diff options
author | Remi NGUYEN VAN <reminv@google.com> | 2019-06-09 18:33:16 -0700 |
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committer | android-build-merger <android-build-merger@google.com> | 2019-06-09 18:33:16 -0700 |
commit | 67e55b4b7096b0b4d2ffdf45c08a7a7c685ff084 (patch) | |
tree | f8ed14c9c180fcea64dc9cabb1bf195ab33b7b2a | |
parent | e15f92e37f70a400fa6f36bf2cfd63470cd1ac15 (diff) | |
parent | 870c267b6c208403d9ebed100c04f47ec1e7cf04 (diff) | |
download | base-67e55b4b7096b0b4d2ffdf45c08a7a7c685ff084.tar.gz |
Merge changes I399d3e37,Ia3fdd80c,Iad90c7a4
am: 870c267b6c
Change-Id: I1df4d64ef2c56a1f8f7fb6b5dfd6de1eab2e157b
-rw-r--r-- | services/net/java/android/net/NetworkStackClient.java | 203 |
1 files changed, 190 insertions, 13 deletions
diff --git a/services/net/java/android/net/NetworkStackClient.java b/services/net/java/android/net/NetworkStackClient.java index 6b5842ff9065..cf52574e83e3 100644 --- a/services/net/java/android/net/NetworkStackClient.java +++ b/services/net/java/android/net/NetworkStackClient.java @@ -26,6 +26,7 @@ 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; @@ -33,15 +34,21 @@ 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.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; import java.util.ArrayList; @@ -54,6 +61,23 @@ public class NetworkStackClient { 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; @@ -67,12 +91,28 @@ public class NetworkStackClient { @GuardedBy("mLog") private final SharedLog mLog = new SharedLog(TAG); - private volatile boolean mNetworkStackStartRequested = false; + 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() { } /** @@ -86,6 +126,15 @@ 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. @@ -147,6 +196,16 @@ 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; + } + @Override public void onServiceConnected(ComponentName name, IBinder service) { logi("Network stack service connected"); @@ -155,14 +214,14 @@ public class NetworkStackClient { @Override public void onServiceDisconnected(ComponentName name) { - // The system has lost its network stack (probably due to a crash in the - // network stack process): better crash rather than stay in a bad state where all - // networking is broken. // onServiceDisconnected is not being called on device shutdown, so this method being // called always indicates a bad state for the system server. - maybeCrashWithTerribleFailure("Lost network stack"); + // 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) { final INetworkStackConnector connector = INetworkStackConnector.Stub.asInterface(service); @@ -189,7 +248,7 @@ public class NetworkStackClient { */ public void init() { log("Network stack init"); - mNetworkStackStartRequested = true; + mWasSystemServerInitialized = true; } /** @@ -202,6 +261,7 @@ public class NetworkStackClient { */ 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 @@ -216,16 +276,19 @@ public class NetworkStackClient { } if (intent == null) { - maybeCrashWithTerribleFailure("Could not resolve the network stack"); + 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(), + 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); + "Could not bind to network stack in-process, or in app with " + intent, + context, packageName); return; } @@ -274,11 +337,93 @@ public class NetworkStackClient { } } - private void maybeCrashWithTerribleFailure(@NonNull String message) { + private void maybeCrashWithTerribleFailure(@NonNull String message, + @NonNull Context context, @Nullable String packageName) { logWtf(message, null); - if (Build.IS_DEBUGGABLE) { + // Called DeviceConfig to minimize merge conflicts + final DeviceConfigStub DeviceConfig = new DeviceConfigStub(context); + // 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); + } } /** @@ -350,7 +495,7 @@ public class NetworkStackClient { "Only the system server should try to bind to the network stack."); } - if (!mNetworkStackStartRequested) { + if (!mWasSystemServerInitialized) { // The network stack is not being started in this process, e.g. this process is not // the system server. Get a remote connector registered by the system server. final INetworkStackConnector connector = getRemoteConnector(); @@ -388,4 +533,36 @@ public class NetworkStackClient { pw.println(); pw.println("pendingNetStackRequests length: " + requestsQueueLength); } + + /** + * 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; + } + } } |