Base64 encryption and decryption of files in MFC

Base64 encryption and decryption of files in MFC

/**

• Get file size
• @param path 文件路径
  */
  unsigned long myTools::get_file_size(const char *path)
  {
  unsigned long filesize = 0;
  FILE *fp;
  fp = fopen(path, “r+”);
  if(fp == NULL)
  return filesize;
  fseek(fp, 0L, SEEK_END);
  filesize = ftell(fp);
  fclose(fp);
  return filesize;
  }

/**

• Delete a single character
• @param str Enter the characters to be deleted in string c
  */
  void myTools::delchar( char *str, char c ) / /Delete specified characters
  { int count = 0; int i,j; for(i=j=0;str[i]! ='\0';i++) { if(str[i]!=c)//Determine whether there are characters that are the same as the characters to be deleted { str[j++]=str[i]; } if(str[i] ==’ ‘){ printf(“delete space!\n”); } if(str[i] == '\n '){ printf(“delete n !\n”); } } str [j]='\0';//End of string }
  
  
  
  
  
  
  
  
  
  
  
  
  
  
  
  
  

/**

• Base64 encryption of files

• @param filename 文件名 out_data 输出字符串
  */
  int myTools::file_base64(const char *filename, char *out_data)
  {
  unsigned long fileSize = get_file_size(filename);
  if (fileSize <= 0)
  return 0;

  fprintf(stderr,“the data size=%d\n”,fileSize);

  FILE* fp = fopen(filename, “rb”);
  char* inBuffer = new char[fileSize];
  ULONG uReaded = fread(inBuffer, 1, fileSize, fp);

  const BYTE* pbBinary = (const BYTE*)inBuffer;
  DWORD dwLen;
  CryptBinaryToStringA(pbBinary, fileSize, CRYPT_STRING_BASE64, NULL, & dwLen); //Convert binary sequence into string

  char* pCrypt1 = new char[dwLen];
  CryptBinaryToStringA(pbBinary, fileSize, CRYPT_STRING_BASE64, pCrypt1, &dwLen);//Convert binary sequence into string
  fclose(fp);

  delchar(pCrypt1, ‘\n’);
  delchar(pCrypt1, ‘\r’);
  strcpy(out_data, pCrypt1);
  if (inBuffer)
  {
  delete[] inBuffer;
  inBuffer = NULL;
  }
  if (pCrypt1)
  {
  delete[] pCrypt1;
  pCrypt1 = NULL;
  }
  return 0;
  }

/**

• Decode base64 data stream and write to file

• @param data 输入数据流 len 输入数据长度 url写入文件名
  */
  int myTools::base64_file(char *data,int len,char *url)
  {
  if(data==NULL)
  {
  return -1;
  }
  DWORD cbBinary;
  DWORD dwSkip;
  DWORD dwFlags;
  CryptStringToBinaryA(data, len+1, CRYPT_STRING_BASE64, NULL, &cbBinary, &dwSkip, &dwFlags);

  BYTE* outBuffer = new BYTE[cbBinary];
  CryptStringToBinaryA(data, len+1, CRYPT_STRING_BASE64, outBuffer, &cbBinary, &dwSkip, &dwFlags);

  FILE* fp = fopen(url, “wb”);
  ULONG uWrite = fwrite(outBuffer, 1, cbBinary, fp);

  fclose(fp);
  if (outBuffer)
  {
  delete[] outBuffer;
  outBuffer = NULL;
  }
  return 0;
  }