[tor-bugs] #29130 [Core Tor/Tor]: Work out how to handle multiple reports from the same relay in PrivCount

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#29130: Work out how to handle multiple reports from the same relay in PrivCount
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     Reporter:  teor          |      Owner:  (none)
         Type:  defect        |     Status:  new
     Priority:  Medium        |  Milestone:  Tor: unspecified
    Component:  Core Tor/Tor  |    Version:
     Severity:  Normal        |   Keywords:  041-proposed
Actual Points:                |  Parent ID:  #22898
       Points:  2             |   Reviewer:
      Sponsor:                |
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 What do we do in PrivCount if the same relay reports twice?

 This can happen if:
 * multiple relays share the same keys, or
 * a relay forgets that it has reported, so it reports again

 We need a way for the tally reporters to check if they have consistent
 data from each relay.

 We could do a validation round, where we check that ZeroCount is 0, and
 RelayCount is 1. These values are constants, so the validation round has
 no privacy implications.

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Ticket URL: <https://trac.torproject.org/projects/tor/ticket/29130>
Tor Bug Tracker & Wiki <https://trac.torproject.org/>
The Tor Project: anonymity online