tree 23571cd8e90ecde4ae73f06181aeb6af56ce8973
parent 9be367afbaa37bdf0f5fdca9a63eeae9647f7fbf
author Bjoern Johansson <bjoernj@google.com> 1535067833 -0700
committer Roman Kiryanov <rkir@google.com> 1538676913 -0700

Improve IPv6 networking for radio

RIL only announced addresses supplied by the emulator host. For IPv6 the
guest uses Neighbor Discovery Protocol to determine which IPv6 addresses
to assign to an interface and what gateway to use. This was not
reflected in RIL though which meant that the Android framework was
unaware of the radio using these addresses. There are now CTS tests that
rely on the framework knowing which addresses are assigned to verify
that connections to external servers are made from the correct
interface. These tests would fail on the radio interface.

In addition to providing interface addresses RIL also provides DNS
servers. It would only provide whatever DNS servers the DHCP client
could find. On networks that are configured to use IPv6 DNS servers this
left the radio interface without any usable DNS servers.

This change adds an interface monitor to the RIL that is looking for
address changes on the radio network interface. It then sends updates to
the framework whenever the addresses change. And to solve the specific
IPv6 problem it looks at IPv6 addreses. RIL still expects the IPv4
address to either be hardcoded for the Wifi case or supplied by the
emulator host if the Wifi feature is not enabled.

To fix the IPv6 DNS server issue the ipv6proxy will now inspect each
incoming Router Advertisement packet and extract any IPv6 DNS servers
provided in those packets. The proxy will set a system property for each
extracted DNS server. The RIL will then take the value from these system
properties and use in its messages to the framework, indicating which
DNS servers to use.

Test: run cts -m CtsNetTestCases -t
android.net.cts.ConnectivityManagerTest#testOpenConnection
BUG: 111691186
Merged-In: Ia970d2dda18c2615cacca496701c67f2066530a7
(cherry picked from commit 6ef3b9b3299bef6f3cc57c5d0933f846ee98f277)