[tor-bugs] #20495 [Metrics/Censorship analysis]: China blocking of meek, 2016-10-19

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#20495: China blocking of meek, 2016-10-19
-----------------------------------------+---------------------
 Reporter:  dcf                          |          Owner:
     Type:  task                         |         Status:  new
 Priority:  Medium                       |      Milestone:
Component:  Metrics/Censorship analysis  |        Version:
 Severity:  Normal                       |     Resolution:
 Keywords:  meek                         |  Actual Points:
Parent ID:                               |         Points:
 Reviewer:                               |        Sponsor:
-----------------------------------------+---------------------

Comment (by dcf):

 I tested [https://ftp.mozilla.org/pub/firefox/releases/45.2.0esr/linux-
 x86_64/en-US/ Firefox 45.2.0esr] (the basis of current Tor Browser 6.0.5)
 and [https://ftp.mozilla.org/pub/firefox/releases/45.4.0esr/linux-x86_64
 /en-US/ Firefox 45.4.0esr] (the basis of current Tor Browser 6.5a3)
 through a SOCKS proxy into China. In other cases, this has been enough to
 stimulate blocking, because the TLS fingerprint of meek is (supposed to
 be) the same as that of the underlying Firefox. However, I was not able to
 find any blocking.

 ||Firefox 45.2.0 ||https://a0.awsstatic.com/ ||not blocked ||
 ||Firefox 45.2.0 ||https://ajax.aspnetcdn.com/ ||not blocked ||
 ||Firefox 45.4.0 ||https://a0.awsstatic.com/ ||not blocked ||
 ||Firefox 45.4.0 ||https://ajax.aspnetcdn.com/ ||not blocked ||

 The TLS fingerprints of Firefox 45.2.0esr and 45.4.0esr differ slightly.
 45.4.0esr has one additional Signature Hash Algorithm. Oddly, the TLS
 fingerprint of meek in Tor Browser 6.5a3 is the same as that of Firefox
 45.2.0, despite Tor Browser 6.5a3 being based on Firefox 45.4.0.
  *
 [[doc/meek/SampleClientHellos#Firefox45.2.0esronDebianjessie2016-10-28|Firefox
 45.2.0esr]]
  *
 [[doc/meek/SampleClientHellos#Firefox45.4.0esronDebianjessie2016-10-28|Firefox
 45.4.0esr]]
  *
 [[doc/meek/SampleClientHellos#TorBrowser6.5a3basedonFirefox45.4.0ESRonDebianjessie2015-10-28|Tor
 Browser 6.5a3 with meek]]

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Ticket URL: <https://trac.torproject.org/projects/tor/ticket/20495#comment:3>
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