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

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

Could anyone tell me how to detect status of Local Network for iOS 18+ systems ?

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

I've been wondering what is the memory limit for network extensions. Specifically, I'm using the NEPacketTunnelProvider extension point.The various posts on this forum mention 5 MB and 6 MB for 32-bit and 64-bit respectively. However I find that (at least on iOS 10) the upper limit seems to be 15 MB. Is this the new memory limit for extensions?

Hello Everyone, I’m working on a project that involves multicast communication between processes running on different devices within the same network. For all my Apple devices (macOS, iOS, etc.), I am using NWConnectionGroup, which listens on a multicast address "XX.XX.XX.XX" and a specific multicast port. The issue occurs when a requestor (such as a non-Apple process) sends a multicast request, and the server, which is a process running on an Apple device using NWConnectionGroup (the responder), attempts to reply. The problem is that the response is sent from a different ephemeral port rather than the port on which the multicast request was received. If the client is behind a firewall that blocks unsolicited traffic, the firewall only allows incoming packets on the same multicast port used for the initial request. Since the multicast response is sent from a different ephemeral port, the firewall blocks this response, preventing the requestor from receiving it. Questions: Is there a recommended approach within the NWConnectionGroup or Network.framework to ensure that responses to multicast requests are sent from the same port used for the request? Are there any best practices for handling multicast responses in scenarios where the requestor is behind a restrictive firewall? Any insights or suggestions on how to account for this behavior and ensure reliable multicast communication in such environments would be greatly appreciated. Thanks, Harshal

I want to configure one aspect of my networking configuration (the QUIC keepalive interval). This only seems to be configurable via Network.framework’s nw_quic_set_keepalive_interval. Is there any way to apply this to a URLSession? Or do I need to implement the whole connection management myself using Network.framework?

Hello, Since the release of iOS 26.0, we are seeing DNS traffic being blocked from within our NEPacketTunnelExtension on some devices. We have not isolated exact reproduction steps, but DNS resolves successfully for a period of time after enabling "iCloud Private Relay" (varying from 1-day to 2-weeks), until it then fails as MDNSResponder then returns: mDNSResponder [Q37046] DetermineUnicastQuerySuppression: Query suppressed for <mask.hash: 'REDACTED'> Addr (blocked by policy) DNS resolution continues to fail for all domains with the above until the device is rebooted. The Packet Tunnel intentionally does not have a DNS server set and this occurs for traffic from the Extension yet off-tunnel, which needs resolution from the system DNS server (and this configuration works perfectly for a period of time before being "blocked by policy"). The following do not resolve the issue once DNS queries are being "blocked by policy" on affected devices: disconnecting then reconnecting the vpn; toggling airplane mode for 10+ seconds; switching connection between WiFi & cellular data; disabling iCloud Private Relay. We have currently only seen this on unmanaged devices running iOS 26.0 or 26.1 beta and with iCloud Private Relay enabled. We did not see this issue on iOS 16,17 nor 18. We also have not yet seen this when iCloud Private Relay is disabled nor on iOS 26.0.1, however we cannot confirm whether they too are also affected. Is there a known a bug with iOS 26.0 & 26.1 Beta 1 that could cause this? How can we prevent DNS requests from NEPacketTunnelExtension being sporadically "blocked by policy" until the device is rebooted? Many thanks in advance.

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

iPhone 12 pro with iOS 26.0 (23A5276f) App: https://developer.apple.com/documentation/wifiaware/building-peer-to-peer-apps We aim to use Wi-Fi Aware to establish file transfer between Android and Apple devices. Apple will act as the Publisher, and Android will act as the Subscriber. According to the pairing process outlined in the Wi-Fi Aware protocol (Figure 49 in the Wi-Fi Aware 4.0 specification), the three PASN Authentication frames have been successfully exchanged. Subsequently, Android sends the encrypted Follow-up PMF to Apple, but the Apple log shows: Failed to parse event. Please refer to the attached complete log. We request Apple to provide a solution. apple Log-20250808a.txt

how can I prevent handshake when certificate is user installed for example if user is using Proxyman or Charles proxy and they install their own certificates now system is trusting those certificates I wanna prevent that, and exclude those certificates that are installed by user, and accept the handshake if CA certificate is in a real valid certificate defined in OS I know this can be done in android by setting something like <network-security-config> <base-config> <trust-anchors> <certificates src="system" /> </trust-anchors> </base-config> </network-security-config>

For a past few days, I have been exploring control Filter and data filter. I am unable to understand how control moves from various functions of data filter to control Filter. One thing that I am unable to figure out is that when I pass verdict as .allow in dataFilter's handleNewFlow and mark .shouldReport as true, I get inBytes and outbytes in the flow report of handle() in controlFilter. But when I pass verdict as needRules and wait till the handle is called in controlFilter when the report.event == .flowClosed, I don't get inBytes and outBytes. I am unable to understand this complete flow of network extension from the apple documentation. Can someone provide me with some flow chart or some pictorial representation or detailed explanation of network extension for iOS? Also is there some way to imitate the ..statisticsReportFrequency for iOS as it is not available for iOS?

NWPathMonitor appears to retain itself (or is retained by some internal infrastructure) once it has been started until cancelled. This seems like it can lead to memory leaks if the references to to the monitor are dropped. Is this behavior documented anywhere? func nwpm_self_retain() { weak var weakRef: NWPathMonitor? autoreleasepool { let monitor: NWPathMonitor = NWPathMonitor() weakRef = monitor monitor.start(queue: .main) // monitor.cancel() // assertion fails unless this is called } assert(weakRef == nil) } nwpm_self_retain()

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?

If the includeAllNetworks flag to true, we cannot update our app via Xcode, TestFlight or the AppStore. In the AppStore and TestFlight cases, it seems that the packet tunnel process is stopped before the new app is downloaded - once the packet tunnel process is stopped, it can’t be started again via Settings/VPN profiles, nor can it be started via the app.

Hey everyone, I’m developing an app for visionOS where I need to display the Apple Vision Pro’s current IP address. For this I’m using the following code, which works for iOS, macOS, and visionOS in the simulator. Only on a real Apple Vision Pro it’s unable to extract an IP. Could it be that visionOS currently doesn’t allow this? Have any of you had the same experience and found a workaround? var address: String = "no ip" var ifaddr: UnsafeMutablePointer<ifaddrs>? = nil if getifaddrs(&ifaddr) == 0 { var ptr = ifaddr while ptr != nil { defer { ptr = ptr?.pointee.ifa_next } let interface = ptr?.pointee let addrFamily = interface?.ifa_addr.pointee.sa_family if addrFamily == UInt8(AF_INET) { if let name: Optional<String> = String(cString: (interface?.ifa_name)!), name == "en0" { var hostname = [CChar](repeating: 0, count: Int(NI_MAXHOST)) getnameinfo(interface?.ifa_addr, socklen_t((interface?.ifa_addr.pointee.sa_len)!), &hostname, socklen_t(hostname.count), nil, socklen_t(0), NI_NUMERICHOST) address = String(cString: hostname) } } } freeifaddrs(ifaddr) } return address } Thanks in advance for any insights or tips! Best Regards, David

Hi everyone, I'm currently working on a project where I need to send multicast packets across all available network interfaces using Apple Network Framework's NWConnectionGroup. Specifically, the MacBook (device I am using for sending multicast requests, MacOS: 15.1) is connected to two networks: Wi-Fi (Network 1) and Ethernet (Network 2), and I need to send multicast requests over both interfaces. I tried using the .requiredInterface property as suggested by Eskimo in this post, but I’m running into issues. It seems like I can't create an NWInterface object because it doesn't have any initializers. Here is the code which I wrote: var multicast_group_descriptor : NWMulticastGroup var multicast_endpoint : NWEndpoint multicast_endpoint = NWEndpoint.hostPort(host: NWEndpoint.Host("234.0.0.1"), port: NWEndpoint.Port(rawValue: 49154)!) var connection_group : NWConnectionGroup var multicast_params : NWParameters multicast_params = NWParameters.udp var interface = NWInterface(NWInterface.InterfaceType.wiredEthernet) I get following error: 'NWInterface' cannot be constructed because it has no accessible initializers I also experimented with the .requiredInterfaceType property. Even when I set it to .wiredEthernet and then change it to .wifi, I am still unable to send requests over the Wi-Fi network. Here is the code I wrote: var multicast_params : NWParameters multicast_params = NWParameters.udp multicast_params.allowLocalEndpointReuse = true multicast_params.requiredInterfaceType = .wiredEthernet var ip = multicast_params.defaultProtocolStack.internetProtocol! as! NWProtocolIP.Options ip.disableMulticastLoopback = true connection_group = NWConnectionGroup(with: multicast_group_descriptor, using: multicast_params) connection_group.stateUpdateHandler = { state in print(state) if state == .ready { connection_group.send(content: "Hello from machine on 15".data(using: .utf8)) { error in print("Send to mg1 completed on wired Ethernet with error \(error?.errorCode)") var params = connection_group.parameters params.requiredInterfaceType = .wifi connection_group.send(content: "Hello from machine on 15 P2 on Wi-Fi".data(using: .utf8)) { error in print("Send to mg1 completed on Wi-Fi with error \(error?.errorCode)") } } } } Is this expected behavior when using NWConnectionGroup? Or is there a different approach I should take to ensure multicast requests are sent over both interfaces simultaneously? Any insights or suggestions would be greatly appreciated! Thanks in advance, Harshal

Simulator: iPhone 16 pro (iOS 26) Minimum Deployments: iOS 16.0+, not iOS 17. Here is the demo: import SwiftUI import NetworkExtension struct ContentView: View { private var monitor = NWPathMonitor() var body: some View { VStack { Text("Hello, world!") } .task { let _ = URLSession.shared } } }

Hello! I develop transparent proxy based application, and I'm receiving a lot of crash reports from macOS 15.5 for crash in __88-[NEExtensionAppProxyProviderContext setInitialFlowDivertControlSocket:extraValidation:]_block_invoke.90 when stopping. Even very old versions of my software started crashing on macOS 15.5. I checked my extension that it correctly calls setTunnelNetworkSettings:nil on proxy stop, but crash is still here. Does anybody else have this problem? Do you know any workaround for it?

I'm developing an application using the accessory setup kit (BLE) on iOS 18+. An important aspect of the connection process is being able to find and choose the correct device. I noticed on iOS 18.2 that I was able to both scroll through the discovered accessories as well as view the advertised name. However, after upgrading to 18.7.2, only a single device is viewable and the advertised name is no longer available. Is there a trigger for this feature that I need to enable or was this "multiple discovery" feature removed? If so, why?