I've implemented a custom system extension VPN for macOS using Packet Tunnel Provider. The VPN is configured with on-demand, and a rule to always connect whenever there's traffic: onDemandRules = [NEOnDemandRuleConnect()] As expected, if the VPN isn't active, all traffic gets blocked until it is ready. Not expected: In the following scenario, there is some 'traffic leak': Use only WiFi (not wired cable) Connect the VPN Disable the WiFi and wait for the VPN to disconnect Enable the WiFi Some packets are routed outside the VPN, and aren't being blocked Some moments after, all traffic will be blocked, and the VPN will start the 'connecting' process. Is the above scenario a 'known' issue? Can it be a race condition in the OS, where some packets can be sent after the network is brought back before the VPN process starts? Is there any way to fix this problem? P.S: I'm not using flags such as 'capture all network'

[Q] Has there been a change in macOS 15.3.2 and later that can explain why some UDP traffic is not seen by some Network Extensions when it is in previous macOS minor and major versions?

Hi, I built a system that can detect and block Short Form Videos like Instagram Reels and Youtube Shorts. It works by connecting the iphone to a VPN and then do statistics on network packets (no decryption). I was wondering the feasibility of porting this to run on device. Functionality wise I would need: packet interception, packet drop, DNS query interception. I saw that Content filter providers could be something to look into, but then I read an article of how you would have to have a managed device which is not ideal for the end user. New to apple development, the lack of snippets and code examples is confusing.

In our App, we have a network extension with a NEAppPushProvider subclass running. We run the following steps Setup a dual-band wireless router per the following: Broadcasting 2.4 GHz and 5 GHz channels Same SSID names for both channels Connected to the production network to the router DHCP assigning addresses in the 10.1.x.x network Connect the mobile device to the 5 GHz network (if needed, turn off the 2.4 GHz network temporarily; once the device connects to the 5 GHz network, the 2.4 GHz network can be turned back on). Create a NEAppPushManager in the App, using the SSID from the above mentioned network and set it to the matchSSIDs property. Call saveToPreferences() on the push manager to save. A. We have UI that shows the extension has been started and it has connected to the server successfully. Walk out of the range of the 5 GHz channel of the router, but stay within range of the 2.4ghz channel. Wait for the mobile device to connect to the 2.4 GHz channel. Expected: The extension would reconnect to the 2.4ghz network. Observed: The extension does not reconnect. Checking the logs for the extension we see that the following was called in the push provider subclass. stop(with:completionHandler:) > PID: 808 | 🗒️🛑 Stopped with reason 3: "noNetworkAvailable" The expectation is that start() on the NEAppPushProvider subclass would be called. Is this an incorrect expectation? How does the NEAppPushProvider handle same network SSID roaming among various band frequencies? I looked at the documentation and did not find any settings targeting 2.4 or 5 ghz networks. Please advise on what to do.

I did watch WWDC 2019 Session 716 and understand that an active audio session is key to unlocking low‑level networking on watchOS. I’m configuring my audio session and engine as follows: private func configureAudioSession(completion: @escaping (Bool) -> Void) { let audioSession = AVAudioSession.sharedInstance() do { try audioSession.setCategory(.playAndRecord, mode: .voiceChat, options: []) try audioSession.setActive(true, options: .notifyOthersOnDeactivation) // Retrieve sample rate and configure the audio format. let sampleRate = audioSession.sampleRate print("Active hardware sample rate: \(sampleRate)") audioFormat = AVAudioFormat(standardFormatWithSampleRate: sampleRate, channels: 1) // Configure the audio engine. audioInputNode = audioEngine.inputNode audioEngine.attach(audioPlayerNode) audioEngine.connect(audioPlayerNode, to: audioEngine.mainMixerNode, format: audioFormat) try audioEngine.start() completion(true) } catch { print("Error configuring audio session: \(error.localizedDescription)") completion(false) } } private func setupUDPConnection() { let parameters = NWParameters.udp parameters.includePeerToPeer = true connection = NWConnection(host: "***.***.xxxxx.***", port: 0000, using: parameters) setupNWConnectionHandlers() } private func setupTCPConnection() { let parameters = NWParameters.tcp connection = NWConnection(host: "***.***.xxxxx.***", port: 0000, using: parameters) setupNWConnectionHandlers() } private func setupWebSocketConnection() { guard let url = URL(string: "ws://***.***.xxxxx.***:0000") else { print("Invalid WebSocket URL") return } let session = URLSession(configuration: .default) webSocketTask = session.webSocketTask(with: url) webSocketTask?.resume() print("WebSocket connection initiated") sendAudioToServer() receiveDataFromServer() sendWebSocketPing(after: 0.6) } private func setupNWConnectionHandlers() { connection?.stateUpdateHandler = { [weak self] state in DispatchQueue.main.async { switch state { case .ready: print("Connected (NWConnection)") self?.isConnected = true self?.failToConnect = false self?.receiveDataFromServer() self?.sendAudioToServer() case .waiting(let error), .failed(let error): print("Connection error: \(error.localizedDescription)") DispatchQueue.main.asyncAfter(deadline: .now() + 2) { self?.setupNetwork() } case .cancelled: print("NWConnection cancelled") self?.isConnected = false default: break } } } connection?.start(queue: .main) } I am reaching out to seek further assistance regarding the challenges I've been experiencing with establishing a UDP, TCP & web socket connection on watchOS using NWConnection for duplex audio streaming. Despite implementing the recommendations provided earlier, I am still encountering difficulties. Or duplex audio streaming not possible on apple watch?

We have an old iOS app and an old camera that connects using Wi-Fi either using an access point or Ad Hoc network, e.g., iPhone/iPad connects to the camera's Wi-Fi directly... How it works (old legacy app/system, which cannot be redesigned): Camera is configured to Ad Hoc Wi-Fi network (insecure TCP). iPhone connects to this insecure Wi-Fi. Camera uses Bonjour service to broadcast its IP address. App reads in IP address and begin to send messages to the camera using NSMutableURLRequest, etc. All this works fine for iOS 17. But in iOS 18 step 4 stopped working. App simply doesn't get any responses! We believe we have configured ATS properly (App Store version): In panic we have also tried this in Test Flight version: The latter actually seemed to make a difference when running the app on macOS Apple Silicon. But on iOS it didn't seem to make any difference. Occasionally, I was lucky to get connection on on iPhone 16 Pro with iOS 18. But for the 'many' iPads I have tried I couldn't. I also tried to install CFNetwork profile and look at the logs but I believe I just got timeout on the requests. Questions: Why it iOS 18 different? Bonjour works fine, but NSSURLRequests doesn't Do we configure ATS correctly for this scenario? What should I look for in the Console log when CFNetwork profile is installed? Should I file a TSI? Thanks! :)

When i try to set the value ‘false’ for ‘usesClassicLoadingMode’ it is getting crashed. The crash logs has been shared below Ex: let config = URLSessionConfiguration.default if #available(iOS 18.4, *) { config.usesClassicLoadingMode = false } Error log : *** Terminating app due to uncaught exception 'NSInvalidArgumentException', reason: '-[__NSCFBoolean objectForKeyedSubscript:]: unrecognized selector sent to instance 0x1f655c390' *** First throw call stack: (0x188ae52ec 0x185f69a7c 0x188b4f67c 0x1889fcb84 0x1889fc4f0 0x191393bc8 0x1889ec8a0 0x1889ec6e4 0x191393ad0 0x191344dac 0x191344b58 0x107cfa064 0x107ce36d0 0x191343fcc 0x1891b3b18 0x1892dae58 0x189235c60 0x18921e270 0x18921d77c 0x18921a8ac 0x107ce0584 0x107cfa064 0x107ce891c 0x107ce95d8 0x107ceabcc 0x107cf5894 0x107cf4eb0 0x212f51660 0x212f4e9f8) terminating due to uncaught exception of type NSException Can you please provider the resolution steps

Hi, Our project is a MacOS SwiftUI GUI application that bundles a System Network Extension, signed with a Developer ID certificate for distribution outside of the app store. The system network extension is used to write a packet tunnel provider. The signing of the app & network extension is handled by XCode (v16.0.0), we do not run codesign ourselves. We have no issues with XPC or the system network extension during normal usage, nor when the application is installed on a user's device for the first time. The problem only arises when the user upgrades the application. I have experienced this issue myself, as have our users. It's been reported on Apple Silicon macbooks running at least macOS 15.3.2. Much like the SimpleFirewall example (which we used as a reference), we use XPC for basic communication of state between the app and NE. These XPC connections stop working when the user installs a new version of the app, with OS logs from the process indicating that the connection is immediately invalidated. Subsequent connection attempts are also immediately invalidated. Toggling the VPN in system settings (or via the app) does not resolve the problem, nor does restarting the app, nor does deleting and reinstalling the app, nor does restarting the device. The only reliable workaround is to delete the system extension in Login Items & Extensions, under Network Extensions. No device restart is necessary to garbage collect the old extension - once the extension is reapproved by the user, the XPC issue resolves itself. This would be an acceptable workaround were it possible to automate the deleting of the system extension, but that appears deliberately not possible, and requiring our users to do this each time they update is unreasonable. When the upgraded app is opened for the first time, the OSSystemExtensionRequest request is sent, and the outcome is that the previously installed system network extension is replaced, as both the CFBundleVersion and CFBundleShortVersionString differ. When this issue is encountered, the output of systemextensionsctl list shows the later version is installed and activated. I've been able to reproduce this bug on my personal laptop, with SIP on and systemextensionsctl developer off, but on my work laptop with SIP off and systemextensionsctl developer on (where the network extension is replaced on each activation request, instead of only when the version strings differ), I do not encounter this issue, which leads me to believe it has something to do with the notarization process. We notarize the pkg using xcrun notarytool, and then staple to the pkg. This is actually the same issue described in: https://developer.apple.com/forums/thread/711713 https://developer.apple.com/forums/thread/667597 https://developer.apple.com/forums/thread/742992 https://developer.apple.com/forums/thread/728063 but it's been a while since any of these threads were updated, and we've made attempts to address it off the suggestions in the threads to no avail. Those suggestions are: Switching to a .pkg installer from a .dmg As part of the .pkg preinstall, doing all of the following: Stopping the VPN (scutil --nc stop), shutting down the app (using osascript 'quit app id'), and deleting the app (which claims to delete the network extension, but not the approval in Login Items & Extensions remains??), by running rm -rf on the bundle in /Applications As part of the .pkg postinstall: Forcing macOS to ingest the App bundle's notarization ticket using spctl --assess. Ensuring NSXPCListener.resume() is called after autoreleasepool { NEProvider.startSystemExtensionMode() } (mentioned in a forum thread above as a fix, did not help.) One thing I'm particularly interested in is the outcome of this feedback assistant ticket, as I can't view it: FB11086599. It was shared on this forum in the first thread above, and supposedly describes the same issue. I almost find it hard to believe that this issue has been around for this many years without a workaround (there's system network extension apps out there that appear to work fine when updating, are they not using XPC?), so I wonder if there's a fix described in that FB ticket. Since I can't view that above feedback ticket, I've created my own: FB17032197

when i set the flag false to the usesClassicLoadingMode, then the application is getting crashed Ex: let config = URLSessionConfiguration.default if #available(iOS 18.4, *) { config.usesClassicLoadingMode = false } Crash log : *** Terminating app due to uncaught exception 'NSInvalidArgumentException', reason: '-[__NSCFBoolean objectForKeyedSubscript:]: unrecognized selector sent to instance 0x1f655c390' *** First throw call stack: (0x188ae52ec 0x185f69a7c 0x188b4f67c 0x1889fcb84 0x1889fc4f0 0x191393bc8 0x1889ec8a0 0x1889ec6e4 0x191393ad0 0x191344dac 0x191344b58 0x107cfa064 0x107ce36d0 0x191343fcc 0x1891b3b18 0x1892dae58 0x189235c60 0x18921e270 0x18921d77c 0x18921a8ac 0x107ce0584 0x107cfa064 0x107ce891c 0x107ce95d8 0x107ceabcc 0x107cf5894 0x107cf4eb0 0x212f51660 0x212f4e9f8) terminating due to uncaught exception of type NSException

I don't understand what permissions need to be given for this code to operate. I cannot seem to work out why I'm not able to see a BSSID. I think I've given sandbox the appropriate permissions AND I've added some to the Target Properties for good measure. Yet, cannot get BSSID. import SwiftUI import CoreWLAN import CoreLocation struct ContentView: View { @State private var currentBSSID: String = "Loading..." var body: some View { VStack { Image(systemName: "globe") .imageScale(.large) .foregroundStyle(.tint) Text("Current BSSID:") Text(currentBSSID) } .padding() .onAppear(perform: fetchBSSID) } func fetchBSSID() { if let iface2 = CWWiFiClient.shared().interface() { print("✅ Found Wi-Fi interface: \(iface2.interfaceName ?? "nil")") } else { print("❌ No Wi-Fi interface found") } if let iface = CWWiFiClient.shared().interface(), let bssid = iface.bssid() { currentBSSID = bssid } else { currentBSSID = "Not connected" print("✅ BSSID: \(currentBSSID)") } } } #Preview { ContentView() } Output - WifI interface is found but BSSID is not found.

I am making a USB attached IoT device that follows the Matter approach to connectivity (IP/mDNS/DHCP). I am having conflicts with it as it appears to MacOS as an Ethernet adapter and this is causing it to be assigned as a "default" route, interfering with routing when my Mac is connected to NAT based WiFi. I'd like to be able to hint to MacOS & iPadOS that this is not a routable private network, the subnet should be respected and a default route should not be assigned to it, otherwise the order of the device connection is used by the IP routing tables and I am concerned my non-routable private network will initialize before Wifi and block NAT based internet connectivity. How can I hint to MacOS/iPadOS "this is not a routable private network, this is not a NAT, do not assign me a default route beyond the subnet I have provided you."

Hi there! We are working on our SkyElectric App which is being developed in Flutter framework, where we need user to connect with the Wifi of the the inverter. We are trying to direct user to WiFi Settings page of the iOS in general settings where all the available WiFi Networks are listed but unfortunately user is being directed to App's Settings page. We are using package of app_settings and launcher. I've read that Apple changed a policy in 2019 where it restricts Apps to navigate to OS pages. Question: Could you please verify if I APPLE allows us to access the General Settings or WiFi Settings through clicking a button in our App name "Open WiFi Settings", If not then Why?

I am trying to make http3 client with Network.framework on Apple platforms. Codes that implement NWConnectionGroup.start with NWListener don't always work with warning below. I assume NWConnectionGroup.newConnectionHandler or NWListener.newConnectionHandler will be called to start connection from the server if it works. nw_protocol_instance_add_new_flow [C1.1.1:2] No listener registered, cannot accept new flow quic_stream_add_new_flow [C1.1.1:2] [-fde1594b83caa9b7] failed to create new stream for received stream id 3 so I tried: create the NWListener -> not work check whether NWConnectionGroup has a member to register or not NWListener -> not work (it doesn't have). use NWConnection instead of NWConnectionGroup -> not work Is my understanding correct? How should I do to set or associate listener with NWConnection/Group for newConnectionHandler is called and to delete wanings? What is the best practice in the case? Sample codes are below. Thanks in advance. // http3 needs unidirectional stream by the server and client. // listener private let _listener: NWListener let option: NWProtocolQUIC.Options = .init(alpn:["h3"]) let param: NWParameters = .init(quic: option) _listener = try! .init(using: param) _listener.stateUpdateHandler = { state in print("listener state: \(state)") } _listener.newConnectionHandler = { newConnection in print("new connection added") } _listener.serviceRegistrationUpdateHandler = { registrationState in print("connection registrationstate") } // create connection private let _group: NWConnectionGroup let options: NWProtocolQUIC.Options = .init(alpn: ["h3"]) options.direction = .unidirectional options.isDatagram = false options.maxDatagramFrameSize = 65535 sec_protocol_options_set_verify_block(options.securityProtocolOptions, {(_: sec_protocol_metadata_t, _: sec_trust_t, completion: @escaping sec_protocol_verify_complete_t) in print("cert completion.") completion(true) }, .global()) let params: NWParameters = .init(quic: options) let group: NWMultiplexGroup = .init( to: .hostPort(host: NWEndpoint.Host("google.com"), port: NWEndpoint.Port(String(443))!)) _group = .init(with: group, using: params) _group.setReceiveHandler {message,content,isComplete in print("receive: \(message)") } _group.newConnectionHandler = {newConnection in print("newConnectionHandler: \(newConnection.state)") } _group.stateUpdateHandler = { state in print("state: \(state)") } _group.start(queue: .global()) _listener.start(queue: .global()) if let conn = _group.extract() { let data: Data = .init() let _ = _group.reinsert(connection: conn) conn.send(content: data, completion: .idempotent) }

Hello! 👋 I am noticing new failures in the iOS 18.5 Developer Beta build (22EF5042g) when calling the system call connect() (from C++ source, in network extension). When using cell/mobile data (Mint & T-Mobile) this returns with EINTR (interrupted system call) right away. When I switch over to wifi, everything works fine. Note: I have not tested on other mobile carriers; which could make a difference since T-Mobile/Mint are IPv6 networks. FWIW, this is working in the previous developer beta (18.4). Anyone have any ideas?

On an iOS 18 device, after installing the application and initially denying local network permission when prompted, manually enabling this permission in the system settings does not resolve the issue. After uninstalling and reinstalling the app, although local network access is granted, the app cannot discover smart hardware devices over the local area network (LAN) or proceed with configuration. The smart hardware sends configuration data packets over the LAN, but the app fails to receive these packets. This issue persists even after another uninstall and reinstall of the app. However, rebooting the device restores normal functionality. Steps to Reproduce: Install the application on an iOS 18 device. Upon first launch, deny the request for local network permissions. Manually enable local network permissions via "Settings" > [App Name]. Uninstall and then reinstall the application. Attempt to discover and configure smart hardware devices using the app. Notice that the app fails to receive configuration data packets sent by the smart hardware over the LAN. Expected Result: The application should be able to normally receive configuration data packets from smart hardware devices over the LAN and successfully complete the configuration process after obtaining local network permissions. Actual Result: Even after being granted local network permissions, the application cannot discover devices or receive configuration data packets over the LAN unless the iPhone device is rebooted. (reinstall app and obtaining local network permissions is not work too.)

Hello, Recently I am trying to add stub dns server to my Network Extension (a VPN app), after some research on this forum, and since my language is C, I have the following plan: create a udp socket which use setsockopt(IP_BOUND_IF) to bound the socket to the utun if index obtained, and also bind to the address of the utun address I set(let's say 192.168.99.2), then listen on the udp port 53 which is ready to handle dns request. configure the dns server to 192.168.99.2 in the provider's Network Settings, thus iOS system will send udp query to the udp socket created in step 1, and it can then do some split dns function such as resolve using local interface (cellular or wifi), or some nameserve which will be routed to the VPN tunnel (will create new UDP socket and do IP_BOUND_IF to ensure the traffic will enter the VPN tunnel), and the result should be return to the system and then the non VPP apps. But I observer weird issue, indeed I can get the system send the dns request to the listening udp socket and I can get the result write to the system(address like 192.168.99.2:56144, the port should be allocated by the iOS system's DNS component) without any failure(I did get some error before due to I using the wrong utun if index, but fixed it later), but it seems non VPN app like browser can't get the resolved ip for domains. I want to ask is this limited by the sandbox? or any special sock opt I need to do. Thanks. PS: in the provider's network settings, all the system's traffic will be point to the utun, which means the VPN process will process all the traffic. the reason I do not set the dns server to utun peers side which is my userspace networking stack's ip (192.168.99.1) is the stack is not be able to leverage some dns libraries due to architecture issue. (it's fd.io vpp which we ported to apple platform).

We are currently working on a zero-configuration networking compliant device thru avahi-daemon. Our Device want to have multiple Instance name for different services. Example InstanceA._ipps._tcp.local. InstanceA._ipp._tcp.local. InstanceB._ipps._tcp.local. InstanceB._ipp._tcp.local. Will BCT confuse this as multiple device connected in the network and cause it to fail? Does Bonjour only allows only a Single Instance name with multiple services?

I'm establishing a connection with NWListener and NWConnection which is working great. However, if the listener disappears, a lot of logs are appearing: Is there a way to hide these logs? I'm aware of OS_ACTIVITY_MODE=disabled, but that will also hide a lot of other logs. I also know you can hide these using Xcode's filtering. I'm looking for a programmatically way to hide these completely. I'm not interested in seeing these at all, or, at least, I want to be in control. Thanks!

Our enterprise product uses a content filter, normally customers deploy MDM profiles to authorise and allow the content filter to work. Some customers however do not use these profiles, requiring them to enable the system extension in System Settings and allow the content filter via the popup below. If the user selects "Don't Allow", intentionally or by mistake, there does not appear to be an mechanism for them to change their mind and allow it instead. If the user fails to enable the system extension on the first prompt, there is an option to enable if via System Settings. There doesn't seem to be a similar option if they "Don't Allow" the content filter. How can the user allow a previously denied content filter?

I am seeking assistance with how to properly handle / save / reuse NWConnections when it comes to the NWBrowser vs NWListener. Let me give some context surrounding why I am trying to do what I am. I am building an iOS app that has peer to peer functionality. The design is for a user (for our example the user is Bob) to have N number of devices that have my app installed on it. All these devices are near each other or on the same wifi network. As such I want all the devices to be able to discover each other and automatically connect to each other. For example if Bob had three devices (A, B, C) then A discovers B and C and has a connection to each, B discovers B and C and has a connection to each and finally C discovers A and B and has a connection to each. In the app there is a concept of a leader and a follower. A leader device issues commands to the follower devices. A follower device just waits for commands. For our example device A is the leader and devices B and C are followers. Any follower device can opt to become a leader. So if Bob taps the “become leader” button on device B - device B sends out a message to all the devices it’s connected to telling them it is becoming the new leader. Device B doesn’t need to do anything but device A needs to set itself as a follower. This detail is to show my need to have everyone connected to everyone. Please note that I am using .includePeerToPeer = true in my NWParameters. I am using http/3 and QUIC. I am using P12 identity for TLS1.3. I am successfully able to verify certs in sec_protocal_options_set_verify_block. I am able to establish connections - both from the NWBrowser and from NWListener. My issue is that it’s flaky. I found that I have to put a 3 second delay prior to establishing a connection to a peer found by the NWBrowser. I also opted to not save the incoming connection from NWListener. I only save the connection I created from the peer I found in NWBrowser. For this example there is Device X and Device Y. Device X discovers device Y and connects to it and saves the connection. Device Y discovers device X and connects to it and saves the connection. When things work they work great - I am able to send messages back and forth. Device X uses the saved connection to send a message to device Y and device Y uses the saved connection to send a message to device X. Now here come the questions. Do I save the connection I create from the peer I discovered from the NWBrowser? Do I save the connection I get from my NWListener via newConnectionHandler? And when I save a connection (be it from NWBrowser or NWListener) am I able to reuse it to send data over (ie “i am the new leader command”)? When my NWBrowser discovers a peer, should I be able to build a connection and connect to it immediately? I know if I save the connection I create from the peer I discover I am able to send messages with it. I know if I save the connection from NWListener - I am NOT able to send messages with it — but should I be able to? I have a deterministic algorithm for who makes a connection to who. Each device has an ID - it is a UUID I generate when the app loads - I store it in UserDefaults and the next time I try and fetch it so I’m not generating new UUIDs all the time. I set this deviceID as the name of the NWListener.Service I create. As a result the peer a NWBrowser discovers has the deviceID set as its name. Due to this the NWBrowser is able to determine if it should try and connect to the peer or if it should not because the discovered peer is going to try and connect to it. So the algorithm above would be great if I could save and use the connection from NWListener to send messages over.