[tor-bugs] #25552 [Core Tor/Tor]: prop224: Onion service rev counters are useless and actually harmful for scalability

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#25552: prop224: Onion service rev counters are useless and actually harmful for
scalability
-----------------------------------------------+---------------------------
 Reporter:  asn                                |          Owner:  dgoulet
     Type:  defect                             |         Status:
                                               |  needs_review
 Priority:  Medium                             |      Milestone:  Tor:
                                               |  0.3.4.x-final
Component:  Core Tor/Tor                       |        Version:  Tor:
                                               |  0.3.1.9
 Severity:  Normal                             |     Resolution:
 Keywords:  tor-hs prop224 034-roadmap-master  |  Actual Points:
Parent ID:                                     |         Points:  4
 Reviewer:  asn                                |        Sponsor:
-----------------------------------------------+---------------------------

Comment (by asn):

 Also see `bug25552_blinding` for an alternative design suggested by Nick,
 which blinds the `time(NULL)` timestamp with a hash derived from the
 ephemeral blinded key as such:
 {{{
     uint32_t BLINDING_FACTOR = SHA3(ephemeral_blinding_key)[4]
     uint64_t REV_COUNTER = now + BLINDING_FACTOR
 }}}

 IIUC, this offers the same properties as the OPE approach: monotonically
 increasing rev counter, with no state file needed, and with obfucated
 local time, but it requires time sync between load balancing nodes. It
 also seems easier to understand/review than the OPE approach.

 Nick what you think?

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Ticket URL: <https://trac.torproject.org/projects/tor/ticket/25552#comment:30>
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