tag 9c022327aed75384e288a5a90edb436d106eab1c
tagger The Android Open Source Project <initial-contribution@android.com> Tue Dec 02 16:50:44 2014 -0800
object 0ec5dfa1da6a97532dc8cca825bae4edfb7d3dce

Android 5.0.1 release 1

commit 0ec5dfa1da6a97532dc8cca825bae4edfb7d3dce
author Erik Kline <ek@google.com> Mon Sep 22 13:32:27 2014 +0900
committer Erik Kline <ek@google.com> Wed Sep 24 16:02:31 2014 +0900
tree 34185fdc8520137e7aaa4e711f4f6bf4511da514
parent dce3ddf54083ccd0e3752c4c08013688f79baa7a

Simplify and always retry DNS64 prefix discovery.

  - Only request AAAAs for the IPv4-only hostname, since that's
    all the information being used.  Perhaps at some point in the
    future when _validation_ of the IPv4 address(es)'s presence
    within the IPv6 address(es) is being done this should be
    revisited.

  - Only use the first AAAA returned to find the DNS64 prefix.
    It's not clear how to properly resolve any potential DNS64
    prefix conflicts anyway.

  - Re-try DNS64 prefix discovery on any type of error.
    If clatd was started (presumably an IPv6-only network), retry
    DNS64 prefix discovery with exponential backoff.  Some
    "permanent" errors can be indistinguishable from transient
    errors (e.g. receiving an erroneous SERVFAIL from a DNS
    resolver, ...).

  - Fix-up back-off logic to not sleep 128 then 120, 120, ...
    :-)

Bug: 17569702
Change-Id: I226ea7772cd7c88d2b60153ef76e5435400e11aa