[tor-bugs] #4594 [Tor Relay]: tor_tls_state_changed_callback(): detects of ClientHello is too late

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#4594: tor_tls_state_changed_callback(): detects of ClientHello is too late
-----------------------+----------------------------------------------------
 Reporter:  troll_un   |          Owner:                    
     Type:  defect     |         Status:  new               
 Priority:  major      |      Milestone:  Tor: 0.2.3.x-final
Component:  Tor Relay  |        Version:  Tor: 0.2.3.8-alpha
 Keywords:             |         Parent:                    
   Points:             |   Actualpoints:                    
-----------------------+----------------------------------------------------

Comment(by troll_un):

 But early detect have no sense:
 {{{
     /* We got more than one renegotiation requests. The Tor protocol
        needs just one renegotiation; more than that probably means
        They are trying to DoS us and we have to stop them. We can't
        close their connection from in here since it's an OpenSSL
        callback, so we set a libevent timer that triggers in the next
        event loop and closes the connection. */

     if (tor_run_in_libevent_loop(tls->excess_renegotiations_callback,
                                  tls->callback_arg) < 0) {
       log_warn(LD_GENERAL, "Didn't manage to set a renegotiation "
                "limiting callback.");
     }
 }}}
 Server anyway continues handshaking while looping ssl3_accept() and sends
 hellos and key stuff and anything that it can to do for nonblocking io.

-- 
Ticket URL: <https://trac.torproject.org/projects/tor/ticket/4594#comment:2>
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