Em 17-04-2014 08:05, alexander taylor escreveu: > thanks for the reply! i am trying to keep the keys safe in the > scenario whereby an attacker steals someone's computer, takes out the > hard drive, mounts it in another machine and bypasses access rights > specified by the filesystem. > If this is what you're trying to accomplish, you're better off instructing your friends and colleagues to using full disk encryption. On windows there is bitlocker, which I advise against but is on the system right after installation, and there truecrypt, which is better. On mac there is filevault, but it does encryption on file level rather than disk level. On linux there is dm-crypt, luks, ecryptfs, and probably some more options out there. On OpenBSD there are options also. The benefits of having full disk encryption go way beyond of just protecting a ssh key without a passphrase.
It's worth noting that if an attacker has repeated physical access it's pretty much game over, even with FDE. There are way too many attacks he can do, the evil maid being just one of them. Also, in the case of theft, if the FDE password is weak and you're just using a password (truecrypt, luks, and others can have one or more keyfiles) there the old fashioned brute-force attack. As I mentioned before, I think it will be very difficult for you to implement a solution that is portable across all the platforms. And probably even if you can, I don't see it getting into upstream OpenSSH. Now, the data store you are wanting to implement for linux is a good idea. Cheers, -- Giancarlo Razzolini GPG: 4096R/77B981BC
