Version bump

Signed-off-by: Jason A. Donenfeld <Jason@zx2c4.com>

.idea/inspectionProfiles/Default.xml

@@ -150,7 +150,6 @@
     <inspection_tool class="FieldMayBeFinal" enabled="true" level="WARNING" enabled_by_default="true" />
     <inspection_tool class="FieldMayBeStatic" enabled="true" level="WARNING" enabled_by_default="true" />
     <inspection_tool class="FieldMustBeInitialized" enabled="true" level="ERROR" enabled_by_default="true" />
-    <inspection_tool class="FieldNotUsedInToString" enabled="true" level="WARNING" enabled_by_default="true" />
     <inspection_tool class="FinalMethodInFinalClass" enabled="true" level="WARNING" enabled_by_default="true" />
     <inspection_tool class="FloatingPointEquality" enabled="true" level="WARNING" enabled_by_default="true" />
     <inspection_tool class="ForLoopReplaceableByWhile" enabled="true" level="WARNING" enabled_by_default="true">

app/build.gradle

@@ -5,21 +5,19 @@ apply plugin: 'com.android.application'
 final def keystorePropertiesFile = rootProject.file("keystore.properties")
 
 android {
-    buildToolsVersion '27.0.3'
+    buildToolsVersion '28.0.0'
     compileOptions {
         sourceCompatibility JavaVersion.VERSION_1_8
         targetCompatibility JavaVersion.VERSION_1_8
     }
     compileSdkVersion 27
-    dataBinding {
-        enabled true
-    }
+    dataBinding.enabled true
     defaultConfig {
         applicationId 'com.wireguard.android'
         minSdkVersion 21
         targetSdkVersion 27
-        versionCode 424
-        versionName '0.0.20180612'
+        versionCode 427
+        versionName '0.0.20180625'
     }
     // If the keystore file exists
     if (keystorePropertiesFile.exists()) {
@@ -49,8 +47,9 @@ android {
         }
     }
 }
+
 ext {
-    databindingVersion = '3.1.2'
+    databindingVersion = '3.1.3'
     supportLibsVersion = '27.1.1'
     streamsupportVersion = '1.6.0'
 }

app/src/main/java/com/wireguard/android/Application.java

@@ -24,6 +24,8 @@ import com.wireguard.android.util.ToolsInstaller;
 
 import java.io.File;
 import java.lang.ref.WeakReference;
+import java.util.ArrayList;
+import java.util.List;
 import java.util.concurrent.Executor;
 
 public class Application extends android.app.Application {
@@ -34,6 +36,10 @@ public class Application extends android.app.Application {
     private SharedPreferences sharedPreferences;
     private ToolsInstaller toolsInstaller;
     private TunnelManager tunnelManager;
+    private Handler handler;
+    private List<BackendCallback> haveBackendCallbacks = new ArrayList<>();
+    private final Object haveBackendCallbacksLock = new Object();
+
     public Application() {
         weakSelf = new WeakReference<>(this);
     }
@@ -47,11 +53,40 @@ public class Application extends android.app.Application {
     }
 
     public static Backend getBackend() {
-        return get().backend;
+        final Application app = get();
+        synchronized (app) {
+            if (app.backend == null) {
+                if (new File("/sys/module/wireguard").exists()) {
+                    try {
+                        app.rootShell.start();
+                        app.backend = new WgQuickBackend(app.getApplicationContext());
+                    } catch (final Exception ignored) { }
+                }
+                if (app.backend == null)
+                    app.backend = new GoBackend(app.getApplicationContext());
+                synchronized (app.haveBackendCallbacksLock) {
+                    for (final BackendCallback callback : app.haveBackendCallbacks)
+                        app.handler.post(() -> callback.callback(app.backend));
+                    app.haveBackendCallbacks = null;
+                }
+            }
+            return app.backend;
+        }
     }
 
-    public static Class getBackendType() {
-        return get().backend.getClass();
+    @FunctionalInterface
+    public interface BackendCallback {
+        void callback(final Backend backend);
+    }
+
+    public static void onHaveBackend(final BackendCallback callback) {
+        final Application app = get();
+        synchronized (app.haveBackendCallbacksLock) {
+            if (app.haveBackendCallbacks == null)
+                callback.callback(app.backend);
+            else
+                app.haveBackendCallbacks.add(callback);
+        }
     }
 
     public static RootShell getRootShell() {
@@ -74,8 +109,8 @@ public class Application extends android.app.Application {
     public void onCreate() {
         super.onCreate();
 
+        handler = new Handler(Looper.getMainLooper());
         final Executor executor = AsyncTask.SERIAL_EXECUTOR;
-        final Handler handler = new Handler(Looper.getMainLooper());
         final ConfigStore configStore = new FileConfigStore(getApplicationContext());
 
         asyncWorker = new AsyncWorker(executor, handler);
@@ -87,16 +122,8 @@ public class Application extends android.app.Application {
                 sharedPreferences.getBoolean("dark_theme", false) ?
                         AppCompatDelegate.MODE_NIGHT_YES : AppCompatDelegate.MODE_NIGHT_NO);
 
-        if (new File("/sys/module/wireguard").exists()) {
-            try {
-                rootShell.start();
-                backend = new WgQuickBackend(getApplicationContext());
-            } catch (final Exception ignored) { }
-        }
-        if (backend == null)
-            backend = new GoBackend(getApplicationContext());
-
-        tunnelManager = new TunnelManager(backend, configStore);
+        tunnelManager = new TunnelManager(configStore);
+        asyncWorker.runAsync(Application::getBackend);
         tunnelManager.onCreate();
     }
 }

app/src/main/java/com/wireguard/android/BootShutdownReceiver.java

@@ -20,18 +20,20 @@ public class BootShutdownReceiver extends BroadcastReceiver {
 
     @Override
     public void onReceive(final Context context, final Intent intent) {
-        if (Application.getBackendType() != WgQuickBackend.class)
-            return;
-        final String action = intent.getAction();
-        if (action == null)
-            return;
-        final TunnelManager tunnelManager = Application.getTunnelManager();
-        if (Intent.ACTION_BOOT_COMPLETED.equals(action)) {
-            Log.i(TAG, "Broadcast receiver restoring state (boot)");
-            tunnelManager.restoreState(false).whenComplete(ExceptionLoggers.D);
-        } else if (Intent.ACTION_SHUTDOWN.equals(action)) {
-            Log.i(TAG, "Broadcast receiver saving state (shutdown)");
-            tunnelManager.saveState();
-        }
+        Application.onHaveBackend(backend -> {
+            if (backend.getClass() != WgQuickBackend.class)
+                return;
+            final String action = intent.getAction();
+            if (action == null)
+                return;
+            final TunnelManager tunnelManager = Application.getTunnelManager();
+            if (Intent.ACTION_BOOT_COMPLETED.equals(action)) {
+                Log.i(TAG, "Broadcast receiver restoring state (boot)");
+                tunnelManager.restoreState(false).whenComplete(ExceptionLoggers.D);
+            } else if (Intent.ACTION_SHUTDOWN.equals(action)) {
+                Log.i(TAG, "Broadcast receiver saving state (shutdown)");
+                tunnelManager.saveState();
+            }
+        });
     }
 }

app/src/main/java/com/wireguard/android/QuickTileService.java

@@ -20,7 +20,6 @@ import android.widget.Toast;
 import com.wireguard.android.activity.MainActivity;
 import com.wireguard.android.model.Tunnel;
 import com.wireguard.android.model.Tunnel.State;
-import com.wireguard.android.model.TunnelManager;
 import com.wireguard.android.util.ExceptionLoggers;
 
 import java.util.Objects;
@@ -50,11 +49,6 @@ public class QuickTileService extends TileService {
         }
     }
 
-    @Override
-    public void onCreate() {
-        super.onCreate();
-    }
-
     @Override
     public void onStartListening() {
         Application.getTunnelManager().addOnPropertyChangedCallback(onTunnelChangedCallback);

app/src/main/java/com/wireguard/android/activity/BaseActivity.java

@@ -10,7 +10,6 @@ import android.content.Intent;
 import android.databinding.CallbackRegistry;
 import android.databinding.CallbackRegistry.NotifierCallback;
 import android.os.Bundle;
-import android.support.v7.app.AppCompatActivity;
 
 import com.wireguard.android.Application;
 import com.wireguard.android.backend.GoBackend;
@@ -54,11 +53,13 @@ public abstract class BaseActivity extends ThemeChangeAwareActivity {
         // The selected tunnel must be set before the superclass method recreates fragments.
         super.onCreate(savedInstanceState);
 
-        if (Application.getBackendType() == GoBackend.class) {
-            final Intent intent = GoBackend.VpnService.prepare(this);
-            if (intent != null)
-                startActivityForResult(intent, 0);
-        }
+        Application.onHaveBackend(backend -> {
+            if (backend.getClass() == GoBackend.class) {
+                final Intent intent = GoBackend.VpnService.prepare(this);
+                if (intent != null)
+                    startActivityForResult(intent, 0);
+            }
+        });
     }
 
     @Override

app/src/main/java/com/wireguard/android/activity/SettingsActivity.java

@@ -6,16 +6,14 @@
 
 package com.wireguard.android.activity;
 
-import android.content.SharedPreferences;
 import android.content.pm.PackageManager;
 import android.os.Bundle;
 import android.support.annotation.NonNull;
 import android.support.v4.app.ActivityCompat;
 import android.support.v4.content.ContextCompat;
-import android.support.v7.app.AppCompatActivity;
-import android.support.v7.app.AppCompatDelegate;
 import android.support.v7.preference.Preference;
 import android.support.v7.preference.PreferenceFragmentCompat;
+import android.support.v7.preference.PreferenceScreen;
 import android.view.MenuItem;
 
 import com.wireguard.android.Application;
@@ -95,12 +93,21 @@ public class SettingsActivity extends ThemeChangeAwareActivity {
         @Override
         public void onCreatePreferences(final Bundle savedInstanceState, final String key) {
             addPreferencesFromResource(R.xml.preferences);
-            if (Application.getBackendType() != WgQuickBackend.class) {
-                Preference pref = getPreferenceManager().findPreference("tools_installer");
-                getPreferenceScreen().removePreference(pref);
-                pref = getPreferenceManager().findPreference("restore_on_boot");
-                getPreferenceScreen().removePreference(pref);
-            }
+            final Preference wgQuickOnlyPrefs[] = {
+                getPreferenceManager().findPreference("tools_installer"),
+                getPreferenceManager().findPreference("restore_on_boot")
+            };
+            for (final Preference pref : wgQuickOnlyPrefs)
+                pref.setVisible(false);
+            final PreferenceScreen screen = getPreferenceScreen();
+            Application.onHaveBackend(backend -> {
+                for (final Preference pref : wgQuickOnlyPrefs) {
+                    if (backend.getClass() == WgQuickBackend.class)
+                        pref.setVisible(true);
+                    else
+                        screen.removePreference(pref);
+                }
+            });
         }
     }
 }

app/src/main/java/com/wireguard/android/backend/GoBackend.java

@@ -21,7 +21,7 @@ import com.wireguard.android.model.Tunnel.Statistics;
 import com.wireguard.android.util.ExceptionLoggers;
 import com.wireguard.android.util.SharedLibraryLoader;
 import com.wireguard.config.Config;
-import com.wireguard.config.IPCidr;
+import com.wireguard.config.InetNetwork;
 import com.wireguard.config.Interface;
 import com.wireguard.config.Peer;
 import com.wireguard.crypto.KeyEncoding;
@@ -156,7 +156,7 @@ public final class GoBackend implements Backend {
                         fmt.format("endpoint=%s\n", peer.getResolvedEndpointString());
                     if (peer.getPersistentKeepalive() != 0)
                         fmt.format("persistent_keepalive_interval=%d\n", peer.getPersistentKeepalive());
-                    for (final IPCidr addr : peer.getAllowedIPs()) {
+                    for (final InetNetwork addr : peer.getAllowedIPs()) {
                         fmt.format("allowed_ip=%s\n", addr.toString());
                     }
                 }
@@ -171,15 +171,15 @@ public final class GoBackend implements Backend {
             configureIntent.addFlags(Intent.FLAG_ACTIVITY_NEW_TASK);
             builder.setConfigureIntent(PendingIntent.getActivity(context, 0, configureIntent, 0));
 
-            for (final IPCidr addr : config.getInterface().getAddresses())
-                builder.addAddress(addr.getAddress(), addr.getCidr());
+            for (final InetNetwork addr : config.getInterface().getAddresses())
+                builder.addAddress(addr.getAddress(), addr.getMask());
 
             for (final InetAddress addr : config.getInterface().getDnses())
                 builder.addDnsServer(addr.getHostAddress());
 
             for (final Peer peer : config.getPeers()) {
-                for (final IPCidr addr : peer.getAllowedIPs())
-                    builder.addRoute(addr.getAddress(), addr.getCidr());
+                for (final InetNetwork addr : peer.getAllowedIPs())
+                    builder.addRoute(addr.getAddress(), addr.getMask());
             }
 
             int mtu = config.getInterface().getMtu();

app/src/main/java/com/wireguard/android/databinding/BindingAdapters.java

@@ -15,7 +15,7 @@ import android.widget.ListView;
 import android.widget.TextView;
 
 import com.wireguard.android.R;
-import com.wireguard.android.util.Keyed;
+import com.wireguard.util.Keyed;
 import com.wireguard.android.util.ObservableKeyedList;
 import com.wireguard.android.widget.ToggleSwitch;
 import com.wireguard.android.widget.ToggleSwitch.OnBeforeCheckedChangeListener;

app/src/main/java/com/wireguard/android/databinding/ObservableKeyedListAdapter.java

@@ -16,7 +16,7 @@ import android.view.ViewGroup;
 import android.widget.BaseAdapter;
 
 import com.wireguard.android.BR;
-import com.wireguard.android.util.Keyed;
+import com.wireguard.util.Keyed;
 import com.wireguard.android.util.ObservableKeyedList;
 
 import java.lang.ref.WeakReference;

app/src/main/java/com/wireguard/android/fragment/TunnelListFragment.java

@@ -38,8 +38,6 @@ import com.wireguard.android.R;
 import com.wireguard.android.activity.TunnelCreatorActivity;
 import com.wireguard.android.databinding.TunnelListFragmentBinding;
 import com.wireguard.android.model.Tunnel;
-import com.wireguard.android.model.TunnelManager;
-import com.wireguard.android.util.AsyncWorker;
 import com.wireguard.android.util.ExceptionLoggers;
 import com.wireguard.config.Config;
 

app/src/main/java/com/wireguard/android/model/Tunnel.java

@@ -13,7 +13,7 @@ import android.support.annotation.Nullable;
 
 import com.wireguard.android.BR;
 import com.wireguard.android.util.ExceptionLoggers;
-import com.wireguard.android.util.Keyed;
+import com.wireguard.util.Keyed;
 import com.wireguard.config.Config;
 
 import java.util.regex.Pattern;

app/src/main/java/com/wireguard/android/model/TunnelManager.java

@@ -15,7 +15,6 @@ import android.support.annotation.NonNull;
 
 import com.wireguard.android.Application;
 import com.wireguard.android.BR;
-import com.wireguard.android.backend.Backend;
 import com.wireguard.android.configStore.ConfigStore;
 import com.wireguard.android.model.Tunnel.State;
 import com.wireguard.android.model.Tunnel.Statistics;
@@ -47,7 +46,6 @@ public final class TunnelManager extends BaseObservable {
     private static final String KEY_RESTORE_ON_BOOT = "restore_on_boot";
     private static final String KEY_RUNNING_TUNNELS = "enabled_configs";
 
-    private final Backend backend;
     private final ConfigStore configStore;
     private final ObservableSortedKeyedList<String, Tunnel> tunnels =
             new ObservableSortedKeyedArrayList<>(COMPARATOR);
@@ -55,8 +53,7 @@ public final class TunnelManager extends BaseObservable {
     private boolean haveLoaded;
     private final ArrayList<CompletableFuture<Void>> delayedLoadRestoreTunnels = new ArrayList<>();
 
-    public TunnelManager(final Backend backend, final ConfigStore configStore) {
-        this.backend = backend;
+    public TunnelManager(final ConfigStore configStore) {
         this.configStore = configStore;
     }
 
@@ -86,12 +83,12 @@ public final class TunnelManager extends BaseObservable {
         tunnels.remove(tunnel);
         return Application.getAsyncWorker().runAsync(() -> {
             if (originalState == State.UP)
-                backend.setState(tunnel, State.DOWN);
+                Application.getBackend().setState(tunnel, State.DOWN);
             try {
                 configStore.delete(tunnel.getName());
             } catch (final Exception e) {
                 if (originalState == State.UP)
-                    backend.setState(tunnel, State.UP);
+                    Application.getBackend().setState(tunnel, State.UP);
                 // Re-throw the exception to fail the completion.
                 throw e;
             }
@@ -116,12 +113,12 @@ public final class TunnelManager extends BaseObservable {
     }
 
     CompletionStage<State> getTunnelState(final Tunnel tunnel) {
-        return Application.getAsyncWorker().supplyAsync(() -> backend.getState(tunnel))
+        return Application.getAsyncWorker().supplyAsync(() -> Application.getBackend().getState(tunnel))
                 .thenApply(tunnel::onStateChanged);
     }
 
     CompletionStage<Statistics> getTunnelStatistics(final Tunnel tunnel) {
-        return Application.getAsyncWorker().supplyAsync(() -> backend.getStatistics(tunnel))
+        return Application.getAsyncWorker().supplyAsync(() -> Application.getBackend().getStatistics(tunnel))
                 .thenApply(tunnel::onStatisticsChanged);
     }
 
@@ -131,7 +128,7 @@ public final class TunnelManager extends BaseObservable {
 
     public void onCreate() {
         Application.getAsyncWorker().supplyAsync(configStore::enumerate)
-                .thenAcceptBoth(Application.getAsyncWorker().supplyAsync(backend::enumerate), this::onTunnelsLoaded)
+                .thenAcceptBoth(Application.getAsyncWorker().supplyAsync(() -> Application.getBackend().enumerate()), this::onTunnelsLoaded)
                 .whenComplete(ExceptionLoggers.E);
     }
 
@@ -159,7 +156,7 @@ public final class TunnelManager extends BaseObservable {
     }
 
     public void refreshTunnelStates() {
-        Application.getAsyncWorker().supplyAsync(backend::enumerate)
+        Application.getAsyncWorker().supplyAsync(() -> Application.getBackend().enumerate())
                 .thenAccept(running -> {
                     for (final Tunnel tunnel : tunnels)
                         tunnel.onStateChanged(running.contains(tunnel.getName()) ? State.UP : State.DOWN);
@@ -207,7 +204,7 @@ public final class TunnelManager extends BaseObservable {
 
     CompletionStage<Config> setTunnelConfig(final Tunnel tunnel, final Config config) {
         return Application.getAsyncWorker().supplyAsync(() -> {
-            final Config appliedConfig = backend.applyConfig(tunnel, config);
+            final Config appliedConfig = Application.getBackend().applyConfig(tunnel, config);
             return configStore.save(tunnel.getName(), appliedConfig);
         }).thenApply(tunnel::onConfigChanged);
     }
@@ -227,11 +224,11 @@ public final class TunnelManager extends BaseObservable {
         tunnels.remove(tunnel);
         return Application.getAsyncWorker().supplyAsync(() -> {
             if (originalState == State.UP)
-                backend.setState(tunnel, State.DOWN);
+                Application.getBackend().setState(tunnel, State.DOWN);
             configStore.rename(tunnel.getName(), name);
             final String newName = tunnel.onNameChanged(name);
             if (originalState == State.UP)
-                backend.setState(tunnel, State.UP);
+                Application.getBackend().setState(tunnel, State.UP);
             return newName;
         }).whenComplete((newName, e) -> {
             // On failure, we don't know what state the tunnel might be in. Fix that.
@@ -247,7 +244,7 @@ public final class TunnelManager extends BaseObservable {
     CompletionStage<State> setTunnelState(final Tunnel tunnel, final State state) {
         // Ensure the configuration is loaded before trying to use it.
         return tunnel.getConfigAsync().thenCompose(x ->
-                Application.getAsyncWorker().supplyAsync(() -> backend.setState(tunnel, state))
+                Application.getAsyncWorker().supplyAsync(() -> Application.getBackend().setState(tunnel, state))
         ).whenComplete((newState, e) -> {
             // Ensure onStateChanged is always called (failure or not), and with the correct state.
             tunnel.onStateChanged(e == null ? newState : tunnel.getState());

app/src/main/java/com/wireguard/android/preference/LogExporterPreference.java

@@ -14,12 +14,11 @@ import android.support.design.widget.Snackbar;
 import android.support.v7.preference.Preference;
 import android.util.AttributeSet;
 import android.util.Log;
-import android.view.ContextThemeWrapper;
 
 import com.wireguard.android.Application;
 import com.wireguard.android.R;
-import com.wireguard.android.activity.SettingsActivity;
 import com.wireguard.android.util.ExceptionLoggers;
+import com.wireguard.android.util.FragmentUtils;
 
 import java.io.BufferedReader;
 import java.io.File;
@@ -40,16 +39,6 @@ public class LogExporterPreference extends Preference {
         super(context, attrs);
     }
 
-    private static SettingsActivity getPrefActivity(final Preference preference) {
-        final Context context = preference.getContext();
-        if (context instanceof ContextThemeWrapper) {
-            if (((ContextThemeWrapper) context).getBaseContext() instanceof SettingsActivity) {
-                return ((SettingsActivity) ((ContextThemeWrapper) context).getBaseContext());
-            }
-        }
-        return null;
-    }
-
     private void exportLog() {
         Application.getAsyncWorker().supplyAsync(() -> {
             final File path = Environment.getExternalStoragePublicDirectory(Environment.DIRECTORY_DOWNLOADS);
@@ -90,7 +79,7 @@ public class LogExporterPreference extends Preference {
             final String message = getContext().getString(R.string.log_export_error, error);
             Log.e(TAG, message, throwable);
             Snackbar.make(
-                    getPrefActivity(this).findViewById(android.R.id.content),
+                    FragmentUtils.getPrefActivity(this).findViewById(android.R.id.content),
                     message, Snackbar.LENGTH_LONG).show();
             setEnabled(true);
         } else {
@@ -113,7 +102,7 @@ public class LogExporterPreference extends Preference {
 
     @Override
     protected void onClick() {
-        getPrefActivity(this).ensurePermissions(
+        FragmentUtils.getPrefActivity(this).ensurePermissions(
                 new String[]{Manifest.permission.WRITE_EXTERNAL_STORAGE},
                 (permissions, granted) -> {
                     if (granted.length > 0 && granted[0] == PackageManager.PERMISSION_GRANTED) {

app/src/main/java/com/wireguard/android/preference/ToolsInstallerPreference.java

@@ -9,9 +9,7 @@ package com.wireguard.android.preference;
 import android.content.Context;
 import android.support.annotation.NonNull;
 import android.support.v7.preference.Preference;
-import android.system.OsConstants;
 import android.util.AttributeSet;
-import android.util.Log;
 
 import com.wireguard.android.Application;
 import com.wireguard.android.R;

app/src/main/java/com/wireguard/android/preference/VersionPreference.java

@@ -14,12 +14,6 @@ import android.util.AttributeSet;
 import com.wireguard.android.Application;
 import com.wireguard.android.BuildConfig;
 import com.wireguard.android.R;
-import com.wireguard.android.backend.Backend;
-import com.wireguard.android.backend.GoBackend;
-import com.wireguard.android.backend.WgQuickBackend;
-
-import java.util.ArrayList;
-import java.util.List;
 
 public class VersionPreference extends Preference {
     private String versionSummary;
@@ -27,13 +21,14 @@ public class VersionPreference extends Preference {
     public VersionPreference(final Context context, final AttributeSet attrs) {
         super(context, attrs);
 
-        final Backend backend = Application.getBackend();
-        versionSummary = getContext().getString(R.string.version_summary_checking, backend.getTypeName().toLowerCase());
-        Application.getAsyncWorker().supplyAsync(backend::getVersion).whenComplete((version, exception) -> {
-            versionSummary = exception == null
-                    ? getContext().getString(R.string.version_summary, backend.getTypeName(), version)
-                    : getContext().getString(R.string.version_summary_unknown, backend.getTypeName().toLowerCase());
-            notifyChanged();
+        Application.onHaveBackend(backend -> {
+            versionSummary = getContext().getString(R.string.version_summary_checking, backend.getTypeName().toLowerCase());
+            Application.getAsyncWorker().supplyAsync(backend::getVersion).whenComplete((version, exception) -> {
+                versionSummary = exception == null
+                        ? getContext().getString(R.string.version_summary, backend.getTypeName(), version)
+                        : getContext().getString(R.string.version_summary_unknown, backend.getTypeName().toLowerCase());
+                notifyChanged();
+            });
         });
     }
 

app/src/main/java/com/wireguard/android/preference/ZipExporterPreference.java

@@ -14,13 +14,12 @@ import android.support.design.widget.Snackbar;
 import android.support.v7.preference.Preference;
 import android.util.AttributeSet;
 import android.util.Log;
-import android.view.ContextThemeWrapper;
 
 import com.wireguard.android.Application;
 import com.wireguard.android.R;
-import com.wireguard.android.activity.SettingsActivity;
 import com.wireguard.android.model.Tunnel;
 import com.wireguard.android.util.ExceptionLoggers;
+import com.wireguard.android.util.FragmentUtils;
 import com.wireguard.config.Config;
 
 import java.io.File;
@@ -47,16 +46,6 @@ public class ZipExporterPreference extends Preference {
         super(context, attrs);
     }
 
-    private static SettingsActivity getPrefActivity(final Preference preference) {
-        final Context context = preference.getContext();
-        if (context instanceof ContextThemeWrapper) {
-            if (((ContextThemeWrapper) context).getBaseContext() instanceof SettingsActivity) {
-                return ((SettingsActivity) ((ContextThemeWrapper) context).getBaseContext());
-            }
-        }
-        return null;
-    }
-
     private void exportZip() {
         final List<Tunnel> tunnels = new ArrayList<>(Application.getTunnelManager().getTunnels());
         final List<CompletableFuture<Config>> futureConfigs = new ArrayList<>(tunnels.size());
@@ -96,7 +85,7 @@ public class ZipExporterPreference extends Preference {
             final String message = getContext().getString(R.string.zip_export_error, error);
             Log.e(TAG, message, throwable);
             Snackbar.make(
-                    getPrefActivity(this).findViewById(android.R.id.content),
+                    FragmentUtils.getPrefActivity(this).findViewById(android.R.id.content),
                     message, Snackbar.LENGTH_LONG).show();
             setEnabled(true);
         } else {
@@ -119,7 +108,7 @@ public class ZipExporterPreference extends Preference {
 
     @Override
     protected void onClick() {
-        getPrefActivity(this).ensurePermissions(
+        FragmentUtils.getPrefActivity(this).ensurePermissions(
                 new String[]{Manifest.permission.WRITE_EXTERNAL_STORAGE},
                 (permissions, granted) -> {
                     if (granted.length > 0 && granted[0] == PackageManager.PERMISSION_GRANTED) {

app/src/main/java/com/wireguard/android/util/FragmentUtils.java

@@ -0,0 +1,25 @@
+/*
+ * Copyright © 2018 Harsh Shandilya <msfjarvis@gmail.com>
+ * Copyright © 2018 Jason A. Donenfeld <Jason@zx2c4.com>. All Rights Reserved.
+ * SPDX-License-Identifier: GPL-2.0-or-later
+ */
+package com.wireguard.android.util;
+
+import android.content.Context;
+import android.support.v7.preference.Preference;
+import android.view.ContextThemeWrapper;
+
+import com.wireguard.android.activity.SettingsActivity;
+
+public class FragmentUtils {
+
+    public static SettingsActivity getPrefActivity(final Preference preference) {
+        final Context context = preference.getContext();
+        if (context instanceof ContextThemeWrapper) {
+            if (((ContextThemeWrapper) context).getBaseContext() instanceof SettingsActivity) {
+                return ((SettingsActivity) ((ContextThemeWrapper) context).getBaseContext());
+            }
+        }
+        return null;
+    }
+}

app/src/main/java/com/wireguard/android/util/ObservableKeyedArrayList.java

@@ -9,6 +9,8 @@ package com.wireguard.android.util;
 import android.databinding.ObservableArrayList;
 import android.support.annotation.NonNull;
 
+import com.wireguard.util.Keyed;
+
 import java.util.Collection;
 import java.util.ListIterator;
 import java.util.Objects;

app/src/main/java/com/wireguard/android/util/ObservableKeyedList.java

@@ -8,6 +8,9 @@ package com.wireguard.android.util;
 
 import android.databinding.ObservableList;
 
+import com.wireguard.util.Keyed;
+import com.wireguard.util.KeyedList;
+
 /**
  * A list that is both keyed and observable.
  */

app/src/main/java/com/wireguard/android/util/ObservableSortedKeyedArrayList.java

@@ -8,6 +8,9 @@ package com.wireguard.android.util;
 
 import android.support.annotation.NonNull;
 
+import com.wireguard.util.Keyed;
+import com.wireguard.util.SortedKeyedList;
+
 import java.util.AbstractList;
 import java.util.Collection;
 import java.util.Collections;

app/src/main/java/com/wireguard/android/util/ObservableSortedKeyedList.java

@@ -6,6 +6,9 @@
 
 package com.wireguard.android.util;
 
+import com.wireguard.util.Keyed;
+import com.wireguard.util.SortedKeyedList;
+
 /**
  * A list that is both sorted/keyed and observable.
  */

app/src/main/java/com/wireguard/android/util/SharedLibraryLoader.java

@@ -13,8 +13,8 @@ import java.io.File;
 import java.io.FileOutputStream;
 import java.io.IOException;
 import java.io.InputStream;
-import java.util.zip.ZipFile;
 import java.util.zip.ZipEntry;
+import java.util.zip.ZipFile;
 
 public final class SharedLibraryLoader {
     private static final String TAG = "WireGuard/" + SharedLibraryLoader.class.getSimpleName();
@@ -27,7 +27,7 @@ public final class SharedLibraryLoader {
         try {
             System.loadLibrary(libName);
             return;
-        } catch (UnsatisfiedLinkError e) {
+        } catch (final UnsatisfiedLinkError e) {
             Log.d(TAG, "Failed to load library normally, so attempting to extract from apk", e);
             noAbiException = e;
         }
@@ -59,7 +59,7 @@ public final class SharedLibraryLoader {
                 }
                 System.load(f.getAbsolutePath());
                 return;
-            } catch (Exception e) {
+            } catch (final Exception e) {
                 Log.d(TAG, "Failed to load library apk:/" + libZipPath, e);
                 noAbiException = e;
             } finally {

app/src/main/java/com/wireguard/android/widget/fab/FloatingActionButton.java

@@ -8,13 +8,26 @@ package com.wireguard.android.widget.fab;
 
 import android.content.Context;
 import android.content.res.TypedArray;
-import android.graphics.*;
+import android.graphics.Canvas;
+import android.graphics.Color;
+import android.graphics.LinearGradient;
+import android.graphics.Paint;
 import android.graphics.Paint.Style;
+import android.graphics.Rect;
+import android.graphics.Shader;
 import android.graphics.Shader.TileMode;
-import android.graphics.drawable.*;
+import android.graphics.drawable.ColorDrawable;
+import android.graphics.drawable.Drawable;
+import android.graphics.drawable.LayerDrawable;
+import android.graphics.drawable.ShapeDrawable;
 import android.graphics.drawable.ShapeDrawable.ShaderFactory;
+import android.graphics.drawable.StateListDrawable;
 import android.graphics.drawable.shapes.OvalShape;
-import android.support.annotation.*;
+import android.support.annotation.ColorRes;
+import android.support.annotation.DimenRes;
+import android.support.annotation.DrawableRes;
+import android.support.annotation.IntDef;
+import android.support.annotation.NonNull;
 import android.support.v4.content.ContextCompat;
 import android.support.v7.widget.AppCompatImageButton;
 import android.util.AttributeSet;

app/src/main/java/com/wireguard/android/widget/fab/FloatingActionsMenu.java

@@ -466,7 +466,7 @@ public class FloatingActionsMenu extends ViewGroup {
     }
 
     @Override
-    public void setEnabled(boolean enabled) {
+    public void setEnabled(final boolean enabled) {
         super.setEnabled(enabled);
 
         mAddButton.setEnabled(enabled);

app/src/main/java/com/wireguard/android/widget/fab/TouchDelegateGroup.java

@@ -13,11 +13,11 @@ import android.view.TouchDelegate;
 import android.view.View;
 
 import java.util.ArrayList;
-import java.util.List;
+import java.util.Collection;
 
 public class TouchDelegateGroup extends TouchDelegate {
     private static final Rect USELESS_HACKY_RECT = new Rect();
-    private final List<TouchDelegate> mTouchDelegates = new ArrayList<>();
+    private final Collection<TouchDelegate> mTouchDelegates = new ArrayList<>();
     private TouchDelegate mCurrentTouchDelegate;
     private boolean mEnabled;
 
@@ -49,8 +49,7 @@ public class TouchDelegateGroup extends TouchDelegate {
 
         switch (event.getAction()) {
             case MotionEvent.ACTION_DOWN:
-                for (int i = 0; i < mTouchDelegates.size(); i++) {
-                    final TouchDelegate touchDelegate = mTouchDelegates.get(i);
+		for (final TouchDelegate touchDelegate : mTouchDelegates) {
                     if (touchDelegate.onTouchEvent(event)) {
                         mCurrentTouchDelegate = touchDelegate;
                         return true;

app/src/main/java/com/wireguard/config/Attribute.java

@@ -8,9 +8,6 @@ package com.wireguard.config;
 
 import android.text.TextUtils;
 
-import java.lang.reflect.InvocationTargetException;
-import java.lang.reflect.Method;
-import java.net.InetAddress;
 import java.util.HashMap;
 import java.util.Locale;
 import java.util.Map;
@@ -36,7 +33,6 @@ enum Attribute {
     private static final String[] EMPTY_LIST = new String[0];
     private static final Map<String, Attribute> KEY_MAP;
     private static final Pattern LIST_SEPARATOR_PATTERN = Pattern.compile("\\s*,\\s*");
-    private static final Method NUMERIC_ADDRESS_PARSER;
     private static final Pattern SEPARATOR_PATTERN = Pattern.compile("\\s|=");
 
     static {
@@ -46,14 +42,6 @@ enum Attribute {
         }
     }
 
-    static {
-        try {
-            NUMERIC_ADDRESS_PARSER = InetAddress.class.getMethod("parseNumericAddress", String.class);
-        } catch (final Exception e) {
-            throw new RuntimeException(e);
-        }
-    }
-
     private final Pattern pattern;
     private final String token;
 
@@ -70,21 +58,6 @@ enum Attribute {
         return KEY_MAP.get(SEPARATOR_PATTERN.split(line)[0].toLowerCase());
     }
 
-    public static InetAddress parseIPString(final String address) {
-        if (address == null || address.isEmpty())
-            throw new IllegalArgumentException("Empty address");
-        try {
-            return (InetAddress) NUMERIC_ADDRESS_PARSER.invoke(null, address);
-        } catch (final IllegalAccessException e) {
-            throw new RuntimeException(e);
-        } catch (final InvocationTargetException e) {
-            if (e.getCause() instanceof IllegalArgumentException)
-                throw (IllegalArgumentException) e.getCause();
-            else
-                throw new IllegalArgumentException(e.getCause());
-        }
-    }
-
     public static String[] stringToList(final String string) {
         if (string == null)
             return EMPTY_LIST;

app/src/main/java/com/wireguard/config/IPCidr.java

@@ -1,48 +0,0 @@
-/*
- * Copyright © 2018 Samuel Holland <samuel@sholland.org>
- * Copyright © 2018 Jason A. Donenfeld <Jason@zx2c4.com>. All Rights Reserved.
- * SPDX-License-Identifier: GPL-2.0-or-later
- */
-
-package com.wireguard.config;
-
-import java.net.Inet4Address;
-import java.net.Inet6Address;
-import java.net.InetAddress;
-import java.util.Locale;
-
-public class IPCidr {
-    private final InetAddress address;
-    private int cidr;
-
-    @SuppressWarnings("MagicNumber")
-    public IPCidr(String in) {
-        cidr = -1;
-        final int slash = in.lastIndexOf('/');
-        if (slash != -1 && slash < in.length() - 1) {
-            try {
-                cidr = Integer.parseInt(in.substring(slash + 1), 10);
-                in = in.substring(0, slash);
-            } catch (final Exception ignored) {
-            }
-        }
-        address = Attribute.parseIPString(in);
-        if ((address instanceof Inet6Address) && (cidr > 128 || cidr < 0))
-            cidr = 128;
-        else if ((address instanceof Inet4Address) && (cidr > 32 || cidr < 0))
-            cidr = 32;
-    }
-
-    public InetAddress getAddress() {
-        return address;
-    }
-
-    public int getCidr() {
-        return cidr;
-    }
-
-    @Override
-    public String toString() {
-        return String.format(Locale.getDefault(), "%s/%d", address.getHostAddress(), cidr);
-    }
-}

app/src/main/java/com/wireguard/config/InetAddresses.java

@@ -0,0 +1,42 @@
+/*
+ * Copyright © 2018 Samuel Holland <samuel@sholland.org>
+ * Copyright © 2018 Jason A. Donenfeld <Jason@zx2c4.com>. All Rights Reserved.
+ * SPDX-License-Identifier: GPL-2.0-or-later
+ */
+
+package com.wireguard.config;
+
+import android.support.annotation.NonNull;
+import android.support.annotation.Nullable;
+
+import java.lang.reflect.InvocationTargetException;
+import java.lang.reflect.Method;
+import java.net.InetAddress;
+
+public final class InetAddresses {
+    private static final Method PARSER_METHOD;
+
+    static {
+        try {
+            // This method is only present on Android.
+            PARSER_METHOD = InetAddress.class.getMethod("parseNumericAddress", String.class);
+        } catch (final NoSuchMethodException e) {
+            throw new RuntimeException(e);
+        }
+    }
+
+    private InetAddresses() {
+        // Prevent instantiation.
+    }
+
+    @NonNull
+    public static InetAddress parse(@Nullable final String address) {
+        if (address == null || address.isEmpty())
+            throw new IllegalArgumentException("Empty address");
+        try {
+            return (InetAddress) PARSER_METHOD.invoke(null, address);
+        } catch (final IllegalAccessException | InvocationTargetException e) {
+            throw new RuntimeException(e);
+        }
+    }
+}

app/src/main/java/com/wireguard/config/InetNetwork.java

@@ -0,0 +1,61 @@
+/*
+ * Copyright © 2018 Samuel Holland <samuel@sholland.org>
+ * Copyright © 2018 Jason A. Donenfeld <Jason@zx2c4.com>. All Rights Reserved.
+ * SPDX-License-Identifier: GPL-2.0-or-later
+ */
+
+package com.wireguard.config;
+
+import android.support.annotation.NonNull;
+
+import java.net.Inet4Address;
+import java.net.InetAddress;
+import java.util.Objects;
+
+public class InetNetwork {
+    private final InetAddress address;
+    private final int mask;
+
+    public InetNetwork(@NonNull final String input) {
+        final int slash = input.lastIndexOf('/');
+        final int rawMask;
+        final String rawAddress;
+        if (slash >= 0) {
+            rawMask = Integer.parseInt(input.substring(slash + 1), 10);
+            rawAddress = input.substring(0, slash);
+        } else {
+            rawMask = -1;
+            rawAddress = input;
+        }
+        address = InetAddresses.parse(rawAddress);
+        final int maxMask = (address instanceof Inet4Address) ? 32 : 128;
+        mask = rawMask >= 0 && rawMask <= maxMask ? rawMask : maxMask;
+    }
+
+    @Override
+    public boolean equals(final Object obj) {
+        if (!(obj instanceof InetNetwork))
+            return false;
+        final InetNetwork other = (InetNetwork) obj;
+        return Objects.equals(address, other.address) && mask == other.mask;
+    }
+
+    @NonNull
+    public InetAddress getAddress() {
+        return address;
+    }
+
+    public int getMask() {
+        return mask;
+    }
+
+    @Override
+    public int hashCode() {
+        return address.hashCode() ^ mask;
+    }
+
+    @Override
+    public String toString() {
+        return address.getHostAddress() + '/' + mask;
+    }
+}

app/src/main/java/com/wireguard/config/Interface.java

@@ -23,7 +23,7 @@ import java.util.List;
  */
 
 public class Interface {
-    private final List<IPCidr> addressList;
+    private final List<InetNetwork> addressList;
     private final List<InetAddress> dnsList;
     private Keypair keypair;
     private int listenPort;
@@ -39,7 +39,7 @@ public class Interface {
             for (final String addr : addresses) {
                 if (addr.isEmpty())
                     throw new IllegalArgumentException("Address is empty");
-                addressList.add(new IPCidr(addr));
+                addressList.add(new InetNetwork(addr));
             }
         }
     }
@@ -47,7 +47,7 @@ public class Interface {
     private void addDnses(final String[] dnses) {
         if (dnses != null && dnses.length > 0) {
             for (final String dns : dnses) {
-                dnsList.add(Attribute.parseIPString(dns));
+                dnsList.add(InetAddresses.parse(dns));
             }
         }
     }
@@ -58,8 +58,8 @@ public class Interface {
         return Attribute.iterableToString(addressList);
     }
 
-    public IPCidr[] getAddresses() {
-        return addressList.toArray(new IPCidr[addressList.size()]);
+    public InetNetwork[] getAddresses() {
+        return addressList.toArray(new InetNetwork[addressList.size()]);
     }
 
     private String getDnsString() {

app/src/main/java/com/wireguard/config/Peer.java

@@ -28,7 +28,7 @@ import java.util.Locale;
  */
 
 public class Peer {
-    private final List<IPCidr> allowedIPsList;
+    private final List<InetNetwork> allowedIPsList;
     private InetSocketAddress endpoint;
     private int persistentKeepalive;
     private String preSharedKey;
@@ -41,13 +41,13 @@ public class Peer {
     private void addAllowedIPs(final String[] allowedIPs) {
         if (allowedIPs != null && allowedIPs.length > 0) {
             for (final String allowedIP : allowedIPs) {
-                allowedIPsList.add(new IPCidr(allowedIP));
+                allowedIPsList.add(new InetNetwork(allowedIP));
             }
         }
     }
 
-    public IPCidr[] getAllowedIPs() {
-        return allowedIPsList.toArray(new IPCidr[allowedIPsList.size()]);
+    public InetNetwork[] getAllowedIPs() {
+        return allowedIPsList.toArray(new InetNetwork[allowedIPsList.size()]);
     }
 
     private String getAllowedIPsString() {

app/src/main/java/com/wireguard/crypto/Curve25519.java

@@ -10,23 +10,23 @@ import java.util.Arrays;
 /**
  * Implementation of the Curve25519 elliptic curve algorithm.
  * <p>
+ * This implementation was imported to WireGuard from noise-java:
+ * https://github.com/rweather/noise-java
+ * <p>
  * This implementation is based on that from arduinolibs:
  * https://github.com/rweather/arduinolibs
  * <p>
- * This implementation is copied verbatim from noise-java:
- * https://github.com/rweather/noise-java
- * <p>
  * Differences in this version are due to using 26-bit limbs for the
  * representation instead of the 8/16/32-bit limbs in the original.
  * <p>
  * References: http://cr.yp.to/ecdh.html, RFC 7748
  */
-@SuppressWarnings("MagicNumber")
+@SuppressWarnings({"MagicNumber", "NonConstantFieldWithUpperCaseName", "SuspiciousNameCombination"})
 public final class Curve25519 {
-
     // Numbers modulo 2^255 - 19 are broken up into ten 26-bit words.
     private static final int NUM_LIMBS_255BIT = 10;
     private static final int NUM_LIMBS_510BIT = 20;
+
     private final int[] A;
     private final int[] AA;
     private final int[] B;
@@ -152,6 +152,38 @@ public final class Curve25519 {
         }
     }
 
+    /**
+     * Subtracts two numbers modulo 2^255 - 19.
+     *
+     * @param result The result.
+     * @param x      The first number to subtract.
+     * @param y      The second number to subtract.
+     */
+    private static void sub(final int[] result, final int[] x, final int[] y) {
+        int index;
+        int borrow;
+
+        // Subtract y from x to generate the intermediate result.
+        borrow = 0;
+        for (index = 0; index < NUM_LIMBS_255BIT; ++index) {
+            borrow = x[index] - y[index] - ((borrow >> 26) & 0x01);
+            result[index] = borrow & 0x03FFFFFF;
+        }
+
+        // If we had a borrow, then the result has gone negative and we
+        // have to add 2^255 - 19 to the result to make it positive again.
+        // The top bits of "borrow" will be all 1's if there is a borrow
+        // or it will be all 0's if there was no borrow.  Easiest is to
+        // conditionally subtract 19 and then mask off the high bits.
+        borrow = result[0] - ((-((borrow >> 26) & 0x01)) & 19);
+        result[0] = borrow & 0x03FFFFFF;
+        for (index = 1; index < NUM_LIMBS_255BIT; ++index) {
+            borrow = result[index] - ((borrow >> 26) & 0x01);
+            result[index] = borrow & 0x03FFFFFF;
+        }
+        result[NUM_LIMBS_255BIT - 1] &= 0x001FFFFF;
+    }
+
     /**
      * Adds two numbers modulo 2^255 - 19.
      *
@@ -160,8 +192,7 @@ public final class Curve25519 {
      * @param y      The second number to add.
      */
     private void add(final int[] result, final int[] x, final int[] y) {
-        int carry;
-        carry = x[0] + y[0];
+        int carry = x[0] + y[0];
         result[0] = carry & 0x03FFFFFF;
         for (int index = 1; index < NUM_LIMBS_255BIT; ++index) {
             carry = (carry >> 26) + x[index] + y[index];
@@ -200,12 +231,13 @@ public final class Curve25519 {
      */
     private void evalCurve(final byte[] s) {
         int sposn = 31;
+        int sbit = 6;
         int svalue = s[sposn] | 0x40;
         int swap = 0;
 
         // Iterate over all 255 bits of "s" from the highest to the lowest.
         // We ignore the high bit of the 256-bit representation of "s".
-        for (int sbit = 6; ; ) {
+        while (true) {
             // Conditional swaps on entry to this bit but only if we
             // didn't swap on the previous bit.
             final int select = (svalue >> sbit) & 0x01;
@@ -263,14 +295,12 @@ public final class Curve25519 {
      * @param y      The second number to multiply.
      */
     private void mul(final int[] result, final int[] x, final int[] y) {
-        int i;
-
         // Multiply the two numbers to create the intermediate result.
         long v = x[0];
-        for (i = 0; i < NUM_LIMBS_255BIT; ++i) {
+        for (int i = 0; i < NUM_LIMBS_255BIT; ++i) {
             t1[i] = v * y[i];
         }
-        for (i = 1; i < NUM_LIMBS_255BIT; ++i) {
+        for (int i = 1; i < NUM_LIMBS_255BIT; ++i) {
             v = x[i];
             for (int j = 0; j < (NUM_LIMBS_255BIT - 1); ++j) {
                 t1[i + j] += v * y[j];
@@ -281,7 +311,7 @@ public final class Curve25519 {
         // Propagate carries and convert back into 26-bit words.
         v = t1[0];
         t2[0] = ((int) v) & 0x03FFFFFF;
-        for (i = 1; i < NUM_LIMBS_510BIT; ++i) {
+        for (int i = 1; i < NUM_LIMBS_510BIT; ++i) {
             v = (v >> 26) + t1[i];
             t2[i] = ((int) v) & 0x03FFFFFF;
         }
@@ -315,8 +345,6 @@ public final class Curve25519 {
      * @param x      The argument.
      */
     private void pow250(final int[] result, final int[] x) {
-        int j;
-
         // The big-endian hexadecimal expansion of (2^250 - 1) is:
         // 03FFFFFF FFFFFFFF FFFFFFFF FFFFFFFF FFFFFFFF FFFFFFFF FFFFFFFF FFFFFFFF
         //
@@ -329,11 +357,11 @@ public final class Curve25519 {
 
         // Build a pattern of 250 bits in length of repeated copies of 0000000001.
         square(A, x);
-        for (j = 0; j < 9; ++j)
+        for (int j = 0; j < 9; ++j)
             square(A, A);
         mul(result, A, x);
         for (int i = 0; i < 23; ++i) {
-            for (j = 0; j < 10; ++j)
+            for (int j = 0; j < 10; ++j)
                 square(A, A);
             mul(result, result, A);
         }
@@ -342,7 +370,7 @@ public final class Curve25519 {
         // the result to "fill in" the gaps in the pattern.
         square(A, result);
         mul(result, result, A);
-        for (j = 0; j < 8; ++j) {
+        for (int j = 0; j < 8; ++j) {
             square(A, A);
             mul(result, result, A);
         }
@@ -381,18 +409,14 @@ public final class Curve25519 {
      * @param size   The number of limbs in the high order half of x.
      */
     private void reduce(final int[] result, final int[] x, final int size) {
-        int index;
-        int limb;
-        int carry;
-
         // Calculate (x mod 2^255) + ((x / 2^255) * 19) which will
         // either produce the answer we want or it will produce a
         // value of the form "answer + j * (2^255 - 19)".  There are
         // 5 left-over bits in the top-most limb of the bottom half.
-        carry = 0;
-        limb = x[NUM_LIMBS_255BIT - 1] >> 21;
+        int carry = 0;
+        int limb = x[NUM_LIMBS_255BIT - 1] >> 21;
         x[NUM_LIMBS_255BIT - 1] &= 0x001FFFFF;
-        for (index = 0; index < size; ++index) {
+        for (int index = 0; index < size; ++index) {
             limb += x[NUM_LIMBS_255BIT + index] << 5;
             carry += (limb & 0x03FFFFFF) * 19 + x[index];
             x[index] = carry & 0x03FFFFFF;
@@ -402,7 +426,7 @@ public final class Curve25519 {
         if (size < NUM_LIMBS_255BIT) {
             // The high order half of the number is short; e.g. for mulA24().
             // Propagate the carry through the rest of the low order part.
-            for (index = size; index < NUM_LIMBS_255BIT; ++index) {
+            for (int index = size; index < NUM_LIMBS_255BIT; ++index) {
                 carry += x[index];
                 x[index] = carry & 0x03FFFFFF;
                 carry >>= 26;
@@ -417,7 +441,7 @@ public final class Curve25519 {
         // top 5 bits of the highest limb of the bottom half.
         carry = (x[NUM_LIMBS_255BIT - 1] >> 21) * 19;
         x[NUM_LIMBS_255BIT - 1] &= 0x001FFFFF;
-        for (index = 0; index < NUM_LIMBS_255BIT; ++index) {
+        for (int index = 0; index < NUM_LIMBS_255BIT; ++index) {
             carry += x[index];
             result[index] = carry & 0x03FFFFFF;
             carry >>= 26;
@@ -436,14 +460,11 @@ public final class Curve25519 {
      * @param x The number to reduce, and the result.
      */
     private void reduceQuick(final int[] x) {
-        int index;
-        int carry;
-
         // Perform a trial subtraction of (2^255 - 19) from "x" which is
         // equivalent to adding 19 and subtracting 2^255.  We add 19 here;
         // the subtraction of 2^255 occurs in the next step.
-        carry = 19;
-        for (index = 0; index < NUM_LIMBS_255BIT; ++index) {
+        int carry = 19;
+        for (int index = 0; index < NUM_LIMBS_255BIT; ++index) {
             carry += x[index];
             t2[index] = carry & 0x03FFFFFF;
             carry >>= 26;
@@ -457,7 +478,7 @@ public final class Curve25519 {
         final int mask = -((t2[NUM_LIMBS_255BIT - 1] >> 21) & 0x01);
         final int nmask = ~mask;
         t2[NUM_LIMBS_255BIT - 1] &= 0x001FFFFF;
-        for (index = 0; index < NUM_LIMBS_255BIT; ++index)
+        for (int index = 0; index < NUM_LIMBS_255BIT; ++index)
             x[index] = (x[index] & nmask) | (t2[index] & mask);
     }
 
@@ -470,36 +491,4 @@ public final class Curve25519 {
     private void square(final int[] result, final int[] x) {
         mul(result, x, x);
     }
-
-    /**
-     * Subtracts two numbers modulo 2^255 - 19.
-     *
-     * @param result The result.
-     * @param x      The first number to subtract.
-     * @param y      The second number to subtract.
-     */
-    private static void sub(final int[] result, final int[] x, final int[] y) {
-        int index;
-        int borrow;
-
-        // Subtract y from x to generate the intermediate result.
-        borrow = 0;
-        for (index = 0; index < NUM_LIMBS_255BIT; ++index) {
-            borrow = x[index] - y[index] - ((borrow >> 26) & 0x01);
-            result[index] = borrow & 0x03FFFFFF;
-        }
-
-        // If we had a borrow, then the result has gone negative and we
-        // have to add 2^255 - 19 to the result to make it positive again.
-        // The top bits of "borrow" will be all 1's if there is a borrow
-        // or it will be all 0's if there was no borrow.  Easiest is to
-        // conditionally subtract 19 and then mask off the high bits.
-        borrow = result[0] - ((-((borrow >> 26) & 0x01)) & 19);
-        result[0] = borrow & 0x03FFFFFF;
-        for (index = 1; index < NUM_LIMBS_255BIT; ++index) {
-            borrow = result[index] - ((borrow >> 26) & 0x01);
-            result[index] = borrow & 0x03FFFFFF;
-        }
-        result[NUM_LIMBS_255BIT - 1] &= 0x001FFFFF;
-    }
 }

app/src/main/java/com/wireguard/util/Keyed.java

@@ -1,10 +1,9 @@
 /*
  * Copyright © 2018 Samuel Holland <samuel@sholland.org>
- * Copyright © 2018 Jason A. Donenfeld <Jason@zx2c4.com>. All Rights Reserved.
  * SPDX-License-Identifier: GPL-2.0-or-later
  */
 
-package com.wireguard.android.util;
+package com.wireguard.util;
 
 /**
  * Interface for objects that have a identifying key of the given type.

app/src/main/java/com/wireguard/util/KeyedList.java

@@ -1,10 +1,9 @@
 /*
  * Copyright © 2018 Samuel Holland <samuel@sholland.org>
- * Copyright © 2018 Jason A. Donenfeld <Jason@zx2c4.com>. All Rights Reserved.
  * SPDX-License-Identifier: GPL-2.0-or-later
  */
 
-package com.wireguard.android.util;
+package com.wireguard.util;
 
 import java.util.Collection;
 import java.util.List;

app/src/main/java/com/wireguard/util/SortedKeyedList.java

@@ -1,10 +1,9 @@
 /*
  * Copyright © 2018 Samuel Holland <samuel@sholland.org>
- * Copyright © 2018 Jason A. Donenfeld <Jason@zx2c4.com>. All Rights Reserved.
  * SPDX-License-Identifier: GPL-2.0-or-later
  */
 
-package com.wireguard.android.util;
+package com.wireguard.util;
 
 import java.util.Collection;
 import java.util.Comparator;

build.gradle

@@ -7,7 +7,7 @@ allprojects {
 
 buildscript {
     dependencies {
-        classpath 'com.android.tools.build:gradle:3.1.2'
+        classpath 'com.android.tools.build:gradle:3.1.3'
     }
     repositories {
         google()

gradle/wrapper/gradle-wrapper.properties

@@ -1,5 +1,5 @@
 distributionBase=GRADLE_USER_HOME
 distributionPath=wrapper/dists
+distributionUrl=https\://services.gradle.org/distributions/gradle-4.4-bin.zip
 zipStoreBase=GRADLE_USER_HOME
 zipStorePath=wrapper/dists
-distributionUrl=https\://services.gradle.org/distributions/gradle-4.4-bin.zip