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C语言的DES算法

菜鸟
2011-08-26 17:54:56 打赏

/* Permuted Choice 1 (PC-1) */
const unsigned char 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
};

/* Permuted Choice 2 (PC-2) */
const unsigned char 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
};

const unsigned char SHIFTTABLE[16] = {1,1,2,2,2,2,2,2,1,2,2,2,2,2,2,1};

/* Initial Permutation (IP) */
const unsigned char IP[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
};

/* Final Permutation (IP**-1) */
const unsigned char INVIP[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
};

/* Expansion (E) */
const unsigned char 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
};

/* Permutation P */
const unsigned char P[32] = { 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
};

/* Substitution Box 1 - 16 */
const unsigned char SBOXES[8][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
},
{
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
}
};


/*----------------------------------------------------------------------------
程序名称:void Memory_Copy(unsigned char *Destination_Addr,unsigned char *Source_Addr,unsigned char Data_Lent)
功能:通用置换函数
入口参数:
Destination_Addr:拷贝的目的地址
Source_Addr :拷贝的源地址
Data_Lent :需要拷贝的数据长度
出口参数:
备注:
----------------------------------------------------------------------------*/
void memcpy( char *Destination_Addr,char *Source_Addr,unsigned char Data_Lent)
{
unsigned char i;

for (i = 0; i < Data_Lent; i++)
{
*Destination_Addr = *Source_Addr;

Destination_Addr++;
Source_Addr++;

}
}

char GetBit (const char * DataTab, const char Index)
{
char aBit;

aBit = 128 >> (Index % 8);

if (DataTab[Index / 8] & aBit)
{
return 1;
}
else
{
return 0;
}
}


void SetBit (char * DataTab, const char Index, const char Value)
{
char aBit;

aBit = 128 >> (Index % 8);

if(Value)
{
DataTab[Index / 8] |= aBit;
}
else
{
DataTab[Index / 8] &= ~aBit;
}
}

void F(const char * FR, const char * FK, char * TotalOut)
{
char Temp1[48];
char Temp2[32];
int n, h, i, j, Row, Column;

for( n = 0; n < 48; n++)
{
Temp1[n] = FR[E[n] - 1] ^ FK[n];
}

for( n = 0; n < 8; n++)
{
i = n * 6;
j = n * 4;
Row = Temp1[i] * 2 + Temp1[i + 5];
Column = Temp1[i + 1] * 8 + Temp1[i + 2] * 4 + Temp1[i + 3] * 2 + Temp1[i + 4];

for( h = 0; h < 4; h++)
{
switch (h)
{
case 0:
{
Temp2[j + h] = (SBOXES[n][Row][Column] & 8) / 8;
break;
}
case 1:
{
Temp2[j + h] = (SBOXES[n][Row][Column] & 4) / 4;
break;
}
case 2:
{
Temp2[j + h] = (SBOXES[n][Row][Column] & 2) / 2;
break;
}
case 3:
{
Temp2[j + h] = (SBOXES[n][Row][Column] & 1);
break;
}
}
}
}
for( n = 0; n < 32; n++)
{
TotalOut[n] = Temp2[P[n] - 1];
}
}

void Shift (char * SubKeyPart)
{
char n, b;

b = SubKeyPart[0];

for( n = 0; n < 27; n++)
{
SubKeyPart[n] = SubKeyPart[n + 1];
}

SubKeyPart[27] = b;
}

void SubKey (const char Round, char * SubKeyData, char * C, char * D)
{
char n, b;

for( n = 0; n < SHIFTTABLE[Round]; n++)
{
Shift (C);
Shift (D);
}
for( n = 0; n < 48; n++)
{
b = PC_2[n] - 1;

if (b < 28)
{
SubKeyData[n] = C[b];
}
else
{
SubKeyData[n] = D[b - 28];
}
}
}

void Des(char * DesData,const char * DesKey,const char Encrypt)
{
char InputValue[64],OutputValue[64];
char RoundKeys[16][48];
char L[32], R[32], FunctionResult[32];
char C[28], D[28];
char n, b, Round;

for ( n = 0; n < 64; n++)
{
InputValue[n] = GetBit(DesData,n);
}
for ( n = 0; n < 64; n++)
{
if (n < 32)
{
L[n] = InputValue[IP[n] - 1];
}
else
{ R[n - 32] = InputValue[IP[n] - 1];
}
}
for ( n = 0; n < 28; n++)
{
C[n] = GetBit(DesKey,PC_1[n] - 1);
D[n] = GetBit(DesKey,PC_1[n + 28] - 1);
}
for ( n = 0; n < 16; n++)
{
SubKey(n,RoundKeys[n],C,D);
}
for ( Round = 0; Round < 16; Round++)
{
if ( Encrypt )
{
F(R,RoundKeys[Round],FunctionResult);
}
else
{
F(R,RoundKeys[15 - Round],FunctionResult);
}
for( n = 0; n < 32; n++)
{
FunctionResult[n] = FunctionResult[n] ^ L[n];
}
memcpy(L,R,sizeof(R));
memcpy(R,FunctionResult,sizeof(R));
}
for ( n = 0; n < 64; n++)
{
b = INVIP[n] - 1;
if( b < 32 )
{
OutputValue[n] = R[b];
}
else
{
OutputValue[n] = L[b - 32];
}
}
for( n = 0; n < 64; n++)
{
SetBit(DesData,n,OutputValue[n]);
}
}




关键词: 语言 算法 const unsigned

菜鸟
2013-12-16 11:04:20 打赏
2楼
EXCELLENT!

院士
2013-12-16 13:47:26 打赏
3楼
这个东西回家去验证一下

专家
2013-12-16 18:20:22 打赏
4楼
学习了,非常强大

专家
2013-12-16 18:22:26 打赏
5楼
是那种算法?

高工
2013-12-16 19:37:49 打赏
6楼
百度了一下DES算法,感觉很牛B的样子,来看看

菜鸟
2013-12-19 22:54:43 打赏
7楼
我们用AES算法,FPGA加密,C解密

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