[Cryptography] Fwd: [IP] 'We cannot trust' Intel and Via's chip-based crypto, FreeBSD developers say

[Stephan Mueller]

Am Donnerstag, 19. Dezember 2013, 07:56:36 schrieb Arnold Reinhold:

Hi Arnold,


>How do we safely initialize Yarrow or a another software RNG if the
>CPU's hardware RNG is compromised and there is no other source of
>entropy? This is a situation that is increasingly common in all
>solid-state black box devices, and is especially tricky at first
>startup, when keys used to manage such units are often generated.

There are various implementations of RNGs that use CPU execution timing 
variations as noise source. That phenomenon is available right from the 
start of the CPU. In fact, the patch in my Jitter RNG [4] for the Linux 
/dev/random would fill the input_pool with entropy during initialization 
at system boot time, early in the boot cycle. This could be done for a 
Yarrow as well. I guess the other RNGs could be used in a similar 
fashion.

So, there are noise sources which do not depend on some black box.

[1] http://www.issihosts.com/haveged/
[2] http://dankaminsky.com/2012/08/15/dakarand/
[3] http://jytter.blogspot.se/
[4] http://www.chronox.de/


Ciao
Stephan