Messages in this thread | | | Date | Sat, 7 Feb 2004 18:22:22 +0100 | From | Pavel Machek <> | Subject | Re: PATCH - ext2fs privacy (i.e. secure deletion) patch |
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Hi!
> > As I now understand, you are proposing a file system which has per file > > encryption where the key is stored in the inode. The inode is then the > > only location with senstive data which needs to be removed. > > Yes. > > > Also, this proposal seems to me more related to how to implement an > > encrypted file system, than how to implement secure deletion on existing > > file systems. > > Not really, this is pointing out an alternative means of secure > deletion _if_ you have encryption. The points I wanted to make were, > most important first: > > - Overwriting data does not always do what you think it does. > Several block devices _do not_ overwrite the same storage blocks. > Thus it is dangerous to call something "secure deletion" > when it might not do anything at all.
But you have same vulnerability, crypto does not help here. If your i-node happens to be put on other place, attacker still gets the key intact etc.
There's not much you can do. [It may be even worse with that crypto... If you kick the table while your top-secret .mpg.tgz collection is accessed, you are likely to cause bad sector within i-node, attacker can get the key, and decrypt it all. With on-place overwriting he only gets one block.] Pavel -- When do you have a heart between your knees? [Johanka's followup: and *two* hearts?] - To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/
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