Network Extension

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Customize and extend the core networking features of iOS, iPad OS, and macOS using Network Extension.

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TLS communication error between iPhone and iPad
We are implementing a connection between iPad and iPhone devices using LocalPushConnectivity, and have introduced SimplePushProvider into the project. We will have it switch between roles of Server and Client within a single project. ※ iPad will be Server and the iPhone will be Client. Communication between Server and Client is via TLS, with Server reading p12 file and Client setting public key. Currently, a TLS error code of "-9836" (invalid protocol version) is occurring when communicating from Client's SimplePushProvider to Server. I believe that Client is sending TLS1.3, and Server is set to accept TLS1.2 to 1.3. Therefore, I believe that the actual error is not due to TLS protocol version, but is an error that is related to security policy or TLS communication setting. Example: P12 file does not meet some requirement NWProtocolTLS.Options setting is insufficient etc... I'm not sure what the problem is, so please help. For reference, I will attach you implementation of TLS communication settings. P12 file is self-signed and was created by exporting it from Keychain Access. Test environment: iPad (OS: 16.6) iPhone (OS: 18.3.2) ConnectionOptions: TLS communication settings public enum ConnectionOptions { public enum TCP { public static var options: NWProtocolTCP.Options { let options = NWProtocolTCP.Options() options.noDelay = true options.enableFastOpen return options } } public enum TLS { public enum Error: Swift.Error { case invalidP12 case unableToExtractIdentity case unknown } public class Server { public let p12: URL public let passphrase: String public init(p12 url: URL, passphrase: String) { self.p12 = url self.passphrase = passphrase } public var options: NWProtocolTLS.Options? { guard let data = try? Data(contentsOf: p12) else { return nil } let pkcs12Options = [kSecImportExportPassphrase: passphrase] var importItems: CFArray? let status = SecPKCS12Import(data as CFData, pkcs12Options as CFDictionary, &importItems) guard status == errSecSuccess, let items = importItems as? [[String: Any]], let importItemIdentity = items.first?[kSecImportItemIdentity as String], let identity = sec_identity_create(importItemIdentity as! SecIdentity) else { return nil } let options = NWProtocolTLS.Options() sec_protocol_options_set_min_tls_protocol_version(options.securityProtocolOptions, .TLSv12) sec_protocol_options_set_max_tls_protocol_version(options.securityProtocolOptions, .TLSv13) sec_protocol_options_set_local_identity(options.securityProtocolOptions, identity) sec_protocol_options_append_tls_ciphersuite(options.securityProtocolOptions, tls_ciphersuite_t.RSA_WITH_AES_128_GCM_SHA256) return options } } public class Client { public let publicKeyHash: String private let dispatchQueue = DispatchQueue(label: "ConnectionParameters.TLS.Client.dispatchQueue") public init(publicKeyHash: String) { self.publicKeyHash = publicKeyHash } // Attempt to verify the pinned certificate. public var options: NWProtocolTLS.Options { let options = NWProtocolTLS.Options() sec_protocol_options_set_min_tls_protocol_version(options.securityProtocolOptions, .TLSv12) sec_protocol_options_set_max_tls_protocol_version(options.securityProtocolOptions, .TLSv13) sec_protocol_options_set_verify_block( options.securityProtocolOptions, verifyClosure, dispatchQueue ) return options } private func verifyClosure( secProtocolMetadata: sec_protocol_metadata_t, secTrust: sec_trust_t, secProtocolVerifyComplete: @escaping sec_protocol_verify_complete_t ) { let trust = sec_trust_copy_ref(secTrust).takeRetainedValue() guard let serverPublicKeyData = publicKey(from: trust) else { secProtocolVerifyComplete(false) return } let keyHash = cryptoKitSHA256(data: serverPublicKeyData) guard keyHash == publicKeyHash else { // Presented certificate doesn't match. secProtocolVerifyComplete(false) return } // Presented certificate matches the pinned cert. secProtocolVerifyComplete(true) } private func cryptoKitSHA256(data: Data) -> String { let rsa2048Asn1Header: [UInt8] = [ 0x30, 0x82, 0x01, 0x22, 0x30, 0x0d, 0x06, 0x09, 0x2a, 0x86, 0x48, 0x86, 0xf7, 0x0d, 0x01, 0x01, 0x01, 0x05, 0x00, 0x03, 0x82, 0x01, 0x0f, 0x00 ] let data = Data(rsa2048Asn1Header) + data let hash = SHA256.hash(data: data) return Data(hash).base64EncodedString() } private func publicKey(from trust: SecTrust) -> Data? { guard let certificateChain = SecTrustCopyCertificateChain(trust) as? [SecCertificate], let serverCertificate = certificateChain.first else { return nil } let publicKey = SecCertificateCopyKey(serverCertificate) return SecKeyCopyExternalRepresentation(publicKey!, nil)! as Data } } } }
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265
May ’25
0xBAADCA11 Occurs when VoIP Call Incoming (APNs Push Notification)
I am developing a VoIP phone application(Our Phoneapp) using APNs VoIP push. I have a question regarding a behavior I discovered during testing of this application. When performing the following operations using an iPhoneSE3 with an sXGP-NW SIM inserted, 0xBAADCA11 occurs upon receiving an APNs VoIP PUSH. Do you have any information regarding this issue? 0xBAADCA11 occurs in operation 8. However, since there were no problems in operation 4 (the app works when Wi-Fi is off), I think there is no issue with the Our Phoneapp. [Configuration of system components] [VoIP Telephone] --Call to iPhone(Phoneapp)--> [Our VoIP PBX Server] -- VoIP PUSH request --> [Apple APNs Server] -- VoIP PUSH --> [Our Phoneapp (iPhoneSE3(with sXGP SIM)] [Operations] (The issue is reproducible 100% by following oparation) iPhoneSE3: Power on (iPhoneSE3 with sXGP SIM) iPhoneSE3: Wi-Fi off, connect to the internet via SIM. VoIP Telephone: Call to Our Phoneapp iPhoneSE3: Receives VoIP PUSH and Phoneapp launches. Successfully answers the call and communication is possible. (Receives VoIP push notification from APNs via sXGP SIM) iPhoneSE3: Wi-Fi is turned ON, connect to the internet via Wi-Fi. iPhoneSE3: Task kill Our Phoneapp. VoIP Telephone: Call to Our Phoneapp iPhoneSE3: iOS does not call the push notification delegate (didReceiveIncomingPushWithPayload). As a result our Phoneapp is unable to detect the incoming call, However, an ips log with 0xBAADCA11 is output. in other words, iOS received the VoIP PUSH, but Our Phoneapp dose not call CallKit, so Our Phoneapp was terminated by iOS.
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491
May ’25
Replacing Packet Filter (pf) with Content Filter for VPN Firewall Use Case
Hi, We're in the process of following Apple’s guidance on transitioning away from Packet Filter (pf) and migrating to a Network Extension-based solution that functions as a firewall. During this transition, we've encountered several limitations with the current Content Filter API and wanted to share our findings. Our VPN client relies on firewall functionality to enforce strict adherence to split tunneling rules defined via the routing table. This ensures that no traffic leaks outside the VPN tunnel, which is critical for our users for a variety of reasons. To enforce this, our product currently uses interface-scoped rules to block all non-VPN traffic outside the tunnel. Replicating this behavior with the Content Filter API (NEFilterDataProvider) appears to be infeasible today. The key limitation we've encountered is that the current Content Filter API does not expose information about the network interface associated with a flow. As a workaround, we considered using the flow’s local endpoint IP to infer the interface, but this data is not available until after returning a verdict to peek into the flow’s data—at which point the connection has already been established. This can result in connection metadata leaking outside the tunnel, which may contain sensitive information depending on the connection. What is the recommended approach for this use case? NEFilterPacketProvider? This may work, but it has a negative impact on network performance. Using a Packet Tunnel Provider and purely relying on enforceRoutes? Would this indeed ensure that no traffic can leak by targeting a specific interface or by using a second VPN extension? And more broadly—especially if no such approach is currently feasible with the existing APIs—we're interpreting TN3165 as a signal that pf should be considered deprecated and may not be available in the next major macOS release. Is that a reasonable interpretation?
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268
May ’25
NWConnections in Network Extension Redirected to Proxy
We have a setup where the system uses proxy settings configured via a PAC file. We are investigating how NWConnection behaves inside a Network Extension (NETransparentProxyProvider) with a transparent proxy configuration based on this PAC file. Scenario: The browser makes a connection which the PAC file resolves as "DIRECT" (bypassing the proxy) Our Network Extension intercepts this traffic for analysis The extension creates a new connection using NWConnection to the original remote address. The issue: despite the PAC file’s "DIRECT" decision, NWConnection still respects the system proxy settings and routes the connection through the proxy. Our questions: Is it correct that NWConnection always uses the system proxy if configured ? Does setting preferNoProxies = true guarantee bypassing the system proxy? Additionally: Whitelisting IPs in the Network Extension to avoid interception is not a viable solution because IPs may correspond to multiple services, and the extension only sees IP addresses, not domains (e.g., we want to skip scanning meet.google.com traffic but still scan other Google services on the same IP range). Are there any recommended approaches or best practices to ensure that connections initiated from a Network Extension can truly bypass the proxy (for example, for specific IP ranges or domains)?
1
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156
May ’25
Getting WIFI SSID
Greetings I'm trying to get on iPad the SSID from the wifi I'm connected to. For that, I added the wifi entitlement and I'm requesting permission to the user for Location. Once I have it, I'm using the function CNCopySupportedInterfaces to get the interfaces, but I can only receive the en0, which using the method CNCopyCurrentNetworkInfo returns nil. I also tried using the NEHotspotNetwork.fetchCurrent and the SSID keeps being nil. So right now I'm drawing a blank. Is there any way to make it work? Thanks.
1
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468
May ’25
Mac can't find or register NE App Extension without App Sandbox entitlement
Recently, while developing a network extension on macOS, I encountered a very interesting issue. When the App Sandbox entitlement is included, the NE (Network Extension) can be called and run normally. However, when the App Sandbox is removed, with everything else remaining unchanged, an error occurs. The logs are as follows: Failed to find an app extension with identifier app.acmeVpnM.extension and extension point com.apple.networkextension.packet-tunnel: (null) Found 0 registrations for app.acmeVpnM.extension (com.apple.networkextension.packet-tunnel) If you add app sandbox, it will run normally. this is my container app entitlement this is my NE extension (without App SandBox) I want to know the reason for this. App sandbox shouldn't be mandatory. How can I make my NE run in an environment without app sandbox?
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170
May ’25
Memory release problem of VPN connection object
Hello, I encountered a memory management issue while developing VPN functionality and would like to seek your advice. The specific phenomenon is as follows: Problem description: After multiple calls to the 'createTCPConnectToEndpoint' and 'create UDPSessionToEndpoint' interfaces to create connection objects, the application memory continues to grow. Even if the cancel interface is immediately called to actively release the object, the memory does not fall back. 3. Confirm that there is no other code referencing these objects, but the system does not seem to automatically reclaim memory. Attempted measures: Immediately call the cancel method after creating the object, and the memory is not reduced Use tools such as Profiler to monitor memory and confirm that objects have not been released. doubt: Is this phenomenon normal? Is there a known memory management mechanism (such as cache pooling) that causes delayed release? 2. Are there any other interfaces or methods (such as release, dispose) that need to be explicitly called? Supplementary Information: Development environment: [iOS 16, 14pm] Reproduction steps: After continuously creating connection objects, the memory grows without falling back. Could you please help confirm if there are any abnormalities and the correct memory release posture. Thank you for your support!
3
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118
May ’25
Packet Tunnel Provider with Per App VPN debugging
We have a vpn app which uses PacketTunnelProvider. We also support per-app vpn for iOS, I need help with debugging steps for an issue I am facing recently. In the per app vpn, we have split tunneling: some urls should be tunneled while others should be direct, for tunneled urls/ips everything is working as expected. But for "direct" resources, I am facing an issue where sometimes I don't get an ACK back from the browser. Leading to a series of retransmissions and eventually the direct website not loading. Some more points of data: we do get true for the writePackets call, which seems to mean that the vpn app did write the packets to the TUN interface, but we don't get an ACK from the browser. I want some way of debugging this further so I can check if the browser actually got the packets. I also suspect that there might be a loop with packets (we are reading the packets we just wrote onto TUN), but can't say for sure since the issue is intermittent, in case of a loop, I would expect it to always help. Any help would be greatly appreciated.
3
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194
May ’25
App occassionally crashing while connecting to public wifi
We are using the [NEHotspotHelper supportedNetworkInterfaces] to get the Wi-Fi interface in our app, but it occasionally crashes on some devices with the following stack trace: 0 CaptiveNetwork 0x0000000221d87a4c ServerConnectionGetHandlerQueue + 0 (ServerConnection.c:509) 1 CaptiveNetwork 0x0000000221d8577c CNPluginCopySupportedInterfaces + 180 (CNPlugin.c:457) 2 NetworkExtension 0x00000001b0446618 +[NEHotspotHelper supportedNetworkInterfaces] + 32 (NEHotspotHelper.m:563) It seems like the crash is happening on apple's api of supportedNetworkInterfaces. We would like to understand the cause of the crash.
2
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95
May ’25
NE System Extension stuck on Validation By Category
Hello, I'm having some problems when install my Packet Tunnel network extension as system extension on my mac(macos 15.0). It stuck on Validation By Category. (it works well as NE app extension on ios) systemextensionsctl list --- com.apple.system_extension.network_extension enabled active teamID bundleID (version) name [state] <...> com.myteam.balabalabla.ne (1.0/1) - [validating by category] This is my install System Extension Code sample public class SystemExtension: NSObject, OSSystemExtensionRequestDelegate { private let forceUpdate: Bool private let inBackground: Bool private let semaphore = DispatchSemaphore(value: 0) private var result: OSSystemExtensionRequest.Result? private var properties: [OSSystemExtensionProperties]? private var error: Error? private init(_ forceUpdate: Bool = false, _ inBackground: Bool = false) { } // some request function i overwrite public func activation() throws -> OSSystemExtensionRequest.Result? { let request = OSSystemExtensionRequest.activationRequest(forExtensionWithIdentifier: FilePath.packageName + ".myNeName", queue: .main) request.delegate = self OSSystemExtensionManager.shared.submitRequest(request) semaphore.wait() if let error { throw error } return result } public func getProperties() throws -> [OSSystemExtensionProperties] { let request = OSSystemExtensionRequest.propertiesRequest(forExtensionWithIdentifier: FilePath.packageName + ".myNeName", queue: .main) request.delegate = self OSSystemExtensionManager.shared.submitRequest(request) semaphore.wait() if let error { throw error } return properties! } public nonisolated static func install(forceUpdate: Bool = false, inBackground: Bool = false) async throws -> OSSystemExtensionRequest.Result? { try await Task.detached { try SystemExtension(forceUpdate, inBackground).activation() }.result.get() } public nonisolated static func uninstall() async throws -> OSSystemExtensionRequest.Result? { try await Task.detached { try SystemExtension().deactivation() }.result.get() } } // And other methods I follow this post Your Friend the System Log and use this command line to collect log. After I initiated the system extension request sudo log collect --last 5m Here is my log (),I only pasted some code snippets that caught me, full version see attachments.(only include com.apple.sysextd), if need more, plz ask me. 1. Some policy missing ```log 22:00:13.818257 `sysextd` extension mockTeamID app.balabala.com.mockbalabala (1.0/1) advancing state from staging to validating 22:00:13.818263 sysextd returning cdhash for local arch arm64 of extension app.balabala.com.mockbalabala info 2025-05-01 22:00:13.818336 sysextd Extension with identifier <private> reached state <private> 22:00:13.819185 sysextd [0x9a2034b00] activating connection: mach=false listener=false peer=false name=com.apple.CodeSigningHelper 22:00:13.819911 sysextd [0x9a2034b00] invalidated after the last release of the connection object 22:00:13.821024 sysextd making activation decision for extension with teamID teamID("mockTeamID ), identifier app.balabala.com.mockbalabala 22:00:13.821026 sysextd no related kext found for sysex `app.balabala.com.mockbalabala` 22:00:13.821027 sysextd no extension policy -- activation decision is UserOption nesessionmanager.system-extensions interrupted 22:00:14.313576 sysextd [0x9a2178280] invalidated because the client process (pid 1886) either cancelled the connection or exited 22:00:14.542154 sysextd connection to com.apple.nesessionmanager.system-extensions interrupted 22:00:14.542319 sysextd [0x9a2178000] Re-initialization successful; calling out to event handler with XPC_ERROR_CONNECTION_INTERRUPTED 22:00:14.542351 sysextd connection to com.apple.nesessionmanager.system-extensions interrupted 22:00:14.589375 nesessionmanager [0x6c80e4500] activating connection: mach=true listener=false peer=false name=com.apple.sysextd And when i debug the System Extension code i notice the request Error catch by didFailWithError public func request(_: OSSystemExtensionRequest, didFailWithError error: Error) { self.error = error semaphore.signal() } error is OSSystemExtensionErrorDomain code 1 This problem has been bothering me for a long time, I would appreciate any help, if need more info, comment, thank you.
3
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296
May ’25
Non-functioning IP_RECVIF on sockets proxied with NETransparentProxyProvider
Hi! I've noticed that the IP_RECVIF socket option, i.e.: int y = 1; setsockopt(fd, IPPROTO_IP, IP_RECVIF, &y, sizeof(y)); does not seem to work if the socket is proxied by a NETransparentProxyProvider type network extension: there's no ancillary data in messages received with recvmsg. As soon as I disable the network extension, recvmsg starts returning ancillary data containing the interface name. This seems to break some applications which rely on IP_RECVIF in the presence of a transparent proxy, making it, in fact, not transparent. One such example is Apple's own libresolv, which relies on IP_RECVIF and breaks if there's no ancillary data in the recvmsg result. I don't think that this is the intended behaviour, since IPV6_PKTINFO seems to work fine. I've filed a bug report (FB17586550) about this, however, I would greatly appreciate if someone could point me in the direction of a workaround.
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4
269
May ’25
wifi connect fail
Dear Apple: In our app, we will call the - (void) applyConfiguration:(NEHotspotConfiguration *) configuration completionHandler:(void (^)(NSError * error)) completionHandler; interface of NEHotspotConfigurationManager on Apple devices. However, we are encountering a problem where the connection to the 2.4G hotspot fails, and the error is nil when it fails. We checked the Wi-Fi air interface and found that the Apple phone does not send a probe request before connecting to the hotspot. However, we are unclear why the Apple device does not send the probe request frame. Could you please help us understand when the probe request frame is not sent during the hotspot connection and how to trigger it to send the probe request frame every time? Thank you.
4
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143
May ’25
BGAppRefreshTask Canceled Immediately by dasd in Network Extension
Dear Apple Support Team, My app, io.cylonix.sase, has a BGAppRefreshTask (io.cylonix.sase.ios.refresh) that is canceled by dasd ~9ms after submission from a Network Extension. Please help identify the cause and suggest a solution. App Details: App ID: io.cylonix.sase iOS Version: 17.1.1 (iPhone Xs Max) Network Extension: saseWgNetworkExtension with packet-tunnel-provider entitlement Use Case: VPN app; Network Extension records file receipts in shared group UserDefaults and schedules BGAppRefreshTask to wake the main app. App Usage: High (frequently used) System State: Sufficient resources (not low on battery or memory) Issue: The task is submitted but canceled immediately with priority 10. It has never run, so rate-limiting is not an issue. ` debug 22:09:37.952749-0700 dasd Best binding found for evaluator 0x16d541720: &lt;private&gt; debug 22:09:37.954483-0700 dasd Invoking selector backgroundTaskSchedulerPermittedIdentifiersWithContext:tableID:unitID:unitBytes: on &lt;LSApplicationRecord 0x724844650&gt; default 22:09:37.955563-0700 dasd CANCELED: bgRefresh-io.cylonix.sase.ios.refresh:ABDAFA at priority 10 &lt;private&gt;!
6
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204
May ’25
When adding a VPN configuration, the Settings app doesn't continue with the configuration process
Sometimes when adding a VPN configuration, it just redirects to the Settings app and doesn’t continue with the rest of the configuration process like prompting for passcode. But it proceeds as normal after the 2nd or 3rd try. This issue is occurring on iOS 18.5 build 22F5068a but it has been a problem over several versions now. Feedback ID: FB17458055
1
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154
May ’25
split Tunnel + exclude APNs
Hello, im currently developing proxy app with XrayCore trying to bypass APNs when tunnel us up and i found .excludeAPNs property in NETunnelProviderProtocol that works only when includeAllNetworks property is also TRUE. I wonder if there is a possible way to make APNs bypass tunnel in split tunnelling mode? because we use excludedRoutes and full tunnel is not an option
1
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115
May ’25
Packet Tunnel Provider with Per App VPN debugging
We have a VPN app built using PacketTunnelProvider and support per-app VPN on iOS. We're currently investigating an issue specific to per-app VPN configurations that use split tunneling, where some URLs are routed through the VPN tunnel while others are intended to go directly. Tunneled traffic works as expected. However, for direct traffic, we observe intermittent failures where the browser does not receive an ACK, leading to repeated retransmissions and eventual page load failures. This issue appears only in per-app VPN scenarios, and we've reproduced it across multiple MDM solutions (Intune, CEM) and multiple managed browsers. It's intermittent but frequently reproducible with common public URLs routed directly. Key observations: writePackets returns true, confirming the VPN app writes packets to the TUN interface. Despite that, the browser often fails to acknowledge receipt (no ACK), suggesting it may not receive the packet at all. We suspect a possible packet loop, where packets written to TUN are immediately read back by the app. However, due to the intermittent nature of the issue, this is hard to confirm. A consistent loop would likely result in persistent failures, not sporadic ones. We are attaching: A Wireshark summary - highlighting the missing ACK and retransmission pattern. As we cannot attach the xlsx file or a zip file, we have took the screenshots of the files names as image1, image2, image3, image4 and image5 in sequence. Dails on the iOS device and MDM environment. NETunnelProviderProtocol configuration that reproduces the issue Any guidance on how to further debug this, particularly on confirming packet delivery to the browser and identifying potential loops would be greatly appreciated. Thank you. e t
3
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120
May ’25
How to avoid my local server flows in Transparent App Proxy
I have written the Transparent App Proxy and can capture the network flow and send it to my local server. I want to avoid any processing on the traffic outgoing from my server and establish a connection with a remote server, but instead of connecting to the remote server, it again gets captured and sent back to my local server. I am not getting any clue on how to ignore these flows originating from my server. Any pointers, API, or mechanisms that will help me?
9
2
342
Apr ’25
Rules on AppPushProvider deinitialization
Here's what the documentation says https://developer.apple.com/documentation/networkextension/maintaining-a-reliable-network-connection Confirm that your NEAppPushProvider implementation doesn’t create a retain cycle with itself. After you call the completionHandler that the system passes to stop(with:completionHandler:), the Network Extension framework releases your NEAppPushProvider instance. This instance typically deallocates from memory when released, but if the instance has a retain cycle with itself, it fails to deallocate and wastes memory. Failure to deallocate can also cause the system to have two or more instances of your push provider, leading to inconsistent behavior. Use Instruments or add a logging statement to deinit to verify that your NEAppPushProvider deinitializes when expected. I observe that when I turn off the wifi, the AppPushProvider subclass fully deinitializes. But when I call removeFromPreferences on the NEAppPushManager from the app, it calls stop() on my AppPushProvider subclass, but it does not initialize. Should I be alarmed by this behavior? Will this cause a memory leak? Will this cause multiple Extension/AppPushProviders to be operating concurrently? For testing, I've removed everything except for logs and some singleton calls. No closures capturing self, and no strong references of self being passed anywhere. I am also not using the debugger, and am using the console to debug.
3
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122
Apr ’25
Flow Divert behavior
Hello, Our app uses Network Extension / Packet Tunnel Provider to establish VPN connections on macOS and iOS. We have observed that after creating a utun device and adding any IPv4 routes (NEPacketTunnelNetworkSettings.IPv4Settings), the OS automatically adds several host routes via utun to services such as Akamai, Apple Push, etc. These routes appear to correspond to TCP flows that were active at the moment the VPN connection was established. When a particular TCP flow ends, the corresponding host route is deleted. We understand this is likely intended to avoid breaking existing TCP connections. However, we find the behavior of migrating existing TCP flows to the new utun interface simply because any IPv4 route is added somewhat questionable. This approach would make sense in a "full-tunnel" scenario — for example, when all IPv4 traffic (e.g., 0.0.0.0/0) is routed through the tunnel — but not necessarily in a "split-tunnel" configuration where only specific IPv4 routes are added. Is there any way to control or influence this behavior? Would it be possible for FlowDivert to differentiate between full-tunnel and split-tunnel cases, and only preserve existing TCP flows via utun in the full-tunnel scenario? Thank you.
0
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115
Apr ’25
TLS communication error between iPhone and iPad
We are implementing a connection between iPad and iPhone devices using LocalPushConnectivity, and have introduced SimplePushProvider into the project. We will have it switch between roles of Server and Client within a single project. ※ iPad will be Server and the iPhone will be Client. Communication between Server and Client is via TLS, with Server reading p12 file and Client setting public key. Currently, a TLS error code of "-9836" (invalid protocol version) is occurring when communicating from Client's SimplePushProvider to Server. I believe that Client is sending TLS1.3, and Server is set to accept TLS1.2 to 1.3. Therefore, I believe that the actual error is not due to TLS protocol version, but is an error that is related to security policy or TLS communication setting. Example: P12 file does not meet some requirement NWProtocolTLS.Options setting is insufficient etc... I'm not sure what the problem is, so please help. For reference, I will attach you implementation of TLS communication settings. P12 file is self-signed and was created by exporting it from Keychain Access. Test environment: iPad (OS: 16.6) iPhone (OS: 18.3.2) ConnectionOptions: TLS communication settings public enum ConnectionOptions { public enum TCP { public static var options: NWProtocolTCP.Options { let options = NWProtocolTCP.Options() options.noDelay = true options.enableFastOpen return options } } public enum TLS { public enum Error: Swift.Error { case invalidP12 case unableToExtractIdentity case unknown } public class Server { public let p12: URL public let passphrase: String public init(p12 url: URL, passphrase: String) { self.p12 = url self.passphrase = passphrase } public var options: NWProtocolTLS.Options? { guard let data = try? Data(contentsOf: p12) else { return nil } let pkcs12Options = [kSecImportExportPassphrase: passphrase] var importItems: CFArray? let status = SecPKCS12Import(data as CFData, pkcs12Options as CFDictionary, &amp;importItems) guard status == errSecSuccess, let items = importItems as? [[String: Any]], let importItemIdentity = items.first?[kSecImportItemIdentity as String], let identity = sec_identity_create(importItemIdentity as! SecIdentity) else { return nil } let options = NWProtocolTLS.Options() sec_protocol_options_set_min_tls_protocol_version(options.securityProtocolOptions, .TLSv12) sec_protocol_options_set_max_tls_protocol_version(options.securityProtocolOptions, .TLSv13) sec_protocol_options_set_local_identity(options.securityProtocolOptions, identity) sec_protocol_options_append_tls_ciphersuite(options.securityProtocolOptions, tls_ciphersuite_t.RSA_WITH_AES_128_GCM_SHA256) return options } } public class Client { public let publicKeyHash: String private let dispatchQueue = DispatchQueue(label: "ConnectionParameters.TLS.Client.dispatchQueue") public init(publicKeyHash: String) { self.publicKeyHash = publicKeyHash } // Attempt to verify the pinned certificate. public var options: NWProtocolTLS.Options { let options = NWProtocolTLS.Options() sec_protocol_options_set_min_tls_protocol_version(options.securityProtocolOptions, .TLSv12) sec_protocol_options_set_max_tls_protocol_version(options.securityProtocolOptions, .TLSv13) sec_protocol_options_set_verify_block( options.securityProtocolOptions, verifyClosure, dispatchQueue ) return options } private func verifyClosure( secProtocolMetadata: sec_protocol_metadata_t, secTrust: sec_trust_t, secProtocolVerifyComplete: @escaping sec_protocol_verify_complete_t ) { let trust = sec_trust_copy_ref(secTrust).takeRetainedValue() guard let serverPublicKeyData = publicKey(from: trust) else { secProtocolVerifyComplete(false) return } let keyHash = cryptoKitSHA256(data: serverPublicKeyData) guard keyHash == publicKeyHash else { // Presented certificate doesn't match. secProtocolVerifyComplete(false) return } // Presented certificate matches the pinned cert. secProtocolVerifyComplete(true) } private func cryptoKitSHA256(data: Data) -&gt; String { let rsa2048Asn1Header: [UInt8] = [ 0x30, 0x82, 0x01, 0x22, 0x30, 0x0d, 0x06, 0x09, 0x2a, 0x86, 0x48, 0x86, 0xf7, 0x0d, 0x01, 0x01, 0x01, 0x05, 0x00, 0x03, 0x82, 0x01, 0x0f, 0x00 ] let data = Data(rsa2048Asn1Header) + data let hash = SHA256.hash(data: data) return Data(hash).base64EncodedString() } private func publicKey(from trust: SecTrust) -&gt; Data? { guard let certificateChain = SecTrustCopyCertificateChain(trust) as? [SecCertificate], let serverCertificate = certificateChain.first else { return nil } let publicKey = SecCertificateCopyKey(serverCertificate) return SecKeyCopyExternalRepresentation(publicKey!, nil)! as Data } } } }
Replies
3
Boosts
0
Views
265
Activity
May ’25
0xBAADCA11 Occurs when VoIP Call Incoming (APNs Push Notification)
I am developing a VoIP phone application(Our Phoneapp) using APNs VoIP push. I have a question regarding a behavior I discovered during testing of this application. When performing the following operations using an iPhoneSE3 with an sXGP-NW SIM inserted, 0xBAADCA11 occurs upon receiving an APNs VoIP PUSH. Do you have any information regarding this issue? 0xBAADCA11 occurs in operation 8. However, since there were no problems in operation 4 (the app works when Wi-Fi is off), I think there is no issue with the Our Phoneapp. [Configuration of system components] [VoIP Telephone] --Call to iPhone(Phoneapp)--> [Our VoIP PBX Server] -- VoIP PUSH request --> [Apple APNs Server] -- VoIP PUSH --> [Our Phoneapp (iPhoneSE3(with sXGP SIM)] [Operations] (The issue is reproducible 100% by following oparation) iPhoneSE3: Power on (iPhoneSE3 with sXGP SIM) iPhoneSE3: Wi-Fi off, connect to the internet via SIM. VoIP Telephone: Call to Our Phoneapp iPhoneSE3: Receives VoIP PUSH and Phoneapp launches. Successfully answers the call and communication is possible. (Receives VoIP push notification from APNs via sXGP SIM) iPhoneSE3: Wi-Fi is turned ON, connect to the internet via Wi-Fi. iPhoneSE3: Task kill Our Phoneapp. VoIP Telephone: Call to Our Phoneapp iPhoneSE3: iOS does not call the push notification delegate (didReceiveIncomingPushWithPayload). As a result our Phoneapp is unable to detect the incoming call, However, an ips log with 0xBAADCA11 is output. in other words, iOS received the VoIP PUSH, but Our Phoneapp dose not call CallKit, so Our Phoneapp was terminated by iOS.
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13
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491
Activity
May ’25
Replacing Packet Filter (pf) with Content Filter for VPN Firewall Use Case
Hi, We're in the process of following Apple’s guidance on transitioning away from Packet Filter (pf) and migrating to a Network Extension-based solution that functions as a firewall. During this transition, we've encountered several limitations with the current Content Filter API and wanted to share our findings. Our VPN client relies on firewall functionality to enforce strict adherence to split tunneling rules defined via the routing table. This ensures that no traffic leaks outside the VPN tunnel, which is critical for our users for a variety of reasons. To enforce this, our product currently uses interface-scoped rules to block all non-VPN traffic outside the tunnel. Replicating this behavior with the Content Filter API (NEFilterDataProvider) appears to be infeasible today. The key limitation we've encountered is that the current Content Filter API does not expose information about the network interface associated with a flow. As a workaround, we considered using the flow’s local endpoint IP to infer the interface, but this data is not available until after returning a verdict to peek into the flow’s data—at which point the connection has already been established. This can result in connection metadata leaking outside the tunnel, which may contain sensitive information depending on the connection. What is the recommended approach for this use case? NEFilterPacketProvider? This may work, but it has a negative impact on network performance. Using a Packet Tunnel Provider and purely relying on enforceRoutes? Would this indeed ensure that no traffic can leak by targeting a specific interface or by using a second VPN extension? And more broadly—especially if no such approach is currently feasible with the existing APIs—we're interpreting TN3165 as a signal that pf should be considered deprecated and may not be available in the next major macOS release. Is that a reasonable interpretation?
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5
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268
Activity
May ’25
NWConnections in Network Extension Redirected to Proxy
We have a setup where the system uses proxy settings configured via a PAC file. We are investigating how NWConnection behaves inside a Network Extension (NETransparentProxyProvider) with a transparent proxy configuration based on this PAC file. Scenario: The browser makes a connection which the PAC file resolves as "DIRECT" (bypassing the proxy) Our Network Extension intercepts this traffic for analysis The extension creates a new connection using NWConnection to the original remote address. The issue: despite the PAC file’s "DIRECT" decision, NWConnection still respects the system proxy settings and routes the connection through the proxy. Our questions: Is it correct that NWConnection always uses the system proxy if configured ? Does setting preferNoProxies = true guarantee bypassing the system proxy? Additionally: Whitelisting IPs in the Network Extension to avoid interception is not a viable solution because IPs may correspond to multiple services, and the extension only sees IP addresses, not domains (e.g., we want to skip scanning meet.google.com traffic but still scan other Google services on the same IP range). Are there any recommended approaches or best practices to ensure that connections initiated from a Network Extension can truly bypass the proxy (for example, for specific IP ranges or domains)?
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1
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156
Activity
May ’25
How to start a VPN connection with Widget ios 17?
I need to implement a VPN connection from the ios 17 widget without opening the main application. (I have seen such an implementation in other applications) How can this be implemented?
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1
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92
Activity
May ’25
Getting WIFI SSID
Greetings I'm trying to get on iPad the SSID from the wifi I'm connected to. For that, I added the wifi entitlement and I'm requesting permission to the user for Location. Once I have it, I'm using the function CNCopySupportedInterfaces to get the interfaces, but I can only receive the en0, which using the method CNCopyCurrentNetworkInfo returns nil. I also tried using the NEHotspotNetwork.fetchCurrent and the SSID keeps being nil. So right now I'm drawing a blank. Is there any way to make it work? Thanks.
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1
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468
Activity
May ’25
Mac can't find or register NE App Extension without App Sandbox entitlement
Recently, while developing a network extension on macOS, I encountered a very interesting issue. When the App Sandbox entitlement is included, the NE (Network Extension) can be called and run normally. However, when the App Sandbox is removed, with everything else remaining unchanged, an error occurs. The logs are as follows: Failed to find an app extension with identifier app.acmeVpnM.extension and extension point com.apple.networkextension.packet-tunnel: (null) Found 0 registrations for app.acmeVpnM.extension (com.apple.networkextension.packet-tunnel) If you add app sandbox, it will run normally. this is my container app entitlement this is my NE extension (without App SandBox) I want to know the reason for this. App sandbox shouldn't be mandatory. How can I make my NE run in an environment without app sandbox?
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2
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170
Activity
May ’25
Memory release problem of VPN connection object
Hello, I encountered a memory management issue while developing VPN functionality and would like to seek your advice. The specific phenomenon is as follows: Problem description: After multiple calls to the 'createTCPConnectToEndpoint' and 'create UDPSessionToEndpoint' interfaces to create connection objects, the application memory continues to grow. Even if the cancel interface is immediately called to actively release the object, the memory does not fall back. 3. Confirm that there is no other code referencing these objects, but the system does not seem to automatically reclaim memory. Attempted measures: Immediately call the cancel method after creating the object, and the memory is not reduced Use tools such as Profiler to monitor memory and confirm that objects have not been released. doubt: Is this phenomenon normal? Is there a known memory management mechanism (such as cache pooling) that causes delayed release? 2. Are there any other interfaces or methods (such as release, dispose) that need to be explicitly called? Supplementary Information: Development environment: [iOS 16, 14pm] Reproduction steps: After continuously creating connection objects, the memory grows without falling back. Could you please help confirm if there are any abnormalities and the correct memory release posture. Thank you for your support!
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3
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118
Activity
May ’25
Packet Tunnel Provider with Per App VPN debugging
We have a vpn app which uses PacketTunnelProvider. We also support per-app vpn for iOS, I need help with debugging steps for an issue I am facing recently. In the per app vpn, we have split tunneling: some urls should be tunneled while others should be direct, for tunneled urls/ips everything is working as expected. But for "direct" resources, I am facing an issue where sometimes I don't get an ACK back from the browser. Leading to a series of retransmissions and eventually the direct website not loading. Some more points of data: we do get true for the writePackets call, which seems to mean that the vpn app did write the packets to the TUN interface, but we don't get an ACK from the browser. I want some way of debugging this further so I can check if the browser actually got the packets. I also suspect that there might be a loop with packets (we are reading the packets we just wrote onto TUN), but can't say for sure since the issue is intermittent, in case of a loop, I would expect it to always help. Any help would be greatly appreciated.
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3
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194
Activity
May ’25
App occassionally crashing while connecting to public wifi
We are using the [NEHotspotHelper supportedNetworkInterfaces] to get the Wi-Fi interface in our app, but it occasionally crashes on some devices with the following stack trace: 0 CaptiveNetwork 0x0000000221d87a4c ServerConnectionGetHandlerQueue + 0 (ServerConnection.c:509) 1 CaptiveNetwork 0x0000000221d8577c CNPluginCopySupportedInterfaces + 180 (CNPlugin.c:457) 2 NetworkExtension 0x00000001b0446618 +[NEHotspotHelper supportedNetworkInterfaces] + 32 (NEHotspotHelper.m:563) It seems like the crash is happening on apple's api of supportedNetworkInterfaces. We would like to understand the cause of the crash.
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2
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95
Activity
May ’25
NE System Extension stuck on Validation By Category
Hello, I'm having some problems when install my Packet Tunnel network extension as system extension on my mac(macos 15.0). It stuck on Validation By Category. (it works well as NE app extension on ios) systemextensionsctl list --- com.apple.system_extension.network_extension enabled active teamID bundleID (version) name [state] <...> com.myteam.balabalabla.ne (1.0/1) - [validating by category] This is my install System Extension Code sample public class SystemExtension: NSObject, OSSystemExtensionRequestDelegate { private let forceUpdate: Bool private let inBackground: Bool private let semaphore = DispatchSemaphore(value: 0) private var result: OSSystemExtensionRequest.Result? private var properties: [OSSystemExtensionProperties]? private var error: Error? private init(_ forceUpdate: Bool = false, _ inBackground: Bool = false) { } // some request function i overwrite public func activation() throws -> OSSystemExtensionRequest.Result? { let request = OSSystemExtensionRequest.activationRequest(forExtensionWithIdentifier: FilePath.packageName + ".myNeName", queue: .main) request.delegate = self OSSystemExtensionManager.shared.submitRequest(request) semaphore.wait() if let error { throw error } return result } public func getProperties() throws -> [OSSystemExtensionProperties] { let request = OSSystemExtensionRequest.propertiesRequest(forExtensionWithIdentifier: FilePath.packageName + ".myNeName", queue: .main) request.delegate = self OSSystemExtensionManager.shared.submitRequest(request) semaphore.wait() if let error { throw error } return properties! } public nonisolated static func install(forceUpdate: Bool = false, inBackground: Bool = false) async throws -> OSSystemExtensionRequest.Result? { try await Task.detached { try SystemExtension(forceUpdate, inBackground).activation() }.result.get() } public nonisolated static func uninstall() async throws -> OSSystemExtensionRequest.Result? { try await Task.detached { try SystemExtension().deactivation() }.result.get() } } // And other methods I follow this post Your Friend the System Log and use this command line to collect log. After I initiated the system extension request sudo log collect --last 5m Here is my log (),I only pasted some code snippets that caught me, full version see attachments.(only include com.apple.sysextd), if need more, plz ask me. 1. Some policy missing ```log 22:00:13.818257 `sysextd` extension mockTeamID app.balabala.com.mockbalabala (1.0/1) advancing state from staging to validating 22:00:13.818263 sysextd returning cdhash for local arch arm64 of extension app.balabala.com.mockbalabala info 2025-05-01 22:00:13.818336 sysextd Extension with identifier <private> reached state <private> 22:00:13.819185 sysextd [0x9a2034b00] activating connection: mach=false listener=false peer=false name=com.apple.CodeSigningHelper 22:00:13.819911 sysextd [0x9a2034b00] invalidated after the last release of the connection object 22:00:13.821024 sysextd making activation decision for extension with teamID teamID("mockTeamID ), identifier app.balabala.com.mockbalabala 22:00:13.821026 sysextd no related kext found for sysex `app.balabala.com.mockbalabala` 22:00:13.821027 sysextd no extension policy -- activation decision is UserOption nesessionmanager.system-extensions interrupted 22:00:14.313576 sysextd [0x9a2178280] invalidated because the client process (pid 1886) either cancelled the connection or exited 22:00:14.542154 sysextd connection to com.apple.nesessionmanager.system-extensions interrupted 22:00:14.542319 sysextd [0x9a2178000] Re-initialization successful; calling out to event handler with XPC_ERROR_CONNECTION_INTERRUPTED 22:00:14.542351 sysextd connection to com.apple.nesessionmanager.system-extensions interrupted 22:00:14.589375 nesessionmanager [0x6c80e4500] activating connection: mach=true listener=false peer=false name=com.apple.sysextd And when i debug the System Extension code i notice the request Error catch by didFailWithError public func request(_: OSSystemExtensionRequest, didFailWithError error: Error) { self.error = error semaphore.signal() } error is OSSystemExtensionErrorDomain code 1 This problem has been bothering me for a long time, I would appreciate any help, if need more info, comment, thank you.
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3
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296
Activity
May ’25
Non-functioning IP_RECVIF on sockets proxied with NETransparentProxyProvider
Hi! I've noticed that the IP_RECVIF socket option, i.e.: int y = 1; setsockopt(fd, IPPROTO_IP, IP_RECVIF, &y, sizeof(y)); does not seem to work if the socket is proxied by a NETransparentProxyProvider type network extension: there's no ancillary data in messages received with recvmsg. As soon as I disable the network extension, recvmsg starts returning ancillary data containing the interface name. This seems to break some applications which rely on IP_RECVIF in the presence of a transparent proxy, making it, in fact, not transparent. One such example is Apple's own libresolv, which relies on IP_RECVIF and breaks if there's no ancillary data in the recvmsg result. I don't think that this is the intended behaviour, since IPV6_PKTINFO seems to work fine. I've filed a bug report (FB17586550) about this, however, I would greatly appreciate if someone could point me in the direction of a workaround.
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1
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269
Activity
May ’25
wifi connect fail
Dear Apple: In our app, we will call the - (void) applyConfiguration:(NEHotspotConfiguration *) configuration completionHandler:(void (^)(NSError * error)) completionHandler; interface of NEHotspotConfigurationManager on Apple devices. However, we are encountering a problem where the connection to the 2.4G hotspot fails, and the error is nil when it fails. We checked the Wi-Fi air interface and found that the Apple phone does not send a probe request before connecting to the hotspot. However, we are unclear why the Apple device does not send the probe request frame. Could you please help us understand when the probe request frame is not sent during the hotspot connection and how to trigger it to send the probe request frame every time? Thank you.
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4
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143
Activity
May ’25
BGAppRefreshTask Canceled Immediately by dasd in Network Extension
Dear Apple Support Team, My app, io.cylonix.sase, has a BGAppRefreshTask (io.cylonix.sase.ios.refresh) that is canceled by dasd ~9ms after submission from a Network Extension. Please help identify the cause and suggest a solution. App Details: App ID: io.cylonix.sase iOS Version: 17.1.1 (iPhone Xs Max) Network Extension: saseWgNetworkExtension with packet-tunnel-provider entitlement Use Case: VPN app; Network Extension records file receipts in shared group UserDefaults and schedules BGAppRefreshTask to wake the main app. App Usage: High (frequently used) System State: Sufficient resources (not low on battery or memory) Issue: The task is submitted but canceled immediately with priority 10. It has never run, so rate-limiting is not an issue. ` debug 22:09:37.952749-0700 dasd Best binding found for evaluator 0x16d541720: &lt;private&gt; debug 22:09:37.954483-0700 dasd Invoking selector backgroundTaskSchedulerPermittedIdentifiersWithContext:tableID:unitID:unitBytes: on &lt;LSApplicationRecord 0x724844650&gt; default 22:09:37.955563-0700 dasd CANCELED: bgRefresh-io.cylonix.sase.ios.refresh:ABDAFA at priority 10 &lt;private&gt;!
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6
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204
Activity
May ’25
When adding a VPN configuration, the Settings app doesn't continue with the configuration process
Sometimes when adding a VPN configuration, it just redirects to the Settings app and doesn’t continue with the rest of the configuration process like prompting for passcode. But it proceeds as normal after the 2nd or 3rd try. This issue is occurring on iOS 18.5 build 22F5068a but it has been a problem over several versions now. Feedback ID: FB17458055
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1
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154
Activity
May ’25
split Tunnel + exclude APNs
Hello, im currently developing proxy app with XrayCore trying to bypass APNs when tunnel us up and i found .excludeAPNs property in NETunnelProviderProtocol that works only when includeAllNetworks property is also TRUE. I wonder if there is a possible way to make APNs bypass tunnel in split tunnelling mode? because we use excludedRoutes and full tunnel is not an option
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1
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115
Activity
May ’25
Packet Tunnel Provider with Per App VPN debugging
We have a VPN app built using PacketTunnelProvider and support per-app VPN on iOS. We're currently investigating an issue specific to per-app VPN configurations that use split tunneling, where some URLs are routed through the VPN tunnel while others are intended to go directly. Tunneled traffic works as expected. However, for direct traffic, we observe intermittent failures where the browser does not receive an ACK, leading to repeated retransmissions and eventual page load failures. This issue appears only in per-app VPN scenarios, and we've reproduced it across multiple MDM solutions (Intune, CEM) and multiple managed browsers. It's intermittent but frequently reproducible with common public URLs routed directly. Key observations: writePackets returns true, confirming the VPN app writes packets to the TUN interface. Despite that, the browser often fails to acknowledge receipt (no ACK), suggesting it may not receive the packet at all. We suspect a possible packet loop, where packets written to TUN are immediately read back by the app. However, due to the intermittent nature of the issue, this is hard to confirm. A consistent loop would likely result in persistent failures, not sporadic ones. We are attaching: A Wireshark summary - highlighting the missing ACK and retransmission pattern. As we cannot attach the xlsx file or a zip file, we have took the screenshots of the files names as image1, image2, image3, image4 and image5 in sequence. Dails on the iOS device and MDM environment. NETunnelProviderProtocol configuration that reproduces the issue Any guidance on how to further debug this, particularly on confirming packet delivery to the browser and identifying potential loops would be greatly appreciated. Thank you. e t
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3
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120
Activity
May ’25
How to avoid my local server flows in Transparent App Proxy
I have written the Transparent App Proxy and can capture the network flow and send it to my local server. I want to avoid any processing on the traffic outgoing from my server and establish a connection with a remote server, but instead of connecting to the remote server, it again gets captured and sent back to my local server. I am not getting any clue on how to ignore these flows originating from my server. Any pointers, API, or mechanisms that will help me?
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9
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2
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342
Activity
Apr ’25
Rules on AppPushProvider deinitialization
Here's what the documentation says https://developer.apple.com/documentation/networkextension/maintaining-a-reliable-network-connection Confirm that your NEAppPushProvider implementation doesn’t create a retain cycle with itself. After you call the completionHandler that the system passes to stop(with:completionHandler:), the Network Extension framework releases your NEAppPushProvider instance. This instance typically deallocates from memory when released, but if the instance has a retain cycle with itself, it fails to deallocate and wastes memory. Failure to deallocate can also cause the system to have two or more instances of your push provider, leading to inconsistent behavior. Use Instruments or add a logging statement to deinit to verify that your NEAppPushProvider deinitializes when expected. I observe that when I turn off the wifi, the AppPushProvider subclass fully deinitializes. But when I call removeFromPreferences on the NEAppPushManager from the app, it calls stop() on my AppPushProvider subclass, but it does not initialize. Should I be alarmed by this behavior? Will this cause a memory leak? Will this cause multiple Extension/AppPushProviders to be operating concurrently? For testing, I've removed everything except for logs and some singleton calls. No closures capturing self, and no strong references of self being passed anywhere. I am also not using the debugger, and am using the console to debug.
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3
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122
Activity
Apr ’25
Flow Divert behavior
Hello, Our app uses Network Extension / Packet Tunnel Provider to establish VPN connections on macOS and iOS. We have observed that after creating a utun device and adding any IPv4 routes (NEPacketTunnelNetworkSettings.IPv4Settings), the OS automatically adds several host routes via utun to services such as Akamai, Apple Push, etc. These routes appear to correspond to TCP flows that were active at the moment the VPN connection was established. When a particular TCP flow ends, the corresponding host route is deleted. We understand this is likely intended to avoid breaking existing TCP connections. However, we find the behavior of migrating existing TCP flows to the new utun interface simply because any IPv4 route is added somewhat questionable. This approach would make sense in a "full-tunnel" scenario — for example, when all IPv4 traffic (e.g., 0.0.0.0/0) is routed through the tunnel — but not necessarily in a "split-tunnel" configuration where only specific IPv4 routes are added. Is there any way to control or influence this behavior? Would it be possible for FlowDivert to differentiate between full-tunnel and split-tunnel cases, and only preserve existing TCP flows via utun in the full-tunnel scenario? Thank you.
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115
Activity
Apr ’25