[tor-bugs] #7549 [Flashproxy]: Facilitator should not give client registrations to Tor exits

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#7549: Facilitator should not give client registrations to Tor exits
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 Reporter:  dcf          |          Owner:  jct
     Type:  enhancement  |         Status:  new
 Priority:  normal       |      Milestone:     
Component:  Flashproxy   |        Version:     
 Keywords:               |         Parent:     
   Points:               |   Actualpoints:     
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Comment(by jct):

 I just attached a patch with a candidate code in order to solve the
 ticket. The main idea for the patch is the following:

    * A thread is created by the Facilitator in order to maintain a locally
 cached database of exits:
       * The locally cached database is managed by the class
 '''TorExitsSet'''
       * The thread is running the function '''get_exit_nodes''' in order
 to get a list of Tor Exit nodes
          * The function is querying by HTTP to a Tor Directory Server in
 order to get the list
       * The thread is running each '''ELAPSED_REFRESHING_TIME''' seconds
    * The function do_GET was modified in order to check if the Proxy
 address is belonging to a Tor Exit node:
       * In this case not Client/Relay address is sent to the Proxy, but an
 error signalling the situation:
          * The flashproxy.js was modified in order to disable the Proxy
 when an error is received:
             * If the Proxy is malicious it could avoid to disable itself,
 but the benign ones are disabling themselves (hopefully)

-- 
Ticket URL: <https://trac.torproject.org/projects/tor/ticket/7549#comment:1>
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