full-disclosure - Small (but useful) utility

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Message-ID: <I1YRX5$17C31654ADCDDBBA8A0FD2B683241B7A@laposte.net>
From: m.mohr at laposte.net (M. Mohr)
Subject: Small (but useful) utility

When I couldn't find a decent file wiping utility on my own
machine, I decided to write one.  Yes, I did search the net
and came up with a few... but they seem to be poorly written
and overly complicated.  So, in just 64 lines, I wrote one
that would be useful for me, that would work well, and that is
simple enough to understand.

What has this to do with full-disclosure, you might ask? 
Everything!  Call me paranoid, but if/when the feds come
a-knocking, I want to be able to execute a single command that
will securely delete non-encrypted data on my hard disk.  i.e.
all the 0-day exploits, the leaked Microsoft and Half-Life
source code, and the porn from Hitler's bunker.

You might want to name this program something inconspicuous
(like 'index') and place it in /sbin, then add something like
the following to rc.local:

sleep 300 && screen -d -m find /home/foo -type f | xargs
/sbin/index

Just make sure to resume the screen as root within 5 minutes
of system boot time :)

Depending on your paranoia, you may want to change the PASSES
define, which controls how many times the file is overwritten.
 Keep in mind that my program will overwrite your file 3 times
for each increment of PASSES (once with zeroes, once with
ones, and once with random data).  For example, the default
setting (2) will overwrite your file 6 times.

With that in mind, a setting of 2 - 3 should be plenty.  I
tested this program with a 500 mb file, which took 52 seconds
to complete on my system (using the source code attached). 
The same file with PASSES defined as 15 took at least 4 and a
half minutes (well... I killed it just after 4:45 because it
was taking too long :P).

On to licensing: I release this code under the GPL.  A credit
to me (the original author) would be appreciated (but is not
required) in any derivative work.

You can send any questions or comments to me.  The source
should compile cleanly on Linux and likely other Unices,
however it will almost certainly not work on Windows without
modifications.

Acc?dez au courrier ?lectronique de La Poste : www.laposte.net ; 
3615 LAPOSTENET (0,34?/mn) ; t?l : 08 92 68 13 50 (0,34?/mn)

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