[tor-bugs] #32020 [Core Tor/Tor]: hsv3: Client do not report failing circuit back into HS subsystem

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#32020: hsv3: Client do not report failing circuit back into HS subsystem
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 Reporter:  dgoulet             |          Owner:  dgoulet
     Type:  defect              |         Status:  needs_review
 Priority:  Medium              |      Milestone:  Tor: 0.4.3.x-final
Component:  Core Tor/Tor        |        Version:
 Severity:  Normal              |     Resolution:
 Keywords:  tor-hs, tor-client  |  Actual Points:  1
Parent ID:  #30200              |         Points:  1
 Reviewer:  asn                 |        Sponsor:  Sponsor27-must
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Comment (by asn):

 Replying to [comment:3 dgoulet]:
 > Related is #26806 which mentions that possibly because the HSv3 client
 is not noticing the introduction timeout (as in the ACK never came back),
 we resend onto that same intro point. Good or bad?


 Hmm, questions and answers:

 1) Why doesn't the ACK or NACK come to the client? Is it because the intro
   point never sent it (why?)? Or because we timeout before receiving it?
 Or just
   general Tor network SNAFU?

 2) If the above happens, why would the client decide to resend on the same
   intro point and same circuit? Is this an explicit decision?

 3) Regarding "Good or bad?" I would say it's bad-ish because if the NACK
 never
   came back, I would prefer to retry a different intro point since that
 one
   might be suffering networking issues, or being overloaded, or downright
   maliciously DoSing the service.

 PS: #26806 mentions "rendezvous circuits" in the title, but I think it
 should be intro circuits

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Ticket URL: <https://trac.torproject.org/projects/tor/ticket/32020#comment:5>
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