Re: Thoughts about the b43 RNG

[Harvey Harrison <harvey.harrison@gmail.com>]

On Thu, 2009-01-08 at 17:28 -0800, Harvey Harrison wrote:
> On Fri, 2009-01-09 at 02:11 +0100, Michael Buesch wrote:
> > I was doing some random tests on the b43 hardware RNG.
> > These are the results.
> > 
> > I patched the firmware to not access the RNG register anymore.
> > The unpatched firmware does two things. It reads the RNG register to get random values
> > and it writes 0 to the register every now and then for whatever reason.
> > Both reads and writes were patched out during my test. So the driver was
> > the only one accessing the RNG.
> > 
> > This is the result of reading a few bytes from the RNG with the patched fw:
> 
> > I'm not sure about this. There aren't any obvious patterns.
> > But maybe I'm just blind. Does somebody else see some pattern or
> > has some RNG test program to recognize such patterns?
> > 
> > So let's do another test. Let's modify the previous test to
> > write 0xFFFF instead of 0:
> > 
> 
> NIST has a pretty good test suite I think.

Packaged for debian as dieharder if you want the command-line version.

Harvey