[tor-bugs] #25903 [Core Tor/Tor]: Add PACKAGED and DELIVERED fields to CIRC_BW events

[Tor Bug Tracker & Wiki]

#25903: Add PACKAGED and DELIVERED fields to CIRC_BW events
------------------------------+----------------------------------
     Reporter:  mikeperry     |      Owner:  (none)
         Type:  defect        |     Status:  new
     Priority:  Medium        |  Milestone:
    Component:  Core Tor/Tor  |    Version:
     Severity:  Normal        |   Keywords:  034-roadmap-proposed
Actual Points:                |  Parent ID:  #25546
       Points:                |   Reviewer:
      Sponsor:                |
------------------------------+----------------------------------
 I want to have information about how much data is actually for
 applications, so that external controllers can check for circuit side
 channel attacks.

 To do this, I want to add two fields to CIRC_BW events: a PACKAGED field
 that reports the sum of all rh.length values for all relay cells, and a
 DELIVERED field that reports the sum of all rh.length for *valid*
 RELAY_DATA cells.

 That way, controllers can check for large differences between PACKAGED and
 DELIVERED, to see if lots of data is being sent on a circuit that is
 getting silently dropped. They can also check for differences between the
 raw CIRC_BW value and DELIVERED, to see if an adversary is underfilling
 cells (though this may be far more prone to false positives).

--
Ticket URL: <https://trac.torproject.org/projects/tor/ticket/25903>
Tor Bug Tracker & Wiki <https://trac.torproject.org/>
The Tor Project: anonymity online