global: format code

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

tunnel/src/main/java/com/wireguard/android/backend/BackendException.java

@@ -9,6 +9,21 @@ import com.wireguard.util.NonNullForAll;
 
 @NonNullForAll
 public final class BackendException extends Exception {
+    private final Object[] format;
+    private final Reason reason;
+    public BackendException(final Reason reason, final Object... format) {
+        this.reason = reason;
+        this.format = format;
+    }
+
+    public Object[] getFormat() {
+        return format;
+    }
+
+    public Reason getReason() {
+        return reason;
+    }
+
     public enum Reason {
         UNKNOWN_KERNEL_MODULE_NAME,
         WG_QUICK_CONFIG_ERROR_CODE,
@@ -18,16 +33,4 @@ public final class BackendException extends Exception {
         TUN_CREATION_ERROR,
         GO_ACTIVATION_ERROR_CODE
     }
-    private final Reason reason;
-    private final Object[] format;
-    public BackendException(final Reason reason, final Object ...format) {
-        this.reason = reason;
-        this.format = format;
-    }
-    public Reason getReason() {
-        return reason;
-    }
-    public Object[] getFormat() {
-        return format;
-    }
 }

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

@@ -34,25 +34,21 @@ import java9.util.concurrent.CompletableFuture;
 @NonNullForAll
 public final class GoBackend implements Backend {
     private static final String TAG = "WireGuard/" + GoBackend.class.getSimpleName();
-    private static CompletableFuture<VpnService> vpnService = new CompletableFuture<>();
-    public interface AlwaysOnCallback {
-        void alwaysOnTriggered();
-    }
     @Nullable private static AlwaysOnCallback alwaysOnCallback;
-    public static void setAlwaysOnCallback(AlwaysOnCallback cb) {
+    private static CompletableFuture<VpnService> vpnService = new CompletableFuture<>();
-        alwaysOnCallback = cb;
-    }
-
     private final Context context;
-    @Nullable private Tunnel currentTunnel;
     @Nullable private Config currentConfig;
+    @Nullable private Tunnel currentTunnel;
     private int currentTunnelHandle = -1;
-
     public GoBackend(final Context context) {
         SharedLibraryLoader.loadSharedLibrary(context, "wg-go");
         this.context = context;
     }
 
+    public static void setAlwaysOnCallback(AlwaysOnCallback cb) {
+        alwaysOnCallback = cb;
+    }
+
     private static native String wgGetConfig(int handle);
 
     private static native int wgGetSocketV4(int handle);
@@ -143,7 +139,7 @@ public final class GoBackend implements Backend {
                 setStateInternal(currentTunnel, null, State.DOWN);
             try {
                 setStateInternal(tunnel, config, state);
-            } catch(final Exception e) {
+            } catch (final Exception e) {
                 if (originalTunnel != null)
                     setStateInternal(originalTunnel, originalConfig, State.UP);
                 throw e;
@@ -209,7 +205,7 @@ public final class GoBackend implements Backend {
             if (Build.VERSION.SDK_INT >= Build.VERSION_CODES.Q)
                 builder.setMetered(false);
             if (Build.VERSION.SDK_INT >= Build.VERSION_CODES.M)
-	        service.setUnderlyingNetworks(null);
+                service.setUnderlyingNetworks(null);
 
             builder.setBlocking(true);
             try (final ParcelFileDescriptor tun = builder.establish()) {
@@ -246,13 +242,13 @@ public final class GoBackend implements Backend {
         context.startService(new Intent(context, VpnService.class));
     }
 
+    public interface AlwaysOnCallback {
+        void alwaysOnTriggered();
+    }
+
     public static class VpnService extends android.net.VpnService {
         @Nullable private GoBackend owner;
 
-        public void setOwner(final GoBackend owner) {
-            this.owner = owner;
-        }
-
         public Builder getBuilder() {
             return new Builder();
         }
@@ -290,5 +286,9 @@ public final class GoBackend implements Backend {
             }
             return super.onStartCommand(intent, flags, startId);
         }
+
+        public void setOwner(final GoBackend owner) {
+            this.owner = owner;
+        }
     }
 }

tunnel/src/main/java/com/wireguard/android/backend/Statistics.java

@@ -16,10 +16,11 @@ import java.util.Map;
 
 @NonNullForAll
 public class Statistics {
-    private long lastTouched = SystemClock.elapsedRealtime();
     private final Map<Key, Pair<Long, Long>> peerBytes = new HashMap<>();
+    private long lastTouched = SystemClock.elapsedRealtime();
 
-    Statistics() { }
+    Statistics() {
+    }
 
     void add(final Key key, final long rx, final long tx) {
         peerBytes.put(key, Pair.create(rx, tx));
@@ -30,10 +31,6 @@ public class Statistics {
         return SystemClock.elapsedRealtime() - lastTouched > 900;
     }
 
-    public Key[] peers() {
-        return peerBytes.keySet().toArray(new Key[0]);
-    }
-
     public long peerRx(final Key peer) {
         if (!peerBytes.containsKey(peer))
             return 0;
@@ -46,6 +43,10 @@ public class Statistics {
         return peerBytes.get(peer).second;
     }
 
+    public Key[] peers() {
+        return peerBytes.keySet().toArray(new Key[0]);
+    }
+
     public long totalRx() {
         long rx = 0;
         for (final Pair<Long, Long> val : peerBytes.values()) {

tunnel/src/main/java/com/wireguard/android/backend/Tunnel.java

@@ -15,16 +15,6 @@ import java.util.regex.Pattern;
 
 @NonNullForAll
 public interface Tunnel {
-    enum State {
-        DOWN,
-        TOGGLE,
-        UP;
-
-        public static State of(final boolean running) {
-            return running ? UP : DOWN;
-        }
-    }
-
     int NAME_MAX_LENGTH = 15;
     Pattern NAME_PATTERN = Pattern.compile("[a-zA-Z0-9_=+.-]{1,15}");
 
@@ -46,4 +36,14 @@ public interface Tunnel {
      * @return The new state of the tunnel.
      */
     void onStateChange(State newState);
+
+    enum State {
+        DOWN,
+        TOGGLE,
+        UP;
+
+        public static State of(final boolean running) {
+            return running ? UP : DOWN;
+        }
+    }
 }

tunnel/src/main/java/com/wireguard/android/backend/WgQuickBackend.java

@@ -42,11 +42,10 @@ import java9.util.stream.Stream;
 @NonNullForAll
 public final class WgQuickBackend implements Backend {
     private static final String TAG = "WireGuard/" + WgQuickBackend.class.getSimpleName();
-
-    private final RootShell rootShell;
-    private final ToolsInstaller toolsInstaller;
     private final File localTemporaryDir;
+    private final RootShell rootShell;
     private final Map<Tunnel, Config> runningConfigs = new HashMap<>();
+    private final ToolsInstaller toolsInstaller;
     private boolean multipleTunnels;
 
     public WgQuickBackend(final Context context, final RootShell rootShell, final ToolsInstaller toolsInstaller) {
@@ -55,10 +54,6 @@ public final class WgQuickBackend implements Backend {
         this.toolsInstaller = toolsInstaller;
     }
 
-    public void setMultipleTunnels(boolean on) {
-        multipleTunnels = on;
-    }
-
     @Override
     public Set<String> getRunningTunnelNames() {
         final List<String> output = new ArrayList<>();
@@ -110,6 +105,10 @@ public final class WgQuickBackend implements Backend {
         return output.get(0);
     }
 
+    public void setMultipleTunnels(boolean on) {
+        multipleTunnels = on;
+    }
+
     @Override
     public State setState(final Tunnel tunnel, State state, @Nullable final Config config) throws Exception {
         final State originalState = getState(tunnel);
@@ -135,7 +134,8 @@ public final class WgQuickBackend implements Backend {
                         for (final Pair<Tunnel, Config> entry : rewind) {
                             setStateInternal(entry.first, entry.second, State.UP);
                         }
-                    } catch (final Exception ignored) { }
+                    } catch (final Exception ignored) {
+                    }
                     throw e;
                 }
             }
@@ -153,7 +153,8 @@ public final class WgQuickBackend implements Backend {
                             setStateInternal(entry.getKey(), entry.getValue(), State.UP);
                         }
                     }
-                } catch (final Exception ignored) { }
+                } catch (final Exception ignored) {
+                }
                 throw e;
             }
         } else if (state == State.DOWN) {

tunnel/src/main/java/com/wireguard/android/util/ModuleLoader.java

@@ -39,15 +39,14 @@ import androidx.annotation.Nullable;
 
 @NonNullForAll
 public class ModuleLoader {
-    private static final String MODULE_PUBLIC_KEY_BASE64 = "RWRmHuT9PSqtwfsLtEx+QS06BJtLgFYteL9WCNjH7yuyu5Y1DieSN7If";
     private static final String MODULE_LIST_URL = "https://download.wireguard.com/android-module/modules.txt.sig";
-    private static final String MODULE_URL = "https://download.wireguard.com/android-module/%s";
     private static final String MODULE_NAME = "wireguard-%s.ko";
-
+    private static final String MODULE_PUBLIC_KEY_BASE64 = "RWRmHuT9PSqtwfsLtEx+QS06BJtLgFYteL9WCNjH7yuyu5Y1DieSN7If";
-    private final RootShell rootShell;
+    private static final String MODULE_URL = "https://download.wireguard.com/android-module/%s";
-    private final String userAgent;
     private final File moduleDir;
+    private final RootShell rootShell;
     private final File tmpDir;
+    private final String userAgent;
 
     public ModuleLoader(final Context context, final RootShell rootShell, final String userAgent) {
         moduleDir = new File(context.getCacheDir(), "kmod");
@@ -56,27 +55,75 @@ public class ModuleLoader {
         this.userAgent = userAgent;
     }
 
-    public boolean moduleMightExist() {
+    public static boolean isModuleLoaded() {
-        return moduleDir.exists() && moduleDir.isDirectory();
+        return new File("/sys/module/wireguard").exists();
+    }
+
+    public Integer download() throws IOException, RootShellException, NoSuchAlgorithmException {
+        final List<String> output = new ArrayList<>();
+        rootShell.run(output, "sha256sum /proc/version|cut -d ' ' -f 1");
+        if (output.size() != 1 || output.get(0).length() != 64)
+            throw new InvalidParameterException("Invalid sha256 of /proc/version");
+        final String moduleName = String.format(MODULE_NAME, output.get(0));
+        HttpURLConnection connection = (HttpURLConnection) new URL(MODULE_LIST_URL).openConnection();
+        connection.setRequestProperty("User-Agent", userAgent);
+        connection.connect();
+        if (connection.getResponseCode() != HttpURLConnection.HTTP_OK)
+            throw new IOException("Hash list could not be found");
+        byte[] input = new byte[1024 * 1024 * 3 /* 3MiB */];
+        int len;
+        try (final InputStream inputStream = connection.getInputStream()) {
+            len = inputStream.read(input);
+        }
+        if (len <= 0)
+            throw new IOException("Hash list was empty");
+        final Map<String, Sha256Digest> modules = verifySignedHashes(new String(input, 0, len, StandardCharsets.UTF_8));
+        if (modules == null)
+            throw new InvalidParameterException("The signature did not verify or invalid hash list format");
+        if (!modules.containsKey(moduleName))
+            return OsConstants.ENOENT;
+        connection = (HttpURLConnection) new URL(String.format(MODULE_URL, moduleName)).openConnection();
+        connection.setRequestProperty("User-Agent", userAgent);
+        connection.connect();
+        if (connection.getResponseCode() != HttpURLConnection.HTTP_OK)
+            throw new IOException("Module file could not be found, despite being on hash list");
+
+        tmpDir.mkdirs();
+        moduleDir.mkdir();
+        File tempFile = null;
+        try {
+            tempFile = File.createTempFile("UNVERIFIED-", null, tmpDir);
+            MessageDigest digest = MessageDigest.getInstance("SHA-256");
+            try (final InputStream inputStream = connection.getInputStream();
+                 final FileOutputStream outputStream = new FileOutputStream(tempFile)) {
+                int total = 0;
+                while ((len = inputStream.read(input)) > 0) {
+                    total += len;
+                    if (total > 1024 * 1024 * 15 /* 15 MiB */)
+                        throw new IOException("File too big");
+                    outputStream.write(input, 0, len);
+                    digest.update(input, 0, len);
+                }
+                outputStream.getFD().sync();
+            }
+            if (!Arrays.equals(digest.digest(), modules.get(moduleName).bytes))
+                throw new IOException("Incorrect file hash");
+
+            if (!tempFile.renameTo(new File(moduleDir, moduleName)))
+                throw new IOException("Unable to rename to final destination");
+        } finally {
+            if (tempFile != null)
+                tempFile.delete();
+        }
+        return OsConstants.EXIT_SUCCESS;
     }
 
     public void loadModule() throws IOException, RootShellException {
         rootShell.run(null, String.format("insmod \"%s/wireguard-$(sha256sum /proc/version|cut -d ' ' -f 1).ko\"", moduleDir.getAbsolutePath()));
     }
 
-    public static boolean isModuleLoaded() {
+    public boolean moduleMightExist() {
-        return new File("/sys/module/wireguard").exists();
+        return moduleDir.exists() && moduleDir.isDirectory();
-    }
-
-    private static final class Sha256Digest {
-        private byte[] bytes;
-        private Sha256Digest(final String hex) {
-            if (hex.length() != 64)
-                throw new InvalidParameterException("SHA256 hashes must be 32 bytes long");
-            bytes = new byte[32];
-            for (int i = 0; i < 32; ++i)
-                bytes[i] = (byte)Integer.parseInt(hex.substring(i * 2, i * 2 + 2), 16);
-        }
     }
 
     @Nullable
@@ -127,62 +174,15 @@ public class ModuleLoader {
         return hashes;
     }
 
-    public Integer download() throws IOException, RootShellException, NoSuchAlgorithmException {
+    private static final class Sha256Digest {
-        final List<String> output = new ArrayList<>();
+        private byte[] bytes;
-        rootShell.run(output, "sha256sum /proc/version|cut -d ' ' -f 1");
-        if (output.size() != 1 || output.get(0).length() != 64)
-            throw new InvalidParameterException("Invalid sha256 of /proc/version");
-        final String moduleName = String.format(MODULE_NAME, output.get(0));
-        HttpURLConnection connection = (HttpURLConnection)new URL(MODULE_LIST_URL).openConnection();
-        connection.setRequestProperty("User-Agent", userAgent);
-        connection.connect();
-        if (connection.getResponseCode() != HttpURLConnection.HTTP_OK)
-            throw new IOException("Hash list could not be found");
-        byte[] input = new byte[1024 * 1024 * 3 /* 3MiB */];
-        int len;
-        try (final InputStream inputStream = connection.getInputStream()) {
-            len = inputStream.read(input);
-        }
-        if (len <= 0)
-            throw new IOException("Hash list was empty");
-        final Map<String, Sha256Digest> modules = verifySignedHashes(new String(input, 0, len, StandardCharsets.UTF_8));
-        if (modules == null)
-            throw new InvalidParameterException("The signature did not verify or invalid hash list format");
-        if (!modules.containsKey(moduleName))
-            return OsConstants.ENOENT;
-        connection = (HttpURLConnection)new URL(String.format(MODULE_URL, moduleName)).openConnection();
-        connection.setRequestProperty("User-Agent", userAgent);
-        connection.connect();
-        if (connection.getResponseCode() != HttpURLConnection.HTTP_OK)
-            throw new IOException("Module file could not be found, despite being on hash list");
 
-        tmpDir.mkdirs();
+        private Sha256Digest(final String hex) {
-        moduleDir.mkdir();
+            if (hex.length() != 64)
-        File tempFile = null;
+                throw new InvalidParameterException("SHA256 hashes must be 32 bytes long");
-        try {
+            bytes = new byte[32];
-            tempFile = File.createTempFile("UNVERIFIED-", null, tmpDir);
+            for (int i = 0; i < 32; ++i)
-            MessageDigest digest = MessageDigest.getInstance("SHA-256");
+                bytes[i] = (byte) Integer.parseInt(hex.substring(i * 2, i * 2 + 2), 16);
-            try (final InputStream inputStream = connection.getInputStream();
-                 final FileOutputStream outputStream = new FileOutputStream(tempFile)) {
-                int total = 0;
-                while ((len = inputStream.read(input)) > 0) {
-                    total += len;
-                    if (total > 1024 * 1024 * 15 /* 15 MiB */)
-                        throw new IOException("File too big");
-                    outputStream.write(input, 0, len);
-                    digest.update(input, 0, len);
-                }
-                outputStream.getFD().sync();
-            }
-            if (!Arrays.equals(digest.digest(), modules.get(moduleName).bytes))
-                throw new IOException("Incorrect file hash");
-
-            if (!tempFile.renameTo(new File(moduleDir, moduleName)))
-                throw new IOException("Unable to rename to final destination");
-        } finally {
-            if (tempFile != null)
-                tempFile.delete();
         }
-        return OsConstants.EXIT_SUCCESS;
     }
 }

tunnel/src/main/java/com/wireguard/android/util/RootShell.java

@@ -187,6 +187,25 @@ public class RootShell {
     }
 
     public static class RootShellException extends Exception {
+        private final Object[] format;
+        private final Reason reason;
+        public RootShellException(final Reason reason, final Object... format) {
+            this.reason = reason;
+            this.format = format;
+        }
+
+        public Object[] getFormat() {
+            return format;
+        }
+
+        public Reason getReason() {
+            return reason;
+        }
+
+        public boolean isIORelated() {
+            return reason != Reason.NO_ROOT_ACCESS;
+        }
+
         public enum Reason {
             NO_ROOT_ACCESS,
             SHELL_MARKER_COUNT_ERROR,
@@ -195,20 +214,5 @@ public class RootShell {
             CREATE_BIN_DIR_ERROR,
             CREATE_TEMP_DIR_ERROR
         }
-        private final Reason reason;
-        private final Object[] format;
-        public RootShellException(final Reason reason, final Object ...format) {
-            this.reason = reason;
-            this.format = format;
-        }
-        public boolean isIORelated() {
-            return reason != Reason.NO_ROOT_ACCESS;
-        }
-        public Reason getReason() {
-            return reason;
-        }
-        public Object[] getFormat() {
-            return format;
-        }
     }
 }

tunnel/src/main/java/com/wireguard/android/util/ToolsInstaller.java

@@ -40,9 +40,9 @@ public final class ToolsInstaller {
     private static final String TAG = "WireGuard/" + ToolsInstaller.class.getSimpleName();
 
     private final Context context;
-    private final RootShell rootShell;
     private final File localBinaryDir;
     private final Object lock = new Object();
+    private final RootShell rootShell;
     @Nullable private Boolean areToolsAvailable;
     @Nullable private Boolean installAsMagiskModule;
 
@@ -107,6 +107,29 @@ public final class ToolsInstaller {
         }
     }
 
+    public boolean extract() throws IOException {
+        localBinaryDir.mkdirs();
+        final File files[] = new File[EXECUTABLES.length];
+        final File tempFiles[] = new File[EXECUTABLES.length];
+        boolean allExist = true;
+        for (int i = 0; i < files.length; ++i) {
+            files[i] = new File(localBinaryDir, EXECUTABLES[i]);
+            tempFiles[i] = new File(localBinaryDir, EXECUTABLES[i] + ".tmp");
+            allExist &= files[i].exists();
+        }
+        if (allExist)
+            return false;
+        for (int i = 0; i < files.length; ++i) {
+            if (!SharedLibraryLoader.extractLibrary(context, EXECUTABLES[i], tempFiles[i]))
+                throw new FileNotFoundException("Unable to find " + EXECUTABLES[i]);
+            if (!tempFiles[i].setExecutable(true, false))
+                throw new IOException("Unable to mark " + tempFiles[i].getAbsolutePath() + " as executable");
+            if (!tempFiles[i].renameTo(files[i]))
+                throw new IOException("Unable to rename " + tempFiles[i].getAbsolutePath() + " to " + files[i].getAbsolutePath());
+        }
+        return true;
+    }
+
     public int install() throws RootShellException, IOException {
         if (!context.getPackageName().startsWith("com.wireguard."))
             throw new SecurityException("The tools may only be installed system-wide from the main WireGuard app.");
@@ -161,29 +184,6 @@ public final class ToolsInstaller {
         }
     }
 
-    public boolean extract() throws IOException {
-        localBinaryDir.mkdirs();
-        final File files[] = new File[EXECUTABLES.length];
-        final File tempFiles[] = new File[EXECUTABLES.length];
-        boolean allExist = true;
-        for (int i = 0; i < files.length; ++i) {
-            files[i] = new File(localBinaryDir, EXECUTABLES[i]);
-            tempFiles[i] = new File(localBinaryDir, EXECUTABLES[i] + ".tmp");
-            allExist &= files[i].exists();
-        }
-        if (allExist)
-            return false;
-        for (int i = 0; i < files.length; ++i) {
-            if (!SharedLibraryLoader.extractLibrary(context, EXECUTABLES[i], tempFiles[i]))
-                throw new FileNotFoundException("Unable to find " + EXECUTABLES[i]);
-            if (!tempFiles[i].setExecutable(true, false))
-                throw new IOException("Unable to mark " + tempFiles[i].getAbsolutePath() + " as executable");
-            if (!tempFiles[i].renameTo(files[i]))
-                throw new IOException("Unable to rename " + tempFiles[i].getAbsolutePath() + " to " + files[i].getAbsolutePath());
-        }
-        return true;
-    }
-
     private boolean willInstallAsMagiskModule() {
         synchronized (lock) {
             if (installAsMagiskModule == null) {

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

@@ -35,7 +35,8 @@ public final class InetAddresses {
         PARSER_METHOD = m;
     }
 
-    private InetAddresses() { }
+    private InetAddresses() {
+    }
 
     /**
      * Parses a numeric IPv4 or IPv6 address without performing any DNS lookups.

tunnel/src/main/java/com/wireguard/config/ParseException.java

@@ -10,6 +10,7 @@ import com.wireguard.util.NonNullForAll;
 import androidx.annotation.Nullable;
 
 /**
+ *
  */
 @NonNullForAll
 public class ParseException extends Exception {

tunnel/src/main/java/com/wireguard/crypto/Key.java

@@ -204,6 +204,16 @@ public final class Key {
         return new Key(publicKey);
     }
 
+    @Override
+    public boolean equals(final Object obj) {
+        if (obj == this)
+            return true;
+        if (obj == null || obj.getClass() != getClass())
+            return false;
+        final Key other = (Key) obj;
+        return MessageDigest.isEqual(key, other.key);
+    }
+
     /**
      * Returns the key as an array of bytes.
      *
@@ -214,6 +224,14 @@ public final class Key {
         return Arrays.copyOf(key, key.length);
     }
 
+    @Override
+    public int hashCode() {
+        int ret = 0;
+        for (int i = 0; i < key.length / 4; ++i)
+            ret ^= (key[i * 4 + 0] >> 0) + (key[i * 4 + 1] >> 8) + (key[i * 4 + 2] >> 16) + (key[i * 4 + 3] >> 24);
+        return ret;
+    }
+
     /**
      * Encodes the key to base64.
      *
@@ -250,24 +268,6 @@ public final class Key {
         return new String(output);
     }
 
-    @Override
-    public int hashCode() {
-        int ret = 0;
-        for (int i = 0; i < key.length / 4; ++i)
-            ret ^= (key[i * 4 + 0] >> 0) + (key[i * 4 + 1] >> 8) + (key[i * 4 + 2] >> 16) + (key[i * 4 + 3] >> 24);
-        return ret;
-    }
-
-    @Override
-    public boolean equals(final Object obj) {
-        if (obj == this)
-            return true;
-        if (obj == null || obj.getClass() != getClass())
-            return false;
-        final Key other = (Key) obj;
-        return MessageDigest.isEqual(key, other.key);
-    }
-
     /**
      * The supported formats for encoding a WireGuard key.
      */

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

@@ -37,17 +37,16 @@ import java9.util.concurrent.CompletableFuture;
 
 @NonNullForAll
 public class Application extends android.app.Application implements SharedPreferences.OnSharedPreferenceChangeListener {
-    private static final String TAG = "WireGuard/" + Application.class.getSimpleName();
     public static final String USER_AGENT = String.format(Locale.ENGLISH, "WireGuard/%s (Android %d; %s; %s; %s %s; %s)", BuildConfig.VERSION_NAME, Build.VERSION.SDK_INT, Build.SUPPORTED_ABIS.length > 0 ? Build.SUPPORTED_ABIS[0] : "unknown ABI", Build.BOARD, Build.MANUFACTURER, Build.MODEL, Build.FINGERPRINT);
-
+    private static final String TAG = "WireGuard/" + Application.class.getSimpleName();
     @SuppressWarnings("NullableProblems") private static WeakReference<Application> weakSelf;
     private final CompletableFuture<Backend> futureBackend = new CompletableFuture<>();
     @SuppressWarnings("NullableProblems") private AsyncWorker asyncWorker;
     @Nullable private Backend backend;
+    @SuppressWarnings("NullableProblems") private ModuleLoader moduleLoader;
     @SuppressWarnings("NullableProblems") private RootShell rootShell;
     @SuppressWarnings("NullableProblems") private SharedPreferences sharedPreferences;
     @SuppressWarnings("NullableProblems") private ToolsInstaller toolsInstaller;
-    @SuppressWarnings("NullableProblems") private ModuleLoader moduleLoader;
     @SuppressWarnings("NullableProblems") private TunnelManager tunnelManager;
 
     public Application() {
@@ -102,6 +101,10 @@ public class Application extends android.app.Application implements SharedPrefer
         return get().futureBackend;
     }
 
+    public static ModuleLoader getModuleLoader() {
+        return get().moduleLoader;
+    }
+
     public static RootShell getRootShell() {
         return get().rootShell;
     }
@@ -114,10 +117,6 @@ public class Application extends android.app.Application implements SharedPrefer
         return get().toolsInstaller;
     }
 
-    public static ModuleLoader getModuleLoader() {
-        return get().moduleLoader;
-    }
-
     public static TunnelManager getTunnelManager() {
         return get().tunnelManager;
     }
@@ -167,15 +166,15 @@ public class Application extends android.app.Application implements SharedPrefer
         sharedPreferences.registerOnSharedPreferenceChangeListener(this);
     }
 
+    @Override
+    public void onSharedPreferenceChanged(final SharedPreferences sharedPreferences, final String key) {
+        if ("multiple_tunnels".equals(key) && backend != null && backend instanceof WgQuickBackend)
+            ((WgQuickBackend) backend).setMultipleTunnels(sharedPreferences.getBoolean(key, false));
+    }
+
     @Override
     public void onTerminate() {
         sharedPreferences.unregisterOnSharedPreferenceChangeListener(this);
         super.onTerminate();
     }
-
-    @Override
-    public void onSharedPreferenceChanged(final SharedPreferences sharedPreferences, final String key) {
-        if ("multiple_tunnels".equals(key) && backend != null && backend instanceof WgQuickBackend)
-            ((WgQuickBackend)backend).setMultipleTunnels(sharedPreferences.getBoolean(key, false));
-    }
 }

ui/src/main/java/com/wireguard/android/fragment/TunnelDetailFragment.java

@@ -34,8 +34,20 @@ import androidx.databinding.DataBindingUtil;
 @NonNullForAll
 public class TunnelDetailFragment extends BaseFragment {
     @Nullable private TunnelDetailFragmentBinding binding;
-    @Nullable private Timer timer;
     @Nullable private State lastState = State.TOGGLE;
+    @Nullable private Timer timer;
+
+    private String formatBytes(final long bytes) {
+        if (bytes < 1024)
+            return requireContext().getString(R.string.transfer_bytes, bytes);
+        else if (bytes < 1024 * 1024)
+            return requireContext().getString(R.string.transfer_kibibytes, bytes / 1024.0);
+        else if (bytes < 1024 * 1024 * 1024)
+            return requireContext().getString(R.string.transfer_mibibytes, bytes / (1024.0 * 1024.0));
+        else if (bytes < 1024 * 1024 * 1024 * 1024)
+            return requireContext().getString(R.string.transfer_gibibytes, bytes / (1024.0 * 1024.0 * 1024.0));
+        return requireContext().getString(R.string.transfer_tibibytes, bytes / (1024.0 * 1024.0 * 1024.0) / 1024.0);
+    }
 
     @Override
     public void onCreate(@Nullable final Bundle savedInstanceState) {
@@ -48,27 +60,6 @@ public class TunnelDetailFragment extends BaseFragment {
         inflater.inflate(R.menu.tunnel_detail, menu);
     }
 
-    @Override
-    public void onStop() {
-        super.onStop();
-        if (timer != null) {
-            timer.cancel();
-            timer = null;
-        }
-    }
-
-    @Override
-    public void onResume() {
-        super.onResume();
-        timer = new Timer();
-        timer.scheduleAtFixedRate(new TimerTask() {
-            @Override
-            public void run() {
-                updateStats();
-            }
-        }, 0, 1000);
-    }
-
     @Override
     public View onCreateView(final LayoutInflater inflater, @Nullable final ViewGroup container,
                              @Nullable final Bundle savedInstanceState) {
@@ -86,6 +77,18 @@ public class TunnelDetailFragment extends BaseFragment {
         super.onDestroyView();
     }
 
+    @Override
+    public void onResume() {
+        super.onResume();
+        timer = new Timer();
+        timer.scheduleAtFixedRate(new TimerTask() {
+            @Override
+            public void run() {
+                updateStats();
+            }
+        }, 0, 1000);
+    }
+
     @Override
     public void onSelectedTunnelChanged(@Nullable final ObservableTunnel oldTunnel, @Nullable final ObservableTunnel newTunnel) {
         if (binding == null)
@@ -99,6 +102,15 @@ public class TunnelDetailFragment extends BaseFragment {
         updateStats();
     }
 
+    @Override
+    public void onStop() {
+        super.onStop();
+        if (timer != null) {
+            timer.cancel();
+            timer = null;
+        }
+    }
+
     @Override
     public void onViewStateRestored(@Nullable final Bundle savedInstanceState) {
         if (binding == null) {
@@ -110,18 +122,6 @@ public class TunnelDetailFragment extends BaseFragment {
         super.onViewStateRestored(savedInstanceState);
     }
 
-    private String formatBytes(final long bytes) {
-        if (bytes < 1024)
-            return requireContext().getString(R.string.transfer_bytes, bytes);
-        else if (bytes < 1024*1024)
-            return requireContext().getString(R.string.transfer_kibibytes, bytes/1024.0);
-        else if (bytes < 1024*1024*1024)
-            return requireContext().getString(R.string.transfer_mibibytes, bytes/(1024.0*1024.0));
-        else if (bytes < 1024*1024*1024*1024)
-            return requireContext().getString(R.string.transfer_gibibytes, bytes/(1024.0*1024.0*1024.0));
-        return requireContext().getString(R.string.transfer_tibibytes, bytes/(1024.0*1024.0*1024.0)/1024.0);
-    }
-
     private void updateStats() {
         if (binding == null || !isResumed())
             return;

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

@@ -262,14 +262,6 @@ public class TunnelListFragment extends BaseFragment {
         });
     }
 
-    private void showSnackbar(final CharSequence message) {
-        if (binding != null) {
-            final Snackbar snackbar = Snackbar.make(binding.mainContainer, message, Snackbar.LENGTH_LONG);
-            snackbar.setAnchorView(binding.createFab);
-            snackbar.show();
-        }
-    }
-
     private void onTunnelDeletionFinished(final Integer count, @Nullable final Throwable throwable) {
         final String message;
         if (throwable == null) {
@@ -337,6 +329,14 @@ public class TunnelListFragment extends BaseFragment {
         });
     }
 
+    private void showSnackbar(final CharSequence message) {
+        if (binding != null) {
+            final Snackbar snackbar = Snackbar.make(binding.mainContainer, message, Snackbar.LENGTH_LONG);
+            snackbar.setAnchorView(binding.createFab);
+            snackbar.show();
+        }
+    }
+
     private MultiselectableRelativeLayout viewForTunnel(final ObservableTunnel tunnel, final List tunnels) {
         return (MultiselectableRelativeLayout) binding.tunnelList.findViewHolderForAdapterPosition(tunnels.indexOf(tunnel)).itemView;
     }

ui/src/main/java/com/wireguard/android/model/ObservableTunnel.java

@@ -27,12 +27,12 @@ import java9.util.concurrent.CompletionStage;
 public class ObservableTunnel extends BaseObservable implements Keyed<String>, Tunnel {
     private final TunnelManager manager;
     @Nullable private Config config;
-    private State state;
     private String name;
+    private State state;
     @Nullable private Statistics statistics;
 
     ObservableTunnel(final TunnelManager manager, final String name,
-           @Nullable final Config config, final State state) {
+                     @Nullable final Config config, final State state) {
         this.name = name;
         this.manager = manager;
         this.config = config;
@@ -103,6 +103,11 @@ public class ObservableTunnel extends BaseObservable implements Keyed<String>, T
         return name;
     }
 
+    @Override
+    public void onStateChange(final State newState) {
+        onStateChanged(newState);
+    }
+
     State onStateChanged(final State state) {
         if (state != State.UP)
             onStatisticsChanged(null);
@@ -111,11 +116,6 @@ public class ObservableTunnel extends BaseObservable implements Keyed<String>, T
         return state;
     }
 
-    @Override
-    public void onStateChange(final State newState) {
-        onStateChanged(newState);
-    }
-
     @Nullable
     Statistics onStatisticsChanged(@Nullable final Statistics statistics) {
         this.statistics = statistics;

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

@@ -47,8 +47,7 @@ public class LogExporterPreference extends Preference {
                 final Process process = Runtime.getRuntime().exec(new String[]{
                         "logcat", "-b", "all", "-d", "-v", "threadtime", "*:V"});
                 try (final BufferedReader stdout = new BufferedReader(new InputStreamReader(process.getInputStream()));
-                     final BufferedReader stderr = new BufferedReader(new InputStreamReader(process.getErrorStream())))
+                     final BufferedReader stderr = new BufferedReader(new InputStreamReader(process.getErrorStream()))) {
-                {
                     String line;
                     while ((line = stdout.readLine()) != null) {
                         outputFile.getOutputStream().write(line.getBytes());

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

@@ -28,14 +28,6 @@ import androidx.preference.Preference;
 public class VersionPreference extends Preference {
     @Nullable private String versionSummary;
 
-    private String getBackendPrettyName(final Context context, final Backend backend) {
-        if (backend instanceof GoBackend)
-            return context.getString(R.string.type_name_kernel_module);
-        if (backend instanceof WgQuickBackend)
-            return context.getString(R.string.type_name_go_userspace);
-        return "";
-    }
-
     public VersionPreference(final Context context, final AttributeSet attrs) {
         super(context, attrs);
 
@@ -50,6 +42,14 @@ public class VersionPreference extends Preference {
         });
     }
 
+    private String getBackendPrettyName(final Context context, final Backend backend) {
+        if (backend instanceof GoBackend)
+            return context.getString(R.string.type_name_kernel_module);
+        if (backend instanceof WgQuickBackend)
+            return context.getString(R.string.type_name_go_userspace);
+        return "";
+    }
+
     @Nullable
     @Override
     public CharSequence getSummary() {

ui/src/main/java/com/wireguard/android/util/DownloadsFileSaver.java

@@ -26,30 +26,6 @@ import java.io.OutputStream;
 @NonNullForAll
 public class DownloadsFileSaver {
 
-    public static class DownloadsFile {
-        private Context context;
-        private OutputStream outputStream;
-        private String fileName;
-        private Uri uri;
-
-        private DownloadsFile(final Context context, final OutputStream outputStream, final String fileName, final Uri uri) {
-            this.context = context;
-            this.outputStream = outputStream;
-            this.fileName = fileName;
-            this.uri = uri;
-        }
-
-        public OutputStream getOutputStream() { return outputStream; }
-        public String getFileName() { return fileName; }
-
-        public void delete() {
-            if (Build.VERSION.SDK_INT >= Build.VERSION_CODES.Q)
-                context.getContentResolver().delete(uri, null, null);
-            else
-                new File(fileName).delete();
-        }
-    }
-
     public static DownloadsFile save(final Context context, final String name, final String mimeType, final boolean overwriteExisting) throws Exception {
         if (Build.VERSION.SDK_INT >= Build.VERSION_CODES.Q) {
             final ContentResolver contentResolver = context.getContentResolver();
@@ -89,12 +65,40 @@ public class DownloadsFileSaver {
             }
             return new DownloadsFile(context, contentStream, path, contentUri);
         } else {
-            @SuppressWarnings("deprecation")
+            @SuppressWarnings("deprecation") final File path = Environment.getExternalStoragePublicDirectory(Environment.DIRECTORY_DOWNLOADS);
-            final File path = Environment.getExternalStoragePublicDirectory(Environment.DIRECTORY_DOWNLOADS);
             final File file = new File(path, name);
             if (!path.isDirectory() && !path.mkdirs())
                 throw new IOException(context.getString(R.string.create_output_dir_error));
             return new DownloadsFile(context, new FileOutputStream(file), file.getAbsolutePath(), null);
         }
     }
+
+    public static class DownloadsFile {
+        private Context context;
+        private String fileName;
+        private OutputStream outputStream;
+        private Uri uri;
+
+        private DownloadsFile(final Context context, final OutputStream outputStream, final String fileName, final Uri uri) {
+            this.context = context;
+            this.outputStream = outputStream;
+            this.fileName = fileName;
+            this.uri = uri;
+        }
+
+        public void delete() {
+            if (Build.VERSION.SDK_INT >= Build.VERSION_CODES.Q)
+                context.getContentResolver().delete(uri, null, null);
+            else
+                new File(fileName).delete();
+        }
+
+        public String getFileName() {
+            return fileName;
+        }
+
+        public OutputStream getOutputStream() {
+            return outputStream;
+        }
+    }
 }

ui/src/main/java/com/wireguard/android/util/ErrorMessages.java

@@ -51,14 +51,6 @@ public final class ErrorMessages {
             BackendException.Reason.TUN_CREATION_ERROR, R.string.tun_create_error,
             BackendException.Reason.GO_ACTIVATION_ERROR_CODE, R.string.tunnel_on_error
     ));
-    private static final Map<RootShellException.Reason, Integer> RSE_REASON_MAP = new EnumMap<>(Maps.of(
-            RootShellException.Reason.NO_ROOT_ACCESS, R.string.error_root,
-            RootShellException.Reason.SHELL_MARKER_COUNT_ERROR, R.string.shell_marker_count_error,
-            RootShellException.Reason.SHELL_EXIT_STATUS_READ_ERROR, R.string.shell_exit_status_read_error,
-            RootShellException.Reason.SHELL_START_ERROR, R.string.shell_start_error,
-            RootShellException.Reason.CREATE_BIN_DIR_ERROR, R.string.create_bin_dir_error,
-            RootShellException.Reason.CREATE_TEMP_DIR_ERROR, R.string.create_temp_dir_error
-    ));
     private static final Map<Format, Integer> KFE_FORMAT_MAP = new EnumMap<>(Maps.of(
             Format.BASE64, R.string.key_length_explanation_base64,
             Format.BINARY, R.string.key_length_explanation_binary,
@@ -74,6 +66,14 @@ public final class ErrorMessages {
             InetNetwork.class, R.string.parse_error_inet_network,
             Integer.class, R.string.parse_error_integer
     );
+    private static final Map<RootShellException.Reason, Integer> RSE_REASON_MAP = new EnumMap<>(Maps.of(
+            RootShellException.Reason.NO_ROOT_ACCESS, R.string.error_root,
+            RootShellException.Reason.SHELL_MARKER_COUNT_ERROR, R.string.shell_marker_count_error,
+            RootShellException.Reason.SHELL_EXIT_STATUS_READ_ERROR, R.string.shell_exit_status_read_error,
+            RootShellException.Reason.SHELL_START_ERROR, R.string.shell_start_error,
+            RootShellException.Reason.CREATE_BIN_DIR_ERROR, R.string.create_bin_dir_error,
+            RootShellException.Reason.CREATE_TEMP_DIR_ERROR, R.string.create_temp_dir_error
+    ));
 
     private ErrorMessages() {
         // Prevent instantiation