Re: secure erasure of files?

[Padraig Brady <padraig@antefacto.com>]

And a patch to call it automatically:
http://www.tpgn.net/exploits/linux/secrm.kernel.patch.2.2.14.txt

On a related note is there any way to clear the unused portion
of the last block of a file. Obviously it's file system dependent,
but what happens in general on ext2?

Padraig.

Davidovac Zoran wrote:
> there is srm (secure rm) somewhere on the net
> here srm.sourceforge.net
> srm - secure file deletion for posix systems
> 
> happy srm,
> 
>       Zoran
> 
>    srm is a secure replacement for rm(1). Unlike the standard rm, it
>    overwrites the data in the target files before unlinking them. This
>    prevents command-line recovery of the data by examining the raw block
>    device. It may also help frustrate physical examination of the disk,
>    although it's unlikely that it can completely prevent that type of
>    recovery. It is, essentially, a paper shredder for sensitive files.
> 
>    srm is ideal for personal computers or workstations with Internet
>    connections. It can help prevent malicious users from breaking in and
>    undeleting personal files, such as old emails. It's also useful for
>    permanently removing files from expensive media. For example, cleaning
>    your diary off the zip disk you're using to send vacation pictures to
>    Uncle Lou. Because it uses the exact same options as rm(1), srm is
>    simple to use. Just subsitute it for rm whenever you want to destroy
>    files, rather than just unlinking them.
> 
> 
> On Tue, 12 Feb 2002, Roy Sigurd Karlsbakk wrote:
> 
> 
>>Date: Tue, 12 Feb 2002 14:12:49 +0100 (CET)
>>From: Roy Sigurd Karlsbakk <roy@karlsbakk.net>
>>To: linux-kernel@vger.kernel.org
>>Subject: secure erasure of files?
>>
>>hi all
>>
>>Does anyone know if it'll be hard to enable a <em>secure</em> deletion of
>>files? What I mean is not merely overwriting it with NULLs, but rather
>>using a more sophisticated overwrite, like the IBAS ExpertEraser software
>>(http://www.ibas.com/erasure/)
>>
>>Is this hard/possible/doable?
>>
>>roy