[tor-bugs] #10402 [Tor]: Force disable use of RDRAND in OpenSSL when HardwareAccel is enabled

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#10402: Force disable use of RDRAND in OpenSSL when HardwareAccel is enabled
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     Reporter:  anon    |      Owner:
         Type:  defect  |     Status:  new
     Priority:  major   |  Milestone:
    Component:  Tor     |    Version:
   Resolution:          |   Keywords:
Actual Points:          |  Parent ID:
       Points:          |
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Comment (by anon):

 One last note: the OS kernel will likely use RDRAND to keep /dev/random
 populated.  This is a Good Thing (TM) as long as you make sure you're
 using a recent kernel that integrates RDRAND properly, e.g.:
 1. Mix RDRAND into a hash across the pool, not XOR'd against output
 2. Mix the mix back into pool (prevent backtrack attacks)
 3. Atomically extract portion of pool and mix
 4. Fold final extracted output in half for conservative operation

 See
 https://git.kernel.org/cgit/linux/kernel/git/torvalds/linux.git/tree/drivers/char/random.c#n1038

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Ticket URL: <https://trac.torproject.org/projects/tor/ticket/10402#comment:5>
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