[tor-bugs] #3302 [Pluggable transport]: obfs2 delays sending pending data

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#3302: obfs2 delays sending pending data
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 Reporter:  asn                  |          Owner:  asn
     Type:  defect               |         Status:  new
 Priority:  normal               |      Milestone:     
Component:  Pluggable transport  |        Version:     
 Keywords:                       |         Parent:     
   Points:                       |   Actualpoints:     
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Comment(by asn):

 Replying to [comment:4 nickm]:
 > I really prefer the solution I outlined where obfs2_recv() can return
 something that indicates that the caller needs to do an obfs2_send() right
 away without waiting any data.
 >

 Yes, I like that solution myself, but the implementation seems dirtier
 than it sounds on words. Basically, the caller of obfs2_send() is
 proto_send(). proto_send() can do the same things that obfs2_send() can
 do, so we have to go back to plaintext_read_cb(). We can indeed call
 obfs2_send() correctly from there, but isn't it ugly?
 I know I'm stuck on the concept of abstraction when we just have one
 protocol, but still defining a protocol specific return code (since
 calling proto_send() right away shouldn't make sense on other protocols)
 on network.c gives me twitches.

 > Having the listeners have a list of connections just seems wrong, if the
 whole point is to serve as a socks_state-to-connection map.  If the
 protocol send and recv methods really truly need access to the conn_t,
 then let's just pass them the conn_t!  The functions that call proto_send
 and proto_recv have the conn_t already: no need to make the functions they
 call hunt for it.

 You are right, doing all that just to get a socks_state-to-connection map
 is stupid. I just found it intuitive in the sense that the point of a
 listener is to accept connections and that would give us a way to go from
 a listener to a connection.

 Passing `conn_t` to the protocols is ugly as well, but it provides us with
 ways to solve other similar problems (like #3291).

-- 
Ticket URL: <https://trac.torproject.org/projects/tor/ticket/3302#comment:5>
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