[tor-bugs] #32088 [Core Tor/Tor]: Proposal 308 - choose guards in sampled order

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#32088: Proposal 308 - choose guards in sampled order
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 Reporter:  Jaym                      |          Owner:  (none)
     Type:  enhancement               |         Status:  needs_revision
 Priority:  Medium                    |      Milestone:  Tor: 0.4.4.x-final
Component:  Core Tor/Tor              |        Version:
 Severity:  Normal                    |     Resolution:
 Keywords:  tor-spec prop271 prop308  |  Actual Points:
Parent ID:                            |         Points:
 Reviewer:  nickm                     |        Sponsor:
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Comment (by Jaym):

 Hello,

 The pull request has been updated.

 On loading, Tor sets the sampled_idx to the confirmed_idx. That should
 keep older clients to behave the same (and not reordering primary guards).
 On the next state save, the sampled_idx should be made dense.

 Also, the patch applies now ordering when it seems necessary (a couple of
 redundant orderings have been removed).

 Also, I was concerned by the fact that Tor assumes integrity of the state
 when loading it. If some application has write access to this file, making
 the client rotate guards until a chosen one is found shouldn't be too much
 of a hard task. Is that kind of threat relevant?

--
Ticket URL: <https://trac.torproject.org/projects/tor/ticket/32088#comment:14>
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