[tor-bugs] #1138 [Tor Client]: If bridge authority is unreachable, client doesn't fallback to bridge

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#1138: If bridge authority is unreachable, client doesn't fallback to bridge
-------------------------+--------------------------------------------------
  Reporter:  arma        |       Owner:  mwenge            
      Type:  defect      |      Status:  needs_review      
  Priority:  major       |   Milestone:  Tor: 0.2.2.x-final
 Component:  Tor Client  |     Version:  0.2.1.19          
Resolution:  None        |    Keywords:  easy              
    Parent:              |  
-------------------------+--------------------------------------------------

Comment(by arma):

 {{{
 +  tor_assert(conn->requested_resource);
    /* Requests for bridge descriptors are in the form 'fp/', so ignore
       anything else. */
    if (conn->requested_resource &&
 strcmpstart(conn->requested_resource,"fp/"))
 }}}

 The first part of that if is now redundant.

 It seems the defensive programming way to do that would be to say
    if (!conn->requested_resource || strcmpstart(...))

 I'm not comfortable with the assert in general, because
 conn->requested_resource only gets assigned once we're actually sending
 the request. That *may* be fine for begin_dir cells, since they shouldn't
 fail instantaneously if the request is going over Tor.

 Still, notice how connection_dir_request_failed() gets called from
 directory_initiate_command_rend() in the case where connect() fails.
 That's at least one codepath.

 This area sure is a mess. See also the
 {{{
         /* XXX we only pass 'conn' above, not 'resource', 'payload',
          * etc. So in many situations it can't retry! -RD */
 }}}
 comment right around there.

 I vote for the 'defensive programming way' I mentioned above, as the
 short-term fix.

-- 
Ticket URL: <https://trac.torproject.org/projects/tor/ticket/1138#comment:15>
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