[Cryptech Core] deeper entropy analysis

[Randy Bush]

> Some time ago I was wildly confused by my DMA based entropy sources would 
> prefer alternating bit patterns over repeating ones, as I'm sure you've seen 
> on the tech list.
> 
> I asked someone with considerably more knowledgeable than me about how one 
> could perhaps analyse the output to gain insights into how this could be. That 
> person did not have time to contribute to the problem, but he suggested we 
> could perhaps involve this guy (for paid work)
> 
>   http://www.csc.kth.se/~terelius/
> 
> I haven't talked with him at all, but while I think we can be confident that 
> our TRNG will output excellent random data, if we want to be as confident about 
> the entropy I think we will need help from someone with higher mathematical 
> skills than I possess  - possibly that guy.
> 
> If you think it is a good idea then maybe I can try to meet with him for lunch 
> or something and see if he is interested and see what he could do for
> us?

as you say, whiten it, mix it, teach it to chacha, and we'll probably
have good bits.  but better understanding of the input would be good.
and it might reduce the chance of late surprises, one hopes.

it's research, so let's not poke too hard at the upsides.  though it
would be good to make the research goal(s) clear with terelius.

are there downsides?  your time?  presumably funding if lief can not get
terelius's time donated?

randy