[tor-bugs] #10082 [Flashproxy]: flashproxy-client fails to communicate with connected browser proxies when logging is disabled

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#10082: flashproxy-client fails to communicate with connected browser proxies when
logging is disabled
------------------------+---------------------
 Reporter:  infinity0   |          Owner:  dcf
     Type:  defect      |         Status:  new
 Priority:  major       |      Milestone:
Component:  Flashproxy  |        Version:
 Keywords:              |  Actual Points:
Parent ID:              |         Points:
------------------------+---------------------
 This is reproducible 100% of the time on my Windows XP machine, both with
 plain flashproxy and obfs-flash-client. In all cases, Process Explorer
 shows that flashproxy-client.exe has several established incoming TCP
 connections on port 9000.

 Failing cases:

 {{{
 Bridge flashproxy 127.0.0.1:9001
 ClientTransportPlugin flashproxy exec App\flashproxy-client --register
 127.0.0.1:9001 :9000
 }}}

 {{{
 Bridge obfs3_flashproxy 127.0.0.1:2334
 ClientTransportPlugin obfs3_flashproxy exec App\obfs-flash-client --fp-
 arg=--register 2334 :9000
 }}}

 Here, Vidalia hangs on "Establishing an encrypted directory connection".
 The Tor message log sometimes hangs at "Bootstrapped 10%: Finishing
 handshake with directory server" and sometimes at "Bootstrapped 15%:
 Establishing an encrypted directory connection", then eventually fails
 with "1 connections died in state handshaking (TLS) with SSLv2/v3 read
 server hello A in HANDSHAKE" or "... with SSL state SSLv3 read finished A
 in HANDSHAKE".

 Success cases (removing `--unsafe-logging` has the same effect):

 {{{
 Bridge flashproxy 127.0.0.1:9001
 ClientTransportPlugin flashproxy exec App\flashproxy-client --register -l
 flashproxy.log 127.0.0.1:9001 :9000
 }}}

 {{{
 Bridge obfs3_flashproxy 127.0.0.1:2334
 ClientTransportPlugin obfs3_flashproxy exec App\obfs-flash-client --fp-
 arg=--register --fp-arg=-l --fp-arg=flashproxy.log 2334 :9000
 }}}

 This is probably some Python buffering issue. I am going to try to build
 flashproxy-client with py2exe's unbuffered IO option and see what happens.
 Possibly also try replacing cases of readlines() into a while True:
 readline() loop (as `man python`, section `-u` suggests).

 I am testing using the PTBB I built myself here:
 https://people.torproject.org/~infinity0/bin/ I built this on WINE, but
 I've also dropped into it a flashproxy-client.exe / py2exe-flashproxy.zip
 built directly on the Windows XP machine I am using, and it shows the same
 behaviour. In both cases I am using flashproxy from
 [https://github.com/infinity0/flashproxy/commit/b9baa31cda3b788fb39e68a1af91a6d9a6939855
 commit b9baa31c from my github].

-- 
Ticket URL: <https://trac.torproject.org/projects/tor/ticket/10082>
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