[dm-crypt] Truecrypt audit

Chris Drake Tech at CryptoPhoto.com
Fri May 16 16:40:56 CEST 2014

Hi Arno,

I would go even a step further.  Since we know Truecrypt is popular,
and America alone spends $50billion+ annually to get 50,000+ of the
worlds smartest people to ensure they have back-door access to as much
as possible, I'd go so far as to say that some kind of back door is a

Hiding cunning back doors in source code is one of the most
interestingly compelling intellectual tasks you could ever dream to
work on.  Lots of countries spend lots of money hiring lots of very
smart people to do just that...  (and, just one example, the source
uses /dev/random - the current worlds-most-famous-place for hiding
backdoors; yet they didn't care to dive into the kernel code behind
that, not that doing so is even possible on closed-source windows

The very start of the analysis reports that they didn't attempt to
build the binary we all use, from the source they examined.  That's
pretty much as far as you need to read :-(

Kind Regards,
Chris Drake

Friday, May 16, 2014, 9:11:39 PM, you wrote:

AW> Hi all,

AW> I just want to warn everybody not to place too great stock 
AW> into these results. I have participated in similar, non-public
AW> analyses and they can only ever go so deep. Cleverly hidden or
AW> disguised backdoors may easily be overlooked, as resources are
AW> constrained and attackers will make sure tool-support fails
AW> by running their backdoors against the usual tools to make sure
AW> they are not found. The same, incidentally, is done by malware
AW> writers that check their malware against current virus scanners
AW> before deploying them. 

AW> What you get with the report is a code-quality assessement which
AW> is realistic under the assumption that the implementer was
AW> non-malicious. That in itself has value, but it is a different
AW> kind of statement than people may assume when looking at the
AW> report. 

AW> So what do do if you want to be sure security software you 
AW> use has no backdoors? By now I am convinced that the only
AW> cost-effective way is to have highly competent and careful 
AW> people you trust implement it for you. Sure, that is expensive,
AW> but there are good reasons to believe that an analysis that
AW> has a good chance of finding most or all backdoors is a lot 
AW> more effort and in addition requires a higher level of skill,
AW> making it orders of magnitide more expensive.

AW> The following quote is even more true for security aspects:

AW>   "Debugging is twice as hard as writing the code in the first place.
AW>    Therefore, if you write the code as cleverly as possible, you are,
AW>    by definition, not smart enough to debug it." - Brian W. Kernighan

AW> The only way to get the simplicity you need to be sure there
AW> are no backdoors is to enforce it by writing it yourself.

AW> Yes, I know that is far from ideal but it is how the
AW> situation presents itself to me.

AW> Arno

AW> On Fri, May 16, 2014 at 07:02:57 CEST, Heinz Diehl wrote:
>> Hi,
>> because cryptsetup is supporting truecrypt, I thought this one could
>> be of interest:
>> http://tinyurl.com/n8z4tcu
>> _______________________________________________
>> dm-crypt mailing list
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>> http://www.saout.de/mailman/listinfo/dm-crypt

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