WifiWatchdog rewrite to formal statemachine
Rewrote wifiwatchdog service to use net.statemachine
Change-Id: Id6fd42b13192ac2e99f842ff50e9edff1696675d
diff --git a/core/java/com/android/internal/util/Protocol.java b/core/java/com/android/internal/util/Protocol.java
index b754d94..69b80d9 100644
--- a/core/java/com/android/internal/util/Protocol.java
+++ b/core/java/com/android/internal/util/Protocol.java
@@ -40,6 +40,7 @@
/** Non system protocols */
public static final int BASE_WIFI = 0x00020000;
+ public static final int BASE_WIFI_WATCHDOG = 0x00021000;
public static final int BASE_DHCP = 0x00030000;
public static final int BASE_DATA_CONNECTION = 0x00040000;
public static final int BASE_DATA_CONNECTION_AC = 0x00041000;
diff --git a/services/java/com/android/server/WifiService.java b/services/java/com/android/server/WifiService.java
index 5f0922e..7112553 100644
--- a/services/java/com/android/server/WifiService.java
+++ b/services/java/com/android/server/WifiService.java
@@ -35,8 +35,8 @@
import android.net.wifi.WifiManager;
import android.net.wifi.WifiStateMachine;
import android.net.wifi.WifiConfiguration;
+import android.net.wifi.WifiWatchdogStateMachine;
import android.net.wifi.WifiConfiguration.KeyMgmt;
-import android.net.wifi.WifiWatchdogService;
import android.net.wifi.WpsConfiguration;
import android.net.wifi.WpsResult;
import android.net.ConnectivityManager;
@@ -343,7 +343,7 @@
* Protected by mWifiStateTracker lock.
*/
private final WorkSource mTmpWorkSource = new WorkSource();
- private WifiWatchdogService mWifiWatchdogService;
+ private WifiWatchdogStateMachine mWifiWatchdogStateMachine;
WifiService(Context context) {
mContext = context;
@@ -434,8 +434,9 @@
(wifiEnabled ? "enabled" : "disabled"));
setWifiEnabled(wifiEnabled);
- //TODO: as part of WWS refactor, create only when needed
- mWifiWatchdogService = new WifiWatchdogService(mContext);
+ mWifiWatchdogStateMachine = WifiWatchdogStateMachine.
+ makeWifiWatchdogStateMachine(mContext);
+
}
private boolean testAndClearWifiSavedState() {
@@ -1162,8 +1163,8 @@
mLocks.dump(pw);
pw.println();
- pw.println("WifiWatchdogService dump");
- mWifiWatchdogService.dump(pw);
+ pw.println("WifiWatchdogStateMachine dump");
+ mWifiWatchdogStateMachine.dump(pw);
}
private class WifiLock extends DeathRecipient {
diff --git a/wifi/java/android/net/wifi/WifiWatchdogService.java b/wifi/java/android/net/wifi/WifiWatchdogService.java
deleted file mode 100644
index bce4b3a..0000000
--- a/wifi/java/android/net/wifi/WifiWatchdogService.java
+++ /dev/null
@@ -1,765 +0,0 @@
-/*
- * Copyright (C) 2008 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.content.BroadcastReceiver;
-import android.content.ContentResolver;
-import android.content.Context;
-import android.content.Intent;
-import android.content.IntentFilter;
-import android.database.ContentObserver;
-import android.net.ConnectivityManager;
-import android.net.DnsPinger;
-import android.net.NetworkInfo;
-import android.net.Uri;
-import android.os.Handler;
-import android.os.HandlerThread;
-import android.os.Looper;
-import android.os.Message;
-import android.os.SystemClock;
-import android.provider.Settings;
-import android.text.TextUtils;
-import android.util.Slog;
-
-import java.io.BufferedInputStream;
-import java.io.IOException;
-import java.io.InputStream;
-import java.io.PrintWriter;
-import java.net.HttpURLConnection;
-import java.net.URL;
-import java.util.HashSet;
-import java.util.List;
-import java.util.Scanner;
-
-/**
- * {@link WifiWatchdogService} 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}.
- * <p>
- * 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.
- * <p>
- * On DNS success, the WatchdogService initiates a walled garden check via an
- * http get. A browser windows is activated if a walled garden is detected.
- *
- * @hide
- */
-public class WifiWatchdogService {
-
- private static final String WWS_TAG = "WifiWatchdogService";
-
- private static final boolean VDBG = true;
- private static final boolean DBG = true;
-
- // Used for verbose logging
- private String mDNSCheckLogStr;
-
- private Context mContext;
- private ContentResolver mContentResolver;
- private WifiManager mWifiManager;
-
- private WifiWatchdogHandler mHandler;
-
- private DnsPinger mDnsPinger;
-
- private IntentFilter mIntentFilter;
- private BroadcastReceiver mBroadcastReceiver;
- private boolean mBroadcastsEnabled;
-
- 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 MIN_LOW_SIGNAL_CHECK_INTERVAL = 2 * 60 * 1000;
- private static final long MIN_SINGLE_DNS_CHECK_INTERVAL = 10 * 60 * 1000;
- private static final long MIN_WALLED_GARDEN_INTERVAL = 15 * 60 * 1000;
-
- private static final int MAX_CHECKS_PER_SSID = 9;
- private static final int NUM_DNS_PINGS = 7;
- private static double MIN_RESPONSE_RATE = 0.50;
-
- // TODO : Adjust multiple DNS downward to 250 on repeated failure
- // private static final int MULTI_DNS_PING_TIMEOUT_MS = 250;
-
- private static final int DNS_PING_TIMEOUT_MS = 800;
- private static final long DNS_PING_INTERVAL = 250;
-
- private static final long BLACKLIST_FOLLOWUP_INTERVAL = 15 * 1000;
-
- private Status mStatus = new Status();
-
- private static class Status {
- String bssid = "";
- String ssid = "";
-
- HashSet<String> allBssids = new HashSet<String>();
- int numFullDNSchecks = 0;
-
- long lastSingleCheckTime = -24 * 60 * 60 * 1000;
- long lastWalledGardenCheckTime = -24 * 60 * 60 * 1000;
-
- WatchdogState state = WatchdogState.INACTIVE;
-
- // Info for dns check
- int dnsCheckTries = 0;
- int dnsCheckSuccesses = 0;
-
- public int signal = -200;
-
- }
-
- private enum WatchdogState {
- /**
- * Full DNS check in progress
- */
- DNS_FULL_CHECK,
-
- /**
- * Walled Garden detected, will pop up browser next round.
- */
- WALLED_GARDEN_DETECTED,
-
- /**
- * DNS failed, will blacklist/disable AP next round
- */
- DNS_CHECK_FAILURE,
-
- /**
- * Online or displaying walled garden auth page
- */
- CHECKS_COMPLETE,
-
- /**
- * Watchdog idle, network has been blacklisted or received disconnect
- * msg
- */
- INACTIVE,
-
- BLACKLISTED_AP
- }
-
- public WifiWatchdogService(Context context) {
- mContext = context;
- mContentResolver = context.getContentResolver();
- mWifiManager = (WifiManager) context.getSystemService(Context.WIFI_SERVICE);
- mDnsPinger = new DnsPinger("WifiWatchdogServer.DnsPinger", context,
- ConnectivityManager.TYPE_WIFI);
-
- HandlerThread handlerThread = new HandlerThread("WifiWatchdogServiceThread");
- handlerThread.start();
- mHandler = new WifiWatchdogHandler(handlerThread.getLooper());
-
- setupNetworkReceiver();
-
- // The content observer to listen needs a handler, which createThread
- // creates
- registerForSettingsChanges();
-
- // Start things off
- if (isWatchdogEnabled()) {
- mHandler.sendEmptyMessage(WifiWatchdogHandler.MESSAGE_CONTEXT_EVENT);
- }
- }
-
- /**
- *
- */
- 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)) {
- mHandler.sendMessage(mHandler.obtainMessage(
- WifiWatchdogHandler.MESSAGE_NETWORK_EVENT,
- intent.getParcelableExtra(WifiManager.EXTRA_NETWORK_INFO)
- ));
- } else if (action.equals(WifiManager.RSSI_CHANGED_ACTION)) {
- mHandler.sendEmptyMessage(WifiWatchdogHandler.RSSI_CHANGE_EVENT);
- } else if (action.equals(WifiManager.SCAN_RESULTS_AVAILABLE_ACTION)) {
- mHandler.sendEmptyMessage(WifiWatchdogHandler.SCAN_RESULTS_AVAILABLE);
- } else if (action.equals(WifiManager.WIFI_STATE_CHANGED_ACTION)) {
- mHandler.sendMessage(mHandler.obtainMessage(
- WifiWatchdogHandler.WIFI_STATE_CHANGE,
- intent.getIntExtra(WifiManager.EXTRA_WIFI_STATE, 4)));
- }
- }
- };
-
- 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 registerForSettingsChanges() {
- ContentObserver contentObserver = new ContentObserver(mHandler) {
- @Override
- public void onChange(boolean selfChange) {
- mHandler.sendEmptyMessage((WifiWatchdogHandler.MESSAGE_CONTEXT_EVENT));
- }
- };
-
- mContext.getContentResolver().registerContentObserver(
- Settings.Secure.getUriFor(Settings.Secure.WIFI_WATCHDOG_ON),
- false, contentObserver);
- }
-
- private void handleNewConnection() {
- WifiInfo wifiInfo = mWifiManager.getConnectionInfo();
- String newSsid = wifiInfo.getSSID();
- String newBssid = wifiInfo.getBSSID();
-
- if (VDBG) {
- Slog.v(WWS_TAG, String.format("handleConnected:: old (%s, %s) ==> new (%s, %s)",
- mStatus.ssid, mStatus.bssid, newSsid, newBssid));
- }
-
- if (TextUtils.isEmpty(newSsid) || TextUtils.isEmpty(newBssid)) {
- return;
- }
-
- if (!TextUtils.equals(mStatus.ssid, newSsid)) {
- mStatus = new Status();
- mStatus.ssid = newSsid;
- }
-
- mStatus.bssid = newBssid;
- mStatus.allBssids.add(newBssid);
- mStatus.signal = WifiManager.calculateSignalLevel(wifiInfo.getRssi(), WIFI_SIGNAL_LEVELS);
-
- initDnsFullCheck();
- }
-
- public void updateRssi() {
- WifiInfo wifiInfo = mWifiManager.getConnectionInfo();
- if (!TextUtils.equals(mStatus.ssid, wifiInfo.getSSID()) ||
- !TextUtils.equals(mStatus.bssid, wifiInfo.getBSSID())) {
- return;
- }
-
- mStatus.signal = WifiManager.calculateSignalLevel(wifiInfo.getRssi(), WIFI_SIGNAL_LEVELS);
- }
-
- /**
- * Single step in state machine
- */
- private void handleStateStep() {
- // Slog.v(WWS_TAG, "handleStateStep:: " + mStatus.state);
-
- switch (mStatus.state) {
- case DNS_FULL_CHECK:
- if (VDBG) {
- Slog.v(WWS_TAG, "DNS_FULL_CHECK: " + mDNSCheckLogStr);
- }
-
- long pingResponseTime = mDnsPinger.pingDns(mDnsPinger.getDns(),
- DNS_PING_TIMEOUT_MS);
-
- mStatus.dnsCheckTries++;
- if (pingResponseTime >= 0)
- mStatus.dnsCheckSuccesses++;
-
- if (DBG) {
- if (pingResponseTime >= 0) {
- mDNSCheckLogStr += " | " + pingResponseTime;
- } else {
- mDNSCheckLogStr += " | " + "x";
- }
- }
-
- switch (currentDnsCheckStatus()) {
- case SUCCESS:
- if (DBG) {
- Slog.d(WWS_TAG, mDNSCheckLogStr + " -- Success");
- }
- doWalledGardenCheck();
- break;
- case FAILURE:
- if (DBG) {
- Slog.d(WWS_TAG, mDNSCheckLogStr + " -- Failure");
- }
- mStatus.state = WatchdogState.DNS_CHECK_FAILURE;
- break;
- case INCOMPLETE:
- // Taking no action
- break;
- }
- break;
- case DNS_CHECK_FAILURE:
- WifiInfo wifiInfo = mWifiManager.getConnectionInfo();
- if (!mStatus.ssid.equals(wifiInfo.getSSID()) ||
- !mStatus.bssid.equals(wifiInfo.getBSSID())) {
- Slog.i(WWS_TAG, "handleState DNS_CHECK_FAILURE:: network has changed!");
- mStatus.state = WatchdogState.INACTIVE;
- break;
- }
-
- if (mStatus.numFullDNSchecks >= mStatus.allBssids.size() ||
- mStatus.numFullDNSchecks >= MAX_CHECKS_PER_SSID) {
- disableAP(wifiInfo);
- } else {
- blacklistAP();
- }
- break;
- case WALLED_GARDEN_DETECTED:
- popUpBrowser();
- mStatus.state = WatchdogState.CHECKS_COMPLETE;
- break;
- case BLACKLISTED_AP:
- WifiInfo wifiInfo2 = mWifiManager.getConnectionInfo();
- if (wifiInfo2.getSupplicantState() != SupplicantState.COMPLETED) {
- Slog.d(WWS_TAG,
- "handleState::BlacklistedAP - offline, but didn't get disconnect!");
- mStatus.state = WatchdogState.INACTIVE;
- break;
- }
- if (mStatus.bssid.equals(wifiInfo2.getBSSID())) {
- Slog.d(WWS_TAG, "handleState::BlacklistedAP - connected to same bssid");
- if (!handleSingleDnsCheck()) {
- disableAP(wifiInfo2);
- break;
- }
- }
-
- Slog.d(WWS_TAG, "handleState::BlacklistedAP - Simiulating a new connection");
- handleNewConnection();
- break;
- }
- }
-
- private void doWalledGardenCheck() {
- if (!isWalledGardenTestEnabled()) {
- if (VDBG)
- Slog.v(WWS_TAG, "Skipping walled garden check - disabled");
- mStatus.state = WatchdogState.CHECKS_COMPLETE;
- return;
- }
- long waitTime = waitTime(MIN_WALLED_GARDEN_INTERVAL,
- mStatus.lastWalledGardenCheckTime);
- if (waitTime > 0) {
- if (VDBG) {
- Slog.v(WWS_TAG, "Skipping walled garden check - wait " +
- waitTime + " ms.");
- }
- mStatus.state = WatchdogState.CHECKS_COMPLETE;
- return;
- }
-
- mStatus.lastWalledGardenCheckTime = SystemClock.elapsedRealtime();
- if (isWalledGardenConnection()) {
- if (DBG)
- Slog.d(WWS_TAG,
- "Walled garden test complete - walled garden detected");
- mStatus.state = WatchdogState.WALLED_GARDEN_DETECTED;
- } else {
- if (DBG)
- Slog.d(WWS_TAG, "Walled garden test complete - online");
- mStatus.state = WatchdogState.CHECKS_COMPLETE;
- }
- }
-
- private boolean handleSingleDnsCheck() {
- mStatus.lastSingleCheckTime = SystemClock.elapsedRealtime();
- long responseTime = mDnsPinger.pingDns(mDnsPinger.getDns(),
- DNS_PING_TIMEOUT_MS);
- if (DBG) {
- Slog.d(WWS_TAG, "Ran a single DNS ping. Response time: " + responseTime);
- }
- if (responseTime < 0) {
- return false;
- }
- return true;
-
- }
-
- /**
- * @return Delay in MS before next single DNS check can proceed.
- */
- private long timeToNextScheduledDNSCheck() {
- if (mStatus.signal > LOW_SIGNAL_CUTOFF) {
- return waitTime(MIN_SINGLE_DNS_CHECK_INTERVAL, mStatus.lastSingleCheckTime);
- } else {
- return waitTime(MIN_LOW_SIGNAL_CHECK_INTERVAL, mStatus.lastSingleCheckTime);
- }
- }
-
- /**
- * 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()
- * @return non negative time to wait
- */
- private static long waitTime(long interval, long lastTime) {
- long wait = interval + lastTime - SystemClock.elapsedRealtime();
- return wait > 0 ? wait : 0;
- }
-
- private void popUpBrowser() {
- Uri uri = Uri.parse("http://www.google.com");
- Intent intent = new Intent(Intent.ACTION_VIEW, uri);
- intent.setFlags(Intent.FLAG_ACTIVITY_BROUGHT_TO_FRONT |
- Intent.FLAG_ACTIVITY_NEW_TASK);
- mContext.startActivity(intent);
- }
-
- private void disableAP(WifiInfo info) {
- // TODO : Unban networks if they had low signal ?
- Slog.i(WWS_TAG, String.format("Disabling current SSID, %s [bssid %s]. " +
- "numChecks %d, numAPs %d", mStatus.ssid, mStatus.bssid,
- mStatus.numFullDNSchecks, mStatus.allBssids.size()));
- mWifiManager.disableNetwork(info.getNetworkId());
- mStatus.state = WatchdogState.INACTIVE;
- }
-
- private void blacklistAP() {
- Slog.i(WWS_TAG, String.format("Blacklisting current BSSID %s [ssid %s]. " +
- "numChecks %d, numAPs %d", mStatus.bssid, mStatus.ssid,
- mStatus.numFullDNSchecks, mStatus.allBssids.size()));
-
- mWifiManager.addToBlacklist(mStatus.bssid);
- mWifiManager.reassociate();
- mStatus.state = WatchdogState.BLACKLISTED_AP;
- }
-
- /**
- * Checks the scan for new BBIDs using current mSsid
- */
- private void updateBssids() {
- String curSsid = mStatus.ssid;
- HashSet<String> bssids = mStatus.allBssids;
- List<ScanResult> results = mWifiManager.getScanResults();
- int oldNumBssids = bssids.size();
-
- if (results == null) {
- if (VDBG) {
- Slog.v(WWS_TAG, "updateBssids: Got null scan results!");
- }
- return;
- }
-
- for (ScanResult result : results) {
- if (result != null && curSsid.equals(result.SSID))
- bssids.add(result.BSSID);
- }
-
- // if (VDBG && bssids.size() - oldNumBssids > 0) {
- // Slog.v(WWS_TAG,
- // String.format("updateBssids:: Found %d new APs (total %d) on SSID %s",
- // bssids.size() - oldNumBssids, bssids.size(), curSsid));
- // }
- }
-
- enum DnsCheckStatus {
- SUCCESS,
- FAILURE,
- INCOMPLETE
- }
-
- /**
- * Computes the current results of the dns check, ends early if outcome is
- * assured.
- */
- private DnsCheckStatus currentDnsCheckStatus() {
- /**
- * After a full ping count, if we have more responses than this cutoff,
- * the outcome is success; else it is 'failure'.
- */
- double pingResponseCutoff = MIN_RESPONSE_RATE * NUM_DNS_PINGS;
- int remainingChecks = NUM_DNS_PINGS - mStatus.dnsCheckTries;
-
- /**
- * Our final success count will be at least this big, so we're
- * guaranteed to succeed.
- */
- if (mStatus.dnsCheckSuccesses >= pingResponseCutoff) {
- return DnsCheckStatus.SUCCESS;
- }
-
- /**
- * Our final count will be at most the current count plus the remaining
- * pings - we're guaranteed to fail.
- */
- if (remainingChecks + mStatus.dnsCheckSuccesses < pingResponseCutoff) {
- return DnsCheckStatus.FAILURE;
- }
-
- return DnsCheckStatus.INCOMPLETE;
- }
-
- private void initDnsFullCheck() {
- if (DBG) {
- Slog.d(WWS_TAG, "Starting DNS pings at " + SystemClock.elapsedRealtime());
- }
- mStatus.numFullDNSchecks++;
- mStatus.dnsCheckSuccesses = 0;
- mStatus.dnsCheckTries = 0;
- mStatus.state = WatchdogState.DNS_FULL_CHECK;
-
- if (DBG) {
- mDNSCheckLogStr = String.format("Dns Check %d. Pinging %s on ssid [%s]: ",
- mStatus.numFullDNSchecks, mDnsPinger.getDns(),
- mStatus.ssid);
- }
- }
-
- /**
- * 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() {
- InputStream in = null;
- HttpURLConnection urlConnection = null;
- try {
- URL url = new URL(getWalledGardenUrl());
- urlConnection = (HttpURLConnection) url.openConnection();
- in = new BufferedInputStream(urlConnection.getInputStream());
- Scanner scanner = new Scanner(in);
- if (scanner.findInLine(getWalledGardenPattern()) != null) {
- return false;
- } else {
- return true;
- }
- } catch (IOException e) {
- return false;
- } finally {
- if (in != null) {
- try {
- in.close();
- } catch (IOException e) {
- }
- }
- if (urlConnection != null)
- urlConnection.disconnect();
- }
- }
-
- /**
- * There is little logic inside this class, instead methods of the form
- * "handle___" are called in the main {@link WifiWatchdogService}.
- */
- private class WifiWatchdogHandler extends Handler {
- /**
- * Major network event, object is NetworkInfo
- */
- static final int MESSAGE_NETWORK_EVENT = 1;
- /**
- * Change in settings, no object
- */
- static final int MESSAGE_CONTEXT_EVENT = 2;
-
- /**
- * Change in signal strength
- */
- static final int RSSI_CHANGE_EVENT = 3;
- static final int SCAN_RESULTS_AVAILABLE = 4;
-
- static final int WIFI_STATE_CHANGE = 5;
-
- /**
- * Single step of state machine. One DNS check, or one WalledGarden
- * check, or one external action. We separate out external actions to
- * increase chance of detecting that a check failure is caused by change
- * in network status. Messages should have an arg1 which to sync status
- * messages.
- */
- static final int CHECK_SEQUENCE_STEP = 10;
- static final int SINGLE_DNS_CHECK = 11;
-
- /**
- * @param looper
- */
- public WifiWatchdogHandler(Looper looper) {
- super(looper);
- }
-
- boolean singleCheckQueued = false;
- long queuedSingleDnsCheckArrival;
-
- /**
- * Sends a singleDnsCheck message with shortest time - guards against
- * multiple.
- */
- private boolean queueSingleDnsCheck() {
- long delay = timeToNextScheduledDNSCheck();
- long newArrival = delay + SystemClock.elapsedRealtime();
- if (singleCheckQueued && queuedSingleDnsCheckArrival <= newArrival)
- return true;
- queuedSingleDnsCheckArrival = newArrival;
- singleCheckQueued = true;
- removeMessages(SINGLE_DNS_CHECK);
- return sendMessageDelayed(obtainMessage(SINGLE_DNS_CHECK), delay);
- }
-
- boolean checkSequenceQueued = false;
- long queuedCheckSequenceArrival;
-
- /**
- * Sends a state_machine_step message if the delay requested is lower
- * than the current delay.
- */
- private boolean sendCheckSequenceStep(long delay) {
- long newArrival = delay + SystemClock.elapsedRealtime();
- if (checkSequenceQueued && queuedCheckSequenceArrival <= newArrival)
- return true;
- queuedCheckSequenceArrival = newArrival;
- checkSequenceQueued = true;
- removeMessages(CHECK_SEQUENCE_STEP);
- return sendMessageDelayed(obtainMessage(CHECK_SEQUENCE_STEP), delay);
- }
-
- @Override
- public void handleMessage(Message msg) {
- switch (msg.what) {
- case CHECK_SEQUENCE_STEP:
- checkSequenceQueued = false;
- handleStateStep();
- if (mStatus.state == WatchdogState.CHECKS_COMPLETE) {
- queueSingleDnsCheck();
- } else if (mStatus.state == WatchdogState.DNS_FULL_CHECK) {
- sendCheckSequenceStep(DNS_PING_INTERVAL);
- } else if (mStatus.state == WatchdogState.BLACKLISTED_AP) {
- sendCheckSequenceStep(BLACKLIST_FOLLOWUP_INTERVAL);
- } else if (mStatus.state != WatchdogState.INACTIVE) {
- sendCheckSequenceStep(0);
- }
- return;
- case MESSAGE_NETWORK_EVENT:
- if (!mBroadcastsEnabled) {
- Slog.e(WWS_TAG,
- "MessageNetworkEvent - WatchdogService not enabled... returning");
- return;
- }
- NetworkInfo info = (NetworkInfo) msg.obj;
- switch (info.getState()) {
- case DISCONNECTED:
- mStatus.state = WatchdogState.INACTIVE;
- return;
- case CONNECTED:
- handleNewConnection();
- sendCheckSequenceStep(0);
- }
- return;
- case SINGLE_DNS_CHECK:
- singleCheckQueued = false;
- if (mStatus.state != WatchdogState.CHECKS_COMPLETE) {
- Slog.d(WWS_TAG, "Single check returning, curState: " + mStatus.state);
- break;
- }
-
- if (!handleSingleDnsCheck()) {
- initDnsFullCheck();
- sendCheckSequenceStep(0);
- } else {
- queueSingleDnsCheck();
- }
-
- break;
- case RSSI_CHANGE_EVENT:
- updateRssi();
- if (mStatus.state == WatchdogState.CHECKS_COMPLETE)
- queueSingleDnsCheck();
- break;
- case SCAN_RESULTS_AVAILABLE:
- updateBssids();
- break;
- case WIFI_STATE_CHANGE:
- if ((Integer) msg.obj == WifiManager.WIFI_STATE_DISABLING) {
- Slog.i(WWS_TAG, "WifiStateDisabling -- Resetting WatchdogState");
- mStatus = new Status();
- }
- break;
- case MESSAGE_CONTEXT_EVENT:
- if (isWatchdogEnabled() && !mBroadcastsEnabled) {
- mContext.registerReceiver(mBroadcastReceiver, mIntentFilter);
- mBroadcastsEnabled = true;
- Slog.i(WWS_TAG, "WifiWatchdogService enabled");
- } else if (!isWatchdogEnabled() && mBroadcastsEnabled) {
- mContext.unregisterReceiver(mBroadcastReceiver);
- removeMessages(SINGLE_DNS_CHECK);
- removeMessages(CHECK_SEQUENCE_STEP);
- mBroadcastsEnabled = false;
- Slog.i(WWS_TAG, "WifiWatchdogService disabled");
- }
- break;
- }
- }
- }
-
- public void dump(PrintWriter pw) {
- pw.print("WatchdogStatus: ");
- pw.print("State " + mStatus.state);
- pw.println(", network [" + mStatus.ssid + ", " + mStatus.bssid + "]");
- pw.print("checkCount " + mStatus.numFullDNSchecks);
- pw.println(", bssids: " + mStatus.allBssids);
- pw.print(", hasCheckMessages? " +
- mHandler.hasMessages(WifiWatchdogHandler.CHECK_SEQUENCE_STEP));
- pw.println(" hasSingleCheckMessages? " +
- mHandler.hasMessages(WifiWatchdogHandler.SINGLE_DNS_CHECK));
- pw.println("DNS check log str: " + mDNSCheckLogStr);
- pw.println("lastSingleCheck: " + mStatus.lastSingleCheckTime);
- }
-
- /**
- * @see android.provider.Settings.Secure#WIFI_WATCHDOG_WALLED_GARDEN_TEST_ENABLED
- */
- private Boolean isWalledGardenTestEnabled() {
- return Settings.Secure.getInt(mContentResolver,
- Settings.Secure.WIFI_WATCHDOG_WALLED_GARDEN_TEST_ENABLED, 1) == 1;
- }
-
- /**
- * @see android.provider.Settings.Secure#WIFI_WATCHDOG_WALLED_GARDEN_URL
- */
- private String getWalledGardenUrl() {
- String url = Settings.Secure.getString(mContentResolver,
- Settings.Secure.WIFI_WATCHDOG_WALLED_GARDEN_URL);
- if (TextUtils.isEmpty(url))
- return "http://www.google.com/";
- return url;
- }
-
- /**
- * @see android.provider.Settings.Secure#WIFI_WATCHDOG_WALLED_GARDEN_PATTERN
- */
- private String getWalledGardenPattern() {
- String pattern = Settings.Secure.getString(mContentResolver,
- Settings.Secure.WIFI_WATCHDOG_WALLED_GARDEN_PATTERN);
- if (TextUtils.isEmpty(pattern))
- return "<title>.*Google.*</title>";
- return pattern;
- }
-
- /**
- * @see android.provider.Settings.Secure#WIFI_WATCHDOG_ON
- */
- private boolean isWatchdogEnabled() {
- return Settings.Secure.getInt(mContentResolver,
- Settings.Secure.WIFI_WATCHDOG_ON, 1) == 1;
- }
-}
diff --git a/wifi/java/android/net/wifi/WifiWatchdogStateMachine.java b/wifi/java/android/net/wifi/WifiWatchdogStateMachine.java
new file mode 100644
index 0000000..0eb73b7
--- /dev/null
+++ b/wifi/java/android/net/wifi/WifiWatchdogStateMachine.java
@@ -0,0 +1,825 @@
+/*
+ * 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.content.BroadcastReceiver;
+import android.content.ContentResolver;
+import android.content.Context;
+import android.content.Intent;
+import android.content.IntentFilter;
+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.provider.Settings;
+import android.text.TextUtils;
+import android.util.Slog;
+
+import com.android.internal.util.Protocol;
+import com.android.internal.util.State;
+import com.android.internal.util.StateMachine;
+
+import java.io.BufferedInputStream;
+import java.io.IOException;
+import java.io.InputStream;
+import java.io.PrintWriter;
+import java.net.HttpURLConnection;
+import java.net.URL;
+import java.util.HashSet;
+import java.util.List;
+import java.util.Scanner;
+
+/**
+ * {@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}.
+ * <p>
+ * 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.
+ * <p>
+ * 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 VDBG = false;
+ private static final boolean DBG = true;
+ private static final String WWSM_TAG = "WifiWatchdogStateMachine";
+
+ 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 = 1;
+
+ private static final long MIN_LOW_SIGNAL_CHECK_INTERVAL_MS = 2 * 60 * 1000;
+ private static final long MIN_SINGLE_DNS_CHECK_INTERVAL_MS = 10 * 60 * 1000;
+ private static final long MIN_WALLED_GARDEN_INTERVAL_MS = 30 * 60 * 1000;
+
+ private static final int MAX_CHECKS_PER_SSID = 7;
+ private static final int NUM_DNS_PINGS = 5;
+ private static final double MIN_DNS_RESPONSE_RATE = 0.50;
+
+ private static final int DNS_PING_TIMEOUT_MS = 800;
+ private static final long DNS_PING_INTERVAL_MS = 100;
+
+ private static final long BLACKLIST_FOLLOWUP_INTERVAL_MS = 15 * 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 MESSAGE_CHECK_STEP = BASE + 100;
+ private static final int MESSAGE_HANDLE_WALLED_GARDEN = BASE + 101;
+ private static final int MESSAGE_HANDLE_BAD_AP = BASE + 102;
+ /**
+ * arg1 == mOnlineWatchState.checkCount
+ */
+ private static final int MESSAGE_SINGLE_DNS_CHECK = BASE + 103;
+ private static final int MESSAGE_NETWORK_FOLLOWUP = 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 DnsCheckFailureState mDnsCheckFailureState = new DnsCheckFailureState();
+ private WalledGardenState mWalledGardenState = new WalledGardenState();
+ private BlacklistedApState mBlacklistedApState = new BlacklistedApState();
+
+ /**
+ * The {@link WifiInfo} object passed to WWSM on network broadcasts
+ */
+ private WifiInfo mInitialConnInfo;
+ private int mNetEventCounter = 0;
+
+ /**
+ * Currently maintained but not used, TODO
+ */
+ private HashSet<String> mBssids = new HashSet<String>();
+ private int mNumFullDNSchecks = 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;
+
+ /**
+ * STATE MAP
+ * Default
+ * / \
+ * Disabled Enabled
+ * / \
+ * Disconnected Connected
+ * /---------\
+ * (all other states)
+ */
+ private WifiWatchdogStateMachine(Context context) {
+ super(WWSM_TAG);
+ mContext = context;
+ mContentResolver = context.getContentResolver();
+ mWifiManager = (WifiManager) context.getSystemService(Context.WIFI_SERVICE);
+ mDnsPinger = new DnsPinger("WifiWatchdogServer.DnsPinger", context,
+ ConnectivityManager.TYPE_WIFI);
+
+ setupNetworkReceiver();
+
+ // The content observer to listen needs a handler
+ registerForSettingsChanges();
+ addState(mDefaultState);
+ addState(mWatchdogDisabledState, mDefaultState);
+ addState(mWatchdogEnabledState, mDefaultState);
+ addState(mNotConnectedState, mWatchdogEnabledState);
+ addState(mConnectedState, mWatchdogEnabledState);
+ addState(mDnsCheckingState, mConnectedState);
+ addState(mDnsCheckFailureState, mConnectedState);
+ addState(mWalledGardenState, mConnectedState);
+ addState(mBlacklistedApState, mConnectedState);
+ addState(mOnlineWatchState, mConnectedState);
+
+ setInitialState(mWatchdogDisabledState);
+ }
+
+ public static WifiWatchdogStateMachine makeWifiWatchdogStateMachine(Context context) {
+ 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 registerForSettingsChanges() {
+ 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);
+ }
+
+ /**
+ * 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() {
+ InputStream in = null;
+ HttpURLConnection urlConnection = null;
+ try {
+ URL url = new URL(getWalledGardenUrl());
+ urlConnection = (HttpURLConnection) url.openConnection();
+ in = new BufferedInputStream(urlConnection.getInputStream());
+ Scanner scanner = new Scanner(in);
+ if (scanner.findInLine(getWalledGardenPattern()) != null) {
+ return false;
+ } else {
+ return true;
+ }
+ } catch (IOException e) {
+ return false;
+ } finally {
+ if (in != null) {
+ try {
+ in.close();
+ } catch (IOException e) {
+ }
+ }
+ 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 [" + mInitialConnInfo + "]");
+ pw.print("checkCount " + mNumFullDNSchecks);
+ pw.println(", bssids: " + mBssids);
+ pw.println("lastSingleCheck: " + mOnlineWatchState.lastCheckTime);
+ }
+
+ /**
+ * @see android.provider.Settings.Secure#WIFI_WATCHDOG_WALLED_GARDEN_TEST_ENABLED
+ */
+ private Boolean isWalledGardenTestEnabled() {
+ return Settings.Secure.getInt(mContentResolver,
+ Settings.Secure.WIFI_WATCHDOG_WALLED_GARDEN_TEST_ENABLED, 1) == 1;
+ }
+
+ /**
+ * @see android.provider.Settings.Secure#WIFI_WATCHDOG_WALLED_GARDEN_URL
+ */
+ private String getWalledGardenUrl() {
+ String url = Settings.Secure.getString(mContentResolver,
+ Settings.Secure.WIFI_WATCHDOG_WALLED_GARDEN_URL);
+ if (TextUtils.isEmpty(url))
+ return "http://www.google.com/";
+ return url;
+ }
+
+ /**
+ * @see android.provider.Settings.Secure#WIFI_WATCHDOG_WALLED_GARDEN_PATTERN
+ */
+ private String getWalledGardenPattern() {
+ String pattern = Settings.Secure.getString(mContentResolver,
+ Settings.Secure.WIFI_WATCHDOG_WALLED_GARDEN_PATTERN);
+ if (TextUtils.isEmpty(pattern))
+ return "<title>.*Google.*</title>";
+ return pattern;
+ }
+
+ /**
+ * @see android.provider.Settings.Secure#WIFI_WATCHDOG_ON
+ */
+ private boolean isWatchdogEnabled() {
+ return Settings.Secure.getInt(mContentResolver,
+ Settings.Secure.WIFI_WATCHDOG_ON, 1) == 1;
+ }
+
+
+ /**
+ * 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() + ")";
+ }
+
+ /**
+ *
+ */
+ private void resetWatchdogState() {
+ mInitialConnInfo = null;
+ mDisableAPNextFailure = false;
+ mLastWalledGardenCheckTime = null;
+ mNumFullDNSchecks = 0;
+ mBssids.clear();
+ }
+
+ private void popUpBrowser() {
+ Uri uri = Uri.parse("http://www.google.com");
+ Intent intent = new Intent(Intent.ACTION_VIEW, uri);
+ intent.setFlags(Intent.FLAG_ACTIVITY_BROUGHT_TO_FRONT |
+ Intent.FLAG_ACTIVITY_NEW_TASK);
+ mContext.startActivity(intent);
+ }
+
+ private void sendCheckStepMessage(long delay) {
+ sendMessageDelayed(obtainMessage(MESSAGE_CHECK_STEP, mNetEventCounter, 0), delay);
+ }
+
+ class DefaultState extends State {
+ @Override
+ public boolean processMessage(Message msg) {
+ if (VDBG) {
+ Slog.v(WWSM_TAG, "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);
+ Slog.i(WWSM_TAG, "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);
+
+ switch (networkInfo.getState()) {
+ case CONNECTED:
+ // WifiInfo wifiInfo = (WifiInfo)
+ // stateChangeIntent
+ // .getParcelableExtra(WifiManager.EXTRA_WIFI_INFO);
+ // TODO : Replace with above code when API is changed
+ WifiInfo wifiInfo = mWifiManager.getConnectionInfo();
+ if (wifiInfo == null) {
+ Slog.e(WWSM_TAG, "Connected --> WifiInfo object null!");
+ return HANDLED;
+ }
+
+ if (wifiInfo.getSSID() == null || wifiInfo.getBSSID() == null) {
+ Slog.e(WWSM_TAG, "Received wifiInfo object with null elts: "
+ + wifiInfoToStr(wifiInfo));
+ return HANDLED;
+ }
+
+ initConnection(wifiInfo);
+ transitionTo(mDnsCheckingState);
+ mNetEventCounter++;
+ return HANDLED;
+ case DISCONNECTED:
+ case DISCONNECTING:
+ mNetEventCounter++;
+ transitionTo(mNotConnectedState);
+ return HANDLED;
+ }
+ return HANDLED;
+ case EVENT_WIFI_RADIO_STATE_CHANGE:
+ if ((Integer) msg.obj == WifiManager.WIFI_STATE_DISABLING) {
+ Slog.i(WWSM_TAG, "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 (VDBG) {
+ Slog.v(WWSM_TAG, "Connected:: old " + wifiInfoToStr(mInitialConnInfo) +
+ " ==> new " + wifiInfoToStr(wifiInfo));
+ }
+
+ if (mInitialConnInfo == null || !wifiInfo.getSSID().equals(mInitialConnInfo.getSSID())) {
+ resetWatchdogState();
+ } else if (!wifiInfo.getBSSID().equals(mInitialConnInfo.getBSSID())) {
+ mDisableAPNextFailure = false;
+ }
+ mInitialConnInfo = wifiInfo;
+ }
+
+ @Override
+ public void exit() {
+ mContext.unregisterReceiver(mBroadcastReceiver);
+ Slog.i(WWSM_TAG, "WifiWatchdogService disabled");
+ }
+ }
+
+ class NotConnectedState extends State {
+ }
+
+ class ConnectedState extends State {
+ @Override
+ public boolean processMessage(Message msg) {
+ switch (msg.what) {
+ case EVENT_SCAN_RESULTS_AVAILABLE:
+ String curSsid = mInitialConnInfo.getSSID();
+ List<ScanResult> results = mWifiManager.getScanResults();
+ int oldNumBssids = mBssids.size();
+
+ if (results == null) {
+ if (DBG) {
+ Slog.d(WWSM_TAG, "updateBssids: Got null scan results!");
+ }
+ return HANDLED;
+ }
+
+ for (ScanResult result : results) {
+ if (result == null || result.SSID == null) {
+ if (VDBG) {
+ Slog.v(WWSM_TAG, "Received invalid scan result: " + result);
+ }
+ continue;
+ }
+ if (curSsid.equals(result.SSID))
+ mBssids.add(result.BSSID);
+ }
+ return HANDLED;
+ }
+ return NOT_HANDLED;
+ }
+
+ }
+
+ class DnsCheckingState extends State {
+ int dnsCheckTries = 0;
+ int dnsCheckSuccesses = 0;
+ String dnsCheckLogStr = "";
+
+ @Override
+ public void enter() {
+ mNumFullDNSchecks++;
+ dnsCheckSuccesses = 0;
+ dnsCheckTries = 0;
+ if (DBG) {
+ Slog.d(WWSM_TAG, "Starting DNS pings at " + SystemClock.elapsedRealtime());
+ dnsCheckLogStr = String.format("Dns Check %d. Pinging %s on ssid [%s]: ",
+ mNumFullDNSchecks, mDnsPinger.getDns(), mInitialConnInfo.getSSID());
+ }
+
+ sendCheckStepMessage(0);
+ }
+
+ @Override
+ public boolean processMessage(Message msg) {
+ if (msg.what != MESSAGE_CHECK_STEP) {
+ return NOT_HANDLED;
+ }
+ if (msg.arg1 != mNetEventCounter) {
+ Slog.d(WWSM_TAG, "Check step out of sync, ignoring...");
+ return HANDLED;
+ }
+
+ long pingResponseTime = mDnsPinger.pingDns(mDnsPinger.getDns(),
+ DNS_PING_TIMEOUT_MS);
+
+ dnsCheckTries++;
+ if (pingResponseTime >= 0)
+ dnsCheckSuccesses++;
+
+ if (DBG) {
+ if (pingResponseTime >= 0) {
+ dnsCheckLogStr += "|" + pingResponseTime;
+ } else {
+ dnsCheckLogStr += "|x";
+ }
+ }
+
+ if (VDBG) {
+ Slog.v(WWSM_TAG, dnsCheckLogStr);
+ }
+
+ /**
+ * After a full ping count, if we have more responses than this
+ * cutoff, the outcome is success; else it is 'failure'.
+ */
+ double pingResponseCutoff = MIN_DNS_RESPONSE_RATE * NUM_DNS_PINGS;
+ int remainingChecks = NUM_DNS_PINGS - dnsCheckTries;
+
+ /**
+ * Our final success count will be at least this big, so we're
+ * guaranteed to succeed.
+ */
+ if (dnsCheckSuccesses >= pingResponseCutoff) {
+ // DNS CHECKS OK, NOW WALLED GARDEN
+ if (DBG) {
+ Slog.d(WWSM_TAG, dnsCheckLogStr + "| SUCCESS");
+ }
+
+ if (!shouldCheckWalledGarden()) {
+ transitionTo(mOnlineWatchState);
+ return HANDLED;
+ }
+
+ mLastWalledGardenCheckTime = SystemClock.elapsedRealtime();
+ if (isWalledGardenConnection()) {
+ if (DBG)
+ Slog.d(WWSM_TAG,
+ "Walled garden test complete - walled garden detected");
+ transitionTo(mWalledGardenState);
+ } else {
+ if (DBG)
+ Slog.d(WWSM_TAG, "Walled garden test complete - online");
+ transitionTo(mOnlineWatchState);
+ }
+ return HANDLED;
+ }
+
+ /**
+ * Our final count will be at most the current count plus the
+ * remaining pings - we're guaranteed to fail.
+ */
+ if (remainingChecks + dnsCheckSuccesses < pingResponseCutoff) {
+ if (DBG) {
+ Slog.d(WWSM_TAG, dnsCheckLogStr + "| FAILURE");
+ }
+ transitionTo(mDnsCheckFailureState);
+ return HANDLED;
+ }
+
+ // Still in dns check step
+ sendCheckStepMessage(DNS_PING_INTERVAL_MS);
+ return HANDLED;
+ }
+
+ private boolean shouldCheckWalledGarden() {
+ if (!isWalledGardenTestEnabled()) {
+ if (VDBG)
+ Slog.v(WWSM_TAG, "Skipping walled garden check - disabled");
+ return false;
+ }
+ long waitTime = waitTime(MIN_WALLED_GARDEN_INTERVAL_MS,
+ mLastWalledGardenCheckTime);
+ if (waitTime > 0) {
+ if (DBG) {
+ Slog.d(WWSM_TAG, "Skipping walled garden check - wait " +
+ waitTime + " ms.");
+ }
+ return false;
+ }
+ return true;
+ }
+
+ }
+
+ 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;
+
+ @Override
+ public void enter() {
+ lastCheckTime = SystemClock.elapsedRealtime();
+ signalUnstable = false;
+ checkGuard++;
+ unstableSignalChecks = false;
+ triggerSingleDnsCheck();
+ }
+
+ @Override
+ public boolean processMessage(Message msg) {
+ switch (msg.what) {
+ case EVENT_RSSI_CHANGE:
+ if (msg.arg1 != mNetEventCounter) {
+ if (DBG) {
+ Slog.d(WWSM_TAG, "Rssi change message out of sync, ignoring");
+ }
+ return HANDLED;
+ }
+ int newRssi = msg.arg2;
+ signalUnstable = !rssiStrengthAboveCutoff(newRssi);
+ if (VDBG) {
+ Slog.v(WWSM_TAG, "OnlineWatchState:: new rssi " + newRssi + " --> level " +
+ WifiManager.calculateSignalLevel(newRssi, WIFI_SIGNAL_LEVELS));
+ }
+
+ if (signalUnstable && !unstableSignalChecks) {
+ if (VDBG) {
+ Slog.v(WWSM_TAG, "Sending triggered check msg");
+ }
+ triggerSingleDnsCheck();
+ }
+ return HANDLED;
+ case MESSAGE_SINGLE_DNS_CHECK:
+ if (msg.arg1 != checkGuard) {
+ if (VDBG) {
+ Slog.v(WWSM_TAG, "Single check msg out of sync, ignoring.");
+ }
+ return HANDLED;
+ }
+ lastCheckTime = SystemClock.elapsedRealtime();
+ long responseTime = mDnsPinger.pingDns(mDnsPinger.getDns(),
+ DNS_PING_TIMEOUT_MS);
+ if (responseTime >= 0) {
+ if (VDBG) {
+ Slog.v(WWSM_TAG, "Ran a single DNS ping. Response time: "
+ + responseTime);
+ }
+
+ checkGuard++;
+ unstableSignalChecks = false;
+ triggerSingleDnsCheck();
+ } else {
+ if (DBG) {
+ Slog.d(WWSM_TAG, "Single dns ping failure. Starting full checks.");
+ }
+ transitionTo(mDnsCheckingState);
+ }
+ return HANDLED;
+ }
+ return NOT_HANDLED;
+ }
+
+ /**
+ * Times a dns check with an interval based on {@link #curSignalStable}
+ */
+ private void triggerSingleDnsCheck() {
+ long waitInterval;
+ if (signalUnstable) {
+ waitInterval = MIN_LOW_SIGNAL_CHECK_INTERVAL_MS;
+ unstableSignalChecks = true;
+ } else {
+ waitInterval = MIN_SINGLE_DNS_CHECK_INTERVAL_MS;
+ }
+ sendMessageDelayed(obtainMessage(MESSAGE_SINGLE_DNS_CHECK, checkGuard, 0),
+ waitTime(waitInterval, lastCheckTime));
+ }
+ }
+
+ class DnsCheckFailureState extends State {
+ @Override
+ public void enter() {
+ 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 (VDBG) {
+ Slog.v(WWSM_TAG, "Msg out of sync, ignoring...");
+ }
+ return HANDLED;
+ }
+
+ if (mDisableAPNextFailure || mNumFullDNSchecks >= MAX_CHECKS_PER_SSID) {
+ // TODO : Unban networks if they had low signal ?
+ Slog.i(WWSM_TAG, "Disabling current SSID " + wifiInfoToStr(mInitialConnInfo)
+ + ". " +
+ "numChecks " + mNumFullDNSchecks + ", numAPs " + mBssids.size());
+ mWifiManager.disableNetwork(mInitialConnInfo.getNetworkId());
+ transitionTo(mNotConnectedState);
+ } else {
+ Slog.i(WWSM_TAG, "Blacklisting current BSSID. " + wifiInfoToStr(mInitialConnInfo) +
+ "numChecks " + mNumFullDNSchecks + ", numAPs " + mBssids.size());
+
+ mWifiManager.addToBlacklist(mInitialConnInfo.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 (VDBG) {
+ Slog.v(WWSM_TAG, "WalledGardenState::Msg out of sync, ignoring...");
+ }
+ return HANDLED;
+ }
+ popUpBrowser();
+ transitionTo(mOnlineWatchState);
+ return HANDLED;
+ }
+ }
+
+ class BlacklistedApState extends State {
+ @Override
+ public void enter() {
+ mDisableAPNextFailure = true;
+ sendMessageDelayed(obtainMessage(MESSAGE_NETWORK_FOLLOWUP, mNetEventCounter, 0),
+ BLACKLIST_FOLLOWUP_INTERVAL_MS);
+ }
+
+ @Override
+ public boolean processMessage(Message msg) {
+ if (msg.what != MESSAGE_NETWORK_FOLLOWUP) {
+ return NOT_HANDLED;
+ }
+
+ if (msg.arg1 != mNetEventCounter) {
+ if (VDBG) {
+ Slog.v(WWSM_TAG, "BlacklistedApState::Msg out of sync, ignoring...");
+ }
+ return HANDLED;
+ }
+
+ transitionTo(mDnsCheckingState);
+ return HANDLED;
+ }
+ }
+}