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Doug Barton <dougb@FreeBSD.org> writes: > 3. Write a script to reboot, and once the system is fully booted do 'dd > if=3D/dev/random of=3Dsaved-random-out.$i count=3D4096' then reboot again > immediately. Values of i from 1 to 10,000 ought to do it. > 4. sha256 the saved-random-out files and see how many duplicates there ar= e. I doubt there will be any exact duplicates, but closer statistical analysis might reveal a slight bias. For instance, if my intuition serves, the Hamming distance between any pair of samples, when averaged over a large number of samples, should be half the sample length. I'm sure a professional statistician or cryptanalyst could come up with more accurate ways of detecting bias. The script in question, by the way, could simply be a few extra lines at the end of /etc/rc.d/initrandom; and I'd do it in a VM, to reduce cycle time to a minimum. DES --=20 Dag-Erling Sm=C3=B8rgrav - des@des.no _______________________________________________ freebsd-security@freebsd.org mailing list http://lists.freebsd.org/mailman/listinfo/freebsd-security To unsubscribe, send any mail to "freebsd-security-unsubscribe@freebsd.org"