NetworkStackClient: Refactor network stack process interaction

Refactor NetworkStackClient class to move the module service binding &
network stack process death monitoring to a separate class. This class
will only instantiated in the SystemServer process.
The new class |SystemServerToNetworkStackConnector| will be used from
the client classes corresponding to each module running on the network
stack process (NetworkStackClient, WifiStackClient, etc)

This has 2 main advantages:
a) Reduces code duplication (Otherwise the various Client classes need
to replicate the service bindding & process death monitoring).
b) Central crash recovery for the network stack process (Otherwise the
various Client classes will trigger multiple recovery for a single
network stack process crash).

Bug: 135679762
Test: Device boots up & connects to wifi networks.
Change-Id: I673581b0067b9a3f72dd68a3ab622c18183ebd2e
Merged-In: I673581b0067b9a3f72dd68a3ab622c18183ebd2e
(cherry picked from commit 7e6f5f5e080f2d2ae3ef0397c21bd666f5ce4d31)

2 files changed, 398 insertions, 240 deletions

diff --git a/services/net/java/android/net/ConnectivityModuleConnector.java b/services/net/java/android/net/ConnectivityModuleConnector.java
new file mode 100644
index 000000000000..7333f583e8e8
--- /dev/null
+++ b/services/net/java/android/net/ConnectivityModuleConnector.java
@@ -0,0 +1,389 @@
+/*
+ * Copyright (C) 2019 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;
+
+import static android.content.pm.PackageManager.PERMISSION_GRANTED;
+
+import android.annotation.NonNull;
+import android.annotation.Nullable;
+import android.content.ComponentName;
+import android.content.Context;
+import android.content.Intent;
+import android.content.ServiceConnection;
+import android.content.SharedPreferences;
+import android.content.pm.PackageManager;
+import android.net.util.SharedLog;
+import android.os.Build;
+import android.os.Environment;
+import android.os.IBinder;
+import android.os.Process;
+import android.os.SystemClock;
+import android.os.UserHandle;
+import android.provider.DeviceConfig;
+import android.text.format.DateUtils;
+import android.util.ArraySet;
+import android.util.Slog;
+
+import com.android.internal.annotations.GuardedBy;
+
+import java.io.File;
+import java.io.PrintWriter;
+
+/**
+ * Class used to communicate to the various networking mainline modules running in the network stack
+ * process from {@link com.android.server.SystemServer}.
+ * @hide
+ */
+public class ConnectivityModuleConnector {
+    private static final String TAG = ConnectivityModuleConnector.class.getSimpleName();
+    private static final String IN_PROCESS_SUFFIX = ".InProcess";
+
+    private static final String PREFS_FILE = "ConnectivityModuleConnector.xml";
+    private static final String PREF_KEY_LAST_CRASH_TIME = "lastcrash_time";
+    private static final String CONFIG_MIN_CRASH_INTERVAL_MS = "min_crash_interval";
+    private static final String CONFIG_MIN_UPTIME_BEFORE_CRASH_MS = "min_uptime_before_crash";
+    private static final String CONFIG_ALWAYS_RATELIMIT_NETWORKSTACK_CRASH =
+            "always_ratelimit_networkstack_crash";
+
+    // Even if the network stack is lost, do not crash the system more often than this.
+    // Connectivity would be broken, but if the user needs the device for something urgent
+    // (like calling emergency services) we should not bootloop the device.
+    // This is the default value: the actual value can be adjusted via device config.
+    private static final long DEFAULT_MIN_CRASH_INTERVAL_MS = 6 * DateUtils.HOUR_IN_MILLIS;
+
+    // Even if the network stack is lost, do not crash the system server if it was less than
+    // this much after boot. This avoids bootlooping the device, and crashes should address very
+    // infrequent failures, not failures on boot.
+    private static final long DEFAULT_MIN_UPTIME_BEFORE_CRASH_MS = 30 * DateUtils.MINUTE_IN_MILLIS;
+
+    private static ConnectivityModuleConnector sInstance;
+
+    private Context mContext;
+    @GuardedBy("mLog")
+    private final SharedLog mLog = new SharedLog(TAG);
+    @GuardedBy("mHealthListeners")
+    private final ArraySet<ConnectivityModuleHealthListener> mHealthListeners = new ArraySet<>();
+
+    private ConnectivityModuleConnector() { }
+
+    /**
+     * Get the {@link ConnectivityModuleConnector} singleton instance.
+     */
+    public static synchronized ConnectivityModuleConnector getInstance() {
+        if (sInstance == null) {
+            sInstance = new ConnectivityModuleConnector();
+        }
+        return sInstance;
+    }
+
+    /**
+     * Initialize the network stack connector. Should be called only once on device startup, before
+     * any client attempts to use the network stack.
+     */
+    public void init(Context context) {
+        log("Network stack init");
+        mContext = context;
+    }
+
+    /**
+     * Callback interface for severe failures of the NetworkStack.
+     *
+     * <p>Useful for health monitors such as PackageWatchdog.
+     */
+    public interface ConnectivityModuleHealthListener {
+        /**
+         * Called when there is a severe failure of the network stack.
+         * @param packageName Package name of the network stack.
+         */
+        void onNetworkStackFailure(@NonNull String packageName);
+    }
+
+    /**
+     * Callback invoked by the connector once the connection to the corresponding module is
+     * established.
+     */
+    public interface ModuleServiceCallback {
+        /**
+         * Invoked when the corresponding service has connected.
+         *
+         * @param iBinder Binder object for the service.
+         */
+        void onModuleServiceConnected(@NonNull IBinder iBinder);
+    }
+
+
+    /**
+     * Add a {@link ConnectivityModuleHealthListener} to listen to network stack health events.
+     */
+    public void registerHealthListener(@NonNull ConnectivityModuleHealthListener listener) {
+        synchronized (mHealthListeners) {
+            mHealthListeners.add(listener);
+        }
+    }
+
+    /**
+     * Start a module running in the network stack or system_server process. Should be called only
+     * once for each module per device startup.
+     *
+     * <p>This method will start a networking module either in the network stack
+     * process, or inside the system server on devices that do not support the corresponding
+     * mainline network . The corresponding networking module service's binder
+     * object will then be delivered asynchronously via the provided {@link ModuleServiceCallback}.
+     *
+     * @param serviceIntentBaseAction Base action to use for constructing the intent needed to
+     *                                bind to the corresponding module.
+     * @param servicePermissionName Permission to be held by the corresponding module.
+     */
+    public void startModuleService(
+            @NonNull String serviceIntentBaseAction,
+            @NonNull String servicePermissionName,
+            @NonNull ModuleServiceCallback callback) {
+        log("Starting networking module " + serviceIntentBaseAction);
+
+        final PackageManager pm = mContext.getPackageManager();
+
+        // Try to bind in-process if the device was shipped with an in-process version
+        Intent intent = getModuleServiceIntent(pm, serviceIntentBaseAction, servicePermissionName,
+                true /* inSystemProcess */);
+
+        // Otherwise use the updatable module version
+        if (intent == null) {
+            intent = getModuleServiceIntent(pm, serviceIntentBaseAction, servicePermissionName,
+                false /* inSystemProcess */);
+            log("Starting networking module in network_stack process");
+        } else {
+            log("Starting networking module in system_server process");
+        }
+
+        if (intent == null) {
+            maybeCrashWithTerribleFailure("Could not resolve the networking module", null);
+            return;
+        }
+
+        final String packageName = intent.getComponent().getPackageName();
+
+        // Start the network stack. The service will be added to the service manager by the
+        // corresponding client in ModuleServiceCallback.onModuleServiceConnected().
+        if (!mContext.bindServiceAsUser(
+                intent, new ModuleServiceConnection(packageName, callback),
+                Context.BIND_AUTO_CREATE | Context.BIND_IMPORTANT, UserHandle.SYSTEM)) {
+            maybeCrashWithTerribleFailure(
+                    "Could not bind to networking module in-process, or in app with "
+                            + intent, packageName);
+            return;
+        }
+
+        log("Networking module service start requested");
+    }
+
+    private class ModuleServiceConnection implements ServiceConnection {
+        @NonNull
+        private final String mPackageName;
+        @NonNull
+        private final ModuleServiceCallback mModuleServiceCallback;
+
+        private ModuleServiceConnection(
+                @NonNull String packageName,
+                @NonNull ModuleServiceCallback moduleCallback) {
+            mPackageName = packageName;
+            mModuleServiceCallback = moduleCallback;
+        }
+
+        @Override
+        public void onServiceConnected(ComponentName name, IBinder service) {
+            logi("Networking module service connected");
+            mModuleServiceCallback.onModuleServiceConnected(service);
+        }
+
+        @Override
+        public void onServiceDisconnected(ComponentName name) {
+            // onServiceDisconnected is not being called on device shutdown, so this method being
+            // called always indicates a bad state for the system server.
+            // This code path is only run by the system server: only the system server binds
+            // to the NetworkStack as a service. Other processes get the NetworkStack from
+            // the ServiceManager.
+            maybeCrashWithTerribleFailure("Lost network stack", mPackageName);
+        }
+    }
+
+    @Nullable
+    private Intent getModuleServiceIntent(
+            @NonNull PackageManager pm, @NonNull String serviceIntentBaseAction,
+            @NonNull String servicePermissionName, boolean inSystemProcess) {
+        final Intent intent =
+                new Intent(inSystemProcess
+                        ? serviceIntentBaseAction + IN_PROCESS_SUFFIX
+                        : serviceIntentBaseAction);
+        final ComponentName comp = intent.resolveSystemService(pm, 0);
+        if (comp == null) {
+            return null;
+        }
+        intent.setComponent(comp);
+
+        int uid = -1;
+        try {
+            uid = pm.getPackageUidAsUser(comp.getPackageName(), UserHandle.USER_SYSTEM);
+        } catch (PackageManager.NameNotFoundException e) {
+            logWtf("Networking module package not found", e);
+            // Fall through
+        }
+
+        final int expectedUid = inSystemProcess ? Process.SYSTEM_UID : Process.NETWORK_STACK_UID;
+        if (uid != expectedUid) {
+            throw new SecurityException("Invalid network stack UID: " + uid);
+        }
+
+        if (!inSystemProcess) {
+            checkModuleServicePermission(pm, comp, servicePermissionName);
+        }
+
+        return intent;
+    }
+
+    private void checkModuleServicePermission(
+            @NonNull PackageManager pm, @NonNull ComponentName comp,
+            @NonNull String servicePermissionName) {
+        final int hasPermission =
+                pm.checkPermission(servicePermissionName, comp.getPackageName());
+        if (hasPermission != PERMISSION_GRANTED) {
+            throw new SecurityException(
+                    "Networking module does not have permission " + servicePermissionName);
+        }
+    }
+
+    private synchronized void maybeCrashWithTerribleFailure(@NonNull String message,
+            @Nullable String packageName) {
+        logWtf(message, null);
+        // uptime is monotonic even after a framework restart
+        final long uptime = SystemClock.elapsedRealtime();
+        final long now = System.currentTimeMillis();
+        final long minCrashIntervalMs = DeviceConfig.getLong(DeviceConfig.NAMESPACE_CONNECTIVITY,
+                CONFIG_MIN_CRASH_INTERVAL_MS, DEFAULT_MIN_CRASH_INTERVAL_MS);
+        final long minUptimeBeforeCrash = DeviceConfig.getLong(DeviceConfig.NAMESPACE_CONNECTIVITY,
+                CONFIG_MIN_UPTIME_BEFORE_CRASH_MS, DEFAULT_MIN_UPTIME_BEFORE_CRASH_MS);
+        final boolean alwaysRatelimit = DeviceConfig.getBoolean(DeviceConfig.NAMESPACE_CONNECTIVITY,
+                CONFIG_ALWAYS_RATELIMIT_NETWORKSTACK_CRASH, false);
+
+        final SharedPreferences prefs = getSharedPreferences();
+        final long lastCrashTime = tryGetLastCrashTime(prefs);
+
+        // Only crash if there was enough time since boot, and (if known) enough time passed since
+        // the last crash.
+        // time and lastCrashTime may be unreliable if devices have incorrect clock time, but they
+        // are only used to limit the number of crashes compared to only using the time since boot,
+        // which would also be OK behavior by itself.
+        // - If lastCrashTime is incorrectly more than the current time, only look at uptime
+        // - If it is much less than current time, only look at uptime
+        // - If current time is during the next few hours after last crash time, don't crash.
+        //   Considering that this only matters if last boot was some time ago, it's likely that
+        //   time will be set correctly. Otherwise, not crashing is not a big problem anyway. Being
+        //   in this last state would also not last for long since the window is only a few hours.
+        final boolean alwaysCrash = Build.IS_DEBUGGABLE && !alwaysRatelimit;
+        final boolean justBooted = uptime < minUptimeBeforeCrash;
+        final boolean haveLastCrashTime = (lastCrashTime != 0) && (lastCrashTime < now);
+        final boolean haveKnownRecentCrash =
+                haveLastCrashTime && (now < lastCrashTime + minCrashIntervalMs);
+        if (alwaysCrash || (!justBooted && !haveKnownRecentCrash)) {
+            // The system is not bound to its network stack (for example due to a crash in the
+            // network stack process): better crash rather than stay in a bad state where all
+            // networking is broken.
+            // Using device-encrypted SharedPreferences as DeviceConfig does not have a synchronous
+            // API to persist settings before a crash.
+            tryWriteLastCrashTime(prefs, now);
+            throw new IllegalStateException(message);
+        }
+
+        // Here the system crashed recently already. Inform listeners that something is
+        // definitely wrong.
+        if (packageName != null) {
+            final ArraySet<ConnectivityModuleHealthListener> listeners;
+            synchronized (mHealthListeners) {
+                listeners = new ArraySet<>(mHealthListeners);
+            }
+            for (ConnectivityModuleHealthListener listener : listeners) {
+                listener.onNetworkStackFailure(packageName);
+            }
+        }
+    }
+
+    @Nullable
+    private SharedPreferences getSharedPreferences() {
+        try {
+            final File prefsFile = new File(
+                    Environment.getDataSystemDeDirectory(UserHandle.USER_SYSTEM), PREFS_FILE);
+            return mContext.createDeviceProtectedStorageContext()
+                    .getSharedPreferences(prefsFile, Context.MODE_PRIVATE);
+        } catch (Throwable e) {
+            logWtf("Error loading shared preferences", e);
+            return null;
+        }
+    }
+
+    private long tryGetLastCrashTime(@Nullable SharedPreferences prefs) {
+        if (prefs == null) return 0L;
+        try {
+            return prefs.getLong(PREF_KEY_LAST_CRASH_TIME, 0L);
+        } catch (Throwable e) {
+            logWtf("Error getting last crash time", e);
+            return 0L;
+        }
+    }
+
+    private void tryWriteLastCrashTime(@Nullable SharedPreferences prefs, long value) {
+        if (prefs == null) return;
+        try {
+            prefs.edit().putLong(PREF_KEY_LAST_CRASH_TIME, value).commit();
+        } catch (Throwable e) {
+            logWtf("Error writing last crash time", e);
+        }
+    }
+
+    private void log(@NonNull String message) {
+        Slog.d(TAG, message);
+        synchronized (mLog) {
+            mLog.log(message);
+        }
+    }
+
+    private void logWtf(@NonNull String message, @Nullable Throwable e) {
+        Slog.wtf(TAG, message, e);
+        synchronized (mLog) {
+            mLog.e(message);
+        }
+    }
+
+    private void loge(@NonNull String message, @Nullable Throwable e) {
+        Slog.e(TAG, message, e);
+        synchronized (mLog) {
+            mLog.e(message);
+        }
+    }
+
+    private void logi(@NonNull String message) {
+        Slog.i(TAG, message);
+        synchronized (mLog) {
+            mLog.i(message);
+        }
+    }
+
+    /**
+     * Dump ConnectivityModuleConnector logs to the specified {@link PrintWriter}.
+     */
+    public void dump(PrintWriter pw) {
+        // dump is thread-safe on SharedLog
+        mLog.dump(null, pw, null);
+    }
+}
diff --git a/services/net/java/android/net/NetworkStackClient.java b/services/net/java/android/net/NetworkStackClient.java
index 56b728c87180..abb46664e40d 100644
--- a/services/net/java/android/net/NetworkStackClient.java
+++ b/services/net/java/android/net/NetworkStackClient.java
@@ -15,40 +15,27 @@
  */
 package android.net;
 
-import static android.content.pm.PackageManager.PERMISSION_GRANTED;
 import static android.net.NetworkStack.PERMISSION_MAINLINE_NETWORK_STACK;
 import static android.os.IServiceManager.DUMP_FLAG_PRIORITY_HIGH;
 import static android.os.IServiceManager.DUMP_FLAG_PRIORITY_NORMAL;
 
 import android.annotation.NonNull;
 import android.annotation.Nullable;
-import android.content.ComponentName;
 import android.content.Context;
-import android.content.Intent;
-import android.content.ServiceConnection;
-import android.content.SharedPreferences;
-import android.content.pm.PackageManager;
 import android.net.dhcp.DhcpServingParamsParcel;
 import android.net.dhcp.IDhcpServerCallbacks;
 import android.net.ip.IIpClientCallbacks;
 import android.net.util.SharedLog;
 import android.os.Binder;
-import android.os.Build;
-import android.os.Environment;
 import android.os.IBinder;
 import android.os.Process;
 import android.os.RemoteException;
 import android.os.ServiceManager;
-import android.os.SystemClock;
 import android.os.UserHandle;
-import android.provider.DeviceConfig;
-import android.text.format.DateUtils;
-import android.util.ArraySet;
 import android.util.Slog;
 
 import com.android.internal.annotations.GuardedBy;
 
-import java.io.File;
 import java.io.PrintWriter;
 import java.util.ArrayList;
 
@@ -60,24 +47,6 @@ public class NetworkStackClient {
     private static final String TAG = NetworkStackClient.class.getSimpleName();
 
     private static final int NETWORKSTACK_TIMEOUT_MS = 10_000;
-    private static final String IN_PROCESS_SUFFIX = ".InProcess";
-    private static final String PREFS_FILE = "NetworkStackClientPrefs.xml";
-    private static final String PREF_KEY_LAST_CRASH_TIME = "lastcrash_time";
-    private static final String CONFIG_MIN_CRASH_INTERVAL_MS = "min_crash_interval";
-    private static final String CONFIG_MIN_UPTIME_BEFORE_CRASH_MS = "min_uptime_before_crash";
-    private static final String CONFIG_ALWAYS_RATELIMIT_NETWORKSTACK_CRASH =
-            "always_ratelimit_networkstack_crash";
-
-    // Even if the network stack is lost, do not crash the system more often than this.
-    // Connectivity would be broken, but if the user needs the device for something urgent
-    // (like calling emergency services) we should not bootloop the device.
-    // This is the default value: the actual value can be adjusted via device config.
-    private static final long DEFAULT_MIN_CRASH_INTERVAL_MS = 6 * DateUtils.HOUR_IN_MILLIS;
-
-    // Even if the network stack is lost, do not crash the system server if it was less than
-    // this much after boot. This avoids bootlooping the device, and crashes should address very
-    // infrequent failures, not failures on boot.
-    private static final long DEFAULT_MIN_UPTIME_BEFORE_CRASH_MS = 30 * DateUtils.MINUTE_IN_MILLIS;
 
     private static NetworkStackClient sInstance;
 
@@ -93,26 +62,10 @@ public class NetworkStackClient {
 
     private volatile boolean mWasSystemServerInitialized = false;
 
-    @GuardedBy("mHealthListeners")
-    private final ArraySet<NetworkStackHealthListener> mHealthListeners = new ArraySet<>();
-
     private interface NetworkStackCallback {
         void onNetworkStackConnected(INetworkStackConnector connector);
     }
 
-    /**
-     * Callback interface for severe failures of the NetworkStack.
-     *
-     * <p>Useful for health monitors such as PackageWatchdog.
-     */
-    public interface NetworkStackHealthListener {
-        /**
-         * Called when there is a severe failure of the network stack.
-         * @param packageName Package name of the network stack.
-         */
-        void onNetworkStackFailure(@NonNull String packageName);
-    }
-
     private NetworkStackClient() { }
 
     /**
@@ -126,15 +79,6 @@ public class NetworkStackClient {
     }
 
     /**
-     * Add a {@link NetworkStackHealthListener} to listen to network stack health events.
-     */
-    public void registerHealthListener(@NonNull NetworkStackHealthListener listener) {
-        synchronized (mHealthListeners) {
-            mHealthListeners.add(listener);
-        }
-    }
-
-    /**
      * Create a DHCP server according to the specified parameters.
      *
      * <p>The server will be returned asynchronously through the provided callbacks.
@@ -195,32 +139,13 @@ public class NetworkStackClient {
         });
     }
 
-    private class NetworkStackConnection implements ServiceConnection {
-        @NonNull
-        private final Context mContext;
-        @NonNull
-        private final String mPackageName;
-
-        private NetworkStackConnection(@NonNull Context context, @NonNull String packageName) {
-            mContext = context;
-            mPackageName = packageName;
-        }
-
+    private class NetworkStackConnection implements
+            ConnectivityModuleConnector.ModuleServiceCallback {
         @Override
-        public void onServiceConnected(ComponentName name, IBinder service) {
+        public void onModuleServiceConnected(IBinder service) {
             logi("Network stack service connected");
             registerNetworkStackService(service);
         }
-
-        @Override
-        public void onServiceDisconnected(ComponentName name) {
-            // onServiceDisconnected is not being called on device shutdown, so this method being
-            // called always indicates a bad state for the system server.
-            // This code path is only run by the system server: only the system server binds
-            // to the NetworkStack as a service. Other processes get the NetworkStack from
-            // the ServiceManager.
-            maybeCrashWithTerribleFailure("Lost network stack", mContext, mPackageName);
-        }
     }
 
     private void registerNetworkStackService(@NonNull IBinder service) {
@@ -259,171 +184,13 @@ public class NetworkStackClient {
      * connector will then be delivered asynchronously to clients that requested it before it was
      * started.
      */
-    public void start(Context context) {
-        log("Starting network stack");
-
-        final PackageManager pm = context.getPackageManager();
-
-        // Try to bind in-process if the device was shipped with an in-process version
-        Intent intent = getNetworkStackIntent(pm, true /* inSystemProcess */);
-
-        // Otherwise use the updatable module version
-        if (intent == null) {
-            intent = getNetworkStackIntent(pm, false /* inSystemProcess */);
-            log("Starting network stack process");
-        } else {
-            log("Starting network stack in-process");
-        }
-
-        if (intent == null) {
-            maybeCrashWithTerribleFailure("Could not resolve the network stack", context, null);
-            return;
-        }
-
-        final String packageName = intent.getComponent().getPackageName();
-
-        // Start the network stack. The service will be added to the service manager in
-        // NetworkStackConnection.onServiceConnected().
-        if (!context.bindServiceAsUser(intent, new NetworkStackConnection(context, packageName),
-                Context.BIND_AUTO_CREATE | Context.BIND_IMPORTANT, UserHandle.SYSTEM)) {
-            maybeCrashWithTerribleFailure(
-                    "Could not bind to network stack in-process, or in app with " + intent,
-                    context, packageName);
-            return;
-        }
-
+    public void start() {
+        ConnectivityModuleConnector.getInstance().startModuleService(
+                INetworkStackConnector.class.getName(), PERMISSION_MAINLINE_NETWORK_STACK,
+                new NetworkStackConnection());
         log("Network stack service start requested");
     }
 
-    @Nullable
-    private Intent getNetworkStackIntent(@NonNull PackageManager pm, boolean inSystemProcess) {
-        final String baseAction = INetworkStackConnector.class.getName();
-        final Intent intent =
-                new Intent(inSystemProcess ? baseAction + IN_PROCESS_SUFFIX : baseAction);
-        final ComponentName comp = intent.resolveSystemService(pm, 0);
-
-        if (comp == null) {
-            return null;
-        }
-        intent.setComponent(comp);
-
-        int uid = -1;
-        try {
-            uid = pm.getPackageUidAsUser(comp.getPackageName(), UserHandle.USER_SYSTEM);
-        } catch (PackageManager.NameNotFoundException e) {
-            logWtf("Network stack package not found", e);
-            // Fall through
-        }
-
-        final int expectedUid = inSystemProcess ? Process.SYSTEM_UID : Process.NETWORK_STACK_UID;
-        if (uid != expectedUid) {
-            throw new SecurityException("Invalid network stack UID: " + uid);
-        }
-
-        if (!inSystemProcess) {
-            checkNetworkStackPermission(pm, comp);
-        }
-
-        return intent;
-    }
-
-    private void checkNetworkStackPermission(
-            @NonNull PackageManager pm, @NonNull ComponentName comp) {
-        final int hasPermission =
-                pm.checkPermission(PERMISSION_MAINLINE_NETWORK_STACK, comp.getPackageName());
-        if (hasPermission != PERMISSION_GRANTED) {
-            throw new SecurityException(
-                    "Network stack does not have permission " + PERMISSION_MAINLINE_NETWORK_STACK);
-        }
-    }
-
-    private void maybeCrashWithTerribleFailure(@NonNull String message,
-            @NonNull Context context, @Nullable String packageName) {
-        logWtf(message, null);
-        // uptime is monotonic even after a framework restart
-        final long uptime = SystemClock.elapsedRealtime();
-        final long now = System.currentTimeMillis();
-        final long minCrashIntervalMs = DeviceConfig.getLong(DeviceConfig.NAMESPACE_CONNECTIVITY,
-                CONFIG_MIN_CRASH_INTERVAL_MS, DEFAULT_MIN_CRASH_INTERVAL_MS);
-        final long minUptimeBeforeCrash = DeviceConfig.getLong(DeviceConfig.NAMESPACE_CONNECTIVITY,
-                CONFIG_MIN_UPTIME_BEFORE_CRASH_MS, DEFAULT_MIN_UPTIME_BEFORE_CRASH_MS);
-        final boolean alwaysRatelimit = DeviceConfig.getBoolean(DeviceConfig.NAMESPACE_CONNECTIVITY,
-                CONFIG_ALWAYS_RATELIMIT_NETWORKSTACK_CRASH, false);
-
-        final SharedPreferences prefs = getSharedPreferences(context);
-        final long lastCrashTime = tryGetLastCrashTime(prefs);
-
-        // Only crash if there was enough time since boot, and (if known) enough time passed since
-        // the last crash.
-        // time and lastCrashTime may be unreliable if devices have incorrect clock time, but they
-        // are only used to limit the number of crashes compared to only using the time since boot,
-        // which would also be OK behavior by itself.
-        // - If lastCrashTime is incorrectly more than the current time, only look at uptime
-        // - If it is much less than current time, only look at uptime
-        // - If current time is during the next few hours after last crash time, don't crash.
-        //   Considering that this only matters if last boot was some time ago, it's likely that
-        //   time will be set correctly. Otherwise, not crashing is not a big problem anyway. Being
-        //   in this last state would also not last for long since the window is only a few hours.
-        final boolean alwaysCrash = Build.IS_DEBUGGABLE && !alwaysRatelimit;
-        final boolean justBooted = uptime < minUptimeBeforeCrash;
-        final boolean haveLastCrashTime = (lastCrashTime != 0) && (lastCrashTime < now);
-        final boolean haveKnownRecentCrash =
-                haveLastCrashTime && (now < lastCrashTime + minCrashIntervalMs);
-        if (alwaysCrash || (!justBooted && !haveKnownRecentCrash)) {
-            // The system is not bound to its network stack (for example due to a crash in the
-            // network stack process): better crash rather than stay in a bad state where all
-            // networking is broken.
-            // Using device-encrypted SharedPreferences as DeviceConfig does not have a synchronous
-            // API to persist settings before a crash.
-            tryWriteLastCrashTime(prefs, now);
-            throw new IllegalStateException(message);
-        }
-
-        // Here the system crashed recently already. Inform listeners that something is
-        // definitely wrong.
-        if (packageName != null) {
-            final ArraySet<NetworkStackHealthListener> listeners;
-            synchronized (mHealthListeners) {
-                listeners = new ArraySet<>(mHealthListeners);
-            }
-            for (NetworkStackHealthListener listener : listeners) {
-                listener.onNetworkStackFailure(packageName);
-            }
-        }
-    }
-
-    @Nullable
-    private SharedPreferences getSharedPreferences(@NonNull Context context) {
-        try {
-            final File prefsFile = new File(
-                    Environment.getDataSystemDeDirectory(UserHandle.USER_SYSTEM), PREFS_FILE);
-            return context.createDeviceProtectedStorageContext()
-                    .getSharedPreferences(prefsFile, Context.MODE_PRIVATE);
-        } catch (Throwable e) {
-            logWtf("Error loading shared preferences", e);
-            return null;
-        }
-    }
-
-    private long tryGetLastCrashTime(@Nullable SharedPreferences prefs) {
-        if (prefs == null) return 0L;
-        try {
-            return prefs.getLong(PREF_KEY_LAST_CRASH_TIME, 0L);
-        } catch (Throwable e) {
-            logWtf("Error getting last crash time", e);
-            return 0L;
-        }
-    }
-
-    private void tryWriteLastCrashTime(@Nullable SharedPreferences prefs, long value) {
-        if (prefs == null) return;
-        try {
-            prefs.edit().putLong(PREF_KEY_LAST_CRASH_TIME, value).commit();
-        } catch (Throwable e) {
-            logWtf("Error writing last crash time", e);
-        }
-    }
-
     /**
      * Log a message in the local log.
      */
@@ -524,6 +291,8 @@ public class NetworkStackClient {
     public void dump(PrintWriter pw) {
         // dump is thread-safe on SharedLog
         mLog.dump(null, pw, null);
+        // dump connectivity module connector logs.
+        ConnectivityModuleConnector.getInstance().dump(pw);
 
         final int requestsQueueLength;
         synchronized (mPendingNetStackRequests) {