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

If an app has a text filtering extension and associated server that the iPhone OS communicates with, then how can that communication be authenticated? In other words, how can the server verify that the request is valid and coming from the iPhone and not from some spoofer? If somebody reverse engineers the associated domain urls our of the app's info.plist or entitlement files and calls the server url directly, then how can the server detect this has occurred and the request is not coming from the iPhone OS of a handset on which the app is installed?

Hi, We have an issue (https://github.com/actions/runner-images/issues/10924) raised by a user requesting to add 'local network access' permission for macOS 15 and macOS 15-arm64 image runners. Apple introduced a new LNP policy with macOS Sequoia that is not controlled by TCC or MDM. Could you please guide us on how to add 'local network access' permission for macOS 15 and macOS 15-arm64 image runners? Thanks.

I'm trying to detect the state of Local Network privacy on macOS Sequoia via NWBrowser, as recommended in https://developer.apple.com/documentation/technotes/tn3179-understanding-local-network-privacy Regardless of the state of Local Network privacy - undetermined, allowed or denied, NWBrowser receives an update indicating that its in the ready state. Scanning does not seem to trigger the Local Network privacy alert for me - I have to use the other recommended method to trigger the prompt. Enabling or disabling Local Network privacy does not seem to send any updates for NWBrowser. https://developer.apple.com/forums/thread/666431 seems related, and implies that they did receive further updates to NWBrowser. Filed as FB16077972

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

With the new macOS 15, Apple introduced the new Local Network Privacy feature. This is causing issues for our customers as - even though they granted the required permission for our software - connections to a server in their local network are being blocked. The situation is not fixed by recent macOS updates. As far as I know, this issue exists for machines running on Apple Silicon. Systems running macOS versions (e.g. Sonoma) are not affected. Currently, the workaround is to re-enable the permission under Settings > Privacy & Security > Local Network. The list shows our application with an enabled checkbox. Users now have to de-select the box and then re-select it again for the application to work. They have to do this after each and every reboot of their system, which is slightly annoying (so at the moment we recommend to not upgrade macOS to Sequoia, if possible) I did some research and saw that other products are also affected by this bug. Is there a solution to this issue or any plans to fix it?

In order to create a Message Filter Extension it is necessary to set up Shared Web Credentials. I'd like to form an understanding of what role SWC plays when the OS is making request to the associated network service (when the extension has called deferQueryRequestToNetwork()) and how this differs from when an app directly uses Shared Web Credentials itself. When an app is making direct use of SWC, it makes a request to obtain the user's credentials from the web site. However in the case of a Message Filter Extension, there aren't any individual user credentials, so what is happening behind the scenes when the OS makes a server request on behalf of a Message Filtering Extension? A more general question - the documentation for Shared Web Credentials says "Associated domains establish a secure association between domains and your app.". Thank you

I am writing an app using Microsoft's MAUI platform. I am posting this here because that team wants me to make an xcode project to help determine an issue I am having. My MAUI app sends a broadcast packet on a UDP socket using address 255.255.255.255. This worked fine in iOS version 17.x. After upgrading my phone to iOS 18.x it stopped working. The error I get is "no route to host". The exact same code works fine on MacOS. It does not work on iPadOs 18. My question here is 3 fold: Did something specific change between iOS 17 and 18 that would cause a 'no route to host' error when sending a UDP broadcast packet? Can someone provide sample code to show me how to do this type of broadcast using Swift in Xcode for iOS? I read an article that said my app would need the com.apple.developer.networking.multicast entitlement in order to use boradcast functionality. This was introduced in iOS 14. Why did my app work fine in iOS 17 then? Is this what changed? Did this requirement use to be optional and is now required? I did get this entitlement from Apple and applied it to my provisioning profile and my app gave the same "no route to host" error. Why?

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

Hello Everyone, I'm currently working on a cross-platform application that uses IP-based multicast for device discovery across both Apple and non-Apple devices running the same app. All devices join a multicast group "X.X.X.X" on port Y. For Apple devices, I am using NWConnectionGroup for multicast discovery, while for non-Apple devices, I am using BSD sockets. The issue arises when I attempt to send a multicast message to the group using NWConnectionGroup. The message is sent from a separate ephemeral port rather than the multicast port Y. As a result, all Apple processes that are using NWConnectionGroup can successfully receive the multicast message. However, the processes running on the non-Apple devices (using BSD sockets) do not receive the message. My Questions: Is there a way to configure NWConnectionGroup to send multicast messages from the same multicast port Y rather than an ephemeral port? Is there any known behavior or limitation in how NWConnectionGroup handles multicast that could explain why non-Apple devices using BSD sockets cannot receive the message? How can I ensure cross-platform multicast compatibility between Apple devices using NWConnectionGroup and non-Apple devices using BSD sockets? Any guidance or suggestions would be greatly appreciated! Thanks, Harshal

Our company has a VPN client that uses the Packet Tunnel Provider network extension and when 18 came out we noticed that we were no longer seeing DNS requests get sent to the VPNs TUN interface. Do a packet trace, once the VPN becomes active we see requests to _dns.resolver.arpa and 12-courier.push.apple.com, which both get resolved as expected. Also our main app that controls the VPN service and does authentication has to resolve a hostname to get to an authentication service and we see those requests just fine as well. However, when we try to resolve by going to a webpage in Safari we see no DNS request corresponding to that. What are we missing? At first I thought it was the RFC9461 stuff but from the packet traces I don't believe that is the case. I have also tried other networking tools to send the DNS requests and that failed as well.

I'm developing in Swift and working on parsing DNS queries. I'm considering using dns_parse_packet, but I noticed that dns_util is deprecated (although it still seems to work in my limited testing). As far as I know, there isn’t a built-in replacement for this. Is that correct? On a related note, are there any libraries available for parsing TLS packets—specifically the ClientHello message to extract the Server Name Indication (SNI)—instead of relying on my own implementation? Related to this post.

sometimes app from background to foreground , then send a Http request will got network lost response, and if you delay 0.1 seconds to send request, it's work fine. Does any one can explian this?

Hi, I have a problem about "NSPOSIXErrorDomain Code=65 & iOS18 & Xcode 16". I used 'CocoaAsyncSocket', '~> 7.6.5'. It works fine on iOS 15.2， But it's worried on iOS 18.3. Before this, broadcasts can be obtained normally。 I had get socket Multicast Networking. Please help me .

I've implemented a custom system extension VPN for macOS, using a Packet Tunnel Provider. I saw something suspicious on macOS 15.2.0: When I disconnected my VPN, the UTUN was not being cleared. This results in a lot of UTUNs when the user connects and disconnects multiple times. utun77: flags=8051<UP,POINTOPOINT,RUNNING,MULTICAST> mtu 1500 utun78: flags=8051<UP,POINTOPOINT,RUNNING,MULTICAST> mtu 1500 This happens only on macOS 15.2. I tried the same app on older versions (15.0, 15.1.x), and it didn't reproduce. Can those 'dirty' UTUNs cause a networking problem? Since it happens only on macOS 15.2, is there a bug in this OS version? How can I check if something in my code causes this behavior? How can I 'fix' it or force clean the 'dirty' UTUNs?

I have been battling this intermittent error for some time. It is generally random and has been difficult to reproduce until yesterday when I stumbled across a way to reproduce it each time. I can cause the code to throw this error: Task <70E3909F-8C30-4F34-A8B0-4AF3B41DD81B>.<1> finished with error [-1001] Error Domain=NSURLErrorDomain Code=-1001 "The request timed out." UserInfo={_kCFStreamErrorCodeKey=-2103, _NSURLErrorFailingURLSessionTaskErrorKey=BackgroundDownloadTask <70E3909F-8C30-4F34-A8B0-4AF3B41DD81B>.<1>, _NSURLErrorRelatedURLSessionTaskErrorKey=( "BackgroundDownloadTask <70E3909F-8C30-4F34-A8B0-4AF3B41DD81B>.<1>", "LocalDownloadTask <70E3909F-8C30-4F34-A8B0-4AF3B41DD81B>.<1>" ), NSLocalizedDescription=The request timed out., _kCFStreamErrorDomainKey=4, NSErrorFailingURLStringKey=https://redacted*, NSErrorFailingURLKey=https://redacted*} *"redacted" is the backend URL, and it is the correct and same path for each immediately after restarting an actual device. I have been over the following threads with no results: What is kCFStreamErrorCodeKey=-4 (kCFStreamErrorDomainKey=4) Request timed out with _kCFStreamErrorCodeKey=60 How to better diagnose -1001 "The request timed out." URLSession errors Random timed out error on app start Because I was able to reproduce it, I have been able to get the following logs: Console Logs.txt Last bit of information is that I had Network Instruments running, and when this error occurred, I found that the Connection ID was "No Connection" and it appears the request was never actually sent, though it waited the full time out for a backend response. Any help would be appreciated. This data request is being used after sending a certain APNs to update necessary data in the background, and has been the source of many user complaints.

"NSPOSIXErrorDomain Code=65 & iOS18 & Xcode 16". I used 'CocoaAsyncSocket', '~> 7.6.5'. It works fine on 13pro iOS16.4.1 &iphone x 16.7.7， But it's bad on iOS 18.3.

Hi, I have a problem with my Mac crashing sims 4. can you let me know if this is a Mac problem or a sims 4 problem ? Link to Mac Info : https://prnt.sc/NYG0jn8_u0dB Link to crash report : https://prnt.sc/UImzDIsqdVYn

Hi everyone, We are working on creating a virtual network interface using NEPacketTunnelProvider, with an MTU of 1500 bytes. I would like to understand what will happen if we attempt to write packets of approximately 65,000 bytes to this interface. Specifically, will the packets be fragmented based on protocol and flags, will they be dropped, or is there another unexpected behaviour we should anticipate? Thanks

We updated the apple-app-site-association file two weeks ago and we are only seeing the new content from Apple's CDN serving certain regions such as Texas and Canada. Regions such as Colorado intermittently sees the old content and California has been receiving the old content all the time. Is this a known issue? If yes, when can we expect this to be fixed and where to check the status? If not, can someone in charge of CDN please look into this? Let me know if there is a better place to report this issue and get the support ASAP though. Thank you in advance and happy new year!