[tor-bugs] #23061 [Core Tor/Tor]: crypto_rand_double() should produce all possible outputs on platforms with 32-bit int

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#23061: crypto_rand_double() should produce all possible outputs on platforms with
32-bit int
-------------------------------------------------+-------------------------
 Reporter:  teor                                 |          Owner:  nickm
     Type:  defect                               |         Status:
                                                 |  needs_revision
 Priority:  Medium                               |      Milestone:  Tor:
                                                 |  0.3.3.x-final
Component:  Core Tor/Tor                         |        Version:  Tor:
                                                 |  0.2.2.14-alpha
 Severity:  Normal                               |     Resolution:
 Keywords:  tor-relay, security-low, privcount,  |  Actual Points:  0.5
  031-backport, 030-backport, 029-backport, 028  |
  -backport-maybe, 026-backport-maybe, review-   |
  group-22                                       |
Parent ID:  #23126                               |         Points:  0.1
 Reviewer:                                       |        Sponsor:
                                                 |  SponsorQ
-------------------------------------------------+-------------------------

Comment (by yawning):

 https://i.imgur.com/WTDnnwE.gif

 Replying to [comment:45 catalyst]:
 > Section 5.2 of
 https://pdfs.semanticscholar.org/2f2b/7a0d5000a31f7f0713a3d20919f9703c9876.pdf
 describes one way to sample uniformly from all the representable floating
 point numbers in [0, 1).  It's not clear to me whether including the
 numbers with ULPs less than 2^-53^ is required for the success of the
 snapping mitigation described in that paper.

 See "Smoothing" under Section 5.1.

 > It isn't required, and might even be counterproductive.

 Indeed.

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Ticket URL: <https://trac.torproject.org/projects/tor/ticket/23061#comment:47>
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