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util-linux: predictable mcookie results

Posted Feb 20, 2003 22:13 UTC (Thu) by Ross (subscriber, #4065)
Parent article: util-linux: predictable mcookie results

I mentioned this in another post for this bug fix.
/dev/urandom should be completely unpredictable
provided that you have not:

1) broken SHA-1
or
2) obtained access to the entropy pool

Am I just confused or was this update ultra-paranoia?

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util-linux: predictable mcookie results

Posted Mar 3, 2003 12:49 UTC (Mon) by rasumner (guest, #5410) [Link]

I agree, I see almost no reason to prefer /dev/random over /dev/urandom. The only cases that I can think of are

i) 128-bits isn't enough entropy (it is, honest)
ii) The machine has just booted (perhaps even for the first time), so that the entropy pool doesn't have enough entropy in it. This might be reasonable say for RedHat's generating an ssh key the first time sshd is started.