[tor-bugs] #7570 [Tor]: Disable client-side DNS cacheing by default

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#7570: Disable client-side DNS cacheing by default
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 Reporter:  nickm                   |          Owner:                    
     Type:  enhancement             |         Status:  needs_review      
 Priority:  major                   |      Milestone:  Tor: 0.2.4.x-final
Component:  Tor                     |        Version:                    
 Keywords:  tor-client dns prop205  |         Parent:                    
   Points:                          |   Actualpoints:                    
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Comment(by andrea):

 This code all looks fine to me; go ahead and merge if you want.  I'm not
 sure I entirely understand why this linkability problem becomes worse with
 IPv6, though, so for my own enlightenment it'd be nice to hear about it at
 some point.

 Two tiny nitpicks:

  * make check-spaces says 'UnnecNL:src/or/relay.c:760'

  * The sentence "It's potentially risky to use cached DNS answers at the
 client can be risky for linkability, since doing so can indicate to one
 exit what answers we've gotten for DNS lookups in the past." in the
 changes file in commit 765606406b26d573242e1a1d759511751b279b21 should be
 taken out, shot and replaced with something that conforms with English
 grammar, or at least the Newspeak Dictionary, 9th Edition. :)

-- 
Ticket URL: <https://trac.torproject.org/projects/tor/ticket/7570#comment:3>
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