Add IAN TCP connections

ios/MullvadRustRuntime/EphemeralPeerExchangeActor.swift

@@ -21,13 +21,9 @@ public protocol EphemeralPeerExchangeActorProtocol {
 public class EphemeralPeerExchangeActor: EphemeralPeerExchangeActorProtocol {
     struct Negotiation {
         var negotiator: EphemeralPeerNegotiating
-        var inTunnelTCPConnection: NWTCPConnection
-        var tcpConnectionObserver: NSKeyValueObservation
 
         func cancel() {
             negotiator.cancelKeyNegotiation()
-            tcpConnectionObserver.invalidate()
-            inTunnelTCPConnection.cancel()
         }
     }
 
@@ -54,15 +50,6 @@ public class EphemeralPeerExchangeActor: EphemeralPeerExchangeActorProtocol {
         self.keyExchangeRetriesIterator = iteratorProvider()
     }
 
-    private func createTCPConnection(_ gatewayEndpoint: NWHostEndpoint) -> NWTCPConnection {
-        self.packetTunnel.createTCPConnectionThroughTunnel(
-            to: gatewayEndpoint,
-            enableTLS: false,
-            tlsParameters: nil,
-            delegate: nil
-        )
-    }
-
     /// Starts a new key exchange.
     ///
     /// Any ongoing key negotiation is stopped before starting a new one.
@@ -75,49 +62,46 @@ public class EphemeralPeerExchangeActor: EphemeralPeerExchangeActorProtocol {
         endCurrentNegotiation()
         let negotiator = negotiationProvider.init()
 
-        let gatewayAddress = LocalNetworkIPs.gatewayAddress.rawValue
-        let IPv4Gateway = IPv4Address(gatewayAddress)!
-        let endpoint = NWHostEndpoint(hostname: gatewayAddress, port: "\(CONFIG_SERVICE_PORT)")
-        let inTunnelTCPConnection = createTCPConnection(endpoint)
-
         // This will become the new private key of the device
         let ephemeralSharedKey = PrivateKey()
 
         let tcpConnectionTimeout = keyExchangeRetriesIterator.next() ?? .seconds(10)
         // If the connection never becomes viable, force a reconnection after 10 seconds
-        scheduleInTunnelConnectionTimeout(startTime: .now() + tcpConnectionTimeout)
-
-        let tcpConnectionObserver = inTunnelTCPConnection.observe(\.isViable, options: [
-            .initial,
-            .new,
-        ]) { [weak self] observedConnection, _ in
-            guard let self, observedConnection.isViable else { return }
-            self.negotiation?.tcpConnectionObserver.invalidate()
-            self.timer?.cancel()
-
-            if !negotiator.startNegotiation(
-                gatewayIP: IPv4Gateway,
-                devicePublicKey: privateKey.publicKey,
-                presharedKey: ephemeralSharedKey,
-                peerReceiver: packetTunnel,
-                tcpConnection: inTunnelTCPConnection,
-                peerExchangeTimeout: tcpConnectionTimeout,
-                enablePostQuantum: enablePostQuantum,
-                enableDaita: enableDaita
-            ) {
-                // Cancel the negotiation to shut down any remaining use of the TCP connection on the Rust side
-                self.negotiation?.cancel()
-                self.negotiation = nil
-                self.onFailure()
-            }
+        let peerParameters = EphemeralPeerParameters(
+            peer_exchange_timeout: UInt64(tcpConnectionTimeout.timeInterval),
+            enable_post_quantum: enablePostQuantum,
+            enable_daita: enableDaita,
+            funcs: mapWgFunctions(functions: packetTunnel.wgFunctions())
+        )
+
+        if !negotiator.startNegotiation(
+            devicePublicKey: privateKey.publicKey,
+            presharedKey: ephemeralSharedKey,
+            peerReceiver: packetTunnel,
+            ephemeralPeerParams: peerParameters
+        ) {
+            // Cancel the negotiation to shut down any remaining use of the TCP connection on the Rust side
+            self.negotiation?.cancel()
+            self.negotiation = nil
+            self.onFailure()
         }
+
         negotiation = Negotiation(
-            negotiator: negotiator,
-            inTunnelTCPConnection: inTunnelTCPConnection,
-            tcpConnectionObserver: tcpConnectionObserver
+            negotiator: negotiator
         )
     }
 
+    private func mapWgFunctions(functions: WgFunctionPointers) -> WgTcpConnectionFunctions {
+        var mappedFunctions = WgTcpConnectionFunctions()
+
+        mappedFunctions.close_fn = functions.close
+        mappedFunctions.open_fn = functions.open
+        mappedFunctions.send_fn = functions.send
+        mappedFunctions.recv_fn = functions.receive
+
+        return mappedFunctions
+    }
+
     /// Cancels the ongoing key exchange.
     public func endCurrentNegotiation() {
         negotiation?.cancel()
@@ -129,19 +113,4 @@ public class EphemeralPeerExchangeActor: EphemeralPeerExchangeActorProtocol {
         keyExchangeRetriesIterator = iteratorProvider()
         endCurrentNegotiation()
     }
-
-    private func scheduleInTunnelConnectionTimeout(startTime: DispatchWallTime) {
-        let newTimer = DispatchSource.makeTimerSource()
-
-        newTimer.setEventHandler { [weak self] in
-            self?.onFailure()
-            self?.timer?.cancel()
-        }
-
-        newTimer.schedule(wallDeadline: startTime)
-        newTimer.activate()
-
-        timer?.cancel()
-        timer = newTimer
-    }
 }

ios/MullvadRustRuntime/EphemeralPeerNegotiator.swift

@@ -14,14 +14,10 @@ import WireGuardKitTypes
 // swiftlint:disable function_parameter_count
 public protocol EphemeralPeerNegotiating {
     func startNegotiation(
-        gatewayIP: IPv4Address,
         devicePublicKey: PublicKey,
         presharedKey: PrivateKey,
         peerReceiver: any TunnelProvider,
-        tcpConnection: NWTCPConnection,
-        peerExchangeTimeout: Duration,
-        enablePostQuantum: Bool,
-        enableDaita: Bool
+        ephemeralPeerParams: EphemeralPeerParameters
     ) -> Bool
 
     func cancelKeyNegotiation()
@@ -33,49 +29,45 @@ public protocol EphemeralPeerNegotiating {
 public class EphemeralPeerNegotiator: EphemeralPeerNegotiating {
     required public init() {}
 
-    var cancelToken: EphemeralPeerCancelToken?
+    var cancelToken: OpaquePointer?
 
     public func startNegotiation(
-        gatewayIP: IPv4Address,
         devicePublicKey: PublicKey,
         presharedKey: PrivateKey,
         peerReceiver: any TunnelProvider,
-        tcpConnection: NWTCPConnection,
-        peerExchangeTimeout: Duration,
-        enablePostQuantum: Bool,
-        enableDaita: Bool
+        ephemeralPeerParams: EphemeralPeerParameters
     ) -> Bool {
         // swiftlint:disable:next force_cast
         let ephemeralPeerReceiver = Unmanaged.passUnretained(peerReceiver as! EphemeralPeerReceiver)
             .toOpaque()
-        let opaqueConnection = Unmanaged.passUnretained(tcpConnection).toOpaque()
-        var cancelToken = EphemeralPeerCancelToken()
 
-        let result = request_ephemeral_peer(
+        guard let tunnelHandle = try? peerReceiver.tunnelHandle() else {
+            return false
+        }
+
+        let cancelToken = request_ephemeral_peer(
             devicePublicKey.rawValue.map { $0 },
             presharedKey.rawValue.map { $0 },
             ephemeralPeerReceiver,
-            opaqueConnection,
-            &cancelToken,
-            UInt64(peerExchangeTimeout.timeInterval),
-            enablePostQuantum,
-            enableDaita
+            tunnelHandle,
+            ephemeralPeerParams
         )
-        guard result == 0 else {
+        guard let cancelToken else {
             return false
         }
         self.cancelToken = cancelToken
         return true
     }
 
     public func cancelKeyNegotiation() {
-        guard var cancelToken else { return }
-        cancel_ephemeral_peer_exchange(&cancelToken)
+        guard let cancelToken else { return }
+        cancel_ephemeral_peer_exchange(cancelToken)
+        self.cancelToken = nil
     }
 
     deinit {
-        guard var cancelToken else { return }
-        drop_ephemeral_peer_exchange_token(&cancelToken)
+        guard let cancelToken else { return }
+        drop_ephemeral_peer_exchange_token(cancelToken)
     }
 }
 

ios/MullvadRustRuntime/EphemeralPeerReceiver.swift

@@ -0,0 +1,52 @@
+//
+//  EphemeralPeerReceiver.swift
+//  PacketTunnel
+//
+//  Created by Marco Nikic on 2024-02-15.
+//  Copyright © 2023 Mullvad VPN AB. All rights reserved.
+//
+
+import Foundation
+import MullvadRustRuntimeProxy
+import MullvadTypes
+import NetworkExtension
+import WireGuardKitTypes
+
+/// End sequence of an ephemeral peer exchange.
+///
+/// This FFI function is called by Rust when an ephemeral peer negotiation succeeded or failed.
+/// When both the `rawPresharedKey` and the `rawEphemeralKey` are raw pointers to 32 bytes data arrays,
+/// the quantum-secure key exchange is considered successful.
+/// If the `rawPresharedKey` is nil, but there is a valid `rawEphemeralKey`, it means a Daita peer has been negotiated with.
+/// If `rawEphemeralKey` is nil, the negotiation is considered failed.
+///
+/// - Parameters:
+///   - rawEphemeralPeerReceiver: A raw pointer to the running instance of `NEPacketTunnelProvider`
+///   - rawPresharedKey: A raw pointer to the quantum-secure pre shared key
+///   - rawEphemeralKey: A raw pointer to the ephemeral private key of the device
+@_cdecl("swift_ephemeral_peer_ready")
+func receivePostQuantumKey(
+    rawEphemeralPeerReceiver: UnsafeMutableRawPointer?,
+    rawPresharedKey: UnsafeMutableRawPointer?,
+    rawEphemeralKey: UnsafeMutableRawPointer?
+) {
+    guard let rawEphemeralPeerReceiver else { return }
+    let ephemeralPeerReceiver = Unmanaged<EphemeralPeerReceiver>.fromOpaque(rawEphemeralPeerReceiver)
+        .takeUnretainedValue()
+
+    // If there are no private keys for the ephemeral peer, then the negotiation either failed, or timed out.
+    guard let rawEphemeralKey,
+          let ephemeralKey = PrivateKey(rawValue: Data(bytes: rawEphemeralKey, count: 32)) else {
+        ephemeralPeerReceiver.ephemeralPeerExchangeFailed()
+        return
+    }
+
+    // If there is a pre-shared key, an ephemeral peer was negotiated with Post Quantum options
+    // Otherwise, a Daita enabled ephemeral peer was requested
+    if let rawPresharedKey, let key = PreSharedKey(rawValue: Data(bytes: rawPresharedKey, count: 32)) {
+        ephemeralPeerReceiver.receivePostQuantumKey(key, ephemeralKey: ephemeralKey)
+    } else {
+        ephemeralPeerReceiver.receiveEphemeralPeerPrivateKey(ephemeralKey)
+    }
+    return
+}