service/java/com/android/server/wifi/nan/WifiNanServiceImpl.java - platform/packages/modules/Wifi - Git at Google

 /*
  * Copyright (C) 2016 The Android Open Source Project
  *
  * Licensed under the Apache License, Version 2.0 (the "License");
  * you may not use this file except in compliance with the License.
  * You may obtain a copy of the License at
  *
  *      http://www.apache.org/licenses/LICENSE-2.0
  *
  * Unless required by applicable law or agreed to in writing, software
  * distributed under the License is distributed on an "AS IS" BASIS,
  * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
  * See the License for the specific language governing permissions and
  * limitations under the License.
  */

 package com.android.server.wifi.nan;

 import android.content.Context;
 import android.content.pm.PackageManager;
 import android.net.wifi.RttManager;
 import android.net.wifi.nan.ConfigRequest;
 import android.net.wifi.nan.IWifiNanDiscoverySessionCallback;
 import android.net.wifi.nan.IWifiNanEventCallback;
 import android.net.wifi.nan.IWifiNanManager;
 import android.net.wifi.nan.PublishConfig;
 import android.net.wifi.nan.SubscribeConfig;
 import android.net.wifi.nan.WifiNanDiscoveryBaseSession;
 import android.net.wifi.nan.WifiNanEventCallback;
 import android.os.Binder;
 import android.os.HandlerThread;
 import android.os.IBinder;
 import android.os.RemoteException;
 import android.util.Log;
 import android.util.SparseArray;
 import android.util.SparseIntArray;

 import java.io.FileDescriptor;
 import java.io.PrintWriter;
 import java.util.Arrays;

 /**
  * Implementation of the IWifiNanManager AIDL interface. Performs validity
  * (permission and clientID-UID mapping) checks and delegates execution to the
  * WifiNanStateManager singleton handler. Limited state to feedback which has to
  * be provided instantly: client and session IDs.
  */
 public class WifiNanServiceImpl extends IWifiNanManager.Stub {
     private static final String TAG = "WifiNanService";
     private static final boolean DBG = false;
     private static final boolean VDBG = false; // STOPSHIP if true

     private Context mContext;
     private WifiNanStateManager mStateManager;

     private final Object mLock = new Object();
     private final SparseArray<IBinder.DeathRecipient> mDeathRecipientsByClientId =
             new SparseArray<>();
     private int mNextClientId = 1;
     private int mNextRangingId = 1;
     private final SparseIntArray mUidByClientId = new SparseIntArray();

     public WifiNanServiceImpl(Context context) {
         mContext = context.getApplicationContext();
         mStateManager = WifiNanStateManager.getInstance();
     }

     /**
      * Proxy for the final native call of the parent class. Enables mocking of
      * the function.
      */
     public int getMockableCallingUid() {
         return getCallingUid();
     }

     /**
      * Start the service: allocate a new thread (for now), start the handlers of
      * the components of the service.
      */
     public void start() {
         Log.i(TAG, "Starting Wi-Fi NAN service");

         // TODO: share worker thread with other Wi-Fi handlers (b/27924886)
         HandlerThread wifiNanThread = new HandlerThread("wifiNanService");
         wifiNanThread.start();

         mStateManager.start(mContext, wifiNanThread.getLooper());
     }

     /**
      * Start/initialize portions of the service which require the boot stage to be complete.
      */
     public void startLate() {
         Log.i(TAG, "Late initialization of Wi-Fi NAN service");

         mStateManager.startLate();
     }

     @Override
     public void enableUsage() {
         enforceAccessPermission();
         enforceChangePermission();
         enforceConnectivityInternalPermission();

         mStateManager.enableUsage();
     }

     @Override
     public void disableUsage() {
         enforceAccessPermission();
         enforceChangePermission();
         enforceConnectivityInternalPermission();

         mStateManager.disableUsage();

         /*
          * Potential leak (b/27796984) since we keep app information here (uid,
          * binder-link-to-death), while clearing all state information. However:
          * (1) can't clear all information since don't have binder, (2)
          * information will clear once app dies, (3) allows us to do security
          * checks in the future.
          */
     }

     @Override
     public boolean isUsageEnabled() {
         enforceAccessPermission();

         return mStateManager.isUsageEnabled();
     }

     @Override
     public void connect(final IBinder binder, String callingPackage, IWifiNanEventCallback callback,
             ConfigRequest configRequest) {
         enforceAccessPermission();
         enforceChangePermission();
         if (callback == null) {
             throw new IllegalArgumentException("Callback must not be null");
         }
         if (binder == null) {
             throw new IllegalArgumentException("Binder must not be null");
         }

         if (configRequest != null) {
             if (configRequest.isNonDefaultOnTheAir()) {
                 enforceConnectivityInternalPermission();
             }
         } else {
             configRequest = new ConfigRequest.Builder().build();
         }
         configRequest.validate();

         final int uid = getMockableCallingUid();
         int pid = getCallingPid();

         final int clientId;
         synchronized (mLock) {
             clientId = mNextClientId++;
         }

         if (VDBG) {
             Log.v(TAG, "connect: uid=" + uid + ", clientId=" + clientId + ", configRequest"
                     + configRequest);
         }

         IBinder.DeathRecipient dr = new IBinder.DeathRecipient() {
             @Override
             public void binderDied() {
                 if (DBG) Log.d(TAG, "binderDied: clientId=" + clientId);
                 binder.unlinkToDeath(this, 0);

                 synchronized (mLock) {
                     mDeathRecipientsByClientId.delete(clientId);
                     mUidByClientId.delete(clientId);
                 }

                 mStateManager.disconnect(clientId);
             }
         };

         try {
             binder.linkToDeath(dr, 0);
         } catch (RemoteException e) {
             Log.e(TAG, "Error on linkToDeath - " + e);
             try {
                 callback.onConnectFail(WifiNanEventCallback.REASON_OTHER);
             } catch (RemoteException e1) {
                 Log.e(TAG, "Error on onConnectFail()");
             }
             return;
         }

         synchronized (mLock) {
             mDeathRecipientsByClientId.put(clientId, dr);
             mUidByClientId.put(clientId, uid);
         }

         mStateManager.connect(clientId, uid, pid, callingPackage, callback, configRequest);
     }

     @Override
     public void disconnect(int clientId, IBinder binder) {
         enforceAccessPermission();
         enforceChangePermission();

         int uid = getMockableCallingUid();
         enforceClientValidity(uid, clientId);
         if (VDBG) Log.v(TAG, "disconnect: uid=" + uid + ", clientId=" + clientId);

         if (binder == null) {
             throw new IllegalArgumentException("Binder must not be null");
         }

         synchronized (mLock) {
             IBinder.DeathRecipient dr = mDeathRecipientsByClientId.get(clientId);
             if (dr != null) {
                 binder.unlinkToDeath(dr, 0);
                 mDeathRecipientsByClientId.delete(clientId);
             }
             mUidByClientId.delete(clientId);
         }

         mStateManager.disconnect(clientId);
     }

     @Override
     public void terminateSession(int clientId, int sessionId) {
         enforceAccessPermission();
         enforceChangePermission();

         int uid = getMockableCallingUid();
         enforceClientValidity(uid, clientId);
         if (VDBG) {
             Log.v(TAG, "terminateSession: sessionId=" + sessionId + ", uid=" + uid + ", clientId="
                     + clientId);
         }

         mStateManager.terminateSession(clientId, sessionId);
     }

     @Override
     public void publish(int clientId, PublishConfig publishConfig,
             IWifiNanDiscoverySessionCallback callback) {
         enforceAccessPermission();
         enforceChangePermission();

         if (callback == null) {
             throw new IllegalArgumentException("Callback must not be null");
         }
         if (publishConfig == null) {
             throw new IllegalArgumentException("PublishConfig must not be null");
         }
         publishConfig.validate();

         int uid = getMockableCallingUid();
         enforceClientValidity(uid, clientId);
         if (VDBG) {
             Log.v(TAG, "publish: uid=" + uid + ", clientId=" + clientId + ", publishConfig="
                     + publishConfig + ", callback=" + callback);
         }

         mStateManager.publish(clientId, publishConfig, callback);
     }

     @Override
     public void updatePublish(int clientId, int sessionId, PublishConfig publishConfig) {
         enforceAccessPermission();
         enforceChangePermission();

         if (publishConfig == null) {
             throw new IllegalArgumentException("PublishConfig must not be null");
         }
         publishConfig.validate();

         int uid = getMockableCallingUid();
         enforceClientValidity(uid, clientId);
         if (VDBG) {
             Log.v(TAG, "updatePublish: uid=" + uid + ", clientId=" + clientId + ", sessionId="
                     + sessionId + ", config=" + publishConfig);
         }

         mStateManager.updatePublish(clientId, sessionId, publishConfig);
     }

     @Override
     public void subscribe(int clientId, SubscribeConfig subscribeConfig,
             IWifiNanDiscoverySessionCallback callback) {
         enforceAccessPermission();
         enforceChangePermission();

         if (callback == null) {
             throw new IllegalArgumentException("Callback must not be null");
         }
         if (subscribeConfig == null) {
             throw new IllegalArgumentException("SubscribeConfig must not be null");
         }
         subscribeConfig.validate();

         int uid = getMockableCallingUid();
         enforceClientValidity(uid, clientId);
         if (VDBG) {
             Log.v(TAG, "subscribe: uid=" + uid + ", clientId=" + clientId + ", config="
                     + subscribeConfig + ", callback=" + callback);
         }

         mStateManager.subscribe(clientId, subscribeConfig, callback);
     }

     @Override
     public void updateSubscribe(int clientId, int sessionId, SubscribeConfig subscribeConfig) {
         enforceAccessPermission();
         enforceChangePermission();

         if (subscribeConfig == null) {
             throw new IllegalArgumentException("SubscribeConfig must not be null");
         }
         subscribeConfig.validate();

         int uid = getMockableCallingUid();
         enforceClientValidity(uid, clientId);
         if (VDBG) {
             Log.v(TAG, "updateSubscribe: uid=" + uid + ", clientId=" + clientId + ", sessionId="
                     + sessionId + ", config=" + subscribeConfig);
         }

         mStateManager.updateSubscribe(clientId, sessionId, subscribeConfig);
     }

     @Override
     public void sendMessage(int clientId, int sessionId, int peerId, byte[] message, int messageId,
             int retryCount) {
         enforceAccessPermission();
         enforceChangePermission();

         if (retryCount < 0 || retryCount > WifiNanDiscoveryBaseSession.getMaxSendRetryCount()) {
             throw new IllegalArgumentException("Invalid 'retryCount' must be non-negative "
                     + "and <= WifiNanDiscoveryBaseSession.MAX_SEND_RETRY_COUNT");
         }

         int uid = getMockableCallingUid();
         enforceClientValidity(uid, clientId);
         if (VDBG) {
             Log.v(TAG,
                     "sendMessage: sessionId=" + sessionId + ", uid=" + uid + ", clientId="
                             + clientId + ", peerId=" + peerId + ", messageId=" + messageId
                             + ", retryCount=" + retryCount);
         }

         mStateManager.sendMessage(clientId, sessionId, peerId, message, messageId, retryCount);
     }

     @Override
     public int startRanging(int clientId, int sessionId, RttManager.ParcelableRttParams params) {
         enforceAccessPermission();
         enforceLocationPermission();

         int uid = getMockableCallingUid();
         enforceClientValidity(uid, clientId);
         if (VDBG) {
             Log.v(TAG, "startRanging: clientId=" + clientId + ", sessionId=" + sessionId + ", "
                     + ", parms=" + Arrays.toString(params.mParams));
         }

         if (params.mParams.length == 0) {
             throw new IllegalArgumentException("Empty ranging parameters");
         }

         int rangingId;
         synchronized (mLock) {
             rangingId = mNextRangingId++;
         }
         mStateManager.startRanging(clientId, sessionId, params.mParams, rangingId);
         return rangingId;
     }

     @Override
     protected void dump(FileDescriptor fd, PrintWriter pw, String[] args) {
         if (mContext.checkCallingOrSelfPermission(
                 android.Manifest.permission.DUMP) != PackageManager.PERMISSION_GRANTED) {
             pw.println("Permission Denial: can't dump WifiNanService from pid="
                     + Binder.getCallingPid() + ", uid=" + Binder.getCallingUid());
             return;
         }
         pw.println("Wi-Fi NAN Service");
         synchronized (mLock) {
             pw.println("  mNextClientId: " + mNextClientId);
             pw.println("  mDeathRecipientsByClientId: " + mDeathRecipientsByClientId);
             pw.println("  mUidByClientId: " + mUidByClientId);
         }
         mStateManager.dump(fd, pw, args);
     }

     private void enforceClientValidity(int uid, int clientId) {
         synchronized (mLock) {
             int uidIndex = mUidByClientId.indexOfKey(clientId);
             if (uidIndex < 0 || mUidByClientId.valueAt(uidIndex) != uid) {
                 throw new SecurityException("Attempting to use invalid uid+clientId mapping: uid="
                         + uid + ", clientId=" + clientId);
             }
         }
     }

     private void enforceAccessPermission() {
         mContext.enforceCallingOrSelfPermission(android.Manifest.permission.ACCESS_WIFI_STATE, TAG);
     }

     private void enforceChangePermission() {
         mContext.enforceCallingOrSelfPermission(android.Manifest.permission.CHANGE_WIFI_STATE, TAG);
     }

     private void enforceLocationPermission() {
         mContext.enforceCallingOrSelfPermission(android.Manifest.permission.ACCESS_COARSE_LOCATION,
                 TAG);
     }

     private void enforceConnectivityInternalPermission() {
         mContext.enforceCallingOrSelfPermission(android.Manifest.permission.CONNECTIVITY_INTERNAL,
                 TAG);
     }
 }
	/*
	* Copyright (C) 2016 The Android Open Source Project
	*
	* Licensed under the Apache License, Version 2.0 (the "License");
	* you may not use this file except in compliance with the License.
	* You may obtain a copy of the License at
	*
	* http://www.apache.org/licenses/LICENSE-2.0
	*
	* Unless required by applicable law or agreed to in writing, software
	* distributed under the License is distributed on an "AS IS" BASIS,
	* WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
	* See the License for the specific language governing permissions and
	* limitations under the License.
	*/

	package com.android.server.wifi.nan;

	import android.content.Context;
	import android.content.pm.PackageManager;
	import android.net.wifi.RttManager;
	import android.net.wifi.nan.ConfigRequest;
	import android.net.wifi.nan.IWifiNanDiscoverySessionCallback;
	import android.net.wifi.nan.IWifiNanEventCallback;
	import android.net.wifi.nan.IWifiNanManager;
	import android.net.wifi.nan.PublishConfig;
	import android.net.wifi.nan.SubscribeConfig;
	import android.net.wifi.nan.WifiNanDiscoveryBaseSession;
	import android.net.wifi.nan.WifiNanEventCallback;
	import android.os.Binder;
	import android.os.HandlerThread;
	import android.os.IBinder;
	import android.os.RemoteException;
	import android.util.Log;
	import android.util.SparseArray;
	import android.util.SparseIntArray;

	import java.io.FileDescriptor;
	import java.io.PrintWriter;
	import java.util.Arrays;

	/**
	* Implementation of the IWifiNanManager AIDL interface. Performs validity
	* (permission and clientID-UID mapping) checks and delegates execution to the
	* WifiNanStateManager singleton handler. Limited state to feedback which has to
	* be provided instantly: client and session IDs.
	*/
	public class WifiNanServiceImpl extends IWifiNanManager.Stub {
	private static final String TAG = "WifiNanService";
	private static final boolean DBG = false;
	private static final boolean VDBG = false; // STOPSHIP if true

	private Context mContext;
	private WifiNanStateManager mStateManager;

	private final Object mLock = new Object();
	private final SparseArray<IBinder.DeathRecipient> mDeathRecipientsByClientId =
	new SparseArray<>();
	private int mNextClientId = 1;
	private int mNextRangingId = 1;
	private final SparseIntArray mUidByClientId = new SparseIntArray();

	public WifiNanServiceImpl(Context context) {
	mContext = context.getApplicationContext();
	mStateManager = WifiNanStateManager.getInstance();
	}

	/**
	* Proxy for the final native call of the parent class. Enables mocking of
	* the function.
	*/
	public int getMockableCallingUid() {
	return getCallingUid();
	}

	/**
	* Start the service: allocate a new thread (for now), start the handlers of
	* the components of the service.
	*/
	public void start() {
	Log.i(TAG, "Starting Wi-Fi NAN service");

	// TODO: share worker thread with other Wi-Fi handlers (b/27924886)
	HandlerThread wifiNanThread = new HandlerThread("wifiNanService");
	wifiNanThread.start();

	mStateManager.start(mContext, wifiNanThread.getLooper());
	}

	/**
	* Start/initialize portions of the service which require the boot stage to be complete.
	*/
	public void startLate() {
	Log.i(TAG, "Late initialization of Wi-Fi NAN service");

	mStateManager.startLate();
	}

	@Override
	public void enableUsage() {
	enforceAccessPermission();
	enforceChangePermission();
	enforceConnectivityInternalPermission();

	mStateManager.enableUsage();
	}

	@Override
	public void disableUsage() {
	enforceAccessPermission();
	enforceChangePermission();
	enforceConnectivityInternalPermission();

	mStateManager.disableUsage();

	/*
	* Potential leak (b/27796984) since we keep app information here (uid,
	* binder-link-to-death), while clearing all state information. However:
	* (1) can't clear all information since don't have binder, (2)
	* information will clear once app dies, (3) allows us to do security
	* checks in the future.
	*/
	}

	@Override
	public boolean isUsageEnabled() {
	enforceAccessPermission();

	return mStateManager.isUsageEnabled();
	}

	@Override
	public void connect(final IBinder binder, String callingPackage, IWifiNanEventCallback callback,
	ConfigRequest configRequest) {
	enforceAccessPermission();
	enforceChangePermission();
	if (callback == null) {
	throw new IllegalArgumentException("Callback must not be null");
	}
	if (binder == null) {
	throw new IllegalArgumentException("Binder must not be null");
	}

	if (configRequest != null) {
	if (configRequest.isNonDefaultOnTheAir()) {
	enforceConnectivityInternalPermission();
	}
	} else {
	configRequest = new ConfigRequest.Builder().build();
	}
	configRequest.validate();

	final int uid = getMockableCallingUid();
	int pid = getCallingPid();

	final int clientId;
	synchronized (mLock) {
	clientId = mNextClientId++;
	}

	if (VDBG) {
	Log.v(TAG, "connect: uid=" + uid + ", clientId=" + clientId + ", configRequest"
	+ configRequest);
	}

	IBinder.DeathRecipient dr = new IBinder.DeathRecipient() {
	@Override
	public void binderDied() {
	if (DBG) Log.d(TAG, "binderDied: clientId=" + clientId);
	binder.unlinkToDeath(this, 0);

	synchronized (mLock) {
	mDeathRecipientsByClientId.delete(clientId);
	mUidByClientId.delete(clientId);
	}

	mStateManager.disconnect(clientId);
	}
	};

	try {
	binder.linkToDeath(dr, 0);
	} catch (RemoteException e) {
	Log.e(TAG, "Error on linkToDeath - " + e);
	try {
	callback.onConnectFail(WifiNanEventCallback.REASON_OTHER);
	} catch (RemoteException e1) {
	Log.e(TAG, "Error on onConnectFail()");
	}
	return;
	}

	synchronized (mLock) {
	mDeathRecipientsByClientId.put(clientId, dr);
	mUidByClientId.put(clientId, uid);
	}

	mStateManager.connect(clientId, uid, pid, callingPackage, callback, configRequest);
	}

	@Override
	public void disconnect(int clientId, IBinder binder) {
	enforceAccessPermission();
	enforceChangePermission();

	int uid = getMockableCallingUid();
	enforceClientValidity(uid, clientId);
	if (VDBG) Log.v(TAG, "disconnect: uid=" + uid + ", clientId=" + clientId);

	if (binder == null) {
	throw new IllegalArgumentException("Binder must not be null");
	}

	synchronized (mLock) {
	IBinder.DeathRecipient dr = mDeathRecipientsByClientId.get(clientId);
	if (dr != null) {
	binder.unlinkToDeath(dr, 0);
	mDeathRecipientsByClientId.delete(clientId);
	}
	mUidByClientId.delete(clientId);
	}

	mStateManager.disconnect(clientId);
	}

	@Override
	public void terminateSession(int clientId, int sessionId) {
	enforceAccessPermission();
	enforceChangePermission();

	int uid = getMockableCallingUid();
	enforceClientValidity(uid, clientId);
	if (VDBG) {
	Log.v(TAG, "terminateSession: sessionId=" + sessionId + ", uid=" + uid + ", clientId="
	+ clientId);
	}

	mStateManager.terminateSession(clientId, sessionId);
	}

	@Override
	public void publish(int clientId, PublishConfig publishConfig,
	IWifiNanDiscoverySessionCallback callback) {
	enforceAccessPermission();
	enforceChangePermission();

	if (callback == null) {
	throw new IllegalArgumentException("Callback must not be null");
	}
	if (publishConfig == null) {
	throw new IllegalArgumentException("PublishConfig must not be null");
	}
	publishConfig.validate();

	int uid = getMockableCallingUid();
	enforceClientValidity(uid, clientId);
	if (VDBG) {
	Log.v(TAG, "publish: uid=" + uid + ", clientId=" + clientId + ", publishConfig="
	+ publishConfig + ", callback=" + callback);
	}

	mStateManager.publish(clientId, publishConfig, callback);
	}

	@Override
	public void updatePublish(int clientId, int sessionId, PublishConfig publishConfig) {
	enforceAccessPermission();
	enforceChangePermission();

	if (publishConfig == null) {
	throw new IllegalArgumentException("PublishConfig must not be null");
	}
	publishConfig.validate();

	int uid = getMockableCallingUid();
	enforceClientValidity(uid, clientId);
	if (VDBG) {
	Log.v(TAG, "updatePublish: uid=" + uid + ", clientId=" + clientId + ", sessionId="
	+ sessionId + ", config=" + publishConfig);
	}

	mStateManager.updatePublish(clientId, sessionId, publishConfig);
	}

	@Override
	public void subscribe(int clientId, SubscribeConfig subscribeConfig,
	IWifiNanDiscoverySessionCallback callback) {
	enforceAccessPermission();
	enforceChangePermission();

	if (callback == null) {
	throw new IllegalArgumentException("Callback must not be null");
	}
	if (subscribeConfig == null) {
	throw new IllegalArgumentException("SubscribeConfig must not be null");
	}
	subscribeConfig.validate();

	int uid = getMockableCallingUid();
	enforceClientValidity(uid, clientId);
	if (VDBG) {
	Log.v(TAG, "subscribe: uid=" + uid + ", clientId=" + clientId + ", config="
	+ subscribeConfig + ", callback=" + callback);
	}

	mStateManager.subscribe(clientId, subscribeConfig, callback);
	}

	@Override
	public void updateSubscribe(int clientId, int sessionId, SubscribeConfig subscribeConfig) {
	enforceAccessPermission();
	enforceChangePermission();

	if (subscribeConfig == null) {
	throw new IllegalArgumentException("SubscribeConfig must not be null");
	}
	subscribeConfig.validate();

	int uid = getMockableCallingUid();
	enforceClientValidity(uid, clientId);
	if (VDBG) {
	Log.v(TAG, "updateSubscribe: uid=" + uid + ", clientId=" + clientId + ", sessionId="
	+ sessionId + ", config=" + subscribeConfig);
	}

	mStateManager.updateSubscribe(clientId, sessionId, subscribeConfig);
	}

	@Override
	public void sendMessage(int clientId, int sessionId, int peerId, byte[] message, int messageId,
	int retryCount) {
	enforceAccessPermission();
	enforceChangePermission();

	if (retryCount < 0 \|\| retryCount > WifiNanDiscoveryBaseSession.getMaxSendRetryCount()) {
	throw new IllegalArgumentException("Invalid 'retryCount' must be non-negative "
	+ "and <= WifiNanDiscoveryBaseSession.MAX_SEND_RETRY_COUNT");
	}

	int uid = getMockableCallingUid();
	enforceClientValidity(uid, clientId);
	if (VDBG) {
	Log.v(TAG,
	"sendMessage: sessionId=" + sessionId + ", uid=" + uid + ", clientId="
	+ clientId + ", peerId=" + peerId + ", messageId=" + messageId
	+ ", retryCount=" + retryCount);
	}

	mStateManager.sendMessage(clientId, sessionId, peerId, message, messageId, retryCount);
	}

	@Override
	public int startRanging(int clientId, int sessionId, RttManager.ParcelableRttParams params) {
	enforceAccessPermission();
	enforceLocationPermission();

	int uid = getMockableCallingUid();
	enforceClientValidity(uid, clientId);
	if (VDBG) {
	Log.v(TAG, "startRanging: clientId=" + clientId + ", sessionId=" + sessionId + ", "
	+ ", parms=" + Arrays.toString(params.mParams));
	}

	if (params.mParams.length == 0) {
	throw new IllegalArgumentException("Empty ranging parameters");
	}

	int rangingId;
	synchronized (mLock) {
	rangingId = mNextRangingId++;
	}
	mStateManager.startRanging(clientId, sessionId, params.mParams, rangingId);
	return rangingId;
	}

	@Override
	protected void dump(FileDescriptor fd, PrintWriter pw, String[] args) {
	if (mContext.checkCallingOrSelfPermission(
	android.Manifest.permission.DUMP) != PackageManager.PERMISSION_GRANTED) {
	pw.println("Permission Denial: can't dump WifiNanService from pid="
	+ Binder.getCallingPid() + ", uid=" + Binder.getCallingUid());
	return;
	}
	pw.println("Wi-Fi NAN Service");
	synchronized (mLock) {
	pw.println(" mNextClientId: " + mNextClientId);
	pw.println(" mDeathRecipientsByClientId: " + mDeathRecipientsByClientId);
	pw.println(" mUidByClientId: " + mUidByClientId);
	}
	mStateManager.dump(fd, pw, args);
	}

	private void enforceClientValidity(int uid, int clientId) {
	synchronized (mLock) {
	int uidIndex = mUidByClientId.indexOfKey(clientId);
	if (uidIndex < 0 \|\| mUidByClientId.valueAt(uidIndex) != uid) {
	throw new SecurityException("Attempting to use invalid uid+clientId mapping: uid="
	+ uid + ", clientId=" + clientId);
	}
	}
	}

	private void enforceAccessPermission() {
	mContext.enforceCallingOrSelfPermission(android.Manifest.permission.ACCESS_WIFI_STATE, TAG);
	}

	private void enforceChangePermission() {
	mContext.enforceCallingOrSelfPermission(android.Manifest.permission.CHANGE_WIFI_STATE, TAG);
	}

	private void enforceLocationPermission() {
	mContext.enforceCallingOrSelfPermission(android.Manifest.permission.ACCESS_COARSE_LOCATION,
	TAG);
	}

	private void enforceConnectivityInternalPermission() {
	mContext.enforceCallingOrSelfPermission(android.Manifest.permission.CONNECTIVITY_INTERNAL,
	TAG);
	}
	}