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

[Mike McGrath]

Theodore Tso wrote:
> 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....
>   

We actually had a very vocal minority about all of that which ended up 
putting us in the unfortunate position of generating a random UUID 
instead of using a hardware UUID from hal :-/

   -Mike
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