service menu for secure-delete

[lcharles]

How do you add secure-delete to the service menu in Dolphin in 12.04?

[james147]

It wont matter if you are on a modern filesystem that uses journaling (ext3+) or copy on write (btrfs) as shredders do not work with these filesystems (at least no more then just deleting the file).

But you could create a service menu that executes the "shred" command line util.

[benny_fletch]

How do you add secure-delete to the service menu in Dolphin in 12.04?

See here: http://kde-apps.org/content/show.php/?content=75734

Warning: May or may not work in later versions of KDE.

[SteveRiley]

lcharles, would you mind explaining your requirement a bit more? Perhaps there's an alternate way to achieve what you need.

[lcharles]

OK, I guess the first question would be, is james147 right that something like secure-delete will not obliterate a file and works no better than "delete"? What I want to do is securely delete files. Additionally it would be nice if I didn't need to use the command like. I had been using secure-delete in some previous version of Kubuntu, but maybe I was kidding myself about it's effectiveness.

[SteveRiley]

"Secure deletion" is actually becoming a thing of the past. Modern file systems and hard drives contain many features that improve data integrity: journaling, copy-on-write, sector remapping, wear leveling, swap space... As a practical matter, the only ways to truly ensure data destruction are:

* Use an encrypting file system (not individual files, but the entire FS), or
* Physically destroy the drive

More: http://lwn.net/Articles/462437/

[lcharles]

OK, please excuse my lack of knowledge. The link you provided does make sense but I don't understand file systems that deeply. What's your (SteveRiley) oppinion of this link? http://techthrob.com/2010/10/04/do-s...d-filesystems/

[SteveRiley]

OK, please excuse my lack of knowledge. The link you provided does make sense but I don't understand file systems that deeply.

No need to apologize. We're all here to learn from each other.

What's your (SteveRiley) oppinion of this link? http://techthrob.com/2010/10/04/do-s...d-filesystems/

The article is technically correct: the default journaling mode of EXT4 removes one of the barriers to secure deletion. But many others remain. Consider, for example, the automatic defragging that many operating systems now perform as part of routine maintenance. Say that last night, your OS defragged a file from 16 separate physical locations into one contiguous location. Now today you "securely delete" that file. Alright, so the new location was overwritten with junk from /dev/urandom. What about the previous 16 separate locations? Sure, they've been marked as reusable, but it's likely your data is still sitting there. This data can be recovered.

The only ways to truly destroy data are to either (a) encrypt it and then destroy the key, or (b) destroy the physical storage medium.

[lcharles]

Thanks.

[NickStone]

What about simply overwriting the file you want to delete? I know that all "secure-delete" utilities overwrite the file first before deleting it. So with a journaled file system, overwriting a file will still have a copy of the original stored somewhere in the system?

Just read the info provided by Steve which has answered my question.