using /dev/random

[RW]

On Tue, 23 Sep 2008 13:39:35 +0100
RW <fbsd06 at mlists.homeunix.com> wrote:

> On Tue, 23 Sep 2008 00:51:02 -0700
> "Ted Mittelstaedt" <tedm at toybox.placo.com> wrote:
 
> > If you really want to roll-your-own and not use these functions
> > then you could read blocks from /dev/random and run
> > a Chi-square and Monte Carlo test on each
> > block and discard the ones that don't pass.
> > 
> > I've done my experimenting with the ENT program:
> > 
> > http://www.fourmilab.ch/random/
> 
> I'm sceptical about this, if Rijndael in counter-mode produced output
> that's distinguishable from random numbers over a few thousand bytes
> it would surely never have made it into the AES competition, let
> alone win it. 

I tried it myself (the windows binary runs under wine), it looks OK to
me, they look like normal statistical fluctuations. You need to worry
of they are consistently low or high, or if you *never* get extreme
values. 

Discarding the blocks that don't "pass" would produce less random
numbers, not better.