📄 des.cpp
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pstroutput+=sprintf(pstroutput,"解密步骤F处理B：密钥字节的F处理...........\n");//) & 07
pstroutput+=sprintf(pstroutput,"解密步骤F处理B-%d-1：第%d个6位密钥：",KeyByte,KeyByte);//) & 07
for(int i=0;i<6;i++)
{
pstroutput+=sprintf(pstroutput,"%d", subKey[KeyByte] & (byteBit[i%6+2 ]) ? 1:0);
if ((i+1)%6==0) pstroutput+=sprintf(pstroutput,"\n");
}
pstroutput+=sprintf(pstroutput,"解密步骤F处理B-%d-1：第%d个6位数据：",KeyByte,KeyByte);//) & 07
for( i=0;i<6;i++)
{
if(KeyByte<7) pstroutput+=sprintf(pstroutput,"%d", rt0 >> (26-KeyByte*4) & (byteBit[i%6+2 ]) ? 1:0);
else pstroutput+=sprintf(pstroutput,"%d", rt1 & (byteBit[i%6+2 ]) ? 1:0);
if ((i+1)%6==0) pstroutput+=sprintf(pstroutput,"\n");
}
pstroutput+=sprintf(pstroutput,"解密步骤F处理B-%d-2：第%d次异或6位：",KeyByte,KeyByte);//) & 07
for(i=0;i<6;i++)
{
if(KeyByte<7) pstroutput+=sprintf(pstroutput,"%d", (rt0 >> (26-KeyByte*4) ^ subKey[KeyByte]) & (byteBit[i%6+2 ]) ? 1:0);
else pstroutput+=sprintf(pstroutput,"%d", (rt1 ^ subKey[KeyByte]) & (byteBit[i%6+2 ]) ? 1:0);
if ((i+1)%6==0) pstroutput+=sprintf(pstroutput,"\n");
}
}
if(KeyByte<7) XorValue=((rt0 >> (26-KeyByte*4)) ^ subKey[KeyByte]);
else XorValue=(rt1 ^ subKey[KeyByte]);
if (doEncrypt)pstroutput+=sprintf(pstroutput,"加密步骤F处理B-%d-3：第%d字节处理S盒代换和P重排：",KeyByte,KeyByte);//) & 07
else pstroutput+=sprintf(pstroutput,"解密步骤F处理B-%d-3：第%d字节处理S盒代换和P重排：",KeyByte,KeyByte);//) & 07
rowCol = (XorValue & 32) | ((XorValue & 1) ? 16 : 0) | ((XorValue >> 1) & 0xf);//重行位和列位:b0b5b1b2b3b4
if (doEncrypt)pstroutput+=sprintf(pstroutput,"用S[%d]盒中第%d号值：%d取代\n", KeyByte,rowCol+1,si[KeyByte][rowCol]);
for(int i=0;i<4;i++)//每个取代值有4位
{
if (si[KeyByte][rowCol] & byteBit[i+4])//取得输出位
{
if (doEncrypt)pstroutput+=sprintf(pstroutput,"此位为1，该在32位中的第%d位；P排列换到第%d位\n", KeyByte*4+i+1,pBox[KeyByte*4+i]+1);
rValtwx[KeyByte] |= 1L << (31 - pBox[4 * KeyByte + i]);//进行P排列，并累加
}
}
if (doEncrypt)
{
pstroutput+=sprintf(pstroutput,"P排列后得到的32位：\n");//) & 07
for(i=0;i<4;i++)
{//输出编号
for(int j=0;j<8;j++)pstroutput+=sprintf(pstroutput,"%d",j+1);
pstroutput+=sprintf(pstroutput," ");//8位一制表符
}
pstroutput+=sprintf(pstroutput,"\n");
for(i=0;i<4;i++)
{
for(int j=0;j<8;j++)pstroutput+=sprintf(pstroutput,"%u",(rValtwx[KeyByte]>>(3-i)*8 & byteBit[j]) ? 1:0);
pstroutput+=sprintf(pstroutput," ");//8位一制表符
if ((i+1)%4==0) pstroutput+=sprintf(pstroutput,"\n");
}
}
else
{
pstroutput+=sprintf(pstroutput,"P排列后得到的32位：\n");//) & 07
for(i=0;i<4;i++)
{//输出编号
for(int j=0;j<8;j++)pstroutput+=sprintf(pstroutput,"%d",j+1);
pstroutput+=sprintf(pstroutput," ");//8位一制表符
}
pstroutput+=sprintf(pstroutput,"\n");
for(i=0;i<4;i++)
{
for(int j=0;j<8;j++)pstroutput+=sprintf(pstroutput,"%u",(rValtwx[KeyByte]>>(3-i)*8 & byteBit[j]) ? 1:0);
pstroutput+=sprintf(pstroutput," ");//8位一制表符
if ((i+1)%4==0) pstroutput+=sprintf(pstroutput,"\n");
}
}
rVal |=rValtwx[KeyByte];
}
/* rVal |= sp[0][((rt0 >> 26) ^ *subKey++) & 0x3f];
rVal |= sp[1][((rt0 >> 22) ^ *subKey++) & 0x3f];
rVal |= sp[2][((rt0 >> 18) ^ *subKey++) & 0x3f];
rVal |= sp[3][((rt0 >> 14) ^ *subKey++) & 0x3f];
rVal |= sp[4][((rt0 >> 10) ^ *subKey++) & 0x3f];
rVal |= sp[5][((rt0 >> 6) ^ *subKey++) & 0x3f];
rVal |= sp[6][((rt0 >> 2) ^ *subKey++) & 0x3f];
rVal |= sp[7][(rt1 ^ *subKey) & 0x3f];
*/
if (doEncrypt)
{
pstroutput+=sprintf(pstroutput,"步骤F处理C：8个4位或运算后得到的32位：\n");//) & 07
for(int i=0;i<4;i++)
{
for(int j=0;j<8;j++)pstroutput+=sprintf(pstroutput,"%u",(rVal>>(3-i)*8 & byteBit[j]) ? 1:0);
pstroutput+=sprintf(pstroutput," ");//8位一制表符
if ((i+1)%4==0) pstroutput+=sprintf(pstroutput,"\n");
}
}
return rVal;
} /* F() */
/************************************************************************
* Function name : PermInit
* Description : Initialize a perm array
* :
* Parameters :
* Returns :
* Author : Richard Shen
* ----------------------------------------------------------------------
* Date By Description
* ----------------------------------------------------------------------
* 20Jan99 RCS Created.
************************************************************************/
//初始排列
void PermInit(char perm[16][16][8], const char p[64])
{
int i, j, k, m, n;
/* Clear the permutation array */
for (i = 0; i < 16; i++)
{
for (j = 0; j < 16; j++)
{
for (k = 0; k < 8; k++)
perm[i][j][k]=0;
} /* end of for j */
} /* end of for i */
for (i = 0; i < 16; i++) /* Each input nibble position */
{
for (j = 0; j < 16; j++) /* Each possible input nibble */
{
for (k = 0; k < 64; k++) /* Each output bit position */
{
n = p[k] - 1;//常表中，是从1开始所以-1;
/* Does this bit come from input position ? */
if ((n >> 2) != i)
continue; /* No, bit k is 0 */
if (!(j & nibbleBit[n & 3]))
continue;
//m第几位在字节中的位置如k=1在第1位
m = k & 07; /* Which bit is this in the byte */
//k最多6位，k>>3取得字节位置。设置第几位
perm[i][j][k >> 3] |= byteBit[m];
} /* end of for k */
} /* end of for j */
} /* end of for i */
return;
} /* PermInit() */
/************************************************************************
* Function name : SPInit
* Description : Initialize the lookup table for the combined S and P
* : boxes
* Parameters : -
* Returns : -
* Author : Richard Shen
* ----------------------------------------------------------------------
* Date By Description
* ----------------------------------------------------------------------
* 20Jan99 RCS Created.
************************************************************************/
void SPInit(void)
{
int p, i, s, j, rowCol;
long val;
/* Compute pbox, the inverse of p32i. This is easier to work with. */
//求P排列的逆排列：如将第9项放到第1位。
for (p = 0; p < 32; p++)
{
for (i = 0;i < 32; i++)
{
if (p32i[i] - 1 == p) //p32i[i]是从1起的，
{
pBox[p] = i;
break;
} /* end of if */
} /* end of for i */
} /* end of for p */
/* pstroutput+=sprintf(pstroutput,"P盒的逆排列：\n");//) & 07
for (p = 0; p < 32; p++)
{
pstroutput+=sprintf(pstroutput,"%d ", pBox[p]);
if ((p+1)%8==0) pstroutput+=sprintf(pstroutput,"\n");
}
*/
for (s = 0; s < 8; s++) /* For each S-box */
{
int n(0);
// if (s==0)pstroutput+=sprintf(pstroutput,"搬到相应位：\n");
for(i = 0; i < 64; i++) /* For each possible input */
{
val = 0;//将所有的32位初始化为0，P盒替代后是32位
/*
The row number is formed from the first and last
bits; the column number is from the middle 4.
*/
// i & 32取第0位，((i & 1) ? 16 : 0)取第5位，如为1，相当于乘16，
//(i >> 1) & 0xf取中间4位，三者或起来，而成了行列，12为行，3456为列了，
//换位05 取最高位 //取最低位，但基数是16, //右移1位，再取4位即中间四位。
//将每个i表示左面位是行位，右4位是列序的形式。
rowCol = (i & 32) | ((i & 1) ? 16 : 0) | ((i >> 1) & 0xf);
//rowCol本身是一个整数才能反映在S盒中的顺序数：从左到右，从上到下。
for (j = 0; j < 4; j++) /* For each output bit */
{
//每个元素值由4位组成，这里要决定各位
if (si[s][rowCol] & (8 >> j))//si[s][rowCol]书中S盒，如果该位为1
{
if ((n+1)%8==0) val |= 1L << (31 - pBox[4 * s + j]);//则要把1搬到相应位且都或起来。
//本来是在（ 4 * s + j）的位置但是移位的最高位在最左边所以32-（ 4 * s + j）
//
}
} /* end of for */
sp[s][i] = val;
} /* end of for */
} /* end of for s */
return;
} /* SPInit() */
/************************************************************************
* Function name : ByteSwap
* Description : Byte swap a long
* :
* Parameters : x
* Returns : ...
* Author : Richard Shen
* ----------------------------------------------------------------------
* Date By Description
* ----------------------------------------------------------------------
* 20Jan99 RCS Created.
************************************************************************/
//变反序为正序，例:int temp=0x12345678在intel系统内存中为：78563412
//通过此函数变为:12345678
//因为在实现时，将字符串强转为整型来处理。
unsigned long ByteSwap(unsigned long x)
{
//一个整型有4个字节，0字节与3字节互换
char tmp;
char *cp;
cp = (char *)&x;
tmp = cp[3];
cp[3] = cp[0];
cp[0] = tmp;
//0，1字节互换
tmp = cp[2];
cp[2] = cp[1];
cp[1] = tmp;
return x;
} /* ByteSwap() */
int main(int argc, char* argv[])
{
unsigned char key[9]="12345678";
unsigned char message[9]="ABCDEFGH";
// char stroutput[104857];
//可以看到C当中字串型是正序，而整型是反序存储。
int i(2049);
int *p=&i;
pstroutput+=sprintf(pstroutput,"Plain ASCII String:%s \n",message);
// pstroutput+=sprintf(pstroutput,"\n");
pstroutput+=sprintf(pstroutput,"Plain Bit String: \n");
for ( i=0;i<8;i++) { if(i%2==0) pstroutput+=sprintf(pstroutput,"\t");pstroutput+=sprintf(pstroutput,"%0X",message[i]);}
pstroutput+=sprintf(pstroutput,"\n");
pstroutput+=sprintf(pstroutput,"Key ASCII String:%s \n",key);
pstroutput+=sprintf(pstroutput,"Key Bit String: \n");
for ( i=0;i<8;i++) { if(i%2==0) pstroutput+=sprintf(pstroutput,"\t");pstroutput+=sprintf(pstroutput,"%0X",key[i]);;}
pstroutput+=sprintf(pstroutput,"\n");
DesEncrypt(key,message);
pstroutput+=sprintf(pstroutput,"密文Cipher Bit String:");
for (i=0;i<8;i++)
{
if(i%2==0) pstroutput+=sprintf(pstroutput,"\t");
pstroutput+=sprintf(pstroutput,"0X%0X",message[i]);
}
pstroutput+=sprintf(pstroutput,"\n");
DesDecrypt(key,message);
pstroutput+=sprintf(pstroutput,"Decrypted Bit String:");
printf(pstroutput,"Decrypted Bit String:");
for (i=0;i<8;i++)
{
if(i%2==0)
{
pstroutput+=sprintf(pstroutput,"\t");
printf("\t");
}
pstroutput+=sprintf(pstroutput,"%0X",message[i]);
printf("%0X",message[i]);
}
pstroutput+=sprintf(pstroutput,"\n");printf("\n");
pstroutput+=sprintf(pstroutput,"Decrypted ASCII String:%s \n",message);
printf("Decrypted ASCII String:%s \n",message);
printf("\n");
pstroutput+=sprintf(pstroutput,"\n");
// printf("%s",pstroutput0);//输出到屏幕
fstream filetemp;
char strtempfile[256]={0};
GetCurrentDirectory(256,strtempfile);
char strfilename[256]="\\Des全过程.txt";
strcat(strtempfile,strfilename);
filetemp.open(strtempfile,ios::out,filebuf::openprot);
filetemp.write((unsigned char const *)pstroutput0,pstroutput-pstroutput0);
filetemp.close();
free(pstroutput0);
return 0;
}
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