文本动态随机加密

 

 

#include <Windows.h>#include <atlstr.h>//可以用 cstring了 #include <stdio.h>//#pragma comment(lib,"kernel32.lib")//#pragma comment(lib,"user32.lib")//#pragma comment(linker, "/SUBSYSTEM:windows")//#pragma comment(linker, "/ENTRY:main")#ifdef _UNICODE#defineTextEncrypt TextEncryptW#defineTextDecryption TextDecryptionW#else#defineTextEncrypt TextEncryptA#defineTextDecryption TextDecryptionA#endifconst CHAR m_szWord[]="abcdefghijklmnopqrstuvwxyzABCDEFGHIJKLMNOPQRSTUVWXYZ0123456789";const int m_cchWordLen=strlen(m_szWord);int MyRand(int Min,int Max)//取随机数 使用前请先调用 srand(time(NULL)); {int bychu=(int)rand();int chu=Max-Min+1;int shang=bychu/chu;int dret=bychu-shang*chu+Min;return dret;}LPSTR TextEncryptA(LPCSTR szText,LPCSTR szKey,int cbKeyLen)//加密A 密文长度为原文长度的4倍 (返回结果 调用者 free){if (cbKeyLen==0){cbKeyLen=strlen(szKey);}int nTextLen=strlen(szText);int j=0,k=0;srand(GetTickCount());int nCurPos=0;printf("keylen:%d textlen:%d/n",cbKeyLen,nTextLen);LPSTR szRetBuff=(LPSTR)malloc(nTextLen*4+1);//调用者 freefor (int i=0;i<nTextLen;i++){if (j>=m_cchWordLen)//防止数据溢出j=0;if (k>=cbKeyLen)//防止数据溢出k=0;int nRandKey=MyRand(1,2500);//随机密匙int nShang=nRandKey/m_cchWordLen;//下面两句把随机密钥分解成两个数据，一个是商，一个是余，将商乘上码表长度加上余数就是随机密匙int nYu=nRandKey%m_cchWordLen;szRetBuff[nCurPos++]=m_szWord[nShang];szRetBuff[nCurPos++]=m_szWord[nYu];//临时字节 ＝ 位异或 (数据 [计数1], 码表 [计数2], 密码字节集 [计数3], 随机密匙) ' 把原数据内的对应字节这些值组合起来，形成一个新的数据int nTmp=(byte)szText[i]^m_szWord[j]^(byte)szKey[k]^nRandKey;nTmp^=35;nShang=nTmp/m_cchWordLen;//下面两句把商数分解成两个数据，一个是商，一个是余，将商乘上码表长度加上余数就是随机密匙nYu=nTmp%m_cchWordLen;szRetBuff[nCurPos++]=m_szWord[nShang];szRetBuff[nCurPos++]=m_szWord[nYu];k++;j++;}szRetBuff[nCurPos]='/0';return szRetBuff;}LPWSTR TextEncryptW(LPCWSTR szText,LPCWSTR szKey)//宽字符版 密文长度为原文长度的4倍 (返回结果必须 调用者 free){if (szText==NULL ||szKey==NULL){return NULL;}int nNeed=WideCharToMultiByte(CP_ACP,0,szText,-1,NULL,0,NULL,NULL);//待加密的转换char *const szAText=(char *const )malloc(nNeed);WideCharToMultiByte(CP_ACP,0,szText,-1,szAText,nNeed,NULL,NULL);//待加密的转换char *const szARetBuff=(char *const )malloc(nNeed*4);//返回结果nNeed=WideCharToMultiByte(CP_ACP,0,szKey,-1,NULL,0,NULL,NULL);char *const szAKey=(char*const)malloc(nNeed);WideCharToMultiByte(CP_ACP,0,szKey,-1,szAKey,nNeed,NULL,NULL); LPSTR szARet=TextEncryptA(szAText,szAKey,0);//调用ansi版的nNeed=MultiByteToWideChar(CP_ACP,0,szARet,-1,NULL,0);WCHAR *szRetBuff=(WCHAR*)malloc(nNeed*sizeof(WCHAR));MultiByteToWideChar(CP_ACP,0,szARet,-1,szRetBuff,nNeed);free(szARet);//调用者free free(szAText); free(szARetBuff); free(szAKey);return szRetBuff;}//abcdefghijklmnopqrstuvwxyzABCDEFGHIJKLMNOPQRSTUVWXYZ0123456789inline int GetPosByChar(char cf){if (cf>='a' &&cf<='z'){return cf-'a';}if (cf>='A' &&cf<='Z'){return 26+cf-'A';}if (cf>='0'&& cf<='9'){return 26+26+cf-'0';}return -1;}LPSTR TextDecryptionA(LPCSTR szText,LPCSTR szKey,int cbKeyLen)//返回结果由调用者free(){if (szText==NULL || szKey==NULL){return NULL;}if (cbKeyLen==0){cbKeyLen=strlen(szKey);}int nTextLen=strlen(szText);if (nTextLen%4!=0){return NULL;}int j=0,k=0;srand(GetTickCount());int nCurPos=0;printf("keylen:%d textlen:%d/n",cbKeyLen,nTextLen);LPSTR szRetBuff=(LPSTR)malloc(nTextLen/4+1);//调用者 freefor (int i=0;i<nTextLen;i+=4){if (j>=m_cchWordLen)j=0;if (k>=cbKeyLen)k=0;//某个字节在码表中的位置就是我们要在这个位置上保存的整数。这里我们通过取出商和余就能求出那个随机密匙int nShang=GetPosByChar(szText[i]);int nYu=GetPosByChar(szText[i+1]);if (nShang==-1 ||nYu==-1){free(szRetBuff);return NULL;}int nRandKey=nShang*m_cchWordLen+nYu;//被除数=除数×商+余数，小学的知识 被除数就是我们保存的数据——随机密匙nShang=GetPosByChar(szText[i+2]);nYu=GetPosByChar(szText[i+3]);if (nShang==-1 ||nYu==-1){free(szRetBuff);return NULL;}int nTmp=nShang*m_cchWordLen+nYu;nTmp^=35;nTmp=nTmp^m_szWord[j]^szKey[k]^nRandKey;szRetBuff[nCurPos++]=(char)nTmp;j++;k++;}szRetBuff[nCurPos]='/0';return szRetBuff;}LPWSTR TextDecryptionW(LPCWSTR szText,LPCWSTR szKey)//w版本 返回结果必须调用者free(){if (szText==NULL ||szKey==NULL){return NULL;}int nNeed=WideCharToMultiByte(CP_ACP,0,szText,-1,NULL,0,NULL,NULL);char *const szAText=(char*const)malloc(nNeed);WideCharToMultiByte(CP_ACP,0,szText,-1,szAText,nNeed,NULL,NULL);nNeed=WideCharToMultiByte(CP_ACP,0,szKey,-1,NULL,0,NULL,NULL);char *const szAKey=(char*const)malloc(nNeed);WideCharToMultiByte(CP_ACP,0,szKey,-1,szAKey,nNeed,NULL,NULL);char *szRet=TextDecryptionA(szAText,szAKey,0);free(szAText);free(szAKey);if (szRet==NULL){return NULL;}nNeed=MultiByteToWideChar(CP_ACP,0,szRet,-1,NULL,NULL);LPWSTR szRetBuff=(LPWSTR)malloc(nNeed*sizeof(WCHAR));MultiByteToWideChar(CP_ACP,0,szRet,-1,szRetBuff,nNeed);free(szRet);//调用者释放return szRetBuff;}int main(){//参考 http://bbs.eyuyan.com/read.php?tid=247112char *szRet=TextEncryptA("老大爷你好呀","ss你abcd",0);printf("加密结果:/n%s/n",szRet);char *szDecry=TextDecryptionA(szRet,"ss你abcd",0);printf("解密结果:/n%s/n",szDecry);free(szRet);free(szDecry);//不能忘记 free返回结果return 0;}