General: DevForums tag: Network Extension Network Extension framework documentation Network Extension and VPN Glossary DevForums post Debugging a Network Extension Provider DevForums post Exporting a Developer ID Network Extension DevForums post Network Extension vs ad hoc techniques on macOS DevForums post Extra-ordinary Networking DevForums post Wi-Fi management: Wi-Fi Fundamentals DevForums post TN3111 iOS Wi-Fi API overview technote How to modernize your captive network developer news post iOS Network Signal Strength DevForums post See also Networking Resources. Share and Enjoy — Quinn “The Eskimo!” @ Developer Technical Support @ Apple let myEmail = "eskimo" + "1" + "@" + "apple.com"

I was trying to log the flow description using control filter and data filter. But when I am trying to log the proc ID in control filter, it is always 0, but in data filter, it logs some value. Same goes with the eproc ID. I want to use the flow description data in some other target so I will be sending the data using sockets and I cannot share data from data filter due to its restrictions and control filter isn't providing the proc ID. What should I do?

We are implementing a Transparent Proxy for HTTPS (via TCP and QUIC). The following rules are set in startProxy: settings.includedNetworkRules = [ NENetworkRule(destinationNetwork: NWHostEndpoint(hostname: "0.0.0.0", port: "443"), prefix: 0, protocol: .TCP), NENetworkRule(destinationNetwork: NWHostEndpoint(hostname: "::", port: "443"), prefix: 0, protocol: .TCP), NENetworkRule(destinationNetwork: NWHostEndpoint(hostname: "0.0.0.0", port: "443"), prefix: 0, protocol: .UDP), NENetworkRule(destinationNetwork: NWHostEndpoint(hostname: "::", port: "443"), prefix: 0, protocol: .UDP) ] Handling TCP connections seems to work fine. But opening UDP flows from Chrome (or Brave) always fails with Error Domain=NEAppProxyFlowErrorDomain Code=2 "The peer closed the flow" (Doing the same for Firefox works!) BTW: We first create a remote UDP connection (using the Network framework) and when it is in the ready state, we use connection?.currentPath?.localEndpoint as the localEndpoint parameter in the open method of the flow. Is it a known issue that QUIC connections from Chrome cannot be handled by a Transparent Proxy Provider?

I just want Mac Catalyst app can look up the SSID of the currently connected WiFI. Xcode returns I can't use CoreWLan in Mac Catalyst, so I used NEHotspotNetwork, although I do not have convince whether Mac Catalyst allows it. The same code of destination works fine on iPhone, but not on Mac Catalyst and Mac(Designed for iPad). What is the proper way to get SSID of WiFI in Mac Catalyst? Is there another way to do this? The code I tried is below and I used CoreLocation API before call this function. func getWiFiSsid() { NEHotspotNetwork.fetchCurrent { network in if let network = network { print(network) } else { print("network is nil!") } } } Below is Entitlement file. Entitlements for app sandbox is removed when I run in Mac(Designed for iPad). <?xml version="1.0" encoding="UTF-8"?> <!DOCTYPE plist PUBLIC "-//Apple//DTD PLIST 1.0//EN" "http://www.apple.com/DTDs/PropertyList-1.0.dtd"> <plist version="1.0"> <dict> <key>com.apple.developer.networking.HotspotConfiguration</key> <true/> <key>com.apple.developer.networking.networkextension</key> <array/> <key>com.apple.developer.networking.wifi-info</key> <true/> <key>com.apple.security.app-sandbox</key> <true/> <key>com.apple.security.network.client</key> <true/> <key>com.apple.security.network.server</key> <true/> <key>com.apple.security.personal-information.location</key> <true/> </dict> </plist> Below is Info.plist file. <?xml version="1.0" encoding="UTF-8"?> <!DOCTYPE plist PUBLIC "-//Apple//DTD PLIST 1.0//EN" "http://www.apple.com/DTDs/PropertyList-1.0.dtd"> <plist version="1.0"> <dict> <key>CFBundleDevelopmentRegion</key> <string>$(DEVELOPMENT_LANGUAGE)</string> <key>CFBundleExecutable</key> <string>$(EXECUTABLE_NAME)</string> <key>CFBundleIdentifier</key> <string>$(PRODUCT_BUNDLE_IDENTIFIER)</string> <key>CFBundleInfoDictionaryVersion</key> <string>6.0</string> <key>CFBundleName</key> <string>$(PRODUCT_NAME)</string> <key>CFBundlePackageType</key> <string>APPL</string> <key>CFBundleShortVersionString</key> <string>1.0</string> <key>CFBundleVersion</key> <string>1</string> <key>LSRequiresIPhoneOS</key> <true/> <key>UILaunchStoryboardName</key> <string>LaunchScreen</string> <key>UIMainStoryboardFile</key> <string>Main</string> <key>UIRequiredDeviceCapabilities</key> <array> <string>armv7</string> </array> <key>UISupportedInterfaceOrientations</key> <array> <string>UIInterfaceOrientationPortrait</string> <string>UIInterfaceOrientationLandscapeLeft</string> <string>UIInterfaceOrientationLandscapeRight</string> </array> <key>UISupportedInterfaceOrientations~ipad</key> <array> <string>UIInterfaceOrientationPortrait</string> <string>UIInterfaceOrientationPortraitUpsideDown</string> <string>UIInterfaceOrientationLandscapeLeft</string> <string>UIInterfaceOrientationLandscapeRight</string> </array> <key>NSLocationUsageDescription</key> <string>Determine whether the ssid of current Wi-Fi connection</string> <key>NSLocationWhenInUseUsageDescription</key> <string>Determine whether the ssid of current Wi-Fi connection</string> </dict> </plist> The console log is below. NEHotspotNetwork nehelper sent invalid result code [1] for Wi-Fi information request

We are developing a tunnel based on transparent proxy system extension. We want to be able to decide whether to handle certain TCP flows based on FQDN. So, is there a way to peek into TCPFlow data like we can in ContentFilter which will allow use to parse and check for SNI or Host-header? As far as I understand, we can read data from flows until we have returned a decision from handleNewFlow.

Hi, For one our requirement sendProviderMessage is been used to send some event/message from app to system extension, In my requirement, responseHandler in system extension would get explicitly called approximately after 1 min due to some async download file task. But observing some strange behavior that responseHandler is getting called implicitly after ~20-30 seconds even before the code hit the place where its called explicitly. And that is the only place I'm calling responseHandler. Can somebody please help about this strange behavior, Is there any implicit timeout interval associated with the responseHandler. Thanks &amp;amp; Regards, Preethi

Hi, I'm working on a VPN app using NEPacketTunnelProvider. The primary goal is to capture outgoing network packets while keeping the internet connection functional. However, with the current implementation, the internet connection stops working after the VPN is enabled. Specifically, browsers like Safari and Chrome fail to load any website (e.g., google.com or apple.com). Below is the relevant code snippet from my startTunnel method: override func startTunnel(options: [String : NSObject]?, completionHandler: @escaping (Error?) -> Void) { os_log("Starting tunnel...", log: self.log, type: .info) // Configure network settings let networkSettings = NEPacketTunnelNetworkSettings(tunnelRemoteAddress: "10.0.0.1") networkSettings.ipv4Settings = NEIPv4Settings(addresses: ["10.0.0.2"], subnetMasks: ["255.255.255.0"]) networkSettings.ipv4Settings?.includedRoutes = [NEIPv4Route.default()] // Route all traffic through tunnel networkSettings.ipv4Settings?.excludedRoutes = [] // No exceptions // DNS configuration networkSettings.dnsSettings = NEDNSSettings(servers: ["8.8.8.8"]) //networkSettings.dnsSettings?.matchDomains = [""] // Uncommented to process all domains // MTU configuration networkSettings.mtu = 1400 // Apply tunnel network settings setTunnelNetworkSettings(networkSettings) { [weak self] error in guard let self = self else { return } if let error = error { os_log("Failed to set tunnel settings: %{public}@", log: self.log, type: .error, error.localizedDescription) completionHandler(error) return } os_log("Tunnel settings applied successfully", log: self.log, type: .info) self.readPackets() // Start reading packets completionHandler(nil) } } private func readPackets() { let queue = DispatchQueue(label: "PacketProcessing", qos: .userInitiated) self.packetFlow.readPackets { packets, protocols in queue.async { for (i, packet) in packets.enumerated() { self.logPacketInfo(packet: packet, protocolCheck: Int32(protocols[i])) self.packetFlow.writePackets([packet], withProtocols: [protocols[i]]) // Re-send packet } self.readPackets() // Continue reading } } } Questions Are there additional configurations required to ensure that the VPN forwards packets correctly to maintain internet connectivity? Could there be a missing setting related to includedRoutes or dnsSettings that is causing the issue? How should packets be properly handled in the readPackets method to avoid breaking the internet connection? With this approach, is it possible to read network packets generated by browsers like Safari and Chrome? Please understand that it's my first time leaving a question, so it's not readable. Thank you!!

Hi, We have been granted the com.apple.managed.vpn.shared entitlement and are able to use it for builds/TestFlight builds. We can access the cert in a mobile config. and everything works fine. However when we try to archive a build and distribute for App Store Connect it fails if the entitlement file contains this entry. If we take it out the upload succeeds but the app can't load the cert from the keychain. The Distribution profile has the entry: keychain-access-groups: [TEAM ID].*, com.apple.managed.vpn.shared Is there an extra step for App Store Connect builds? Thanks, Dave

Hi, One of our customers is seeing a crash in our Content Filter in our network system extension. We're kind of at a loss for the cause of this as only one specific person is running into this and we're not at all in the stacktrace, out of the hundreds of others deployed with our extension. It would be greatly appreciated if we could have any help in diagnosing this issue. Attached is the crash report, and below is the crashing stacktrace. If this crash log is not sufficient, I have many more from the customer that I can attatch here. crash.txt Thread 4 Crashed:: Dispatch queue: NEFilterExtensionProviderContext queue 0 libsystem_kernel.dylib 0x18cd4e600 __pthread_kill + 8 1 libsystem_pthread.dylib 0x18cd86f70 pthread_kill + 288 2 libsystem_c.dylib 0x18cc93908 abort + 128 3 libc++abi.dylib 0x18cd3d44c abort_message + 132 4 libc++abi.dylib 0x18cd2ba40 demangling_terminate_handler() + 348 5 libobjc.A.dylib 0x18c9d13e4 _objc_terminate() + 156 6 libc++abi.dylib 0x18cd3c710 std::__terminate(void (*)()) + 16 7 libc++abi.dylib 0x18cd3c6b4 std::terminate() + 108 8 libdispatch.dylib 0x18cbd466c _dispatch_client_callout + 40 9 libdispatch.dylib 0x18cbdbc60 _dispatch_lane_serial_drain + 744 10 libdispatch.dylib 0x18cbdc79c _dispatch_lane_invoke + 432 11 libdispatch.dylib 0x18cbe77e8 _dispatch_root_queue_drain_deferred_wlh + 288 12 libdispatch.dylib 0x18cbe7034 _dispatch_workloop_worker_thread + 540 13 libsystem_pthread.dylib 0x18cd833d8 _pthread_wqthread + 288 14 libsystem_pthread.dylib 0x18cd820f0 start_wqthread + 8

I've implemented a custom VPN for macOS (system extension, Packet Tunnel Provider, Developer ID). My tunneling logic uses BSD sockets. My VPN is configured with on-demand and should always connect when there's traffic: targetManager?.isOnDemandEnabled = true targetManager?.onDemandRules = [NEOnDemandRuleConnect()] I have encountered some issues when the device enters sleep (or waking up from sleep). I've tried two scenarios. Scenario 1: protocolConfiguration?.disconnectOnSleep = true With this flag set, the OS will disconnect the VPN just before entering to sleep. However, there were cases when the OS disconnected the VPN but immediately restarted it - probably because of how I defined the on-demand rules. This resulted in the VPN disconnection, then trying to reconnect, and then the Mac entered sleep. When the Mac woke up, the VPN didn't work well. Is there a way to avoid waking up, just before the Mac enters sleep? Scenario 2: protocolConfiguration?.disconnectOnSleep = false Disconnect on sleep is unset, and I've implemented the sleep/wake functions at the provider. With this configuration, the OS won't disconnect the VPN, so even in sleep, the extension should stay 'alive,' so it won't have the problem from (1). But in this case, I had other problems: On sleep, I'm disconnecting the tunnel. But sometimes, on wake(), all my network calls fail. Are the interfaces still down? How can I detect this case from the system extension? Is it possible that the OS would call sleep and then quickly call wake? Is it possible that after sleep, the OS would call the startTunnelWithOptions() function? Is it possible to restart the extension from a clean state right from the wake() function?

In our setup, our Transparent Proxy (call it TP1) funnels traffic to a helper process running on the same machine (call it Helper), which then actually sends out the traffic to the wider Internet. Now say there's another Transparent Proxy, TP2, on the same machine. Assuming TP1 gets hold of the traffic first, the sequence would look like so: Safari --> TP1 --> Helper --> TP2 We want to make it appear to TP2 that the incoming traffic is from Safari, rather than from the Helper process. We are aware of the Network framework's setMetadata API, but this does not look appropriate for us to use here. The Helper process is pre-existing Golang code, which at best can interface with "pure" (ie BSD) sockets-based C code. In order to use the setMetadata API, looks like we will need to rewrite the entire networking logic to use nw_connection_t (or similar) API, which is too much work, so is infeasible for us to use. Is there a way to make the setMetadata API work at a socket level? e.g., associate the metadata with a socket so that whatever data is sent out on the socket by the Helper will seem to TP2 to be coming from the desired source process. Assuming there isn't such a way, please consider this an Enhancement Request to make it so! Also, this reveals another complication: If and when this Enhancement is implemented, our own TP1 (which interepted the traffic in the first place) would end up thinking that the traffic is from Safari, so ends up re-intercepting it, causing a loop. Safari --> TP1 --> Helper (invokes setMetadata) --> TP1 --> Helper ... Which leads to the next Enhancement Request: Please extend the API to allow setting of the "last-hop" source process in addition to the original source application. If the last-hop source process info is set, our TP1 can query this property, see that it's coming from our own Helper process, and skip interception. In summary, here are the Enhancement Requests: Allow setMetadata API to work at a socket level Allow setting of "last-hop" source process in the metadata, in addition to the original source application More succinctly, please allow setting of metadata to cater to cases where the actual egress happens via a (different) helper process that uses pure C sockets based API. I have also filed this as a Feedback with Apple, at FB16048393.

I am setting up a fake VPN with proxy settings using NEPacketTunnelProvider. When I check proxy check sites, I can see the proxy is detected. let settings = NEPacketTunnelNetworkSettings(tunnelRemoteAddress: "10.0.0.1") let proxySettings = NEProxySettings() proxySettings.httpEnabled = true proxySettings.httpsEnabled = true proxySettings.httpServer = NEProxyServer(address: hostIP, port: portNumber) proxySettings.httpsServer = NEProxyServer(address: hostIP2, port: portNumber2) proxySettings.excludeSimpleHostnames = false proxySettings.matchDomains = [""] settings.proxySettings = proxySettings How can I control whether other installed apps on the phone use or bypass this proxy? Can I do this with exceptionList? Since I am routing everything through a VPN, I assumed I could control this. The selection of which apps use the proxy should be up to the user. Could you provide an explanation of how I can manage this? I am quite new to these types of tasks.

Hi I'm building a React Native app and need to implement the functionality to connect/disconnect to a VPN using WireGuard configuration files (.conf). I'm using Swift for the native integration on iOS. Does anyone know of any libraries or resources that could help with this?

Our company has a VPN client that we develop and it works on 14.x and it was working on 15.x but ever since I have upgraded to 15.1.1, I do not see any traffic being sent to the TUN interface even though I have it configured as the default route. Can anyone provide guidance or insight into what might have changed around the Network Extensions that could have caused this? Unfortunately I cannot tell if this was happening on 15.0.1. Some things I have tried, to no avail, is disable the firewall and uninstalling/installing of the VPN client. I have no other filters installed that could be interfering. When I try and ping an address I should be able to reach, I get "no route to host" I have also used Wireshark and have observed zero traffic going to the TUN interface. NOTE, networking works fine when the VPN client is not connected.

Can an Persional developer account develop, debug, and publish Network Extension apps?

Hi, i'm working on an endpoint security extension loader and implement several callbacks from delegate object OSSystemExtensionRequestDelegate the callback i'm interested in is : public func request(_ request: OSSystemExtensionRequest, didFinishWithResult result: OSSystemExtensionRequest.Result); public func requestNeedsUserApproval(_ request: OSSystemExtensionRequest); I've noticed that if I manually approve the extension long time after it was activated, the extension process goes up, but the callback isn't being called. The requestNeedUserApproval callback always gets called. I see in the unified logs that when the extension goes from activated_waiting_for_user -> activated_enabling -> activated_enabled Than the request callback doesn't get called. But whenever the extension goes activated_waiting_for_user -> activated_disabled The request callback gets called. (this is counter intuitive since we expected the state activated_disabled may hint that the extension failed to be activated somehow) Any Idea why my callback doesn't gets called if the extension gets approved long after it was activated ?

I have tests where I connect to NEPacketTunnelProvider. I run tests with circleci and fastlane, on self hosted intel and arm macs. I updated macs from macOS 13 to macOS 14 and the tests on arm stopped connecting, while the same tests on intel kept working as usual. Moreover, I noticed the tests don't work when run from circleci and fastlane. If I cancel the job and click "connect" myself on the app that stayed hanging from the cancelled tests, the connection will succeed. But if the tests are running, the connection will fails. Running the tests from xcode succeeds too. These are the logs from the tunnel. Could you suggest me where to dig? Or maybe you can see the issue from the logs? Tunnel logs when they fail

I've been trying very unsuccessfully to get the Filtering Network Traffic example code to work. I've read many forum posts but I still wasn't able to figure it out. I download the example project and set my development team for both targets. From then on the project is configured to create unique bundle identifiers and app group. Signing and provisioning profile is created and managed by Xcode with all the necessary entitlements. I am able to build the app (debug with provisioning profile) and then copy it to /Applications. I open the app, click start, enable and allow the network extension. Activity Monitor shows that the extension is running. But when I test local connections to port 8888 nothing happens in the app, the connection are just allowed. I tested with the following setup: create a local webserver with python3 -m http.server 8888 and make a request via curl and the webbrowser normal tcp connection with nc (nc -l 8888 and nc localhost 8888) I added lots of logging and I can see that the startFilter method is called, but never the handleNewFlow method. The only error I see in Console is networkd_settings_read_from_file Sandbox is preventing this process from reading networkd settings file at "/Library/Preferences/com.apple.networkd.plist", please add an exception. but don't know what to do about that. I also read the debugging guide (very helpful). I'm used to jump through a lot of hoops with this stuff, but I can't figure out what the problem is.

hello, we're currently working on a way to adapt the behavior of our app when the device is running with a low free memory remaining, or a bad network. For the network, we though about implementing a speedtest, but the issue with this solution is that we want to test regularly the quality of the network, so if the device is running with a poor/bad network, the speedtest with stuck the app. I was looking for other way to check the displayed informations in the status bar: private func getWiFiRSSI() -> Int? { let app = UIApplication.shared var rssi: Int? let exception = tryBlock { guard let statusBar = app.value(forKey: "statusBar") as? UIView else { return } if let statusBarMorden = NSClassFromString("UIStatusBar_Modern"), statusBar .isKind(of: statusBarMorden) { return } guard let foregroundView = statusBar.value(forKey: "foregroundView") as? UIView else { return } for view in foregroundView.subviews { if let statusBarDataNetworkItemView = NSClassFromString("UIStatusBarDataNetworkItemView"), view .isKind(of: statusBarDataNetworkItemView) { if let val = view.value(forKey: "wifiStrengthRaw") as? Int { rssi = val break } } } } if let exception = exception { print("getWiFiRSSI exception: \(exception)") } return rssi } I've checked the AppStore Guidelines but I'm not sure that this kind of code will not be subject to rejection by the Review team. Anyone having trying to submit with a similar approach? Did you already managed to monitor network regularly, without using a speedtest? Thanks for the help!

Hi, all. We have a camera with only one WiFi module. It supports AP and STA modes coexisting, but the WiFi of AP and STA can only be in the same channel at the same time, that is, 2.4G or 5G. In the initial state, the App is connected to the camera through 5G WiFi, and the camera is in AP mode. When entering the network configuration mode, the camera will start the STA mode, and the AP and STA modes coexist. When the user selects 2.4G WiFi, the AP mode will switch from 5G to 2.4G. Android's WiFi and socket are not disconnected, iOS's socket will be disconnected 100%, and WiFi may be disconnected. What is the reason for this? Is there any way to solve it?

We have Mac OS VM which has two network interfaces and both are active. In our application we need “State:/Network/Global/IPv6” to do some task but on this machine it seems to be missing, however if we disable one of the interface then the same setting seems to be available and our code works fine. Please find the attached screenshots of working & non-working details: