[tor-bugs] #9229 [Obfsproxy]: While bootstrapping, Tor clients stall for 60s when obfsproxy bridges are used.

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#9229: While bootstrapping, Tor clients stall for 60s when obfsproxy bridges are
used.
----------------------------------------------+-----------------------------
 Reporter:  phw                               |          Owner:  asn
     Type:  defect                            |         Status:  new
 Priority:  normal                            |      Milestone:     
Component:  Obfsproxy                         |        Version:     
 Keywords:  60s, consensus, stall, obfsproxy  |         Parent:     
   Points:                                    |   Actualpoints:     
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 When Tor bootstraps using obfsproxy, it stalls for 60 seconds. The last
 three log messages before that happening are:

 {{{
 [notice] Bootstrapped 50%: Loading relay descriptors.
 [notice] new bridge descriptor 'bzoum' (fresh):
 $2ADFE7AA8D272C520D1FBFBF4E413F3A1B26313D~bzoum at [redacted]
 [notice] I learned some more directory information, but not enough to
 build a circuit: We have no usable consensus.
 }}}
 After 60 seconds, it continues to bootstrap to 100%. This was observed for
 all pluggable transports: flash proxies, obfs{2,3} and ScrambleSuit.
 Vanilla bridges do '''not''' seem to be affected by this. Also, the
 '''very first''' bootstrap (i.e., with an empty data directory) also seems
 to be unaffected by this.

 I attached two files containing debug logs (after the second bootstrap) of
 obfs3 and vanilla bridges. I removed the timestamps to make it easy to
 compare both of them.

 I tested this with Tor v0.2.4.15-rc and obfsproxy
 da31ffc638a2727df1679bc888c2a8c1c49809a9.

-- 
Ticket URL: <https://trac.torproject.org/projects/tor/ticket/9229>
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