[tor-bugs] #11100 [Obfsproxy]: ScrambleSuit session ticket handshake failures

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#11100: ScrambleSuit session ticket handshake failures
---------------------------+-----------------------------------------
     Reporter:  yawning    |      Owner:  phw
         Type:  defect     |     Status:  new
     Priority:  normal     |  Milestone:
    Component:  Obfsproxy  |    Version:
   Resolution:             |   Keywords:  ScrambleSuit, SessionTicket
Actual Points:             |  Parent ID:
       Points:             |
---------------------------+-----------------------------------------

Comment (by yawning):

 Got another bridge to test with, and I can consistently reproduce this, so
 it's not bridge specific.

 {{{
 2014-03-01 08:21:24,944 [DEBUG] Message header: totalLen=144,
 payloadLen=144, flags=NEW_TICKET
 2014-03-01 08:21:24,944 [DEBUG] Storing newly received ticket in
 `/home/yawning/.tor/pt_state/scramblesuit/session_ticket.yaml'.

 [I close after bootstrapping, and go read for a while, come back some time
 later.]

 2014-03-01 09:19:58,402 [DEBUG] Attempting to read master key and ticket
 from file `/home/yawning/.tor/pt_state/scramblesuit/session_ticket.yaml'.
 2014-03-01 09:19:58,402 [DEBUG] Opening
 `/home/yawning/.tor/pt_state/scramblesuit/session_ticket.yaml' for
 reading.
 2014-03-01 09:19:58,405 [DEBUG] Deleting ticket since it is about to be
 redeemed.
 2014-03-01 09:19:58,405 [DEBUG] Opening
 `/home/yawning/.tor/pt_state/scramblesuit/session_ticket.yaml' for
 writing.
 2014-03-01 09:19:58,405 [DEBUG] Redeeming stored session ticket.

 [snip, Session key derivation is uninteresting]

 2014-03-01 09:19:58,406 [DEBUG] Switching to state ST_CONNECTED.
 2014-03-01 09:19:58,406 [DEBUG] Send buffer is empty; nothing to flush.
 2014-03-01 09:19:58,406 [DEBUG] circ_0x2491c20: upstream: Received 265
 bytes.
 2014-03-01 09:19:58,406 [DEBUG] Processing 265 bytes of outgoing data.
 2014-03-01 09:19:58,407 [DEBUG] Created 1 protocol messages.
 2014-03-01 09:19:58,407 [DEBUG] Morphing the last 286-byte packet to 279
 bytes by adding 1441 bytes of padding.
 2014-03-01 09:19:58,416 [DEBUG] socks_down_0x248cf10: Received 0 bytes.
 2014-03-01 09:19:58,417 [DEBUG] circ_0x2491c20: downstream: Received 0
 bytes.

 [Tor gives up]

 Mar 01 09:19:58.000 [notice] Bootstrapped 10%: Finishing handshake with
 directory server.
 Mar 01 09:24:58.000 [warn] Problem bootstrapping. Stuck at 10%: Finishing
 handshake with directory server. (DONE; DONE; count 1; recommendation
 warn)
 Mar 01 09:24:58.000 [warn] 1 connections have failed:
 Mar 01 09:24:58.000 [warn]  1 connections died in state handshaking (TLS)
 with SSL state SSLv2/v3 read server hello A in HANDSHAKE
 }}}

 I'll keep trying to reproduce it locally.

--
Ticket URL: <https://trac.torproject.org/projects/tor/ticket/11100#comment:1>
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