C语言实现SM4加解密方式
作者:OctopusMonster
这篇文章主要介绍了C语言实现SM4加解密方式,具有很好的参考价值,希望对大家有所帮助。如有错误或未考虑完全的地方,望不吝赐教
C语言实现SM4加解密
简介:
sm4也是一种对称加密算法,使用16字节秘钥加解密16字节数据。
先生成32个32位子秘钥,数据再配合秘钥迭代计算数据32次,取最后四次生成的32位数据,倒序组合成128位结果。
使用到3张表,系统参数表,固定参数表,和sbox表。
128位秘钥拆分成4段32位,分别异或4个系统参数得到k1到k4,k5到k6分别依赖前4组秘钥使用固定算法所得..... 过程可根据代码了解,流程比较简单。
tables.h
#ifndef _SM4_H_ #define _SM4_H_ #include <stdio.h> #include <string.h> const unsigned long TBL_SYS_PARAMS[4] = { 0xa3b1bac6, 0x56aa3350, 0x677d9197, 0xb27022dc }; const unsigned long TBL_FIX_PARAMS[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 }; const unsigned char TBL_SBOX[256] = { 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 }; #endif
sm4_tool.c
#include "tables.h" void four_uCh2uLong(unsigned char *in , unsigned long *out); void uLong2four_uCh(unsigned long in , unsigned char *out); unsigned long move(unsigned long data , int length); unsigned long func_key(unsigned long input); unsigned long func_data(unsigned long input); int proc_enc_dec(char *type , unsigned char *key , unsigned char *input , unsigned char *output); void print_hex(unsigned char *data , int len); int hex_str2bytes(unsigned char *in , unsigned char *out , int *outLen); //4字节无符号数组转无符号long型 void four_uCh2uLong(unsigned char *in , unsigned long *out) { int i = 0; *out = 0; for(i = 0 ; i < 4 ; i++) *out = ((unsigned long)in[i] << (24-i*8)) ^ *out; } //无符号long型转4字节无符号数组 void uLong2four_uCh(unsigned long in , unsigned char *out) { int i = 0; //从32位unsigned long的高位开始取 for(i = 0 ; i < 4 ; i++) *(out+i) = (unsigned char )(in >> (24-i*8)); } //左移,保留丢弃位放置尾部 unsigned long move(unsigned long data , int length) { unsigned long result = 0; result = (data << length) ^ (data >> (32-length)); return result; } //秘钥处理函数 unsigned long func_key(unsigned long input) { int i = 0; unsigned long ulTmp = 0; unsigned char ucIndexList[4] = {0}; unsigned char ucSboxValueList[4] = {0}; uLong2four_uCh(input , ucIndexList); for(i = 0 ; i < 4 ; i++) { ucSboxValueList[i] = TBL_SBOX[ucIndexList[i]]; } four_uCh2uLong(ucSboxValueList , &ulTmp); ulTmp = ulTmp ^ move(ulTmp , 13) ^ move(ulTmp , 23); return ulTmp; } //加解密数据处理函数 unsigned long func_data(unsigned long input) { int i = 0; unsigned long ulTmp = 0; unsigned char ucIndexList[4] = {0}; unsigned char ucSboxValueList[4] = {0}; uLong2four_uCh(input , ucIndexList); for(i = 0 ; i < 4 ; i++) { ucSboxValueList[i] = TBL_SBOX[ucIndexList[i]]; } four_uCh2uLong(ucSboxValueList , &ulTmp); ulTmp = ulTmp ^ move(ulTmp , 2) ^ move(ulTmp , 10) ^ move(ulTmp , 18) ^ move(ulTmp , 24); return ulTmp; } //加解密函数 int proc_enc_dec(char *type , unsigned char *key , unsigned char *input , unsigned char *output) { int i = 0; unsigned long ulKeyTmpList[4] = {0}; unsigned long ulKeyList[36] = {0}; unsigned long ulDataList[36] = {0}; /*开始生成子秘钥*/ four_uCh2uLong(key , &(ulKeyTmpList[0])); four_uCh2uLong(key+4 , &(ulKeyTmpList[1])); four_uCh2uLong(key+8 , &(ulKeyTmpList[2])); four_uCh2uLong(key+12 , &(ulKeyTmpList[3])); ulKeyList[0] = ulKeyTmpList[0] ^ TBL_SYS_PARAMS[0]; ulKeyList[1] = ulKeyTmpList[1] ^ TBL_SYS_PARAMS[1]; ulKeyList[2] = ulKeyTmpList[2] ^ TBL_SYS_PARAMS[2]; ulKeyList[3] = ulKeyTmpList[3] ^ TBL_SYS_PARAMS[3]; for(i = 0 ; i < 32 ; i++) { //5-36为32个子秘钥 ulKeyList[i+4] = ulKeyList[i] ^ func_key(ulKeyList[i+1] ^ ulKeyList[i+2] ^ ulKeyList[i+3] ^ TBL_FIX_PARAMS[i]); } /*生成32轮32位长子秘钥结束*/ /*开始处理加解密数据*/ four_uCh2uLong(input , &(ulDataList[0])); four_uCh2uLong(input+4 , &(ulDataList[1])); four_uCh2uLong(input+8 , &(ulDataList[2])); four_uCh2uLong(input+12 , &(ulDataList[3])); if(strcmp(type , "1") == 0) { //加密 for(i = 0 ; i < 32 ; i++) { ulDataList[i+4] = ulDataList[i] ^ func_data(ulDataList[i+1] ^ ulDataList[i+2] ^ ulDataList[i+3] ^ ulKeyList[i+4]); } } else if(strcmp(type , "2") == 0) { //解密 for(i = 0 ; i < 32 ; i++) { ulDataList[i+4] = ulDataList[i] ^ func_data(ulDataList[i+1] ^ ulDataList[i+2] ^ ulDataList[i+3] ^ ulKeyList[35-i]); } } uLong2four_uCh(ulDataList[35] , output); uLong2four_uCh(ulDataList[34] , output+4); uLong2four_uCh(ulDataList[33] , output+8); uLong2four_uCh(ulDataList[32] , output+12); return 0; } //无符号字符数组转16进制打印 void print_hex(unsigned char *data , int len) { int i = 0; char alTmp[16] = {'0','1','2','3','4','5','6','7','8','9','a','b','c','d','e','f'}; for(i = 0 ; i < len ; i++) { printf("%c" , alTmp[data[i]/16]); printf("%c" , alTmp[data[i]%16]); // putchar(' '); } putchar('\n'); } //16进制数组转无符号字符数组 int hex_str2bytes(unsigned char *in , unsigned char *out , int *outLen) { int i = 0 , j = 0; int num = 0; int tmp = 0; for (i = 0 ; i < strlen((char *)in) ; i++) { if(in[i] < 58 && in[i] > 47) //0-9 tmp = in[i]-48; else if(in[i] < 71 && in[i] > 64) //A-F tmp = 10+in[i]-65; else if(in[i] < 103 && in[i] > 96) //a-f tmp = 10+in[i]-97; else { printf("Invalid arg!\n"); return -1; } if(i%2 == 0) num = tmp*16; else { num += tmp; out[j++] = num; } } *outLen = j; return 0; } int main(int argc , char **argv) { unsigned char alResult[16] = {0}; unsigned char alKey[16] = {0}; int ilKeyLen = 0; unsigned char alData[16] = {0}; int ilDataLen = 0; if(argc != 4 || strlen(argv[2]) != 32 || strlen(argv[3]) != 32 || (strcmp(argv[1] , "1") != 0 && strcmp(argv[1] , "2") != 0) ) { printf("Usage: ./sm4_tool [1/2] hex32_key hex32_data\n1:encrypt , 2:decrypt\n"); return -1; } if(hex_str2bytes((unsigned char *)argv[2] , alKey , &ilKeyLen)) return -1; if(hex_str2bytes((unsigned char *)argv[3] , alData, &ilDataLen)) return -1; proc_enc_dec(argv[1] , alKey , alData , alResult); print_hex(alResult , 16); return 0; }
Makefile:
TARGET = sm4_tool DEPEND = sm4_tool.o CC = gcc -g -Wall RM = rm -f .c.o : $(CC) -c $^ -o $@ $(TARGET) : $(DEPEND) $(CC) $^ -o $@ .PHONY : clean clean : $(RM) $(TARGET) *.o
这里main函数参数只针对16字节秘钥和16字节数据测试用。
加密:./sm4_tool 1 0123456789abcdeffedcba9876543210 0123456789abcdeffedcba9876543210
结果:
681edf34d206965e86b3e94f536e4246
解密:./sm4_tool 2 0123456789abcdeffedcba9876543210 681edf34d206965e86b3e94f536e4246
结果:
0123456789abcdeffedcba9876543210
C语言文件加解密
#include <stdio.h> #include <stdlib.h> #define N 30 //文件名字的长度 /**************************************************************************/ //函数功能:解密字符串 //参数: // src_file_text:要解密的字符串。 length:字符串的长度 // password: 解密密码 //返回值: 解密后的字符串的首地址 /**************************************************************************/ char * file_text_decrypt(char * src_file_text,unsigned long int length,unsigned int password) { char * file_text=NULL; char * result_text=NULL; unsigned long int i; result_text=file_text=src_file_text; for(i=0;i<length;i++) { *file_text++ = (*src_file_text++)-password; } return result_text; } /**************************************************************************/ //函数功能:将字符串保存到目的文件中 //参数: // text:要保存的字符串首地址 。 file_name :目的文件的名字 // length:字符串的长度 /**************************************************************************/ void save_file(char* text,unsigned long int length,char * file_name) { FILE *dest_fp; dest_fp=fopen(file_name,"wb+"); if(dest_fp==NULL) { printf("open %s faild\n",file_name); } if(fwrite(text,length,1,dest_fp)<=0) { printf("write %s error\n",file_name); } else { printf("save sucess\n"); } fclose(dest_fp); } /**************************************************************************/ //函数功能:加密字符串 //参数: // src_file_text:要加密的字符串。 length:字符串的长度 // password: 加密密码 // 返回值: 加密后的字符串的首地址 /**************************************************************************/ char * file_text_encrypt(char * src_file_text,unsigned long int length,unsigned int password) { char * file_text=NULL; char * result_text=NULL; unsigned int i; result_text=file_text=src_file_text; for(i=0;i<length;i++) { *file_text++ = (*src_file_text++)+password; } return result_text; } /**************************************************************************/ // 函数功能:读出文件内容 // 参数: // file_length:整型指针,此地址中保存文件字节数。 // src_file_name:文件名字,从此文件中读取内容。 // 返回值:读出字符串的首地址 /**************************************************************************/ char * read_src_file(unsigned long int *file_length,char *src_file_name) { unsigned long int FILE_SIZE=0; char *src_file_text=NULL; FILE *fp; fp=fopen(src_file_name,"rb"); if(fp==NULL) { printf("open %s faild\n",src_file_name); return 0; } fseek(fp,0,SEEK_END); FILE_SIZE=ftell(fp); *file_length=FILE_SIZE; rewind(fp); src_file_text=(char *)malloc(FILE_SIZE); if(fread(src_file_text,FILE_SIZE,1,fp)==0) { printf("read from src_file faild\n"); return NULL; } fclose(fp);// 关闭文件 return src_file_text ; } /**************************************************************************/ //函数功能:获取 目的文件和源文件的名字 //参数: // src_file_name:源文件名字。 // dest_file_name:目的文件的名字 /**************************************************************************/ void get_file_name(char * dest_file_name,char * src_file_name) { printf("请输入你的原文件名称(%d个字符):",N); gets(src_file_name); printf("请输入你的目的文件名称(%d个字符):",N); gets(dest_file_name); } /**************************************************************************/ // // 函数功能:打印帮助信息 // /**************************************************************************/ void print_help() { printf("********1:加密文件***********\n"); printf("********2:解密文件***********\n"); printf("********3:退出程序***********\n"); } int main() { char src_file_name[N]=""; //源文件的名字 char dest_file_name[N]=""; //目标文件的名字 char *src_file_text=NULL; //指向malloc的空间,其存入的是 源文件的内容 unsigned long int file_length=0; //保存 源文件的长度 unsigned int password=0; int menu=0; while(1) { print_help(); scanf("%d",&menu); getchar(); //提取输入缓存区中的'\n' switch(menu) { case 1 : { get_file_name(dest_file_name,src_file_name); // 获取原文件和目的文件名 src_file_text=read_src_file(&file_length,src_file_name);// 从源文件中读取数据 printf("please input your unsigned int passworld:"); scanf("%d",&password);// 输入密码 必须是无符号整型的 getchar(); src_file_text=file_text_encrypt(src_file_text,file_length,password);// 给字符串加密返回加密后的字符串的首地址 save_file(src_file_text,file_length,dest_file_name);// 将字符串保存到目的文件中 if(src_file_text!=NULL) free(src_file_text);//回收资源 break; } case 2: { get_file_name(dest_file_name,src_file_name); // 获取原文件和目的文件名 src_file_text=read_src_file(&file_length,src_file_name);// 从源文件中读取数据 printf("please input your passworld:"); scanf("%d",&password); // 获取密码 getchar(); src_file_text=file_text_decrypt(src_file_text,file_length,password);// 解密字符串,返回解密后的字符串的首地址 save_file(src_file_text,file_length,dest_file_name);// 将解密后的字符串保存到目的文件中 if(src_file_text!=NULL) free(src_file_text);//回收资源 break; } case 3: { return 0; // 退出 程序 } default : { printf("请输入一个正确的选项 \n"); } } } return 0; }
总结
以上为个人经验,希望能给大家一个参考,也希望大家多多支持脚本之家。