wencrypt.h

汇编内核的md5算法.使用方法：一种方法是使用原代码包中的make.bat

/***********************************************************
 *                                                         *
 *         WEncrypt class for file encryption              *
 *                                                         *
 *                ### Wael Tahon ###                       *
 *                                                         *
 ***********************************************************
 * usage:                                                  *
 *********                                                 *
 *                                                         *
 * WEncryption *obj;                                       *
 * obj = new WEncryption("srcfile","newfile","password");  *
 * obj->EncryptFile();                                     *
 *                                                         *
 *   Or                                                    *
 *                                                         *
 * obj->DecryptFile();                                     *
 * delete obj;                                             *
 *                                                         *
 ***********************************************************
 * Note:-                                                  *
 *********                                                 *
 *                                                         *
 * Do not try to edit any encrypted files.                 *
 *                                                         *
 *    if(you_lose_one_byte)                                *
 *         your_file = destroyed;                          *
 *                                                         *
 ***********************************************************
 *                                                         *
 * Please send me your remarks about this class.           *
 *                                                         *
 * E-Mail:      [e-mail]                       *
 * Web page:    wael_tahon.tripod.com                      *
 * Phone:       [phone]                                *
 *                                                         *
 ***********************************************************/

#ifndef _WENCRYPT_H_
#define _WENCRYPT_H_

/*************************************************/
/*               Return values                   */
/*************************************************/

#define NO_ERRORS_DONE   0   //No errors.
#define ERROR_SRC_FILE   1   //Can't open the source file.
#define ERROR_DST_FILE   2   //Can't create the new file.
#define ERROR_CANT_ENC   3   //Can't encrypt the file (must be normal file).
#define ERROR_CANT_DEC   4   //Can't decrypt the file (must be encrypted file).

/*************************************************/
#define ENCRYPTED_FILE  5   //The file is an encrypted file.
#define NORMAL_FILE     6   //The file is a normal file.
/*************************************************/
#include<stdio.h>
#include<string.h>
/*************************************************/
class WEncryption{           //Declaring the class.

/***********/
  private:                   //Private members.
/***********/

  char *SrcFile;             //The source file name.
  char *OutFile;             //The new file name.
  char password[64];         //The encryption key 64 bytes max.

/*************************************************/
/*               Check if encrypted              */
/*************************************************/
  int  CheckIfEncrypted(char *file)
  {
    int m[19];
    FILE *h = fopen(file, "rb");
    for(int d=0; d<19; d++)
       m[d] = fgetc(h);
    fclose(h);
    if(m[0]==3&&m[1]==2&&m[2]==3&&m[3]==4&&m[4]==0&&m[5]==2&&
       m[6]==3&&m[7]==2&&m[8]==3&&m[9]==4&&m[10]==0&&m[11]==2&&
       m[12]==3&&m[13]==5&&m[14]==7&&m[15]==0&&m[16]==9&&m[17]==5&&m[18]==0)
       return ENCRYPTED_FILE;
    else
       return NORMAL_FILE;
  };
/*************************************************/
/*       Mark the file by 19 bytes mark          */
/*************************************************/
      int MarkTheFile(FILE *f)
      {
        int m[]={3,2,3,4,0,2,3,2,3,4,0,2,3,5,7,0,9,5,0};  // My phone numbers !!
        for(int d=0; d<19; d++)
           fputc(m[d], f);
        return 0;
      };
/*************************************************/
/*              Get the file size                */
/*************************************************/
      int GetFileSize(char *ff)
      {
       FILE *z = fopen(ff, "r");
       long int cur;
       fseek(z, 0L, SEEK_END);
       cur = ftell(z);
       fclose(z);
       FileSize = cur;
       return 0;
      };
/*************************************************/

/**********/
  public:                    //Public members.
/**********/
  long int FileSize;         //The file size.
  long int CurPosition;      //The current position inside the file.

/*************************************************/
/*                Constructor                    */
/*************************************************/
  WEncryption(char *src,char *dst,char pass[64])
  {
   FileSize=CurPosition=0;
   SrcFile=src;
   OutFile=dst;
   strcpy(password,pass);
  };

/*************************************************/
/*                 Destructor                    */
/*************************************************/
      ~WEncryption()
      {
      };
/*************************************************/
/*                File encryption                */
/*************************************************/
      int EncryptFile()
      {
        FILE *r, *w;
        int blah=0;
        int g=0;
        unsigned int ch;
        GetFileSize(SrcFile);

          if(CheckIfEncrypted(SrcFile) != NORMAL_FILE)
          {
            return ERROR_CANT_ENC;
          }

          if((r = fopen(SrcFile, "rb")) == NULL)
          {
            return ERROR_SRC_FILE;
          }

          if((w = fopen(OutFile, "wb")) == NULL)
          {
            return ERROR_DST_FILE;
          }

        MarkTheFile(w);      // Mark the file.
        CurPosition=0;
/***************************************/
/*        Encryption algorithm         */
/***************************************/
          for(long int v=0;;v++)
          {
               for(g=0; g<64; g++)
               {
                    CurPosition++;
                       if((ch=fgetc(r))==EOF)
                        {
                           blah = 1;
                           break;
                        }
                       if((ch%2)==0)
                        {
                           ch+=1;
                        }
                       else
                        {
                           ch+=3;
                        }
                     ch =(~ch^(int)password[g])^(v^~g);
                     fputc(ch, w);
               }
             if(blah == 1)
              {
                 break;
              }
          }
/***************************************/
        fclose(r);
        fclose(w);
        return NO_ERRORS_DONE;
      };
/*************************************************/
/*                File decryption                */
/*************************************************/
      int DecryptFile()
      {
         FILE *r, *w;
         int blah = 0;
         int g = 0;
         unsigned int ch;
         GetFileSize(SrcFile);

           if( CheckIfEncrypted(SrcFile) != ENCRYPTED_FILE )
           {
             return ERROR_CANT_DEC;
           }

           if((r = fopen( SrcFile, "rb")) == NULL)
           {
             return ERROR_SRC_FILE;
           }

           if((w = fopen( OutFile, "wb")) == NULL)
           {
             return ERROR_DST_FILE;
           }

      char *zzz = "";
      fread(zzz, 19, 1, r); // Skip 19 bytes from the file.
      CurPosition=0;
/***************************************/
/*       Decryption algorithm          */
/***************************************/
           for(long int v=0;;v++)
           {
                for(g=0; g<64; g++)
                {
                     CurPosition++;
                      if((ch = fgetc(r)) == EOF)
                       {
                           blah = 1;
                           break;
                       }
                      ch = ~((ch^(v^~g))^(int)password[g]);
                       if((ch%2)==0)
                        {
                           ch-=3;
                        }
                       else
                        {
                           ch-=1;
                        }
                     fputc(ch, w);
                }
                if(blah == 1)
                 {
                     break;
                 }
          }
/***************************************/
         fclose(r);
         fclose(w);
         return NO_ERRORS_DONE;
      };
/*************************************************/
};
#endif