[tor-bugs] #10676 [Tor]: Verify urandom-style RNG is seeded before generating ID keys

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#10676: Verify urandom-style RNG is seeded before generating ID keys
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     Reporter:  nickm        |      Owner:
         Type:  enhancement  |     Status:  needs_review
     Priority:  major        |  Milestone:  Tor: 0.2.5.x-final
    Component:  Tor          |    Version:
   Resolution:               |   Keywords:  tor-server rng urandom startup
Actual Points:               |  Parent ID:
       Points:               |
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Comment (by user101):

 I think this relates to cypherpunks comment above and I don't have any
 references of my own handy, but it is not sufficient for /dev/random to
 *think* it has or has had entropy.  It has been shown that the "entropy"
 generated at bootup by many small, diskless  devices such as consumer
 grade "wireless routers" will tend to be similar between identical units,
 likely contributing to the problems noted in the factorable.net link in
 cyperpunks post.  This is related to, but not identical with, the problems
 noted in the Linux man page for /dev/random leading to the recommendation
 to carry entropy over across boots.  So somehow on these "limited entropy
 devices" you need to wait long enough for *real* entropy to be generated
 that will be sufficiently different from the "entropy" generated on other
 like devices.  /dev/random will *think* it has entropy long before this.

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Ticket URL: <https://trac.torproject.org/projects/tor/ticket/10676#comment:10>
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