[tor-bugs] #3202 [Pluggable transport]: shared secret support in obfs2

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#3202: shared secret support in obfs2
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 Reporter:  asn                  |          Owner:  asn         
     Type:  defect               |         Status:  needs_review
 Priority:  normal               |      Milestone:              
Component:  Pluggable transport  |        Version:              
 Keywords:                       |         Parent:              
   Points:                       |   Actualpoints:              
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Comment(by asn):

 Okay, I also revived the unit tests and I killed the annoying bug I was
 rambling about in IRC.
 Basically, in the
 {{{
     if (state->pending_data_to_send) {
       crypt_and_transmit(state->send_crypto, state->pending_data_to_send,
 dest);
       evbuffer_free(state->pending_data_to_send);
       state->pending_data_to_send = NULL;
     }
 }}}
 blob in obfs2_recv(), the 'dest' argument of crypt_and_transmit() was
 pointing to the wrong evbuffer. So crypt_and_transmit() was spitting an
 encrypted version of my input back to me, which was in turn garbling my
 next input and in the end the data passed to the server had nothing to do
 with my actual input.

 My current fix is not really nice, since it sends up the queued data only
 on the next proto_send(), but I didn't see a way of getting the correct
 evbuffer from inside obfs2_recv().

-- 
Ticket URL: <https://trac.torproject.org/projects/tor/ticket/3202#comment:7>
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