[tor-bugs] #17027 [Tor]: policies_parse_exit_policy_internal should block all IPv4 and IPv6 local addresses

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#17027: policies_parse_exit_policy_internal should block all IPv4 and IPv6 local
addresses
-------------------------+-------------------------------------------------
     Reporter:  teor     |      Owner:
         Type:  defect   |     Status:  new
     Priority:  major    |  Milestone:  Tor: 0.2.7.x-final
    Component:  Tor      |    Version:  Tor: unspecified
   Resolution:           |   Keywords:  TorCoreTeam201509 security
Actual Points:           |  026-backport
       Points:           |  Parent ID:
-------------------------+-------------------------------------------------
Changes (by teor):

 * version:  Tor: 0.2.7.2-alpha => Tor: unspecified


Comment:

 Further notes:

 This is a patch on 42b8fb5a1523 (11 Nov 2007), released in 0.2.0.11-alpha.

 This fix will automatically benefit from changes that find more
 interfaces/addresses, perhaps #12377 will do this for some platforms.

 We should log an info-level (notice?) message for each address blocked
 Internal addresses are blocked anyway by `reject private *:*`, so this
 patch doesn't need to block them.

 This change will include all addresses in non-internal blocks in the
 publicly available exit policy, but these addresses are typically globally
 visible on the Internet anyway. I believe the security benefits outweigh
 the small risk of leaking public server addresses from unusual
 configurations (and operators can always set `ExitPolicyRejectPrivate 0`
 and block only the private and server addresses they want to block).

--
Ticket URL: <https://trac.torproject.org/projects/tor/ticket/17027#comment:5>
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