v1.7.1: Fix Android 9 crash and Kernel-VPN compatibility

inventory69 · inventory69 · commit df4ee4bed024 · 2026-01-30T16:21:04.000+01:00
- Fix connection leak on Android 9 (close() in finally block) - Fix VPN detection for Kernel Wireguard (interface name patterns) - Fix missing files after app data clear (local existence check) - Update changelogs for v1.7.1 (versionCode 18) Refs: #15
diff --git a/CHANGELOG.de.md b/CHANGELOG.de.md
@@ -8,6 +8,33 @@ Das Format basiert auf [Keep a Changelog](https://keepachangelog.com/en/1.0.0/).
 
 ---
 
+## [1.7.1] - 2026-01-30
+
+### 🐛 Kritische Fehlerbehebungen
+
+- **App-Absturz auf Android 9 nach längerer Nutzung behoben** ([ref #15](https://github.com/inventory69/simple-notes-sync/issues/15))
+  - Ressourcenerschöpfung durch nicht geschlossene HTTP-Verbindungen behoben
+  - App konnte nach ~30-45 Minuten Nutzung durch angesammelte Connection-Leaks abstürzen
+  - Danke an [@roughnecks] für den detaillierten Fehlerbericht!
+
+- **VPN-Kompatibilitäts-Regression behoben** ([ref #11](https://github.com/inventory69/simple-notes-sync/issues/11))
+  - WiFi Socket-Binding erkennt jetzt korrekt Wireguard VPN-Interfaces (tun*, wg*, *-wg-*)
+  - Traffic wird korrekt durch VPN-Tunnel geleitet statt direkt über WiFi
+  - Behebt "Verbindungs-Timeout" beim Sync zu externen Servern über VPN
+
+### 🔧 Technische Änderungen
+
+- Neue `SafeSardineWrapper` Klasse stellt korrektes HTTP-Connection-Cleanup sicher
+- Weniger unnötige 401-Authentifizierungs-Challenges durch preemptive Auth-Header
+- ProGuard-Regel hinzugefügt um harmlose TextInclusionStrategy-Warnungen zu unterdrücken
+- VPN-Interface-Erkennung via `NetworkInterface.getNetworkInterfaces()` Pattern-Matching
+
+### 🌍 Lokalisierung
+
+- Hardcodierte deutsche Fehlermeldungen behoben - jetzt String-Resources für korrekte Lokalisierung
+
+---
+
 ## [1.7.0] - 2026-01-26
 
 ### 🎉 Major: Grid-Ansicht, Nur-WLAN Sync & VPN-Unterstützung
diff --git a/CHANGELOG.md b/CHANGELOG.md
@@ -17,11 +17,21 @@ The format is based on [Keep a Changelog](https://keepachangelog.com/en/1.0.0/).
   - App could crash after ~30-45 minutes of use due to accumulated connection leaks
   - Thanks to [@roughnecks] for the detailed bug report!
 
+- **Fixed VPN compatibility regression** ([ref #11](https://github.com/inventory69/simple-notes-sync/issues/11))
+  - WiFi socket binding now correctly detects Wireguard VPN interfaces (tun*, wg*, *-wg-*)
+  - Traffic routes through VPN tunnel instead of bypassing it directly to WiFi
+  - Fixes "Connection timeout" when syncing to external servers via VPN
+
 ### 🔧 Technical Changes
 
 - New `SafeSardineWrapper` class ensures proper HTTP connection cleanup
 - Reduced unnecessary 401 authentication challenges with preemptive auth headers
 - Added ProGuard rule to suppress harmless TextInclusionStrategy warnings on older Android versions
+- VPN interface detection via `NetworkInterface.getNetworkInterfaces()` pattern matching
+
+### 🌍 Localization
+
+- Fixed hardcoded German error messages - now uses string resources for proper localization
 
 ---
 
diff --git a/android/app/src/main/java/dev/dettmer/simplenotes/MainActivity.kt b/android/app/src/main/java/dev/dettmer/simplenotes/MainActivity.kt
@@ -392,21 +392,21 @@ class MainActivity : AppCompatActivity() {
                     // 🔥 v1.1.2: Check if there are unsynced changes first (performance optimization)
                     if (!syncService.hasUnsyncedChanges()) {
                         Logger.d(TAG, "⏭️ No unsynced changes, skipping server reachability check")
-                        SyncStateManager.markCompleted("Bereits synchronisiert")
+                        SyncStateManager.markCompleted(getString(R.string.snackbar_already_synced))
                         return@launch
                     }
                     
                     // Check if server is reachable
                     if (!syncService.isServerReachable()) {
-                        SyncStateManager.markError("Server nicht erreichbar")
+                        SyncStateManager.markError(getString(R.string.snackbar_server_unreachable))
                         return@launch
                     }
                     
                     // Perform sync
                     val result = syncService.syncNotes()
                     
                     if (result.isSuccess) {
-                        SyncStateManager.markCompleted("${result.syncedCount} Notizen")
+                        SyncStateManager.markCompleted(getString(R.string.snackbar_synced_count, result.syncedCount))
                         loadNotes()
                     } else {
                         SyncStateManager.markError(result.errorMessage)
@@ -683,7 +683,7 @@ class MainActivity : AppCompatActivity() {
                 
                 if (!isReachable) {
                     Logger.d(TAG, "⏭️ Manual Sync: Server not reachable - aborting")
-                    SyncStateManager.markError("Server nicht erreichbar")
+                    SyncStateManager.markError(getString(R.string.snackbar_server_unreachable))
                     return@launch
                 }
                 
diff --git a/android/app/src/main/java/dev/dettmer/simplenotes/SettingsActivity.kt b/android/app/src/main/java/dev/dettmer/simplenotes/SettingsActivity.kt
@@ -608,8 +608,8 @@ class SettingsActivity : AppCompatActivity() {
                 
                 // ⭐ WICHTIG: Server-Erreichbarkeits-Check VOR Sync (wie in anderen Triggern)
                 if (!syncService.isServerReachable()) {
-                    showToast("⚠️ Server nicht erreichbar")
-                    SyncStateManager.markError("Server nicht erreichbar")
+                    showToast("⚠️ ${getString(R.string.snackbar_server_unreachable)}")
+                    SyncStateManager.markError(getString(R.string.snackbar_server_unreachable))
                     checkServerStatus() // Server-Status aktualisieren
                     return@launch
                 }
diff --git a/android/app/src/main/java/dev/dettmer/simplenotes/sync/WebDavSyncService.kt b/android/app/src/main/java/dev/dettmer/simplenotes/sync/WebDavSyncService.kt
@@ -104,8 +104,45 @@ class WebDavSyncService(private val context: Context) {
         return sessionWifiAddress
     }
     
+    /**
+     * 🔒 v1.7.1: Checks if any VPN/Wireguard interface is active.
+     * 
+     * Wireguard VPNs run as separate network interfaces (tun*, wg*, *-wg-*),
+     * and are NOT detected via NetworkCapabilities.TRANSPORT_VPN!
+     * 
+     * @return true if VPN interface is detected
+     */
+    private fun isVpnInterfaceActive(): Boolean {
+        try {
+            val interfaces = NetworkInterface.getNetworkInterfaces() ?: return false
+            while (interfaces.hasMoreElements()) {
+                val iface = interfaces.nextElement()
+                if (!iface.isUp) continue
+                
+                val name = iface.name.lowercase()
+                // Check for VPN/Wireguard interface patterns:
+                // - tun0, tun1, etc. (OpenVPN, generic VPN)
+                // - wg0, wg1, etc. (Wireguard)
+                // - *-wg-* (Mullvad, ProtonVPN style: se-sto-wg-202)
+                if (name.startsWith("tun") || 
+                    name.startsWith("wg") || 
+                    name.contains("-wg-") ||
+                    name.startsWith("ppp")) {
+                    Logger.d(TAG, "🔒 VPN interface detected: ${iface.name}")
+                    return true
+                }
+            }
+        } catch (e: Exception) {
+            Logger.w(TAG, "⚠️ Failed to check VPN interfaces: ${e.message}")
+        }
+        return false
+    }
+    
     /**
      * Findet WiFi Interface IP-Adresse (um VPN zu umgehen)
+     * 
+     * 🔒 v1.7.1 Fix: Now detects Wireguard VPN interfaces and skips WiFi binding
+     * when VPN is active, so traffic routes through VPN tunnel correctly.
      */
     @Suppress("ReturnCount") // Early returns for network validation checks
     private fun getWiFiInetAddressInternal(): InetAddress? {
@@ -129,10 +166,17 @@ class WebDavSyncService(private val context: Context) {
                 return null
             }
             
-            // 🔒 v1.7.0: VPN-Detection - Skip WiFi binding when VPN is active
+            // 🔒 v1.7.0: VPN-Detection via NetworkCapabilities (standard Android VPN)
             // When VPN is active, traffic should route through VPN, not directly via WiFi
             if (capabilities.hasTransport(NetworkCapabilities.TRANSPORT_VPN)) {
-                Logger.d(TAG, "🔒 VPN detected - using default routing (traffic will go through VPN)")
+                Logger.d(TAG, "🔒 VPN detected (TRANSPORT_VPN) - using default routing")
+                return null
+            }
+            
+            // 🔒 v1.7.1: VPN-Detection via interface names (Wireguard, OpenVPN, etc.)
+            // Wireguard VPNs are NOT detected via TRANSPORT_VPN, they run as separate interfaces!
+            if (isVpnInterfaceActive()) {
+                Logger.d(TAG, "🔒 VPN interface detected - skip WiFi binding, use default routing")
                 return null
             }
             
@@ -142,7 +186,7 @@ class WebDavSyncService(private val context: Context) {
                 return null
             }
             
-            Logger.d(TAG, "✅ Network is WiFi, searching for interface...")
+            Logger.d(TAG, "✅ Network is WiFi (no VPN), searching for interface...")
             
             @Suppress("LoopWithTooManyJumpStatements") // Network interface filtering requires multiple conditions
             // Finde WiFi Interface
@@ -649,19 +693,19 @@ class WebDavSyncService(private val context: Context) {
             SyncResult(
                 isSuccess = false,
                 errorMessage = when (e) {
-                    is java.net.UnknownHostException -> "Server nicht erreichbar"
-                    is java.net.SocketTimeoutException -> "Verbindungs-Timeout"
-                    is javax.net.ssl.SSLException -> "SSL-Fehler"
+                    is java.net.UnknownHostException -> context.getString(R.string.snackbar_server_unreachable)
+                    is java.net.SocketTimeoutException -> context.getString(R.string.snackbar_connection_timeout)
+                    is javax.net.ssl.SSLException -> context.getString(R.string.sync_error_ssl)
                     is com.thegrizzlylabs.sardineandroid.impl.SardineException -> {
                         when (e.statusCode) {
-                            401 -> "Authentifizierung fehlgeschlagen"
-                            403 -> "Zugriff verweigert"
-                            404 -> "Server-Pfad nicht gefunden"
-                            500 -> "Server-Fehler"
-                            else -> "HTTP-Fehler: ${e.statusCode}"
+                            401 -> context.getString(R.string.sync_error_auth_failed)
+                            403 -> context.getString(R.string.sync_error_access_denied)
+                            404 -> context.getString(R.string.sync_error_path_not_found)
+                            500 -> context.getString(R.string.sync_error_server)
+                            else -> context.getString(R.string.sync_error_http, e.statusCode)
                         }
                     }
-                    else -> e.message ?: "Unbekannter Fehler"
+                    else -> e.message ?: context.getString(R.string.sync_error_unknown)
                 }
             )
         }
@@ -824,19 +868,19 @@ class WebDavSyncService(private val context: Context) {
             SyncResult(
                 isSuccess = false,
                 errorMessage = when (e) {
-                    is java.net.UnknownHostException -> "Server nicht erreichbar: ${e.message}"
-                    is java.net.SocketTimeoutException -> "Verbindungs-Timeout: ${e.message}"
-                    is javax.net.ssl.SSLException -> "SSL-Fehler"
+                    is java.net.UnknownHostException -> "${context.getString(R.string.snackbar_server_unreachable)}: ${e.message}"
+                    is java.net.SocketTimeoutException -> "${context.getString(R.string.snackbar_connection_timeout)}: ${e.message}"
+                    is javax.net.ssl.SSLException -> context.getString(R.string.sync_error_ssl)
                     is com.thegrizzlylabs.sardineandroid.impl.SardineException -> {
                         when (e.statusCode) {
-                            401 -> "Authentifizierung fehlgeschlagen"
-                            403 -> "Zugriff verweigert"
-                            404 -> "Server-Pfad nicht gefunden"
-                            500 -> "Server-Fehler"
-                            else -> "HTTP-Fehler: ${e.statusCode}"
+                            401 -> context.getString(R.string.sync_error_auth_failed)
+                            403 -> context.getString(R.string.sync_error_access_denied)
+                            404 -> context.getString(R.string.sync_error_path_not_found)
+                            500 -> context.getString(R.string.sync_error_server)
+                            else -> context.getString(R.string.sync_error_http, e.statusCode)
                         }
                     }
-                    else -> e.message ?: "Unbekannter Fehler"
+                    else -> e.message ?: context.getString(R.string.sync_error_unknown)
                 }
             )
         }
@@ -1145,9 +1189,32 @@ class WebDavSyncService(private val context: Context) {
                             "modified=$serverModified lastSync=$lastSyncTime"
                     )
                     
+                    // FIRST: Check deletion tracker - if locally deleted, skip unless re-created on server
+                    if (deletionTracker.isDeleted(noteId)) {
+                        val deletedAt = deletionTracker.getDeletionTimestamp(noteId)
+                        
+                        // Smart check: Was note re-created on server after deletion?
+                        if (deletedAt != null && serverModified > deletedAt) {
+                            Logger.d(TAG, "   📝 Note re-created on server after deletion: $noteId")
+                            deletionTracker.removeDeletion(noteId)
+                            trackerModified = true
+                            // Continue with download below
+                        } else {
+                            Logger.d(TAG, "   ⏭️ Skipping deleted note: $noteId")
+                            skippedDeleted++
+                            processedIds.add(noteId)
+                            continue
+                        }
+                    }
+                    
+                    // Check if file exists locally
+                    val localNote = storage.loadNote(noteId)
+                    val fileExistsLocally = localNote != null
+                    
                     // PRIMARY: Timestamp check (works on first sync!)
                     // Same logic as Markdown sync - skip if not modified since last sync
-                    if (!forceOverwrite && lastSyncTime > 0 && serverModified <= lastSyncTime) {
+                    // BUT: Always download if file doesn't exist locally!
+                    if (!forceOverwrite && fileExistsLocally && lastSyncTime > 0 && serverModified <= lastSyncTime) {
                         skippedUnchanged++
                         Logger.d(TAG, "   ⏭️ Skipping $noteId: Not modified since last sync (timestamp)")
                         processedIds.add(noteId)
@@ -1156,13 +1223,19 @@ class WebDavSyncService(private val context: Context) {
                     
                     // SECONDARY: E-Tag check (for performance after first sync)
                     // Catches cases where file was re-uploaded with same content
-                    if (!forceOverwrite && serverETag != null && serverETag == cachedETag) {
+                    // BUT: Always download if file doesn't exist locally!
+                    if (!forceOverwrite && fileExistsLocally && serverETag != null && serverETag == cachedETag) {
                         skippedUnchanged++
                         Logger.d(TAG, "   ⏭️ Skipping $noteId: E-Tag match (content unchanged)")
                         processedIds.add(noteId)
                         continue
                     }
                     
+                    // If file doesn't exist locally, always download
+                    if (!fileExistsLocally) {
+                        Logger.d(TAG, "   📥 File missing locally - forcing download")
+                    }
+                    
                     // 🐛 DEBUG: Log download reason
                     val downloadReason = when {
                         lastSyncTime == 0L -> "First sync ever"
@@ -1179,28 +1252,9 @@ class WebDavSyncService(private val context: Context) {
                     val jsonContent = sardine.get(noteUrl).bufferedReader().use { it.readText() }
                     val remoteNote = Note.fromJson(jsonContent) ?: continue
                     
-                    // NEW: Check if note was deleted locally
-                    if (deletionTracker.isDeleted(remoteNote.id)) {
-                        val deletedAt = deletionTracker.getDeletionTimestamp(remoteNote.id)
-                        
-                        // Smart check: Was note re-created on server after deletion?
-                        if (deletedAt != null && remoteNote.updatedAt > deletedAt) {
-                            Logger.d(TAG, "   📝 Note re-created on server after deletion: ${remoteNote.id}")
-                            deletionTracker.removeDeletion(remoteNote.id)
-                            trackerModified = true
-                            // Continue with download below
-                        } else {
-                            Logger.d(TAG, "   ⏭️ Skipping deleted note: ${remoteNote.id}")
-                            skippedDeleted++
-                            processedIds.add(remoteNote.id)
-                            continue
-                        }
-                    }
-                    
                     processedIds.add(remoteNote.id)  // 🆕 Mark as processed
                     
-                    val localNote = storage.loadNote(remoteNote.id)
-                    
+                    // Note: localNote was already loaded above for existence check
                     when {
                         localNote == null -> {
                             // New note from server
diff --git a/android/app/src/main/res/values-de/strings.xml b/android/app/src/main/res/values-de/strings.xml
@@ -93,9 +93,21 @@
     <string name="snackbar_server_error">Server-Fehler: %s</string>
     <string name="snackbar_already_synced">Bereits synchronisiert</string>
     <string name="snackbar_server_unreachable">Server nicht erreichbar</string>
+    <string name="snackbar_connection_timeout">Verbindungs-Timeout</string>
     <string name="snackbar_synced_count">✅ Gesynct: %d Notizen</string>
     <string name="snackbar_nothing_to_sync">ℹ️ Nichts zu syncen</string>
     
+    <!-- ============================= -->
+    <!-- SYNC ERROR MESSAGES           -->
+    <!-- ============================= -->
+    <string name="sync_error_ssl">SSL-Fehler</string>
+    <string name="sync_error_auth_failed">Authentifizierung fehlgeschlagen</string>
+    <string name="sync_error_access_denied">Zugriff verweigert</string>
+    <string name="sync_error_path_not_found">Server-Pfad nicht gefunden</string>
+    <string name="sync_error_server">Server-Fehler</string>
+    <string name="sync_error_http">HTTP-Fehler: %d</string>
+    <string name="sync_error_unknown">Unbekannter Fehler</string>
+    
     <!-- ============================= -->
     <!-- URL VALIDATION ERRORS         -->
     <!-- ============================= -->
diff --git a/android/app/src/main/res/values/strings.xml b/android/app/src/main/res/values/strings.xml
@@ -93,9 +93,21 @@
     <string name="snackbar_server_error">Server error: %s</string>
     <string name="snackbar_already_synced">Already synced</string>
     <string name="snackbar_server_unreachable">Server not reachable</string>
+    <string name="snackbar_connection_timeout">Connection timeout</string>
     <string name="snackbar_synced_count">✅ Synced: %d notes</string>
     <string name="snackbar_nothing_to_sync">ℹ️ Nothing to sync</string>
     
+    <!-- ============================= -->
+    <!-- SYNC ERROR MESSAGES           -->
+    <!-- ============================= -->
+    <string name="sync_error_ssl">SSL error</string>
+    <string name="sync_error_auth_failed">Authentication failed</string>
+    <string name="sync_error_access_denied">Access denied</string>
+    <string name="sync_error_path_not_found">Server path not found</string>
+    <string name="sync_error_server">Server error</string>
+    <string name="sync_error_http">HTTP error: %d</string>
+    <string name="sync_error_unknown">Unknown error</string>
+    
     <!-- ============================= -->
     <!-- URL VALIDATION ERRORS         -->
     <!-- ============================= -->
diff --git a/fastlane/metadata/android/de-DE/changelogs/18.txt b/fastlane/metadata/android/de-DE/changelogs/18.txt
@@ -1,3 +1,4 @@
 • Behoben: App-Absturz auf Android 9 - Danke an @roughnecks
+• Behoben: Kernel-VPN-Kompatibilität (Wireguard)
 • Verbessert: Stabilität der Sync-Sessions
 • Technisch: Optimierte Verbindungsverwaltung
diff --git a/fastlane/metadata/android/en-US/changelogs/18.txt b/fastlane/metadata/android/en-US/changelogs/18.txt
