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White-Box Cryptography

Posted: Thu Sep 04, 2008 2:44 am
by LaBBa
"White-box cryptography is a technique to hide a secret key into a cryptographic software implementation in a white-box model. In such a model, an adversary has full control over the execution environment.

A white-box DES encryption binary with embedded secret key. If you like, try to extract the secret key, using all information you can find from this implementation (input-ouput attacks, so called black box attacks, are not allowed). "

here is there demo link (cygwin1.dll is needed):
https://www.cosic.esat.kuleuven.be/sopro/wbc/wbDES.exe

here is there website:
https://www.cosic.esat.kuleuven.be/sopro/
https://www.cosic.esat.kuleuven.be/sopro/wbc/

i'm currently working on this and look at the attached file that i have made :P

come and join to reverse this protection ... sooner the better

regards,
LaBBa.

Posted: Sun Sep 07, 2008 12:59 am
by rendari
Cloakware brags about this white boy stuffs on their website, and yet I wonder how effective it is in the real world... to prevent your softie from getting cracked.

White-Box DES Cryptanalysis

Posted: Sun Sep 07, 2008 4:28 am
by bwyseur
The implementations you refer to, are implemented according to the description of white-box DES implementations by Chow et al. [http://crypto.stanford.edu/DRM2002/whitebox.pdf], with some minor improvements [`clarifying obfuscation'-paper, by Link et al.; and some personal improvements].

I implemented this binary, to test my cryptanalysis results mid 2006. The details of the cryptanalysis are published at SAC'07, and is mentioned on the website you refer to. See also http://eprint.iacr.org/2007/104 for technical details. A different cryptanalysis result has been published at SA'07 too (See http://eprint.iacr.org/2007/035).

More information on white-box cryptography will appear on a to-be-launched website: http://www.whiteboxcrypto.com. This will include a PhD thesis on this topic, which I'm writing at this very moment.


You mention that input-output (black-box) attacks are not allowed. I disagree. Every cryptographic implementation should at least be able to withstand black-box attacks. Given full control over the implementation and its execution environment, an adversary could just execute the implementation as black-box as many times as he wishes to. Why would an adversary bother to deploy an more sophisticated white-box attack when simple is possible?

Protection against implementation attacks (side-channel and white-box) is an extra level of defense, on top of black-box protection. Hence, it only makes sense to implement "secure" ciphers (DES, AES, ...).

Best regards,
Brecht Wyseur

Another White Box scheme

Posted: Tue Apr 21, 2009 2:49 pm
by Dmitry
The scheme presented at link below is not a Rijndael. But this scheme has a similar principle. I'll publish a white box tables generator a little bit later if it is interesting for somebody.
http://rapidshare.de/files/46842216/wb_sample.rar.html

Posted: Tue Apr 28, 2009 5:30 pm
by LaBBa
nice ... i will look at this and will respond later..

Posted: Wed Apr 29, 2009 11:21 am
by Maximus
I am interested in it :)

Posted: Fri May 15, 2009 12:05 pm
by Dmitry

Posted: Thu May 21, 2009 2:40 am
by Maximus
Thank you!! the code looks VERY interesting, I will have to study it in detail (work permitting), many thanks.
This looks like to be a very interesting technique, I'm happy to learn it with a 'live' example, thanks again :)

Posted: Tue Mar 22, 2011 8:58 pm
by rendari
Anyone still have the white box files dmitry posted? Or are they lost for all of time :(

Posted: Wed Mar 23, 2011 5:18 am
by Dmitry
rendari wrote:Anyone still have the white box files dmitry posted? Or are they lost for all of time :(

A paper which describes my approach is presented here: http://eprint.iacr.org/2010/419.pdf.
Source code and sample are presented here: http://www.guardant.ru/download/personal/white_box.zip.

Posted: Fri Mar 25, 2011 7:37 pm
by rendari
Thank you very much Dmitry!

And kayaker too ;)