[tor-bugs] #8104 [Obfsproxy]: obfs2: Corrupted magic value '0xb312f1ad': Closing circuit

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#8104: obfs2: Corrupted magic value '0xb312f1ad': Closing circuit
-----------------------+----------------------------------------------------
 Reporter:  asn        |          Owner:  asn             
     Type:  defect     |         Status:  new             
 Priority:  normal     |      Milestone:                  
Component:  Obfsproxy  |        Version:  Obfsproxy: 0.1.4
 Keywords:             |         Parent:                  
   Points:             |   Actualpoints:                  
-----------------------+----------------------------------------------------
 {{{
 obfs2: Corrupted magic value '0xb312f1ad': Closing circuit
 }}}

 I've been getting a couple of messages like the above in my pyobfsproxy
 bridge. It seems that some obfs2 clients don't handle their encryption
 correctly. The bug seems to occur rarely, but it's  a bug that must be
 solved.

 The problem is that I haven't figured out whether it's a bug in
 pyobfsproxy or in obfsproxy yet. I've tried to reproduce the problem by
 firing up thousands of obfs2 clients (both pyobfsproxy and obfsproxy) but
 it doesn't happen.

 (Bridges running obfsproxy won't throw such a warning, because they just
 silently close the circuit:
 https://gitweb.torproject.org/obfsproxy.git/blob/HEAD:/src/protocols/obfs2.c#l635
 )

 (Flagging this as an obfsproxy bug for now.)

-- 
Ticket URL: <https://trac.torproject.org/projects/tor/ticket/8104>
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