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bogus random entropy sources

Posted Oct 5, 2010 19:01 UTC (Tue) by patrick_g (subscriber, #44470)
In reply to: bogus random entropy sources by jzbiciak
Parent article: Solid-state storage devices and the block layer

>>> I don't understand why more processors don't include a proper hardware random number generator. It's a classic case of something that is significantly easier to do in hardware, I'd think.

I think Intel will is working on this.
See these link : http://www.technologyreview.com/computing/25670/

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Posted Oct 6, 2010 3:36 UTC (Wed) by PaulWay (✭ supporter ✭, #45600) [Link]

Purely an anecdote, but the other day I had the occasion to use shred to shred two disks at once. The machine was a modern Intel Core Quad system, and the disks were writing at 60MBytes/sec with 3% CPU load. Since modern shred just writes a number of layers of pure random data from /dev/urandom, I have to assume that there was either hardware crypto or randomness generation going on there. Who knew?!

Have fun,

Paul

bogus random entropy sources

Posted Oct 6, 2010 3:47 UTC (Wed) by jzbiciak (✭ supporter ✭, #5246) [Link]

Well, /dev/urandom doesn't block when the kernel entropy pool runs out. The hardware crypto acceleration may've been getting used, but that's orthogonal to the question of gathering entropy.

bogus random entropy sources

Posted Oct 6, 2010 19:34 UTC (Wed) by paulj (subscriber, #341) [Link]

Hehe, so shred was using entropy collected from the disk controllers, collected from shred writing to disks..