#define _DES_GLOBAL_
#include "common.h"	  

// 初始置换表IP
uint8_t IP_Table[64] = { 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,

                     56,48,40,32,24,16,8,0,

                     58,50,42,34,26,18,10,2,

                     60,52,44,36,28,20,12,4,

                     62,54,46,38,30,22,14,6};

//逆初始置换表IP^-1

uint8_t IP_1_Table[64] = {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,
			
			           32,0,40,8,48,16,56,24};


//扩充置换表E

uint8_t E_Table[48] = {31, 0, 1, 2, 3, 4,

                  3, 4, 5, 6, 7, 8,

                  7, 8,9,10,11,12,

                  11,12,13,14,15,16,

                  15,16,17,18,19,20,

                  19,20,21,22,23,24,

                  23,24,25,26,27,28,

                  27,28,29,30,31, 0};


//置换函数P

uint8_t P_Table[32] = {15,6,19,20,28,11,27,16,

                  0,14,22,25,4,17,30,9,

                  1,7,23,13,31,26,2,8,

                  18,12,29,5,21,10,3,24};


//S盒 

uint8_t S[8][4][16] =// 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}}};

//置换选择1

uint8_t PC_1[56] = {56,48,40,32,24,16,8,

              0,57,49,41,33,25,17,

              9,1,58,50,42,34,26,

              18,10,2,59,51,43,35,

              62,54,46,38,30,22,14,

              6,61,53,45,37,29,21,

              13,5,60,52,44,36,28,

              20,12,4,27,19,11,3};


//置换选择2

uint8_t PC_2[48] = {13,16,10,23,0,4,2,27,

              14,5,20,9,22,18,11,3,

              25,7,15,6,26,19,12,1,

              40,51,30,36,46,54,29,39,

              50,44,32,46,43,48,38,55,

              33,52,45,41,49,35,28,31};


// 对左移次数的规定

uint8_t MOVE_TIMES[16] = {1,1,2,2,2,2,2,2,1,2,2,2,2,2,2,1};


//字节转换成二进制

uint8_t ByteToBit(uint8_t ch, uint8_t bit[8])
{
    uint8_t cnt;
    for(cnt = 0;cnt < 8; cnt++)
	{
        *(bit+cnt) = (ch>>cnt)&1;
    }
    return 0;
}


// 二进制转换成字节 

uint8_t BitToByte(uint8_t bit[8],uint8_t *ch)
{
    uint8_t cnt;
    for(cnt = 0;cnt < 8; cnt++)
	{
        *ch |= *(bit + cnt)<<cnt;
    }
    return 0;
}


// 将长度为8的字符串转为二进制位串 

uint8_t Char8ToBit64(uint8_t ch[8],uint8_t bit[64])
{
    uint8_t cnt;
    for(cnt = 0; cnt < 8; cnt++)
	{       
        ByteToBit(*(ch+cnt),bit+(cnt<<3));
    }
    return 0;
}


// 将二进制位串转为长度为8的字符串

uint8_t Bit64ToChar8(uint8_t bit[64],uint8_t ch[8])
{
    uint8_t cnt;
    memset(ch,0,8);
    for(cnt = 0; cnt < 8; cnt++)
	{
        BitToByte(bit+(cnt<<3),ch+cnt);
    }
    return 0;
}


// 密钥置换1 

uint8_t DES_PC1_Transform(uint8_t key[64], uint8_t tempbts[56])
{
    uint8_t cnt;   
    for(cnt = 0; cnt < 56; cnt++)
	{
        tempbts[cnt] = key[PC_1[cnt]];
    }
    return 0;
} 
 
//密钥置换2 

uint8_t DES_PC2_Transform(uint8_t key[56], uint8_t tempbts[48])
{
    uint8_t cnt;
    for(cnt = 0; cnt < 48; cnt++)
	{
        tempbts[cnt] = key[PC_2[cnt]];
    }
    return 0;
}
//循环左移 

uint8_t DES_ROL(uint8_t data[56], uint8_t time)
{   
    uint8_t temp[56];

    //保存将要循环移动到右边的位 
    memcpy(temp,data,time);
    memcpy(temp+time,data+28,time);

    //前28位移动 
    memcpy(data,data+time,28-time);
    memcpy(data+28-time,temp,time);

    //后28位移动 
    memcpy(data+28,data+28+time,28-time);
    memcpy(data+56-time,temp+time,time);   
    return 0;
}


//IP置换

uint8_t DES_IP_Transform(uint8_t data[64])
{
    uint8_t cnt;
    uint8_t temp[64];
    for(cnt = 0; cnt < 64; cnt++)
	{
        temp[cnt] = data[IP_Table[cnt]];
    }
    memcpy(data,temp,64);
    return 0;
}

// IP逆置换 

uint8_t DES_IP_1_Transform(uint8_t data[64])
{
    uint8_t cnt;
    uint8_t temp[64];
    for(cnt = 0; cnt < 64; cnt++)
	{
        temp[cnt] = data[IP_1_Table[cnt]];
    }
    memcpy(data,temp,64);
    return 0;
}


//扩展置换 

uint8_t DES_E_Transform(uint8_t data[48])
{
    uint8_t cnt;
    uint8_t temp[48];
    for(cnt = 0; cnt < 48; cnt++)
	{
        temp[cnt] = data[E_Table[cnt]];
    }   
    memcpy(data,temp,48);
    return 0;
}

//P置换 

uint8_t DES_P_Transform(uint8_t data[32])
{
    uint8_t cnt;
    uint8_t temp[32];
    for(cnt = 0; cnt < 32; cnt++)
	{
        temp[cnt] = data[P_Table[cnt]];
    }   
    memcpy(data,temp,32);
    return 0;
}

// 异或 

uint8_t DES_XOR(uint8_t R[48], uint8_t L[48] ,uint8_t count)
{
    uint8_t cnt;
    for(cnt = 0; cnt < count; cnt++)
	{
        R[cnt] ^= L[cnt];
    }
    return 0;
}

// S盒置换 

uint8_t DES_SBOX(uint8_t data[48])
{
    uint8_t cnt;
    uint8_t line,row,output;
    uint8_t cur1,cur2;
    for(cnt = 0; cnt < 8; cnt++)
	{
        cur1 = cnt*6;
        cur2 = cnt<<2;
        // 计算在S盒中的行与列 
        line = (data[cur1]<<1) + data[cur1+5];
        row = (data[cur1+1]<<3) + (data[cur1+2]<<2)
            + (data[cur1+3]<<1) + data[cur1+4];
        output = S[cnt][line][row];
        // 化为2进制 
        data[cur2] = (output&0X08)>>3;
		data[cur2+1] = (output&0X04)>>2;
        data[cur2+2] = (output&0X02)>>1;
        data[cur2+3] = output&0x01;
    }   
    return 0;
}

//交换 

uint8_t DES_Swap(uint8_t left[32], uint8_t right[32])
{
    uint8_t temp[32];
    memcpy(temp,left,32);   
    memcpy(left,right,32);   
    memcpy(right,temp,32);
    return 0;
} 

//生成子密钥

uint8_t DES_MakeSubKeys(uint8_t key[64],uint8_t subKeys[16][48])
{
	uint8_t temp[56];
	uint8_t cnt;
	DES_PC1_Transform(key,temp);// PC1置换
	for(cnt = 0; cnt < 16; cnt++) //16轮跌代，产生16个子密钥
	{
		DES_ROL(temp,MOVE_TIMES[cnt]);// 循环左移 
		DES_PC2_Transform(temp,subKeys[cnt]);//PC2置换，产生子密钥
	}
	return 0;
}

//加密单个分组 

uint8_t DES_EncryptBlock(uint8_t plainBlock[8], uint8_t subKeys[16][48], uint8_t cipherBlock[8])
{
    uint8_t plainBits[64];
    uint8_t copyRight[48];
    uint8_t cnt;
    Char8ToBit64(plainBlock,plainBits);       
    //初始置换（IP置换） 
    DES_IP_Transform(plainBits);
    // 16轮迭代 
    for(cnt = 0; cnt < 16; cnt++)
	{       
        memcpy(copyRight,plainBits+32,32);
        DES_E_Transform(copyRight);			// 将右半部分进行扩展置换，从32位扩展到48位
        DES_XOR(copyRight,subKeys[cnt],48);	// 将右半部分与子密钥进行异或操作 
        DES_SBOX(copyRight);				// 异或结果进入S盒，输出32位结果 
        DES_P_Transform(copyRight);			// P置换
        DES_XOR(plainBits,copyRight,32);	//将明文左半部分与右半部分进行异或 
        if(cnt != 15)
		{
            DES_Swap(plainBits,plainBits+32);//最终完成左右部的交换 
        }
    }
    DES_IP_1_Transform(plainBits);			//逆初始置换（IP^1置换）
    Bit64ToChar8(plainBits,cipherBlock);
    return 0;
}

// 解密单个分组
uint8_t DES_DecryptBlock(uint8_t cipherBlock[8], uint8_t subKeys[16][48],uint8_t plainBlock[8])
{
    uint8_t cipherBits[64];
    uint8_t copyRight[48];
    int8_t cnt;
    Char8ToBit64(cipherBlock,cipherBits);       
    //初始置换（IP置换）
    DES_IP_Transform(cipherBits);
    // 16轮迭代 
    for(cnt = 15; cnt >= 0; cnt--)
	{       
        memcpy(copyRight,cipherBits+32,32);
        //将右半部分进行扩展置换，从32位扩展到48位 
        DES_E_Transform(copyRight);
        // 将右半部分与子密钥进行异或操作 
        DES_XOR(copyRight,subKeys[cnt],48);       
        //异或结果进入S盒，输出32位结果 
        DES_SBOX(copyRight);
        // P置换 
        DES_P_Transform(copyRight);       
        //将明文左半部分与右半部分进行异或 
        DES_XOR(cipherBits,copyRight,32);
        if(cnt != 0)
		{
            // 最终完成左右部的交换
            DES_Swap(cipherBits,cipherBits+32);
        }
    }
    // 逆初始置换（IP^1置换）
    DES_IP_1_Transform(cipherBits);
    Bit64ToChar8(cipherBits,plainBlock);
    return 0;
}


//加密文件

uint8_t DES_Encrypt(uint8_t *plainFile, uint8_t *keyStr,uint8_t *cipherFile)
{
    uint8_t keyBlock[8],bKey[64],subKeys[16][48];

    memcpy(keyBlock,keyStr,8);							 // 设置密钥
    Char8ToBit64(keyBlock,bKey);						 // 将密钥转换为二进制流
    DES_MakeSubKeys(bKey,subKeys);						  //生成子密钥

	DES_EncryptBlock(plainFile,subKeys,cipherFile);  	
	return OK;
}

//解密文件 
uint8_t DES_Decrypt(uint8_t *cipherFile, uint8_t *keyStr,uint8_t *plainFile)
{
//	uint8_t plainBlock[8],cipherBlock[8],
    uint8_t bKey[64],keyBlock[8],subKeys[16][48];

    memcpy(keyBlock,keyStr,8);							//设置密钥 
    Char8ToBit64(keyBlock,bKey);						//将密钥转换为二进制流
    DES_MakeSubKeys(bKey,subKeys);						//生成子密钥 

	DES_DecryptBlock(cipherFile,subKeys,plainFile);                       
	return OK;
}

/**/