[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:  assigned
 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:                                     |        Sponsor:
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Comment (by dgoulet):

 Here is a fun fact. We use the revision counter in the computation of the
 descriptor encryption keys. See spec section `HS-DESC-ENCRYPTION-KEYS`.

 So bottom line, this means that we have to remove it from `secret_input`
 computation *but* only if we can't find the counter in the plaintext data
 of the descriptor (`"revision-counter" SP Integer NL`).

 Code wise, this isn't very complicated but I thought it would be wise to
 just throw it out there since it affects our crypto construction.

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Ticket URL: <https://trac.torproject.org/projects/tor/ticket/25552#comment:15>
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