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XPC listener initialized in System Extesnion invalidates incoming connection under certain conditions
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.
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1.4k
Apr ’25
SSL certificate failure
This problem doesn’t appear to relate to the app as everything worked when using http (although an https setup issue may still be the problem). The problem appears to relate to the SSL server certificate on the Ubuntu server and the fact that apple does not accept that it is secure. However I have no problem with the equivalent Android app or web browser connections to the same rest API web services. There are numerous posts on these problems on Apple and other Forums, but none have helped me successfully address the issue. I ran an SSL server test on https://www.ssllabs.com/ssltest/ which gives ratings for SSL sites. The test gave an A rating although a number of minor issues were shown that may be crucial to the iOS failure. Some Sectigo certificates said self signed, which I couldn't understand. Error message from XCode log attached 2025-09-10 10:28:01.725091+0100 locateandclock[2291:1585213] ATS failed system trust 2025-09-10 10:28:01.725192+0100 locateandclock[2291:1585213] Connection 1: system TLS Trust evaluation failed(-9802) 2025-09-10 10:28:01.725291+0100 locateandclock[2291:1585213] Connection 1: TLS Trust encountered error 3:-9802 2025-09-10 10:28:01.725352+0100 locateandclock[2291:1585213] Connection 1: encountered error(3:-9802) 2025-09-10 10:28:01.726727+0100 locateandclock[2291:1585213] Task <4E41098F-6B71-4FB8-8753-78DD32961812>.<1> HTTP load failed, 0/0 bytes (error code: -1200 [3:-9802]) 2025-09-10 10:28:01.736504+0100 locateandclock[2291:1585213] Task <4E41098F-6B71-4FB8-8753-78DD32961812>.<1> finished with error [-1200] Error Domain=NSURLErrorDomain Code=-1200 "An SSL error has occurred and a secure connection to the server cannot be made." UserInfo={NSLocalizedRecoverySuggestion=Would you like to connect to the server anyway?, _kCFStreamErrorDomainKey=3, NSErrorPeerCertificateChainKey=( "<cert(0x10681be00) s: *.xxxxxxxxxxx.co.uk i: Sectigo Public Server Authentication CA DV R36>", "<cert(0x10681c800) s: Sectigo Public Server Authentication CA DV R36 i: Sectigo Public Server Authentication Root R46>", "<cert(0x10681d200) s: Sectigo Public Server Authentication Root R46 i: Sectigo Public Server Authentication Root R46>" ), NSErrorClientCertificateStateKey=0, NSErrorFailingURLKey=https://xxxxxxxxxxxx.co.uk/insertclocking, NSErrorFailingURLStringKey=https://xxxxxxxxxxxx.co.uk/insertclocking, NSUnderlyingError=0x282361650 {Error Domain=kCFErrorDomainCFNetwork Code=-1200 "(null)" UserInfo={_kCFStreamPropertySSLClientCertificateState=0, kCFStreamPropertySSLPeerTrust=<SecTrustRef: 0x281cf4460>, _kCFNetworkCFStreamSSLErrorOriginalValue=-9802, _kCFStreamErrorDomainKey=3, _kCFStreamErrorCodeKey=-9802, kCFStreamPropertySSLPeerCertificates=( "<cert(0x10681be00) s: *.xxxxxxxxxxxxxco.uk i: Sectigo Public Server Authentication CA DV R36>", "<cert(0x10681c800) s: Sectigo Public Server Authentication CA DV R36 i: Sectigo Public Server Authentication Root R46>", "<cert(0x10681d200) s: Sectigo Public Server Authentication Root R46 i: Sectigo Public Server Authentication Root R46>" )}}, _NSURLErrorRelatedURLSessionTaskErrorKey=( "LocalDataTask <4E41098F-6B71-4FB8-8753-78DD32961812>.<1>" ), _kCFStreamErrorCodeKey=-9802, _NSURLErrorFailingURLSessionTaskErrorKey=LocalDataTask <4E41098F-6B71-4FB8-8753-78DD32961812>.<1>, NSURLErrorFailingURLPeerTrustErrorKey=<SecTrustRef: 0x281cf4460>, NSLocalizedDescription=An SSL error has occurred and a secure connection to the server cannot be made.}
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301
Oct ’25
NetworkConnection throws EINVAL when receiving ping/pong control frames
Summary NetworkConnection<WebSocket> in iOS 26 Network framework throws POSIXErrorCode(rawValue: 22): Invalid argument when receiving WebSocket ping (opcode 9) or pong (opcode 10) control frames. This prevents proper WebSocket keep-alive functionality. Environment iOS 26.0 (Simulator) macOS 26.1 Xcode 26.0 Note: This issue was initially discovered on iOS 26 Simulator. The same behavior was confirmed on macOS 26, suggesting a shared bug in the Network framework. The attached sample code is for macOS for easier reproduction. Description When using the new NetworkConnection<WebSocket> API introduced in iOS 26 or macOS 26, the receive() method throws EINVAL error whenever a ping or pong control frame is received from the server. This is a critical issue because: WebSocket servers commonly send ping frames to keep connections alive Clients send ping frames to verify connection health The receive callback never receives the ping/pong frame - the error occurs before the frame reaches user code Steps to Reproduce Create a WebSocket connection to any server that supports ping/pong (e.g., wss://echo.websocket.org): import Foundation import Network // MARK: - WebSocket Ping/Pong EINVAL Bug Reproduction // This sample demonstrates that NetworkConnection<WebSocket> throws EINVAL // when receiving ping or pong control frames. @main struct WebSocketPingPongBug { static func main() async { print("=== WebSocket Ping/Pong EINVAL Bug Reproduction ===\n") do { try await testPingPong() } catch { print("Test failed with error: \(error)") } } static func testPingPong() async throws { let host = "echo.websocket.org" let port: UInt16 = 443 print("Connecting to wss://\(host)...") let endpoint = NWEndpoint.hostPort( host: NWEndpoint.Host(host), port: NWEndpoint.Port(rawValue: port)! ) try await withNetworkConnection(to: endpoint, using: { WebSocket { TLS { TCP() } } }) { connection in print("Connected!\n") // Start receive loop in background let receiveTask = Task { var messageCount = 0 while !Task.isCancelled { do { let (data, metadata) = try await connection.receive() messageCount += 1 print("[\(messageCount)] Received frame - opcode: \(metadata.opcode)") if let text = String(data: data, encoding: .utf8) { print("[\(messageCount)] Content: \(text)") } else { print("[\(messageCount)] Binary data: \(data.count) bytes") } } catch let error as NWError { if case .posix(let code) = error, code == .EINVAL { print("❌ EINVAL error occurred! (POSIXErrorCode 22: Invalid argument)") print(" This is the bug - ping/pong frame caused EINVAL") // Continue to demonstrate workaround continue } print("Receive error: \(error)") break } catch { print("Receive error: \(error)") break } } } // Wait for initial message from server try await Task.sleep(for: .seconds(2)) // Test 1: Send text message (should work) print("\n--- Test 1: Sending text message ---") try await connection.send("Hello, WebSocket!") print("✅ Text message sent") try await Task.sleep(for: .seconds(1)) // Test 2: Send ping (pong response will cause EINVAL) print("\n--- Test 2: Sending ping frame ---") print("Expecting EINVAL when pong is received...") let pingMetadata = NWProtocolWebSocket.Metadata(opcode: .ping) try await connection.ping(Data()) { pingMetadata } print("✅ Ping sent, waiting for pong...") // Wait for pong response try await Task.sleep(for: .seconds(2)) // Cleanup receiveTask.cancel() print("\n=== Test Complete ===") print("If you saw 'EINVAL error occurred!' above, the bug is reproduced.") } } } The receive() call fails with error when pong arrives: ❌ EINVAL error occurred! (POSIXErrorCode 22: Invalid argument) Test Results Scenario Result Send/receive text (opcode 1) ✅ OK Client sends ping, receives pong ❌ EINVAL on pong receive Expected Behavior The receive() method should successfully return ping and pong frames, or at minimum, handle them internally without throwing an error. The autoReplyPing option should allow automatic pong responses without disrupting the receive loop. Actual Behavior When a ping or pong control frame is received: The receive() method throws NWError.posix(.EINVAL) The frame never reaches user code (no opcode check is possible) The connection remains valid, but the receive loop is interrupted Workaround Catch the EINVAL error and restart the receive loop: while !Task.isCancelled { do { let received = try await connection.receive() // Process message } catch let error as NWError { if case .posix(let code) = error, code == .EINVAL { // Control frame caused EINVAL, continue receiving continue } throw error } } This workaround allows continued operation but: Cannot distinguish between ping-related EINVAL and other EINVAL errors Cannot access the ping/pong frame content Cannot implement custom ping/pong handling Impact WebSocket connections to servers that send periodic pings will experience repeated EINVAL errors Applications must implement workarounds that may mask other legitimate errors Additional Information Packet capture confirms ping/pong frames are correctly transmitted at the network level The error occurs in the Network framework's internal processing, before reaching user code
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275
Dec ’25
Network Extension – Delayed Startup Time
I've implemented a custom VPN system extension for macOS, utilizing Packet Tunnel Provider. One of the users reported a problem: he was connected to the VPN, and then his Mac entered sleep mode. Upon waking, the VPN is supposed to connect automatically (because of the on-demand rules). The VPN's status changed to 'connecting', but it remained stuck in this status. From my extension logs, I can see that the 'startTunnelWithOption()' function was called 2 minutes after the user clicked the 'connect' button. From the system logs, I noticed some 'suspicious' logs, but I can't be sure if they are related to the problem. Some of them are: kernel: (Sandbox) Sandbox: nesessionmanager(562) deny(1) system-fsctl (_IO "h" 47) entitlement com.apple.developer.endpoint-security.client not present or not true (I don't need this entitlement at the extension) nesessionmanager: [com.apple.networkextension:] NESMVPNSession[Primary Tunnel:XXXXXX(null)]: Skip a start command from YYYYY:session in state connecting NetworkExtension.com.***: RunningBoard doesn't recognize submitted process - treating as a anonymous process sysextd: activateDecision found existing entry of same version: state activated_enabled, ID FAE... Are any of the logs related to the above problem? How can I debug such issues? What info should I get from the user?
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299
Oct ’25
WebAuthenticationSession under a carrier-provided satellite network?
(related post: How to optimize my app for for a carrier-provided satellite network? ) I am trying to implement an app so that it works under a carrier-provided satellite network. The app uses (AS)WebAuthenticationSession for signing in. If the app is entitled to access a satellite network, will (AS)WebAuthenticationSession work as well? How about WKWebView and SFSafariViewController? Is there a way to test(simulate) a ultra-constrained network on a device or a simulator to see the expected behavior? Thanks,
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450
Jul ’25
DNS Resolution fails in 15.4
Hi, DNS resolution using libresolv (res_nquery) fails in 15.4 when connected to VPN. The same is working fine for 15.3 and lower and this happens for all the domains. The method returns -1 and res->res_h_errno is set to 2. In wireshark we can see that the DNS request is sent and server also returns the response successfully. The same works fine if we use TCP instead of UDP by setting the following option res->options |= RES_USEVC;
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225
Apr ’25
XPC connection consistently invalidated on app upgrade
Hi, Our project is a MacOS SwiftUI GUI application that bundles a System Network Extension, signed with a Developer ID certificate for distribution outside of the app store. The system network extension is used to write a packet tunnel provider. The signing of the app & network extension is handled by XCode (v16.0.0), we do not run codesign ourselves. We have no issues with XPC or the system network extension during normal usage, nor when the application is installed on a user's device for the first time. The problem only arises when the user upgrades the application. I have experienced this issue myself, as have our users. It's been reported on Apple Silicon macbooks running at least macOS 15.3.2. Much like the SimpleFirewall example (which we used as a reference), we use XPC for basic communication of state between the app and NE. These XPC connections stop working when the user installs a new version of the app, with OS logs from the process indicating that the connection is immediately invalidated. Subsequent connection attempts are also immediately invalidated. Toggling the VPN in system settings (or via the app) does not resolve the problem, nor does restarting the app, nor does deleting and reinstalling the app, nor does restarting the device. The only reliable workaround is to delete the system extension in Login Items & Extensions, under Network Extensions. No device restart is necessary to garbage collect the old extension - once the extension is reapproved by the user, the XPC issue resolves itself. This would be an acceptable workaround were it possible to automate the deleting of the system extension, but that appears deliberately not possible, and requiring our users to do this each time they update is unreasonable. When the upgraded app is opened for the first time, the OSSystemExtensionRequest request is sent, and the outcome is that the previously installed system network extension is replaced, as both the CFBundleVersion and CFBundleShortVersionString differ. When this issue is encountered, the output of systemextensionsctl list shows the later version is installed and activated. I've been able to reproduce this bug on my personal laptop, with SIP on and systemextensionsctl developer off, but on my work laptop with SIP off and systemextensionsctl developer on (where the network extension is replaced on each activation request, instead of only when the version strings differ), I do not encounter this issue, which leads me to believe it has something to do with the notarization process. We notarize the pkg using xcrun notarytool, and then staple to the pkg. This is actually the same issue described in: https://developer.apple.com/forums/thread/711713 https://developer.apple.com/forums/thread/667597 https://developer.apple.com/forums/thread/742992 https://developer.apple.com/forums/thread/728063 but it's been a while since any of these threads were updated, and we've made attempts to address it off the suggestions in the threads to no avail. Those suggestions are: Switching to a .pkg installer from a .dmg As part of the .pkg preinstall, doing all of the following: Stopping the VPN (scutil --nc stop), shutting down the app (using osascript 'quit app id'), and deleting the app (which claims to delete the network extension, but not the approval in Login Items & Extensions remains??), by running rm -rf on the bundle in /Applications As part of the .pkg postinstall: Forcing macOS to ingest the App bundle's notarization ticket using spctl --assess. Ensuring NSXPCListener.resume() is called after autoreleasepool { NEProvider.startSystemExtensionMode() } (mentioned in a forum thread above as a fix, did not help.) One thing I'm particularly interested in is the outcome of this feedback assistant ticket, as I can't view it: FB11086599. It was shared on this forum in the first thread above, and supposedly describes the same issue. I almost find it hard to believe that this issue has been around for this many years without a workaround (there's system network extension apps out there that appear to work fine when updating, are they not using XPC?), so I wonder if there's a fix described in that FB ticket. Since I can't view that above feedback ticket, I've created my own: FB17032197
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421
Jun ’25
Need Inputs on Which Extension to Use
Hi all, I have a working macOS (Intel) system extension app that currently uses only a Content Filter (NEFilterDataProvider). I need to capture/log HTTP and HTTPS traffic in plain text, and I understand NETransparentProxyProvider is the right extension type for that. For HTTPS I will need TLS inspection / a MITM proxy — I’m new to that and unsure how complex it will be. For DNS data (in plain text), can I use the same extension, or do I need a separate extension type such as NEPacketTunnelProvider, NEFilterPacketProvider, or NEDNSProxyProvider? Current architecture: Two Xcode targets: MainApp and a SystemExtension target. The SystemExtension target contains multiple network extension types. MainApp ↔ SystemExtension communicate via a bidirectional NSXPC connection. I can already enable two extensions (Content Filter and TransparentProxy). With the NETransparentProxy, I still need to implement HTTPS capture. Questions I’d appreciate help with: Can NETransparentProxy capture the DNS fields I need (dns_hostname, dns_query_type, dns_response_code, dns_answer_number, etc.), or do I need an additional extension type to capture DNS in plain text? If a separate extension is required, is it possible or problematic to include that extension type (Packet Tunnel / DNS Proxy / etc.) in the same SystemExtension Xcode target as the TransparentProxy? Any recommended resources or guidance on TLS inspection / MITM proxy setup for capturing HTTPS logs? There are multiple DNS transport types — am I correct that capturing DNS over UDP (port 53) is not necessarily sufficient? Which DNS types should I plan to handle? I’ve read that TransparentProxy and other extension types (e.g., Packet Tunnel) cannot coexist in the same Xcode target. Is that true? Best approach for delivering logs from multiple extensions to the main app (is it feasible)? Or what’s the best way to capture logs so an external/independent process (or C/C++ daemon) can consume them? Required data to capture (not limited to): All HTTP/HTTPS (request, body, URL, response, etc.) DNS fields: dns_hostname, dns_query_type, dns_response_code, dns_answer_number, and other DNS data — all in plain text. I’ve read various resources but remain unclear which extension(s) to use and whether multiple extension types can be combined in one Xcode target. Please ask if you need more details. Thank you.
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304
Jan ’26
Network Push Provider Wifi Selection Behavior
In our App, we have a network extension with a NEAppPushProvider subclass running. We run the following steps Setup a dual-band wireless router per the following: Broadcasting 2.4 GHz and 5 GHz channels Same SSID names for both channels Connected to the production network to the router DHCP assigning addresses in the 10.1.x.x network Connect the mobile device to the 5 GHz network (if needed, turn off the 2.4 GHz network temporarily; once the device connects to the 5 GHz network, the 2.4 GHz network can be turned back on). Create a NEAppPushManager in the App, using the SSID from the above mentioned network and set it to the matchSSIDs property. Call saveToPreferences() on the push manager to save. A. We have UI that shows the extension has been started and it has connected to the server successfully. Walk out of the range of the 5 GHz channel of the router, but stay within range of the 2.4ghz channel. Wait for the mobile device to connect to the 2.4 GHz channel. Expected: The extension would reconnect to the 2.4ghz network. Observed: The extension does not reconnect. Checking the logs for the extension we see that the following was called in the push provider subclass. stop(with:completionHandler:) > PID: 808 | 🗒️🛑 Stopped with reason 3: "noNetworkAvailable" The expectation is that start() on the NEAppPushProvider subclass would be called. Is this an incorrect expectation? How does the NEAppPushProvider handle same network SSID roaming among various band frequencies? I looked at the documentation and did not find any settings targeting 2.4 or 5 ghz networks. Please advise on what to do.
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144
Apr ’25
Running headless app as root for handling VPN and launching microservices
Hello to all I have coded in swift a headless app, that launches 3 go microservices and itself. The app listens via unix domain sockets for commands from the microservices and executes different VPN related operations, using the NEVPNManager extension. Because there are certificates and VPN operations, the headless app and two Go microservices must run as root. The app and microservices run perfectly when I run in Xcode launching the swift app as root. However, I have been trying for some weeks already to modify the application so at startup it requests the password and runs as root or something similar, so all forked apps also run as root. I have not succeeded. I have tried many things, the last one was using SMApp but as the swift app is a headless app and not a CLI command app it can not be embedded. And CLI apps can not get the VPN entitlements. Can anybody please give me some pointers how can I launch the app so it requests the password and runs as root in background or what is the ideal framework here? thank you again.
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384
Dec ’25
How to restore macOS routing table after VPN crash or routing changes?
Hi, I have a VPN product for macOS. When activated, it creates a virtual interface that capture all outgoing traffic for the VPN. the VPN encrypt it, and send it to the tunnel gateway. The gateway then decapsulates the packet and forwards it to the original destination. To achieve this, The vpn modifies the routing table with the following commands: # after packets were encoded with the vpn protocol, re-send them through # the physical interface /sbin/route add -host <tunnel_gateway_address_in_physical_subnet> <default_gateway> -ifp en0 > /dev/null 2>&1 # remove the default rule for en0 and replace it with scoped rule /sbin/route delete default <default_gateway> -ifp en0 > /dev/null 2>&1 /sbin/route add default <default_gateway> -ifscope en0 > /dev/null 2>&1 # create new rule for the virtual interface that will catch all packets # for the vpn /sbin/route add default <tunnel_gateway_address_in_tunnel_subnet> -ifp utunX > /dev/null 2>&1 This works in most cases. However, there are scenarios where the VPN process may crash, stop responding, or another VPN product may alter the routing table. When that happens, packets may no longer go out through the correct interface. Question: Is there a way to reliably reconstruct the routing table from scratch in such scenarios? Ideally, I would like to rebuild the baseline rules for the physical interface (e.g., en0) and then reapply the VPN-specific rules on top. Are there APIs, system utilities, or best practices in macOS for restoring the original routing configuration before reapplying custom VPN routes? Thanks
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439
Sep ’25
Change includeAllNetworks from NetworkExtension while tunnel is running
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
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1k
Mar ’25
Can NWConnection.receive(minimumIncompleteLength:maximumLength:) return nil data for UDP while connection remains .ready?
I’m using Network Framework with UDP and calling: connection.receive(minimumIncompleteLength: 1, maximumLength: 1500) { data, context, isComplete, error in ... // Some Logic } Is it possible for this completion handler to be called with data==nil if I haven't received any kind of error, i.e., error==nil and the connection is still in the .ready state?
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152
3w
Network System Extension cannot use network interface of another VPN
Hi, Our project is a MacOS SwiftUI GUI application that bundles a (Sandboxed) System Network Extension, signed with a Developer ID certificate for distribution outside of the app store. The system network extension is used to write a packet tunnel provider (NEPacketTunnelProvider), as our project requires the creation of a TUN device. In order for our System VPN to function, it must reach out to a (self-hosted) server (i.e. to discover a list of peers). Being self-hosted, this server is typically not accessible via the public web, and may only be accessible from within a VPN (such as those also implemented using NEPacketTunnelProvider, e.g. Tailscale, Cloudflare WARP). What we've discovered is that the networking code of the System Network Extension process does not attempt to use the other VPN network interfaces (utunX) on the system. In practice, this means requests to IPs and hostnames that should be routed to those interfaces time out. Identical requests made outside of the Network System Extension process use those interfaces and succeed. The simplest example is where we create a URLSession.downloadTask for a resource on the server. A more complicated example is where we execute a Go .dylib that continues to communicate with that server. Both types of requests time out. Two noteworthy logs appear when packets fail to send, both from the kernel 'process': cfil_hash_entry_log:6088 <CFIL: Error: sosend_reinject() failed>: [30685 com.coder.Coder-Desktop.VPN] <UDP(17) out so b795d11aca7c26bf 57728068503033955 57728068503033955 age 0> lport 3001 fport 3001 laddr 100.108.7.40 faddr 100.112.177.88 hash 58B15863 cfil_service_inject_queue:4472 CFIL: sosend() failed 49 I also wrote some test code that probes using a UDP NWConnection and NWPath availableInterfaces. When run from the GUI App, multiple interfaces are returned, including the one that routes the address, utun5. When ran from within the sysex, only en0 is returned. I understand routing a VPN through another is unconventional, but we unfortunately do need this functionality one way or another. Is there any way to modify which interfaces are exposed to the sysex? Additionally, are these limitations of networking within a Network System Extension documented anywhere? Do you have any ideas why this specific limitation might exist?
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2
411
Jul ’25
iPhone 17(iOS26) Unable to join the Wi-Fi(TKIP)
Device: iPhone 17 Series System: iOS 26.0.0 Wi-Fi: TKIP encryption protocol Question: Unable to join the network We have several products that are used by connecting to iPhone via Wi-Fi. Recently, many customers who have purchased the iPhone 17 series have reported that they are unable to connect to Wi-Fi. For Wi-Fi with TKIP encryption, after entering the password correctly to connect to the Wi-Fi, a pop-up appears stating "Unable to join the network.". Only Wi-Fi with WPA2-AES can be used normally. Before that, during the iPhone 11 era or even earlier, the TKIP encryption method was in normal use. However, the new iPhone models were incompatible with it, which obviously caused great inconvenience. I hope the engineers can fix this issue to support Wi-Fi with older encryption protocols.
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579
Dec ’25
NWConnection cancel: Do we need to wait for pending receive callbacks to be cancelled?
Hi, I’m using Network Framework to implement a UDP client via NWConnection, and I’m looking for clarification about the correct and fully safe shutdown procedure, especially regarding resource release. I have initiated some pending receive calls on the NWConnection (using receive). After calling connection.cancel(), do we need to wait for the cancellation of these pending receives? As mentioned in this thread, NWConnection retains references to the receive closures and releases them once they are called. If a receive closure holds a reference to the NWConnection itself, do we need to wait for these closures to be called to avoid memory leaks? Or, if there are no such retained references, we don't need to wait for the cancellation of the pending I/O and cancelled state for NWConnection?
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200
Dec ’25
Setup SearchDomains with NETransparentProxyProvider
We have a macOS system extension with NETransparentProxyProvider which is able to intercept traffic and handle it. We also wanted to setup few search domains from our network extension. However, unlike PacketTunnelProvider, NEDNSSettings are completely ignored with NETransparentProxyProvider. So whats the best way to setup few DNS search domains when using NETransparentProxyProvider.
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170
1w
Network extension doesn't get the updated preferred language after changing phone language
We’ve noticed an issue where after running a network extension, if the phone’s language is changed the Locale.preferredLanguages array is not updated and still returns the old array. It only returns the updated array when the app is reinstalled or the phone is restarted. This is unlike the app itself where using the same Locale.preferredLanguages API immediately returns the updated array. We think this issue is also the cause of notifications that are sent by the network extension being in the previous language as long as the app isn’t reinstalled or the phone is restarted, despite our Localizable file having localised strings for the new language. Feedback ID: FB20086051 The feedback report includes a sample project with steps on how to reproduce the issue.
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1
211
Sep ’25
XPC listener initialized in System Extesnion invalidates incoming connection under certain conditions
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.
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Activity
Apr ’25
SSL certificate failure
This problem doesn’t appear to relate to the app as everything worked when using http (although an https setup issue may still be the problem). The problem appears to relate to the SSL server certificate on the Ubuntu server and the fact that apple does not accept that it is secure. However I have no problem with the equivalent Android app or web browser connections to the same rest API web services. There are numerous posts on these problems on Apple and other Forums, but none have helped me successfully address the issue. I ran an SSL server test on https://www.ssllabs.com/ssltest/ which gives ratings for SSL sites. The test gave an A rating although a number of minor issues were shown that may be crucial to the iOS failure. Some Sectigo certificates said self signed, which I couldn't understand. Error message from XCode log attached 2025-09-10 10:28:01.725091+0100 locateandclock[2291:1585213] ATS failed system trust 2025-09-10 10:28:01.725192+0100 locateandclock[2291:1585213] Connection 1: system TLS Trust evaluation failed(-9802) 2025-09-10 10:28:01.725291+0100 locateandclock[2291:1585213] Connection 1: TLS Trust encountered error 3:-9802 2025-09-10 10:28:01.725352+0100 locateandclock[2291:1585213] Connection 1: encountered error(3:-9802) 2025-09-10 10:28:01.726727+0100 locateandclock[2291:1585213] Task <4E41098F-6B71-4FB8-8753-78DD32961812>.<1> HTTP load failed, 0/0 bytes (error code: -1200 [3:-9802]) 2025-09-10 10:28:01.736504+0100 locateandclock[2291:1585213] Task <4E41098F-6B71-4FB8-8753-78DD32961812>.<1> finished with error [-1200] Error Domain=NSURLErrorDomain Code=-1200 "An SSL error has occurred and a secure connection to the server cannot be made." UserInfo={NSLocalizedRecoverySuggestion=Would you like to connect to the server anyway?, _kCFStreamErrorDomainKey=3, NSErrorPeerCertificateChainKey=( "<cert(0x10681be00) s: *.xxxxxxxxxxx.co.uk i: Sectigo Public Server Authentication CA DV R36>", "<cert(0x10681c800) s: Sectigo Public Server Authentication CA DV R36 i: Sectigo Public Server Authentication Root R46>", "<cert(0x10681d200) s: Sectigo Public Server Authentication Root R46 i: Sectigo Public Server Authentication Root R46>" ), NSErrorClientCertificateStateKey=0, NSErrorFailingURLKey=https://xxxxxxxxxxxx.co.uk/insertclocking, NSErrorFailingURLStringKey=https://xxxxxxxxxxxx.co.uk/insertclocking, NSUnderlyingError=0x282361650 {Error Domain=kCFErrorDomainCFNetwork Code=-1200 "(null)" UserInfo={_kCFStreamPropertySSLClientCertificateState=0, kCFStreamPropertySSLPeerTrust=<SecTrustRef: 0x281cf4460>, _kCFNetworkCFStreamSSLErrorOriginalValue=-9802, _kCFStreamErrorDomainKey=3, _kCFStreamErrorCodeKey=-9802, kCFStreamPropertySSLPeerCertificates=( "<cert(0x10681be00) s: *.xxxxxxxxxxxxxco.uk i: Sectigo Public Server Authentication CA DV R36>", "<cert(0x10681c800) s: Sectigo Public Server Authentication CA DV R36 i: Sectigo Public Server Authentication Root R46>", "<cert(0x10681d200) s: Sectigo Public Server Authentication Root R46 i: Sectigo Public Server Authentication Root R46>" )}}, _NSURLErrorRelatedURLSessionTaskErrorKey=( "LocalDataTask <4E41098F-6B71-4FB8-8753-78DD32961812>.<1>" ), _kCFStreamErrorCodeKey=-9802, _NSURLErrorFailingURLSessionTaskErrorKey=LocalDataTask <4E41098F-6B71-4FB8-8753-78DD32961812>.<1>, NSURLErrorFailingURLPeerTrustErrorKey=<SecTrustRef: 0x281cf4460>, NSLocalizedDescription=An SSL error has occurred and a secure connection to the server cannot be made.}
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301
Activity
Oct ’25
Remove wifi password
I have an app that connect to specific wifi but the macos always save password while i do not want user to remember the password. Anyway to stop or work around on it?
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155
Activity
Oct ’25
NetworkConnection throws EINVAL when receiving ping/pong control frames
Summary NetworkConnection<WebSocket> in iOS 26 Network framework throws POSIXErrorCode(rawValue: 22): Invalid argument when receiving WebSocket ping (opcode 9) or pong (opcode 10) control frames. This prevents proper WebSocket keep-alive functionality. Environment iOS 26.0 (Simulator) macOS 26.1 Xcode 26.0 Note: This issue was initially discovered on iOS 26 Simulator. The same behavior was confirmed on macOS 26, suggesting a shared bug in the Network framework. The attached sample code is for macOS for easier reproduction. Description When using the new NetworkConnection<WebSocket> API introduced in iOS 26 or macOS 26, the receive() method throws EINVAL error whenever a ping or pong control frame is received from the server. This is a critical issue because: WebSocket servers commonly send ping frames to keep connections alive Clients send ping frames to verify connection health The receive callback never receives the ping/pong frame - the error occurs before the frame reaches user code Steps to Reproduce Create a WebSocket connection to any server that supports ping/pong (e.g., wss://echo.websocket.org): import Foundation import Network // MARK: - WebSocket Ping/Pong EINVAL Bug Reproduction // This sample demonstrates that NetworkConnection<WebSocket> throws EINVAL // when receiving ping or pong control frames. @main struct WebSocketPingPongBug { static func main() async { print("=== WebSocket Ping/Pong EINVAL Bug Reproduction ===\n") do { try await testPingPong() } catch { print("Test failed with error: \(error)") } } static func testPingPong() async throws { let host = "echo.websocket.org" let port: UInt16 = 443 print("Connecting to wss://\(host)...") let endpoint = NWEndpoint.hostPort( host: NWEndpoint.Host(host), port: NWEndpoint.Port(rawValue: port)! ) try await withNetworkConnection(to: endpoint, using: { WebSocket { TLS { TCP() } } }) { connection in print("Connected!\n") // Start receive loop in background let receiveTask = Task { var messageCount = 0 while !Task.isCancelled { do { let (data, metadata) = try await connection.receive() messageCount += 1 print("[\(messageCount)] Received frame - opcode: \(metadata.opcode)") if let text = String(data: data, encoding: .utf8) { print("[\(messageCount)] Content: \(text)") } else { print("[\(messageCount)] Binary data: \(data.count) bytes") } } catch let error as NWError { if case .posix(let code) = error, code == .EINVAL { print("❌ EINVAL error occurred! (POSIXErrorCode 22: Invalid argument)") print(" This is the bug - ping/pong frame caused EINVAL") // Continue to demonstrate workaround continue } print("Receive error: \(error)") break } catch { print("Receive error: \(error)") break } } } // Wait for initial message from server try await Task.sleep(for: .seconds(2)) // Test 1: Send text message (should work) print("\n--- Test 1: Sending text message ---") try await connection.send("Hello, WebSocket!") print("✅ Text message sent") try await Task.sleep(for: .seconds(1)) // Test 2: Send ping (pong response will cause EINVAL) print("\n--- Test 2: Sending ping frame ---") print("Expecting EINVAL when pong is received...") let pingMetadata = NWProtocolWebSocket.Metadata(opcode: .ping) try await connection.ping(Data()) { pingMetadata } print("✅ Ping sent, waiting for pong...") // Wait for pong response try await Task.sleep(for: .seconds(2)) // Cleanup receiveTask.cancel() print("\n=== Test Complete ===") print("If you saw 'EINVAL error occurred!' above, the bug is reproduced.") } } } The receive() call fails with error when pong arrives: ❌ EINVAL error occurred! (POSIXErrorCode 22: Invalid argument) Test Results Scenario Result Send/receive text (opcode 1) ✅ OK Client sends ping, receives pong ❌ EINVAL on pong receive Expected Behavior The receive() method should successfully return ping and pong frames, or at minimum, handle them internally without throwing an error. The autoReplyPing option should allow automatic pong responses without disrupting the receive loop. Actual Behavior When a ping or pong control frame is received: The receive() method throws NWError.posix(.EINVAL) The frame never reaches user code (no opcode check is possible) The connection remains valid, but the receive loop is interrupted Workaround Catch the EINVAL error and restart the receive loop: while !Task.isCancelled { do { let received = try await connection.receive() // Process message } catch let error as NWError { if case .posix(let code) = error, code == .EINVAL { // Control frame caused EINVAL, continue receiving continue } throw error } } This workaround allows continued operation but: Cannot distinguish between ping-related EINVAL and other EINVAL errors Cannot access the ping/pong frame content Cannot implement custom ping/pong handling Impact WebSocket connections to servers that send periodic pings will experience repeated EINVAL errors Applications must implement workarounds that may mask other legitimate errors Additional Information Packet capture confirms ping/pong frames are correctly transmitted at the network level The error occurs in the Network framework's internal processing, before reaching user code
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Activity
Dec ’25
Network Extension – Delayed Startup Time
I've implemented a custom VPN system extension for macOS, utilizing Packet Tunnel Provider. One of the users reported a problem: he was connected to the VPN, and then his Mac entered sleep mode. Upon waking, the VPN is supposed to connect automatically (because of the on-demand rules). The VPN's status changed to 'connecting', but it remained stuck in this status. From my extension logs, I can see that the 'startTunnelWithOption()' function was called 2 minutes after the user clicked the 'connect' button. From the system logs, I noticed some 'suspicious' logs, but I can't be sure if they are related to the problem. Some of them are: kernel: (Sandbox) Sandbox: nesessionmanager(562) deny(1) system-fsctl (_IO "h" 47) entitlement com.apple.developer.endpoint-security.client not present or not true (I don't need this entitlement at the extension) nesessionmanager: [com.apple.networkextension:] NESMVPNSession[Primary Tunnel:XXXXXX(null)]: Skip a start command from YYYYY:session in state connecting NetworkExtension.com.***: RunningBoard doesn't recognize submitted process - treating as a anonymous process sysextd: activateDecision found existing entry of same version: state activated_enabled, ID FAE... Are any of the logs related to the above problem? How can I debug such issues? What info should I get from the user?
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299
Activity
Oct ’25
DNS filter stops responding after a minute
We have developed a DNS filter based on NEDNSProxyProvider. It works great for a minute, then it stops responding. Our logs indicate that during the outage our extension gets DNS requests and formulates DNS responses that it hands back to the OS, but from outside of our code it is as though our extension is not responding.
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118
Activity
Mar ’25
WebAuthenticationSession under a carrier-provided satellite network?
(related post: How to optimize my app for for a carrier-provided satellite network? ) I am trying to implement an app so that it works under a carrier-provided satellite network. The app uses (AS)WebAuthenticationSession for signing in. If the app is entitled to access a satellite network, will (AS)WebAuthenticationSession work as well? How about WKWebView and SFSafariViewController? Is there a way to test(simulate) a ultra-constrained network on a device or a simulator to see the expected behavior? Thanks,
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450
Activity
Jul ’25
DNS Resolution fails in 15.4
Hi, DNS resolution using libresolv (res_nquery) fails in 15.4 when connected to VPN. The same is working fine for 15.3 and lower and this happens for all the domains. The method returns -1 and res->res_h_errno is set to 2. In wireshark we can see that the DNS request is sent and server also returns the response successfully. The same works fine if we use TCP instead of UDP by setting the following option res->options |= RES_USEVC;
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225
Activity
Apr ’25
XPC connection consistently invalidated on app upgrade
Hi, Our project is a MacOS SwiftUI GUI application that bundles a System Network Extension, signed with a Developer ID certificate for distribution outside of the app store. The system network extension is used to write a packet tunnel provider. The signing of the app & network extension is handled by XCode (v16.0.0), we do not run codesign ourselves. We have no issues with XPC or the system network extension during normal usage, nor when the application is installed on a user's device for the first time. The problem only arises when the user upgrades the application. I have experienced this issue myself, as have our users. It's been reported on Apple Silicon macbooks running at least macOS 15.3.2. Much like the SimpleFirewall example (which we used as a reference), we use XPC for basic communication of state between the app and NE. These XPC connections stop working when the user installs a new version of the app, with OS logs from the process indicating that the connection is immediately invalidated. Subsequent connection attempts are also immediately invalidated. Toggling the VPN in system settings (or via the app) does not resolve the problem, nor does restarting the app, nor does deleting and reinstalling the app, nor does restarting the device. The only reliable workaround is to delete the system extension in Login Items & Extensions, under Network Extensions. No device restart is necessary to garbage collect the old extension - once the extension is reapproved by the user, the XPC issue resolves itself. This would be an acceptable workaround were it possible to automate the deleting of the system extension, but that appears deliberately not possible, and requiring our users to do this each time they update is unreasonable. When the upgraded app is opened for the first time, the OSSystemExtensionRequest request is sent, and the outcome is that the previously installed system network extension is replaced, as both the CFBundleVersion and CFBundleShortVersionString differ. When this issue is encountered, the output of systemextensionsctl list shows the later version is installed and activated. I've been able to reproduce this bug on my personal laptop, with SIP on and systemextensionsctl developer off, but on my work laptop with SIP off and systemextensionsctl developer on (where the network extension is replaced on each activation request, instead of only when the version strings differ), I do not encounter this issue, which leads me to believe it has something to do with the notarization process. We notarize the pkg using xcrun notarytool, and then staple to the pkg. This is actually the same issue described in: https://developer.apple.com/forums/thread/711713 https://developer.apple.com/forums/thread/667597 https://developer.apple.com/forums/thread/742992 https://developer.apple.com/forums/thread/728063 but it's been a while since any of these threads were updated, and we've made attempts to address it off the suggestions in the threads to no avail. Those suggestions are: Switching to a .pkg installer from a .dmg As part of the .pkg preinstall, doing all of the following: Stopping the VPN (scutil --nc stop), shutting down the app (using osascript 'quit app id'), and deleting the app (which claims to delete the network extension, but not the approval in Login Items & Extensions remains??), by running rm -rf on the bundle in /Applications As part of the .pkg postinstall: Forcing macOS to ingest the App bundle's notarization ticket using spctl --assess. Ensuring NSXPCListener.resume() is called after autoreleasepool { NEProvider.startSystemExtensionMode() } (mentioned in a forum thread above as a fix, did not help.) One thing I'm particularly interested in is the outcome of this feedback assistant ticket, as I can't view it: FB11086599. It was shared on this forum in the first thread above, and supposedly describes the same issue. I almost find it hard to believe that this issue has been around for this many years without a workaround (there's system network extension apps out there that appear to work fine when updating, are they not using XPC?), so I wonder if there's a fix described in that FB ticket. Since I can't view that above feedback ticket, I've created my own: FB17032197
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421
Activity
Jun ’25
Need Inputs on Which Extension to Use
Hi all, I have a working macOS (Intel) system extension app that currently uses only a Content Filter (NEFilterDataProvider). I need to capture/log HTTP and HTTPS traffic in plain text, and I understand NETransparentProxyProvider is the right extension type for that. For HTTPS I will need TLS inspection / a MITM proxy — I’m new to that and unsure how complex it will be. For DNS data (in plain text), can I use the same extension, or do I need a separate extension type such as NEPacketTunnelProvider, NEFilterPacketProvider, or NEDNSProxyProvider? Current architecture: Two Xcode targets: MainApp and a SystemExtension target. The SystemExtension target contains multiple network extension types. MainApp ↔ SystemExtension communicate via a bidirectional NSXPC connection. I can already enable two extensions (Content Filter and TransparentProxy). With the NETransparentProxy, I still need to implement HTTPS capture. Questions I’d appreciate help with: Can NETransparentProxy capture the DNS fields I need (dns_hostname, dns_query_type, dns_response_code, dns_answer_number, etc.), or do I need an additional extension type to capture DNS in plain text? If a separate extension is required, is it possible or problematic to include that extension type (Packet Tunnel / DNS Proxy / etc.) in the same SystemExtension Xcode target as the TransparentProxy? Any recommended resources or guidance on TLS inspection / MITM proxy setup for capturing HTTPS logs? There are multiple DNS transport types — am I correct that capturing DNS over UDP (port 53) is not necessarily sufficient? Which DNS types should I plan to handle? I’ve read that TransparentProxy and other extension types (e.g., Packet Tunnel) cannot coexist in the same Xcode target. Is that true? Best approach for delivering logs from multiple extensions to the main app (is it feasible)? Or what’s the best way to capture logs so an external/independent process (or C/C++ daemon) can consume them? Required data to capture (not limited to): All HTTP/HTTPS (request, body, URL, response, etc.) DNS fields: dns_hostname, dns_query_type, dns_response_code, dns_answer_number, and other DNS data — all in plain text. I’ve read various resources but remain unclear which extension(s) to use and whether multiple extension types can be combined in one Xcode target. Please ask if you need more details. Thank you.
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304
Activity
Jan ’26
Network Push Provider Wifi Selection Behavior
In our App, we have a network extension with a NEAppPushProvider subclass running. We run the following steps Setup a dual-band wireless router per the following: Broadcasting 2.4 GHz and 5 GHz channels Same SSID names for both channels Connected to the production network to the router DHCP assigning addresses in the 10.1.x.x network Connect the mobile device to the 5 GHz network (if needed, turn off the 2.4 GHz network temporarily; once the device connects to the 5 GHz network, the 2.4 GHz network can be turned back on). Create a NEAppPushManager in the App, using the SSID from the above mentioned network and set it to the matchSSIDs property. Call saveToPreferences() on the push manager to save. A. We have UI that shows the extension has been started and it has connected to the server successfully. Walk out of the range of the 5 GHz channel of the router, but stay within range of the 2.4ghz channel. Wait for the mobile device to connect to the 2.4 GHz channel. Expected: The extension would reconnect to the 2.4ghz network. Observed: The extension does not reconnect. Checking the logs for the extension we see that the following was called in the push provider subclass. stop(with:completionHandler:) > PID: 808 | 🗒️🛑 Stopped with reason 3: "noNetworkAvailable" The expectation is that start() on the NEAppPushProvider subclass would be called. Is this an incorrect expectation? How does the NEAppPushProvider handle same network SSID roaming among various band frequencies? I looked at the documentation and did not find any settings targeting 2.4 or 5 ghz networks. Please advise on what to do.
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144
Activity
Apr ’25
Running headless app as root for handling VPN and launching microservices
Hello to all I have coded in swift a headless app, that launches 3 go microservices and itself. The app listens via unix domain sockets for commands from the microservices and executes different VPN related operations, using the NEVPNManager extension. Because there are certificates and VPN operations, the headless app and two Go microservices must run as root. The app and microservices run perfectly when I run in Xcode launching the swift app as root. However, I have been trying for some weeks already to modify the application so at startup it requests the password and runs as root or something similar, so all forked apps also run as root. I have not succeeded. I have tried many things, the last one was using SMApp but as the swift app is a headless app and not a CLI command app it can not be embedded. And CLI apps can not get the VPN entitlements. Can anybody please give me some pointers how can I launch the app so it requests the password and runs as root in background or what is the ideal framework here? thank you again.
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384
Activity
Dec ’25
How to restore macOS routing table after VPN crash or routing changes?
Hi, I have a VPN product for macOS. When activated, it creates a virtual interface that capture all outgoing traffic for the VPN. the VPN encrypt it, and send it to the tunnel gateway. The gateway then decapsulates the packet and forwards it to the original destination. To achieve this, The vpn modifies the routing table with the following commands: # after packets were encoded with the vpn protocol, re-send them through # the physical interface /sbin/route add -host <tunnel_gateway_address_in_physical_subnet> <default_gateway> -ifp en0 > /dev/null 2>&1 # remove the default rule for en0 and replace it with scoped rule /sbin/route delete default <default_gateway> -ifp en0 > /dev/null 2>&1 /sbin/route add default <default_gateway> -ifscope en0 > /dev/null 2>&1 # create new rule for the virtual interface that will catch all packets # for the vpn /sbin/route add default <tunnel_gateway_address_in_tunnel_subnet> -ifp utunX > /dev/null 2>&1 This works in most cases. However, there are scenarios where the VPN process may crash, stop responding, or another VPN product may alter the routing table. When that happens, packets may no longer go out through the correct interface. Question: Is there a way to reliably reconstruct the routing table from scratch in such scenarios? Ideally, I would like to rebuild the baseline rules for the physical interface (e.g., en0) and then reapply the VPN-specific rules on top. Are there APIs, system utilities, or best practices in macOS for restoring the original routing configuration before reapplying custom VPN routes? Thanks
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439
Activity
Sep ’25
Change includeAllNetworks from NetworkExtension while tunnel is running
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
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1k
Activity
Mar ’25
Can NWConnection.receive(minimumIncompleteLength:maximumLength:) return nil data for UDP while connection remains .ready?
I’m using Network Framework with UDP and calling: connection.receive(minimumIncompleteLength: 1, maximumLength: 1500) { data, context, isComplete, error in ... // Some Logic } Is it possible for this completion handler to be called with data==nil if I haven't received any kind of error, i.e., error==nil and the connection is still in the .ready state?
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152
Activity
3w
Network System Extension cannot use network interface of another VPN
Hi, Our project is a MacOS SwiftUI GUI application that bundles a (Sandboxed) System Network Extension, signed with a Developer ID certificate for distribution outside of the app store. The system network extension is used to write a packet tunnel provider (NEPacketTunnelProvider), as our project requires the creation of a TUN device. In order for our System VPN to function, it must reach out to a (self-hosted) server (i.e. to discover a list of peers). Being self-hosted, this server is typically not accessible via the public web, and may only be accessible from within a VPN (such as those also implemented using NEPacketTunnelProvider, e.g. Tailscale, Cloudflare WARP). What we've discovered is that the networking code of the System Network Extension process does not attempt to use the other VPN network interfaces (utunX) on the system. In practice, this means requests to IPs and hostnames that should be routed to those interfaces time out. Identical requests made outside of the Network System Extension process use those interfaces and succeed. The simplest example is where we create a URLSession.downloadTask for a resource on the server. A more complicated example is where we execute a Go .dylib that continues to communicate with that server. Both types of requests time out. Two noteworthy logs appear when packets fail to send, both from the kernel 'process': cfil_hash_entry_log:6088 <CFIL: Error: sosend_reinject() failed>: [30685 com.coder.Coder-Desktop.VPN] <UDP(17) out so b795d11aca7c26bf 57728068503033955 57728068503033955 age 0> lport 3001 fport 3001 laddr 100.108.7.40 faddr 100.112.177.88 hash 58B15863 cfil_service_inject_queue:4472 CFIL: sosend() failed 49 I also wrote some test code that probes using a UDP NWConnection and NWPath availableInterfaces. When run from the GUI App, multiple interfaces are returned, including the one that routes the address, utun5. When ran from within the sysex, only en0 is returned. I understand routing a VPN through another is unconventional, but we unfortunately do need this functionality one way or another. Is there any way to modify which interfaces are exposed to the sysex? Additionally, are these limitations of networking within a Network System Extension documented anywhere? Do you have any ideas why this specific limitation might exist?
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411
Activity
Jul ’25
iPhone 17(iOS26) Unable to join the Wi-Fi(TKIP)
Device: iPhone 17 Series System: iOS 26.0.0 Wi-Fi: TKIP encryption protocol Question: Unable to join the network We have several products that are used by connecting to iPhone via Wi-Fi. Recently, many customers who have purchased the iPhone 17 series have reported that they are unable to connect to Wi-Fi. For Wi-Fi with TKIP encryption, after entering the password correctly to connect to the Wi-Fi, a pop-up appears stating "Unable to join the network.". Only Wi-Fi with WPA2-AES can be used normally. Before that, during the iPhone 11 era or even earlier, the TKIP encryption method was in normal use. However, the new iPhone models were incompatible with it, which obviously caused great inconvenience. I hope the engineers can fix this issue to support Wi-Fi with older encryption protocols.
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579
Activity
Dec ’25
NWConnection cancel: Do we need to wait for pending receive callbacks to be cancelled?
Hi, I’m using Network Framework to implement a UDP client via NWConnection, and I’m looking for clarification about the correct and fully safe shutdown procedure, especially regarding resource release. I have initiated some pending receive calls on the NWConnection (using receive). After calling connection.cancel(), do we need to wait for the cancellation of these pending receives? As mentioned in this thread, NWConnection retains references to the receive closures and releases them once they are called. If a receive closure holds a reference to the NWConnection itself, do we need to wait for these closures to be called to avoid memory leaks? Or, if there are no such retained references, we don't need to wait for the cancellation of the pending I/O and cancelled state for NWConnection?
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Activity
Dec ’25
Setup SearchDomains with NETransparentProxyProvider
We have a macOS system extension with NETransparentProxyProvider which is able to intercept traffic and handle it. We also wanted to setup few search domains from our network extension. However, unlike PacketTunnelProvider, NEDNSSettings are completely ignored with NETransparentProxyProvider. So whats the best way to setup few DNS search domains when using NETransparentProxyProvider.
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170
Activity
1w
Network extension doesn't get the updated preferred language after changing phone language
We’ve noticed an issue where after running a network extension, if the phone’s language is changed the Locale.preferredLanguages array is not updated and still returns the old array. It only returns the updated array when the app is reinstalled or the phone is restarted. This is unlike the app itself where using the same Locale.preferredLanguages API immediately returns the updated array. We think this issue is also the cause of notifications that are sent by the network extension being in the previous language as long as the app isn’t reinstalled or the phone is restarted, despite our Localizable file having localised strings for the new language. Feedback ID: FB20086051 The feedback report includes a sample project with steps on how to reproduce the issue.
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211
Activity
Sep ’25