des加密算法如下:
一、DES加密算法简介
DES(Data Encryption Standard)是目前最为流行的加密算法之一。DES是对称的,也就是说它使用同一个密钥来加密和解密数据。
DES还是一种分组加密算法,该算法每次处理固定长度的数据段,称之为分组。DES分组的大小是64位,如果加密的数据长度不是64位的倍数,可以按照某种具体的规则来填充位。
从本质上来说,DES的安全性依赖于虚假表象,从密码学的术语来讲就是依赖于“混乱和扩散”的原则。混乱的目的是为隐藏任何明文同密文、或者密钥之间的关系,而扩散的目的是使明文中的有效位和密钥一起组成尽可能多的密文。两者结合到一起就使得安全性变得相对较高。
DES算法具体通过对明文进行一系列的排列和替换操作来将其加密。过程的关键就是从给定的初始密钥中得到16个子密钥的函数。要加密一组明文,每个子密钥按照顺序(1-16)以一系列的位操作施加于数据上,每个子密钥一次,一共重复16次。每一次迭代称之为一轮。要对密文进行解密可以采用同样的步骤,只是子密钥是按照逆向的顺序(16-1)对密文进行处理。
❷ 关于vc的des加密问题
DES算法处理的数据对象是一组64比特的明文串.设该明文串为m=m1m2…m64 (mi=0或1).明文串经过64比特的密钥K来加密,最后生成长度为64比特的密文E.其加密过程图示如下:
DES算法加密过程
对DES算法加密过程图示的说明如下:待加密的64比特明文串m,经过IP置换后,得到的比特串的下
标列表如下:
IP585042342618102
605244362820124
625446383022146
645648403224168
57494133251791
595143352719113
61534537295
635547393123157
❸ 使用C/C++语言,将DES/AES加密算法,用代码实现
哎,学校大作业吧。核心是des和aes的算法呗,自己一点点写代码量不很少呢。没时间给你写了。
不过有个很好的偷懒办法:建议lz你去找一下OpenSSL的源码。里面有AES,DES的原生C实现。现成函数。lz你直接从里面抠出来复制到你工程里就行了。。
❹ des加密算法(c/c++)
des.h文件:
#ifndefCRYPTOPP_DES_H
#defineCRYPTOPP_DES_H
#include"cryptlib.h"
#include"misc.h"
NAMESPACE_BEGIN(CryptoPP)
classDES:publicBlockTransformation
{
public:
DES(constbyte*userKey,CipherDir);
voidProcessBlock(constbyte*inBlock,byte*outBlock)const;
voidProcessBlock(byte*inoutBlock)const
{DES::ProcessBlock(inoutBlock,inoutBlock);}
enum{KEYLENGTH=8,BLOCKSIZE=8};
unsignedintBlockSize()const{returnBLOCKSIZE;}
protected:
staticconstword32Spbox[8][64];
SecBlock<word32>k;
};
classDESEncryption:publicDES
{
public:
DESEncryption(constbyte*userKey)
:DES(userKey,ENCRYPTION){}
};
classDESDecryption:publicDES
{
public:
DESDecryption(constbyte*userKey)
:DES(userKey,DECRYPTION){}
};
classDES_EDE_Encryption:publicBlockTransformation
{
public:
DES_EDE_Encryption(constbyte*userKey)
:e(userKey,ENCRYPTION),d(userKey+DES::KEYLENGTH,DECRYPTION){}
voidProcessBlock(constbyte*inBlock,byte*outBlock)const;
voidProcessBlock(byte*inoutBlock)const;
enum{KEYLENGTH=16,BLOCKSIZE=8};
unsignedintBlockSize()const{returnBLOCKSIZE;}
private:
DESe,d;
};
classDES_EDE_Decryption:publicBlockTransformation
{
public:
DES_EDE_Decryption(constbyte*userKey)
:d(userKey,DECRYPTION),e(userKey+DES::KEYLENGTH,ENCRYPTION){}
voidProcessBlock(constbyte*inBlock,byte*outBlock)const;
voidProcessBlock(byte*inoutBlock)const;
enum{KEYLENGTH=16,BLOCKSIZE=8};
unsignedintBlockSize()const{returnBLOCKSIZE;}
private:
DESd,e;
};
classTripleDES_Encryption:publicBlockTransformation
{
public:
TripleDES_Encryption(constbyte*userKey)
:e1(userKey,ENCRYPTION),d(userKey+DES::KEYLENGTH,DECRYPTION),
e2(userKey+2*DES::KEYLENGTH,ENCRYPTION){}
voidProcessBlock(constbyte*inBlock,byte*outBlock)const;
voidProcessBlock(byte*inoutBlock)const;
enum{KEYLENGTH=24,BLOCKSIZE=8};
unsignedintBlockSize()const{returnBLOCKSIZE;}
private:
DESe1,d,e2;
};
classTripleDES_Decryption:publicBlockTransformation
{
public:
TripleDES_Decryption(constbyte*userKey)
:d1(userKey+2*DES::KEYLENGTH,DECRYPTION),e(userKey+DES::KEYLENGTH,ENCRYPTION),
d2(userKey,DECRYPTION){}
voidProcessBlock(constbyte*inBlock,byte*outBlock)const;
voidProcessBlock(byte*inoutBlock)const;
enum{KEYLENGTH=24,BLOCKSIZE=8};
unsignedintBlockSize()const{returnBLOCKSIZE;}
private:
DESd1,e,d2;
};
NAMESPACE_END
#endif
des.cpp文件:
//des.cpp-modifiedbyWeiDaifrom:
/*
*
*circa1987,'s1977
*publicdomaincode.,but
*theactualencrypt/
*Outerbridge'sDEScodeasprintedinSchneier's"AppliedCryptography."
*
*Thiscodeisinthepublicdomain.Iwouldappreciatebugreportsand
*enhancements.
*
*PhilKarnKA9Q,[email protected],August1994.
*/
#include"pch.h"
#include"misc.h"
#include"des.h"
NAMESPACE_BEGIN(CryptoPP)
/*
*Threeofthesetables,theinitialpermutation,thefinal
*,areregularenoughthat
*forspeed,wehard-codethem.They'rehereforreferenceonly.
*Also,,gensp.c,
*tobuildthecombinedSPbox,Spbox[].They'realsoherejust
*forreference.
*/
#ifdefnotdef
/*initialpermutationIP*/
staticbyteip[]={
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
};
/*finalpermutationIP^-1*/
staticbytefp[]={
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
};
/*expansionoperationmatrix*/
staticbyteei[]={
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
};
/*The(in)famousS-boxes*/
staticbytesbox[8][64]={
/*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
};
/*32--boxes*/
staticbytep32i[]={
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
};
#endif
/*permutedchoicetable(key)*/
staticconstbytepc1[]={
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
};
/*numberleftrotationsofpc1*/
staticconstbytetotrot[]={
1,2,4,6,8,10,12,14,15,17,19,21,23,25,27,28
};
/*permutedchoicekey(table)*/
staticconstbytepc2[]={
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
};
/*EndofDES-definedtables*/
/*bit0isleft-mostinbyte*/
staticconstintbytebit[]={
0200,0100,040,020,010,04,02,01
};
/*Setkey(initializekeyschelearray)*/
DES::DES(constbyte*key,CipherDirdir)
:k(32)
{
SecByteBlockbuffer(56+56+8);
byte*constpc1m=buffer;/*placetomodifypc1into*/
byte*constpcr=pc1m+56;/*placetorotatepc1into*/
byte*constks=pcr+56;
registerinti,j,l;
intm;
for(j=0;j<56;j++){/*convertpc1tobitsofkey*/
l=pc1[j]-1;/*integerbitlocation*/
m=l&07;/*findbit*/
pc1m[j]=(key[l>>3]&/*findwhichkeybytelisin*/
bytebit[m])/*andwhichbitofthatbyte*/
?1:0;/*andstore1-bitresult*/
}
for(i=0;i<16;i++){/*keychunkforeachiteration*/
memset(ks,0,8);/*Clearkeyschele*/
for(j=0;j<56;j++)/*rotatepc1therightamount*/
pcr[j]=pc1m[(l=j+totrot[i])<(j<28?28:56)?l:l-28];
/**/
for(j=0;j<48;j++){/*selectbitsindivially*/
/*checkbitthatgoestoks[j]*/
if(pcr[pc2[j]-1]){
/*maskitinifit'sthere*/
l=j%6;
ks[j/6]|=bytebit[l]>>2;
}
}
/*Nowconverttoodd/eveninterleavedformforuseinF*/
k[2*i]=((word32)ks[0]<<24)
|((word32)ks[2]<<16)
|((word32)ks[4]<<8)
|((word32)ks[6]);
k[2*i+1]=((word32)ks[1]<<24)
|((word32)ks[3]<<16)
|((word32)ks[5]<<8)
|((word32)ks[7]);
}
if(dir==DECRYPTION)//reversekeyscheleorder
for(i=0;i<16;i+=2)
{
std::swap(k[i],k[32-2-i]);
std::swap(k[i+1],k[32-1-i]);
}
}
/**/
/*Ccodeonlyinportableversion*/
//RichardOuterbridge'sinitialpermutationalgorithm
/*
inlinevoidIPERM(word32&left,word32&right)
{
word32work;
work=((left>>4)^right)&0x0f0f0f0f;
right^=work;
left^=work<<4;
work=((left>>16)^right)&0xffff;
right^=work;
left^=work<<16;
work=((right>>2)^left)&0x33333333;
left^=work;
right^=(work<<2);
work=((right>>8)^left)&0xff00ff;
left^=work;
right^=(work<<8);
right=rotl(right,1);
work=(left^right)&0xaaaaaaaa;
left^=work;
right^=work;
left=rotl(left,1);
}
inlinevoidFPERM(word32&left,word32&right)
{
word32work;
right=rotr(right,1);
work=(left^right)&0xaaaaaaaa;
left^=work;
right^=work;
left=rotr(left,1);
work=((left>>8)^right)&0xff00ff;
right^=work;
left^=work<<8;
work=((left>>2)^right)&0x33333333;
right^=work;
left^=work<<2;
work=((right>>16)^left)&0xffff;
left^=work;
right^=work<<16;
work=((right>>4)^left)&0x0f0f0f0f;
left^=work;
right^=work<<4;
}
*/
//WeiDai''sinitialpermutation
//algorithm,
//(likeinMSVC)
inlinevoidIPERM(word32&left,word32&right)
{
word32work;
right=rotl(right,4U);
work=(left^right)&0xf0f0f0f0;
left^=work;
right=rotr(right^work,20U);
work=(left^right)&0xffff0000;
left^=work;
right=rotr(right^work,18U);
work=(left^right)&0x33333333;
left^=work;
right=rotr(right^work,6U);
work=(left^right)&0x00ff00ff;
left^=work;
right=rotl(right^work,9U);
work=(left^right)&0xaaaaaaaa;
left=rotl(left^work,1U);
right^=work;
}
inlinevoidFPERM(word32&left,word32&right)
{
word32work;
right=rotr(right,1U);
work=(left^right)&0xaaaaaaaa;
right^=work;
left=rotr(left^work,9U);
work=(left^right)&0x00ff00ff;
right^=work;
left=rotl(left^work,6U);
work=(left^right)&0x33333333;
right^=work;
left=rotl(left^work,18U);
work=(left^right)&0xffff0000;
right^=work;
left=rotl(left^work,20U);
work=(left^right)&0xf0f0f0f0;
right^=work;
left=rotr(left^work,4U);
}
//
voidDES::ProcessBlock(constbyte*inBlock,byte*outBlock)const
{
word32l,r,work;
#ifdefIS_LITTLE_ENDIAN
l=byteReverse(*(word32*)inBlock);
r=byteReverse(*(word32*)(inBlock+4));
#else
l=*(word32*)inBlock;
r=*(word32*)(inBlock+4);
#endif
IPERM(l,r);
constword32*kptr=k;
for(unsignedi=0;i<8;i++)
{
work=rotr(r,4U)^kptr[4*i+0];
l^=Spbox[6][(work)&0x3f]
^Spbox[4][(work>>8)&0x3f]
^Spbox[2][(work>>16)&0x3f]
^Spbox[0][(work>>24)&0x3f];
work=r^kptr[4*i+1];
l^=Spbox[7][(work)&0x3f]
^Spbox[5][(work>>8)&0x3f]
^Spbox[3][(work>>16)&0x3f]
^Spbox[1][(work>>24)&0x3f];
work=rotr(l,4U)^kptr[4*i+2];
r^=Spbox[6][(work)&0x3f]
^Spbox[4][(work>>8)&0x3f]
^Spbox[2][(work>>16)&0x3f]
^Spbox[0][(work>>24)&0x3f];
work=l^kptr[4*i+3];
r^=Spbox[7][(work)&0x3f]
^Spbox[5][(work>>8)&0x3f]
^Spbox[3][(work>>16)&0x3f]
^Spbox[1][(work>>24)&0x3f];
}
FPERM(l,r);
#ifdefIS_LITTLE_ENDIAN
*(word32*)outBlock=byteReverse(r);
*(word32*)(outBlock+4)=byteReverse(l);
#else
*(word32*)outBlock=r;
*(word32*)(outBlock+4)=l;
#endif
}
voidDES_EDE_Encryption::ProcessBlock(byte*inoutBlock)const
{
e.ProcessBlock(inoutBlock);
d.ProcessBlock(inoutBlock);
e.ProcessBlock(inoutBlock);
}
voidDES_EDE_Encryption::ProcessBlock(constbyte*inBlock,byte*outBlock)const
{
e.ProcessBlock(inBlock,outBlock);
d.ProcessBlock(outBlock);
e.ProcessBlock(outBlock);
}
voidDES_EDE_Decryption::ProcessBlock(byte*inoutBlock)const
{
d.ProcessBlock(inoutBlock);
e.ProcessBlock(inoutBlock);
d.ProcessBlock(inoutBlock);
}
voidDES_EDE_Decryption::ProcessBlock(constbyte*inBlock,byte*outBlock)const
{
d.ProcessBlock(inBlock,outBlock);
e.ProcessBlock(outBlock);
d.ProcessBlock(outBlock);
}
voidTripleDES_Encryption::ProcessBlock(byte*inoutBlock)const
{
e1.ProcessBlock(inoutBlock);
d.ProcessBlock(inoutBlock);
e2.ProcessBlock(inoutBlock);
}
voidTripleDES_Encryption::ProcessBlock(constbyte*inBlock,byte*outBlock)const
{
e1.ProcessBlock(inBlock,outBlock);
d.ProcessBlock(outBlock);
e2.ProcessBlock(outBlock);
}
voidTripleDES_Decryption::ProcessBlock(byte*inoutBlock)const
{
d1.ProcessBlock(inoutBlock);
e.ProcessBlock(inoutBlock);
d2.ProcessBlock(inoutBlock);
}
voidTripleDES_Decryption::ProcessBlock(constbyte*inBlock,byte*outBlock)const
{
d1.ProcessBlock(inBlock,outBlock);
e.ProcessBlock(outBlock);
d2.ProcessBlock(outBlock);
}
NAMESPACE_END
程序运行如下:
❺ des是什么算法
DES算法为密码体制中的对称密码体制。
DES算法为密码体制中的对称密码体制,又被称为美国数据加密标准,是1972年美国IBM公司研制的对称密码体制加密算法。明文按64位进行分组,密钥长64位,密钥事实上是56位参与DES运算,分组后的明文组和56位的密钥按位替代或交换的方法形成密文组的加密方法。
des的应用领域
计算机网络通信:对计算机网络通信中的数据提供保护是DES的一项重要应用。但这些被保护的数据一般只限于民用敏感信息,即不在政府确定的保密范围之内的信息。
电子资金传送系统:采用DES的方法加密电子资金传送系统中的信息,可准确、快速地传送数据,并可较好地解决信息安全的问题。
保护用户文件:用户可自选密钥对重要文件加密,防止未授权用户窃密。
用户识别:DES还可用于计算机用户识别系统中。
❻ 用C++或者C语言实现DES算法,明文learing,密钥computer.求出密文(写出过程)
#include
DWORDLONG dwlKey_PC_1[64]={
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,
21,13,5,28,20,12,4,0};
DWORDLONG dwlKey_PC_2[64]={
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,
46,42,50,36,29,32,0};
DWORDLONG dwlData_IP[65]={
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,
63,55,47,39,31,23,15,7,0};
DWORDLONG dwlData_Expansion[64]={
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,
28,29,30,31,32,1,0};
DWORDLONG dwlData_P[33]={
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,
22,11,4,25,0};
DWORDLONG dwlData_FP[65]={
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,
33,1,41,9,49,17,57,25,0};
DWORDLONG OS[512]={
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
};
-------------------------------------
des.cpp
-------------------------------------
/*注意:这只是标准DES算法的例子,所以速度并不是很快,不适用于大量数据加密的场*/
/*合.UNIX的密码也采用DES,不过它在里面加了点其它的东西.所以结果和DES的结果 */
/*不一样. 由于使用了WINDOWS类库,所以必须在WINDOWS环境下编译. */
/**************************************************************************/
#include
#include
#include
#include
#include "Schedle.h"
class CShift{
public:
DWORDLONG mask[16];
int step[16];
CShift(){
for(int i=0;i step=2;
mask=0xc000000;
}
step[0]=step[1]=step[8]=step[15]=1;
mask[0]=mask[1]=mask[8]=mask[15]=0x8000000;
}
};
class CDES{
public:
CDES(){
m_dwlKey=0;
m_dwlData=0;
ConvertTableToMask(dwlKey_PC_1,64);
//PrintTable(dwlKey_PC_1,7,8);
ConvertTableToMask(dwlKey_PC_2,56);
ConvertTableToMask(dwlData_IP,64);
ConvertTableToMask(dwlData_Expansion,32);
ConvertTableToMask(dwlData_FP,64);
ConvertTableToMask(dwlData_P,32);
Generate_S();
}
void PrintBit(DWORDLONG);
void EncryptKey(char *);
unsigned char* EncryptData(unsigned char *);
unsigned char* DescryptData(unsigned char*);
private:
void ConvertTableToMask(DWORDLONG *,int);
void Generate_S(void);
void PrintTable(DWORDLONG*,int,int);
DWORDLONG ProcessByte(unsigned char*,BOOL);
DWORDLONG PermuteTable(DWORDLONG,DWORDLONG*,int);
void Generate_K(void);
void EncryptKernel(void);
DWORDLONG Generate_B(DWORDLONG,DWORDLONG*);
/*For verify schele permutation only*/
DWORDLONG UnPermuteTable(DWORDLONG,DWORDLONG*,int);
/**************************************/
DWORDLONG dwlData_S[9][4][16];
CShift m_shift;
DWORDLONG m_dwlKey;
DWORDLONG m_dwlData;
DWORDLONG m_dwl_K[17];
};
void CDES::EncryptKey(char *key){
printf("\nOriginal Key: %s",key);
m_dwlKey=ProcessByte((unsigned char*)key,TRUE);
//PrintBit(m_dwlKey);
m_dwlKey=PermuteTable(m_dwlKey,dwlKey_PC_1,56);
//PrintBit(m_dwlKey);
Generate_K();
//printf("\n******************************************\n");
}
void CDES::Generate_K(void){
DWORDLONG C[17],D[17],tmp;
C[0]=m_dwlKey>>28;
D[0]=m_dwlKey&0xfffffff;
for(int i=1;i tmp=(C[i-1]&m_shift.mask[i-1])>>(28-m_shift.step[i-1]);
C=((C[i-1] tmp=(D[i-1]&m_shift.mask[i-1])>>(28-m_shift.step[i-1]);
D=((D[i-1] m_dwl_K=(C m_dwl_K=PermuteTable(m_dwl_K,dwlKey_PC_2,48);
}
}
DWORDLONG CDES::ProcessByte(unsigned char *key,BOOL shift){
unsigned char tmp;
DWORDLONG byte=0;
int i=0;
while(i while(*key){
if(byte!=0)
byte tmp=*key;
if(shift)
tmp byte│=tmp;
i++;
key++;
}
if(i byte i++;
}
return byte;
}
DWORDLONG CDES::PermuteTable(DWORDLONG dwlPara,DWORDLONG* dwlTable,int nDestLen)
{
int i=0;
DWORDLONG tmp=0,moveBit;
while(i moveBit=1;
if(dwlTable&dwlPara){
moveBit tmp│=moveBit;
}
i++;
}
return tmp;
}
DWORDLONG CDES::UnPermuteTable(DWORDLONG dwlPara,DWORDLONG* dwlTable,int nDestLe
n){
DWORDLONG tmp=0;
int i=nDestLen-1;
while(dwlPara!=0){
if(dwlPara&0x01)
tmp│=dwlTable;
dwlPara>>=1;
i--;
}
return tmp;
}
void CDES::PrintTable(DWORDLONG *dwlPara,int col,int row){
int i,j;
for(i=0;i printf("\n");
getch();
for(j=0;j PrintBit(dwlPara[i*col+j]);
}
}
void CDES::PrintBit(DWORDLONG bitstream){
char out[76];
int i=0,j=0,space=0;
while(bitstream!=0){
if(bitstream&0x01)
out[i++]='1';
else
out[i++]='0';
j++;
if(j%8==0){
out[i++]=' ';
space++;
}
bitstream=bitstream>>1;
}
out='\0';
strcpy(out,strrev(out));
printf("%s **:%d\n",out,i-space);
}
void CDES::ConvertTableToMask(DWORDLONG *mask,int max){
int i=0;
DWORDLONG nBit=1;
while(mask!=0){
nBit=1;
nBit mask[i++]=nBit;
}
}
void CDES::Generate_S(void){
int i;
int j,m,n;
m=n=0;
j=1;
for(i=0;i dwlData_S[j][m][n]=OS;
n=(n+1)%16;
if(!n){
m=(m+1)%4;
if(!m)
j++;
}
}
}
unsigned char * CDES::EncryptData(unsigned char *block){
unsigned char *EncrytedData=new unsigned char(15);
printf("\nOriginal Data: %s\n",block);
m_dwlData=ProcessByte(block,0);
//PrintBit(m_dwlData);
m_dwlData=PermuteTable(m_dwlData,dwlData_IP,64);
EncryptKernel();
//PrintBit(m_dwlData);
DWORDLONG bit6=m_dwlData;
for(int i=0;i EncrytedData[7-i]=(unsigned char)(bit6&0x3f)+46;
bit6>>=6;
}
EncrytedData[11]='\0';
printf("\nAfter Encrypted: %s",EncrytedData);
for(i=0;i EncrytedData[7-i]=(unsigned char)(m_dwlData&0xff);
m_dwlData>>=8;
}
EncrytedData[8]='\0';
return EncrytedData;
}
void CDES::EncryptKernel(void){
int i=1;
DWORDLONG L[17],R[17],B[9],EK,PSB;
L[0]=m_dwlData>>32;
R[0]=m_dwlData&0xffffffff;
for(i=1;i L=R[i-1];
R[i-1]=PermuteTable(R[i-1],dwlData_Expansion,48);//Expansion R
EK=R[i-1]^m_dwl_K;//E Permutation
PSB=Generate_B(EK,B);//P Permutation
R=L[i-1]^PSB;
}
R[16] m_dwlData=R[16]│L[16];
m_dwlData=PermuteTable(m_dwlData,dwlData_FP,64);
}
unsigned char* CDES::DescryptData(unsigned char *desData){
int i=1;
unsigned char *DescryptedData=new unsigned char(15);
DWORDLONG L[17],R[17],B[9],EK,PSB;
DWORDLONG dataPara;
dataPara=ProcessByte(desData,0);
dataPara=PermuteTable(dataPara,dwlData_IP,64);
R[16]=dataPara>>32;
L[16]=dataPara&0xffffffff;
for(i=16;i>=1;i--){
R[i-1]=L;
L=PermuteTable(L,dwlData_Expansion,48);//Expansion L
EK=L^m_dwl_K;//E Permutation
PSB=Generate_B(EK,B);//P Permutation
L[i-1]=R^PSB;
}
L[0] dataPara=L[0]│R[0];
dataPara=PermuteTable(dataPara,dwlData_FP,64);
//PrintBit(dataPara);
for(i=0;i DescryptedData[7-i]=(unsigned char)(dataPara&0xff);
dataPara>>=8;
}
DescryptedData[8]='\0';
printf("\nAfter Decrypted: %s\n",DescryptedData);
return DescryptedData;
}
DWORDLONG CDES::Generate_B(DWORDLONG EKPara,DWORDLONG *block){
int i,m,n;
DWORDLONG tmp=0;
for(i=8;i>0;i--){
block=EKPara&0x3f;
m=(int)(block&0x20)>>4;
m│=block&0x01;
n=(int)(block >2;
block=dwlData_S[m][n];
EKPara>>=6;
}
for(i=1;i tmp│=block;
tmp }
tmp>>=4;
tmp=PermuteTable(tmp,dwlData_P,32);
return tmp;
}
void main(void){
CDES des;
des.EncryptKey("12345678");
unsigned char *result=des.EncryptData((unsigned char*)"DemoData");
des.DescryptData(result);
}
❼ 用c语言写des加密算法
首先c语言要熟悉,然后去图书馆借一本加密解密的书,要里面有c语言des实现代码的(这种书是有的,我看到过)。论文先对加密解密的历史及发展现状进行介绍,然后着重对des加密的发展历史及原理进行阐述(以上内容要多借几本相关书综合一下用自己的语言表达出来)。然后对des的算法写个程序(可以利用书里面的程序),然后运行结果截几张图下来。最后总结一下,论文就可以了。