[tor-bugs] #26980 [Core Tor/Tor]: HSv3 descriptors rejected because of bad SRV start time computation

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#26980: HSv3 descriptors rejected because of bad SRV start time computation
-----------------------------+---------------------------------------------
     Reporter:  asn          |      Owner:  (none)
         Type:  defect       |     Status:  new
     Priority:  Medium       |  Milestone:  Tor: 0.3.5.x-final
    Component:  Core         |    Version:
  Tor/Tor                    |
     Severity:  Normal       |   Keywords:  035-must regression tor-hs hsv3
Actual Points:               |  Parent ID:
       Points:               |   Reviewer:
      Sponsor:               |
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 When we introduced #25552, we started OPE encrypting the time diff since
 the start of the SRV run. We also have some logic on which SRV period we
 should use to calculate the time diff:
 {{{
   if (is_current) {
     srv_start = sr_state_get_start_time_of_previous_protocol_run();
   } else {
     srv_start = sr_state_get_start_time_of_current_protocol_run();
   }
 }}}

 There is a bug here, because when we cross from the 23:00 consensus to the
 00:00 consensus (or the 01:00 one), the start of the SRV protocol changes
 and screws up the revision counter monotonicity.

 This causes one descriptor batch upload to fail.

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Ticket URL: <https://trac.torproject.org/projects/tor/ticket/26980>
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