| /* |
| * Copyright (C) 2014 The Android Open Source Project |
| * |
| * Licensed under the Apache License, Version 2.0 (the "License"); |
| * you may not use this file except in compliance with the License. |
| * You may obtain a copy of the License at |
| * |
| * http://www.apache.org/licenses/LICENSE-2.0 |
| * |
| * Unless required by applicable law or agreed to in writing, software |
| * distributed under the License is distributed on an "AS IS" BASIS, |
| * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. |
| * See the License for the specific language governing permissions and |
| * limitations under the License. |
| */ |
| |
| package com.android.server.connectivity; |
| |
| import static android.net.CaptivePortal.APP_RETURN_DISMISSED; |
| import static android.net.CaptivePortal.APP_RETURN_UNWANTED; |
| import static android.net.CaptivePortal.APP_RETURN_WANTED_AS_IS; |
| |
| import android.app.AlarmManager; |
| import android.app.PendingIntent; |
| import android.content.BroadcastReceiver; |
| import android.content.Context; |
| import android.content.Intent; |
| import android.content.IntentFilter; |
| import android.net.CaptivePortal; |
| import android.net.ConnectivityManager; |
| import android.net.ICaptivePortal; |
| import android.net.NetworkRequest; |
| import android.net.ProxyInfo; |
| import android.net.TrafficStats; |
| import android.net.Uri; |
| import android.net.metrics.IpConnectivityLog; |
| import android.net.metrics.NetworkEvent; |
| import android.net.metrics.ValidationProbeEvent; |
| import android.net.util.Stopwatch; |
| import android.net.wifi.WifiInfo; |
| import android.net.wifi.WifiManager; |
| import android.os.Handler; |
| import android.os.Message; |
| import android.os.SystemClock; |
| import android.os.UserHandle; |
| import android.provider.Settings; |
| import android.telephony.CellIdentityCdma; |
| import android.telephony.CellIdentityGsm; |
| import android.telephony.CellIdentityLte; |
| import android.telephony.CellIdentityWcdma; |
| import android.telephony.CellInfo; |
| import android.telephony.CellInfoCdma; |
| import android.telephony.CellInfoGsm; |
| import android.telephony.CellInfoLte; |
| import android.telephony.CellInfoWcdma; |
| import android.telephony.TelephonyManager; |
| import android.text.TextUtils; |
| import android.util.LocalLog; |
| import android.util.LocalLog.ReadOnlyLocalLog; |
| import android.util.Log; |
| |
| import com.android.internal.annotations.VisibleForTesting; |
| import com.android.internal.util.Protocol; |
| import com.android.internal.util.State; |
| import com.android.internal.util.StateMachine; |
| |
| import java.io.IOException; |
| import java.net.HttpURLConnection; |
| import java.net.InetAddress; |
| import java.net.MalformedURLException; |
| import java.net.URL; |
| import java.net.UnknownHostException; |
| import java.util.List; |
| import java.util.Random; |
| import java.util.concurrent.CountDownLatch; |
| import java.util.concurrent.TimeUnit; |
| |
| /** |
| * {@hide} |
| */ |
| public class NetworkMonitor extends StateMachine { |
| private static final String TAG = NetworkMonitor.class.getSimpleName(); |
| private static final boolean DBG = true; |
| private static final boolean VDBG = false; |
| |
| // Default configuration values for captive portal detection probes. |
| // TODO: append a random length parameter to the default HTTPS url. |
| // TODO: randomize browser version ids in the default User-Agent String. |
| private static final String DEFAULT_HTTPS_URL = "https://www.google.com/generate_204"; |
| private static final String DEFAULT_HTTP_URL = |
| "http://connectivitycheck.gstatic.com/generate_204"; |
| private static final String DEFAULT_FALLBACK_URL = "http://www.google.com/gen_204"; |
| private static final String DEFAULT_USER_AGENT = "Mozilla/5.0 (X11; Linux x86_64) " |
| + "AppleWebKit/537.36 (KHTML, like Gecko) " |
| + "Chrome/52.0.2743.82 Safari/537.36"; |
| |
| private static final int SOCKET_TIMEOUT_MS = 10000; |
| private static final int PROBE_TIMEOUT_MS = 3000; |
| |
| static enum EvaluationResult { |
| VALIDATED(true), |
| CAPTIVE_PORTAL(false); |
| final boolean isValidated; |
| EvaluationResult(boolean isValidated) { |
| this.isValidated = isValidated; |
| } |
| } |
| |
| static enum ValidationStage { |
| FIRST_VALIDATION(true), |
| REVALIDATION(false); |
| final boolean isFirstValidation; |
| ValidationStage(boolean isFirstValidation) { |
| this.isFirstValidation = isFirstValidation; |
| } |
| } |
| |
| public static final String ACTION_NETWORK_CONDITIONS_MEASURED = |
| "android.net.conn.NETWORK_CONDITIONS_MEASURED"; |
| public static final String EXTRA_CONNECTIVITY_TYPE = "extra_connectivity_type"; |
| public static final String EXTRA_NETWORK_TYPE = "extra_network_type"; |
| public static final String EXTRA_RESPONSE_RECEIVED = "extra_response_received"; |
| public static final String EXTRA_IS_CAPTIVE_PORTAL = "extra_is_captive_portal"; |
| public static final String EXTRA_CELL_ID = "extra_cellid"; |
| public static final String EXTRA_SSID = "extra_ssid"; |
| public static final String EXTRA_BSSID = "extra_bssid"; |
| /** real time since boot */ |
| public static final String EXTRA_REQUEST_TIMESTAMP_MS = "extra_request_timestamp_ms"; |
| public static final String EXTRA_RESPONSE_TIMESTAMP_MS = "extra_response_timestamp_ms"; |
| |
| private static final String PERMISSION_ACCESS_NETWORK_CONDITIONS = |
| "android.permission.ACCESS_NETWORK_CONDITIONS"; |
| |
| // After a network has been tested this result can be sent with EVENT_NETWORK_TESTED. |
| // The network should be used as a default internet connection. It was found to be: |
| // 1. a functioning network providing internet access, or |
| // 2. a captive portal and the user decided to use it as is. |
| public static final int NETWORK_TEST_RESULT_VALID = 0; |
| // After a network has been tested this result can be sent with EVENT_NETWORK_TESTED. |
| // The network should not be used as a default internet connection. It was found to be: |
| // 1. a captive portal and the user is prompted to sign-in, or |
| // 2. a captive portal and the user did not want to use it, or |
| // 3. a broken network (e.g. DNS failed, connect failed, HTTP request failed). |
| public static final int NETWORK_TEST_RESULT_INVALID = 1; |
| |
| private static final int BASE = Protocol.BASE_NETWORK_MONITOR; |
| |
| /** |
| * Inform NetworkMonitor that their network is connected. |
| * Initiates Network Validation. |
| */ |
| public static final int CMD_NETWORK_CONNECTED = BASE + 1; |
| |
| /** |
| * Inform ConnectivityService that the network has been tested. |
| * obj = String representing URL that Internet probe was redirect to, if it was redirected. |
| * arg1 = One of the NETWORK_TESTED_RESULT_* constants. |
| * arg2 = NetID. |
| */ |
| public static final int EVENT_NETWORK_TESTED = BASE + 2; |
| |
| /** |
| * Message to self indicating it's time to evaluate a network's connectivity. |
| * arg1 = Token to ignore old messages. |
| */ |
| private static final int CMD_REEVALUATE = BASE + 6; |
| |
| /** |
| * Inform NetworkMonitor that the network has disconnected. |
| */ |
| public static final int CMD_NETWORK_DISCONNECTED = BASE + 7; |
| |
| /** |
| * Force evaluation even if it has succeeded in the past. |
| * arg1 = UID responsible for requesting this reeval. Will be billed for data. |
| */ |
| public static final int CMD_FORCE_REEVALUATION = BASE + 8; |
| |
| /** |
| * Message to self indicating captive portal app finished. |
| * arg1 = one of: APP_RETURN_DISMISSED, |
| * APP_RETURN_UNWANTED, |
| * APP_RETURN_WANTED_AS_IS |
| * obj = mCaptivePortalLoggedInResponseToken as String |
| */ |
| private static final int CMD_CAPTIVE_PORTAL_APP_FINISHED = BASE + 9; |
| |
| /** |
| * Request ConnectivityService display provisioning notification. |
| * arg1 = Whether to make the notification visible. |
| * arg2 = NetID. |
| * obj = Intent to be launched when notification selected by user, null if !arg1. |
| */ |
| public static final int EVENT_PROVISIONING_NOTIFICATION = BASE + 10; |
| |
| /** |
| * Message to self indicating sign-in app should be launched. |
| * Sent by mLaunchCaptivePortalAppBroadcastReceiver when the |
| * user touches the sign in notification. |
| */ |
| private static final int CMD_LAUNCH_CAPTIVE_PORTAL_APP = BASE + 11; |
| |
| /** |
| * Retest network to see if captive portal is still in place. |
| * arg1 = UID responsible for requesting this reeval. Will be billed for data. |
| * 0 indicates self-initiated, so nobody to blame. |
| */ |
| private static final int CMD_CAPTIVE_PORTAL_RECHECK = BASE + 12; |
| |
| // Start mReevaluateDelayMs at this value and double. |
| private static final int INITIAL_REEVALUATE_DELAY_MS = 1000; |
| private static final int MAX_REEVALUATE_DELAY_MS = 10*60*1000; |
| // Before network has been evaluated this many times, ignore repeated reevaluate requests. |
| private static final int IGNORE_REEVALUATE_ATTEMPTS = 5; |
| private int mReevaluateToken = 0; |
| private static final int INVALID_UID = -1; |
| private int mUidResponsibleForReeval = INVALID_UID; |
| // Stop blaming UID that requested re-evaluation after this many attempts. |
| private static final int BLAME_FOR_EVALUATION_ATTEMPTS = 5; |
| // Delay between reevaluations once a captive portal has been found. |
| private static final int CAPTIVE_PORTAL_REEVALUATE_DELAY_MS = 10*60*1000; |
| |
| private final Context mContext; |
| private final Handler mConnectivityServiceHandler; |
| private final NetworkAgentInfo mNetworkAgentInfo; |
| private final int mNetId; |
| private final TelephonyManager mTelephonyManager; |
| private final WifiManager mWifiManager; |
| private final AlarmManager mAlarmManager; |
| private final NetworkRequest mDefaultRequest; |
| private final IpConnectivityLog mMetricsLog; |
| |
| @VisibleForTesting |
| protected boolean mIsCaptivePortalCheckEnabled; |
| |
| private boolean mUseHttps; |
| // The total number of captive portal detection attempts for this NetworkMonitor instance. |
| private int mValidations = 0; |
| |
| // Set if the user explicitly selected "Do not use this network" in captive portal sign-in app. |
| private boolean mUserDoesNotWant = false; |
| // Avoids surfacing "Sign in to network" notification. |
| private boolean mDontDisplaySigninNotification = false; |
| |
| public boolean systemReady = false; |
| |
| private final State mDefaultState = new DefaultState(); |
| private final State mValidatedState = new ValidatedState(); |
| private final State mMaybeNotifyState = new MaybeNotifyState(); |
| private final State mEvaluatingState = new EvaluatingState(); |
| private final State mCaptivePortalState = new CaptivePortalState(); |
| |
| private CustomIntentReceiver mLaunchCaptivePortalAppBroadcastReceiver = null; |
| |
| private final LocalLog validationLogs = new LocalLog(20); // 20 lines |
| |
| private final Stopwatch mEvaluationTimer = new Stopwatch(); |
| |
| // This variable is set before transitioning to the mCaptivePortalState. |
| private CaptivePortalProbeResult mLastPortalProbeResult = CaptivePortalProbeResult.FAILED; |
| |
| public NetworkMonitor(Context context, Handler handler, NetworkAgentInfo networkAgentInfo, |
| NetworkRequest defaultRequest) { |
| this(context, handler, networkAgentInfo, defaultRequest, new IpConnectivityLog()); |
| } |
| |
| @VisibleForTesting |
| protected NetworkMonitor(Context context, Handler handler, NetworkAgentInfo networkAgentInfo, |
| NetworkRequest defaultRequest, IpConnectivityLog logger) { |
| // Add suffix indicating which NetworkMonitor we're talking about. |
| super(TAG + networkAgentInfo.name()); |
| |
| mContext = context; |
| mMetricsLog = logger; |
| mConnectivityServiceHandler = handler; |
| mNetworkAgentInfo = networkAgentInfo; |
| mNetId = mNetworkAgentInfo.network.netId; |
| mTelephonyManager = (TelephonyManager) context.getSystemService(Context.TELEPHONY_SERVICE); |
| mWifiManager = (WifiManager) context.getSystemService(Context.WIFI_SERVICE); |
| mAlarmManager = (AlarmManager) context.getSystemService(Context.ALARM_SERVICE); |
| mDefaultRequest = defaultRequest; |
| |
| addState(mDefaultState); |
| addState(mValidatedState, mDefaultState); |
| addState(mMaybeNotifyState, mDefaultState); |
| addState(mEvaluatingState, mMaybeNotifyState); |
| addState(mCaptivePortalState, mMaybeNotifyState); |
| setInitialState(mDefaultState); |
| |
| mIsCaptivePortalCheckEnabled = Settings.Global.getInt(mContext.getContentResolver(), |
| Settings.Global.CAPTIVE_PORTAL_MODE, Settings.Global.CAPTIVE_PORTAL_MODE_PROMPT) |
| != Settings.Global.CAPTIVE_PORTAL_MODE_IGNORE; |
| mUseHttps = Settings.Global.getInt(mContext.getContentResolver(), |
| Settings.Global.CAPTIVE_PORTAL_USE_HTTPS, 1) == 1; |
| |
| start(); |
| } |
| |
| @Override |
| protected void log(String s) { |
| if (DBG) Log.d(TAG + "/" + mNetworkAgentInfo.name(), s); |
| } |
| |
| private void validationLog(String s) { |
| if (DBG) log(s); |
| validationLogs.log(s); |
| } |
| |
| public ReadOnlyLocalLog getValidationLogs() { |
| return validationLogs.readOnlyLocalLog(); |
| } |
| |
| private ValidationStage validationStage() { |
| return 0 == mValidations ? ValidationStage.FIRST_VALIDATION : ValidationStage.REVALIDATION; |
| } |
| |
| // DefaultState is the parent of all States. It exists only to handle CMD_* messages but |
| // does not entail any real state (hence no enter() or exit() routines). |
| private class DefaultState extends State { |
| @Override |
| public boolean processMessage(Message message) { |
| switch (message.what) { |
| case CMD_NETWORK_CONNECTED: |
| logNetworkEvent(NetworkEvent.NETWORK_CONNECTED); |
| transitionTo(mEvaluatingState); |
| return HANDLED; |
| case CMD_NETWORK_DISCONNECTED: |
| logNetworkEvent(NetworkEvent.NETWORK_DISCONNECTED); |
| if (mLaunchCaptivePortalAppBroadcastReceiver != null) { |
| mContext.unregisterReceiver(mLaunchCaptivePortalAppBroadcastReceiver); |
| mLaunchCaptivePortalAppBroadcastReceiver = null; |
| } |
| quit(); |
| return HANDLED; |
| case CMD_FORCE_REEVALUATION: |
| case CMD_CAPTIVE_PORTAL_RECHECK: |
| log("Forcing reevaluation for UID " + message.arg1); |
| mUidResponsibleForReeval = message.arg1; |
| transitionTo(mEvaluatingState); |
| return HANDLED; |
| case CMD_CAPTIVE_PORTAL_APP_FINISHED: |
| log("CaptivePortal App responded with " + message.arg1); |
| |
| // If the user has seen and acted on a captive portal notification, and the |
| // captive portal app is now closed, disable HTTPS probes. This avoids the |
| // following pathological situation: |
| // |
| // 1. HTTP probe returns a captive portal, HTTPS probe fails or times out. |
| // 2. User opens the app and logs into the captive portal. |
| // 3. HTTP starts working, but HTTPS still doesn't work for some other reason - |
| // perhaps due to the network blocking HTTPS? |
| // |
| // In this case, we'll fail to validate the network even after the app is |
| // dismissed. There is now no way to use this network, because the app is now |
| // gone, so the user cannot select "Use this network as is". |
| mUseHttps = false; |
| |
| switch (message.arg1) { |
| case APP_RETURN_DISMISSED: |
| sendMessage(CMD_FORCE_REEVALUATION, 0 /* no UID */, 0); |
| break; |
| case APP_RETURN_WANTED_AS_IS: |
| mDontDisplaySigninNotification = true; |
| // TODO: Distinguish this from a network that actually validates. |
| // Displaying the "!" on the system UI icon may still be a good idea. |
| transitionTo(mValidatedState); |
| break; |
| case APP_RETURN_UNWANTED: |
| mDontDisplaySigninNotification = true; |
| mUserDoesNotWant = true; |
| mConnectivityServiceHandler.sendMessage(obtainMessage( |
| EVENT_NETWORK_TESTED, NETWORK_TEST_RESULT_INVALID, |
| mNetId, null)); |
| // TODO: Should teardown network. |
| mUidResponsibleForReeval = 0; |
| transitionTo(mEvaluatingState); |
| break; |
| } |
| return HANDLED; |
| default: |
| return HANDLED; |
| } |
| } |
| } |
| |
| // Being in the ValidatedState State indicates a Network is: |
| // - Successfully validated, or |
| // - Wanted "as is" by the user, or |
| // - Does not satisfy the default NetworkRequest and so validation has been skipped. |
| private class ValidatedState extends State { |
| @Override |
| public void enter() { |
| maybeLogEvaluationResult( |
| networkEventType(validationStage(), EvaluationResult.VALIDATED)); |
| mConnectivityServiceHandler.sendMessage(obtainMessage(EVENT_NETWORK_TESTED, |
| NETWORK_TEST_RESULT_VALID, mNetworkAgentInfo.network.netId, null)); |
| mValidations++; |
| } |
| |
| @Override |
| public boolean processMessage(Message message) { |
| switch (message.what) { |
| case CMD_NETWORK_CONNECTED: |
| transitionTo(mValidatedState); |
| return HANDLED; |
| default: |
| return NOT_HANDLED; |
| } |
| } |
| } |
| |
| // Being in the MaybeNotifyState State indicates the user may have been notified that sign-in |
| // is required. This State takes care to clear the notification upon exit from the State. |
| private class MaybeNotifyState extends State { |
| @Override |
| public boolean processMessage(Message message) { |
| switch (message.what) { |
| case CMD_LAUNCH_CAPTIVE_PORTAL_APP: |
| final Intent intent = new Intent( |
| ConnectivityManager.ACTION_CAPTIVE_PORTAL_SIGN_IN); |
| intent.putExtra(ConnectivityManager.EXTRA_NETWORK, mNetworkAgentInfo.network); |
| intent.putExtra(ConnectivityManager.EXTRA_CAPTIVE_PORTAL, |
| new CaptivePortal(new ICaptivePortal.Stub() { |
| @Override |
| public void appResponse(int response) { |
| if (response == APP_RETURN_WANTED_AS_IS) { |
| mContext.enforceCallingPermission( |
| android.Manifest.permission.CONNECTIVITY_INTERNAL, |
| "CaptivePortal"); |
| } |
| sendMessage(CMD_CAPTIVE_PORTAL_APP_FINISHED, response); |
| } |
| })); |
| intent.putExtra(ConnectivityManager.EXTRA_CAPTIVE_PORTAL_URL, |
| mLastPortalProbeResult.detectUrl); |
| intent.putExtra(ConnectivityManager.EXTRA_CAPTIVE_PORTAL_USER_AGENT, |
| getCaptivePortalUserAgent(mContext)); |
| intent.setFlags( |
| Intent.FLAG_ACTIVITY_BROUGHT_TO_FRONT | Intent.FLAG_ACTIVITY_NEW_TASK); |
| mContext.startActivityAsUser(intent, UserHandle.CURRENT); |
| return HANDLED; |
| default: |
| return NOT_HANDLED; |
| } |
| } |
| |
| @Override |
| public void exit() { |
| Message message = obtainMessage(EVENT_PROVISIONING_NOTIFICATION, 0, |
| mNetworkAgentInfo.network.netId, null); |
| mConnectivityServiceHandler.sendMessage(message); |
| } |
| } |
| |
| /** |
| * Result of calling isCaptivePortal(). |
| * @hide |
| */ |
| @VisibleForTesting |
| public static final class CaptivePortalProbeResult { |
| static final CaptivePortalProbeResult FAILED = new CaptivePortalProbeResult(599); |
| |
| private final int mHttpResponseCode; // HTTP response code returned from Internet probe. |
| final String redirectUrl; // Redirect destination returned from Internet probe. |
| final String detectUrl; // URL where a 204 response code indicates |
| // captive portal has been appeased. |
| |
| public CaptivePortalProbeResult( |
| int httpResponseCode, String redirectUrl, String detectUrl) { |
| mHttpResponseCode = httpResponseCode; |
| this.redirectUrl = redirectUrl; |
| this.detectUrl = detectUrl; |
| } |
| |
| public CaptivePortalProbeResult(int httpResponseCode) { |
| this(httpResponseCode, null, null); |
| } |
| |
| boolean isSuccessful() { return mHttpResponseCode == 204; } |
| boolean isPortal() { |
| return !isSuccessful() && mHttpResponseCode >= 200 && mHttpResponseCode <= 399; |
| } |
| } |
| |
| // Being in the EvaluatingState State indicates the Network is being evaluated for internet |
| // connectivity, or that the user has indicated that this network is unwanted. |
| private class EvaluatingState extends State { |
| private int mReevaluateDelayMs; |
| private int mAttempts; |
| |
| @Override |
| public void enter() { |
| // If we have already started to track time spent in EvaluatingState |
| // don't reset the timer due simply to, say, commands or events that |
| // cause us to exit and re-enter EvaluatingState. |
| if (!mEvaluationTimer.isStarted()) { |
| mEvaluationTimer.start(); |
| } |
| sendMessage(CMD_REEVALUATE, ++mReevaluateToken, 0); |
| if (mUidResponsibleForReeval != INVALID_UID) { |
| TrafficStats.setThreadStatsUid(mUidResponsibleForReeval); |
| mUidResponsibleForReeval = INVALID_UID; |
| } |
| mReevaluateDelayMs = INITIAL_REEVALUATE_DELAY_MS; |
| mAttempts = 0; |
| } |
| |
| @Override |
| public boolean processMessage(Message message) { |
| switch (message.what) { |
| case CMD_REEVALUATE: |
| if (message.arg1 != mReevaluateToken || mUserDoesNotWant) |
| return HANDLED; |
| // Don't bother validating networks that don't satisify the default request. |
| // This includes: |
| // - VPNs which can be considered explicitly desired by the user and the |
| // user's desire trumps whether the network validates. |
| // - Networks that don't provide internet access. It's unclear how to |
| // validate such networks. |
| // - Untrusted networks. It's unsafe to prompt the user to sign-in to |
| // such networks and the user didn't express interest in connecting to |
| // such networks (an app did) so the user may be unhappily surprised when |
| // asked to sign-in to a network they didn't want to connect to in the |
| // first place. Validation could be done to adjust the network scores |
| // however these networks are app-requested and may not be intended for |
| // general usage, in which case general validation may not be an accurate |
| // measure of the network's quality. Only the app knows how to evaluate |
| // the network so don't bother validating here. Furthermore sending HTTP |
| // packets over the network may be undesirable, for example an extremely |
| // expensive metered network, or unwanted leaking of the User Agent string. |
| if (!mDefaultRequest.networkCapabilities.satisfiedByNetworkCapabilities( |
| mNetworkAgentInfo.networkCapabilities)) { |
| validationLog("Network would not satisfy default request, not validating"); |
| transitionTo(mValidatedState); |
| return HANDLED; |
| } |
| mAttempts++; |
| // Note: This call to isCaptivePortal() could take up to a minute. Resolving the |
| // server's IP addresses could hit the DNS timeout, and attempting connections |
| // to each of the server's several IP addresses (currently one IPv4 and one |
| // IPv6) could each take SOCKET_TIMEOUT_MS. During this time this StateMachine |
| // will be unresponsive. isCaptivePortal() could be executed on another Thread |
| // if this is found to cause problems. |
| CaptivePortalProbeResult probeResult = isCaptivePortal(); |
| if (probeResult.isSuccessful()) { |
| transitionTo(mValidatedState); |
| } else if (probeResult.isPortal()) { |
| mConnectivityServiceHandler.sendMessage(obtainMessage(EVENT_NETWORK_TESTED, |
| NETWORK_TEST_RESULT_INVALID, mNetId, probeResult.redirectUrl)); |
| mLastPortalProbeResult = probeResult; |
| transitionTo(mCaptivePortalState); |
| } else { |
| final Message msg = obtainMessage(CMD_REEVALUATE, ++mReevaluateToken, 0); |
| sendMessageDelayed(msg, mReevaluateDelayMs); |
| logNetworkEvent(NetworkEvent.NETWORK_VALIDATION_FAILED); |
| mConnectivityServiceHandler.sendMessage(obtainMessage( |
| EVENT_NETWORK_TESTED, NETWORK_TEST_RESULT_INVALID, mNetId, |
| probeResult.redirectUrl)); |
| if (mAttempts >= BLAME_FOR_EVALUATION_ATTEMPTS) { |
| // Don't continue to blame UID forever. |
| TrafficStats.clearThreadStatsUid(); |
| } |
| mReevaluateDelayMs *= 2; |
| if (mReevaluateDelayMs > MAX_REEVALUATE_DELAY_MS) { |
| mReevaluateDelayMs = MAX_REEVALUATE_DELAY_MS; |
| } |
| } |
| return HANDLED; |
| case CMD_FORCE_REEVALUATION: |
| // Before IGNORE_REEVALUATE_ATTEMPTS attempts are made, |
| // ignore any re-evaluation requests. After, restart the |
| // evaluation process via EvaluatingState#enter. |
| return (mAttempts < IGNORE_REEVALUATE_ATTEMPTS) ? HANDLED : NOT_HANDLED; |
| default: |
| return NOT_HANDLED; |
| } |
| } |
| |
| @Override |
| public void exit() { |
| TrafficStats.clearThreadStatsUid(); |
| } |
| } |
| |
| // BroadcastReceiver that waits for a particular Intent and then posts a message. |
| private class CustomIntentReceiver extends BroadcastReceiver { |
| private final int mToken; |
| private final int mWhat; |
| private final String mAction; |
| CustomIntentReceiver(String action, int token, int what) { |
| mToken = token; |
| mWhat = what; |
| mAction = action + "_" + mNetworkAgentInfo.network.netId + "_" + token; |
| mContext.registerReceiver(this, new IntentFilter(mAction)); |
| } |
| public PendingIntent getPendingIntent() { |
| final Intent intent = new Intent(mAction); |
| intent.setPackage(mContext.getPackageName()); |
| return PendingIntent.getBroadcast(mContext, 0, intent, 0); |
| } |
| @Override |
| public void onReceive(Context context, Intent intent) { |
| if (intent.getAction().equals(mAction)) sendMessage(obtainMessage(mWhat, mToken)); |
| } |
| } |
| |
| // Being in the CaptivePortalState State indicates a captive portal was detected and the user |
| // has been shown a notification to sign-in. |
| private class CaptivePortalState extends State { |
| private static final String ACTION_LAUNCH_CAPTIVE_PORTAL_APP = |
| "android.net.netmon.launchCaptivePortalApp"; |
| |
| @Override |
| public void enter() { |
| maybeLogEvaluationResult( |
| networkEventType(validationStage(), EvaluationResult.CAPTIVE_PORTAL)); |
| // Don't annoy user with sign-in notifications. |
| if (mDontDisplaySigninNotification) return; |
| // Create a CustomIntentReceiver that sends us a |
| // CMD_LAUNCH_CAPTIVE_PORTAL_APP message when the user |
| // touches the notification. |
| if (mLaunchCaptivePortalAppBroadcastReceiver == null) { |
| // Wait for result. |
| mLaunchCaptivePortalAppBroadcastReceiver = new CustomIntentReceiver( |
| ACTION_LAUNCH_CAPTIVE_PORTAL_APP, new Random().nextInt(), |
| CMD_LAUNCH_CAPTIVE_PORTAL_APP); |
| } |
| // Display the sign in notification. |
| Message message = obtainMessage(EVENT_PROVISIONING_NOTIFICATION, 1, |
| mNetworkAgentInfo.network.netId, |
| mLaunchCaptivePortalAppBroadcastReceiver.getPendingIntent()); |
| mConnectivityServiceHandler.sendMessage(message); |
| // Retest for captive portal occasionally. |
| sendMessageDelayed(CMD_CAPTIVE_PORTAL_RECHECK, 0 /* no UID */, |
| CAPTIVE_PORTAL_REEVALUATE_DELAY_MS); |
| mValidations++; |
| } |
| |
| @Override |
| public void exit() { |
| removeMessages(CMD_CAPTIVE_PORTAL_RECHECK); |
| } |
| } |
| |
| private static String getCaptivePortalServerHttpsUrl(Context context) { |
| return getSetting(context, Settings.Global.CAPTIVE_PORTAL_HTTPS_URL, DEFAULT_HTTPS_URL); |
| } |
| |
| public static String getCaptivePortalServerHttpUrl(Context context) { |
| return getSetting(context, Settings.Global.CAPTIVE_PORTAL_HTTP_URL, DEFAULT_HTTP_URL); |
| } |
| |
| private static String getCaptivePortalFallbackUrl(Context context) { |
| return getSetting(context, |
| Settings.Global.CAPTIVE_PORTAL_FALLBACK_URL, DEFAULT_FALLBACK_URL); |
| } |
| |
| private static String getCaptivePortalUserAgent(Context context) { |
| return getSetting(context, Settings.Global.CAPTIVE_PORTAL_USER_AGENT, DEFAULT_USER_AGENT); |
| } |
| |
| private static String getSetting(Context context, String symbol, String defaultValue) { |
| final String value = Settings.Global.getString(context.getContentResolver(), symbol); |
| return value != null ? value : defaultValue; |
| } |
| |
| @VisibleForTesting |
| protected CaptivePortalProbeResult isCaptivePortal() { |
| if (!mIsCaptivePortalCheckEnabled) { |
| validationLog("Validation disabled."); |
| return new CaptivePortalProbeResult(204); |
| } |
| |
| URL pacUrl = null, httpsUrl = null, httpUrl = null, fallbackUrl = null; |
| |
| // On networks with a PAC instead of fetching a URL that should result in a 204 |
| // response, we instead simply fetch the PAC script. This is done for a few reasons: |
| // 1. At present our PAC code does not yet handle multiple PACs on multiple networks |
| // until something like https://android-review.googlesource.com/#/c/115180/ lands. |
| // Network.openConnection() will ignore network-specific PACs and instead fetch |
| // using NO_PROXY. If a PAC is in place, the only fetch we know will succeed with |
| // NO_PROXY is the fetch of the PAC itself. |
| // 2. To proxy the generate_204 fetch through a PAC would require a number of things |
| // happen before the fetch can commence, namely: |
| // a) the PAC script be fetched |
| // b) a PAC script resolver service be fired up and resolve the captive portal |
| // server. |
| // Network validation could be delayed until these prerequisities are satisifed or |
| // could simply be left to race them. Neither is an optimal solution. |
| // 3. PAC scripts are sometimes used to block or restrict Internet access and may in |
| // fact block fetching of the generate_204 URL which would lead to false negative |
| // results for network validation. |
| final ProxyInfo proxyInfo = mNetworkAgentInfo.linkProperties.getHttpProxy(); |
| if (proxyInfo != null && !Uri.EMPTY.equals(proxyInfo.getPacFileUrl())) { |
| pacUrl = makeURL(proxyInfo.getPacFileUrl().toString()); |
| if (pacUrl == null) { |
| return CaptivePortalProbeResult.FAILED; |
| } |
| } |
| |
| if (pacUrl == null) { |
| httpsUrl = makeURL(getCaptivePortalServerHttpsUrl(mContext)); |
| httpUrl = makeURL(getCaptivePortalServerHttpUrl(mContext)); |
| fallbackUrl = makeURL(getCaptivePortalFallbackUrl(mContext)); |
| if (httpUrl == null || httpsUrl == null) { |
| return CaptivePortalProbeResult.FAILED; |
| } |
| } |
| |
| long startTime = SystemClock.elapsedRealtime(); |
| |
| final CaptivePortalProbeResult result; |
| if (pacUrl != null) { |
| result = sendDnsAndHttpProbes(null, pacUrl, ValidationProbeEvent.PROBE_PAC); |
| } else if (mUseHttps) { |
| result = sendParallelHttpProbes(proxyInfo, httpsUrl, httpUrl, fallbackUrl); |
| } else { |
| result = sendDnsAndHttpProbes(proxyInfo, httpUrl, ValidationProbeEvent.PROBE_HTTP); |
| } |
| |
| long endTime = SystemClock.elapsedRealtime(); |
| |
| sendNetworkConditionsBroadcast(true /* response received */, |
| result.isPortal() /* isCaptivePortal */, |
| startTime, endTime); |
| |
| return result; |
| } |
| |
| /** |
| * Do a DNS resolution and URL fetch on a known web server to see if we get the data we expect. |
| * @return a CaptivePortalProbeResult inferred from the HTTP response. |
| */ |
| private CaptivePortalProbeResult sendDnsAndHttpProbes(ProxyInfo proxy, URL url, int probeType) { |
| // Pre-resolve the captive portal server host so we can log it. |
| // Only do this if HttpURLConnection is about to, to avoid any potentially |
| // unnecessary resolution. |
| final String host = (proxy != null) ? proxy.getHost() : url.getHost(); |
| sendDnsProbe(host); |
| return sendHttpProbe(url, probeType); |
| } |
| |
| /** Do a DNS resolution of the given server. */ |
| private void sendDnsProbe(String host) { |
| if (TextUtils.isEmpty(host)) { |
| return; |
| } |
| |
| final String name = ValidationProbeEvent.getProbeName(ValidationProbeEvent.PROBE_DNS); |
| final Stopwatch watch = new Stopwatch().start(); |
| int result; |
| String connectInfo; |
| try { |
| InetAddress[] addresses = mNetworkAgentInfo.network.getAllByName(host); |
| result = ValidationProbeEvent.DNS_SUCCESS; |
| StringBuffer buffer = new StringBuffer(host).append("="); |
| for (InetAddress address : addresses) { |
| buffer.append(address.getHostAddress()); |
| if (address != addresses[addresses.length-1]) buffer.append(","); |
| } |
| connectInfo = buffer.toString(); |
| } catch (UnknownHostException e) { |
| result = ValidationProbeEvent.DNS_FAILURE; |
| connectInfo = host; |
| } |
| final long latency = watch.stop(); |
| String resultString = (ValidationProbeEvent.DNS_SUCCESS == result) ? "OK" : "FAIL"; |
| validationLog(String.format("%s %s %dms, %s", name, resultString, latency, connectInfo)); |
| logValidationProbe(latency, ValidationProbeEvent.PROBE_DNS, result); |
| } |
| |
| /** |
| * Do a URL fetch on a known web server to see if we get the data we expect. |
| * @return a CaptivePortalProbeResult inferred from the HTTP response. |
| */ |
| @VisibleForTesting |
| protected CaptivePortalProbeResult sendHttpProbe(URL url, int probeType) { |
| HttpURLConnection urlConnection = null; |
| int httpResponseCode = 599; |
| String redirectUrl = null; |
| final Stopwatch probeTimer = new Stopwatch().start(); |
| try { |
| urlConnection = (HttpURLConnection) mNetworkAgentInfo.network.openConnection(url); |
| urlConnection.setInstanceFollowRedirects(probeType == ValidationProbeEvent.PROBE_PAC); |
| urlConnection.setConnectTimeout(SOCKET_TIMEOUT_MS); |
| urlConnection.setReadTimeout(SOCKET_TIMEOUT_MS); |
| urlConnection.setUseCaches(false); |
| final String userAgent = getCaptivePortalUserAgent(mContext); |
| if (userAgent != null) { |
| urlConnection.setRequestProperty("User-Agent", userAgent); |
| } |
| |
| // Time how long it takes to get a response to our request |
| long requestTimestamp = SystemClock.elapsedRealtime(); |
| |
| httpResponseCode = urlConnection.getResponseCode(); |
| redirectUrl = urlConnection.getHeaderField("location"); |
| |
| // Time how long it takes to get a response to our request |
| long responseTimestamp = SystemClock.elapsedRealtime(); |
| |
| validationLog(ValidationProbeEvent.getProbeName(probeType) + " " + url + |
| " time=" + (responseTimestamp - requestTimestamp) + "ms" + |
| " ret=" + httpResponseCode + |
| " headers=" + urlConnection.getHeaderFields()); |
| // NOTE: We may want to consider an "HTTP/1.0 204" response to be a captive |
| // portal. The only example of this seen so far was a captive portal. For |
| // the time being go with prior behavior of assuming it's not a captive |
| // portal. If it is considered a captive portal, a different sign-in URL |
| // is needed (i.e. can't browse a 204). This could be the result of an HTTP |
| // proxy server. |
| if (httpResponseCode == 200) { |
| if (probeType == ValidationProbeEvent.PROBE_PAC) { |
| validationLog("PAC fetch 200 response interpreted as 204 response."); |
| httpResponseCode = 204; |
| } else if (urlConnection.getContentLengthLong() == 0) { |
| // Consider 200 response with "Content-length=0" to not be a captive portal. |
| // There's no point in considering this a captive portal as the user cannot |
| // sign-in to an empty page. Probably the result of a broken transparent proxy. |
| // See http://b/9972012. |
| validationLog( |
| "200 response with Content-length=0 interpreted as 204 response."); |
| httpResponseCode = 204; |
| } else if (urlConnection.getContentLengthLong() == -1) { |
| // When no Content-length (default value == -1), attempt to read a byte from the |
| // response. Do not use available() as it is unreliable. See http://b/33498325. |
| if (urlConnection.getInputStream().read() == -1) { |
| validationLog("Empty 200 response interpreted as 204 response."); |
| httpResponseCode = 204; |
| } |
| } |
| } |
| } catch (IOException e) { |
| validationLog("Probably not a portal: exception " + e); |
| if (httpResponseCode == 599) { |
| // TODO: Ping gateway and DNS server and log results. |
| } |
| } finally { |
| if (urlConnection != null) { |
| urlConnection.disconnect(); |
| } |
| } |
| logValidationProbe(probeTimer.stop(), probeType, httpResponseCode); |
| return new CaptivePortalProbeResult(httpResponseCode, redirectUrl, url.toString()); |
| } |
| |
| private CaptivePortalProbeResult sendParallelHttpProbes( |
| ProxyInfo proxy, URL httpsUrl, URL httpUrl, URL fallbackUrl) { |
| // Number of probes to wait for. If a probe completes with a conclusive answer |
| // it shortcuts the latch immediately by forcing the count to 0. |
| final CountDownLatch latch = new CountDownLatch(2); |
| |
| final class ProbeThread extends Thread { |
| private final boolean mIsHttps; |
| private volatile CaptivePortalProbeResult mResult = CaptivePortalProbeResult.FAILED; |
| |
| public ProbeThread(boolean isHttps) { |
| mIsHttps = isHttps; |
| } |
| |
| public CaptivePortalProbeResult result() { |
| return mResult; |
| } |
| |
| @Override |
| public void run() { |
| if (mIsHttps) { |
| mResult = |
| sendDnsAndHttpProbes(proxy, httpsUrl, ValidationProbeEvent.PROBE_HTTPS); |
| } else { |
| mResult = sendDnsAndHttpProbes(proxy, httpUrl, ValidationProbeEvent.PROBE_HTTP); |
| } |
| if ((mIsHttps && mResult.isSuccessful()) || (!mIsHttps && mResult.isPortal())) { |
| // Stop waiting immediately if https succeeds or if http finds a portal. |
| while (latch.getCount() > 0) { |
| latch.countDown(); |
| } |
| } |
| // Signal this probe has completed. |
| latch.countDown(); |
| } |
| } |
| |
| final ProbeThread httpsProbe = new ProbeThread(true); |
| final ProbeThread httpProbe = new ProbeThread(false); |
| |
| try { |
| httpsProbe.start(); |
| httpProbe.start(); |
| latch.await(PROBE_TIMEOUT_MS, TimeUnit.MILLISECONDS); |
| } catch (InterruptedException e) { |
| validationLog("Error: probes wait interrupted!"); |
| return CaptivePortalProbeResult.FAILED; |
| } |
| |
| final CaptivePortalProbeResult httpsResult = httpsProbe.result(); |
| final CaptivePortalProbeResult httpResult = httpProbe.result(); |
| |
| // Look for a conclusive probe result first. |
| if (httpResult.isPortal()) { |
| return httpResult; |
| } |
| // httpsResult.isPortal() is not expected, but check it nonetheless. |
| if (httpsResult.isPortal() || httpsResult.isSuccessful()) { |
| return httpsResult; |
| } |
| // If a fallback url is specified, use a fallback probe to try again portal detection. |
| if (fallbackUrl != null) { |
| CaptivePortalProbeResult result = |
| sendHttpProbe(fallbackUrl, ValidationProbeEvent.PROBE_FALLBACK); |
| if (result.isPortal()) { |
| return result; |
| } |
| } |
| // Otherwise wait until https probe completes and use its result. |
| try { |
| httpsProbe.join(); |
| } catch (InterruptedException e) { |
| validationLog("Error: https probe wait interrupted!"); |
| return CaptivePortalProbeResult.FAILED; |
| } |
| return httpsProbe.result(); |
| } |
| |
| private URL makeURL(String url) { |
| if (url != null) { |
| try { |
| return new URL(url); |
| } catch (MalformedURLException e) { |
| validationLog("Bad URL: " + url); |
| } |
| } |
| return null; |
| } |
| |
| /** |
| * @param responseReceived - whether or not we received a valid HTTP response to our request. |
| * If false, isCaptivePortal and responseTimestampMs are ignored |
| * TODO: This should be moved to the transports. The latency could be passed to the transports |
| * along with the captive portal result. Currently the TYPE_MOBILE broadcasts appear unused so |
| * perhaps this could just be added to the WiFi transport only. |
| */ |
| private void sendNetworkConditionsBroadcast(boolean responseReceived, boolean isCaptivePortal, |
| long requestTimestampMs, long responseTimestampMs) { |
| if (Settings.Global.getInt(mContext.getContentResolver(), |
| Settings.Global.WIFI_SCAN_ALWAYS_AVAILABLE, 0) == 0) { |
| return; |
| } |
| |
| if (systemReady == false) return; |
| |
| Intent latencyBroadcast = new Intent(ACTION_NETWORK_CONDITIONS_MEASURED); |
| switch (mNetworkAgentInfo.networkInfo.getType()) { |
| case ConnectivityManager.TYPE_WIFI: |
| WifiInfo currentWifiInfo = mWifiManager.getConnectionInfo(); |
| if (currentWifiInfo != null) { |
| // NOTE: getSSID()'s behavior changed in API 17; before that, SSIDs were not |
| // surrounded by double quotation marks (thus violating the Javadoc), but this |
| // was changed to match the Javadoc in API 17. Since clients may have started |
| // sanitizing the output of this method since API 17 was released, we should |
| // not change it here as it would become impossible to tell whether the SSID is |
| // simply being surrounded by quotes due to the API, or whether those quotes |
| // are actually part of the SSID. |
| latencyBroadcast.putExtra(EXTRA_SSID, currentWifiInfo.getSSID()); |
| latencyBroadcast.putExtra(EXTRA_BSSID, currentWifiInfo.getBSSID()); |
| } else { |
| if (VDBG) logw("network info is TYPE_WIFI but no ConnectionInfo found"); |
| return; |
| } |
| break; |
| case ConnectivityManager.TYPE_MOBILE: |
| latencyBroadcast.putExtra(EXTRA_NETWORK_TYPE, mTelephonyManager.getNetworkType()); |
| List<CellInfo> info = mTelephonyManager.getAllCellInfo(); |
| if (info == null) return; |
| int numRegisteredCellInfo = 0; |
| for (CellInfo cellInfo : info) { |
| if (cellInfo.isRegistered()) { |
| numRegisteredCellInfo++; |
| if (numRegisteredCellInfo > 1) { |
| if (VDBG) logw("more than one registered CellInfo." + |
| " Can't tell which is active. Bailing."); |
| return; |
| } |
| if (cellInfo instanceof CellInfoCdma) { |
| CellIdentityCdma cellId = ((CellInfoCdma) cellInfo).getCellIdentity(); |
| latencyBroadcast.putExtra(EXTRA_CELL_ID, cellId); |
| } else if (cellInfo instanceof CellInfoGsm) { |
| CellIdentityGsm cellId = ((CellInfoGsm) cellInfo).getCellIdentity(); |
| latencyBroadcast.putExtra(EXTRA_CELL_ID, cellId); |
| } else if (cellInfo instanceof CellInfoLte) { |
| CellIdentityLte cellId = ((CellInfoLte) cellInfo).getCellIdentity(); |
| latencyBroadcast.putExtra(EXTRA_CELL_ID, cellId); |
| } else if (cellInfo instanceof CellInfoWcdma) { |
| CellIdentityWcdma cellId = ((CellInfoWcdma) cellInfo).getCellIdentity(); |
| latencyBroadcast.putExtra(EXTRA_CELL_ID, cellId); |
| } else { |
| if (VDBG) logw("Registered cellinfo is unrecognized"); |
| return; |
| } |
| } |
| } |
| break; |
| default: |
| return; |
| } |
| latencyBroadcast.putExtra(EXTRA_CONNECTIVITY_TYPE, mNetworkAgentInfo.networkInfo.getType()); |
| latencyBroadcast.putExtra(EXTRA_RESPONSE_RECEIVED, responseReceived); |
| latencyBroadcast.putExtra(EXTRA_REQUEST_TIMESTAMP_MS, requestTimestampMs); |
| |
| if (responseReceived) { |
| latencyBroadcast.putExtra(EXTRA_IS_CAPTIVE_PORTAL, isCaptivePortal); |
| latencyBroadcast.putExtra(EXTRA_RESPONSE_TIMESTAMP_MS, responseTimestampMs); |
| } |
| mContext.sendBroadcastAsUser(latencyBroadcast, UserHandle.CURRENT, |
| PERMISSION_ACCESS_NETWORK_CONDITIONS); |
| } |
| |
| private void logNetworkEvent(int evtype) { |
| mMetricsLog.log(new NetworkEvent(mNetId, evtype)); |
| } |
| |
| private int networkEventType(ValidationStage s, EvaluationResult r) { |
| if (s.isFirstValidation) { |
| if (r.isValidated) { |
| return NetworkEvent.NETWORK_FIRST_VALIDATION_SUCCESS; |
| } else { |
| return NetworkEvent.NETWORK_FIRST_VALIDATION_PORTAL_FOUND; |
| } |
| } else { |
| if (r.isValidated) { |
| return NetworkEvent.NETWORK_REVALIDATION_SUCCESS; |
| } else { |
| return NetworkEvent.NETWORK_REVALIDATION_PORTAL_FOUND; |
| } |
| } |
| } |
| |
| private void maybeLogEvaluationResult(int evtype) { |
| if (mEvaluationTimer.isRunning()) { |
| mMetricsLog.log(new NetworkEvent(mNetId, evtype, mEvaluationTimer.stop())); |
| mEvaluationTimer.reset(); |
| } |
| } |
| |
| private void logValidationProbe(long durationMs, int probeType, int probeResult) { |
| probeType = |
| ValidationProbeEvent.makeProbeType(probeType, validationStage().isFirstValidation); |
| mMetricsLog.log(new ValidationProbeEvent(mNetId, durationMs, probeType, probeResult)); |
| } |
| } |
