File Hidden Research And Implementation Based On The FAT32 File System

With the development of social and technological, the application of computer becomes more and more universal. To protect the confidential data in the computer from being stolen and protect personal privacy information in the computer from being peeped, people make a lot of efforts in the research of file hidden ways.Because the series of Windows OS (Operating System) almost occupy the whole market of PC OS, so, mostly, people in the research of file hidden choose the Windows OS as the platform. There are some types of implementation: implementation of modifying registry, implementation of making use of recycled characteristic, implementation of hooking OS API (Application Programming Interface) function, implementation of encrypting file, implementation of modifying the file system structure. With the comparison of hidden strength, the way by modifying registry and the way by making use of recycled characteristic are worse, and the way by hooking OS API is better than the two previously mentioned ways, but it is only available in current OS. The way by encrypting files is inconvenient in use, and it is very slow to process big files.The way of file hidden based on FAT32 (File Allocation Table 32) File System, which hides file by adding the volume attribute to the file to be hidden, can hide files in FAT32 File System with any file format. The time it spent is not affected by the file size. And it has permanent effect, won't become invalid with the change of OS. But it also has shortage that its data can be gotten by getting its directory entry with the way of directly reading the data of disk sector. On the basis of this way, an improved way was proposed, which improves performance by changing the first cluster no. of the file to be hidden, strengthen the hidden strength with inheriting the advantages of the previous way.