Add shadowsocks-proxy crate

5 files changed, 127 insertions, 15 deletions

diff --git a/ios/MullvadVPN/AppDelegate.swift b/ios/MullvadVPN/AppDelegate.swift
index 26ac51cccf..69af7faa45 100644
--- a/ios/MullvadVPN/AppDelegate.swift
+++ b/ios/MullvadVPN/AppDelegate.swift
@@ -59,9 +59,7 @@ class AppDelegate: UIResponder, UIApplicationDelegate, UNUserNotificationCenterD
         )
 
         proxyFactory = REST.ProxyFactory.makeProxyFactory(
-            transportProvider: { [weak self] in
-                return self?.transportMonitor.transport
-            },
+            transportProvider: { [weak self] in self?.transportMonitor },
             addressCache: addressCache
         )
 
@@ -70,6 +68,7 @@ class AppDelegate: UIResponder, UIApplicationDelegate, UNUserNotificationCenterD
         devicesProxy = proxyFactory.createDevicesProxy()
 
         relayCacheTracker = RelayCacheTracker(application: application, apiProxy: apiProxy)
+
         addressCacheTracker = AddressCacheTracker(
             application: application,
             apiProxy: apiProxy,
@@ -93,7 +92,11 @@ class AppDelegate: UIResponder, UIApplicationDelegate, UNUserNotificationCenterD
             accountsProxy: accountsProxy
         )
 
-        transportMonitor = TransportMonitor(tunnelManager: tunnelManager, tunnelStore: tunnelStore)
+        transportMonitor = TransportMonitor(
+            tunnelManager: tunnelManager,
+            tunnelStore: tunnelStore,
+            relayCacheTracker: relayCacheTracker
+        )
 
         #if targetEnvironment(simulator)
         // Configure mock tunnel provider on simulator
diff --git a/ios/MullvadVPN/SimulatorTunnelProvider/SimulatorTunnelProviderHost.swift b/ios/MullvadVPN/SimulatorTunnelProvider/SimulatorTunnelProviderHost.swift
index 7d2331b92d..2078646be2 100644
--- a/ios/MullvadVPN/SimulatorTunnelProvider/SimulatorTunnelProviderHost.swift
+++ b/ios/MullvadVPN/SimulatorTunnelProvider/SimulatorTunnelProviderHost.swift
@@ -21,15 +21,22 @@ final class SimulatorTunnelProviderHost: SimulatorTunnelProviderDelegate {
     private var selectorResult: RelaySelectorResult?
     private let urlRequestProxy: URLRequestProxy
     private let relayCacheTracker: RelayCacheTracker
+    private let simulatorTransportProvider: SimulatorTunnelTransportProvider
 
     private let providerLogger = Logger(label: "SimulatorTunnelProviderHost")
     private let dispatchQueue = DispatchQueue(label: "SimulatorTunnelProviderHostQueue")
 
     init(relayCacheTracker: RelayCacheTracker) {
         self.relayCacheTracker = relayCacheTracker
+
+        let urlSession = REST.makeURLSession()
+        let urlSessionTransport = REST.URLSessionTransport(urlSession: urlSession)
+        let simulatorTransportProvider = SimulatorTunnelTransportProvider(urlSessionTransport: urlSessionTransport)
+        self.simulatorTransportProvider = simulatorTransportProvider
+
         self.urlRequestProxy = URLRequestProxy(
-            urlSession: REST.makeURLSession(),
-            dispatchQueue: dispatchQueue
+            dispatchQueue: dispatchQueue,
+            transportProvider: { simulatorTransportProvider }
         )
     }
 
diff --git a/ios/MullvadVPN/SimulatorTunnelProvider/SimulatorTunnelTransportProvider.swift b/ios/MullvadVPN/SimulatorTunnelProvider/SimulatorTunnelTransportProvider.swift
new file mode 100644
index 0000000000..a571101e3f
--- /dev/null
+++ b/ios/MullvadVPN/SimulatorTunnelProvider/SimulatorTunnelTransportProvider.swift
@@ -0,0 +1,26 @@
+//
+//  SimulatorTunnelTransportProvider.swift
+//  MullvadVPN
+//
+//  Created by Marco Nikic on 2023-05-10.
+//  Copyright © 2023 Mullvad VPN AB. All rights reserved.
+//
+
+import Foundation
+import MullvadREST
+
+final class SimulatorTunnelTransportProvider: RESTTransportProvider {
+    private let urlSessionTransport: REST.URLSessionTransport
+
+    init(urlSessionTransport: REST.URLSessionTransport) {
+        self.urlSessionTransport = urlSessionTransport
+    }
+
+    func transport() -> MullvadREST.RESTTransport? {
+        urlSessionTransport
+    }
+
+    func shadowSocksTransport() -> MullvadREST.RESTTransport? {
+        urlSessionTransport
+    }
+}
diff --git a/ios/MullvadVPN/TransportMonitor/PacketTunnelTransport.swift b/ios/MullvadVPN/TransportMonitor/PacketTunnelTransport.swift
index 4ee628751d..3314fc3823 100644
--- a/ios/MullvadVPN/TransportMonitor/PacketTunnelTransport.swift
+++ b/ios/MullvadVPN/TransportMonitor/PacketTunnelTransport.swift
@@ -18,16 +18,28 @@ struct PacketTunnelTransport: RESTTransport {
     }
 
     let tunnel: Tunnel
+    let useShadowsocksTransport: Bool
 
-    init(tunnel: Tunnel) {
+    init(tunnel: Tunnel, useShadowsocksTransport: Bool) {
         self.tunnel = tunnel
+        self.useShadowsocksTransport = useShadowsocksTransport
     }
 
     func sendRequest(
         _ request: URLRequest,
         completion: @escaping (Data?, URLResponse?, Error?) -> Void
-    ) throws -> Cancellable {
-        let proxyRequest = try ProxyURLRequest(id: UUID(), urlRequest: request)
+    ) -> Cancellable {
+        let proxyRequest = ProxyURLRequest(
+            id: UUID(),
+            urlRequest: request,
+            useShadowsocksTransport: useShadowsocksTransport
+        )
+
+        // If the URL provided to the proxy request was invalid, indicate failure via `.badURL` and return a no-op.
+        guard let proxyRequest = proxyRequest else {
+            completion(nil, nil, URLError(.badURL))
+            return AnyCancellable {}
+        }
 
         return tunnel.sendRequest(proxyRequest) { result in
             switch result {
diff --git a/ios/MullvadVPN/TransportMonitor/TransportMonitor.swift b/ios/MullvadVPN/TransportMonitor/TransportMonitor.swift
index 9f02429348..e37c416682 100644
--- a/ios/MullvadVPN/TransportMonitor/TransportMonitor.swift
+++ b/ios/MullvadVPN/TransportMonitor/TransportMonitor.swift
@@ -7,21 +7,83 @@
 //
 
 import Foundation
+import MullvadLogging
 import MullvadREST
+import RelayCache
+import RelaySelector
 
-final class TransportMonitor {
+final class TransportMonitor: RESTTransportProvider {
     private let tunnelManager: TunnelManager
     private let tunnelStore: TunnelStore
     private let urlSessionTransport: REST.URLSessionTransport
+    private let relayCacheTracker: RelayCacheTracker
+    private let logger = Logger(label: "TransportMonitor")
 
-    init(tunnelManager: TunnelManager, tunnelStore: TunnelStore) {
+    // MARK: -
+
+    // MARK: Public API
+
+    init(tunnelManager: TunnelManager, tunnelStore: TunnelStore, relayCacheTracker: RelayCacheTracker) {
         self.tunnelManager = tunnelManager
         self.tunnelStore = tunnelStore
+        self.relayCacheTracker = relayCacheTracker
 
         urlSessionTransport = REST.URLSessionTransport(urlSession: REST.makeURLSession())
     }
 
-    var transport: RESTTransport? {
+    public func transport() -> MullvadREST.RESTTransport? {
+        return selectTransport(urlSessionTransport, useShadowsocksTransport: false)
+    }
+
+    public func shadowSocksTransport() -> RESTTransport? {
+        let shadowSocksTransport: RESTTransport
+        do {
+            let cachedRelays = try relayCacheTracker.getCachedRelays()
+
+            let shadowSocksConfiguration = RelaySelector.getShadowsocksTCPBridge(relays: cachedRelays.relays)
+            let shadowSocksBridgeRelay = RelaySelector.getShadowSocksRelay(relays: cachedRelays.relays)
+
+            guard let shadowSocksConfiguration = shadowSocksConfiguration,
+                  let shadowSocksBridgeRelay = shadowSocksBridgeRelay
+            else {
+                logger.error("Could not get shadow socks bridge information.")
+                return nil
+            }
+
+            let shadowSocksURLSession = urlSessionTransport.urlSession
+            let transport = REST.URLSessionShadowSocksTransport(
+                urlSession: shadowSocksURLSession,
+                shadowSocksConfiguration: shadowSocksConfiguration,
+                shadowSocksBridgeRelay: shadowSocksBridgeRelay
+            )
+
+            shadowSocksTransport = transport
+        } catch {
+            logger.error(
+                error: error,
+                message: "Could not create shadow socks transport."
+            )
+            return nil
+        }
+        return selectTransport(shadowSocksTransport, useShadowsocksTransport: true)
+    }
+
+    // MARK: -
+
+    // MARK: Private API
+
+    /// Selects a transport to use for sending an `URLRequest`
+    ///
+    /// This method returns the appropriate transport layer based on whether a tunnel is available, and whether it
+    /// should be bypassed
+    /// whenever a transport is requested.
+    ///
+    /// - Parameters:
+    ///   - transport: The transport to use if there is no tunnel, or if it shouldn't be bypassed
+    ///   - useShadowsocksTransport: A hint for enforcing a Shadowsocks transport when proxying a request via an
+    /// available `Tunnel`
+    /// - Returns: A transport to use for sending an `URLRequest`
+    private func selectTransport(_ transport: RESTTransport, useShadowsocksTransport: Bool) -> RESTTransport {
         let tunnel = tunnelStore.getPersistentTunnels().first { tunnel in
             return tunnel.status == .connecting ||
                 tunnel.status == .reasserting ||
@@ -29,10 +91,12 @@ final class TransportMonitor {
         }
 
         if let tunnel = tunnel, shouldByPassVPN(tunnel: tunnel) {
-            return PacketTunnelTransport(tunnel: tunnel)
-        } else {
-            return urlSessionTransport
+            return PacketTunnelTransport(
+                tunnel: tunnel,
+                useShadowsocksTransport: useShadowsocksTransport
+            )
         }
+        return transport
     }
 
     private func shouldByPassVPN(tunnel: Tunnel) -> Bool {