Re: TPMs and random numbers

[David Safford <safford@us.ibm.com>]

On Wed, 2013-09-11 at 10:49 -0700, Andy Lutomirski wrote:
> On Wed, Sep 11, 2013 at 10:22 AM, David Safford <safford@us.ibm.com> wrote:
> >>On 09/09/2013 02:11 PM, H. Peter Anvin wrote:
> 
> A TPM that has an excellent internal entropy source and is FIPS 140-2
> compliant with no bugs whatsoever may still use Dual_EC_DRBG, which
> looks increasingly likely to be actively malicious.

I don't know of any that do so (it's more complex and slower than
the alternatives). 

> I'd be *much* happier if my system read a few hundred random bytes
> from the TPM at startup and fed those bytes into the kernel's entropy
> pool.  This should IMO happen at startup as early as possible.

I agree completely that the ideal case is a system with good entropy
sources, including a TPM, and all these mixed as early as possible.
But I also think that the existing (certified) TPMs are good enough 
for direct use.

dave