1 files changed, 413 insertions, 0 deletions
diff --git a/mobile/android/geckoview/src/main/java/org/mozilla/gecko/GeckoNetworkManager.java b/mobile/android/geckoview/src/main/java/org/mozilla/gecko/GeckoNetworkManager.java
new file mode 100644
index 0000000000..02ed848f6b
--- /dev/null
+++ b/mobile/android/geckoview/src/main/java/org/mozilla/gecko/GeckoNetworkManager.java
@@ -0,0 +1,413 @@
+/* -*- Mode: Java; c-basic-offset: 4; tab-width: 4; indent-tabs-mode: nil; -*-
+ * This Source Code Form is subject to the terms of the Mozilla Public
+ * License, v. 2.0. If a copy of the MPL was not distributed with this
+ * file, You can obtain one at http://mozilla.org/MPL/2.0/. */
+
+package org.mozilla.gecko;
+
+import android.annotation.SuppressLint;
+import android.content.BroadcastReceiver;
+import android.content.Context;
+import android.content.Intent;
+import android.content.IntentFilter;
+import android.net.ConnectivityManager;
+import android.net.DhcpInfo;
+import android.net.wifi.WifiManager;
+import android.util.Log;
+import androidx.annotation.NonNull;
+import androidx.annotation.Nullable;
+import org.mozilla.gecko.annotation.WrapForJNI;
+import org.mozilla.gecko.util.NetworkUtils;
+import org.mozilla.gecko.util.NetworkUtils.ConnectionSubType;
+import org.mozilla.gecko.util.NetworkUtils.ConnectionType;
+import org.mozilla.gecko.util.NetworkUtils.NetworkStatus;
+
+/**
+ * Provides connection type, subtype and general network status (up/down).
+ *
+ * <p>According to spec of Network Information API version 3, connection types include: bluetooth,
+ * cellular, ethernet, none, wifi and other. The objective of providing such general connection is
+ * due to some security concerns. In short, we don't want to expose exact network type, especially
+ * the cellular network type.
+ *
+ * <p>Specific mobile subtypes are mapped to general 2G, 3G and 4G buckets.
+ *
+ * <p>Logic is implemented as a state machine, so see the transition matrix to figure out what
+ * happens when. This class depends on access to the context, so only use after GeckoAppShell has
+ * been initialized.
+ */
+public class GeckoNetworkManager extends BroadcastReceiver {
+  private static final String LOGTAG = "GeckoNetworkManager";
+
+  // If network configuration and/or status changed, we send details of what changed.
+  // If we received a "check out new network state!" intent from the OS but nothing in it looks
+  // different, we ignore it. See Bug 1330836 for some relevant details.
+  private static final String LINK_DATA_CHANGED = "changed";
+
+  private static GeckoNetworkManager instance;
+
+  // We hackishly (yet harmlessly, in this case) keep a Context reference passed in via the start
+  // method.
+  // See context handling notes in handleManagerEvent, and Bug 1277333.
+  private Context mContext;
+
+  public static void destroy() {
+    if (instance != null) {
+      instance.onDestroy();
+      instance = null;
+    }
+  }
+
+  public enum ManagerState {
+    OffNoListeners,
+    OffWithListeners,
+    OnNoListeners,
+    OnWithListeners
+  }
+
+  public enum ManagerEvent {
+    start,
+    stop,
+    enableNotifications,
+    disableNotifications,
+    receivedUpdate
+  }
+
+  private ManagerState mCurrentState = ManagerState.OffNoListeners;
+  private ConnectionType mCurrentConnectionType = ConnectionType.NONE;
+  private ConnectionType mPreviousConnectionType = ConnectionType.NONE;
+  private ConnectionSubType mCurrentConnectionSubtype = ConnectionSubType.UNKNOWN;
+  private ConnectionSubType mPreviousConnectionSubtype = ConnectionSubType.UNKNOWN;
+  private NetworkStatus mCurrentNetworkStatus = NetworkStatus.UNKNOWN;
+  private NetworkStatus mPreviousNetworkStatus = NetworkStatus.UNKNOWN;
+
+  private GeckoNetworkManager() {}
+
+  private void onDestroy() {
+    handleManagerEvent(ManagerEvent.stop);
+  }
+
+  public static GeckoNetworkManager getInstance() {
+    if (instance == null) {
+      instance = new GeckoNetworkManager();
+    }
+
+    return instance;
+  }
+
+  public double[] getCurrentInformation() {
+    final Context applicationContext = GeckoAppShell.getApplicationContext();
+    final ConnectionType connectionType = mCurrentConnectionType;
+    return new double[] {
+      connectionType.value,
+      connectionType == ConnectionType.WIFI ? 1.0 : 0.0,
+      connectionType == ConnectionType.WIFI ? wifiDhcpGatewayAddress(applicationContext) : 0.0
+    };
+  }
+
+  @Override
+  public void onReceive(final Context aContext, final Intent aIntent) {
+    handleManagerEvent(ManagerEvent.receivedUpdate);
+  }
+
+  public void start(final Context context) {
+    mContext = context;
+    handleManagerEvent(ManagerEvent.start);
+  }
+
+  public void stop() {
+    handleManagerEvent(ManagerEvent.stop);
+  }
+
+  public void enableNotifications() {
+    handleManagerEvent(ManagerEvent.enableNotifications);
+  }
+
+  public void disableNotifications() {
+    handleManagerEvent(ManagerEvent.disableNotifications);
+  }
+
+  /**
+   * For a given event, figure out the next state, run any transition by-product actions, and switch
+   * current state to the next state. If event is invalid for the current state, this is a no-op.
+   *
+   * @param event Incoming event
+   * @return Boolean indicating if transition was performed.
+   */
+  private synchronized boolean handleManagerEvent(final ManagerEvent event) {
+    final ManagerState nextState = getNextState(mCurrentState, event);
+
+    Log.d(LOGTAG, "Incoming event " + event + " for state " + mCurrentState + " -> " + nextState);
+    if (nextState == null) {
+      Log.w(LOGTAG, "Invalid event " + event + " for state " + mCurrentState);
+      return false;
+    }
+
+    // We're being deliberately careful about handling context here; it's possible that in some
+    // rare cases and possibly related to timing of when this is called (seems to be early in the
+    // startup phase),
+    // GeckoAppShell.getApplicationContext() will be null, and .start() wasn't called yet,
+    // so we don't have a local Context reference either. If both of these are true, we have to drop
+    // the event.
+    // NB: this is hacky (and these checks attempt to isolate the hackiness), and root cause
+    // seems to be how this class fits into the larger ecosystem and general flow of events.
+    // See Bug 1277333.
+    final Context contextForAction;
+    if (mContext != null) {
+      contextForAction = mContext;
+    } else {
+      contextForAction = GeckoAppShell.getApplicationContext();
+    }
+
+    if (contextForAction == null) {
+      Log.w(
+          LOGTAG,
+          "Context is not available while processing event "
+              + event
+              + " for state "
+              + mCurrentState);
+      return false;
+    }
+
+    performActionsForStateEvent(contextForAction, mCurrentState, event);
+    mCurrentState = nextState;
+
+    return true;
+  }
+
+  /**
+   * Defines a transition matrix for our state machine. For a given state/event pair, returns
+   * nextState.
+   *
+   * @param currentState Current state against which we have an incoming event
+   * @param event Incoming event for which we'd like to figure out the next state
+   * @return State into which we should transition as result of given event
+   */
+  @Nullable
+  public static ManagerState getNextState(
+      final @NonNull ManagerState currentState, final @NonNull ManagerEvent event) {
+    switch (currentState) {
+      case OffNoListeners:
+        switch (event) {
+          case start:
+            return ManagerState.OnNoListeners;
+          case enableNotifications:
+            return ManagerState.OffWithListeners;
+          default:
+            return null;
+        }
+      case OnNoListeners:
+        switch (event) {
+          case stop:
+            return ManagerState.OffNoListeners;
+          case enableNotifications:
+            return ManagerState.OnWithListeners;
+          case receivedUpdate:
+            return ManagerState.OnNoListeners;
+          default:
+            return null;
+        }
+      case OnWithListeners:
+        switch (event) {
+          case stop:
+            return ManagerState.OffWithListeners;
+          case disableNotifications:
+            return ManagerState.OnNoListeners;
+          case receivedUpdate:
+            return ManagerState.OnWithListeners;
+          default:
+            return null;
+        }
+      case OffWithListeners:
+        switch (event) {
+          case start:
+            return ManagerState.OnWithListeners;
+          case disableNotifications:
+            return ManagerState.OffNoListeners;
+          default:
+            return null;
+        }
+      default:
+        throw new IllegalStateException("Unknown current state: " + currentState.name());
+    }
+  }
+
+  /**
+   * For a given state/event combination, run any actions which are by-products of leaving the state
+   * because of a given event. Since this is a deterministic state machine, we can easily do that
+   * without any additional information.
+   *
+   * @param currentState State which we are leaving
+   * @param event Event which is causing us to leave the state
+   */
+  private void performActionsForStateEvent(
+      final Context context, final ManagerState currentState, final ManagerEvent event) {
+    // NB: network state might be queried via getCurrentInformation at any time; pre-rewrite
+    // behaviour was
+    // that network state was updated whenever enableNotifications was called. To avoid deviating
+    // from previous behaviour and causing weird side-effects, we call
+    // updateNetworkStateAndConnectionType
+    // whenever notifications are enabled.
+    switch (currentState) {
+      case OffNoListeners:
+        if (event == ManagerEvent.start) {
+          updateNetworkStateAndConnectionType(context);
+          registerBroadcastReceiver(context, this);
+        }
+        if (event == ManagerEvent.enableNotifications) {
+          updateNetworkStateAndConnectionType(context);
+        }
+        break;
+      case OnNoListeners:
+        if (event == ManagerEvent.receivedUpdate) {
+          updateNetworkStateAndConnectionType(context);
+          sendNetworkStateToListeners(context);
+        }
+        if (event == ManagerEvent.enableNotifications) {
+          updateNetworkStateAndConnectionType(context);
+          registerBroadcastReceiver(context, this);
+        }
+        if (event == ManagerEvent.stop) {
+          unregisterBroadcastReceiver(context, this);
+        }
+        break;
+      case OnWithListeners:
+        if (event == ManagerEvent.receivedUpdate) {
+          updateNetworkStateAndConnectionType(context);
+          sendNetworkStateToListeners(context);
+        }
+        if (event == ManagerEvent.stop) {
+          unregisterBroadcastReceiver(context, this);
+        }
+        /* no-op event: ManagerEvent.disableNotifications */
+        break;
+      case OffWithListeners:
+        if (event == ManagerEvent.start) {
+          registerBroadcastReceiver(context, this);
+        }
+        /* no-op event: ManagerEvent.disableNotifications */
+        break;
+      default:
+        throw new IllegalStateException("Unknown current state: " + currentState.name());
+    }
+  }
+
+  /** Update current network state and connection types. */
+  private void updateNetworkStateAndConnectionType(final Context context) {
+    final ConnectivityManager connectivityManager =
+        (ConnectivityManager) context.getSystemService(Context.CONNECTIVITY_SERVICE);
+    // Type/status getters below all have a defined behaviour for when connectivityManager == null
+    if (connectivityManager == null) {
+      Log.e(LOGTAG, "ConnectivityManager does not exist.");
+    }
+    mCurrentConnectionType = NetworkUtils.getConnectionType(connectivityManager);
+    mCurrentNetworkStatus = NetworkUtils.getNetworkStatus(connectivityManager);
+    mCurrentConnectionSubtype = NetworkUtils.getConnectionSubType(connectivityManager);
+    Log.d(
+        LOGTAG,
+        "New network state: "
+            + mCurrentNetworkStatus
+            + ", "
+            + mCurrentConnectionType
+            + ", "
+            + mCurrentConnectionSubtype);
+  }
+
+  @WrapForJNI(dispatchTo = "gecko")
+  private static native void onConnectionChanged(
+      int type, String subType, boolean isWifi, int dhcpGateway);
+
+  @WrapForJNI(dispatchTo = "gecko")
+  private static native void onStatusChanged(String status);
+
+  /** Send current network state and connection type to whomever is listening. */
+  private void sendNetworkStateToListeners(final Context context) {
+    final boolean connectionTypeOrSubtypeChanged =
+        mCurrentConnectionType != mPreviousConnectionType
+            || mCurrentConnectionSubtype != mPreviousConnectionSubtype;
+    if (connectionTypeOrSubtypeChanged) {
+      mPreviousConnectionType = mCurrentConnectionType;
+      mPreviousConnectionSubtype = mCurrentConnectionSubtype;
+
+      final boolean isWifi = mCurrentConnectionType == ConnectionType.WIFI;
+      final int gateway = !isWifi ? 0 : wifiDhcpGatewayAddress(context);
+
+      if (GeckoThread.isRunning()) {
+        onConnectionChanged(
+            mCurrentConnectionType.value, mCurrentConnectionSubtype.value, isWifi, gateway);
+      } else {
+        GeckoThread.queueNativeCall(
+            GeckoNetworkManager.class,
+            "onConnectionChanged",
+            mCurrentConnectionType.value,
+            String.class,
+            mCurrentConnectionSubtype.value,
+            isWifi,
+            gateway);
+      }
+    }
+
+    // If neither network status nor network configuration changed, do nothing.
+    if (mCurrentNetworkStatus == mPreviousNetworkStatus && !connectionTypeOrSubtypeChanged) {
+      return;
+    }
+
+    // If network status remains the same, send "changed". Otherwise, send new network status.
+    // See Bug 1330836 for relevant details.
+    final String status;
+    if (mCurrentNetworkStatus == mPreviousNetworkStatus) {
+      status = LINK_DATA_CHANGED;
+    } else {
+      mPreviousNetworkStatus = mCurrentNetworkStatus;
+      status = mCurrentNetworkStatus.value;
+    }
+
+    if (GeckoThread.isRunning()) {
+      onStatusChanged(status);
+    } else {
+      GeckoThread.queueNativeCall(
+          GeckoNetworkManager.class, "onStatusChanged", String.class, status);
+    }
+  }
+
+  /** Stop listening for network state updates. */
+  private static void unregisterBroadcastReceiver(
+      final Context context, final BroadcastReceiver receiver) {
+    context.unregisterReceiver(receiver);
+  }
+
+  /** Start listening for network state updates. */
+  private static void registerBroadcastReceiver(
+      final Context context, final BroadcastReceiver receiver) {
+    final IntentFilter filter = new IntentFilter(ConnectivityManager.CONNECTIVITY_ACTION);
+    context.registerReceiver(receiver, filter);
+  }
+
+  private static int wifiDhcpGatewayAddress(final Context context) {
+    if (context == null) {
+      return 0;
+    }
+
+    try {
+      final WifiManager mgr =
+          (WifiManager) context.getApplicationContext().getSystemService(Context.WIFI_SERVICE);
+      if (mgr == null) {
+        return 0;
+      }
+
+      @SuppressLint("MissingPermission")
+      final DhcpInfo d = mgr.getDhcpInfo();
+      if (d == null) {
+        return 0;
+      }
+
+      return d.gateway;
+
+    } catch (final Exception ex) {
+      // getDhcpInfo() is not documented to require any permissions, but on some devices
+      // requires android.permission.ACCESS_WIFI_STATE. Just catch the generic exception
+      // here and returning 0. Not logging because this could be noisy.
+      return 0;
+    }
+  }
+}