February 3, 2022

SM4-P.Z

先贴个我手打的源码

SM4

SM4.h

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#ifndef SM4_H
#define SM4_H

#define ENC 1
#define DEC 0

/**
 *	模式与密钥 
 */ 
typedef struct
{
	int mode;					 
	unsigned long sk[32]; 
} Context;

/**
 *	参数 ctx: 代初始化的结构体 
 *	参数 key: 16字节密钥
 */
void SetKeyEnc(Context * ctx, unsigned char key[16]);

/**
 *	参数 ctx: 代初始化的结构体
 *	参数 key: 16字节密钥
 */
void SetKeyDec(Context * ctx, unsigned char key[16]);

/**
 *	参数 ctx: 结构体
 *	参数 mode: 解密或解密模式
 *	参数 len: input的长度
 *	参数 input: 明文字符串
 *	参数 output: 加密后字符串
 */
void CryptEBC(Context * ctx, int mode, int len, unsigned char * input, unsigned char * output);   

#endif

SM4.c

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#include <stdio.h>
#include <string.h>
#include "SM4.h"

/**
 *	作用: 无符号长整型数组 转 无符号长整型 
 */
#define GET_ULONG(n, b, i)							\
	(n) = ( (unsigned long) (b)[(i    )] << 24 )	\
		| ( (unsigned long) (b)[(i + 1)] << 16 )	\
		| ( (unsigned long) (b)[(i + 2)] << 8  )	\
		| ( (unsigned long) (b)[(i + 3)] 	   ); 	\

/**
 *	作用: 无符号长整型 转 无符号长整型数组
 */ 
#define PUT_ULONG(n, b, i)							\
{													\
	(b)[(i)    ] = (unsigned char) ( (n) >> 24 );	\
	(b)[(i) + 1] = (unsigned char) ( (n) >> 16 );	\
	(b)[(i) + 2] = (unsigned char) ( (n) >> 8  );	\
	(b)[(i) + 3] = (unsigned char) ( (n)	   );	\
}													

/**
 *	作用: 参数 x 左移参数 n 位 
 */ 
#define SHL(x, n) ( ((x) & 0xFFFFFFFF) << n )

/**
 *	作用: 参数 x 逻辑左移参数 n 位 
 */ 
#define ROTL(x, n) ( SHL((x), n) | ((x) >> (32 - n)) )

/**
 *	作用: 两个参数交换 
 */ 
#define SWAP(a, b) { unsigned t = a; a = b; b = t; t = 0; } 

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

/**
 *	密钥用常量 
 */ 
static const unsigned long FK[4] = {0xa3b1bac6,0x56aa3350,0x677d9197,0xb27022dc};

/**
 *	密钥用常量 
 */ 
static const unsigned long CK[32] =
{
0x00070e15,0x1c232a31,0x383f464d,0x545b6269,
0x70777e85,0x8c939aa1,0xa8afb6bd,0xc4cbd2d9,
0xe0e7eef5,0xfc030a11,0x181f262d,0x343b4249,
0x50575e65,0x6c737a81,0x888f969d,0xa4abb2b9,
0xc0c7ced5,0xdce3eaf1,0xf8ff060d,0x141b2229,
0x30373e45,0x4c535a61,0x686f767d,0x848b9299,
0xa0a7aeb5,0xbcc3cad1,0xd8dfe6ed,0xf4fb0209,
0x10171e25,0x2c333a41,0x484f565d,0x646b7279
};

/**
 *	作用: S盒字节代换 
 */ 
static unsigned char SubByte(unsigned char num)
{
	unsigned char * ps = (unsigned char *) Sbox;			//获取数组指针 就可以一维数组访问 
	unsigned char retval = (unsigned char) (ps[num]);
	
	return retval;
}

/**
 *	作用: 参数ka 字节代换 + 线性运算 
 */ 
static unsigned long T(unsigned long ka)
{
	unsigned long bb = 0;
	unsigned long retval = 0;
	unsigned char a[4];
	unsigned char b[4];
	
	PUT_ULONG(ka, a, 0);				//ka放到数组a 
	for ( int i = 0; i < 4; i++ )
		b[i] = SubByte(a[i]);			//逐个字节代换到b 
	GET_ULONG(bb, b, 0); 
	retval = bb ^ ( ROTL(bb, 2) ^ ROTL(bb, 10) ^ ROTL(bb, 18) ^ ROTL(bb, 24) );	//最后线性运算 
	
	return retval;
}

/**
 *	参数 x0 x1 x2 x3: 原生数
 *  参数 rk: 密钥 
 */ 
static unsigned long F(unsigned long x0, unsigned long x1, unsigned long x2, unsigned long x3, unsigned long rk)
{
	return (x0 ^ T(x1 ^ x2 ^ x3 ^ rk));	
}

/**
 *	作用: 密钥扩展中的一轮 
 */ 
static unsigned long CalcRoundKey(unsigned long ka)
{
	unsigned long bb = 0;
	unsigned long retval = 0;
	unsigned char a[4];
	unsigned char b[4];
	
	PUT_ULONG(ka, a, 0);
	for ( int i = 0; i < 4; i++ )
		b[i] = SubByte(a[i]);
	GET_ULONG(bb, b, 0);
	retval = bb ^ (ROTL(bb, 13) ^ ROTL(bb, 23));
	
	return retval;	
} 

/**
 *	参数 SK: 密钥存放
 *	参数 key: 密钥 
 */  
static void SetKey(unsigned long SK[32], unsigned char key[16])
{
	unsigned long MK[4];
	unsigned long k[36];
	
	GET_ULONG(MK[0], key, 0);
	GET_ULONG(MK[1], key, 4);
	GET_ULONG(MK[2], key, 8);
	GET_ULONG(MK[3], key, 12);
	k[0] = MK[0] ^ FK[0];
	k[1] = MK[1] ^ FK[1];
	k[2] = MK[2] ^ FK[2];
	k[3] = MK[3] ^ FK[3];
	for ( int i = 0; i < 32; i++ )
	{
		k[i + 4] = k[i] ^ (CalcRoundKey(k[i + 1] ^ k[i + 2] ^ k[i + 3] ^ CK[i]));
		SK[i] = k[i + 4];
//		printf("0x%X, ", SK[i]);
	}
}

/**
 *	作用: 标准SM4一轮加密 
 *	参数 sk: 已初始化密钥
 *	参数 input: 明文字符串
 *	参数 output: 输入密文字符串 
 */
static void Round(unsigned long sk[32], unsigned char input[16], unsigned char output[16])
{
	unsigned long tmp[36] = { 0 };
	
	GET_ULONG(tmp[0], input, 0);
	GET_ULONG(tmp[1], input, 4);
	GET_ULONG(tmp[2], input, 8);
	GET_ULONG(tmp[3], input, 12);
	for ( int i = 0; i < 32; i++ )
		tmp[i + 4] = F(tmp[i], tmp[i + 1], tmp[i + 2], tmp[i + 3], sk[i]);
	PUT_ULONG(tmp[35], output, 0);
	PUT_ULONG(tmp[34], output, 4);
	PUT_ULONG(tmp[33], output, 8);
	PUT_ULONG(tmp[32], output, 12);
}

/**
 *	作用: 初始化加密密钥
 */ 
void SetKeyEnc(Context * ctx, unsigned char key[16])
{
	ctx->mode = ENC;
	SetKey(ctx->sk, key);
}

/**
 *	作用: 初始化解密密钥 
 */ 
void SetKeyDec(Context * ctx, unsigned char key[16])
{
	ctx->mode = DEC;
	SetKey(ctx->sk, key);
	for ( int i = 0; i < 16; i++ )
		SWAP(ctx->sk[i], ctx->sk[31 - i]);
}

/**
 *	参数 ctx: 结构体
 *	参数 mode: 解密或解密模式
 *	参数 len: input的长度
 *	参数 input: 明文字符串
 *	参数 output: 加密后字符串
 */
void CryptEBC(Context * ctx, int mode, int len, unsigned char * input, unsigned char * output)
{
	while ( len > 0)
	{
		Round(ctx->sk, input, output);
		
		input += 16;
		output += 16;
		len -= 16;
	}
}
 

//int main(void)
//{
//	unsigned long test[] = { 1, 2, 3, 4 };
//	unsigned long n = 0x01020304;
//	unsigned long data[4] = { 0 };
//	
//	n = GET_ULONG(n, test, 0);
//	printf("0x%X", n);
//	
//	puts("\n");
//	
//	PUT_ULONG(n, data, 0);
//	printf("0x%X, 0x%X, 0x%X, 0x%X", data[0], data[1], data[2], data[3]);
//	
//	puts("\n");
//	
//	printf("0x%X", SubByte(0xFF));
//	
//	return 0;
//}

main.c

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#include <stdio.h>
#include <string.h>
#include "SM4.h"

int main(void)
{
	unsigned char key[16] = 
	{
		0x01, 0x23, 0x45, 0x67, 0x89, 0xab, 0xcd, 0xef, 0xfe, 0xdc,
		0xba, 0x98, 0x76, 0x54, 0x32, 0x10
	};
	unsigned char input[16] = 			
	{
		0x01, 0x23, 0x45, 0x67, 0x89, 0xab, 0xcd, 0xef, 0xfe, 0xdc,
		0xba, 0x98, 0x76, 0x54, 0x32, 0x10
	};
	unsigned char output[16] =			
	{
		0xBE, 0x04, 0x06, 0x80, 0xC5, 0xAF, 0x76, 0x47, 0x9F, 0xCC, 
		0x40, 0x1F, 0xD8, 0xBF, 0x92, 0xEF
	};
	Context ctx;
	int i;
	
	SetKeyEnc(&ctx, key);
	CryptEBC(&ctx, 1, 16, input, output);
	for ( i = 0; i < 16; i++ )
		printf("0x%X, ", output[i]);
	
	puts("\n");
		
	SetKeyDec(&ctx, key);
	CryptEBC(&ctx, 0, 16, output, output);
	for ( i = 0; i < 16; i++ )
		printf("0x%X, ", output[i]);
	
	return 0;
}
DASCTF X SU
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About this Post

This post is written by P.Z, licensed under CC BY-NC 4.0.