[tor-bugs] #31490 [Core Tor/Tor]: hs-v3: Turns out the hs_ident circuit_type is not used

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#31490: hs-v3: Turns out the hs_ident circuit_type is not used
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     Reporter:  dgoulet        |      Owner:  (none)
         Type:  defect         |     Status:  new
     Priority:  Medium         |  Milestone:  Tor: 0.4.3.x-final
    Component:  Core Tor/Tor   |    Version:
     Severity:  Normal         |   Keywords:  tor-hs
Actual Points:                 |  Parent ID:
       Points:                 |   Reviewer:
      Sponsor:  Sponsor27-can  |
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 I stumble upon this while investigating #30200. My HS debugging showed up
 with circuit type set to `INTRO` for a rendezvous circuit.

 In, one of the most insane function we have,
 `circuit_get_open_circ_or_launch()`, towards the end, we set the HS
 identifier of the open circuit:

 {{{
           circ->hs_ident =
             hs_ident_circuit_new(&edge_conn->hs_ident->identity_pk,
                                  HS_IDENT_CIRCUIT_INTRO);
 }}}

 ... notice, we only use INTRO type, never the RENDEZVOUS one.

 Further looking at it, it appears that the `hs_ident->circuit_type` field
 is just pointless. Client will only set the INTRO (see code above) and the
 service will properly set both. But then after that, it is just never
 used.

 I propose we either remove it or fix the client side because if we ever
 rely on that field, it is of today really wrong client side.

--
Ticket URL: <https://trac.torproject.org/projects/tor/ticket/31490>
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