General: Forums subtopic: App & System Services > Networking DevForums tag: Network Extension Network Extension framework documentation Routing your VPN network traffic article Filtering traffic by URL sample code Filtering Network Traffic sample code TN3120 Expected use cases for Network Extension packet tunnel providers technote TN3134 Network Extension provider deployment technote TN3165 Packet Filter is not API technote Network Extension and VPN Glossary forums post Debugging a Network Extension Provider forums post Exporting a Developer ID Network Extension forums post Network Extension vs ad hoc techniques on macOS forums post NWEndpoint History and Advice forums post Extra-ordinary Networking forums post Wi-Fi management: Wi-Fi Fundamentals forums post TN3111 iOS Wi-Fi API overview technote How to modernize your captive network developer news post iOS Network Signal Strength forums post See also Networking Resources. Share and Enjoy — Quinn “The Eskimo!” @ Developer Technical Support @ Apple let myEmail = "eskimo" + "1" + "@" + "apple.com"

I'm having a lot of trouble just getting a basic network extension startup, I have a main application that creates the configuration and requests the app extension based network extension to launch. The network extension implements a NEPacketTunnelProvider and the application doesn't receive an error when starting the tunnel but when I inspect the networkextension system logs, I keep getting errors and the network extension itself doesn't appear to start nor does it log anything. log stream --predicate 'subsystem == "com.apple.networkextension"' neagent: (NetworkExtension) [com.apple.networkextension:] Extension request with extension $(BUNDLE_ID) started with identifier (null) neagent: (NetworkExtension) [com.apple.networkextension:] Failed to start extension $(BUNDLE_ID): Error Domain=NSCocoaErrorDomain Code=4097 "connection to service named $(BUNDLE_ID)" UserInfo={NSDebugDescription=connection to service named $(BUNDLE_ID)} nesessionmanager: [com.apple.networkextension:] Validation failed - no audit tokens nesessionmanager: [com.apple.networkextension:] NEVPNTunnelPlugin($(BUNDLE_ID)[inactive]): Validation of the extension failed The network extension is written in Objective-C as it needs to integrate with another language. It's not entirely clear what kind of executable the network extension is meant to be, is it meant to have a main entrypoint, or is it supposed to be a shared library / bundle?

As per : TN3120: Expected use cases for Network Extension packet tunnel providers | Apple Developer Documentation It is clear that Packets that are read from NEPacketTunnelFlow are meant to be sent over a tunnel connection to a remote server for injection into a remote network. They are not meant to be dropped or re-injected back into the system. In my usecase: NEPacketTunnelProvider is separate process. which reads the packet using packetFlow.readPacketObjects Send it over to other process i.e privileged helper(Non-bundle/command line tool/non sandboxed) via UDS IPC. Helpers send to to remote tunnel and return back the packet to NEPacketTunnelFlow via same IPC. NEPacketTunnelProvider uses packetFlow.writePacketObjects to inject packets. Things works fine. We don't distribute it via Appstore. We are now attempting to implement a on device bypass mechanism from helper tool side. Could you please suggest if there is any approach I could try, even if it involves proceeding at my own risk?

Description : Our app helps users connect to Wi-Fi hotspots. We are trying to adapt our code to iOS 26 Hotspot Authentication and Hotspot Evaluation application extensions. When filtering hotspots in the filterScanList callback, we need to fetch support information from a remote server to determine which hotspots are supported. However, attempts to use URLSession or NWTCPConnection in the extension always fail. When accessing a URL (e.g., https://www.example.com), the network log shows: Error Domain=NSURLErrorDomain Code=-1003 "A server with the specified hostname could not be found." When accessing a raw IP address, the log shows: [1: Operation not permitted] Interestingly, NWPathMonitor shows the network path as satisfied, indicating that the network is reachable. Question: Are there any missing permissions or misconfigurations on our side, or are we using the wrong approach? Is there an official recommended way to perform network requests from an NEHotspotEvaluationProvider extension?

Hi All, I am currently working on a Network Extension App for MacOS using 3 types of extensions provided by Apple's Network Extension Framework. Content Filter, App Proxy (Want to get/capture/log all HTTP/HTTPS traffic), DNS Proxy (Want to get/capture/log all DNS records). Later parse into human readable format. Is my selection of network extension types correct for the intended logs I need? I am able to run with one extension: Main App(Xcode Target1) <-> Content Filter Extension. Here there is a singleton class IPCConnection between App(ViewController.swift) which is working fine with NEMachServiceName from Info.plist of ContentFilter Extension(Xcode Target2) However, when I add an App Proxy extension as a new Xcode Target3, I think the App and extension's communication getting messed up and App not getting started/Crashing. Here, In the same Main App, I am adding new separate IPCConnection for this extension. Here is the project organization/folder structure. MyNetworkExtension ├──MyNetworkExtension(Xcode Target1) │ ├── AppDelegate.swift │ ├── Assets.xcassets │ ├── Info.plist │ ├── MyNetworkExtension.entitlement │ | ── Main │ |-----ViewController.swift │ └── Base.lproj │ └── Main.storyboard ├── ContentFilterExtension(Xcode Target2) │ ├── ContentFilterExtension.entitlement │ │ ├── FilterDataProvider.swift │ │ ├── Info.plist │ │ ├── IPCConnection.swift │ │ └── main.swift ├── AppProxyProviderExtension(Xcode Target3) │ ├── AppProxyProviderExtension.entitlement │ │ ├── AppProxyIPCConnection.swift │ │ ├── AppProxyProvider.swift │ │ ├── Info.plist │ │ └── main.swift └── Frameworks ├── libbsm.tbd └── NetworkExtension.framework Is my Approach for creating a single Network Extension App with Multiple extensions correct or is there any better approach of project organization that will make future modifications/working easier and makes the maintenance better? I want to keep the logic for each extension separate while having the same, single Main App that manages everything(installing, activating, managing identifiers, extensions, etc). What's the best approach to establish a Communication from MainApp to each extension separately, without affecting one another? Is it good idea to establish 3 separate IPC Connections(each is a singleton class) for each extension? Are there any suggestions you can provide that relates to my use case of capturing all the network traffic logs(including HTTP/HTTPS, DNS Records, etc), especially on App to Extension Communication, where my app unable to keep multiple IPC Connections and maintain them separately? I've been working on it for a while, and still unable to make the Network Extension App work with multiple extensions(each as a new Xcode target). Main App with single extension is working fine, but if I add new extension, App getting crashed. I suspect it's due to XPC/IPC connection things! I really appreciate any support on this either directly or by any suggestions/resources that will help me get better understand and make some progress. Please reach out if in case any clarifications or specific information that's needed to better understand my questions. Thank you very much

Hello, I've been experimenting with the new NEURLFilter API and so far the results are kind of strange. SimpleURLFilter sample contains a bloom filter that seems to be built from this dataset in pir-service-example. I was able to run SimpleURLFilter sample and configure it to use PIRService from the example repo. I also observed the requests that iOS has been sending: requesting config and then sending /queries request. What I haven't seen is any .deny verdict for any URL. Even when calling NEURLFilter.verdict(for: url) directly I cannot see a .deny verdict. Is there anything wrong with the sample or is there a known issue with NEURLFilter in the current beta (beta 8) that prevents it from working?

Hello Apple Developer Community, We are developing a full-tunnel VPN app for macOS that utilizes a packet tunnel network system extension (via NEPacketTunnelProvider). We're committed to using a system extension for this purpose, as it aligns with our requirements for system-wide tunneling. The app is sandboxed and intended for distribution on the Mac App Store. Here's the workflow: The app (running in user context) downloads a VPN profile from our server. It generates private keys, appends them to the profile, and attempts to save this enhanced profile securely in the keychain. The packet tunnel system extension (running in root context) needs to access this profile, including the private keys, to establish the VPN connection. We've encountered challenges in securely sharing this data across the user-root boundary due to sandbox restrictions and keychain access limitations. Here's what we've tried so far, along with the issues: Writing from the App to the System Keychain: Attempted to store the profile in the system keychain for root access. This fails because the sandboxed app lacks permissions to write to the system keychain. (We're avoiding non-sandboxed approaches for App Store compliance.) Extension Reading Directly from the User Login Keychain: Tried having the extension access the user's login keychain by its path. We manually added the network extension (located in /Library/SystemExtensions//bundle.systemextension) to the keychain item's Access Control List (ACL) via Keychain Access.app for testing. This results in "item not found" errors, likely due to the root context not seamlessly accessing user-keychain items without additional setup. Using Persistent References in NETunnelProviderProtocol: The app stores the profile in the user keychain and saves a persistent reference (as Data) in the NETunnelProviderProtocol's identityReference or similar fields. The extension then attempts to retrieve the item using this reference. We manually added the network extension (located in /Library/SystemExtensions//bundle.systemextension) to the keychain item's Access Control List (ACL) via Keychain Access.app for testing. However, this leads to error -25308 (errSecInteractionNotAllowed) when the extension tries to access it, possibly because of the root-user context mismatch or interaction requirements. Programmatically Adding the Extension to the ACL: Explored using SecAccess and SecACL APIs to add the extension as a trusted application. This requires SecTrustedApplicationCreateFromPath to create a SecTrustedApplicationRef from the extension's path. Issue 1: The sandboxed app can't reliably obtain the installed extension's path (e.g., via scanning /Library/SystemExtensions or systemextensionsctl), as sandbox restrictions block access. Issue 2: SecTrustedApplicationCreateFromPath is deprecated since macOS 10.15, and we're hesitant to rely on it for future compatibility. We've reviewed documentation on keychain sharing, access groups (including com.apple.managed.vpn.shared, but we're not using managed profiles/MDM) as the profiles are download from a server, and alternatives like XPC for on-demand communication, but we're unsure if XPC is suitable for sensitive data like private keys during tunnel creation. And if this is recommended what is going to be the approach here. What is the recommended, modern approach for this scenario? Is there a non-deprecated way to handle ACLs or share persistent references across contexts? Should we pursue a special entitlement for a custom access group, or is there a better pattern using NetworkExtension APIs? Any insights, code snippets, or references to similar implementations would be greatly appreciated. We're targeting macOS 15+. Thanks in advance!

Hi everyone, I'm having trouble with Network Extensions capability not being included in my provisioning profiles. Here's my setup: Environment: Xcode 16.0 iOS Deployment Target: 17.0 Paid Apple Developer Program ($99/year) Problem: I'm trying to use NEHotspotConfiguration in my app, but getting this error: entitlement What I've done: ✅ Enabled "Network Extensions" in App ID capabilities ✅ Enabled "Access Wi-Fi Information" and "Hotspot" ✅ Created new provisioning profiles after enabling capabilities ✅ Cleaned build folder and rebuilt ✅ Using "Automatically manage signing" in Xcode Current status: App ID shows all capabilities are enabled Xcode shows Network Extensions capability is present But provisioning profiles still don't include the entitlement NEHotspotConfiguration fails with entitlement error Questions: Has anyone else experienced this issue? Is there a specific way to force Xcode to include the entitlement? Should I try manual provisioning profile creation? Are there any known bugs with Network Extensions in Xcode 16? Code I'm trying to use: } Any help would be greatly appreciated! Thanks,

NEAppProxyUDPFlow contains below property: open var localEndpoint: NWEndpoint? { get } Why is localEndpoint not available for NEAppProxyTCPFlow? Is there a way to determine the source port of a flow of type NEAppProxyTCPFlow within the following method of NETransparentProxyProvider? override func handleNewFlow(_ flow: NEAppProxyFlow) -> Bool {

The Wi‑Fi Alliance’s Wi‑Fi Aware data communication uses IPv6. However, in Chapter 53 “Wi‑Fi Aware” of the Accessory Design Guidelines for Apple Devices, Release R26, it is stated that “The Neighbor Discovery Protocol (NDP) for IPv6 address resolution is not supported.” This has caused confusion among developers: Does Apple’s Wi‑Fi Aware data communication actually use IPv6? What is the impact of “The Neighbor Discovery Protocol (NDP) for IPv6 address resolution is not supported” in Apple’s implementation?

We currently supporting proxy app with Tunnel.appEx and PacketTunnelProvider. Some users report about constant error "The VPN session failed because an internal error occurred." on VPN start (which fails rapidly). This error occur mostly after user updated app with active VPN. Rebooting device solves the problem and it doesnt come again, but it is still very frustrating. I can provide any required info about app setup to solve this issue if you need. Thanks

In Low Power Mode or after the iPhone has been idle, On-Demand rules fire and StartTunnel runs. Subsequent calls to createTCPConnectionThroughTunnel intermittently fail with an error. Is NetworkExtension known to behave differently under Low Power Mode that might cause this?

I cannot find in the documentation and samples how exactly the Bloom filter is generated. Is there any code sample for that?

Apple is encouraging VPN apps on macOS to transition to Network Extension APIs, if they haven't done so yet, see: TN3165: Packet Filter is not API WWDC25: Filter and tunnel network traffic with NetworkExtension Using Network Extension is fine for VPN apps that are distributed via the Mac App Store. Users get one pop-up requesting permission to add VPN configurations and that's it. However, VPN apps that are distributed outside of the App Store (using Developer ID) cannot use Network Extension in the same way, such apps need to install a System Extension first (see TN3134: Network Extension provider deployment). Installing a System Extension is a very poor user experience. There is a pop-up informing about a system extension, which the user has to manually enable. The main button is "OK", which only dismisses the pop-up and in such case there is little chance that the user will be able to find the correct place to enable the extension. The other button in that pop-up navigates to the correct screen in System Settings, where the user has to enable a toggle. Then there is a password prompt. Then the user has to close the System Settings and return to the app. This whole dance is not necessary for VPN apps on the Mac App Store, because they work with "app extensions" rather than "system extensions". As a developer of a VPN app that is distributed outside of the App Store, my options are: Implement VPN functionality in an alternative way, without Network Extension. This is discouraged by Apple. Use a System Extension with Network Extension. This is going to discourage my users. I have submitted feedback to Apple: FB19631390. But I wonder, why did Apple create this difference in the first place? Is there a chance that they will either improve the System Extension installation process or even allow "app extensions" outside of the Mac App Store?

I filed FB19631435 about this just now. Basically: starting with 15.6, we've had reports (internally and outternally) that after some period of time, networking fails so badly that it can't even acquire a DHCP lease, and the system needs to be rebooted to fix this. The systems in question all have at least 2 VPN applications installed; ours is a transparent proxy provider, and the affected system also had Crowdstrike's Falcon installed. A customer system reported seemingly identical failures on their systems; they don't have Crowdstrike, but they do have Cyberhaven's. Has anyone else seen somethng like this? Since it seems to involve three different networking extensions, I'm assuming it's due to an interaction between them, not a bug in any individual one. But what do I know? 😄

We have an application which is written in Swift, which activates Transparent Proxy network extension. Our Transparent Proxy module is a system extension, which is exposing an app proxy provider interface (We are using NETransparentProxyProvider class and in extension’s Info.plist we use com.apple.networkextension.app-proxy key.) We are using JAMF MDM profile for installing our transparent proxy in customer environment. We are using VPN payload(https://developer.apple.com/documentation/devicemanagement/vpn) for this network system extension. This payload does not have any field for order. As per https://developer.apple.com/documentation/devicemanagement/vpn/transparentproxy-data.dictionary documentation there is another payload for TransparentProxy and we could create a Transparent Proxy profile using iMazingProfile Editor. Noticed that, if we add the Order attribute to the VPN/TransparentProxy payload, while installing the extension, the save to preferences fails with "Error in saving TP configuration in updateOnDemandRule permission denied" error. Can we use this Order field to ordering the installed Transparent Proxy extension in a machine? Customer devices will likely have other Transparent Proxy network extensions as well. We want to allow the Customer to control the order in which each Transparent Proxy network extension receives the network traffic. How can we set the order of the Transparent proxy extension that can be deployed using MDM profile with VPN/TransparentProxy payload? Attached the TransparentProxy payload profile for the reference. DGWebProxy_TransparentProxy_iMazing

I'm trying to distribute a sandboxed macOS app with a PacketTunnelProvider (system extension) via direct distribution (outside of AppStore). The app and the extension both use the same app group, using the new group.com.XXXX.YYYY format detailed here for 10.15+ https://developer.apple.com/forums/thread/721701 I've also followed the instructions below to get around the quirk of not being able to directly process it via XCode: https://developer.apple.com/forums/thread/737894 I've re-signed with Developer ID certificate, all that is smooth and successfully notarized. However upon running the app I get: "My.app" would like to access data from other apps. Checking ~/Library/Containers ~/Library/Group Containers I see the correct files folders have been created before I select Don't Allow and Allow. My app does not access any files or folders outside of the sandboxed directories. How can I prevent this from happening? In order to diagnose further, how to diagnose exactly which files/folder the app is trying to access that is causing this problem?

Hello, We're exploring the new URL Filter capability and we managed change the SimpleURLFilter so that it could work on macOS. However, on macOS it won't work as even when signed for debugging it tries to use Apple's OHTTP Relay. Failed to fetch Token Issuer Directory. <NSHTTPURLResponse: 0xca10ca580> { URL: https://gateway.icloud.com/pat-issuer-directory?issuer=localhost } { Status Code: 503 So I have two questions: Will it be possible to debug URL Filter locally on macOS? Even more important: how can I send a capability request so that our OHTTP Gateway could be used? I checked everywhere, but it seems there's simply no way to request this capability at this moment.

Hi everyone, I’m currently developing a macOS app that is distributed via a DMG file on our website. The app includes an App Extension (appex) for Network Extension functionality. I’m wondering if distributing via DMG on the web requires the app extension to be implemented as a System Extension instead of an App Extension. Is it necessary to migrate to System Extension for web-based DMG distribution, or can I continue using App Extension as is? Any insights or recommendations would be greatly appreciated. Thank you!

With my UDP Flow Copier working as demonstrated by the fact that it is proxying DNS traffic successfully, I am finally writing tests to verify UDP packet filtering. I'm sending packets to a public UDP echo server and reading the response successfully. In my initial testing however the TransparentProxyProvider System Extension is not intercepting my UDP traffic. handleNewUDPFlow() is being called for DNS but not for my test case UDP echo sends and receives. I've tried sending UDP with both GCDAsyncSocket and NWConnection as: connection = NWConnection(host: host, port: port, using: .udp) Is there some other criteria for UDP datagrams to be intercepted? Google search suggests this might be a known issue for connected or async UDP sockets.

We are currently developing a VoIP application that supports Local Push extention. We discovered an issue with this app where the performEndCallAction response to reportCallWithUUID is occasionally slow.(See below for detail) It usually works without any issues, so we believe there is no problem with the app's processing flow. This issue only occurs very rarely, but each time it does there is a delay of about 60 seconds, which leads us to suspect that there is some kind of problem on the iOS side, and that fail-safe processing is occurring after 60 seconds. Do you know of a workaround for this issue?