[tor-bugs] #6079 [Ooni]: Implement DNS lookup Test

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#6079: Implement DNS lookup Test
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 Reporter:  hellais  |          Owner:  hellais               
     Type:  task     |         Status:  needs_information     
 Priority:  normal   |      Milestone:  Sponsor H: August 2012
Component:  Ooni     |        Version:                        
 Keywords:           |         Parent:  #6075                 
   Points:           |   Actualpoints:                        
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Changes (by isis):

  * status:  new => needs_information


Comment:

 It also can optionally be configured to do a reverse DNS resolution for
 the IPs obtained from the first part of the experiment. This is not always
 useful, but I implemented it in the hope that it might reduce false
 positives due to GeoIP load balancing, e.g. 'google.com' resolving to a
 different set of IPs based on the client's location. The idea was that
 those IPs might in some cases point back to the same, or similar,
 hostnames. It needs a better heuristic for determing what exactly "similar
 hostname" means, but I have a test result file where the reverse DNS
 resolution was correctly able to eliminate false positives. (See attached
 reversednstestsuccessful.txt, the first test result for 'google.com' shows
 what happens when reverse DNS detects different hostnames, and the second
 for 'torrentz.eu' shows reverse DNS detecting matching hostnames.)

 I started porting this test to twisted this afternoon, but I'm quite sick
 in Rio and haven't finished and tested, so I have not yet committed the
 port. Likely tomorrow, or in one of the next few airports.

 Also, a TODO: when I was writing the CaptivePortal test, I learned some
 more DNS tricks that I wrote into methods there, we should check if any
 could also be useful in DNStamper.

-- 
Ticket URL: <https://trac.torproject.org/projects/tor/ticket/6079#comment:1>
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