/Tracking/Fingerprinting/active/math_routines/

• $ fingerprint@info:~ echo $MATH-ROUTINES

• Name:

  Math Routines
  

  Original feature purpose:

  Math is a built-in object that has properties and methods for mathematical constants and functions. For more details see, e.g., MDN web docs

  
  

  FP-Explanation:

  The Specification of the Math Object states in Section 20.2.2 ECMAScript 2015:
  

  'The behaviour of the functions [...] is not precisely specified here except to require specific results for certain argument values that represent boundary cases of interest. For other argument values, these functions are intended to compute approximations to the results of familiar mathematical functions, but some latitude is allowed in the choice of approximation algorithms.'

  This leads to a precision which is implementation- and hardware-dependent. This means, due to different rounds or intermediate values, math routine results suffer inconsistencies across operating systems, math libaries, JS engines and browser versions.

  
  

  FP-Type:

  active
  

  FP-Categories:

  js, js-attrib, hardware-dependent, software-dependent, consistent
  

  Counter-measures:

  • Reduce/unify floating point precision
    Description: Limit/unify the accuracy of mathematical calculations in the browser to a specific decimal place
    Problem 1: Multiple, in the best case, all browser vendors must agree on a consistent accuracy
    Problem 2: Operating system-dependent calculations remain
    
  
  

  Publications/References:

  • Math routines are OS fingerprintable (Tor Bug Tracker)
  • Math routine Fingerprinting (Darkwave Technologies)
  • Floating point differences between platforms (Bugzilla)
  • Browser Fingerprint (FP Central)
  
  
• $ fingerprint@info:~ run math-routines-demo

Demo:

>> Jump to Math Routines Demo <<