[tor-bugs] #3652 [Tor Client]: Export clock skew opinion as getinfo command

Tor Bug Tracker & Wiki torproject-admin at torproject.org
Wed Aug 24 04:49:57 UTC 2011


#3652: Export clock skew opinion as getinfo command
-------------------------+--------------------------------------------------
 Reporter:  mikeperry    |          Owner:  nickm             
     Type:  enhancement  |         Status:  assigned          
 Priority:  major        |      Milestone:  Tor: 0.2.3.x-final
Component:  Tor Client   |        Version:                    
 Keywords:               |         Parent:                    
   Points:               |   Actualpoints:                    
-------------------------+--------------------------------------------------
Changes (by mikeperry):

  * owner:  => nickm
  * status:  needs_review => assigned


Comment:

 Replying to [comment:4 nickm]:
 > I started doing some work here in a branch called "skew_estimate".
 Needs some attention and review for sanity.

 In command_process_netinfo_cell(), why do you only set apparent_skew if
 conn->handshake_state->sent_versions_at was within 180 seconds? Is it
 possible that the dirauth just won't respond in any reasonable amount of
 time here?

 In connection_dir_client_reached_eof(), you use
 conn->_base.timestamp_lastwritten. Is there any way to obtain the
 timestamp of the first byte back from the request? If you can get that,
 you can then do 'delta = lastwritten + (firstbyte - lastwritten)/2 -
 date_header' to adjust for network+dirauth processing latency...

 In router_set_networkstatus_v2() and
 networkstatus_set_current_consensus(), you use the published/valid_after
 time. This is probably too low of a resolution to bother to record it to
 report for TBB. We care about precision down to the second (possibly even
 sub-second)... Recording this value will just cause all TBB users to all
 have weird, messed up clocks. If we want that property, we can get it
 other ways than through the control port command...

-- 
Ticket URL: <https://trac.torproject.org/projects/tor/ticket/3652#comment:6>
Tor Bug Tracker & Wiki <https://trac.torproject.org/>
The Tor Project: anonymity online


More information about the tor-bugs mailing list