DES和AES加密.docx
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DES和AES加密
DES和AES加密实验日志
实验题目:
DES和AES分组密码
实验目的:
分组密码将明文分成一组一组,在密钥的控制下,经过加密变换生成一组一组的密文。
具体而言,分组密码就是将明文消息序列
划分成等长的消息组
在密钥
的控制下按固定的加密算法一组一组进行加密,输出一组一组密文
。
下面的实验以DES算法为例,DES算法明文分组长为64bit,加密后得到64bit的密文,输入初始种子密钥为64bit,第8、16、24、32、40、48、56、64为奇偶校验位,实际的密钥长为56bit。
DES加密过程由三个阶段来完成:
(1)初始置换IP,用于重排明文分组的64bit数据;
(2)相同结构的16轮迭代,每轮中都有置换和代换运算,第16轮变换的输出分为左右两半,并交换次序。
(3)逆初始置换IP-1(为IP的逆)后,产生64bit的密文。
实验要求:
(1)Windows系列操作系统;
(2)VC6.0编程环境。
(3)提交完整的程序代码清单和详细的注释;
(4)要求有程序运行结果显示。
当加密成功时,得到密文;输入相同的密钥,能将密文恢复成明文。
实验主要步骤:
(1)熟悉分组密码加解密算法的基本原理,加深对所提供的部分源程序的理解;
(2)分析源程序中密码算法的加解密和子密钥生成等典型模块的主要功能,并对源程序加上注释;
(3)在已提供的部分源程序的基础上,添加源程序省缺的部分;
(4)对给定的消息分组进行加解密运算和验证。
实验源代码:
voidEncodeMain();//EncodeMainfunction
voidDecodeMain();//Sorry,ithasnotused
voidDecode(int*str,int*keychar);//decode:
input8chars,8keychars
voidEncode(int*str,int*keychar);//encode:
input8chars,8keychars
voidkeyBuild(int*keychar);//createkeyarray
voidStrtoBin(int*midkey,int*keychar);//changeintobinary
voidkeyCreate(int*midkey2,intmovebit,inti);//callbykeyBuild
voidEncodeData(int*lData,int*rData,int*srt);//encodedatafunction
voidF(int*rData,int*key);//Ffunction
voidExpand(int*rData,int*rDataP);//Expandfunction
voidExchangeS(int*rDataP,int*rData);//S-diagramchange
voidExchangeP(int*rData);//Pchange
voidFillBin(int*rData,intn,ints);//datatobinary;callbyS-Diagramchangefunction
voidDecodeData(int*str,int*lData,int*rData);//DecodeDatafrombinary
intIP1[]={58,50,42,34,26,18,10,2,60,52,44,36,28,20,12,4,//initialchange
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,
};
intIP2[]={40,8,48,16,56,24,64,32,39,7,47,15,55,23,63,31,//oppinitialchange
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
};
ints[][4][16]={{//S-diagramarray
{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}
}
};
intEx[48]={32,1,2,3,4,5,//Expandarray
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
};
intP[32]={16,7,20,21,//P-change
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
};
intPC1[56]={57,49,41,33,25,17,9,//PC-1inkeyBuild
1,58,50,42,34,26,18,
10,2,59,51,43,35,27,
19,11,3,60,52,44,36,
63,55,47,39,31,33,15,
7,62,54,46,38,30,22,
14,6,61,53,45,37,29,
21,13,5,28,20,12,4
};
intPC2[48]={14,17,11,24,1,5,//PC-2inkeyBuild
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
};
再创建des.cpp
内容如下:
#include
#include
#include"des_encode.h"
intkey[16][48];
charstr[8];
voidmain()//mainfunction
{
EncodeMain();
}
voidEncodeMain()//EncodeMainfunction
{
inti;
charkeychar[8];
intkey2[8];
intstrkey[8];
printf("请输入8个要加密的字符:
\n");
for(i=0;i<8;i++)
scanf("%c",&str[i]);
getchar();
for(i=0;i<8;i++)
strkey[i]=str[i];
printf("\n输入明文的十六进制为:
\n");
for(i=0;i<8;i++)
printf("%10x",strkey[i]);
printf("\n请输入密钥(8个字符):
\n");
for(i=0;i<8;i++)
scanf("%c",&keychar[i]);
for(i=0;i<8;i++)
key2[i]=keychar[i];
getchar();
//printf("%c",keychar[i]);
Encode(strkey,key2);
printf("\n加密后十六进制密文是:
\n");
for(i=0;i<8;i++)
printf("%10x",strkey[i]);
printf("\n\n清输入解密密码\n");
for(i=0;i<8;i++)
scanf("%c",&keychar[i]);
for(i=0;i<8;i++)
key2[i]=keychar[i];
Decode(strkey,key2);
for(i=0;i<8;i++)
printf("%10x",strkey[i]);
for(i=0;i<8;i++)
str[i]=strkey[i];
printf("\n明文为:
\t");
for(i=0;i<8;i++)
printf("%c",str[i]);
printf("\n\n");
}
voidkeyBuild(int*keychar){//createkeyarray
inti,j;
intmovebit[]={1,1,2,2,2,2,2,2,
1,2,2,2,2,2,2,1};
intmidkey2[56];
intmidkey[64];
StrtoBin(midkey,keychar);
for(i=0;i<56;i++)
midkey2[i]=midkey[PC1[i]-1];
for(i=0;i<16;i++)
keyCreate(midkey2,movebit[i],i);
}
voidStrtoBin(int*midkey,int*keychar){//changeintobinary
inttrans[8],i,j,k,n;
n=0;
for(i=0;i<8;i++){
j=0;
while(keychar[i]!
=0){
trans[j]=keychar[i]%2;
keychar[i]=keychar[i]/2;
j++;
}
for(k=j;k<8;k++)trans[k]=0;
for(k=0;k<8;k++)
midkey[n++]=trans[7-k];
}
}
voidkeyCreate(int*midkey2,intmovebit,intn){
inti,temp[4];
temp[0]=midkey2[0];
temp[1]=midkey2[1];
temp[2]=midkey2[28];
temp[3]=midkey2[29];
if(movebit==2){
for(i=0;i<26;i++){
midkey2[i]=midkey2[i+2];
midkey2[i+28]=midkey2[i+30];
}
midkey2[26]=temp[0];midkey2[27]=temp[1];
midkey2[54]=temp[2];midkey2[55]=temp[3];}
else
{for(i=0;i<27;i++){
midkey2[i]=midkey2[i+1];
midkey2[i+28]=midkey2[i+29];
}
midkey2[27]=temp[0];midkey2[55]=temp[2];
}
for(i=0;i<48;i++)
key[n][i]=midkey2[PC2[i]-1];
}
voidEncodeData(int*lData,int*rData,int*str){//encodedatafunction
inti,j,temp[8],lint,rint;//inth;
intdata[64];
lint=0,rint=0;
for(i=0;i<4;i++){
j=0;
while(str[i]!
=0){
temp[j]=str[i]%2;
str[i]=str[i]/2;
j++;
}
while(j<8)temp[j++]=0;
for(j=0;j<8;j++)
lData[lint++]=temp[7-j];
j=0;
while(str[i+4]!
=0){
temp[j]=str[i+4]%2;
str[i+4]=str[i+4]/2;
j++;
}
while(j<8)temp[j++]=0;
for(j=0;j<8;j++)rData[rint++]=temp[7-j];
}
for(i=0;i<32;i++){
data[i]=lData[i];
data[i+32]=rData[i];
}
for(i=0;i<32;i++){
lData[i]=data[IP1[i]-1];//printf("P1:
%5d:
%5d,%5d\n",IP1[i],lData[i],data[IP1[i]-1]);
rData[i]=data[IP1[i+32]-1];
}
}
voidF(int*rData,int*key){//Ffunction
inti,rDataP[48];
Expand(rData,rDataP);
for(i=0;i<48;i++){
rDataP[i]=rDataP[i]^key[i];//printf("%10d",rDataP[i]);if((i+1)%6==0)printf("\n");
}
ExchangeS(rDataP,rData);
ExchangeP(rData);
}
voidExpand(int*rData,int*rDataP){//Expandfunction
inti;
for(i=0;i<48;i++)
rDataP[i]=rData[Ex[i]-1];
}
voidExchangeS(int*rDataP,int*rData){//S-diagramchange
inti,n,linex,liney;
linex=liney=0;
for(i=0;i<48;i+=6){
n=i/6;//printf("%10d\n",(rDataP[i]<<1));
linex=(rDataP[i]<<1)+rDataP[i+5];
liney=(rDataP[i+1]<<3)+(rDataP[i+2]<<2)+(rDataP[i+3]<<1)+rDataP[i+4];
FillBin(rData,n,s[n][linex][liney]);
}
}
voidExchangeP(int*rData){//Pchange
inti,temp[32];
for(i=0;i<32;i++)
temp[i]=rData[i];
for(i=0;i<32;i++)
rData[i]=temp[P[i]-1];
}
voidFillBin(int*rData,intn,ints){//datatobinary;callbyS-Diagramchangefunction
inttemp[4],i;
for(i=0;i<4;i++){
temp[i]=s%2;
s=s/2;
}
for(i=0;i<4;i++)
rData[n*4+i]=temp[3-i];
}
voidDecodeData(int*str,int*lData,int*rData){//DecodeDatafrombinary
inti;inta,b;intdata[64];
a=0,b=0;
for(i=0;i<32;i++){
data[i]=lData[i];
data[i+32]=rData[i];
}
for(i=0;i<32;i++){
lData[i]=data[IP2[i]-1];
rData[i]=data[IP2[i+32]-1];
}
for(i=0;i<32;i++){
a=(lData[i]&0x1)+(a<<1);
b=(rData[i]&0x1)+(b<<1);
if((i+1)%8==0){
str[i/8]=a;a=0;//printf("%d",i/8);
str[i/8+4]=b;b=0;//printf("%d",i/8+4);
}
}
}
voidEncode(int*str,int*keychar){//encode:
input8chars,8keychars
intlData[32],rData[32],temp[32],rDataP[48];
inti,j;
keyBuild(keychar);
EncodeData(lData,rData,str);
for(i=0;i<16;i++){
for(j=0;j<32;j++)
temp[j]=rData[j];
F(rData,key[i]);
for(j=0;j<32;j++){
rData[j]=rData[j]^lData[j];
}
for(j=0;j<32;j++)
lData[j]=temp[j];
}
DecodeData(str,rData,lData);
}
voidDecode(int*str,int*keychar){//decode:
input8chars,8keychars
intlData[32],rData[32],temp[32],rDataP[48];
inti,j;
keyBuild(keychar);
EncodeData(lData,rData,str);//这个位置
for(i=0;i<16;i++){
for(j=0;j<32;j++)
temp[j]=rData[j];
F(rData,key[15-i]);
for(j=0;j<32;j++){
rData[j]=rData[j]^lData[j];
}
for(j=0;j<32;j++){
lData[j]=temp[j];
}
}
DecodeData(str,rData,lData);
}
实验结果:
心得体会:
通过本次实验,对DES和AES的应用有了更为直观的了解,在阅读代码过程中,对DES和AES的具体加密解密过程有了更加详细的了解,为以后更好的应用DES和AES加密提供了很好的基础。