diff --git a/services/net/java/android/net/ip/IpManager.java b/services/net/java/android/net/ip/IpManager.java index 654ef18f9608f..6d9020390bef2 100644 --- a/services/net/java/android/net/ip/IpManager.java +++ b/services/net/java/android/net/ip/IpManager.java @@ -382,6 +382,7 @@ public class IpManager extends StateMachine { private final State mStoppedState = new StoppedState(); private final State mStoppingState = new StoppingState(); private final State mStartedState = new StartedState(); + private final State mRunningState = new RunningState(); private final String mTag; private final Context mContext; @@ -476,6 +477,7 @@ public class IpManager extends StateMachine { // Super simple StateMachine. addState(mStoppedState); addState(mStartedState); + addState(mRunningState, mStartedState); addState(mStoppingState); setInitialState(mStoppedState); @@ -570,7 +572,7 @@ public class IpManager extends StateMachine { pw.decreaseIndent(); pw.println(); - pw.println("StateMachine dump:"); + pw.println(mTag + " StateMachine dump:"); pw.increaseIndent(); mLocalLog.readOnlyLocalLog().dump(fd, pw, args); pw.decreaseIndent(); @@ -768,6 +770,11 @@ public class IpManager extends StateMachine { // - IPv6 addresses // - IPv6 routes // - IPv6 DNS servers + // + // N.B.: this is fundamentally race-prone and should be fixed by + // changing NetlinkTracker from a hybrid edge/level model to an + // edge-only model, or by giving IpManager its own netlink socket(s) + // so as to track all required information directly. LinkProperties netlinkLinkProperties = mNetlinkTracker.getLinkProperties(); newLp.setLinkAddresses(netlinkLinkProperties.getLinkAddresses()); for (RouteInfo route : netlinkLinkProperties.getRoutes()) { @@ -939,16 +946,30 @@ public class IpManager extends StateMachine { return true; } + private void stopAllIP() { + // We don't need to worry about routes, just addresses, because: + // - disableIpv6() will clear autoconf IPv6 routes as well, and + // - we don't get IPv4 routes from netlink + // so we neither react to nor need to wait for changes in either. + + try { + mNwService.disableIpv6(mInterfaceName); + } catch (Exception e) { + Log.e(mTag, "Failed to disable IPv6" + e); + } + + try { + mNwService.clearInterfaceAddresses(mInterfaceName); + } catch (Exception e) { + Log.e(mTag, "Failed to clear addresses " + e); + } + } + class StoppedState extends State { @Override public void enter() { - try { - mNwService.disableIpv6(mInterfaceName); - mNwService.clearInterfaceAddresses(mInterfaceName); - } catch (Exception e) { - Log.e(mTag, "Failed to clear addresses or disable IPv6" + e); - } + stopAllIP(); resetLinkProperties(); if (mStartTimeMillis > 0) { @@ -1023,12 +1044,71 @@ public class IpManager extends StateMachine { } class StartedState extends State { - private boolean mDhcpActionInFlight; - @Override public void enter() { mStartTimeMillis = SystemClock.elapsedRealtime(); + if (mConfiguration.mProvisioningTimeoutMs > 0) { + final long alarmTime = SystemClock.elapsedRealtime() + + mConfiguration.mProvisioningTimeoutMs; + mProvisioningTimeoutAlarm.schedule(alarmTime); + } + + if (readyToProceed()) { + transitionTo(mRunningState); + } else { + // Clear all IPv4 and IPv6 before proceeding to RunningState. + // Clean up any leftover state from an abnormal exit from + // tethering or during an IpManager restart. + stopAllIP(); + } + } + + @Override + public void exit() { + mProvisioningTimeoutAlarm.cancel(); + } + + @Override + public boolean processMessage(Message msg) { + switch (msg.what) { + case CMD_STOP: + transitionTo(mStoppingState); + break; + + case EVENT_NETLINK_LINKPROPERTIES_CHANGED: + handleLinkPropertiesUpdate(NO_CALLBACKS); + if (readyToProceed()) { + transitionTo(mRunningState); + } + break; + + case EVENT_PROVISIONING_TIMEOUT: + handleProvisioningFailure(); + break; + + default: + // It's safe to process messages out of order because the + // only message that can both + // a) be received at this time and + // b) affect provisioning state + // is EVENT_NETLINK_LINKPROPERTIES_CHANGED (handled above). + deferMessage(msg); + } + return HANDLED; + } + + boolean readyToProceed() { + return (!mLinkProperties.hasIPv4Address() && + !mLinkProperties.hasGlobalIPv6Address()); + } + } + + class RunningState extends State { + private boolean mDhcpActionInFlight; + + @Override + public void enter() { mApfFilter = ApfFilter.maybeCreate(mConfiguration.mApfCapabilities, mNetworkInterface, mCallback, mMulticastFiltering); // TODO: investigate the effects of any multicast filtering racing/interfering with the @@ -1037,12 +1117,6 @@ public class IpManager extends StateMachine { mCallback.setFallbackMulticastFilter(mMulticastFiltering); } - if (mConfiguration.mProvisioningTimeoutMs > 0) { - final long alarmTime = SystemClock.elapsedRealtime() + - mConfiguration.mProvisioningTimeoutMs; - mProvisioningTimeoutAlarm.schedule(alarmTime); - } - if (mConfiguration.mEnableIPv6) { // TODO: Consider transitionTo(mStoppingState) if this fails. startIPv6(); @@ -1070,7 +1144,6 @@ public class IpManager extends StateMachine { @Override public void exit() { - mProvisioningTimeoutAlarm.cancel(); stopDhcpAction(); if (mIpReachabilityMonitor != null) { @@ -1167,10 +1240,6 @@ public class IpManager extends StateMachine { break; } - case EVENT_PROVISIONING_TIMEOUT: - handleProvisioningFailure(); - break; - case EVENT_DHCPACTION_TIMEOUT: stopDhcpAction(); break;