binary data file tampering

[trbo_usr]

I would like opinions about how tamper-resistant I can claim to be when I save a binary file format from my (executable) application.  This format is a pretty complex cluster of clusters, each of the sub-clusters containing various arrays, text, boolean, numeric values, etc.  If someone has ONLY this data file, and general Labview knowledge plus a general sense of what to look for in these files, can he/she determine the exact file structure and selectively modify the data values with some kind of home-made editor?  If so, what would be a good way to prevent this tampering?

[SteelStonehenge]

One of the truisms about security is that you can never make it bullet-proof, but you can make it inconvenient.  You should strive to make it inconvenient, and your data structure probabl qualifies as that.  Of course, anyone with a hex editor can tweak it, whether they KNOW what they're tweaking or not.  I'm not sure what your end goal is....if it's absolute security you're after, you might have to go to data encryption.  Are you trying to HIDE the data, or just prevent manipulation?  For the latter, you can usually achieve that with proper use of file permissions.

We need a bit more information to help you much.

Eric

[trbo_usr]

Thanks...I am looking at the potential for someone to intentionally change a specific value in the file so that it opens up properly, but shows a different number than when it was saved.  Random tampering or file corruption are not the concern.  I imagined potentially that there was a LabView tool that let anyone inspect any binary file and determine its structure, then edit the content knowing what it was they were editing.  Not the case?

[SteelStonehenge]

Well, here's an idea.  Why don't you post a sample of the data on here, and see if anyone on here can "crack" it.  We have a lot of smart people on here, and if someone here can't do it...you're probably pretty safe.  🙂

eric

[BillMe]

You might want to leverage against the LabVIEW 8.2 MD5 digital signature VI. Run that on your file and then store the digital signature somewhere secure. We put it in a configuration managed document that our QA people use to make sure our files haven't changed "inadvertently".