tor fusion service

lib/services/fusion_tor_service.dart

@@ -0,0 +1,71 @@
+import 'dart:io';
+
+import 'package:stackwallet/utilities/logger.dart';
+import 'package:tor_ffi_plugin/tor_ffi_plugin.dart';
+
+class FusionTorService {
+  Tor? _tor;
+  String? _torDataDirPath;
+
+  TorStatus get status => _tor!.status;
+
+  /// Singleton instance of the TorService.
+  ///
+  /// Use this to access the TorService and its properties.
+  static final sharedInstance = FusionTorService._();
+
+  // private constructor for singleton
+  FusionTorService._();
+
+  /// Getter for the proxyInfo.
+  ///
+  /// Throws if Tor is not connected.
+  ({
+    InternetAddress host,
+    int port,
+  }) getProxyInfo() {
+    try {
+      return (
+        host: InternetAddress.loopbackIPv4,
+        port: _tor!.port,
+      );
+    } catch (_) {
+      throw Exception("Tor proxy info fetched while not connected!");
+    }
+  }
+
+  /// Initialize the tor ffi lib instance if it hasn't already been set. Nothing
+  /// changes if _tor is already been set.
+  void init({
+    required String torDataDirPath,
+    Tor? mockableOverride,
+  }) {
+    _tor ??= mockableOverride ?? Tor.instance;
+    _torDataDirPath ??= torDataDirPath;
+  }
+
+  /// Start the Tor service.
+  ///
+  /// This will start the Tor service and establish a Tor circuit.
+  ///
+  /// Throws an exception if the Tor library was not inited or if the Tor
+  /// service fails to start.
+  ///
+  /// Returns a Future that completes when the Tor service has started.
+  Future<void> start() async {
+    if (_tor == null || _torDataDirPath == null) {
+      throw Exception("FusionTorService.init has not been called!");
+    }
+
+    // Start the Tor service.
+    try {
+      await _tor!.start(torDataDirPath: _torDataDirPath!);
+    } catch (e, s) {
+      Logging.instance.log(
+        "FusionTorService.start failed: $e\n$s",
+        level: LogLevel.Warning,
+      );
+      rethrow;
+    }
+  }
+}

lib/services/mixins/fusion_wallet_interface.dart

@@ -12,7 +12,7 @@ import 'package:isar/isar.dart';
 import 'package:stackwallet/db/isar/main_db.dart';
 import 'package:stackwallet/electrumx_rpc/cached_electrumx.dart';
 import 'package:stackwallet/models/isar/models/isar_models.dart';
-import 'package:stackwallet/services/tor_service.dart';
+import 'package:stackwallet/services/fusion_tor_service.dart';
 import 'package:stackwallet/utilities/amount/amount.dart';
 import 'package:stackwallet/utilities/enums/coin_enum.dart';
 import 'package:stackwallet/utilities/enums/derive_path_type_enum.dart';
@@ -28,7 +28,7 @@ mixin FusionWalletInterface {
   late final Coin _coin;
   late final MainDB _db;
   late final CachedElectrumX _cachedElectrumX;
-  late final TorService _torService;
+  late final FusionTorService _torService;
 
   // Passed in wallet functions.
   late final Future<Address> Function(
@@ -58,25 +58,8 @@ mixin FusionWalletInterface {
     _coin = coin;
     _db = db;
     _generateAddressForChain = generateAddressForChain;
-    _torService = TorService.sharedInstance;
+    _torService = FusionTorService.sharedInstance;
     _cachedElectrumX = cachedElectrumX;
-
-    // Try getting the proxy info.
-    //
-    // Start the Tor service if it's not already running.  Returns if Tor is already
-    // connected or else after Tor returns from start().
-    try {
-      _torService.getProxyInfo();
-      // Proxy info successfully retrieved, Tor is connected.
-      return;
-    } catch (e) {
-      // Init the Tor service if it hasn't already been.
-      final torDir = await StackFileSystem.applicationTorDirectory();
-      _torService.init(torDataDirPath: torDir.path);
-
-      // Start the Tor service.
-      return await _torService.start();
-    }
   }
 
   /// Returns a list of all addresses in the wallet.
@@ -198,20 +181,38 @@ mixin FusionWalletInterface {
     return unusedAddresses;
   }
 
+  int _torStartCount = 0;
+
   /// Returns the current Tor proxy address.
   Future<({InternetAddress host, int port})> getSocksProxyAddress() async {
-    /*
-    // Start the Tor service if it's not already running.
-    if (_torService.proxyInfo.port == -1) { // -1 indicates that the proxy is not running.
-      await _torService.start(); // We already unawaited this in initFusionInterface...
+    if (_torStartCount > 5) {
+      // something is quite broken so stop trying to recursively fetch
+      // start up tor and fetch proxy info
+      throw Exception(
+        "Fusion interface attempted to start tor $_torStartCount times and failed!",
+      );
     }
-     */
 
-    // TODO make sure we've properly awaited the Tor service starting before
-    // returning the proxy address.
+    try {
+      final info = _torService.getProxyInfo();
 
-    // Return the proxy address.
-    return _torService.getProxyInfo();
+      // reset counter before return info;
+      _torStartCount = 0;
+
+      return info;
+    } catch (_) {
+      // tor is probably not running so lets fix that
+      final torDir = await StackFileSystem.applicationTorDirectory();
+      _torService.init(torDataDirPath: torDir.path);
+
+      // increment start attempt count
+      _torStartCount++;
+
+      await _torService.start();
+
+      // try again to fetch proxy info
+      return await getSocksProxyAddress();
+    }
   }
 
   // Initial attempt for CashFusion integration goes here.