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

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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Relevant Pages

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