1 /* 2 * Copyright (C) 2012 The Android Open Source Project 3 * 4 * Licensed under the Apache License, Version 2.0 (the "License"); 5 * you may not use this file except in compliance with the License. 6 * You may obtain a copy of the License at 7 * 8 * http://www.apache.org/licenses/LICENSE-2.0 9 * 10 * Unless required by applicable law or agreed to in writing, software 11 * distributed under the License is distributed on an "AS IS" BASIS, 12 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. 13 * See the License for the specific language governing permissions and 14 * limitations under the License. 15 */ 16 17 package android.net; 18 19 import android.app.Activity; 20 import android.app.Notification; 21 import android.app.NotificationManager; 22 import android.app.PendingIntent; 23 import android.content.BroadcastReceiver; 24 import android.content.Context; 25 import android.content.Intent; 26 import android.content.IntentFilter; 27 import android.content.res.Resources; 28 import android.database.ContentObserver; 29 import android.net.ConnectivityManager; 30 import android.net.IConnectivityManager; 31 import android.os.Handler; 32 import android.os.UserHandle; 33 import android.os.Message; 34 import android.os.RemoteException; 35 import android.provider.Settings; 36 import android.telephony.TelephonyManager; 37 import android.text.TextUtils; 38 39 import com.android.internal.util.State; 40 import com.android.internal.util.StateMachine; 41 42 import java.io.IOException; 43 import java.net.HttpURLConnection; 44 import java.net.InetAddress; 45 import java.net.Inet4Address; 46 import java.net.SocketTimeoutException; 47 import java.net.URL; 48 import java.net.UnknownHostException; 49 50 import com.android.internal.R; 51 52 /** 53 * This class allows captive portal detection on a network. 54 * @hide 55 */ 56 public class CaptivePortalTracker extends StateMachine { 57 private static final boolean DBG = true; 58 private static final String TAG = "CaptivePortalTracker"; 59 60 private static final String DEFAULT_SERVER = "clients3.google.com"; 61 62 private static final int SOCKET_TIMEOUT_MS = 10000; 63 64 private String mServer; 65 private String mUrl; 66 private boolean mIsCaptivePortalCheckEnabled = false; 67 private IConnectivityManager mConnService; 68 private TelephonyManager mTelephonyManager; 69 private Context mContext; 70 private NetworkInfo mNetworkInfo; 71 72 private static final int CMD_DETECT_PORTAL = 0; 73 private static final int CMD_CONNECTIVITY_CHANGE = 1; 74 private static final int CMD_DELAYED_CAPTIVE_CHECK = 2; 75 76 /* This delay happens every time before we do a captive check on a network */ 77 private static final int DELAYED_CHECK_INTERVAL_MS = 10000; 78 private int mDelayedCheckToken = 0; 79 80 private State mDefaultState = new DefaultState(); 81 private State mNoActiveNetworkState = new NoActiveNetworkState(); 82 private State mActiveNetworkState = new ActiveNetworkState(); 83 private State mDelayedCaptiveCheckState = new DelayedCaptiveCheckState(); 84 85 private static final String SETUP_WIZARD_PACKAGE = "com.google.android.setupwizard"; 86 private boolean mDeviceProvisioned = false; 87 private ProvisioningObserver mProvisioningObserver; 88 89 private CaptivePortalTracker(Context context, IConnectivityManager cs) { 90 super(TAG); 91 92 mContext = context; 93 mConnService = cs; 94 mTelephonyManager = (TelephonyManager) context.getSystemService(Context.TELEPHONY_SERVICE); 95 mProvisioningObserver = new ProvisioningObserver(); 96 97 IntentFilter filter = new IntentFilter(); 98 filter.addAction(ConnectivityManager.CONNECTIVITY_ACTION); 99 filter.addAction(ConnectivityManager.CONNECTIVITY_ACTION_IMMEDIATE); 100 mContext.registerReceiver(mReceiver, filter); 101 102 mServer = Settings.Global.getString(mContext.getContentResolver(), 103 Settings.Global.CAPTIVE_PORTAL_SERVER); 104 if (mServer == null) mServer = DEFAULT_SERVER; 105 106 mIsCaptivePortalCheckEnabled = Settings.Global.getInt(mContext.getContentResolver(), 107 Settings.Global.CAPTIVE_PORTAL_DETECTION_ENABLED, 1) == 1; 108 109 addState(mDefaultState); 110 addState(mNoActiveNetworkState, mDefaultState); 111 addState(mActiveNetworkState, mDefaultState); 112 addState(mDelayedCaptiveCheckState, mActiveNetworkState); 113 setInitialState(mNoActiveNetworkState); 114 } 115 116 private class ProvisioningObserver extends ContentObserver { 117 ProvisioningObserver() { 118 super(new Handler()); 119 mContext.getContentResolver().registerContentObserver(Settings.Global.getUriFor( 120 Settings.Global.DEVICE_PROVISIONED), false, this); 121 onChange(false); // load initial value 122 } 123 124 @Override 125 public void onChange(boolean selfChange) { 126 mDeviceProvisioned = Settings.Global.getInt(mContext.getContentResolver(), 127 Settings.Global.DEVICE_PROVISIONED, 0) != 0; 128 } 129 } 130 131 private final BroadcastReceiver mReceiver = new BroadcastReceiver() { 132 @Override 133 public void onReceive(Context context, Intent intent) { 134 String action = intent.getAction(); 135 // Normally, we respond to CONNECTIVITY_ACTION, allowing time for the change in 136 // connectivity to stabilize, but if the device is not yet provisioned, respond 137 // immediately to speed up transit through the setup wizard. 138 if ((mDeviceProvisioned && action.equals(ConnectivityManager.CONNECTIVITY_ACTION)) 139 || (!mDeviceProvisioned 140 && action.equals(ConnectivityManager.CONNECTIVITY_ACTION_IMMEDIATE))) { 141 NetworkInfo info = intent.getParcelableExtra( 142 ConnectivityManager.EXTRA_NETWORK_INFO); 143 sendMessage(obtainMessage(CMD_CONNECTIVITY_CHANGE, info)); 144 } 145 } 146 }; 147 148 public static CaptivePortalTracker makeCaptivePortalTracker(Context context, 149 IConnectivityManager cs) { 150 CaptivePortalTracker captivePortal = new CaptivePortalTracker(context, cs); 151 captivePortal.start(); 152 return captivePortal; 153 } 154 155 public void detectCaptivePortal(NetworkInfo info) { 156 sendMessage(obtainMessage(CMD_DETECT_PORTAL, info)); 157 } 158 159 private class DefaultState extends State { 160 @Override 161 public void enter() { 162 setNotificationOff(); 163 } 164 165 @Override 166 public boolean processMessage(Message message) { 167 if (DBG) log(getName() + message.toString()); 168 switch (message.what) { 169 case CMD_DETECT_PORTAL: 170 NetworkInfo info = (NetworkInfo) message.obj; 171 // Checking on a secondary connection is not supported 172 // yet 173 notifyPortalCheckComplete(info); 174 break; 175 case CMD_CONNECTIVITY_CHANGE: 176 case CMD_DELAYED_CAPTIVE_CHECK: 177 break; 178 default: 179 loge("Ignoring " + message); 180 break; 181 } 182 return HANDLED; 183 } 184 } 185 186 private class NoActiveNetworkState extends State { 187 @Override 188 public void enter() { 189 mNetworkInfo = null; 190 } 191 192 @Override 193 public boolean processMessage(Message message) { 194 if (DBG) log(getName() + message.toString()); 195 InetAddress server; 196 NetworkInfo info; 197 switch (message.what) { 198 case CMD_CONNECTIVITY_CHANGE: 199 info = (NetworkInfo) message.obj; 200 if (info.getType() == ConnectivityManager.TYPE_WIFI) { 201 if (info.isConnected() && isActiveNetwork(info)) { 202 mNetworkInfo = info; 203 transitionTo(mDelayedCaptiveCheckState); 204 } 205 } else { 206 log(getName() + " not a wifi connectivity change, ignore"); 207 } 208 break; 209 default: 210 return NOT_HANDLED; 211 } 212 return HANDLED; 213 } 214 } 215 216 private class ActiveNetworkState extends State { 217 @Override 218 public void enter() { 219 setNotificationOff(); 220 } 221 222 @Override 223 public boolean processMessage(Message message) { 224 NetworkInfo info; 225 switch (message.what) { 226 case CMD_CONNECTIVITY_CHANGE: 227 info = (NetworkInfo) message.obj; 228 if (!info.isConnected() 229 && info.getType() == mNetworkInfo.getType()) { 230 if (DBG) log("Disconnected from active network " + info); 231 transitionTo(mNoActiveNetworkState); 232 } else if (info.getType() != mNetworkInfo.getType() && 233 info.isConnected() && 234 isActiveNetwork(info)) { 235 if (DBG) log("Active network switched " + info); 236 deferMessage(message); 237 transitionTo(mNoActiveNetworkState); 238 } 239 break; 240 default: 241 return NOT_HANDLED; 242 } 243 return HANDLED; 244 } 245 } 246 247 248 249 private class DelayedCaptiveCheckState extends State { 250 @Override 251 public void enter() { 252 Message message = obtainMessage(CMD_DELAYED_CAPTIVE_CHECK, ++mDelayedCheckToken, 0); 253 if (mDeviceProvisioned) { 254 sendMessageDelayed(message, DELAYED_CHECK_INTERVAL_MS); 255 } else { 256 sendMessage(message); 257 } 258 } 259 260 @Override 261 public boolean processMessage(Message message) { 262 if (DBG) log(getName() + message.toString()); 263 switch (message.what) { 264 case CMD_DELAYED_CAPTIVE_CHECK: 265 if (message.arg1 == mDelayedCheckToken) { 266 InetAddress server = lookupHost(mServer); 267 boolean captive = server != null && isCaptivePortal(server); 268 if (captive) { 269 if (DBG) log("Captive network " + mNetworkInfo); 270 } else { 271 if (DBG) log("Not captive network " + mNetworkInfo); 272 } 273 notifyPortalCheckCompleted(mNetworkInfo, captive); 274 if (mDeviceProvisioned) { 275 if (captive) { 276 // Setup Wizard will assist the user in connecting to a captive 277 // portal, so make the notification visible unless during setup 278 try { 279 mConnService.setProvisioningNotificationVisible(true, 280 mNetworkInfo.getType(), mNetworkInfo.getExtraInfo(), mUrl); 281 } catch(RemoteException e) { 282 e.printStackTrace(); 283 } 284 } 285 } else { 286 Intent intent = new Intent( 287 ConnectivityManager.ACTION_CAPTIVE_PORTAL_TEST_COMPLETED); 288 intent.putExtra(ConnectivityManager.EXTRA_IS_CAPTIVE_PORTAL, captive); 289 intent.setPackage(SETUP_WIZARD_PACKAGE); 290 mContext.sendBroadcast(intent); 291 } 292 293 transitionTo(mActiveNetworkState); 294 } 295 break; 296 default: 297 return NOT_HANDLED; 298 } 299 return HANDLED; 300 } 301 } 302 303 private void notifyPortalCheckComplete(NetworkInfo info) { 304 if (info == null) { 305 loge("notifyPortalCheckComplete on null"); 306 return; 307 } 308 try { 309 if (DBG) log("notifyPortalCheckComplete: ni=" + info); 310 mConnService.captivePortalCheckComplete(info); 311 } catch(RemoteException e) { 312 e.printStackTrace(); 313 } 314 } 315 316 private void notifyPortalCheckCompleted(NetworkInfo info, boolean isCaptivePortal) { 317 if (info == null) { 318 loge("notifyPortalCheckComplete on null"); 319 return; 320 } 321 try { 322 if (DBG) log("notifyPortalCheckCompleted: captive=" + isCaptivePortal + " ni=" + info); 323 mConnService.captivePortalCheckCompleted(info, isCaptivePortal); 324 } catch(RemoteException e) { 325 e.printStackTrace(); 326 } 327 } 328 329 private boolean isActiveNetwork(NetworkInfo info) { 330 try { 331 NetworkInfo active = mConnService.getActiveNetworkInfo(); 332 if (active != null && active.getType() == info.getType()) { 333 return true; 334 } 335 } catch (RemoteException e) { 336 e.printStackTrace(); 337 } 338 return false; 339 } 340 341 private void setNotificationOff() { 342 try { 343 mConnService.setProvisioningNotificationVisible(false, ConnectivityManager.TYPE_NONE, 344 null, null); 345 } catch (RemoteException e) { 346 log("setNotificationOff: " + e); 347 } 348 } 349 350 /** 351 * Do a URL fetch on a known server to see if we get the data we expect 352 */ 353 private boolean isCaptivePortal(InetAddress server) { 354 HttpURLConnection urlConnection = null; 355 if (!mIsCaptivePortalCheckEnabled) return false; 356 357 mUrl = "http://" + server.getHostAddress() + "/generate_204"; 358 if (DBG) log("Checking " + mUrl); 359 try { 360 URL url = new URL(mUrl); 361 urlConnection = (HttpURLConnection) url.openConnection(); 362 urlConnection.setInstanceFollowRedirects(false); 363 urlConnection.setConnectTimeout(SOCKET_TIMEOUT_MS); 364 urlConnection.setReadTimeout(SOCKET_TIMEOUT_MS); 365 urlConnection.setUseCaches(false); 366 urlConnection.getInputStream(); 367 // we got a valid response, but not from the real google 368 return urlConnection.getResponseCode() != 204; 369 } catch (IOException e) { 370 if (DBG) log("Probably not a portal: exception " + e); 371 return false; 372 } finally { 373 if (urlConnection != null) { 374 urlConnection.disconnect(); 375 } 376 } 377 } 378 379 private InetAddress lookupHost(String hostname) { 380 InetAddress inetAddress[]; 381 try { 382 inetAddress = InetAddress.getAllByName(hostname); 383 } catch (UnknownHostException e) { 384 return null; 385 } 386 387 for (InetAddress a : inetAddress) { 388 if (a instanceof Inet4Address) return a; 389 } 390 return null; 391 } 392 } 393