Question

Is there a way to store data on a USB file in a way that the OS cannot read it with the standard methods? I was thinking maybe with an uncommon filesystem, but then I ‘d probably have to implement the IO myself, which sounds like a huge work.
Another idea would be to access the disk sectors in a low level way and store data in an incompatible way? But I do not know where to begin.
For the record, I am using VB.NET.

Thank you,

John

EDIT: Regarding the VALID security concerns you have raised: I agree, but please assume that, all I need to do for the scope of my project, is to simply hinder the average and slightly advanced user. NOT the expert. Thank you for raising the security issue, but it can be safely ignored on this particular case.

Answer 1

Essentially what you are asking for is almost a rootkit. I don’t think this is a path you want to go down.

You could repartition the drive so that it has a 2nd partition you could do raw I/O to, but that doesn’t provide any real security. (and it would make your software unnecessarily complex.) So, why not simply mark them readonly + hidden + system and add your real security by other means?

You will have considerable security problems trying to do this, as others have already pointed out. Things to consider:

• Replay attacks (someone copying the drive byte-for-byte – which is very easy to do by the way)
• Someone finding the file and modifying it (it should be validated using a third-party digital signature known only to your program – and your program must somehow secure its private key)