[tor-bugs] #13018 [Tor Browser]: Determine if high-precision Math routines are fingerprintable

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#13018: Determine if high-precision Math routines are fingerprintable
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     Reporter:           |      Owner:  tbb-team
  mikeperry              |     Status:  new
         Type:  task     |  Milestone:
     Priority:  normal   |    Version:
    Component:  Tor      |   Keywords:  tbb-fingerprinting, tbb-easy,
  Browser                |  ff31-esr, TorBrowserTeam201410Easy
   Resolution:           |  Parent ID:
Actual Points:           |
       Points:           |
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Comment (by gk):

 I did not test all functions but just some using
 https://people.torproject.org/~gk/misc/MathHighPrecisionAPI.html. While we
 have differences between OSes we have it seems differences between 32bit
 and 64bit architectures as well. I tested on OS X 10.6.8, 32 bit Debian
 testing, 32 bit Ubuntu Precise, 64 bit Ubuntu Precise, Windows 7 64 bit
 and Windows 8 64 bit. Small differences between Linux/OS X /Windows aside,
 the 64bit Ubuntu Precise gives me:
 {{{
     asinh(1) = 0.881373587019543
     acosh(1e300) = 691.4686750787736
     atanh(0.5) = 0.5493061443340548
     expm1(1) = 1.718281828459045
     log1p(10) = 2.3978952727983707
     sinh(1) = 1.1752011936438014
     cosh(10) = 11013.232920103324
     tanh(1) = 0.7615941559557649
 }}}
 While my 32bit systems give
 {{{
     asinh(1) = 0.8813735870195429
     acosh(1e300) = 691.4686750787737
     atanh(0.5) = 0.5493061443340549
     expm1(1) = 1.718281828459045
     log1p(10) = 2.3978952727983707
     sinh(1) = 1.1752011936438014
     cosh(10) = 11013.232920103328
     tanh(1) = 0.7615941559557649
 }}}

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Ticket URL: <https://trac.torproject.org/projects/tor/ticket/13018#comment:7>
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