commit db6befbd17ab133e47c95c870160e0f317516d89
author Mark Chien <markchien@google.com> Fri May 29 22:07:37 2020 +0000
committer Mark Chien <markchien@google.com> Sat May 30 03:42:57 2020 +0000
tree 428897f4afbd806d6d5b7428750f8b3db0ee7994
parent 7d4bad92af39bee1afcc0bb13d3c62f671ce2cc9

Tethering: ensure downstream prefix do not conflict with upstream

- Add New class PrivateAddressCoordinator to coordinate the private
  address conflict problem.
- Downstream prefix would be random in 192.168.0.0/24 ~
  192.168.255.0/24.
- If new upstream prefix is conflict with existing downstream prefix,
  downstream would be kicked out and it would request a new one.
- The last conflict upstream prefixes would be blacklist. Avoid to
select downstream prefix which is conflict with prefixes in blacklist.

Bug: 130879722
Test: -build, flash, boot
      -atest TetheringTests

Merged-In: Ib45b87bcd9eeb5da03fb7ec90b1af9ca53998cf5
Change-Id: Ib45b87bcd9eeb5da03fb7ec90b1af9ca53998cf5