[tor-bugs] #6180 [Ooni]: Detecting censorship in HTTP pages

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#6180: Detecting censorship in HTTP pages
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 Reporter:  hellais  |          Owner:  hellais             
     Type:  task     |         Status:  new                 
 Priority:  normal   |      Milestone:  Sponsor H: June 2012
Component:  Ooni     |        Version:                      
 Keywords:           |         Parent:                      
   Points:           |   Actualpoints:                      
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 The HTTP test of OONI does a TCP connection to the target host and send an
 HTTP request to obtain a webpage. If a webpage is retrieved this may be
 that of the censor.
 The issue is understanding if such a page is the legitimate response of
 it's a block page. How do we do this?

 The naive way to do so is to make a connection over Tor and check if that
 matches the one that is made over the live network, this has some problems
 though, for example if the site is geolocalized it will be different for
 Tor.

 Another simple approach is to have a database of content lengths of
 websites, but this also will fail if the censored page is very similar to
 the real web page.

 Another approach is to find a smart fuzzy matching algorithm for the Test
 page.

 Other ideas?

-- 
Ticket URL: <https://trac.torproject.org/projects/tor/ticket/6180>
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