/*
create by fanchenyang at 2021
*/
#include<stdio.h>
#include<math.h>
#include<stdlib.h>
/*
初始置换与终止置换
置换的type决定使用的置换方式
type -> 0 初始置换
type -> 1 终止置换
将原始64位数据进行排列
*/
void pBoxChange(int * node,int type,int *resu){
int boxInit[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};
int boxEnd [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};
int var;
int * box;
if(type == 0){
box = boxInit;
}else if(type == 1){
box = boxEnd;
}else{
printf("传入类型有误，请重\n");
return;
}
for(int i = 0; i < 64; i++){
*(resu + i) = node[*(box + i) - 1];
}
}
// p盒置换
void pBoxCh(int * node,int * res){
int box[] = {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
};
for(int i = 0; i < 32; i++){
*(res + i) = node[*(box + i) - 1];
}
}
// 位选择函数
// pri 32
// tar 48
// 将32位明文扩展为48位
void fun_e(int * pri,int * tar){
int box_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
};
for(int i = 0 ; i < 48 ; i++){
*(tar + i) = *(pri + *(box_e + i) - 1);
}
}
/*
S盒压缩
将48位压缩为32位
*/
void SBoxChange(int *right,int * res){
int box [8][64] = {
{
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
}
};
int vv = 0;
for(int i = 0 ; i < 8; i++){
// 拿到行列值
int hang = *(right + i * 6 + 0) * 2 + *(right + i * 6 + 5);
int lie = 0;
for(int j = 4 ; j > 0 ; j--){
lie += *(right + i * 6 + j) * pow(2,4-j);
}
int var[4] = {0,0,0,0};
// printf("行 %d列%d 值\n",hang,lie);
int value = *(*(box + i) + (hang* 16) + lie);
// printf("value=%d",value);
// 将value分解为二进制
for(int j = 0 ; j < 4 ; j++){
var[3 - j] = value % 2;
value /= 2;
}
for(int j = 0 ; j < 4 ; j++)
*(res + vv++) = var[j];
}
}
void getMiYao(int key[64],int keyi[][48]){
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
};
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
};
int pp [56] ;
for(int i = 0 ; i < 56 ; i++){
*(pp + i) = key[*(pc_1 + i) - 1];
}
for(int i = 0 ; i < 16 ; i++){
if(i == 0 ||i == 1|| i == 8||i == 15){
// 循环左移一位
int var = *(pp);
for(int j = 1 ; j < 28 ; j++){
*(pp + j - 1) =*(pp + j);
}
*(pp + 27) = var;
var = *(pp + 28);
for(int j = 29 ; j < 56 ; j++){
*(pp + j -1) = *(pp + j);
}
*(pp + 55) = var;
}else{
//循环左移两位
int var1 = *(pp);
int var2 = *(pp+1);
for(int j = 2 ; j < 28 ; j++){
*(pp + j - 1) =*(pp + j);
}
*(pp + 26) = var1;
*(pp + 27) = var2;
var1 = *(pp + 28);
var2 = *(pp + 29);
for(int j = 30 ; j < 56 ; j++){
*(pp + j -1) = *(pp + j);
}
*(pp + 54) = var1;
*(pp + 55) = var2;
}
for(int j = 0 ; j < 48 ; j++){
*(keyi[i]+j) = *(pp + (*(pc_2 + j) - 1));
}
}
}
// primary 明文 加密后的结果仍放其中
void DESEncode(int * primary,int miyao[][48]){
// 将明文经过p盒置换的结果放在result中
int result [64] = {};
pBoxChange(primary,0,result);
for(int i = 0 ; i < 16 ; i++){
int asd[48];
// 对r0做备份
int ee[32];
for(int j = 0 ; j < 32 ;j++){
ee[j] = *(result + j + 32);
}
// 存放48位扩展明文
int e[48];
//扩展明文
fun_e(result + 32,e);
// printf("扩展明文完成\n");
// 存放32位Sbox转换后的数据
int ss[32];
for(int j = 0 ; j < 48 ; j++){
*(asd + j) = *(e + j) ^ *(*(miyao + i) + j);
// printf("%d",*(asd + j));
}
// printf("sbox开始\n");
SBoxChange(asd,ss);
// printf("sbox完成\n");
int p_result[32];
pBoxCh(ss,p_result);
// printf("\n");
// for(int i = 0 ; i < 32 ; i++){
// if(i % 6 == 0)
// printf("\n");
//
// printf("%d ",ss[i]);
// }
// printf("===\n");
//
//
for(int j = 0 ; j < 32 ; j++){
result[32 + j] = result[j] ^ p_result[j];// r1 = l0 ^ p_result
result[j] = ee[j]; // l1 = r0
}
// for(int i = 0 ; i < 64 ; i++){
//
// if(i % 8 == 0)
// printf("\n");
//
// printf("%d ",result[i]);
//
// }
// printf("\n");
}
//逆置换
pBoxChange(result,1,primary);
}
// DES解密
void Decode(int * primary,int miyao[][48]){
// 将明文经过p盒置换的结果放在result中
int result [64] = {};
pBoxChange(primary,0,result);
for(int i = 0 ; i < 16 ; i++){
int asd[48];
// 对l0做备份
int ee[32];
for(int j = 0 ; j < 32 ;j++){
ee[j] = *(result + j);
}
// 存放48位扩展明文
int e[48];
//扩展明文
fun_e(result,e);
// printf("扩展明文完成 %d\n",i);
// 存放32位Sbox转换后的数据
int ss[32];
for(int j = 0 ; j < 48 ; j++){
*(asd + j) = *(e + j) ^ *(*(miyao + 15 - i) + j);
}
// printf("sbox开始\n");
SBoxChange(asd,ss);
// printf("sbox完成\n");
int p_result[32];
pBoxCh(ss,p_result);
// printf("\n");
// for(int i = 0 ; i < 32 ; i++){
// if(i % 6 == 0)
// printf("\n");
//
// printf("%d ",ss[i]);
// }
// printf("===\n");
for(int j = 0 ; j < 32 ; j++){
result[j] = result[j + 32] ^ p_result[j];// r1 = l0 ^ p_result
result[j + 32] = ee[j]; // l1 = r0
}
}
//逆置换
pBoxChange(result,1,primary);
}
// 测试
//void test(){
// int key[64] = {0};
// int x[64] = {0};
// printf("\n\n");
// DESEncode(x,key);
// for(int i = 0 ; i < 64 ; i++){
// if(i % 8 == 0){
// printf("\n");
// }
// printf("%d",*(x+i));
// }
// Decode(x,key);
// for(int i = 0 ; i < 64 ; i++){
// if(i % 8 == 0){
// printf("\n");
// }
// printf("%d",*(x+i));
// }
//}
// 将字符串转化为二进制数组
void changeStringToarray(char * s,int * array){
// for(int i = 0 ; i < size i ++){
// 每8个字符封装为一个64位二进制字符串，剩余的补零
// }
for(int i = 0 ; i < 8 ; i++){
for(int j = 0 ; j < 8 ;j ++){
*(array + 8 * i + j) = (*(s+i) >> (7 - j)) & 1;
}
}
}
void changeArrayToString(int * array,char * s){
for(int i = 0 ; i < 8 ; i++)
*(s + i) = 0;
for(int i = 0 ; i < 64 ; i++){
*(s + i / 8) += *(array + i) * pow(2,7 - i % 8);
}
// printf("\n");
// for(int i = 0 ; i < 8 ; i++)
// printf("%c\n",*(s+i));
}
// 输入 密文 输入 秘钥
void input(){
printf("加密请输入E解密输入D\n");
char pp;
int type;
scanf("%c",&pp);
char s[100] = {'\0'};
char d[100] = {'\0'};
if(pp == 'D' || pp == 'd'){
type = 1;
printf("请输入要解密的文件路径\n");
scanf("%s",s);
printf("加密后文件存放路径\n");
scanf("%s",d);
}
else if(pp == 'E' || pp == 'e'){
type = 0;
printf("请输入要加密的文件路径\n");
scanf("%s",s);
printf("加密后文件存放路径\n");
scanf("%s",d);
}
else {
printf("输入异常\n");
return ;
}
char key[8];
printf("请先输入 8 位 字符 秘钥 \n");
for(int i = 0 ; i < 8 ; i++){
scanf("%c",key + i);
}
int keybit [64];
changeStringToarray(key,keybit);
// //初始化16轮迭代密钥
int miyao [16][48] = {{0}};
getMiYao(keybit,miyao);
char miwen[9] = {'\0'};
//读取明文文件 每8位 分为一组
FILE * fs;
// fs = fopen("D:\\DES\\明文.txt","r");
fs = fopen(s,"r");
FILE * fo = fopen(d,"w");
// 读取8位
char c;
int curIndex = 0;
char container [8];
if(fs == NULL)
printf("asda\n");
while((c = fgetc(fs)) != EOF){
// printf("%d\n",curIndex);
container[curIndex] = c;
if(curIndex == 7){
// size等于8说明集齐一组 数据
// 调用函数 得到加密 密文
// TODO 将密文 写在 输出流中
int a[64];
changeStringToarray(container,a);
if(type == 0)
DESEncode(a,miyao);
else
Decode(a,miyao);
changeArrayToString(a,miwen);
fputs(miwen,fo);
// printf("asdasd\n");
}
curIndex = (++curIndex) % 8;
}
// 如果剩余数据凑不够8个字符即64位二进制，默认按照高位补 “空格 ”
// 如果 curIndex == 0 说明 每组8位刚刚好 直接return
if(curIndex != 0){
// 补位并计算
for(int i = curIndex; i < 8 ; i++){
container[i] = ' ';
}
//TODO 调用函数 转为 密文 并写到输出流
int a[64];
changeStringToarray(container,a);
if(type == 0)
DESEncode(a,miyao);
else
Decode(a,miyao);
changeArrayToString(a,miwen);
fputs(miwen,fo);
}
fclose(fo);
fclose(fs);
}
int main(){
input();
return 0;
}
