Re: Why does reading from /dev/urandom deplete entropy so much?

Theodore Tso
2007-12-08T17:33:23Z

On Sat, Dec 08, 2007 at 02:37:57AM -0500, Jon Masters wrote:
> > BTW, You may be better off using "uuidgen -t" to generate the UUID in
> > the smolt RPM, since that will use 12 bits of randomness from
> > /dev/random, plus the MAC, address and timestamp. So even if there is
> > zero randomness in /dev/random, and the time is January 1, 1970, at
> > least the MAC will contribute some uniqueness to the UUID.
>
> I haven't checked how uuidgen uses the MAC, but I would suggest that
> that is not something Fedora should jump at doing - although it would
> help ensure unique UUIDs, it also contributes to the tinfoil hat
> responses that usually come up with things like smolt.

Huh? What's the concern? All you are submitting is a list of
hardware devices in your system. That's hardly anything sensitive....

- Ted