Merge "NetworkStackClient: Refactor network stack process interaction" (049c9b40) · Commits · e / os / android_frameworks_base

services/java/com/android/server/SystemServer.java

+10 −1

Original line number	Diff line number	Diff line
		@@ -37,6 +37,7 @@ import android.content.res.Resources.Theme;
		import android.database.sqlite.SQLiteCompatibilityWalFlags;
		import android.database.sqlite.SQLiteGlobal;
		import android.hardware.display.DisplayManagerInternal;
		import android.net.ConnectivityModuleConnector;
		import android.net.NetworkStackClient;
		import android.os.BaseBundle;
		import android.os.Binder;
		@@ -1269,6 +1270,14 @@ public final class SystemServer {
		mSystemServiceManager.startService(CONTENT_SUGGESTIONS_SERVICE_CLASS);
		traceEnd();

		traceBeginAndSlog("InitConnectivityModuleConnector");
		try {
		ConnectivityModuleConnector.getInstance().init(context);
		} catch (Throwable e) {
		reportWtf("initializing ConnectivityModuleConnector", e);
		}
		traceEnd();

		traceBeginAndSlog("InitNetworkStackClient");
		try {
		NetworkStackClient.getInstance().init();
		@@ -2163,7 +2172,7 @@ public final class SystemServer {
		// ActivityManagerService.mSystemReady and ActivityManagerService.mProcessesReady
		// are set to true. Be careful if moving this to a different place in the
		// startup sequence.
		NetworkStackClient.getInstance().start(context);
		NetworkStackClient.getInstance().start();
		} catch (Throwable e) {
		reportWtf("starting Network Stack", e);
		}

services/net/java/android/net/ConnectivityModuleConnector.java

0 → 100644

+423 −0

Original line number	Diff line number	Diff line
		/*
		* 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.Settings;
		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);
		// Called DeviceConfig to minimize merge conflicts
		final DeviceConfigStub DeviceConfig = new DeviceConfigStub(mContext);
		// 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);
		}

		/**
		* Stub class to replicate DeviceConfig behavior with minimal merge conflicts.
		*/
		private class DeviceConfigStub {
		private final Context mContext;

		// Namespace is actually unused, but is here to replicate the final API.
		private static final String NAMESPACE_CONNECTIVITY = "connectivity";

		private DeviceConfigStub(Context context) {
		mContext = context;
		}

		private long getLong(
		@NonNull String namespace, @NonNull String key, long defaultVal) {
		// Temporary solution until DeviceConfig is available
		try {
		return Settings.Global.getLong(
		mContext.getContentResolver(), TAG + "_" + key, defaultVal);
		} catch (Throwable e) {
		logWtf("Could not obtain setting " + key, e);
		return defaultVal;
		}
		}

		private boolean getBoolean(
		@NonNull String namespace, @NonNull String key, boolean defaultVal) {
		// Temporary solution until DeviceConfig is available
		return getLong(namespace, key, defaultVal ? 1 : 0) != 0;
		}
		}
		}

services/net/java/android/net/NetworkStackClient.java

+10 −274

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