Extract TetherInterfaceSM to its own class. (d2896669) · Commits · e / os / android_frameworks_base

services/core/java/com/android/server/connectivity/Tethering.java

+1 −439

Original line number	Diff line number	Diff line
		@@ -71,6 +71,7 @@ import com.android.internal.util.State;
		import com.android.internal.util.StateMachine;
		import com.android.server.IoThread;
		import com.android.server.connectivity.tethering.IControlsTethering;
		import com.android.server.connectivity.tethering.TetherInterfaceSM;
		import com.android.server.net.BaseNetworkObserver;

		import java.io.FileDescriptor;
		@@ -135,9 +136,6 @@ public class Tethering extends BaseNetworkObserver implements IControlsTethering
		private static final ComponentName TETHER_SERVICE = ComponentName.unflattenFromString(Resources
		.getSystem().getString(com.android.internal.R.string.config_wifi_tether_enable));

		private static final String USB_NEAR_IFACE_ADDR = "192.168.42.129";
		private static final int USB_PREFIX_LENGTH = 24;

		// USB is 192.168.42.1 and 255.255.255.0
		// Wifi is 192.168.43.1 and 255.255.255.0
		// BT is limited to max default of 5 connections. 192.168.44.1 to 192.168.48.1
		@@ -980,442 +978,6 @@ public class Tethering extends BaseNetworkObserver implements IControlsTethering
		}
		}

		/**
		* @hide
		*
		* Tracks the eligibility of a given network interface for tethering.
		*/
		public static class TetherInterfaceSM extends StateMachine {
		private static final int BASE_IFACE = Protocol.BASE_TETHERING + 100;
		// notification from the master SM that it's not in tether mode
		static final int CMD_TETHER_MODE_DEAD = BASE_IFACE + 1;
		// request from the user that it wants to tether
		static final int CMD_TETHER_REQUESTED = BASE_IFACE + 2;
		// request from the user that it wants to untether
		static final int CMD_TETHER_UNREQUESTED = BASE_IFACE + 3;
		// notification that this interface is down
		static final int CMD_INTERFACE_DOWN = BASE_IFACE + 4;
		// notification that this interface is up
		static final int CMD_INTERFACE_UP = BASE_IFACE + 5;
		// notification from the master SM that it had an error turning on cellular dun
		static final int CMD_CELL_DUN_ERROR = BASE_IFACE + 6;
		// notification from the master SM that it had trouble enabling IP Forwarding
		static final int CMD_IP_FORWARDING_ENABLE_ERROR = BASE_IFACE + 7;
		// notification from the master SM that it had trouble disabling IP Forwarding
		static final int CMD_IP_FORWARDING_DISABLE_ERROR = BASE_IFACE + 8;
		// notification from the master SM that it had trouble starting tethering
		static final int CMD_START_TETHERING_ERROR = BASE_IFACE + 9;
		// notification from the master SM that it had trouble stopping tethering
		static final int CMD_STOP_TETHERING_ERROR = BASE_IFACE + 10;
		// notification from the master SM that it had trouble setting the DNS forwarders
		static final int CMD_SET_DNS_FORWARDERS_ERROR = BASE_IFACE + 11;
		// the upstream connection has changed
		static final int CMD_TETHER_CONNECTION_CHANGED = BASE_IFACE + 12;

		private final State mInitialState;
		private final State mStartingState;
		private final State mTetheredState;
		private final State mUnavailableState;

		private final INetworkManagementService mNMService;
		private final INetworkStatsService mStatsService;
		private final IControlsTethering mTetherController;

		private final boolean mUsb;
		private final String mIfaceName;

		private final Object mMutex; // Protects the fields below.
		private boolean mAvailable;
		private boolean mTethered;
		private int mLastError;
		private String mMyUpstreamIfaceName; // may change over time

		TetherInterfaceSM(String ifaceName, Looper looper, boolean usb, Object mutex,
		INetworkManagementService nMService, INetworkStatsService statsService,
		IControlsTethering tetherController) {
		super(ifaceName, looper);
		mNMService = nMService;
		mStatsService = statsService;
		mTetherController = tetherController;
		mIfaceName = ifaceName;
		mUsb = usb;
		mMutex = mutex;
		setLastError(ConnectivityManager.TETHER_ERROR_NO_ERROR);

		mInitialState = new InitialState();
		addState(mInitialState);
		mStartingState = new StartingState();
		addState(mStartingState);
		mTetheredState = new TetheredState();
		addState(mTetheredState);
		mUnavailableState = new UnavailableState();
		addState(mUnavailableState);

		setInitialState(mInitialState);
		}

		@Override
		public String toString() {
		String res = new String();
		res += mIfaceName + " - ";
		IState current = getCurrentState();
		if (current == mInitialState) res += "InitialState";
		if (current == mStartingState) res += "StartingState";
		if (current == mTetheredState) res += "TetheredState";
		if (current == mUnavailableState) res += "UnavailableState";
		if (isAvailable()) res += " - Available";
		if (isTethered()) res += " - Tethered";
		res += " - lastError =" + getLastError();
		return res;
		}

		public int getLastError() {
		synchronized (mMutex) {
		return mLastError;
		}
		}

		private void setLastError(int error) {
		synchronized (mMutex) {
		mLastError = error;

		if (isErrored()) {
		if (mUsb) {
		// note everything's been unwound by this point so nothing to do on
		// further error..
		configureUsbIface(false, mIfaceName);
		}
		}
		}
		}

		public boolean isAvailable() {
		synchronized (mMutex) {
		return mAvailable;
		}
		}

		private void setAvailable(boolean available) {
		synchronized (mMutex) {
		mAvailable = available;
		}
		}

		public boolean isTethered() {
		synchronized (mMutex) {
		return mTethered;
		}
		}

		private void setTethered(boolean tethered) {
		synchronized (mMutex) {
		mTethered = tethered;
		}
		}

		public boolean isErrored() {
		synchronized (mMutex) {
		return (mLastError != ConnectivityManager.TETHER_ERROR_NO_ERROR);
		}
		}

		// configured when we start tethering and unconfig'd on error or conclusion
		private boolean configureUsbIface(boolean enabled, String iface) {
		if (VDBG) Log.d(TAG, "configureUsbIface(" + enabled + ")");

		InterfaceConfiguration ifcg = null;
		try {
		ifcg = mNMService.getInterfaceConfig(iface);
		if (ifcg != null) {
		InetAddress addr = NetworkUtils.numericToInetAddress(USB_NEAR_IFACE_ADDR);
		ifcg.setLinkAddress(new LinkAddress(addr, USB_PREFIX_LENGTH));
		if (enabled) {
		ifcg.setInterfaceUp();
		} else {
		ifcg.setInterfaceDown();
		}
		ifcg.clearFlag("running");
		mNMService.setInterfaceConfig(iface, ifcg);
		}
		} catch (Exception e) {
		Log.e(TAG, "Error configuring interface " + iface, e);
		return false;
		}

		return true;
		}

		private void maybeLogMessage(State state, int what) {
		if (DBG) {
		Log.d(TAG, state.getName() + " got " +
		sMagicDecoderRing.get(what, Integer.toString(what)));
		}
		}

		class InitialState extends State {
		@Override
		public void enter() {
		setAvailable(true);
		setTethered(false);
		mTetherController.sendTetherStateChangedBroadcast();
		}

		@Override
		public boolean processMessage(Message message) {
		maybeLogMessage(this, message.what);
		boolean retValue = true;
		switch (message.what) {
		case CMD_TETHER_REQUESTED:
		setLastError(ConnectivityManager.TETHER_ERROR_NO_ERROR);
		mTetherController.notifyInterfaceTetheringReadiness(true, TetherInterfaceSM.this);
		transitionTo(mStartingState);
		break;
		case CMD_INTERFACE_DOWN:
		transitionTo(mUnavailableState);
		break;
		default:
		retValue = false;
		break;
		}
		return retValue;
		}
		}

		class StartingState extends State {
		@Override
		public void enter() {
		setAvailable(false);
		if (mUsb) {
		if (!configureUsbIface(true, mIfaceName)) {
		mTetherController.notifyInterfaceTetheringReadiness(false, TetherInterfaceSM.this);
		setLastError(ConnectivityManager.TETHER_ERROR_IFACE_CFG_ERROR);

		transitionTo(mInitialState);
		return;
		}
		}
		mTetherController.sendTetherStateChangedBroadcast();

		// Skipping StartingState
		transitionTo(mTetheredState);
		}
		@Override
		public boolean processMessage(Message message) {
		maybeLogMessage(this, message.what);
		boolean retValue = true;
		switch (message.what) {
		// maybe a parent class?
		case CMD_TETHER_UNREQUESTED:
		mTetherController.notifyInterfaceTetheringReadiness(false, TetherInterfaceSM.this);
		if (mUsb) {
		if (!configureUsbIface(false, mIfaceName)) {
		setLastErrorAndTransitionToInitialState(
		ConnectivityManager.TETHER_ERROR_IFACE_CFG_ERROR);
		break;
		}
		}
		transitionTo(mInitialState);
		break;
		case CMD_CELL_DUN_ERROR:
		case CMD_IP_FORWARDING_ENABLE_ERROR:
		case CMD_IP_FORWARDING_DISABLE_ERROR:
		case CMD_START_TETHERING_ERROR:
		case CMD_STOP_TETHERING_ERROR:
		case CMD_SET_DNS_FORWARDERS_ERROR:
		setLastErrorAndTransitionToInitialState(
		ConnectivityManager.TETHER_ERROR_MASTER_ERROR);
		break;
		case CMD_INTERFACE_DOWN:
		mTetherController.notifyInterfaceTetheringReadiness(false, TetherInterfaceSM.this);
		transitionTo(mUnavailableState);
		break;
		default:
		retValue = false;
		}
		return retValue;
		}
		}

		class TetheredState extends State {
		@Override
		public void enter() {
		try {
		mNMService.tetherInterface(mIfaceName);
		} catch (Exception e) {
		Log.e(TAG, "Error Tethering: " + e.toString());
		setLastError(ConnectivityManager.TETHER_ERROR_TETHER_IFACE_ERROR);

		try {
		mNMService.untetherInterface(mIfaceName);
		} catch (Exception ee) {
		Log.e(TAG, "Error untethering after failure!" + ee.toString());
		}
		transitionTo(mInitialState);
		return;
		}
		if (DBG) Log.d(TAG, "Tethered " + mIfaceName);
		setAvailable(false);
		setTethered(true);
		mTetherController.sendTetherStateChangedBroadcast();
		}

		private void cleanupUpstream() {
		if (mMyUpstreamIfaceName != null) {
		// note that we don't care about errors here.
		// sometimes interfaces are gone before we get
		// to remove their rules, which generates errors.
		// just do the best we can.
		try {
		// about to tear down NAT; gather remaining statistics
		mStatsService.forceUpdate();
		} catch (Exception e) {
		if (VDBG) Log.e(TAG, "Exception in forceUpdate: " + e.toString());
		}
		try {
		mNMService.stopInterfaceForwarding(mIfaceName, mMyUpstreamIfaceName);
		} catch (Exception e) {
		if (VDBG) Log.e(
		TAG, "Exception in removeInterfaceForward: " + e.toString());
		}
		try {
		mNMService.disableNat(mIfaceName, mMyUpstreamIfaceName);
		} catch (Exception e) {
		if (VDBG) Log.e(TAG, "Exception in disableNat: " + e.toString());
		}
		mMyUpstreamIfaceName = null;
		}
		return;
		}

		@Override
		public boolean processMessage(Message message) {
		maybeLogMessage(this, message.what);
		boolean retValue = true;
		boolean error = false;
		switch (message.what) {
		case CMD_TETHER_UNREQUESTED:
		case CMD_INTERFACE_DOWN:
		cleanupUpstream();
		try {
		mNMService.untetherInterface(mIfaceName);
		} catch (Exception e) {
		setLastErrorAndTransitionToInitialState(
		ConnectivityManager.TETHER_ERROR_UNTETHER_IFACE_ERROR);
		break;
		}
		mTetherController.notifyInterfaceTetheringReadiness(false, TetherInterfaceSM.this);
		if (message.what == CMD_TETHER_UNREQUESTED) {
		if (mUsb) {
		if (!configureUsbIface(false, mIfaceName)) {
		setLastError(
		ConnectivityManager.TETHER_ERROR_IFACE_CFG_ERROR);
		}
		}
		transitionTo(mInitialState);
		} else if (message.what == CMD_INTERFACE_DOWN) {
		transitionTo(mUnavailableState);
		}
		if (DBG) Log.d(TAG, "Untethered " + mIfaceName);
		break;
		case CMD_TETHER_CONNECTION_CHANGED:
		String newUpstreamIfaceName = (String)(message.obj);
		if ((mMyUpstreamIfaceName == null && newUpstreamIfaceName == null) \|\|
		(mMyUpstreamIfaceName != null &&
		mMyUpstreamIfaceName.equals(newUpstreamIfaceName))) {
		if (VDBG) Log.d(TAG, "Connection changed noop - dropping");
		break;
		}
		cleanupUpstream();
		if (newUpstreamIfaceName != null) {
		try {
		mNMService.enableNat(mIfaceName, newUpstreamIfaceName);
		mNMService.startInterfaceForwarding(mIfaceName,
		newUpstreamIfaceName);
		} catch (Exception e) {
		Log.e(TAG, "Exception enabling Nat: " + e.toString());
		try {
		mNMService.disableNat(mIfaceName, newUpstreamIfaceName);
		} catch (Exception ee) {}
		try {
		mNMService.untetherInterface(mIfaceName);
		} catch (Exception ee) {}

		setLastError(ConnectivityManager.TETHER_ERROR_ENABLE_NAT_ERROR);
		transitionTo(mInitialState);
		return true;
		}
		}
		mMyUpstreamIfaceName = newUpstreamIfaceName;
		break;
		case CMD_CELL_DUN_ERROR:
		case CMD_IP_FORWARDING_ENABLE_ERROR:
		case CMD_IP_FORWARDING_DISABLE_ERROR:
		case CMD_START_TETHERING_ERROR:
		case CMD_STOP_TETHERING_ERROR:
		case CMD_SET_DNS_FORWARDERS_ERROR:
		error = true;
		// fall through
		case CMD_TETHER_MODE_DEAD:
		cleanupUpstream();
		try {
		mNMService.untetherInterface(mIfaceName);
		} catch (Exception e) {
		setLastErrorAndTransitionToInitialState(
		ConnectivityManager.TETHER_ERROR_UNTETHER_IFACE_ERROR);
		break;
		}
		if (error) {
		setLastErrorAndTransitionToInitialState(
		ConnectivityManager.TETHER_ERROR_MASTER_ERROR);
		break;
		}
		if (DBG) Log.d(TAG, "Tether lost upstream connection " + mIfaceName);
		mTetherController.sendTetherStateChangedBroadcast();
		if (mUsb) {
		if (!configureUsbIface(false, mIfaceName)) {
		setLastError(ConnectivityManager.TETHER_ERROR_IFACE_CFG_ERROR);
		}
		}
		transitionTo(mInitialState);
		break;
		default:
		retValue = false;
		break;
		}
		return retValue;
		}
		}

		class UnavailableState extends State {
		@Override
		public void enter() {
		setAvailable(false);
		setLastError(ConnectivityManager.TETHER_ERROR_NO_ERROR);
		setTethered(false);
		mTetherController.sendTetherStateChangedBroadcast();
		}
		@Override
		public boolean processMessage(Message message) {
		boolean retValue = true;
		switch (message.what) {
		case CMD_INTERFACE_UP:
		transitionTo(mInitialState);
		break;
		default:
		retValue = false;
		break;
		}
		return retValue;
		}
		}

		void setLastErrorAndTransitionToInitialState(int error) {
		setLastError(error);
		transitionTo(mInitialState);
		}

		}

		/**
		* A NetworkCallback class that relays information of interest to the
		* tethering master state machine thread for subsequent processing.

services/core/java/com/android/server/connectivity/tethering/IControlsTethering.java

+1 −3

Original line number	Diff line number	Diff line
		@@ -16,8 +16,6 @@

		package com.android.server.connectivity.tethering;

		import com.android.server.connectivity.Tethering;

		/**
		* @hide
		*
		@@ -25,5 +23,5 @@ import com.android.server.connectivity.Tethering;
		*/
		public interface IControlsTethering {
		void sendTetherStateChangedBroadcast();
		void notifyInterfaceTetheringReadiness(boolean isReady, Tethering.TetherInterfaceSM who);
		void notifyInterfaceTetheringReadiness(boolean isReady, TetherInterfaceSM who);
		}
		No newline at end of file

services/core/java/com/android/server/connectivity/tethering/TetherInterfaceSM.java

0 → 100644

+483 −0

File added.

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