refactor(cordova/apple): simplify OutlineAppleLib

src/cordova/apple/OutlineAppleLib/Sources/OutlineTunnelSources/OutlineVpn.swift

@@ -14,6 +14,7 @@
 
 import CocoaLumberjackSwift
 import NetworkExtension
+import Tun2socks
 
 // Manages the system's VPN tunnel through the VpnExtension process.
 @objcMembers
@@ -27,7 +28,6 @@
   public private(set) var activeTunnelId: String?
   private var tunnelManager: NETunnelProviderManager?
   private var vpnStatusObserver: VpnStatusObserver?
-  private let connectivity: OutlineConnectivity
 
   private enum Action {
     static let start = "start"
@@ -68,7 +68,6 @@
   }
 
   override private init() {
-    connectivity = OutlineConnectivity()
     super.init()
     getTunnelManager() { manager in
       guard manager != nil else {
@@ -85,24 +84,21 @@
   // MARK: Interface
 
   // Starts a VPN tunnel as specified in the OutlineTunnel object.
-  public func start(_ tunnel: OutlineTunnel, _ completion: @escaping (Callback)) {
-    guard let tunnelId = tunnel.id else {
-      DDLogError("Missing tunnel ID")
-      return completion(ErrorCode.illegalServerConfiguration)
-    }
-    if isActive(tunnelId) {
+  public func start(_ tunnelId: String, configJson: [String: Any], _ completion: @escaping (Callback)) {
+    guard !isActive(tunnelId) else {
       return completion(ErrorCode.noError)
-    } else if isVpnConnected() {
-      return restartVpn(tunnelId, config: tunnel.config, completion: completion)
     }
-    self.startVpn(tunnel, isAutoConnect: false, completion)
+    if isVpnConnected() {
+      return restartVpn(tunnelId, configJson: configJson, completion: completion)
+    }
+    self.startVpn(tunnelId, configJson: configJson, isAutoConnect: false, completion)
   }
 
   // Starts the last successful VPN tunnel.
   @objc public func startLastSuccessfulTunnel(_ completion: @escaping (Callback)) {
     // Explicitly pass an empty tunnel's configuration, so the VpnExtension process retrieves
     // the last configuration from disk.
-    self.startVpn(OutlineTunnel(), isAutoConnect: true, completion)
+    self.startVpn(nil, configJson:nil, isAutoConnect: true, completion)
   }
 
   // Tears down the VPN if the tunnel with id |tunnelId| is active.
@@ -130,7 +126,8 @@
         completion(ErrorCode(rawValue: rawCode) ?? ErrorCode.serverUnreachable)
       }
     } else {
-      connectivity.isServerReachable(host: host, port: port) { isReachable in
+      DispatchQueue.global(qos: .background).async {
+        let isReachable = ShadowsocksCheckServerReachable(host, Int(port), nil)
         completion(isReachable ? ErrorCode.noError : ErrorCode.serverUnreachable)
       }
     }
@@ -151,9 +148,7 @@
 
   // MARK: Helpers
 
-  private func startVpn(
-      _ tunnel: OutlineTunnel, isAutoConnect: Bool, _ completion: @escaping(Callback)) {
-    let tunnelId = tunnel.id
+  private func startVpn(_ tunnelId: String?, configJson: [String: Any]?, isAutoConnect: Bool, _ completion: @escaping(Callback)) {
     setupVpn() { error in
       if error != nil {
         DDLogError("Failed to setup VPN: \(String(describing: error))")
@@ -163,17 +158,18 @@
       self.sendVpnExtensionMessage(message) { response in
         self.onStartVpnExtensionMessage(response, completion: completion)
       }
-      var config: [String: String]? = nil
+      var tunnelOptions: [String: Any]? = nil
       if !isAutoConnect {
-        config = tunnel.config
-        config?[MessageKey.tunnelId] = tunnelId
+        // TODO(fortuna): put this in a subkey
+        tunnelOptions = configJson
+        tunnelOptions?[MessageKey.tunnelId] = tunnelId
       } else {
         // macOS app was started by launcher.
-        config = [MessageKey.isOnDemand: "true"];
+        tunnelOptions = [MessageKey.isOnDemand: "true"];
       }
       let session = self.tunnelManager?.connection as! NETunnelProviderSession
       do {
-        try session.startTunnel(options: config)
+        try session.startTunnel(options: tunnelOptions)
       } catch let error as NSError  {
         DDLogError("Failed to start VPN: \(error)")
         completion(ErrorCode.vpnStartFailure)
@@ -189,13 +185,13 @@
   }
 
   // Sends message to extension to restart the tunnel without tearing down the VPN.
-  private func restartVpn(_ tunnelId: String, config: [String: String],
+  private func restartVpn(_ tunnelId: String, configJson: [String: Any],
                           completion: @escaping(Callback)) {
     if activeTunnelId != nil {
       vpnStatusObserver?(.disconnected, activeTunnelId!)
     }
     let message = [MessageKey.action: Action.restart, MessageKey.tunnelId: tunnelId,
-                   MessageKey.config:config] as [String : Any]
+                   MessageKey.config: configJson] as [String : Any]
     self.sendVpnExtensionMessage(message) { response in
       self.onStartVpnExtensionMessage(response, completion: completion)
     }

src/cordova/apple/OutlineAppleLib/Tests/OutlineTunnelTest/OutlineTunnelTest.swift

@@ -1,6 +1,7 @@
 import XCTest
 
 import NetworkExtension
+import Tun2socks
 
 @testable import OutlineTunnel
 @testable import PacketTunnelProvider
@@ -37,4 +38,11 @@ final class OutlineTunnelTest: XCTestCase {
 
         XCTAssertEqual(["1.1.1.1", "9.9.9.9", "208.67.222.222", "208.67.220.220"], settings.dnsSettings?.servers)
     }
+
+  func testReachability() {
+    // TODO(fortuna): run a local server instead.
+    XCTAssertTrue(ShadowsocksCheckServerReachable("8.8.8.8", 853, nil))
+    XCTAssertTrue(ShadowsocksCheckServerReachable("google.com", 443, nil))
+    XCTAssertFalse(ShadowsocksCheckServerReachable("nonexistent.getoutline.org", 443, nil))
+  }
 }

src/cordova/plugin/apple/src/OutlinePlugin.swift

@@ -76,12 +76,12 @@ class OutlinePlugin: CDVPlugin {
                        errorCode: OutlineVpn.ErrorCode.illegalServerConfiguration)
     }
     DDLogInfo("\(Action.start) \(tunnelId)")
-    guard let config = command.argument(at: 1) as? [String: Any], containsExpectedKeys(config) else {
+    // TODO(fortuna): Move the config validation to the config parsing code in Go.
+    guard let configJson = command.argument(at: 1) as? [String: Any], containsExpectedKeys(configJson) else {
       return sendError("Invalid configuration", callbackId: command.callbackId,
                        errorCode: OutlineVpn.ErrorCode.illegalServerConfiguration)
     }
-    let tunnel = OutlineTunnel(id: tunnelId, config: config)
-    OutlineVpn.shared.start(tunnel) { errorCode in
+    OutlineVpn.shared.start(tunnelId, configJson:configJson) { errorCode in
       if errorCode == OutlineVpn.ErrorCode.noError {
         #if os(macOS)
           NotificationCenter.default.post(
@@ -234,9 +234,9 @@ class OutlinePlugin: CDVPlugin {
   }
 
   // Returns whether |config| contains all the expected keys
-  private func containsExpectedKeys(_ config: [String: Any]?) -> Bool {
-    return config?["host"] != nil && config?["port"] != nil &&
-        config?["password"] != nil && config?["method"] != nil
+  private func containsExpectedKeys(_ configJson: [String: Any]?) -> Bool {
+    return configJson?["host"] != nil && configJson?["port"] != nil &&
+        configJson?["password"] != nil && configJson?["method"] != nil
   }
 
   // MARK: Callback helpers