I am running a full-tunnel VPN using a Packet Tunnel Provider. During VPN setup, we configure DNS setting with specific DNS servers for all domains to be used by the tunnel. However, our project requires DNS resolution for every domain from both the VPN-provided DNS servers and the ISP’s DNS servers. When I attempt to use c-ares or other third-party libraries to resolve domains via the ISP DNS servers, these libraries only detect and use the VPN DNS servers instead. As a result, all queries fail. Is there a way on iOS to programmatically determine the ISP DNS servers while a full-tunnel VPN is active, or a system API that allows DNS queries to be explicitly resolved using the ISP’s DNS servers?

I am trying to intercept localhost connections within NETransparentProxyProvider system extension. As per NENetworkRule documentation If the address is a wildcard address (0.0.0.0 or ::) then the rule will match all destinations except for loopback (127.0.0.1 or ::1). To match loopback traffic set the address to the loopback address. I tried to add NWHostEndpoint *localhostv4 = [NWHostEndpoint endpointWithHostname:@"127.0.0.1" port:@""]; NENetworkRule *localhostv4Rule = [[NENetworkRule alloc] initWithDestinationNetwork:localhostv4 prefix:32 protocol:NENetworkRuleProtocolAny]; in the include network rules. I tried several variations of this rule like port 0, prefix 0 and some others. But the provider disregards the rule and the never receives any traffic going to localhost on any port. Is there any other configuration required to receive localhost traffic in NETransparentProxyProvider?

Hello, I'm working on a Transparent Proxy and when the proxy is being stopped, I'm stopping all the flows by calling flow.closeWriteWithError(POSIXError(.ECANCELED)) flow.closeReadWithError(POSIXError(.ECANCELED)) Then all the flows are deallocated. When deallocating the flow the crash occurs: OS Version: macOS 14.1.2 (23B92) Exception Type: EXC_BREAKPOINT (SIGTRAP) Exception Codes: 0x0000000000000001, 0x000000018c2ef704 Termination Reason: Namespace SIGNAL, Code 5 Trace/BPT trap: 5 Terminating Process: exc handler [553] Thread 32 Crashed:: Dispatch queue: <my dispatch queue> 0 CoreFoundation 0x18c2ef704 CF_IS_OBJC + 76 1 CoreFoundation 0x18c23f61c CFErrorGetDomain + 32 2 libnetworkextension.dylib 0x19fe56a00 flow_error_to_errno + 28 3 libnetworkextension.dylib 0x19fe56920 flow_handle_pending_write_requests + 216 4 libnetworkextension.dylib 0x19fe5667c __NEFlowDeallocate + 380 5 CoreFoundation 0x18c2efe28 _CFRelease + 292 6 NetworkExtension 0x19d208390 -[NEAppProxyFlow dealloc] + 36 Is there any way to debug what is happening and if it's related to closing the flow with POSIXError? 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" Broadcasts and Multicasts, Hints and Tips I regularly see folks struggle with broadcasts and multicasts on Apple platforms. This post is my attempt to clear up some of the confusion. This post covers both IPv4 and IPv6. There is, however, a key difference. In IPv4, broadcasts and multicasts are distinct concepts. In contrast, IPv6 doesn’t support broadcast as such; rather, it treats broadcasts as a special case of multicasts. IPv6 does have an all nodes multicast address, but it’s rarely used. Before reading this post, I suggest you familiarise yourself with IP addresses in general. A good place to start is The Fount of All Knowledge™. Service Discovery A lot of broadcast and multicast questions come from folks implementing their own service discovery protocol. I generally recommend against doing that, for the reasons outlined in the Service Discovery section of Don’t Try to Get the Device’s IP Address. There are, however, some good reasons to implement a custom service discovery protocol. For example, you might be working with an accessory that only supports this custom protocol [1]. If you must implement your own service discovery protocol, read this post and also read the advice in Don’t Try to Get the Device’s IP Address. IMPORTANT Sometimes I see folks implementing their own version of mDNS. This is almost always a mistake: If you’re using third-party tooling that includes its own mDNS implementation, it’s likely that this tooling allows you to disable that implementation and instead rely on the Bonjour support that’s built-in to all Apple platforms. If you’re doing some weird low-level thing with mDNS or DNS-SD, it’s likely that you can do that with the low-level DNS-SD API. [1] And whose firmware you can’t change! I talk more about this in Working with a Wi-Fi Accessory. API Choice Broadcasts and multicasts typically use UDP [1]. TN3151 Choosing the right networking API describes two recommended UDP APIs: Network framework BSD Sockets Our general advice is to prefer Network framework over BSD Sockets, but UDP broadcasts and multicasts are an exception to that rule. Network framework has very limited UDP broadcast support. And while it’s support for UDP multicasts is less limited, it’s still not sufficient for all UDP applications. In cases where Network framework is not sufficient, BSD Sockets is your only option. [1] It is possible to broadcast and multicast at the Ethernet level, but I almost never see questions about that. UDP Broadcasts in Network Framework Historically I’ve claimed that Network framework was useful for UDP broadcasts is very limited circumstances (for example, in the footnote on this post). I’ve since learnt that this isn’t the case. Or, more accurately, this support is so limited (r. 122924701) as to be useless in practice. For the moment, if you want to work with UDP broadcasts, your only option is BSD Sockets. UDP Multicasts in Network Framework Network framework supports UDP multicast using the NWConnectionGroup class with the NWMulticastGroup group descriptor. This support has limits. The most significant limit is that it doesn’t support broadcasts; it’s for multicasts only. Note This only relevant to IPv4. Remember that IPv6 doesn’t support broadcasts as a separate concept. There are other limitations, but I don’t have a good feel for them. I’ll update this post as I encounter issues. Local Network Privacy Some Apple platforms support local network privacy. This impacts broadcasts and multicasts in two ways: Broadcasts and multicasts require local network access, something that’s typically granted by the user. Broadcasts and multicasts are limited by a managed entitlement (except on macOS). TN3179 Understanding local network privacy has lots of additional info on this topic, including the list of platforms to which it applies. Send, Receive, and Interfaces When you broadcast or multicast, there’s a fundamental asymmetry between send and receive: You can reasonable receive datagrams on all broadcast-capable interfaces. But when you send a datagram, it has to target a specific interface. The sending behaviour is the source of many weird problems. Consider the IPv4 case. If you send a directed broadcast, you can reasonably assume it’ll be routed to the correct interface based on the network prefix. But folks commonly send an all-hosts broadcast (255.255.255.255), and it’s not obvious what happens in that case. Note If you’re unfamiliar with the terms directed broadcast and all-hosts broadcast, see IP address. The exact rules for this are complex, vary by platform, and can change over time. For that reason, it’s best to write your broadcast code to be interface specific. That is: Identify the interfaces on which you want to work. Create a socket per interface. Bind that socket to that interface. Note Use the IP_BOUND_IF (IPv4) or IPV6_BOUND_IF (IPv6) socket options rather than binding to the interface address, because the interface address can change over time. Extra-ordinary Networking has links to other posts which discuss these concepts and the specific APIs in more detail. Miscellaneous Gotchas A common cause of mysterious broadcast and multicast problems is folks who hard code BSD interface names, like en0. Doing that might work for the vast majority of users but then fail in some obscure scenarios. BSD interface names are not considered API and you must not hard code them. Extra-ordinary Networking has links to posts that describe how to enumerate the interface list and identify interfaces of a specific type. Don’t assume that there’ll be only one interface of a given type. This might seem obviously true, but it’s not. For example, our platforms support peer-to-peer Wi-Fi, so each device has multiple Wi-Fi interfaces. When sending a broadcast, don’t forget to enable the SO_BROADCAST socket option. If you’re building a sandboxed app on the Mac, working with UDP requires both the com.apple.security.network.client and com.apple.security.network.server entitlements. Some folks reach for broadcasts or multicasts because they’re sending the same content to multiple devices and they believe that it’ll be faster than unicasts. That’s not true in many cases, especially on Wi-Fi. For more on this, see the Broadcasts section of Wi-Fi Fundamentals. Snippets To send a UDP broadcast: func broadcast(message: Data, to interfaceName: String) throws { let fd = try FileDescriptor.socket(AF_INET, SOCK_DGRAM, 0) defer { try! fd.close() } try fd.setSocketOption(SOL_SOCKET, SO_BROADCAST, 1 as CInt) let interfaceIndex = if_nametoindex(interfaceName) guard interfaceIndex > 0 else { throw … } try fd.setSocketOption(IPPROTO_IP, IP_BOUND_IF, interfaceIndex) try fd.send(data: message, to: ("255.255.255.255", 2222)) } Note These snippet uses the helpers from Calling BSD Sockets from Swift. To receive UDP broadcasts: func receiveBroadcasts(from interfaceName: String) throws { let fd = try FileDescriptor.socket(AF_INET, SOCK_DGRAM, 0) defer { try! fd.close() } let interfaceIndex = if_nametoindex(interfaceName) guard interfaceIndex > 0 else { fatalError() } try fd.setSocketOption(IPPROTO_IP, IP_BOUND_IF, interfaceIndex) try fd.setSocketOption(SOL_SOCKET, SO_REUSEADDR, 1 as CInt) try fd.setSocketOption(SOL_SOCKET, SO_REUSEPORT, 1 as CInt) try fd.bind("0.0.0.0", 2222) while true { let (data, (sender, port)) = try fd.receiveFrom() … } } IMPORTANT This code runs synchronously, which is less than ideal. In a real app you’d run the receive asynchronously, for example, using a Dispatch read source. For an example of how to do that, see this post. If you need similar snippets for multicast, lemme know. I’ve got them lurking on my hard disk somewhere (-: Other Resources Apple’s official documentation for BSD Sockets is in the man pages. See Reading UNIX Manual Pages. Of particular interest are: setsockopt man page ip man page ip6 man page If you’re not familiar with BSD Sockets, I strongly recommend that you consult third-party documentation for it. BSD Sockets is one of those APIs that looks simple but, in reality, is ridiculously complicated. That’s especially true if you’re trying to write code that works on BSD-based platforms, like all of Apple’s platforms, and non-BSD-based platforms, like Linux. I specifically recommend UNIX Network Programming, by Stevens et al, but there are lots of good alternatives. https://unpbook.com Revision History 2025-09-01 Fixed a broken link. 2025-01-16 First posted.

I haven’t come across any official documentation regarding the limit on the number of Network Extensions macOS can run. However, I did see some discussions suggesting that Apple might restrict this to 5 extensions in macOS Tahoe. Is there any official confirmation on this?

Hi, We're hoping someone can help us determine why we're running into some odd behavior where a simple HTTP request is intermittently failing with error code NSURLErrorTimedOut (-1001) Background: HTTP request details: The request is sent from a PacketTunnelProvider and is meant to be a Captive Portal check. The request is insecure (HTTP, instead of HTTPS) but we have configured App Transport Security (ATS) to allow insecure HTTP loads from this hostname. See info.plist excerpt below. The request is sent using NSMutableURLRequest/NSURLSessionDataTask using an Ephemeral session configuration. We only modify 2 properties on NSMutableURLRequest The timeoutInterval property is set to 5 seconds. The allowsCellularAccess property is set to NO. No headers or other configuration are modified. NSURLSessionDataTask completionHandler receives an NSError: We checked the NSError's userInfo dictionary for an underlying error (NSUnderlyingErrorKey). The underlying error shows the same code NSURLErrorTimedOut (-1001). We haven't seen any underlying errors with code NSURLErrorAppTransportSecurityRequiresSecureConnection (-1022) . On a laptop, we confirmed that the Captive portal check site is accessible and loads correctly. Laptop and iOS device are on the same Wi-fi. I've witnessed the error in the debugger, and been able to load the site on my laptop at the same time. So, we don't have any reason to believe this is server related. The PacketTunnelProvider is configured to only handle DNS queries and is not intercepting/routing the HTTP traffic. The DNS query for the Captive portal request is handled correctly. In fact, outside of the PacketTunnelProvider, all sites load in Mobile Safari. So, we're not breaking internet on this device. In other words, we have no reason to believe our DNS handling is interfering with the HTTP request since other HTTP requests are working as expected. We setup CFNetwork Diagnostic Logging (https://developer.apple.com/documentation/network/debugging-https-problems-with-cfnetwork-diagnostic-logging) In console.app, we are able to find some logging on the Timeout See excerpt from Console.app's log below. We confirmed that the nscurl tool did not flag the request (https://developer.apple.com/documentation/security/identifying-the-source-of-blocked-connections) All ATS tests run with nscurl were successful. See nscurl command used below. Questions: What are next steps to debug this intermittent timeout? What should we look for in the CFNetwork Diagnostic Logging to help debug the issue further? Thanks in advance for your help! ATS configuration setup in both the UI and the PacketTunnel's info.plist file: <key>NSAppTransportSecurity</key> <dict> <key>NSExceptionDomains</key> <dict> <key>subdomain.subdomain.example.com</key> <dict> <key>NSExceptionAllowsInsecureHTTPLoads</key> <true/> <key>NSIncludesSubdomains</key> <true/> </dict> </dict> </dict> Excerpt from Console.app's log: CFNetwork Example PacketTunnel 10836 Diagnostics default 11:30:33.029032-0700 CFNetwork Diagnostics [3:834] 11:30:32.946 { Did Timeout: (null) Loader: request GET http://subdomain.subdomain.example.com/content/cpcheck.txt HTTP/1.1 Timeout Interval: 5.000 seconds init to origin load: 0.000592947s total time: 5.00607s total bytes: 0 } [3:834] nscurl command $ /usr/bin/nscurl --ats-diagnostics --verbose http://subdomain.subdomain.example.com/content/cpcheck.txt

Hi, I developed a network extension program on macOS. I tried to update the program by changing the version number. My update process was to first turn off network filtering via "NEFilterManager.sharedManager.enabled = NO", and then use "[OSSystemExtensionRequest activationRequestForExtension:bundleid queue:dispatch_get_global_queue(DISPATCH_QUEUE_PRIORITY_HIGH, 0)];" to let the system replace the old network extension program. However, sometimes the old network extension process will become a zombie process like pid=86621 in the figure. As long as the zombie process exists, the network cannot be used. After about 10 minutes, it will be cleared and the network will be available. Restarting Wi-Fi can also clear the zombie process immediately. Why is this? How to avoid this problem?

I need to know the https address of a certain page within my app. This is going to be used as a redirect URL. I don't think it is a good idea to use deep links because it has to be an https address. I don't think Universal Links will work because it is not my website that I will be communicating with.

We are developing a client server application using TCP bsd sockets. When our client is connected to the server, copying another client .app bundle from a file server on the same machine (using Finder or terminal using cp), occasionally causes the first client to disconnect. The client receives an EBROKENPIPE error when attempting to write to its socket. In the Console, the following message appears just before the disconnection: necp_socket_find_policy_match: Marking socket in state 258 as defunct This issue seems to occur only when copying an .app bundle signed with the same TeamIdentifier as the running client. Copying arbitrary files or bundles with a different TeamIdentifier does not trigger the problem. We are running on macOS 15.5. The issue appears specific to macOS 15 and was not observed on earlier versions. Any help or pointers would be greatly appreciated!

I'm developing a Matter-over-thread generic switch with 2 generic switch endpoints. This is configured as an Intermittently Connected Device with Long Idle Time. I have an Apple TV serving as the thread border router. I'm able to commission the device successfully in the Home app and assign actions to each of the buttons however when the device is rebooted the subscription doesn't appear to resume successfully and the buttons no longer work. I've tested this on various SOC's with their respective SDKs including ESP32-C6, nrf52840 and EFR32MG24 and the behaviour was consistent across all of them. It was working originally when I first started out on the ESP32-C6, then the issue popped up first when I was testing the nrf52840. In that SDK I set persistent subscriptions explicitly and it seemed to resolve the issue until it popped up again when I found that unplugging and restarting the Apple TV completely which appeared to fix the issue with subscriptions not resuming. Recently I've added a Home Pod Mini Gen 2 to the matter fabric so there are now two TBR on the network and restarting both the Apple TV and the HomePod doesn't appear to resolve the issue anymore and the subscriptions are not resuming across all three SOC's on device reboot I'm wondering if there might be something preventing the subscriptions from resuming?

I'm a long-time developer, but pretty new to Swift. I'm trying to get information from a web service (and found code online that I adjusted to build the function below). (Note: AAA_Result -- referenced towards the end -- is another class in my project) Trouble is, I'm getting the subject error on the call to session.dataTask. Any help/suggestions/doc pointers will be greatly appreciated!!! var result: Bool = false var cancellable: AnyCancellable? self.name = name let params = "json={\"\"}}" // removed json details let base_url = URL(string: "https://aaa.yyy.com?params=\(params)&format=json")! // removed URL specifics do { let task = URLSession.shared.dataTask(with: base_url) { data, response, error in if let error = error { print("Error: \(error)") } guard let response = response as? HTTPURLResponse, (200...299).contains(response.statusCode) else { print("Error \(String(describing: response))") } do { let decoder = JSONDecoder() let ar = try decoder.decode(AAA_Result.self, from: response.value) // removed specific details... result = true } catch { print(error) } } task.resume() } catch { print(error) } return result }

The content filtering functionality works perfectly when I install the app directly on my mobile device from Xcode. However, when the app is distributed via TestFlight, the app does not prompt users to save configurations, which causes the configuration-saving process to fail. This app is meant for public use. As per my understanding from TN3134, content filter apps can be shipped for devices running iOS 16 and later. iOS app extension 9.0. supervised devices only iOS app extension 15.0. apps using Screen Time API iOS app extension 16.0. per app on managed devices

Hello, Our app uses Network Extension / Packet Tunnel Provider to establish VPN connections on macOS and iOS. We have observed that after creating a utun device and adding any IPv4 routes (NEPacketTunnelNetworkSettings.IPv4Settings), the OS automatically adds several host routes via utun to services such as Akamai, Apple Push, etc. These routes appear to correspond to TCP flows that were active at the moment the VPN connection was established. When a particular TCP flow ends, the corresponding host route is deleted. We understand this is likely intended to avoid breaking existing TCP connections. However, we find the behavior of migrating existing TCP flows to the new utun interface simply because any IPv4 route is added somewhat questionable. This approach would make sense in a "full-tunnel" scenario — for example, when all IPv4 traffic (e.g., 0.0.0.0/0) is routed through the tunnel — but not necessarily in a "split-tunnel" configuration where only specific IPv4 routes are added. Is there any way to control or influence this behavior? Would it be possible for FlowDivert to differentiate between full-tunnel and split-tunnel cases, and only preserve existing TCP flows via utun in the full-tunnel scenario? Thank you.

I'm using NWBrowser to search for a server that I hosted. The browser does find my service but when it tries to connect to it, it gets stuck in the preparing phase in NWConnection.stateUpdateHandler. When I hardcode the local IP address of my computer (where the server is hosted) into NWConnection it works perfectly fine and is able to connect. When it gets stuck in the preparing phase, it gives me the warnings and error messages in the image below. You can also see that the service name is correct and it is found. I have tried _http._tcp and _ssh._tcp types and neither work. This is what my code looks like: func findServerAndConnect(port: UInt16) { print("Searching for server...") let browser = NWBrowser(for: .bonjour(type: "_ssh._tcp", domain: "local."), using: .tcp) browser.browseResultsChangedHandler = { results, _ in print("Found results: \(results)") for result in results { if case let NWEndpoint.service(name, type_, domain, interface) = result.endpoint { if name == "PocketPadServer" { print("Found service: \(name) of type \(type_) in domain \(domain) on interface \(interface)") // Construct the full service name, including type and domain let fullServiceName = "\(name).\(type_).\(domain)" print("Full service name: \(fullServiceName), \(result.endpoint)") self.connect(to: result.endpoint, port: port) browser.cancel() break } } } } browser.start(queue: .main) } func connect(to endpoint: NWEndpoint, port: UInt16) { print("Connecting to \(endpoint) on port \(port)...") // endpoint = NWEndpoint( let tcpParams = NWProtocolTCP.Options() tcpParams.enableFastOpen = true tcpParams.keepaliveIdle = 2 let params = NWParameters(tls: nil, tcp: tcpParams) params.includePeerToPeer = true // connection = NWConnection(host: NWEndpoint.Host("xx.xxx.xxx.xxx"), port: NWEndpoint.Port(3000), using: params) connection = NWConnection(to: endpoint, using: params) connection?.pathUpdateHandler = { path in print("Connection path update: \(path)") if path.status == .satisfied { print("Connection path is satisfied") } else { print("Connection path is not satisfied: \(path.status)") } } connection?.stateUpdateHandler = { newState in DispatchQueue.main.async { switch newState { case .ready: print("Connected to server") self.pairing = true self.receiveMessage() case .failed(let error): print("Connection failed: \(error)") self.isConnected = false case .waiting(let error): print("Waiting for connection... \(error)") self.isConnected = false case .cancelled: print("Connection cancelled") self.isConnected = false case .preparing: print("Preparing connection...") self.isConnected = false default: print("Connection state changed: \(newState)") break } } } connection?.start(queue: .main) }

We put the apple-app-site-association file at https://ourdomain.com.tr/.well-known/apple-app-site-association. When we send a request to url, we get 200 response code every time and we can see the file. But sometimes when we try to access https://app-site-association.cdn-apple.com/a/v1/ourdomain.com.tr url with browser or CMD tool, we are facing with 404 response code. There isn't any ip adress filter in our systems and we tried using vpn for sending same request from different locations(america and europe) but nothing changed. In addition, can anyone provide the ip list of apple cdn servers to check the F5 Load balancer WAF logs? CMD output: C:\Users\Name>curl -Lv https://app-site-association.cdn-apple.com/a/v1/ourdomain.com.tr Host app-site-association.cdn-apple.com:443 was resolved. IPv6: (none) IPv4: 17.253.122.197, 17.253.15.210, 17.253.122.196, 17.253.107.201, 17.253.57.203, 17.253.15.198, 17.253.57.200 Trying 17.253.122.197:443... Connected to app-site-association.cdn-apple.com (17.253.122.197) port 443 schannel: disabled automatic use of client certificate ALPN: curl offers http/1.1 ALPN: server accepted http/1.1 using HTTP/1.x GET /a/v1/ourdomain.com HTTP/1.1 Host: app-site-association.cdn-apple.com User-Agent: curl/8.9.1 Accept: / Request completely sent off schannel: remote party requests renegotiation schannel: renegotiating SSL/TLS connection schannel: SSL/TLS connection renegotiated < HTTP/1.1 404 Not Found < Apple-Failure-Details: {"cause":"context deadline exceeded (Client.Timeout exceeded while awaiting headers)"} < Apple-Failure-Reason: SWCERR00301 Timeout < Apple-From: https://ourdomain.com.tr/.well-known/apple-app-site-association < Apple-Try-Direct: true < Cache-Control: max-age=3600,public < Content-Length: 10 < Content-Type: text/plain; charset=utf-8 < Date: Mon, 14 Apr 2025 12:52:04 GMT < Expires: Mon, 14 Apr 2025 12:52:14 GMT < Age: 1770 < Via: http/1.1 uklon5-vp-vst-004.ts.apple.com (acdn/268.14469), https/1.1 uklon5-vp-vfe-002.ts.apple.com (acdn/268.14469), http/1.1 frmrs1-edge-mx-008.ts.apple.com (acdn/268.14469), http/1.1 frmrs1-edge-fx-005.ts.apple.com (acdn/268.14469) < X-Cache: hit-fresh, hit-stale, hit-fresh, hit-fresh < CDNUUID: 9e72cf99-1503-4644-9ea3-173328a25c94-31496306226 < Connection: keep-alive < Not Found Connection #0 to host app-site-association.cdn-apple.com left intact

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?

Hello, I'm running into an issue while developing an iOS app that requires local network access. I’m using the latest MacBook Air M4 with macOS sequoia 15.5 and Xcode 16.1. In the iOS Simulator, my app fails to discover devices connected to the same local network. I’ve already added the necessary key to the Info.plist: NSLocalNetworkUsageDescription This app needs access to local network devices. When I run the app on a real device and M2 Chip Macbook's simulators, it works fine for local network permission as expected. However, in the M4 Chip Macbook's Simulator: The app can’t find any devices on the local network Bonjour/mDNS seems not to be working as well I’ve tried the following without success: Restarting Simulator and Mac Resetting network settings in Simulator Confirming app permissions under System Settings > Privacy & Security Has anyone else encountered this issue with the new Xcode/macOS combo? Is local network access just broken in the Simulator for now, or is there a workaround? Thanks in advance!

When I use NSURLSessionTaskTransactionMetrics property domainLookupStartDate and domainLookupEndDate to calculate the duration of DNS, sometimes I get 4294893875545978 or -4294893875545978 return method like this [NSNumber numberWithLongLong:[taskMetrics.domainLookupEndDate timeIntervalSinceDate:taskMetrics.domainLookupStartDate?]*1000000000] The hexadecimal value of 4294893875545978 is 0xF3F3F3F3F3F3A. Is 4294893875545978 a special value？

We’re looking to implement a custom IPSec IKEv2 VPN using the Packet Tunnel Provider network extension on iOS because we need to add extra information to EAP, which the built-in IKEv2 VPN configuration does not support. Is it possible to handle the full IKEv2 negotiation and IPSec tunneling within the Packet Tunnel Provider extension? Or are there limitations that would prevent implementing a full IKEv2 stack this way? Any insights or alternative approaches would be appreciated. Thanks!

I am currently developing a custom-protocol VPN application for iOS using PacketTunnelProvider. I have also integrated an HTTP proxy service, which is launched via a dylib. The overall flow is as follows: App -> VPN TUN -> Local HTTP Proxy -> External Network I have a question: I am capturing all traffic, and normally, requests sent out by the HTTP proxy are also captured again by the VPN. However, when I send requests using createUdpSession in my code, they are not being captured by the virtual interface (TUN). What could be the reason for this? override func startTunnel(options: [String : NSObject]?, completionHandler: @escaping (Error?) -> Void) { let tunnelNetworkSettings = NEPacketTunnelNetworkSettings(tunnelRemoteAddress: "192.168.18.0") tunnelNetworkSettings.mtu=1400 let ipv4Settings = NEIPv4Settings(addresses: ["192.169.10.10"], subnetMasks: ["255.255.255.0"]) ipv4Settings.includedRoutes=[NEIPv4Route.default()] ipv4Settings.excludedRoutes = [NEIPv4Route(destinationAddress: "10.0.0.0", subnetMask: "255.0.0.0"), NEIPv4Route(destinationAddress: "172.16.0.0", subnetMask: "255.240.0.0"), NEIPv4Route(destinationAddress: "192.168.0.0", subnetMask: "255.255.0.0"), NEIPv4Route(destinationAddress:"127.0.0.0", subnetMask: "255.0.0.0"), ] tunnelNetworkSettings.ipv4Settings = ipv4Settings // Configure proxy settings let proxySettings = NEProxySettings() proxySettings.httpEnabled = true proxySettings.httpServer = NEProxyServer(address: "127.0.0.1", port: 7890) proxySettings.httpsEnabled = true proxySettings.httpsServer = NEProxyServer(address: "127.0.0.1", port: 7890) proxySettings.excludeSimpleHostnames = true proxySettings.exceptionList=["localhost","127.0.0.1"] tunnelNetworkSettings.proxySettings = proxySettings setTunnelNetworkSettings(tunnelNetworkSettings) { [weak self] error in if error != nil { completionHandler(error) return } completionHandler(nil) let stack = TUNInterface(packetFlow: self!.packetFlow) RawScoketFactory.TunnelProvider=self stack.register(stack: UDPDirectStack()) stack.register(stack: TCPDirectStack()) stack.start() } } NWUdpSession.swift // // NWUDPSocket.swift // supervpn // // Created by TobbyQuinn on 2025/2/3. // import Foundation import NetworkExtension import CocoaLumberjack public protocol NWUDPSocketDelegate: AnyObject{ func didReceive(data:Data,from:NWUDPSocket) func didCancel(socket:NWUDPSocket) } public class NWUDPSocket:NSObject{ private let session:NWUDPSession private let timeout:Int private var pendingWriteData: [Data] = [] private var writing = false private let queue:DispatchQueue=QueueFactory.getQueue() public weak var delegate:NWUDPSocketDelegate? public init?(host:String,port:UInt16,timeout:Int=Opt.UDPSocketActiveTimeout){ guard let udpSession = RawScoketFactory.TunnelProvider?.createUDPSession(to: NWHostEndpoint(hostname: host, port: "\(port)"), from: nil) else{ return nil } session = udpSession self.timeout=timeout super.init() session.addObserver(self, forKeyPath: #keyPath(NWUDPSession.state),options: [.new], context: nil) session.setReadHandler({ dataArray, error in self.queueCall{ guard error == nil, let dataArray = dataArray else { print("Error when reading from remote server or connection reset") return } for data in dataArray{ self.delegate?.didReceive(data: data, from: self) } } }, maxDatagrams: 32) } /** Send data to remote. - parameter data: The data to send. */ public func write(data: Data) { pendingWriteData.append(data) checkWrite() } public func disconnect() { session.cancel() } public override func observeValue(forKeyPath keyPath: String?, of object: Any?, change: [NSKeyValueChangeKey : Any]?, context: UnsafeMutableRawPointer?) { guard keyPath == "state" else { return } switch session.state { case .cancelled: queueCall { self.delegate?.didCancel(socket: self) } case .ready: checkWrite() default: break } } private func checkWrite() { guard session.state == .ready else { return } guard !writing else { return } guard pendingWriteData.count > 0 else { return } writing = true session.writeMultipleDatagrams(self.pendingWriteData) {_ in self.queueCall { self.writing = false self.checkWrite() } } self.pendingWriteData.removeAll(keepingCapacity: true) } private func queueCall(block:@escaping ()->Void){ queue.async { block() } } deinit{ session.removeObserver(self, forKeyPath: #keyPath(NWUDPSession.state)) } }