secure deletion

[Wes Peters]

Warner Losh wrote:
> 
> In message <Pine.BSF.4.05.9905191535110.7728-100000 at ws-ilmar.ints.ru> "Ilmar S. Habibulin" writes:
> : May be it's an freebsd-fs@ question, but i think that it belings here to.
> : I heard that some linux fs (maybe extfs2?) have some secure deletion flag,
> : which being set on inode(file or dir) cause content of this file to be
> : wiped before deletion, so even if somebody manage to restore file, its
> : content would be unusable. I think, that it is nice feature, and i would
> : like to see it in freebsd. What would you say?
> :
> : PS. I have implementation of this feature for freebsd-2.2.5. May be i can
> : port it to 3.x.
> 
> Does it doe the DoD recommended patter of deletion?  That is overwrite
> the blocks with sever different series of bit patterns to make it
> impossible to recover using the usual techniques, or is it just a
> bzero of the blocks in question?  The former is secure deletion, the
> latter is too insecure for most people that want this feature...

The standard used to be 100 overwrites of 0xe5 then 0x5e, but they 
changed the standard just as I was leaving the defense industry in
1991.  Does Posix or SUS have anything to say about this?

-- 
       "Where am I, and what am I doing in this handbasket?"

Wes Peters                                                 Softweyr LLC
http://www.softweyr.com/~softweyr                      wes at softweyr.com
To Unsubscribe: send mail to majordomo at cyrus.watson.org
with "unsubscribe posix1e" in the body of the message