Thread: cryptsetup: encrypted filesystem on your N900
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Joorin is offline Joorin
2010-05-17 , 15:10
Posts: 726 | Thanked: 345 times | Joined on Apr 2010 @ Sweden
#19
Originally Posted by soeiro View Post
First, there are situations where just knowing that something is there is equally as good (or as bad) as knowing what is there.
So, you're thinking about "plausible deniability"? If you get pulled over in customs and have your phone device searched, you want to be able to deny that there's anything on it without them being able to find out?

I understand the need in that situation, but it's not related to actually finding out what's stored on the device.

Second, by analyzing the exact size it is possible to help to infer what kind of information is there.
Eh? File systems typically work in blocks. Within blocks you get fragmentation, half a block per file on average. So, by looking at the amount of blocks that are used (if that's something that you can infer) would give you an accuracy of half a block.

I'd say that it's very hard to find "the exact size" without actually reading the file system which requires decryption.

Third, it is a lot easier to perform cryptanalysis when the exact size is known.
See above.