Hi, I saw that almost each OS version, on ios and macos, handles differently changing includeAllNetworks while the tunnel is running. On some the entire OS reports no-net, while others, specially latest versions, handle this fine. Can includeAllNetworks be changed while the tunnel is running, or the tunnel must be stopped and restarted with the new value? e.g. the tunnel is started with it set to false, but later is changed to true into VPN profile. And on the same note, regarding setTunnelNetworkSettings, can this be called multiple times while the tunnel is running? For example if the VPN server IP changes. Because what I've saw each call to setTunnelNetworkSettings after VPN connected results in at least DNS leaks, because the routing table is recreated. Let me know if it is easier to track to create separate questions. Thanks

We are developers of an app, we found that there's no LN prompt for users to install the app for the 1st time on ios18. We used the following method to prompt the "allow/not allow" alert: // Attempts to trigger the local network privacy alert. /// /// This builds a list of link-local IPv6 addresses and then creates a connected /// UDP socket to each in turn. Connecting a UDP socket triggers the local /// network alert without actually sending any traffic. /// /// This is a ‘best effort’ approach, and it handles errors by ignoring them. /// There’s no guarantee that it’ll actually trigger the alert (FB8711182). func triggerLocalNetworkPrivacyAlert() { let addresses = selectedLinkLocalIPv6Addresses() for address in addresses { let sock6 = socket(AF_INET6, SOCK_DGRAM, 0) guard sock6 >= 0 else { return } defer { close(sock6) } withUnsafePointer(to: address) { sa6 in sa6.withMemoryRebound(to: sockaddr.self, capacity: 1) { sa in _ = connect(sock6, sa, socklen_t(sa.pointee.sa_len)) >= 0 } } } }

Hi everyone, I'm currently working on a project where I need to send multicast packets across all available network interfaces using Apple Network Framework's NWConnectionGroup. Specifically, the MacBook (device I am using for sending multicast requests, MacOS: 15.1) is connected to two networks: Wi-Fi (Network 1) and Ethernet (Network 2), and I need to send multicast requests over both interfaces. I tried using the .requiredInterface property as suggested by Eskimo in this post, but I’m running into issues. It seems like I can't create an NWInterface object because it doesn't have any initializers. Here is the code which I wrote: var multicast_group_descriptor : NWMulticastGroup var multicast_endpoint : NWEndpoint multicast_endpoint = NWEndpoint.hostPort(host: NWEndpoint.Host("234.0.0.1"), port: NWEndpoint.Port(rawValue: 49154)!) var connection_group : NWConnectionGroup var multicast_params : NWParameters multicast_params = NWParameters.udp var interface = NWInterface(NWInterface.InterfaceType.wiredEthernet) I get following error: 'NWInterface' cannot be constructed because it has no accessible initializers I also experimented with the .requiredInterfaceType property. Even when I set it to .wiredEthernet and then change it to .wifi, I am still unable to send requests over the Wi-Fi network. Here is the code I wrote: var multicast_params : NWParameters multicast_params = NWParameters.udp multicast_params.allowLocalEndpointReuse = true multicast_params.requiredInterfaceType = .wiredEthernet var ip = multicast_params.defaultProtocolStack.internetProtocol! as! NWProtocolIP.Options ip.disableMulticastLoopback = true connection_group = NWConnectionGroup(with: multicast_group_descriptor, using: multicast_params) connection_group.stateUpdateHandler = { state in print(state) if state == .ready { connection_group.send(content: "Hello from machine on 15".data(using: .utf8)) { error in print("Send to mg1 completed on wired Ethernet with error \(error?.errorCode)") var params = connection_group.parameters params.requiredInterfaceType = .wifi connection_group.send(content: "Hello from machine on 15 P2 on Wi-Fi".data(using: .utf8)) { error in print("Send to mg1 completed on Wi-Fi with error \(error?.errorCode)") } } } } Is this expected behavior when using NWConnectionGroup? Or is there a different approach I should take to ensure multicast requests are sent over both interfaces simultaneously? Any insights or suggestions would be greatly appreciated! Thanks in advance, Harshal

I’m developing an app designed for hospital environments, where public internet access may not be available. The app includes two components: the main app and a Local Connectivity Extension. Both rely on persistent TCP socket connections to communicate with a local server. We’re observing a recurring issue where the extension’s socket becomes unresponsive every 1–3 hours, but only when the device is on the lock screen, even if the main app remains in the foreground. When the screen is not locked, the connection is stable and no disconnections occur. ❗ Issue Details: • What’s going on: The extension sends a keep-alive ping packet every second, and the server replies with a pong and a system time packet. • The bug: The server stops receiving keep alive packets from the extension.  • On the server, we detect about 30 second gap on the server, a gap that shows no packets were received by the extension. This was confirmed via server logs and Wireshark).  • On the extension, from our logs there was no gap in sending packets. From it’s perspective, all packets were sent with no error.  • Because no packet are being received by the server, no packets will be sent to the extension. Eventually the server closes the connection due to keep-alive timeout.  • FYI we log when the NEAppPushProvider subclass sleeps and it did NOT go to sleep while we were debugging. 🧾 Example Logs: Extension log: 2025-03-24 18:34:48.808 sendKeepAliveRequest() 2025-03-24 18:34:49.717 sendKeepAliveRequest() 2025-03-24 18:34:50.692 sendKeepAliveRequest() ... // continuous sending of the ping packet to the server, no problems here 2025-03-24 18:35:55.063 sendKeepAliveRequest() 2025-03-24 18:35:55.063 keepAliveTimer IS TIME OUT... in CoreService. // this is triggered because we did not receive any packets from the server 2025-03-24 18:34:16.298 No keep-alive received for 16 seconds... connection ID=95b3... // this shows that there has been no packets being received by the extension ... 2025-03-24 18:34:30.298 Connection timed out on keep-alive. connection ID=95b3... // eventually closes due to no packets being received 2025-03-24 18:34:30.298 Remote Subsystem Disconnected {name=iPhone|Replica-Ext|...} ✅ Observations: • The extension process continues running and logging keep-alive attempts. • However, network traffic stops reaching the server, and no inbound packets are received by the extension. • It looks like the socket becomes silently suspended or frozen, without being properly closed or throwing an error. ❓Questions: • Do you know why this might happen within a Local Connectivity Extension, especially under foreground conditions and locked ? • Is there any known system behavior that might cause the socket to be suspended or blocked in this way after running for a few hours? Any insights or recommendations would be greatly appreciated. Thank you!

For important background information, read Extra-ordinary Networking before reading this. Share and Enjoy — Quinn “The Eskimo!” @ Developer Technical Support @ Apple let myEmail = "eskimo" + "1" + "@" + "apple.com" On Host Names I commonly see questions like How do I get the device’s host name? This question doesn’t make sense without more context. Apple systems have a variety of things that you might consider to be the host name: The user-assigned device name — This is a user-visible value, for example, Guy Smiley. People set this in Settings > General > About > Name. The local host name — This is a DNS name used by Bonjour, for example, guy-smiley.local. By default this is algorithmically derived from the user-assigned device name. On macOS, people can override this in Settings > General > Sharing > Local hostname. The reverse DNS name associated with the various IP addresses assigned to the device’s various network interfaces That last one is pretty much useless. You can’t get a single host name because there isn’t a single IP address. For more on that, see Don’t Try to Get the Device’s IP Address. The other two have well-defined answers, although those answers vary by platform. I’ll talk more about that below. Before getting to that, however, let’s look at the big picture. Big Picture The use cases for the user-assigned device name are pretty clear. I rarely see folks confused about that. Another use case for this stuff is that you’ve started a server and you want to tell the user how to connect to it. I discuss this in detail in Showing Connection Information in an iOS Server. However, most folks who run into problems like this do so because they’re suffering from one of the following misconceptions: The device has a DNS name. Its DNS name is unique. Its DNS name doesn’t change. Its DNS name is in some way useful for networking. Some of these may be true in some specific circumstances, but none of them are true in all circumstances. These issues are not unique to Apple platforms — if you look at the Posix spec for gethostname, it says nothing about DNS! — but folks tend to notice these problems more on Apple platforms because Apple devices are often deployed to highly dynamic network environments. So, before you start using the APIs discussed in this post, think carefully about your assumptions. And if you actually do want to work with DNS, there are two cases to consider: If you’re looking for the local host name, use the APIs discussed above. In other cases, it’s likely that the APIs in this post will not be helpful and you’d be better off focusing on DNS APIs [1]. [1] The API I recommend for this is DNS-SD. See the DNS section in TN3151 Choosing the right networking API. macOS To get the user-assigned device name, call the SCDynamicStoreCopyComputerName(_:_:) function. For example: let userAssignedDeviceName = SCDynamicStoreCopyComputerName(nil, nil) as String? To get the local host name, call the SCDynamicStoreCopyLocalHostName(_:) function. For example: let localHostName = SCDynamicStoreCopyLocalHostName(nil) as String? IMPORTANT This returns just the name label. To form a local host name, append .local.. Both routines return an optional result; code defensively! If you’re displaying these values to the user, use the System Configuration framework dynamic store notification mechanism to keep your UI up to date. iOS and Friends On iOS, iPadOS, tvOS, and visionOS, get the user-assigned device name from the name property on UIDevice. IMPORTANT Access to this is now restricted. For more on that, see the documentation for the com.apple.developer.device-information.user-assigned-device-name entitlement. There is no direct mechanism to get the local host name. Other APIs There are a wide variety of other APIs that purport to return the host name. These include: gethostname The name property on NSHost [1] The hostName property on NSProcessInfo (ProcessInfo in Swift) These are problematic for a number of reasons: They have a complex implementation that makes it hard to predict what value you’ll get back. They might end up trying to infer the host name from the network environment. The existing behaviour is hard to change due to compatibility concerns. Some of them are marked as to-be-deprecated. IMPORTANT The second issue is particularly problematic, because it involves synchronous DNS requests [2]. That’s slow in general. Worse yet, if the network environment is restricted in some way, these calls can be very slow, taking about 30 seconds to time out. Given these problems, it’s generally best to avoid calling these routines at all. [1] It also has a names property, which is a little closer to reality but still not particularly useful. [2] Actually, that’s not true for gethostname. Rather, that call just returns whatever was last set by sethostname. This is always fast. The System Configuration framework infrastructure calls sethostname to update the host name as the system state changes.

I'm able to discover a service with Bonjour, which gets me an nw_browse_result_t from which I can get an nw_endpoint_t and then an nw_connection_t. That's all fine. But this particular service runs on 3 ports. The port numbers of the other 2 ports are in the txt record (but they are well-known and stable anyway). How can I create 2 more nw_connection_t to the same host/IP but on a different port? I already have this working with NSNetService, but am trying to update to Network.framework. I've found nw_endpoint_get_address() but the docs say it returns null "if the endpoint is not of type nw_endpoint_type_address" and indeed nw_browse_result_t gives me an nw_endpoint_type_bonjour_service.

We have used ::gethostname to retrieve hostname in our tunnel provider extension and found it returns "localhost" on iOS 17+. So we changed to use [[NSProcessInfo processInfo] hostName]. However it often caused 30+ delay in the extension process on a few devices and always returns "localhost". The sysdiagnose shows a lot of DNS query logs as below: default mDNSResponder 2025-03-19 17:15:12.453769 +0800 75281: 0x11ad501 [R80937] DNSServiceCreateConnection START PID[79767](ACExtension) default mDNSResponder 2025-03-19 17:15:12.453892 +0800 75281: 0x11ad501 [R80938] DNSServiceQueryRecord START -- qname: <mask.hash: 'fNnSAdyuhKXqCny8+neXvw=='>, qtype: PTR, flags: 0x15000, interface index: -1, client pid: 79767 (ACExtension), name hash: 84de01e1 default mDNSResponder 2025-03-19 17:15:12.458395 +0800 75281: 0x11ad501 [R80939] DNSServiceQueryRecord START -- qname: <mask.hash: '2X6qN/YT0yh2psKwrGWokg=='>, qtype: PTR, flags: 0x15000, interface index: 0, client pid: 79767 (ACExtension), name hash: f25c923e default mDNSResponder 2025-03-19 17:15:12.462924 +0800 75281: 0x11ad501 [R80940] DNSServiceQueryRecord START -- qname: <mask.hash: 'peyRWEblLKbNvcOXPjSeMQ=='>, qtype: PTR, flags: 0x15000, interface index: 0, client pid: 79767 (ACExtension), name hash: 83323cc4

Hi, In my attempt to reconnect NEPacketTunnelProvider, when there is a network change, I am making use of self.reasserting and setTunnelNetworkSettings, and I am calling it with similar parameters as during the startTunnelWithOptions callback and making sure to make a new call for setting the includedRoutes: NEPacketTunnelNetworkSettings.IPv4Settings.includedRoutes = @[NEIPv4Route.defaultRoute]; This works sometimes, when I switch to a new network, but most of the time the traffic flow stops and it only works when I switch back to the first network. The only difference I could see in the routing table when it works is when there is a presence of Apple Specific network routes as follows: 17.57.145.133 link#22 UHWIig utun4 17.57.145.135 link#22 UHWIig utun4 17.57.145.137 link#22 UHWIig utun4 or 13.107.246.47 link#22 UHW3Ig utun4 17.57.145.148 link#22 UHWIig utun4 17.57.145.149 link#22 UHWIig utun4 37.252.171.52 link#22 UHWIig utun4 37.252.173.215 link#22 UHWIig utun4 Note: utun4 has index of 22 or some other combination of routes for Apple, I am not sure what these routes are for but they are present when NEPacketTunnelProvider starts. When switching to a new network and calling setTunnelNetworkSettings of NEPacketTunnelProvider, in any case when these routes are not present the traffic flow stops and it works otherwise. Switching back the first network, brings back these routes and the traffic flow continues, although it also goes through the same setTunnelNetworkSettings call and logic. I am not sure if these route table entries could be the culprit, because I did try to add them manually and that didn't help but my guess is that some system calls are failing for some unknown reason which might be the reason for the missing routes and some other configuration needed for proper traffic flow, which I am not seeing. Any help or information would be greatly appreciated. Thanks.

Dear Apple： We encountered a problem when using the Wi-Fi connection feature. When calling the Wi-Fi connection interface NEHotspotConfigurationManager applyConfiguration, it fails probabilistically. After analyzing the air interface packets, it appears that the Apple device did not send the auth message. How should we locate this issue? Are there any points to pay attention to when calling the Wi-Fi connection interface? Thanks

I had noticed that my slaac address changed between one beta and the other, but wasn't sure. Now with the RC 15.4 RC (24E247) I made point of preserving the info before updating from the previous beta. What I noticed is that not only the slaac address changes, but also the my ether address, even though I have it on Fixed in the settings. Is it expected that the ether, and the slaac, not be rotated after a OS update?

When I try to implement the new Background Task options in the same way as they show in the WWDC video (on watchOS) likes this: let config = URLSessionConfiguration.background(withIdentifier: "SESSION_ID") config.sessionSendsLaunchEvents = true let session = URLSession(configuration: config) let response = await withTaskCancellationHandler {       try? await session.data(for: request) } onCancel: {       let task = session.downloadTask(with: request))       task.resume() } I'm receiving the following error: Terminating app due to uncaught exception 'NSGenericException', reason: 'Completion handler blocks are not supported in background sessions. Use a delegate instead.' Did I forget something?

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.

I’m developing an app designed for hospital environments, where public internet access may not be available. The app includes two components: the main app and a Local Connectivity Extension. Both rely on persistent TCP socket connections to communicate with a local server. We’re observing a recurring issue where the extension’s socket becomes unresponsive every 1–3 hours, but only when the device is on the lock screen, even if the main app remains in the foreground. When the screen is not locked, the connection is stable and no disconnections occur. ❗ Issue Details: • What’s going on: The extension sends a keep-alive ping packet every second, and the server replies with a pong and a system time packet. • The bug: The server stops receiving keep alive packets from the extension.  • On the server, we detect about 30 second gap on the server, a gap that shows no packets were received by the extension. This was confirmed via server logs and Wireshark).  • On the extension, from our logs there was no gap in sending packets. From it’s perspective, all packets were sent with no error.  • Because no packet are being received by the server, no packets will be sent to the extension. Eventually the server closes the connection due to keep-alive timeout.  • FYI we log when the NEAppPushProvider subclass sleeps and it did NOT go to sleep while we were debugging. 🧾 Example Logs: Extension log: 2025-03-24 18:34:48.808 sendKeepAliveRequest() 2025-03-24 18:34:49.717 sendKeepAliveRequest() 2025-03-24 18:34:50.692 sendKeepAliveRequest() ... // continuous sending of the ping packet to the server, no problems here 2025-03-24 18:35:55.063 sendKeepAliveRequest() 2025-03-24 18:35:55.063 keepAliveTimer IS TIME OUT... in CoreService. // this is triggered because we did not receive any packets from the server Server log: 2025-03-24 18:34:16.298 No keep-alive received for 16 seconds... connection ID=95b3... // this shows that there has been no packets being received by the extension ... 2025-03-24 18:34:30.298 Connection timed out on keep-alive. connection ID=95b3... // eventually closes due to no packets being received 2025-03-24 18:34:30.298 Remote Subsystem Disconnected {name=iPhone|Replica-Ext|...} ✅ Observations: • The extension process continues running and logging keep-alive attempts. • However, network traffic stops reaching the server, and no inbound packets are received by the extension. • It looks like the socket becomes silently suspended or frozen, without being properly closed or throwing an error. ❓Questions: • Do you know why this might happen within a Local Connectivity Extension, especially under foreground conditions and locked ? • Is there any known system behavior that might cause the socket to be suspended or blocked in this way after running for a few hours? Any insights or recommendations would be greatly appreciated. Thank you!

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

Our app has a network extension (as I've mentioned lots 😄). We do an upgrade by downloading the new package, stopping & removing all of our components except for the network extension, and then installing the new package, which then loads a LaunchAgent causing the containing app to run. (The only difference between a new install and upgrade is the old extension is left running, but not having anything to tell it what to do, just logs and continues.) On some (but not all) upgrades... nothing ends up able to communicate via XPC with the Network Extension. My simplest cli program to talk to it gets Could not create proxy: Error Domain=NSCocoaErrorDomain Code=4099 "The connection to service named blah was invalidated: failed at lookup with error 3 - No such process." UserInfo={NSDebugDescription=The connection to service named bla was invalidated: failed at lookup with error 3 - No such process.} Could not communicate with blah Restarting the extension by doing a kill -9 doesn't fix it; neither does restarting the control daemon. The only solution we've come across so far is rebooting. I filed FB11086599 about this, but has anyone thoughts about this?

My app has local network permission on macOS Sequoia and works in most cases. I've noticed that after unlocking my MacBook Pro, the very first request will regularly fail with a No Route to Host. A simple retry resolves the issue, but I would have expected the very first request to succeed. Is this is a known issue on macOS Sequoia or by design? I'd prefer not to add a retry for this particular request as the app is a network utility.

I found a problem where a process tries to connect to System Extension and connection is invalidated. XPC listener has to be disposed and initialized again. This happens when System Extension executes tasks in following order: NSXPCListener initialized NSXPCListener.resume() NSProvider.startSystemExtensionMode() Result: Connection is invalidated and not only that the client has to retry connection, nut also System Extension must reinitialize listener (execute step 1 and 2). However if I call NSProvider.startSystemExtensionMode() NSXPCListener initialized NSXPCListener.resume() It works as expected and even if the connection is invalidated/interrupted, client process can always reconnect and no other action is necessary in System Extension (no need to reinitialize XPC listener), In Apple docs about NSProvider.startSystemExtensionMode() it says that this method starts handling request, but in another online article written by Scott Knight I found that startSystemExtensionMode() also starts listener server. Is that right? PLease could you add this info into the docs if it is so? https://knight.sc/reverse%20engineering/2019/08/24/system-extension-internals.html I would like to use following logic: Call NSProvider.startSystemExtensionMode() only under certain circumstances - I have received some configuration that I need to process and do some setup. If I don't receive it, there is no reason to call startSystemExtensionMode() yet, I don't need to handle handleNewFlow() yet. Connect XPC client to System Extension under certain conditions. Ideally communicate with client even though System Extension is not handling network requests yet, that is without receiving handleNewFlow(). Basically I consider XPC and System Extension handling network requests as separate things. Is that correct, are they separate and independent? Does XPC communication really depend on calling startSystemExtensionMode()? Another potential issue: Is it possible that XPC listener fails to validate connection when client tries to connect before System Extension manages to complete init and park the main thread in CFRunLoop? Note: These querstions arose mostly from handling upgrades of System Extension (extension is already running, network filter is created and is connected and new version of the app upgrades System Exension). Thanks.

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."

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.

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?