
key[8*i+3] = (j / 16) % 2; 
key[8*i+4] = (j / 8) % 2; 
key[8*i+5] = (j / 4) % 2; 
key[8*i+6] = (j / 2) % 2; 
key[8*i+7] = j % 2; 
} 
}
//原文的二进制变换
for (i = 0; i < 8; i++) { 
j = *(source + i);   //依次取每个字符,变为二进制位
buffer[8*i] = ((j) / 128) % 2; 
buffer[8*i+1] = (j / 64) % 2; 
buffer[8*i+2] = (j / 32) % 2; 
buffer[8*i+3] = (j / 16) % 2; 
buffer[8*i+4] = (j / 8) % 2; 
buffer[8*i+5] = (j / 4) % 2; 
buffer[8*i+6] = (j / 2) % 2; 
buffer[8*i+7] = j % 2; 
} 
//原文初始置换
bufout[ 0] = buffer[57]; 
bufout[ 1] = buffer[49]; 
bufout[ 2] = buffer[41]; 
bufout[ 3] = buffer[33]; 
bufout[ 4] = buffer[25]; 
bufout[ 5] = buffer[17]; 
bufout[ 6] = buffer[ 9]; 
bufout[ 7] = buffer[ 1]; 
bufout[ 8] = buffer[59]; 
bufout[ 9] = buffer[51]; 
bufout[10] = buffer[43]; 
bufout[11] = buffer[35]; 
bufout[12] = buffer[27]; 
bufout[13] = buffer[19]; 
bufout[14] = buffer[11]; 
bufout[15] = buffer[ 3]; 
bufout[16] = buffer[61]; 
bufout[17] = buffer[53]; 
bufout[18] = buffer[45]; 
bufout[19] = buffer[37]; 
bufout[20] = buffer[29]; 
bufout[21] = buffer[21]; 
bufout[22] = buffer[13]; 
bufout[23] = buffer[ 5]; 
bufout[24] = buffer[63]; 
bufout[25] = buffer[55]; 
bufout[26] = buffer[47]; 
bufout[27] = buffer[39]; 
bufout[28] = buffer[31]; 
bufout[29] = buffer[23]; 
bufout[30] = buffer[15]; 
bufout[31] = buffer[ 7]; 
bufout[32] = buffer[56]; 
bufout[33] = buffer[48]; 
bufout[34] = buffer[40]; 
bufout[35] = buffer[32]; 
bufout[36] = buffer[24]; 
bufout[37] = buffer[16]; 
bufout[38] = buffer[ 8]; 
bufout[39] = buffer[ 0]; 
bufout[40] = buffer[58]; 
bufout[41] = buffer[50]; 
bufout[42] = buffer[42]; 
bufout[43] = buffer[34]; 
bufout[44] = buffer[26]; 
bufout[45] = buffer[18]; 
bufout[46] = buffer[10]; 
bufout[47] = buffer[ 2]; 
bufout[48] = buffer[60]; 
bufout[49] = buffer[52]; 
bufout[50] = buffer[44]; 
bufout[51] = buffer[36]; 
bufout[52] = buffer[28]; 
bufout[53] = buffer[20]; 
bufout[54] = buffer[12]; 
bufout[55] = buffer[ 4]; 
bufout[56] = buffer[62]; 
bufout[57] = buffer[54]; 
bufout[58] = buffer[46]; 
bufout[59] = buffer[38]; 
bufout[60] = buffer[30]; 
bufout[61] = buffer[22]; 
bufout[62] = buffer[14]; 
bufout[63] = buffer[ 6]; 
if(flg==1){//密码缩小置换64---56
kwork[ 0] = key[56]; 
kwork[ 1] = key[48]; 
kwork[ 2] = key[40]; 
kwork[ 3] = key[32]; 
kwork[ 4] = key[24]; 
kwork[ 5] = key[16]; 
kwork[ 6] = key[ 8]; 
kwork[ 7] = key[ 0]; 
kwork[ 8] = key[57]; 
kwork[ 9] = key[49]; 
kwork[10] = key[41]; 
kwork[11] = key[33]; 
kwork[12] = key[25]; 
kwork[13] = key[17]; 
kwork[14] = key[ 9]; 
kwork[15] = key[ 1]; 
kwork[16] = key[58]; 
kwork[17] = key[50]; 
kwork[18] = key[42]; 
kwork[19] = key[34]; 
kwork[20] = key[26]; 
kwork[21] = key[18]; 
kwork[22] = key[10]; 
kwork[23] = key[ 2]; 
kwork[24] = key[59]; 
kwork[25] = key[51]; 
kwork[26] = key[43]; 
kwork[27] = key[35]; 
kwork[28] = key[62]; 
kwork[29] = key[54]; 
kwork[30] = key[46]; 
kwork[31] = key[38]; 
kwork[32] = key[30]; 
kwork[33] = key[22]; 
kwork[34] = key[14]; 
kwork[35] = key[ 6]; 
kwork[36] = key[61]; 
kwork[37] = key[53]; 
kwork[38] = key[45]; 
kwork[39] = key[37]; 
kwork[40] = key[29]; 
kwork[41] = key[21]; 
kwork[42] = key[13]; 
kwork[43] = key[ 5]; 
kwork[44] = key[60]; 
kwork[45] = key[52]; 
kwork[46] = key[44]; 
kwork[47] = key[36]; 
kwork[48] = key[28]; 
kwork[49] = key[20]; 
kwork[50] = key[12]; 
kwork[51] = key[ 4]; 
kwork[52] = key[27]; 
kwork[53] = key[19]; 
kwork[54] = key[11]; 
kwork[55] = key[ 3]; 
}
//16轮循环迭代
for (m = 1; m <=16; m++) { 
for (i = 0; i < 32; i++) 
buffer[i] = bufout[32+i]; //右半部分32位
//放大变换
worka[ 0] = buffer[31]; 
worka[ 1] = buffer[ 0]; 
worka[ 2] = buffer[ 1]; 
worka[ 3] = buffer[ 2]; 
worka[ 4] = buffer[ 3]; 
worka[ 5] = buffer[ 4]; 
worka[ 6] = buffer[ 3]; 
worka[ 7] = buffer[ 4]; 
worka[ 8] = buffer[ 5]; 
worka[ 9] = buffer[ 6]; 
worka[10] = buffer[ 7]; 
worka[11] = buffer[ 8]; 
worka[12] = buffer[ 7]; 
worka[13] = buffer[ 8]; 
worka[14] = buffer[ 9]; 
worka[15] = buffer[10]; 
worka[16] = buffer[11]; 
worka[17] = buffer[12]; 
worka[18] = buffer[11]; 
worka[19] = buffer[12]; 
worka[20] = buffer[13]; 
worka[21] = buffer[14]; 
worka[22] = buffer[15]; 
worka[23] = buffer[16]; 
worka[24] = buffer[15]; 
worka[25] = buffer[16]; 
worka[26] = buffer[17]; 
worka[27] = buffer[18]; 
worka[28] = buffer[19]; 
worka[29] = buffer[20]; 
worka[30] = buffer[19]; 
worka[31] = buffer[20]; 
worka[32] = buffer[21]; 
worka[33] = buffer[22]; 
worka[34] = buffer[23]; 
worka[35] = buffer[24]; 
worka[36] = buffer[23]; 
worka[37] = buffer[24]; 
worka[38] = buffer[25]; 
worka[39] = buffer[26]; 
worka[40] = buffer[27]; 
worka[41] = buffer[28]; 
worka[42] = buffer[27]; 
worka[43] = buffer[28]; 
worka[44] = buffer[29]; 
worka[45] = buffer[30]; 
worka[46] = buffer[31]; 
worka[47] = buffer[ 0]; 
if (flg) { //加密移位
shift1 = shift[m-1]; //查找每次循环对应的key 循环左移位数
for (i = 0; i< shift1; i++) 
{ //C0 ....循环左移
temp1 = kwork[0]; 
temp2 = kwork[28]; 
for (j = 0; j < 27; j++)
 { 
kwork[j] = kwork[j+1]; 
kwork[j+28] = kwork[j+29]; 
} 
kwork[27] = temp1; 
kwork[55] = temp2; 
} 
} 
if(flg){
//子密钥压缩置换56---48
kn[ 0] = kwork[13]; 
kn[ 1] = kwork[16]; 
kn[ 2] = kwork[10]; 
kn[ 3] = kwork[23]; 
kn[ 4] = kwork[ 0]; 
kn[ 5] = kwork[ 4]; 
kn[ 6] = kwork[ 2]; 
kn[ 7] = kwork[27]; 
kn[ 8] = kwork[14]; 
kn[ 9] = kwork[ 5]; 
kn[10] = kwork[20];