[tor-bugs] #2204 [Tor Relay]: Recent openssls (1.0.0b and 0.9.8p) break relay handshakes

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#2204: Recent openssls (1.0.0b and 0.9.8p) break relay handshakes
--------------------------------+-------------------------------------------
 Reporter:  stars               |        Type:  defect   
   Status:  new                 |    Priority:  critical 
Milestone:  Tor: 0.2.1.x-final  |   Component:  Tor Relay
  Version:                      |    Keywords:           
   Parent:                      |  
--------------------------------+-------------------------------------------

Comment(by Sebastian):

 Here a few quick notes: This gets triggered by this call
 {{{
     result = tor_tls_handshake(conn->tls);
 }}}
 inside connection_tls_continue_handshake. In the client use case,
 {{{
      result = tor_tls_renegotiate(conn->tls);
 }}}
 doesn't trigger the issue.

 The error we get is a decode error like it could be triggered by
 {{{
 +
 if(s->session->tlsext_hostname)
 +                                                       {
 +                                                       *al =
 SSL_AD_DECODE_ERROR;
 +                                                       return 0;
 +                                                       }
 }}}
 which is part of the openssl patch.

 Typical Tor log line:
 {{{
 [info] connection_tls_continue_handshake(): tls error [unexpected close].
 breaking connection.
 [info] TLS error while handshaking with [scrubbed]: parse tlsext (in SSL
 routines:SSL3_GET_CLIENT_HELLO)
 }}}

-- 
Ticket URL: <https://trac.torproject.org/projects/tor/ticket/2204#comment:5>
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