AES.cpp

#define _CRT_SECURE_NO_WARNINGS

#include <stdio.h>
void output(unsigned char* blk_99)
{
	
	for (int i = 0; i < 16; i++)
	{
		printf("%02x ", blk_99[i]);
	}
	printf("\n");
}
/*aes_small.c*/
//辅助矩阵
/*s盒矩阵：The AES Substitution Table*/// 256 位的密匙256 位支持长度为32 个字符
static const unsigned char sbox[256] = {	//static:内部变量  const：只读，不可变常量
	0x63,0x7c,0x77,0x7b,0xf2,0x6b,0x6f,0xc5,
	0x30,0x01,0x67,0x2b,0xfe,0xd7,0xab,0x76,
	0xca,0x82,0xc9,0x7d,0xfa,0x59,0x47,0xf0,
	0xad,0xd4,0xa2,0xaf,0x9c,0xa4,0x72,0xc0,
	0xb7,0xfd,0x93,0x26,0x36,0x3f,0xf7,0xcc,
	0x34,0xa5,0xe5,0xf1,0x71,0xd8,0x31,0x15,
	0x04,0xc7,0x23,0xc3,0x18,0x96,0x05,0x9a,
	0x07,0x12,0x80,0xe2,0xeb,0x27,0xb2,0x75,
	0x09,0x83,0x2c,0x1a,0x1b,0x6e,0x5a,0xa0,
	0x52,0x3b,0xd6,0xb3,0x29,0xe3,0x2f,0x84,
	0x53,0xd1,0x00,0xed,0x20,0xfc,0xb1,0x5b,
	0x6a,0xcb,0xbe,0x39,0x4a,0x4c,0x58,0xcf,
	0xd0,0xef,0xaa,0xfb,0x43,0x4d,0x33,0x85,
	0x45,0xf9,0x02,0x7f,0x50,0x3c,0x9f,0xa8,
	0x51,0xa3,0x40,0x8f,0x92,0x9d,0x38,0xf5,
	0xbc,0xb6,0xda,0x21,0x10,0xff,0xf3,0xd2,
	0xcd,0x0c,0x13,0xec,0x5f,0x97,0x44,0x17,
	0xc4,0xa7,0x7e,0x3d,0x64,0x5d,0x19,0x73,
	0x60,0x81,0x4f,0xdc,0x22,0x2a,0x90,0x88,
	0x46,0xee,0xb8,0x14,0xde,0x5e,0x0b,0xdb,
	0xe0,0x32,0x3a,0x0a,0x49,0x06,0x24,0x5c,
	0xc2,0xd3,0xac,0x62,0x91,0x95,0xe4,0x79,
	0xe7,0xc8,0x37,0x6d,0x8d,0xd5,0x4e,0xa9,
	0x6c,0x56,0xf4,0xea,0x65,0x7a,0xae,0x08,
	0xba,0x78,0x25,0x2e,0x1c,0xa6,0xb4,0xc6,
	0xe8,0xdd,0x74,0x1f,0x4b,0xbd,0x8b,0x8a,
	0x70,0x3e,0xb5,0x66,0x48,0x03,0xf6,0x0e,
	0x61,0x35,0x57,0xb9,0x86,0xc1,0x1d,0x9e,
	0xe1,0xf8,0x98,0x11,0x69,0xd9,0x8e,0x94,
	0x9b,0x1e,0x87,0xe9,0xce,0x55,0x28,0xdf,
	0x8c,0xa1,0x89,0x0d,0xbf,0xe6,0x42,0x68,
	0x41,0x99,0x2d,0x0f,0xb0,0x54,0xbb,0x16,
};
//逆向S 盒矩阵

/*轮常量表 The key schedule rcon table*/
static const unsigned char Rcon[10] = {
	0x01,0x02,0x04,0x08,0x10,0x20,0x40,0x80,0x1b,0x36 };

//辅助函数
/*有限域*2乘法 The x2time() function */
static unsigned char x2time(unsigned char x)
{
	if (x & 0x80)
	{
		return (((x << 1) ^ 0x1B) & 0xFF);
	}
	return x << 1;
}
/*有限域*3乘法 The x2time() function */
static unsigned char x3time(unsigned char x)
{
	return (x2time(x) ^ x);
}
/*有限域*4乘法 The x4time() function */
static unsigned char x4time(unsigned char x)
{
	return (x2time(x2time(x)));
}
/*有限域*8乘法 The x8time() function */
static unsigned char x8time(unsigned char x)
{
	return (x2time(x2time(x2time(x))));
}
/*有限域9乘法 The x9time() function */
static unsigned char x9time(unsigned char x)	//9:1001
{
	return (x8time(x) ^ x);
}
/*有限域*B乘法 The xBtime() function */
static unsigned char xBtime(unsigned char x)	//B:1011
{
	return (x8time(x) ^ x2time(x) ^ x);
}
/*有限域*D乘法 The xDtime() function */
static unsigned char xDtime(unsigned char x)	//D:1101
{
	return (x8time(x) ^ x4time(x) ^ x);
}
/*有限域*E乘法 The xEtime() function */
static unsigned char xEtime(unsigned char x)	//E:1110
{
	return (x8time(x) ^ x4time(x) ^ x2time(x));
}

/****************************************************************************************************************/
/*第三类操作：列混合操作 MixColunms_99: Process the entire block*/
static void MixColunms_99(unsigned char *col)//列混合
{
	unsigned char tmp[4], xt[4];
	int i;
	for (i = 0; i < 4; i++, col += 4)  //col代表一列的基地址，col+4:下一列的基地址
	{
		
		tmp[0] = x2time(col[0]) ^ x3time(col[1]) ^ col[2] ^ col[3];	//2 3 1 1
		tmp[1] = col[0] ^ x2time(col[1]) ^ x3time(col[2]) ^ col[3];	//1 2 3 1
		tmp[2] = col[0] ^ col[1] ^ x2time(col[2]) ^ x3time(col[3]);	//1 1 2 3
		tmp[3] = x3time(col[0]) ^ col[1] ^ col[2] ^ x2time(col[3]);	//3 1 1 2
		//修改后的值 直接在原矩阵上修改
		col[0] = tmp[0];
		col[1] = tmp[1];
		col[2] = tmp[2];
		col[3] = tmp[3];
	}
}

/*第二类操作：行移位：行左循环移位 ShiftRows_99:Shifts the entire block*/
static void ShiftRows_99(unsigned char *col)//正向行移位
{
	/*
		1 5  9 13				5  9 13 1
		2 6 10 14				10 14 2 6
		3 7 11 15				15 3 7 11
		4 8 12 16				16 4 8 12
	*/
	unsigned char t;
	/*1nd row*///左移1位
	t = col[1]; col[1] = col[5]; col[5] = col[9]; col[9] = col[13]; col[13] = t;
	/*2rd row*///左移2位，交换2次数字来实现
	t = col[2]; col[2] = col[10]; col[10] = t;
	t = col[6]; col[6] = col[14]; col[14] = t;
	/*3th row*///左移3位，相当于右移1次
	t = col[15]; col[15] = col[11]; col[11] = col[7]; col[7] = col[3]; col[3] = t;
	/*4th row*/	//第4行不移位
}

/*第一类操作：s盒字节代换替换 SubBytes_99*/
static void SubBytes_99(unsigned char *col)//字节代换
{
	int x;
	for (x = 0; x < 16; x++)
	{
		col[x] = sbox[col[x]];
	}
}
//逆向字节代换

/*第四类操作：轮密钥加 AddRoundKey_99*/
static void AddRoundKey_99(unsigned char *col, unsigned char *expansionkey, int round)//密匙加
{
	
	int x;
	for (x = 0; x < 16; x++)	//每1轮操作：4*32bit密钥 = 16个字节密钥
	{
		col[x] ^= expansionkey[(round << 4) + x];
	}
}
/* AES加密总函数 10轮4类操作 Encrypt a single block with Nr Rounds(10,12,14)*/
void AesEncrypt(unsigned char *blk_99, unsigned char *expansionkey, int Nr)//加密一个区块
{
	//输入blk_99原文，直接在上面修改，输出blk_99密文
	//输入skey：
	//输入Nr = 10轮
	int round=0;
	//第1轮之前：轮密钥加
	AddRoundKey_99(blk_99, expansionkey, 0);//轮密钥加
	printf("轮密钥加第%d轮", round);
	output(blk_99);

	//第1-9轮：4类操作：字节代换、行移位、列混合、轮密钥加
	for (round = 1; round <= (Nr - 1); round++)
	{
		SubBytes_99(blk_99);		//输入16字节数组，直接在原数组上修改
		printf("字节代换第%d轮", round);
		output(blk_99);
		ShiftRows_99(blk_99);	
		printf("行移位第%d轮", round);
		output(blk_99);
		MixColunms_99(blk_99);
		printf("列混合第%d轮", round);
		output(blk_99);
		AddRoundKey_99(blk_99, expansionkey, round);
		printf("轮密钥加第%d轮", round);
		output(blk_99);
	}
	//第10轮：不进行列混合
	SubBytes_99(blk_99);
	ShiftRows_99(blk_99);
	AddRoundKey_99(blk_99, expansionkey, Nr);
}

void ScheduleKey(unsigned char *inkey, unsigned char *outkey, int Nk, int Nr)//安排一个保密密钥使用
{
	
	unsigned char temp[4], t;
	int x, i;
	
	for (i = 0; i < (4 * Nk); i++)
	{
		outkey[i] = inkey[i];
	}
	//第1-10组：[4-43]
	i = Nk;
	while (i < (4 * (Nr + 1))) //i=4~43 WORD 32bit的首字节地址，每一个4字节
	{
		for (x = 0; x < 4; x++)
			temp[x] = outkey[(4 * (i - 1)) + x];	//i：32bit的首字节地址
		//i是4的倍数的时候
		if (i%Nk == 0)
		{
			/*字循环：循环左移1字节 RotWord()*/
			t = temp[0]; temp[0] = temp[1]; temp[1] = temp[2]; temp[2] = temp[3]; temp[3] = t;
			/*字节代换：SubWord()*/
			for (x = 0; x < 4; x++)
			{
				temp[x] = sbox[temp[x]];
			}
			/*轮常量异或：Rcon[j]*/
			temp[0] ^= Rcon[(i / Nk) - 1];
		}
		for (x = 0; x < 4; x++)
		{
			outkey[(4 * i) + x] = outkey[(4 * (i - Nk)) + x] ^ temp[x];
		}
		++i;
	}
}
int main(void) {

	unsigned char expansionkey[15 * 16];
	int i;
	int j;
	unsigned char input[16]={ 0x20,0x18,0x12,0x20,0x99,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x0E };
	unsigned char key[16] = { 0xa0,0xfa,0xfe,0x17,0x88,0x54,0x2c,0xb1,0x23,0xa3,0x39,0x39,0x2a,0x6c,0x76,0x05 };

	ScheduleKey(key, expansionkey, 4, 10);	//1、密钥扩展生成
	AesEncrypt(input, expansionkey, 10);		//2、AES 加密
	printf("AesEncrypt text is: ");	//输出密码文件
	for (i = 0; i < 16; i++)
	{
		printf("%02x ", input[i]);
	}
	printf("\n");
	printf("\n");
	while (1);
	return 0;
}