Decouple Ipv6UpstreamRule with Ipv6DownstreamRule
Currently, Ipv6UpstreamRule is added follows the adding of
Ipv6DownstreamRule when it is the first rule from a downstream
interface to the upstream interface.
This CL changed it to:
1. Upstream interface change updates both IPv6 upstream and downstream
forwarding rules.
2. Neighbor events updates only IPv6 downstream forwarding rules.
Data limit setting on the upstream interface is now depend on the
upstream rules instead of the downstream rules. This CL also updates
corresponding test cases in IpServerTest and BpfCoordinatorTest.
Test: atest TetheringTests
Bug: 261923493
Change-Id: I5b4df64a3d276afb7a24bbef3a0432f53377e8b2
diff --git a/Tethering/src/android/net/ip/IpServer.java b/Tethering/src/android/net/ip/IpServer.java
index a851410..e030902 100644
--- a/Tethering/src/android/net/ip/IpServer.java
+++ b/Tethering/src/android/net/ip/IpServer.java
@@ -127,6 +127,7 @@
// TODO: have this configurable
private static final int DHCP_LEASE_TIME_SECS = 3600;
+ private static final int NO_UPSTREAM = 0;
private static final MacAddress NULL_MAC_ADDRESS = MacAddress.fromString("00:00:00:00:00:00");
private static final String TAG = "IpServer";
@@ -259,6 +260,12 @@
private int mLastError;
private int mServingMode;
private InterfaceSet mUpstreamIfaceSet; // may change over time
+ // mInterfaceParams can't be final now because IpServer will be created when receives
+ // WIFI_AP_STATE_CHANGED broadcasts or when it detects that the wifi interface has come up.
+ // In the latter case, the interface is not fully initialized and the MAC address might not
+ // be correct (it will be set with a randomized MAC address later).
+ // TODO: Consider create the IpServer only when tethering want to enable it, then we can
+ // make mInterfaceParams final.
private InterfaceParams mInterfaceParams;
// TODO: De-duplicate this with mLinkProperties above. Currently, these link
// properties are those selected by the IPv6TetheringCoordinator and relayed
@@ -740,7 +747,7 @@
RaParams params = null;
String upstreamIface = null;
InterfaceParams upstreamIfaceParams = null;
- int upstreamIfIndex = 0;
+ int upstreamIfIndex = NO_UPSTREAM;
if (v6only != null) {
upstreamIface = v6only.getInterfaceName();
@@ -772,7 +779,7 @@
// CMD_TETHER_CONNECTION_CHANGED. Adding the mapping update here to the avoid potential
// timing issue. It prevents that the IPv6 capability is updated later than
// CMD_TETHER_CONNECTION_CHANGED.
- mBpfCoordinator.addUpstreamNameToLookupTable(upstreamIfIndex, upstreamIface);
+ mBpfCoordinator.maybeAddUpstreamToLookupTable(upstreamIfIndex, upstreamIface);
// If v6only is null, we pass in null to setRaParams(), which handles
// deprecation of any existing RA data.
@@ -780,8 +787,7 @@
// Not support BPF on virtual upstream interface
final boolean upstreamSupportsBpf = upstreamIface != null && !isVcnInterface(upstreamIface);
- updateIpv6ForwardingRules(
- mLastIPv6UpstreamIfindex, upstreamIfIndex, upstreamSupportsBpf, null);
+ updateIpv6ForwardingRules(mLastIPv6UpstreamIfindex, upstreamIfIndex, upstreamSupportsBpf);
mLastIPv6LinkProperties = v6only;
mLastIPv6UpstreamIfindex = upstreamIfIndex;
mUpstreamSupportsBpf = upstreamSupportsBpf;
@@ -887,25 +893,23 @@
}
}
- // Handles all updates to IPv6 forwarding rules. These can currently change only if the upstream
- // changes or if a neighbor event is received.
+ private int getInterfaceIndexForRule(int ifindex, boolean supportsBpf) {
+ return supportsBpf ? ifindex : NO_UPSTREAM;
+ }
+
+ // Handles updates to IPv6 forwarding rules if the upstream changes.
private void updateIpv6ForwardingRules(int prevUpstreamIfindex, int upstreamIfindex,
- boolean upstreamSupportsBpf, NeighborEvent e) {
- // If no longer have an upstream or upstream not supports BPF, clear forwarding rules and do
- // nothing else.
- // TODO: Rather than always clear rules, ensure whether ipv6 ever enable first.
- if (upstreamIfindex == 0 || !upstreamSupportsBpf) {
- mBpfCoordinator.tetherOffloadRuleClear(this);
- return;
- }
-
+ boolean upstreamSupportsBpf) {
// If the upstream interface has changed, remove all rules and re-add them with the new
- // upstream interface.
+ // upstream interface. If upstream is a virtual network, treated as no upstream.
if (prevUpstreamIfindex != upstreamIfindex) {
- mBpfCoordinator.tetherOffloadRuleUpdate(this, upstreamIfindex);
+ mBpfCoordinator.updateAllIpv6Rules(this, this.mInterfaceParams,
+ getInterfaceIndexForRule(upstreamIfindex, upstreamSupportsBpf));
}
+ }
- // If we're here to process a NeighborEvent, do so now.
+ // Handles updates to IPv6 downstream rules if a neighbor event is received.
+ private void addOrRemoveIpv6Downstream(NeighborEvent e) {
// mInterfaceParams must be non-null or the event would not have arrived.
if (e == null) return;
if (!(e.ip instanceof Inet6Address) || e.ip.isMulticastAddress()
@@ -917,8 +921,9 @@
// Do this here instead of in the Ipv6DownstreamRule constructor to ensure that we
// never add rules with a null MAC, only delete them.
MacAddress dstMac = e.isValid() ? e.macAddr : NULL_MAC_ADDRESS;
- Ipv6DownstreamRule rule = new Ipv6DownstreamRule(upstreamIfindex, mInterfaceParams.index,
- (Inet6Address) e.ip, mInterfaceParams.macAddr, dstMac);
+ Ipv6DownstreamRule rule = new Ipv6DownstreamRule(
+ getInterfaceIndexForRule(mLastIPv6UpstreamIfindex, mUpstreamSupportsBpf),
+ mInterfaceParams.index, (Inet6Address) e.ip, mInterfaceParams.macAddr, dstMac);
if (e.isValid()) {
mBpfCoordinator.addIpv6DownstreamRule(this, rule);
} else {
@@ -951,8 +956,7 @@
if (mInterfaceParams != null
&& mInterfaceParams.index == e.ifindex
&& mInterfaceParams.hasMacAddress) {
- updateIpv6ForwardingRules(mLastIPv6UpstreamIfindex, mLastIPv6UpstreamIfindex,
- mUpstreamSupportsBpf, e);
+ addOrRemoveIpv6Downstream(e);
updateClientInfoIpv4(e);
}
}
@@ -1285,6 +1289,7 @@
@Override
public void exit() {
cleanupUpstream();
+ mBpfCoordinator.clearAllIpv6Rules(IpServer.this);
super.exit();
}
@@ -1303,7 +1308,8 @@
for (String ifname : mUpstreamIfaceSet.ifnames) cleanupUpstreamInterface(ifname);
mUpstreamIfaceSet = null;
- mBpfCoordinator.tetherOffloadRuleClear(IpServer.this);
+ mBpfCoordinator.updateAllIpv6Rules(
+ IpServer.this, IpServer.this.mInterfaceParams, NO_UPSTREAM);
}
private void cleanupUpstreamInterface(String upstreamIface) {
@@ -1370,7 +1376,7 @@
final InterfaceParams upstreamIfaceParams =
mDeps.getInterfaceParams(ifname);
if (upstreamIfaceParams != null) {
- mBpfCoordinator.addUpstreamNameToLookupTable(
+ mBpfCoordinator.maybeAddUpstreamToLookupTable(
upstreamIfaceParams.index, ifname);
}
}
@@ -1430,6 +1436,8 @@
class UnavailableState extends State {
@Override
public void enter() {
+ // TODO: move mIpNeighborMonitor.stop() to TetheredState#exit, and trigger a neighbours
+ // dump after starting mIpNeighborMonitor.
mIpNeighborMonitor.stop();
mLastError = TETHER_ERROR_NO_ERROR;
sendInterfaceState(STATE_UNAVAILABLE);