It's apparently pretty common for people to create virtual Truecrypt volumes and stick them on Dropbox, as a sort of poor-hacker's encrypted Dropbox.
People do that? encfs/ecryptfs sounds like a much better fit for that use case. Encryption is per file and you can even disable the filename encryption if you want to still be able to navigate your files using their interface. Are there no good similar solutions for Windows/OSX?
encfs uses the same questionable encryption techniques that motivated the creation of XTS in the first place. It's structured almost like full-disk encryption at the file level. I think the same's true of ecryptfs.
EncFS is a FUSE filesystem. There is no reason for it to use sector-level encryption. It's format-aware. It can do fully randomized encryption and provide strong authentication. However, someone involved in EncFS did propose switching to XTS. Which is actually what prompted me to write this article.
Oh. Oh dear. The reason that EncFS were considering switching to XTS is because their last security audit suggested it[1], probably with good reason. Remember that many applications also expect fast sector-level random read and write access to files; add in the potential for power-failure-related data corruption and missing writes, and you can't really do much better than XTS. (At least not whilst relying on a normal filesystem as your backend; ZFS can probably do more.)
No, this isn't true at all. If you don't have the physical disk geometry problem, you shouldn't be using XTS. In fact, the whole article is about exactly this point.
In particular: you do not need XTS to get "fast random read and write access".
Taylor's a smart guy. I'm pretty sure he's wrong about this (although maybe he knows something applicable about EncFS that I don't know). If I thought that there was no way any smart person could make the mistake of applying XTS somewhere it didn't belong, there'd be no point to writing the article. :)
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People do that? encfs/ecryptfs sounds like a much better fit for that use case. Encryption is per file and you can even disable the filename encryption if you want to still be able to navigate your files using their interface. Are there no good similar solutions for Windows/OSX?
encfs uses the same questionable encryption techniques that motivated the creation of XTS in the first place. It's structured almost like full-disk encryption at the file level. I think the same's true of ecryptfs.
EncFS is a FUSE filesystem. There is no reason for it to use sector-level encryption. It's format-aware. It can do fully randomized encryption and provide strong authentication. However, someone involved in EncFS did propose switching to XTS. Which is actually what prompted me to write this article.
Oh. Oh dear. The reason that EncFS were considering switching to XTS is because their last security audit suggested it[1], probably with good reason. Remember that many applications also expect fast sector-level random read and write access to files; add in the potential for power-failure-related data corruption and missing writes, and you can't really do much better than XTS. (At least not whilst relying on a normal filesystem as your backend; ZFS can probably do more.)
[1] https://defuse.ca/audits/encfs.htm
No, this isn't true at all. If you don't have the physical disk geometry problem, you shouldn't be using XTS. In fact, the whole article is about exactly this point.
In particular: you do not need XTS to get "fast random read and write access".
Taylor's a smart guy. I'm pretty sure he's wrong about this (although maybe he knows something applicable about EncFS that I don't know). If I thought that there was no way any smart person could make the mistake of applying XTS somewhere it didn't belong, there'd be no point to writing the article. :)