/* * Copyright (C) 2011 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 android.net.wifi; import android.app.Notification; import android.app.NotificationManager; import android.app.PendingIntent; import android.content.BroadcastReceiver; import android.content.ContentResolver; import android.content.Context; import android.content.Intent; import android.content.IntentFilter; import android.content.res.Resources; import android.database.ContentObserver; import android.net.ConnectivityManager; import android.net.DnsPinger; import android.net.NetworkInfo; import android.net.Uri; import android.os.Message; import android.os.SystemClock; import android.os.SystemProperties; import android.provider.Settings; import android.provider.Settings.Secure; import android.util.Log; import com.android.internal.R; import com.android.internal.util.Protocol; import com.android.internal.util.State; import com.android.internal.util.StateMachine; import java.io.IOException; import java.io.PrintWriter; import java.net.HttpURLConnection; import java.net.InetAddress; import java.net.URL; import java.util.HashMap; import java.util.HashSet; import java.util.List; /** * {@link WifiWatchdogStateMachine} monitors the initial connection to a Wi-Fi * network with multiple access points. After the framework successfully * connects to an access point, the watchdog verifies connectivity by 'pinging' * the configured DNS server using {@link DnsPinger}. *

* On DNS check failure, the BSSID is blacklisted if it is reasonably likely * that another AP might have internet access; otherwise the SSID is disabled. *

* On DNS success, the WatchdogService initiates a walled garden check via an * http get. A browser window is activated if a walled garden is detected. * * @hide */ public class WifiWatchdogStateMachine extends StateMachine { private static final boolean DBG = false; private static final String TAG = "WifiWatchdogStateMachine"; private static final String DISABLED_NETWORK_NOTIFICATION_ID = "WifiWatchdog.networkdisabled"; private static final String WALLED_GARDEN_NOTIFICATION_ID = "WifiWatchdog.walledgarden"; private static final int WIFI_SIGNAL_LEVELS = 4; /** * Low signal is defined as less than or equal to cut off */ private static final int LOW_SIGNAL_CUTOFF = 0; private static final long DEFAULT_DNS_CHECK_SHORT_INTERVAL_MS = 2 * 60 * 1000; private static final long DEFAULT_DNS_CHECK_LONG_INTERVAL_MS = 60 * 60 * 1000; private static final long DEFAULT_WALLED_GARDEN_INTERVAL_MS = 30 * 60 * 1000; private static final int DEFAULT_MAX_SSID_BLACKLISTS = 7; private static final int DEFAULT_NUM_DNS_PINGS = 5; // Multiple pings to detect setup issues private static final int DEFAULT_MIN_DNS_RESPONSES = 1; private static final int DEFAULT_DNS_PING_TIMEOUT_MS = 2000; private static final long DEFAULT_BLACKLIST_FOLLOWUP_INTERVAL_MS = 15 * 1000; // See http://go/clientsdns for usage approval private static final String DEFAULT_WALLED_GARDEN_URL = "http://clients3.google.com/generate_204"; private static final int WALLED_GARDEN_SOCKET_TIMEOUT_MS = 10000; /* Some carrier apps might have support captive portal handling. Add some delay to allow app authentication to be done before our test. TODO: This should go away once we provide an API to apps to disable walled garden test for certain SSIDs */ private static final int WALLED_GARDEN_START_DELAY_MS = 3000; private static final int DNS_INTRATEST_PING_INTERVAL_MS = 200; /* With some router setups, it takes a few hunder milli-seconds before connection is active */ private static final int DNS_START_DELAY_MS = 1000; private static final int BASE = Protocol.BASE_WIFI_WATCHDOG; /** * Indicates the enable setting of WWS may have changed */ private static final int EVENT_WATCHDOG_TOGGLED = BASE + 1; /** * Indicates the wifi network state has changed. Passed w/ original intent * which has a non-null networkInfo object */ private static final int EVENT_NETWORK_STATE_CHANGE = BASE + 2; /** * Indicates the signal has changed. Passed with arg1 * {@link #mNetEventCounter} and arg2 [raw signal strength] */ private static final int EVENT_RSSI_CHANGE = BASE + 3; private static final int EVENT_SCAN_RESULTS_AVAILABLE = BASE + 4; private static final int EVENT_WIFI_RADIO_STATE_CHANGE = BASE + 5; private static final int EVENT_WATCHDOG_SETTINGS_CHANGE = BASE + 6; private static final int MESSAGE_HANDLE_WALLED_GARDEN = BASE + 100; private static final int MESSAGE_HANDLE_BAD_AP = BASE + 101; /** * arg1 == mOnlineWatchState.checkCount */ private static final int MESSAGE_SINGLE_DNS_CHECK = BASE + 102; private static final int MESSAGE_NETWORK_FOLLOWUP = BASE + 103; private static final int MESSAGE_DELAYED_WALLED_GARDEN_CHECK = BASE + 104; private Context mContext; private ContentResolver mContentResolver; private WifiManager mWifiManager; private DnsPinger mDnsPinger; private IntentFilter mIntentFilter; private BroadcastReceiver mBroadcastReceiver; private DefaultState mDefaultState = new DefaultState(); private WatchdogDisabledState mWatchdogDisabledState = new WatchdogDisabledState(); private WatchdogEnabledState mWatchdogEnabledState = new WatchdogEnabledState(); private NotConnectedState mNotConnectedState = new NotConnectedState(); private ConnectedState mConnectedState = new ConnectedState(); private DnsCheckingState mDnsCheckingState = new DnsCheckingState(); private OnlineWatchState mOnlineWatchState = new OnlineWatchState(); private OnlineState mOnlineState = new OnlineState(); private DnsCheckFailureState mDnsCheckFailureState = new DnsCheckFailureState(); private DelayWalledGardenState mDelayWalledGardenState = new DelayWalledGardenState(); private WalledGardenState mWalledGardenState = new WalledGardenState(); private BlacklistedApState mBlacklistedApState = new BlacklistedApState(); private long mDnsCheckShortIntervalMs; private long mDnsCheckLongIntervalMs; private long mWalledGardenIntervalMs; private int mMaxSsidBlacklists; private int mNumDnsPings; private int mMinDnsResponses; private int mDnsPingTimeoutMs; private long mBlacklistFollowupIntervalMs; private boolean mPoorNetworkDetectionEnabled; private boolean mWalledGardenTestEnabled; private String mWalledGardenUrl; private boolean mShowDisabledNotification; /** * The {@link WifiInfo} object passed to WWSM on network broadcasts */ private WifiInfo mConnectionInfo; private int mNetEventCounter = 0; /** * Currently maintained but not used, TODO */ private HashSet mBssids = new HashSet(); private int mNumCheckFailures = 0; private Long mLastWalledGardenCheckTime = null; /** * This is set by the blacklisted state and reset when connected to a new AP. * It triggers a disableNetwork call if a DNS check fails. */ public boolean mDisableAPNextFailure = false; private static boolean sWifiOnly = false; private boolean mDisabledNotificationShown; private boolean mWalledGardenNotificationShown; public boolean mHasConnectedWifiManager = false; /** * STATE MAP * Default * / \ * Disabled Enabled * / \ * NotConnected Connected * /---------\ * (all other states) */ private WifiWatchdogStateMachine(Context context) { super(TAG); mContext = context; mContentResolver = context.getContentResolver(); mWifiManager = (WifiManager) context.getSystemService(Context.WIFI_SERVICE); mDnsPinger = new DnsPinger(mContext, "WifiWatchdogStateMachine.DnsPinger", this.getHandler().getLooper(), this.getHandler(), ConnectivityManager.TYPE_WIFI); setupNetworkReceiver(); // The content observer to listen needs a handler registerForSettingsChanges(); registerForWatchdogToggle(); addState(mDefaultState); addState(mWatchdogDisabledState, mDefaultState); addState(mWatchdogEnabledState, mDefaultState); addState(mNotConnectedState, mWatchdogEnabledState); addState(mConnectedState, mWatchdogEnabledState); addState(mDnsCheckingState, mConnectedState); addState(mDnsCheckFailureState, mConnectedState); addState(mDelayWalledGardenState, mConnectedState); addState(mWalledGardenState, mConnectedState); addState(mBlacklistedApState, mConnectedState); addState(mOnlineWatchState, mConnectedState); addState(mOnlineState, mConnectedState); setInitialState(mWatchdogDisabledState); updateSettings(); } public static WifiWatchdogStateMachine makeWifiWatchdogStateMachine(Context context) { ContentResolver contentResolver = context.getContentResolver(); ConnectivityManager cm = (ConnectivityManager) context.getSystemService( Context.CONNECTIVITY_SERVICE); sWifiOnly = (cm.isNetworkSupported(ConnectivityManager.TYPE_MOBILE) == false); // Disable for wifi only devices. if (Settings.Secure.getString(contentResolver, Settings.Secure.WIFI_WATCHDOG_ON) == null && sWifiOnly) { putSettingsBoolean(contentResolver, Settings.Secure.WIFI_WATCHDOG_ON, false); } WifiWatchdogStateMachine wwsm = new WifiWatchdogStateMachine(context); wwsm.start(); wwsm.sendMessage(EVENT_WATCHDOG_TOGGLED); return wwsm; } /** * */ private void setupNetworkReceiver() { mBroadcastReceiver = new BroadcastReceiver() { @Override public void onReceive(Context context, Intent intent) { String action = intent.getAction(); if (action.equals(WifiManager.NETWORK_STATE_CHANGED_ACTION)) { sendMessage(EVENT_NETWORK_STATE_CHANGE, intent); } else if (action.equals(WifiManager.RSSI_CHANGED_ACTION)) { obtainMessage(EVENT_RSSI_CHANGE, mNetEventCounter, intent.getIntExtra(WifiManager.EXTRA_NEW_RSSI, -200)).sendToTarget(); } else if (action.equals(WifiManager.SCAN_RESULTS_AVAILABLE_ACTION)) { sendMessage(EVENT_SCAN_RESULTS_AVAILABLE); } else if (action.equals(WifiManager.WIFI_STATE_CHANGED_ACTION)) { sendMessage(EVENT_WIFI_RADIO_STATE_CHANGE, intent.getIntExtra(WifiManager.EXTRA_WIFI_STATE, WifiManager.WIFI_STATE_UNKNOWN)); } } }; mIntentFilter = new IntentFilter(); mIntentFilter.addAction(WifiManager.NETWORK_STATE_CHANGED_ACTION); mIntentFilter.addAction(WifiManager.WIFI_STATE_CHANGED_ACTION); mIntentFilter.addAction(WifiManager.RSSI_CHANGED_ACTION); mIntentFilter.addAction(WifiManager.SCAN_RESULTS_AVAILABLE_ACTION); } /** * Observes the watchdog on/off setting, and takes action when changed. */ private void registerForWatchdogToggle() { ContentObserver contentObserver = new ContentObserver(this.getHandler()) { @Override public void onChange(boolean selfChange) { sendMessage(EVENT_WATCHDOG_TOGGLED); } }; mContext.getContentResolver().registerContentObserver( Settings.Secure.getUriFor(Settings.Secure.WIFI_WATCHDOG_ON), false, contentObserver); } /** * Observes watchdogs secure setting changes. */ private void registerForSettingsChanges() { ContentObserver contentObserver = new ContentObserver(this.getHandler()) { @Override public void onChange(boolean selfChange) { sendMessage(EVENT_WATCHDOG_SETTINGS_CHANGE); } }; mContext.getContentResolver().registerContentObserver( Settings.Secure.getUriFor( Settings.Secure.WIFI_WATCHDOG_DNS_CHECK_SHORT_INTERVAL_MS), false, contentObserver); mContext.getContentResolver().registerContentObserver( Settings.Secure.getUriFor(Settings.Secure.WIFI_WATCHDOG_DNS_CHECK_LONG_INTERVAL_MS), false, contentObserver); mContext.getContentResolver().registerContentObserver( Settings.Secure.getUriFor(Settings.Secure.WIFI_WATCHDOG_WALLED_GARDEN_INTERVAL_MS), false, contentObserver); mContext.getContentResolver().registerContentObserver( Settings.Secure.getUriFor(Settings.Secure.WIFI_WATCHDOG_MAX_SSID_BLACKLISTS), false, contentObserver); mContext.getContentResolver().registerContentObserver( Settings.Secure.getUriFor(Settings.Secure.WIFI_WATCHDOG_NUM_DNS_PINGS), false, contentObserver); mContext.getContentResolver().registerContentObserver( Settings.Secure.getUriFor(Settings.Secure.WIFI_WATCHDOG_MIN_DNS_RESPONSES), false, contentObserver); mContext.getContentResolver().registerContentObserver( Settings.Secure.getUriFor(Settings.Secure.WIFI_WATCHDOG_DNS_PING_TIMEOUT_MS), false, contentObserver); mContext.getContentResolver().registerContentObserver( Settings.Secure.getUriFor( Settings.Secure.WIFI_WATCHDOG_BLACKLIST_FOLLOWUP_INTERVAL_MS), false, contentObserver); mContext.getContentResolver().registerContentObserver( Settings.Secure.getUriFor(Settings.Secure.WIFI_WATCHDOG_WALLED_GARDEN_TEST_ENABLED), false, contentObserver); mContext.getContentResolver().registerContentObserver( Settings.Secure.getUriFor(Settings.Secure.WIFI_WATCHDOG_WALLED_GARDEN_URL), false, contentObserver); mContext.getContentResolver().registerContentObserver( Settings.Secure.getUriFor(Settings.Secure.WIFI_WATCHDOG_SHOW_DISABLED_NETWORK_POPUP) , false, contentObserver); } /** * DNS based detection techniques do not work at all hotspots. The one sure * way to check a walled garden is to see if a URL fetch on a known address * fetches the data we expect */ private boolean isWalledGardenConnection() { HttpURLConnection urlConnection = null; try { URL url = new URL(mWalledGardenUrl); urlConnection = (HttpURLConnection) url.openConnection(); urlConnection.setInstanceFollowRedirects(false); urlConnection.setConnectTimeout(WALLED_GARDEN_SOCKET_TIMEOUT_MS); urlConnection.setReadTimeout(WALLED_GARDEN_SOCKET_TIMEOUT_MS); urlConnection.setUseCaches(false); urlConnection.getInputStream(); // We got a valid response, but not from the real google return urlConnection.getResponseCode() != 204; } catch (IOException e) { if (DBG) { log("Walled garden check - probably not a portal: exception " + e); } return false; } finally { if (urlConnection != null) { urlConnection.disconnect(); } } } private boolean rssiStrengthAboveCutoff(int rssi) { return WifiManager.calculateSignalLevel(rssi, WIFI_SIGNAL_LEVELS) > LOW_SIGNAL_CUTOFF; } public void dump(PrintWriter pw) { pw.print("WatchdogStatus: "); pw.print("State " + getCurrentState()); pw.println(", network [" + mConnectionInfo + "]"); pw.print("checkFailures " + mNumCheckFailures); pw.println(", bssids: " + mBssids); pw.println("lastSingleCheck: " + mOnlineWatchState.lastCheckTime); } private boolean isWatchdogEnabled() { return getSettingsBoolean(mContentResolver, Settings.Secure.WIFI_WATCHDOG_ON, true); } private void updateSettings() { mDnsCheckShortIntervalMs = Secure.getLong(mContentResolver, Secure.WIFI_WATCHDOG_DNS_CHECK_SHORT_INTERVAL_MS, DEFAULT_DNS_CHECK_SHORT_INTERVAL_MS); mDnsCheckLongIntervalMs = Secure.getLong(mContentResolver, Secure.WIFI_WATCHDOG_DNS_CHECK_LONG_INTERVAL_MS, DEFAULT_DNS_CHECK_LONG_INTERVAL_MS); mMaxSsidBlacklists = Secure.getInt(mContentResolver, Secure.WIFI_WATCHDOG_MAX_SSID_BLACKLISTS, DEFAULT_MAX_SSID_BLACKLISTS); mNumDnsPings = Secure.getInt(mContentResolver, Secure.WIFI_WATCHDOG_NUM_DNS_PINGS, DEFAULT_NUM_DNS_PINGS); mMinDnsResponses = Secure.getInt(mContentResolver, Secure.WIFI_WATCHDOG_MIN_DNS_RESPONSES, DEFAULT_MIN_DNS_RESPONSES); mDnsPingTimeoutMs = Secure.getInt(mContentResolver, Secure.WIFI_WATCHDOG_DNS_PING_TIMEOUT_MS, DEFAULT_DNS_PING_TIMEOUT_MS); mBlacklistFollowupIntervalMs = Secure.getLong(mContentResolver, Settings.Secure.WIFI_WATCHDOG_BLACKLIST_FOLLOWUP_INTERVAL_MS, DEFAULT_BLACKLIST_FOLLOWUP_INTERVAL_MS); //TODO: enable this by default after changing watchdog behavior //Also, update settings description mPoorNetworkDetectionEnabled = getSettingsBoolean(mContentResolver, Settings.Secure.WIFI_WATCHDOG_POOR_NETWORK_TEST_ENABLED, false); mWalledGardenTestEnabled = getSettingsBoolean(mContentResolver, Settings.Secure.WIFI_WATCHDOG_WALLED_GARDEN_TEST_ENABLED, true); mWalledGardenUrl = getSettingsStr(mContentResolver, Settings.Secure.WIFI_WATCHDOG_WALLED_GARDEN_URL, DEFAULT_WALLED_GARDEN_URL); mWalledGardenIntervalMs = Secure.getLong(mContentResolver, Secure.WIFI_WATCHDOG_WALLED_GARDEN_INTERVAL_MS, DEFAULT_WALLED_GARDEN_INTERVAL_MS); mShowDisabledNotification = getSettingsBoolean(mContentResolver, Settings.Secure.WIFI_WATCHDOG_SHOW_DISABLED_NETWORK_POPUP, true); } /** * Helper to return wait time left given a min interval and last run * * @param interval minimum wait interval * @param lastTime last time action was performed in * SystemClock.elapsedRealtime(). Null if never. * @return non negative time to wait */ private static long waitTime(long interval, Long lastTime) { if (lastTime == null) return 0; long wait = interval + lastTime - SystemClock.elapsedRealtime(); return wait > 0 ? wait : 0; } private static String wifiInfoToStr(WifiInfo wifiInfo) { if (wifiInfo == null) return "null"; return "(" + wifiInfo.getSSID() + ", " + wifiInfo.getBSSID() + ")"; } /** * Uses {@link #mConnectionInfo}. */ private void updateBssids() { String curSsid = mConnectionInfo.getSSID(); List results = mWifiManager.getScanResults(); int oldNumBssids = mBssids.size(); if (results == null) { if (DBG) { log("updateBssids: Got null scan results!"); } return; } for (ScanResult result : results) { if (result == null || result.SSID == null) { if (DBG) { log("Received invalid scan result: " + result); } continue; } if (curSsid.equals(result.SSID)) mBssids.add(result.BSSID); } } private void resetWatchdogState() { if (DBG) { log("Resetting watchdog state..."); } mConnectionInfo = null; mDisableAPNextFailure = false; mLastWalledGardenCheckTime = null; mNumCheckFailures = 0; mBssids.clear(); setDisabledNetworkNotificationVisible(false); setWalledGardenNotificationVisible(false); } private void setWalledGardenNotificationVisible(boolean visible) { // If it should be hidden and it is already hidden, then noop if (!visible && !mWalledGardenNotificationShown) { return; } Resources r = Resources.getSystem(); NotificationManager notificationManager = (NotificationManager) mContext .getSystemService(Context.NOTIFICATION_SERVICE); if (visible) { Intent intent = new Intent(Intent.ACTION_VIEW, Uri.parse(mWalledGardenUrl)); intent.setFlags(Intent.FLAG_ACTIVITY_BROUGHT_TO_FRONT | Intent.FLAG_ACTIVITY_NEW_TASK); CharSequence title = r.getString(R.string.wifi_available_sign_in, 0); CharSequence details = r.getString(R.string.wifi_available_sign_in_detailed, mConnectionInfo.getSSID()); Notification notification = new Notification(); notification.when = 0; notification.icon = com.android.internal.R.drawable.stat_notify_wifi_in_range; notification.flags = Notification.FLAG_AUTO_CANCEL; notification.contentIntent = PendingIntent.getActivity(mContext, 0, intent, 0); notification.tickerText = title; notification.setLatestEventInfo(mContext, title, details, notification.contentIntent); notificationManager.notify(WALLED_GARDEN_NOTIFICATION_ID, 1, notification); } else { notificationManager.cancel(WALLED_GARDEN_NOTIFICATION_ID, 1); } mWalledGardenNotificationShown = visible; } private void setDisabledNetworkNotificationVisible(boolean visible) { // If it should be hidden and it is already hidden, then noop if (!visible && !mDisabledNotificationShown) { return; } Resources r = Resources.getSystem(); NotificationManager notificationManager = (NotificationManager) mContext .getSystemService(Context.NOTIFICATION_SERVICE); if (visible) { CharSequence title = r.getText(R.string.wifi_watchdog_network_disabled); String msg = mConnectionInfo.getSSID() + r.getText(R.string.wifi_watchdog_network_disabled_detailed); Notification wifiDisabledWarning = new Notification.Builder(mContext) .setSmallIcon(R.drawable.stat_sys_warning) .setDefaults(Notification.DEFAULT_ALL) .setTicker(title) .setContentTitle(title) .setContentText(msg) .setContentIntent(PendingIntent.getActivity(mContext, 0, new Intent(WifiManager.ACTION_PICK_WIFI_NETWORK) .setFlags(Intent.FLAG_ACTIVITY_NEW_TASK), 0)) .setWhen(System.currentTimeMillis()) .setAutoCancel(true) .getNotification(); notificationManager.notify(DISABLED_NETWORK_NOTIFICATION_ID, 1, wifiDisabledWarning); } else { notificationManager.cancel(DISABLED_NETWORK_NOTIFICATION_ID, 1); } mDisabledNotificationShown = visible; } class DefaultState extends State { @Override public boolean processMessage(Message msg) { switch (msg.what) { case EVENT_WATCHDOG_SETTINGS_CHANGE: updateSettings(); if (DBG) { log("Updating wifi-watchdog secure settings"); } return HANDLED; } if (DBG) { log("Caught message " + msg.what + " in state " + getCurrentState().getName()); } return HANDLED; } } class WatchdogDisabledState extends State { @Override public boolean processMessage(Message msg) { switch (msg.what) { case EVENT_WATCHDOG_TOGGLED: if (isWatchdogEnabled()) transitionTo(mNotConnectedState); return HANDLED; } return NOT_HANDLED; } } class WatchdogEnabledState extends State { @Override public void enter() { resetWatchdogState(); mContext.registerReceiver(mBroadcastReceiver, mIntentFilter); if (DBG) log("WifiWatchdogService enabled"); } @Override public boolean processMessage(Message msg) { switch (msg.what) { case EVENT_WATCHDOG_TOGGLED: if (!isWatchdogEnabled()) transitionTo(mWatchdogDisabledState); return HANDLED; case EVENT_NETWORK_STATE_CHANGE: Intent stateChangeIntent = (Intent) msg.obj; NetworkInfo networkInfo = (NetworkInfo) stateChangeIntent.getParcelableExtra(WifiManager.EXTRA_NETWORK_INFO); setDisabledNetworkNotificationVisible(false); setWalledGardenNotificationVisible(false); switch (networkInfo.getState()) { case CONNECTED: WifiInfo wifiInfo = (WifiInfo) stateChangeIntent.getParcelableExtra(WifiManager.EXTRA_WIFI_INFO); if (wifiInfo == null) { loge("Connected --> WifiInfo object null!"); return HANDLED; } if (wifiInfo.getSSID() == null || wifiInfo.getBSSID() == null) { loge("Received wifiInfo object with null elts: " + wifiInfoToStr(wifiInfo)); return HANDLED; } initConnection(wifiInfo); mConnectionInfo = wifiInfo; mNetEventCounter++; if (mPoorNetworkDetectionEnabled) { updateBssids(); transitionTo(mDnsCheckingState); } else { transitionTo(mDelayWalledGardenState); } break; default: mNetEventCounter++; transitionTo(mNotConnectedState); break; } return HANDLED; case EVENT_WIFI_RADIO_STATE_CHANGE: if ((Integer) msg.obj == WifiManager.WIFI_STATE_DISABLING) { if (DBG) log("WifiStateDisabling -- Resetting WatchdogState"); resetWatchdogState(); mNetEventCounter++; transitionTo(mNotConnectedState); } return HANDLED; } return NOT_HANDLED; } /** * @param wifiInfo Info object with non-null ssid and bssid */ private void initConnection(WifiInfo wifiInfo) { if (DBG) { log("Connected:: old " + wifiInfoToStr(mConnectionInfo) + " ==> new " + wifiInfoToStr(wifiInfo)); } if (mConnectionInfo == null || !wifiInfo.getSSID().equals(mConnectionInfo.getSSID())) { resetWatchdogState(); } else if (!wifiInfo.getBSSID().equals(mConnectionInfo.getBSSID())) { mDisableAPNextFailure = false; } } @Override public void exit() { mContext.unregisterReceiver(mBroadcastReceiver); if (DBG) log("WifiWatchdogService disabled"); } } class NotConnectedState extends State { } class ConnectedState extends State { @Override public boolean processMessage(Message msg) { switch (msg.what) { case EVENT_SCAN_RESULTS_AVAILABLE: if (mPoorNetworkDetectionEnabled) { updateBssids(); } return HANDLED; case EVENT_WATCHDOG_SETTINGS_CHANGE: updateSettings(); if (mPoorNetworkDetectionEnabled) { transitionTo(mOnlineWatchState); } else { transitionTo(mOnlineState); } return HANDLED; } return NOT_HANDLED; } } class DnsCheckingState extends State { List mDnsList; int[] dnsCheckSuccesses; String dnsCheckLogStr; String[] dnsResponseStrs; /** Keeps track of active dns pings. Map is from pingID to index in mDnsList */ HashMap idDnsMap = new HashMap(); @Override public void enter() { mDnsList = mDnsPinger.getDnsList(); int numDnses = mDnsList.size(); dnsCheckSuccesses = new int[numDnses]; dnsResponseStrs = new String[numDnses]; for (int i = 0; i < numDnses; i++) dnsResponseStrs[i] = ""; if (DBG) { dnsCheckLogStr = String.format("Pinging %s on ssid [%s]: ", mDnsList, mConnectionInfo.getSSID()); log(dnsCheckLogStr); } idDnsMap.clear(); for (int i=0; i < mNumDnsPings; i++) { for (int j = 0; j < numDnses; j++) { idDnsMap.put(mDnsPinger.pingDnsAsync(mDnsList.get(j), mDnsPingTimeoutMs, DNS_START_DELAY_MS + DNS_INTRATEST_PING_INTERVAL_MS * i), j); } } } @Override public boolean processMessage(Message msg) { if (msg.what != DnsPinger.DNS_PING_RESULT) { return NOT_HANDLED; } int pingID = msg.arg1; int pingResponseTime = msg.arg2; Integer dnsServerId = idDnsMap.get(pingID); if (dnsServerId == null) { loge("Received a Dns response with unknown ID!"); return HANDLED; } idDnsMap.remove(pingID); if (pingResponseTime >= 0) dnsCheckSuccesses[dnsServerId]++; if (DBG) { if (pingResponseTime >= 0) { dnsResponseStrs[dnsServerId] += "|" + pingResponseTime; } else { dnsResponseStrs[dnsServerId] += "|x"; } } /** * After a full ping count, if we have more responses than this * cutoff, the outcome is success; else it is 'failure'. */ /** * Our final success count will be at least this big, so we're * guaranteed to succeed. */ if (dnsCheckSuccesses[dnsServerId] >= mMinDnsResponses) { // DNS CHECKS OK, NOW WALLED GARDEN if (DBG) { log(makeLogString() + " SUCCESS"); } if (!shouldCheckWalledGarden()) { transitionTo(mOnlineWatchState); return HANDLED; } transitionTo(mDelayWalledGardenState); return HANDLED; } if (idDnsMap.isEmpty()) { if (DBG) { log(makeLogString() + " FAILURE"); } transitionTo(mDnsCheckFailureState); return HANDLED; } return HANDLED; } private String makeLogString() { String logStr = dnsCheckLogStr; for (String respStr : dnsResponseStrs) logStr += " [" + respStr + "]"; return logStr; } @Override public void exit() { mDnsPinger.cancelPings(); } private boolean shouldCheckWalledGarden() { if (!mWalledGardenTestEnabled) { if (DBG) log("Skipping walled garden check - disabled"); return false; } long waitTime = waitTime(mWalledGardenIntervalMs, mLastWalledGardenCheckTime); if (waitTime > 0) { if (DBG) { log("Skipping walled garden check - wait " + waitTime + " ms."); } return false; } return true; } } class DelayWalledGardenState extends State { @Override public void enter() { sendMessageDelayed(MESSAGE_DELAYED_WALLED_GARDEN_CHECK, WALLED_GARDEN_START_DELAY_MS); } @Override public boolean processMessage(Message msg) { switch (msg.what) { case MESSAGE_DELAYED_WALLED_GARDEN_CHECK: mLastWalledGardenCheckTime = SystemClock.elapsedRealtime(); if (isWalledGardenConnection()) { if (DBG) log("Walled garden test complete - walled garden detected"); transitionTo(mWalledGardenState); } else { if (DBG) log("Walled garden test complete - online"); if (mPoorNetworkDetectionEnabled) { transitionTo(mOnlineWatchState); } else { transitionTo(mOnlineState); } } return HANDLED; default: return NOT_HANDLED; } } } class OnlineWatchState extends State { /** * Signals a short-wait message is enqueued for the current 'guard' counter */ boolean unstableSignalChecks = false; /** * The signal is unstable. We should enqueue a short-wait check, if one is enqueued * already */ boolean signalUnstable = false; /** * A monotonic counter to ensure that at most one check message will be processed from any * set of check messages currently enqueued. Avoids duplicate checks when a low-signal * event is observed. */ int checkGuard = 0; Long lastCheckTime = null; /** Keeps track of dns pings. Map is from pingID to InetAddress used for ping */ HashMap pingInfoMap = new HashMap(); @Override public void enter() { lastCheckTime = SystemClock.elapsedRealtime(); signalUnstable = false; checkGuard++; unstableSignalChecks = false; pingInfoMap.clear(); triggerSingleDnsCheck(); } @Override public boolean processMessage(Message msg) { switch (msg.what) { case EVENT_RSSI_CHANGE: if (msg.arg1 != mNetEventCounter) { if (DBG) { log("Rssi change message out of sync, ignoring"); } return HANDLED; } int newRssi = msg.arg2; signalUnstable = !rssiStrengthAboveCutoff(newRssi); if (DBG) { log("OnlineWatchState:: new rssi " + newRssi + " --> level " + WifiManager.calculateSignalLevel(newRssi, WIFI_SIGNAL_LEVELS)); } if (signalUnstable && !unstableSignalChecks) { if (DBG) { log("Sending triggered check msg"); } triggerSingleDnsCheck(); } return HANDLED; case MESSAGE_SINGLE_DNS_CHECK: if (msg.arg1 != checkGuard) { if (DBG) { log("Single check msg out of sync, ignoring."); } return HANDLED; } lastCheckTime = SystemClock.elapsedRealtime(); pingInfoMap.clear(); for (InetAddress curDns: mDnsPinger.getDnsList()) { pingInfoMap.put(mDnsPinger.pingDnsAsync(curDns, mDnsPingTimeoutMs, 0), curDns); } return HANDLED; case DnsPinger.DNS_PING_RESULT: InetAddress curDnsServer = pingInfoMap.get(msg.arg1); if (curDnsServer == null) { return HANDLED; } pingInfoMap.remove(msg.arg1); int responseTime = msg.arg2; if (responseTime >= 0) { if (DBG) { log("Single DNS ping OK. Response time: " + responseTime + " from DNS " + curDnsServer); } pingInfoMap.clear(); checkGuard++; unstableSignalChecks = false; triggerSingleDnsCheck(); } else { if (pingInfoMap.isEmpty()) { if (DBG) { log("Single dns ping failure. All dns servers failed, " + "starting full checks."); } transitionTo(mDnsCheckingState); } } return HANDLED; } return NOT_HANDLED; } @Override public void exit() { mDnsPinger.cancelPings(); } /** * Times a dns check with an interval based on {@link #signalUnstable} */ private void triggerSingleDnsCheck() { long waitInterval; if (signalUnstable) { waitInterval = mDnsCheckShortIntervalMs; unstableSignalChecks = true; } else { waitInterval = mDnsCheckLongIntervalMs; } sendMessageDelayed(obtainMessage(MESSAGE_SINGLE_DNS_CHECK, checkGuard, 0), waitTime(waitInterval, lastCheckTime)); } } /* Child state of ConnectedState indicating that we are online * and there is nothing to do */ class OnlineState extends State { } class DnsCheckFailureState extends State { @Override public void enter() { mNumCheckFailures++; obtainMessage(MESSAGE_HANDLE_BAD_AP, mNetEventCounter, 0).sendToTarget(); } @Override public boolean processMessage(Message msg) { if (msg.what != MESSAGE_HANDLE_BAD_AP) { return NOT_HANDLED; } if (msg.arg1 != mNetEventCounter) { if (DBG) { log("Msg out of sync, ignoring..."); } return HANDLED; } if (mDisableAPNextFailure || mNumCheckFailures >= mBssids.size() || mNumCheckFailures >= mMaxSsidBlacklists) { if (sWifiOnly) { log("Would disable bad network, but device has no mobile data!" + " Going idle..."); // This state should be called idle -- will be changing flow. transitionTo(mNotConnectedState); return HANDLED; } // TODO : Unban networks if they had low signal ? log("Disabling current SSID " + wifiInfoToStr(mConnectionInfo) + ". " + "numCheckFailures " + mNumCheckFailures + ", numAPs " + mBssids.size()); int networkId = mConnectionInfo.getNetworkId(); if (!mHasConnectedWifiManager) { mWifiManager.asyncConnect(mContext, getHandler()); mHasConnectedWifiManager = true; } mWifiManager.disableNetwork(networkId, WifiConfiguration.DISABLED_DNS_FAILURE); if (mShowDisabledNotification && mConnectionInfo.isExplicitConnect()) { setDisabledNetworkNotificationVisible(true); } transitionTo(mNotConnectedState); } else { log("Blacklisting current BSSID. " + wifiInfoToStr(mConnectionInfo) + "numCheckFailures " + mNumCheckFailures + ", numAPs " + mBssids.size()); mWifiManager.addToBlacklist(mConnectionInfo.getBSSID()); mWifiManager.reassociate(); transitionTo(mBlacklistedApState); } return HANDLED; } } class WalledGardenState extends State { @Override public void enter() { obtainMessage(MESSAGE_HANDLE_WALLED_GARDEN, mNetEventCounter, 0).sendToTarget(); } @Override public boolean processMessage(Message msg) { if (msg.what != MESSAGE_HANDLE_WALLED_GARDEN) { return NOT_HANDLED; } if (msg.arg1 != mNetEventCounter) { if (DBG) { log("WalledGardenState::Msg out of sync, ignoring..."); } return HANDLED; } setWalledGardenNotificationVisible(true); if (mPoorNetworkDetectionEnabled) { transitionTo(mOnlineWatchState); } else { transitionTo(mOnlineState); } return HANDLED; } } class BlacklistedApState extends State { @Override public void enter() { mDisableAPNextFailure = true; sendMessageDelayed(obtainMessage(MESSAGE_NETWORK_FOLLOWUP, mNetEventCounter, 0), mBlacklistFollowupIntervalMs); } @Override public boolean processMessage(Message msg) { if (msg.what != MESSAGE_NETWORK_FOLLOWUP) { return NOT_HANDLED; } if (msg.arg1 != mNetEventCounter) { if (DBG) { log("BlacklistedApState::Msg out of sync, ignoring..."); } return HANDLED; } transitionTo(mDnsCheckingState); return HANDLED; } } /** * Convenience function for retrieving a single secure settings value * as a string with a default value. * * @param cr The ContentResolver to access. * @param name The name of the setting to retrieve. * @param def Value to return if the setting is not defined. * * @return The setting's current value, or 'def' if it is not defined */ private static String getSettingsStr(ContentResolver cr, String name, String def) { String v = Settings.Secure.getString(cr, name); return v != null ? v : def; } /** * Convenience function for retrieving a single secure settings value * as a boolean. Note that internally setting values are always * stored as strings; this function converts the string to a boolean * for you. The default value will be returned if the setting is * not defined or not a valid boolean. * * @param cr The ContentResolver to access. * @param name The name of the setting to retrieve. * @param def Value to return if the setting is not defined. * * @return The setting's current value, or 'def' if it is not defined * or not a valid boolean. */ private static boolean getSettingsBoolean(ContentResolver cr, String name, boolean def) { return Settings.Secure.getInt(cr, name, def ? 1 : 0) == 1; } /** * Convenience function for updating a single settings value as an * integer. This will either create a new entry in the table if the * given name does not exist, or modify the value of the existing row * with that name. Note that internally setting values are always * stored as strings, so this function converts the given value to a * string before storing it. * * @param cr The ContentResolver to access. * @param name The name of the setting to modify. * @param value The new value for the setting. * @return true if the value was set, false on database errors */ private static boolean putSettingsBoolean(ContentResolver cr, String name, boolean value) { return Settings.Secure.putInt(cr, name, value ? 1 : 0); } private void log(String s) { Log.d(TAG, s); } private void loge(String s) { Log.e(TAG, s); } }