I haven’t come across any official documentation regarding the limit on the number of Network Extensions macOS can run. However, I did see some discussions suggesting that Apple might restrict this to 5 extensions in macOS Tahoe.
Is there any official confirmation on this?
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Hi,
We're hoping someone can help us determine why we're running into some odd behavior where a simple HTTP request is intermittently failing with error code NSURLErrorTimedOut (-1001)
Background:
HTTP request details:
The request is sent from a PacketTunnelProvider and is meant to be a Captive Portal check.
The request is insecure (HTTP, instead of HTTPS) but we have configured App Transport Security (ATS) to allow insecure HTTP loads from this hostname.
See info.plist excerpt below.
The request is sent using NSMutableURLRequest/NSURLSessionDataTask using an Ephemeral session configuration.
We only modify 2 properties on NSMutableURLRequest
The timeoutInterval property is set to 5 seconds.
The allowsCellularAccess property is set to NO.
No headers or other configuration are modified.
NSURLSessionDataTask completionHandler receives an NSError:
We checked the NSError's userInfo dictionary for an underlying error (NSUnderlyingErrorKey).
The underlying error shows the same code NSURLErrorTimedOut (-1001).
We haven't seen any underlying errors with code NSURLErrorAppTransportSecurityRequiresSecureConnection (-1022) .
On a laptop, we confirmed that the Captive portal check site is accessible and loads correctly.
Laptop and iOS device are on the same Wi-fi.
I've witnessed the error in the debugger, and been able to load the site on my laptop at the same time.
So, we don't have any reason to believe this is server related.
The PacketTunnelProvider is configured to only handle DNS queries and is not intercepting/routing the HTTP traffic.
The DNS query for the Captive portal request is handled correctly.
In fact, outside of the PacketTunnelProvider, all sites load in Mobile Safari.
So, we're not breaking internet on this device.
In other words, we have no reason to believe our DNS handling is interfering with the HTTP request since other HTTP requests are working as expected.
We setup CFNetwork Diagnostic Logging (https://developer.apple.com/documentation/network/debugging-https-problems-with-cfnetwork-diagnostic-logging)
In console.app, we are able to find some logging on the Timeout
See excerpt from Console.app's log below.
We confirmed that the nscurl tool did not flag the request (https://developer.apple.com/documentation/security/identifying-the-source-of-blocked-connections)
All ATS tests run with nscurl were successful.
See nscurl command used below.
Questions:
What are next steps to debug this intermittent timeout?
What should we look for in the CFNetwork Diagnostic Logging to help debug the issue further?
Thanks in advance for your help!
ATS configuration setup in both the UI and the PacketTunnel's info.plist file:
<key>NSAppTransportSecurity</key>
<dict>
<key>NSExceptionDomains</key>
<dict>
<key>subdomain.subdomain.example.com</key>
<dict>
<key>NSExceptionAllowsInsecureHTTPLoads</key>
<true/>
<key>NSIncludesSubdomains</key>
<true/>
</dict>
</dict>
</dict>
Excerpt from Console.app's log:
CFNetwork Example PacketTunnel 10836 Diagnostics default 11:30:33.029032-0700 CFNetwork Diagnostics [3:834] 11:30:32.946 {
Did Timeout: (null)
Loader: request GET http://subdomain.subdomain.example.com/content/cpcheck.txt HTTP/1.1
Timeout Interval: 5.000 seconds
init to origin load: 0.000592947s
total time: 5.00607s
total bytes: 0
} [3:834]
nscurl command
$ /usr/bin/nscurl --ats-diagnostics --verbose http://subdomain.subdomain.example.com/content/cpcheck.txt
Before iOS16, we can use
https://developer.apple.com/documentation/coretelephony/ctcarrier
But after iOS this is deprecated and has no replacement.
There are some discussions on it, eg.
https://developer.apple.com/forums/thread/714876
https://developer.apple.com/forums/thread/770400
Now I asked AI, then it provided this solution, to check the serviceCurrentRadioAccessTechnology, so it this ok to check the SIM card status?
var hasSIMCard = false
let info = CTTelephonyNetworkInfo()
if let rat = info.serviceCurrentRadioAccessTechnology,
rat.values.contains(where: { !$0.isEmpty }) {
hasSIMCard = true. // has RAT
}
BTW, I can see a lot of changes in the Core Telephony framework.
https://developer.apple.com/documentation/coretelephony
1.isSIMInserted
https://developer.apple.com/documentation/coretelephony/ctsubscriber/issiminserted
A Boolean property that indicates whether a SIM is present. iOS 18.0+ iPadOS 18.0+
This value property is true if the system finds a SIM matching the Info.plist carrier information (MCC / MNC / GID1 / GID2).
Is this ok to check SIM insert status, this seems must preconfig some info in the info.plist.
2.iOS26 provide CTCellularPlanStatus
https://developer.apple.com/documentation/coretelephony/ctcellularplanstatus
Can I use this to check SIM status?
I am trying to convert a simple URLSession request in Swift to using NWConnection. This is because I want to make the request using a Proxy that requires Authentication. I posted this SO Question about using a proxy with URLSession. Unfortunately no one answered it but I found a fix by using NWConnection instead.
Working Request
func updateOrderStatus(completion: @escaping (Bool) -> Void) {
let orderLink = "https://shop.ccs.com/51913883831/orders/f3ef2745f2b06c6b410e2aa8a6135847"
guard let url = URL(string: orderLink) else {
completion(true)
return
}
let cookieStorage = HTTPCookieStorage.shared
let config = URLSessionConfiguration.default
config.httpCookieStorage = cookieStorage
config.httpCookieAcceptPolicy = .always
let session = URLSession(configuration: config)
var request = URLRequest(url: url)
request.httpMethod = "GET"
request.setValue("text/html,application/xhtml+xml,application/xml;q=0.9,*/*;q=0.8", forHTTPHeaderField: "Accept")
request.setValue("none", forHTTPHeaderField: "Sec-Fetch-Site")
request.setValue("navigate", forHTTPHeaderField: "Sec-Fetch-Mode")
request.setValue("Mozilla/5.0 (Macintosh; Intel Mac OS X 10_15_7) AppleWebKit/605.1.15 (KHTML, like Gecko) Version/18.0.1 Safari/605.1.15", forHTTPHeaderField: "User-Agent")
request.setValue("en-US,en;q=0.9", forHTTPHeaderField: "Accept-Language")
request.setValue("gzip, deflate, br", forHTTPHeaderField: "Accept-Encoding")
request.setValue("document", forHTTPHeaderField: "Sec-Fetch-Dest")
request.setValue("u=0, i", forHTTPHeaderField: "Priority")
// make the request
}
Attempted Conversion
func updateOrderStatusProxy(completion: @escaping (Bool) -> Void) {
let orderLink = "https://shop.ccs.com/51913883831/orders/f3ef2745f2b06c6b410e2aa8a6135847"
guard let url = URL(string: orderLink) else {
completion(true)
return
}
let proxy = "resi.wealthproxies.com:8000:akzaidan:x0if46jo-country-US-session-7cz6bpzy-duration-60"
let proxyDetails = proxy.split(separator: ":").map(String.init)
guard proxyDetails.count == 4, let port = UInt16(proxyDetails[1]) else {
print("Invalid proxy format")
completion(false)
return
}
let proxyEndpoint = NWEndpoint.hostPort(host: .init(proxyDetails[0]),
port: NWEndpoint.Port(integerLiteral: port))
let proxyConfig = ProxyConfiguration(httpCONNECTProxy: proxyEndpoint, tlsOptions: nil)
proxyConfig.applyCredential(username: proxyDetails[2], password: proxyDetails[3])
let parameters = NWParameters.tcp
let privacyContext = NWParameters.PrivacyContext(description: "ProxyConfig")
privacyContext.proxyConfigurations = [proxyConfig]
parameters.setPrivacyContext(privacyContext)
let host = url.host ?? ""
let path = url.path.isEmpty ? "/" : url.path
let query = url.query ?? ""
let fullPath = query.isEmpty ? path : "\(path)?\(query)"
let connection = NWConnection(
to: .hostPort(
host: .init(host),
port: .init(integerLiteral: UInt16(url.port ?? 80))
),
using: parameters
)
connection.stateUpdateHandler = { state in
switch state {
case .ready:
print("Connected to proxy: \(proxyDetails[0])")
let httpRequest = """
GET \(fullPath) HTTP/1.1\r
Host: \(host)\r
Connection: close\r
Accept: text/html,application/xhtml+xml,application/xml;q=0.9,*/*;q=0.8\r
User-Agent: Mozilla/5.0 (Macintosh; Intel Mac OS X 10_15_7) AppleWebKit/605.1.15 (KHTML, like Gecko) Version/18.0.1 Safari/605.1.15\r
Accept-Language: en-US,en;q=0.9\r
Accept-Encoding: gzip, deflate, br\r
Sec-Fetch-Dest: document\r
Sec-Fetch-Mode: navigate\r
Sec-Fetch-Site: none\r
Priority: u=0, i\r
\r
"""
connection.send(content: httpRequest.data(using: .utf8), completion: .contentProcessed({ error in
if let error = error {
print("Failed to send request: \(error)")
completion(false)
return
}
// Read data until the connection is complete
self.readAllData(connection: connection) { finalData, readError in
if let readError = readError {
print("Failed to receive response: \(readError)")
completion(false)
return
}
guard let data = finalData else {
print("No data received or unable to read data.")
completion(false)
return
}
if let body = String(data: data, encoding: .utf8) {
print("Received \(data.count) bytes")
print("\n\nBody is \(body)")
completion(true)
} else {
print("Unable to decode response body.")
completion(false)
}
}
}))
case .failed(let error):
print("Connection failed for proxy \(proxyDetails[0]): \(error)")
completion(false)
case .cancelled:
print("Connection cancelled for proxy \(proxyDetails[0])")
completion(false)
case .waiting(let error):
print("Connection waiting for proxy \(proxyDetails[0]): \(error)")
completion(false)
default:
break
}
}
connection.start(queue: .global())
}
private func readAllData(connection: NWConnection,
accumulatedData: Data = Data(),
completion: @escaping (Data?, Error?) -> Void) {
connection.receive(minimumIncompleteLength: 1, maximumLength: 65536) { data, context, isComplete, error in
if let error = error {
completion(nil, error)
return
}
// Append newly received data to what's been accumulated so far
let newAccumulatedData = accumulatedData + (data ?? Data())
if isComplete {
// If isComplete is true, the server closed the connection or ended the stream
completion(newAccumulatedData, nil)
} else {
// Still more data to read, so keep calling receive
self.readAllData(connection: connection,
accumulatedData: newAccumulatedData,
completion: completion)
}
}
}
In my app I have Local Push connectivity for local push notifications. My app has proper entitlment granted by Apple and NEAppPushProvider was working perfectly on older iOS versions before iOS26.
The problem I faced with iOS26: when i enable VPN - NEAppPushProvider stops with reason
/** @const NEProviderStopReasonNoNetworkAvailable There is no network connectivity. */
case noNetworkAvailable = 3.
But device is still connected to proper SSID that is included to matchSSIDs.
I discovered it only happens if my VPN config file include this line
redirect-gateway def1
without that line NEAppPushProvider works as expected with enabled VPN.
I use OpenVPN app.
Is it a bug of iOS26 or I need some additional setup?
Please help!
1、已经检查过手机的存储空间,还有一百多G的空间。app端进行网络接口情况的时候报错了,报错信息如下:
Error : Error Domain=NSPOSIXErrorDomain Code=28 "No space left on device" UserInfo={_NSURLErrorFailingURLSessionTaskErrorKey=LocalDataTask <7DB1CBFD-B9BE-422D-9C9A-78D8FC04DC1B>.<76>, _kCFStreamErrorDomainKey=1, _kCFStreamErrorCodeKey=28, _NSURLErrorRelatedURLSessionTaskErrorKey=(
"LocalDataTask <7DB1CBFD-B9BE-422D-9C9A-78D8FC04DC1B>.<76>"
), _NSURLErrorNWPathKey=satisfied (Path is satisfied), interface: pdp_ip0[lte], ipv4, ipv6, dns, expensive, estimated upload: 65536Bps, uses cell}
2、手机型号是iPhone 15 Plus,iOS 17.6.1
Topic:
App & System Services
SubTopic:
Networking
I am trying to activate an application which sends my serial number to a server. The send is being blocked. The app is signed but not sandboxed.
I am running Sequoia on a recent iMac. My network firewall is off and I do not have any third party virus software. I have selected Allow Applications from App Store & Known Developers.
My local network is wifi using the eero product. There is no firewall or virus scanning installed with this product.
Under what circumstances will Mac OS block outgoing internet connections from a non-sandboxed app? How else could the outgoing connection be blocked?
Topic:
App & System Services
SubTopic:
Networking
Most apps perform ordinary network operations, like fetching an HTTP resource with URLSession and opening a TCP connection to a mail server with Network framework. These operations are not without their challenges, but they’re the well-trodden path.
If your app performs ordinary networking, see TN3151 Choosing the right networking API for recommendations as to where to start.
Some apps have extra-ordinary networking requirements. For example, apps that:
Help the user configure a Wi-Fi accessory
Require a connection to run over a specific interface
Listen for incoming connections
Building such an app is tricky because:
Networking is hard in general.
Apple devices support very dynamic networking, and your app has to work well in whatever environment it’s running in.
Documentation for the APIs you need is tucked away in man pages and doc comments.
In many cases you have to assemble these APIs in creative ways.
If you’re developing an app with extra-ordinary networking requirements, this post is for you.
Note If you have questions or comments about any of the topics discussed here, put them in a new thread here on DevForums. Make sure I see it by putting it in the App & System Services > Networking area. And feel free to add tags appropriate to the specific technology you’re using, like Foundation, CFNetwork, Network, or Network Extension.
Links, Links, and More Links
Each topic is covered in a separate post:
The iOS Wi-Fi Lifecycle describes how iOS joins and leaves Wi-Fi networks. Understanding this is especially important if you’re building an app that works with a Wi-Fi accessory.
Network Interface Concepts explains how Apple platforms manage network interfaces. If you’ve got this far, you definitely want to read this.
Network Interface Techniques offers a high-level overview of some of the more common techniques you need when working with network interfaces.
Network Interface APIs describes APIs and core techniques for working with network interfaces. It’s referenced by many other posts.
Running an HTTP Request over WWAN explains why most apps should not force an HTTP request to run over WWAN, what they should do instead, and what to do if you really need that behaviour.
If you’re building an iOS app with an embedded network server, see Showing Connection Information in an iOS Server for details on how to get the information to show to your user so they can connect to your server.
Many folks run into trouble when they try to find the device’s IP address, or other seemingly simple things, like the name of the Wi-Fi interface. Don’t Try to Get the Device’s IP Address explains why these problems are hard, and offers alternative approaches that function correctly in all network environments.
Similarly, folks also run into trouble when trying to get the host name. On Host Names explains why that’s more complex than you might think.
If you’re working with broadcasts or multicasts, see Broadcasts and Multicasts, Hints and Tips.
If you’re building an app that works with a Wi-Fi accessory, see Working with a Wi-Fi Accessory.
If you’re trying to gather network interface statistics, see Network Interface Statistics.
There are also some posts that are not part of this series but likely to be of interest if you’re working in this space:
TN3179 Understanding local network privacy discusses the local network privacy feature.
Calling BSD Sockets from Swift does what it says on the tin, that is, explains how to call BSD Sockets from Swift. When doing weird things with the network, you often find yourself having to use BSD Sockets, and that API is not easy to call from Swift. The code therein is primarily for the benefit of test projects, oh, and DevForums posts like these.
TN3111 iOS Wi-Fi API overview is a critical resource if you’re doing Wi-Fi specific stuff on iOS.
TLS For Accessory Developers tackles the tricky topic of how to communicate securely with a network-based accessory.
A Peek Behind the NECP Curtain discusses NECP, a subsystem that control which programs have access to which network interfaces.
Networking Resources has links to many other useful resources.
Share and Enjoy
—
Quinn “The Eskimo!” @ Developer Technical Support @ Apple
let myEmail = "eskimo" + "1" + "@" + "apple.com"
Revision History
2025-07-31 Added a link to A Peek Behind the NECP Curtain.
2025-03-28 Added a link to On Host Names.
2025-01-16 Added a link to Broadcasts and Multicasts, Hints and Tips. Updated the local network privacy link to point to TN3179. Made other minor editorial changes.
2024-04-30 Added a link to Network Interface Statistics.
2023-09-14 Added a link to TLS For Accessory Developers.
2023-07-23 First posted.
Hi, I am making a AI-Powered app that makes api requests to the openai API. However, for security, I set up a vercel backend that handles the API calls securely, while my frontend makes a call to my vercel-hosted https endpoint. Interestingly, whenever I try to make that call on my device, an iPhone, I get this error:
Task <91AE4DE0-2845-4348-89B4-D3DD1CF51B65>.<10> finished with error [-1003] Error Domain=NSURLErrorDomain Code=-1003 "A server with the specified hostname could not be found." UserInfo={_kCFStreamErrorCodeKey=-72000, NSUnderlyingError=0x1435783f0 {Error Domain=kCFErrorDomainCFNetwork Code=-1003 "(null)" UserInfo={_kCFStreamErrorDomainKey=10, _kCFStreamErrorCodeKey=-72000, _NSURLErrorNWResolutionReportKey=Resolved 0 endpoints in 3ms using unknown from query, _NSURLErrorNWPathKey=satisfied (Path is satisfied), interface: pdp_ip0[lte], ipv4, ipv6, dns, expensive, uses cell}}, _NSURLErrorFailingURLSessionTaskErrorKey=LocalDataTask <91AE4DE0-2845-4348-89B4-D3DD1CF51B65>.<10>, _NSURLErrorRelatedURLSessionTaskErrorKey=(
"LocalDataTask <91AE4DE0-2845-4348-89B4-D3DD1CF51B65>.<10>"
), NSLocalizedDescription=A server with the specified hostname could not be found., NSErrorFailingURLStringKey=https://[my endpoint], NSErrorFailingURLKey=https://[my endpoint], _kCFStreamErrorDomainKey=10}
I'm completely stuck because when I directly make https requests to other api's like openai's endpoint, without the proxy, it finds the server completely fine. Running my endpoint on terminal with curl also works as intended, as I see api key usages. But for some reason, on my project, it does not work. I've looked through almost every single post I could find online, but a lot all of the solutions are outdated and unhelpful.
I'm willing to schedule a call, meeting, whatever to resolve this issue and get help more in depth as well.
Hello,
I'm running into an issue while developing an iOS app that requires local network access. I’m using the latest MacBook Air M4 with macOS sequoia 15.5 and Xcode 16.1. In the iOS Simulator, my app fails to discover devices connected to the same local network.
I’ve already added the necessary key to the Info.plist:
NSLocalNetworkUsageDescription
This app needs access to local network devices.
When I run the app on a real device and M2 Chip Macbook's simulators, it works fine for local network permission as expected. However, in the M4 Chip Macbook's Simulator:
The app can’t find any devices on the local network
Bonjour/mDNS seems not to be working as well
I’ve tried the following without success:
Restarting Simulator and Mac
Resetting network settings in Simulator
Confirming app permissions under System Settings > Privacy & Security
Has anyone else encountered this issue with the new Xcode/macOS combo? Is local network access just broken in the Simulator for now, or is there a workaround?
Thanks in advance!
Hello everyone,
I'm trying to figure out how to transmit a UIImage (png or tiff) securely to an application running in my desktop browser (Mac or PC). The desktop application and iOS app would potentially be running on the same local network (iOS hotspot or something) or have no internet connection at all.
I'm trying to securely send over an image that the running desktop app could ingest. I was thinking something like a local server securely accepting image data from an iPhone.
Any suggestions ideas or where to look for more info would be greatly appreciated!
Thank you for your help.
I'm using NERelayManager to set Relay configuration which all works perfectly fine.
I then do a curl with the included domain and while I see QUIC connection succeeds with relay server and H3 request goes to the server, the connection gets abruptly closed by the client with "Software caused connection abort".
Console has this information:
default 09:43:04.459517-0700 curl nw_flow_connected [C1.1.1 192.168.4.197:4433 in_progress socket-flow (satisfied (Path is satisfied), viable, interface: en0[802.11], ipv4, ipv6, dns, uses wifi)] Transport protocol connected (quic)
default 09:43:04.459901-0700 curl [C1.1.1 192.168.4.197:4433 in_progress socket-flow (satisfied (Path is satisfied), viable, interface: en0[802.11], ipv4, ipv6, dns, uses wifi)] event: flow:finish_transport @0.131s
default 09:43:04.460745-0700 curl nw_flow_connected [C1.1.1 192.168.4.197:4433 in_progress socket-flow (satisfied (Path is satisfied), viable, interface: en0[802.11], ipv4, ipv6, dns, uses wifi)] Joined protocol connected (http3)
default 09:43:04.461049-0700 curl [C1.1.1 192.168.4.197:4433 in_progress socket-flow (satisfied (Path is satisfied), viable, interface: en0[802.11], ipv4, ipv6, dns, uses wifi)] event: flow:finish_transport @0.133s
default 09:43:04.465115-0700 curl [C2 E47A3A0C-7275-4F6B-AEDF-59077ABAE34B 192.168.4.197:4433 quic, multipath service: 1, tls, definite, attribution: developer] cancel
default 09:43:04.465238-0700 curl [C2 E47A3A0C-7275-4F6B-AEDF-59077ABAE34B 192.168.4.197:4433 quic, multipath service: 1, tls, definite, attribution: developer] cancelled
[C2 FCB1CFD1-4BF9-4E37-810E-81265D141087 192.168.4.139:53898<->192.168.4.197:4433]
Connected Path: satisfied (Path is satisfied), viable, interface: en0[802.11], ipv4, ipv6, dns, uses wifi
Duration: 0.121s, QUIC @0.000s took 0.000s, TLS 1.3 took 0.111s
bytes in/out: 2880/4322, packets in/out: 4/8, rtt: 0.074s, retransmitted bytes: 0, out-of-order bytes: 0
ecn packets sent/acked/marked/lost: 3/1/0/0
default 09:43:04.465975-0700 curl nw_flow_disconnected [C2 192.168.4.197:4433 cancelled multipath-socket-flow ((null))] Output protocol disconnected
default 09:43:04.469189-0700 curl nw_endpoint_proxy_receive_report [C1.1 IPv4#124bdc4d:80 in_progress proxy (satisfied (Path is satisfied), interface: en0[802.11], ipv4, ipv6, dns, proxy, uses wifi)] Privacy proxy failed with error 53 ([C1.1.1] masque Proxy: http://192.168.4.197:4433)
default 09:43:04.469289-0700 curl [C1.1.1 192.168.4.197:4433 failed socket-flow (satisfied (Path is satisfied), viable, interface: en0[802.11], ipv4, ipv6, dns, uses wifi)] event: flow:failed_connect @0.141s, error Software caused connection abort
Relay server otherwise works fine with our QUIC MASQUE clients but not with built-in macOS MASQUE client. Anything I'm missing?
Hi there, I am working on an app that configures a PacketTunnelProvider to establish a VPN connection. Unfortunately, while a VPN connection is established, I am unable to update the app via testflight. Downloading other app updates works fine.
I noticed that after I receive the alert that updating failed, the vpn badge appears at the top of my screen (the same ux that occurs when the connection is first established). So it's almost like it tried to close the tunnel, and seeing that the app update failed it restablishes the tunnel.
I am unsure of why I would not be able to update my app. Maybe stopTunnel is not being called with NEProviderStopReason.appUpdate?
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.
multicast sockets fail to send/receive on macosx, errno 65 "no route to host".
Wireshark and Terminal.app (which have root privileges) both show incoming multicast traffic just fine.
Normal UDP broadcast sockets have no problems.
Toggling the Security&Privacy -> Local Network setting may fix the problem for some Users.
There is no pattern for when multicast socket fails.
Sometimes, recreating the sockets fix the problem.
Restart the app, sometimes multicast fails, sometimes success (intermittent, no pattern).
Reboot machine (intermittent fail)
Create a fresh new user on machine, install single version of app, give app permission. (intermittent fail, same as above).
We have all the normal entitlements / notarized app.
Similar posts here
see FB16923535, Related to FB16512666
https://forum.xojo.com/t/udp-multicast-receive-on-mac-failing-intermittant/83221
see my post from 2012 "distinguishing between SENDING sockets and RECEIVING sockets" for source code example of how we bind multicast sockets. Our other socket code is standard "Stevens, et al." code. The bind() is the call that fails in this case. https://stackoverflow.com/questions/10692956/what-does-it-mean-to-bind-a-multicast-udp-socket . Note that this post from 2012 is still relevant, and that it is a workaround to a longstanding Apple bug that was never fixed. Namely, "Without this fix, multicast sending will intermittently get sendto() errno 'No route to host'. If anyone can shed light on why unplugging a DHCP gateway causes Mac OS X multicast SENDING sockets to get confused, I would love to hear it."
This may be a hint as to the underlying bug that Apple really needs to fix, but if it's not, then please Apple, fix the Sequoia bug first. These are probably different bugs because in one case, sendto() fails when a socket becomes "unbound" after you unplug an unrelated network cable. In this case, bind() fails, so sendto() is never even called.
Note, that we have also tried to use other implementations for network discovery, including Bonjour, CFNetwork, etc. Bonjour fails intermittently, and also suffers from both bugs mentioned above, amongst others.
hello
I am testing the use of network extension. When we use dnsproxy to proxy DNS requests,
we will send you a message that the udp pcbcount of your system continues to increase.
For example
for ((i=1; i<=99999; i++));do
echo "Attempt $i:"
dig google.com
done
when the dig command is used continuously,
the dig command will show the following errors when pcbcount reaches a certain number.
isc_socket_bind: address not available
Can you help us determine what the problem might be? thank you
I'm a long-time developer, but pretty new to Swift. I'm trying to get information from a web service (and found code online that I adjusted to build the function below). (Note: AAA_Result -- referenced towards the end -- is another class in my project)
Trouble is, I'm getting the subject error on the call to session.dataTask. Any help/suggestions/doc pointers will be greatly appreciated!!!
var result: Bool = false
var cancellable: AnyCancellable?
self.name = name
let params = "json={\"\"}}" // removed json details
let base_url = URL(string: "https://aaa.yyy.com?params=\(params)&format=json")! // removed URL specifics
do {
let task = URLSession.shared.dataTask(with: base_url) { data, response, error in
if let error = error {
print("Error: \(error)")
}
guard let response = response as? HTTPURLResponse, (200...299).contains(response.statusCode)
else {
print("Error \(String(describing: response))")
}
do {
let decoder = JSONDecoder()
let ar = try decoder.decode(AAA_Result.self, from: response.value)
// removed specific details...
result = true
}
catch {
print(error)
}
}
task.resume()
}
catch {
print(error)
}
return result
}
Topic:
App & System Services
SubTopic:
Networking
Are the network relays introduced in 2023 and
https://developer.apple.com/videos/play/wwdc2023/10002/
the same thing as the Private Relay introduced in 2021?
https://developer.apple.com/videos/play/wwdc2021/10096/
We are considering verifying the relay function, but we are not sure whether they are the same function or different functions.
https://developer.apple.com/documentation/devicemanagement/relay?language=objc
Topic:
App & System Services
SubTopic:
Networking
Every now and again folks notice that Network framework seems to create an unexpected number of connections on the wire. This post explains why that happens and what you should do about it.
If you have questions or comments, put them in a new thread here on the forums. Use the App & System Services > Networking topic area and the Network tag.
Share and Enjoy
—
Quinn “The Eskimo!” @ Developer Technical Support @ Apple
let myEmail = "eskimo" + "1" + "@" + "apple.com"
Understanding Also-Ran Connections
Network framework implements the Happy Eyeballs algorithm. That might create more on-the-wire connections than you expect. There are two common places where folks notice this:
When looking at a packet trace
When implementing a listener
Imagine that you’ve implemented a TCP server using NWListener and you connect to it from a client using NWConnection. In many situations there are multiple network paths between the client and the server. For example, on a local network there’s always at least two paths: the link-local IPv6 path and either an infrastructure IPv4 path or the link-local IPv4 path.
When you start your NWConnection, Network framework’s Happy Eyeballs algorithm might [1] start a TCP connection for each of these paths. It then races those connections. The one that connects first is the ‘winner’, and Network framework uses that connection for your traffic. Once it has a winner, the other connections, the also-ran connections, are redundant, and Network framework just closes them.
You can observe this behaviour on the client side by looking in the system log. Many Network framework log entries (subsystem com.apple.network) contain a connection identifier. For example C8 is the eighth connection started by this process. Each connection may have child connections (C8.1, C8.2, …) and grandchild connections (C8.1.1, C8.1.2, …), and so on. You’ll see state transitions for these child connections occurring in parallel. For example, the following log entries show that C8 is racing the connection of two grandchild connections, C8.1.1 and C8.1.2:
type: debug
time: 12:22:26.825331+0100
process: TestAlsoRanConnections
subsystem: com.apple.network
category: connection
message: nw_socket_connect [C8.1.1:1] Calling connectx(…)
type: debug
time: 12:22:26.964150+0100
process: TestAlsoRanConnections
subsystem: com.apple.network
category: connection
message: nw_socket_connect [C8.1.2:1] Calling connectx(…)
Note For more information about accessing the system log, see Your Friend the System Log.
You also see this on the server side, but in this case each connection is visible to your code. When you connect from the client, Network framework calls your listener’s new connection handler with multiple connections. One of those is the winning connection and you’ll receive traffic on it. The others are the also-ran connections, and they close promptly.
IMPORTANT Depending on network conditions there may be no also-ran connections. Or there may be lots of them. If you want to test the also-ran connection case, use Network Link Conditioner to add a bunch of delay to your packets.
You don’t need to write special code to handle also-ran connections. From the perspective of your listener, these are simply connections that open and then immediately close. There’s no difference between an also-ran connection and, say, a connection from a client that immediately crashes. Or a connection generated by someone doing a port scan. Your server must be resilient to such things.
However, the presence of these also-ran connections can be confusing, especially if you’re just getting started with Network framework, and hence this post.
[1] This is “might” because the exact behaviour depends on network conditions. More on that below.
Hi Team,
I have a Network Extension application and UI frontend for it.
The UI frontend talks to the Network Extension using XPC, as provided by NEMachServiceName.
On M2 machine,
The application and XPC connection works fine on clean installation.
But, when the application is upgraded, the XPC connection keeps failing.
Upgrade steps:
PreInstall script kills the running processes, both UI and Network Extension
Let installation continue
PostInstall script to launch the application after installation complete.
Following code is successful to the point of resume from UI application
NSXPCInterface *exportedInterface = [NSXPCInterface interfaceWithProtocol:@protocol(IPCUIObject)];
newConnection.exportedInterface = exportedInterface;
newConnection.exportedObject = delegate;
NSXPCInterface *remoteObjectInterface = [NSXPCInterface interfaceWithProtocol:@protocol(IPCExtObject)];
newConnection.remoteObjectInterface = remoteObjectInterface;
self.currentConnection = newConnection;
[newConnection resume];
But it fails to get the object
id<IPCExtObject> providerProxy = [self.currentConnection remoteObjectProxyWithErrorHandler:^(NSError *registerError) {
}];
Please note, this only fails for M2. For M1, this exact code is running fine.
Additionally, if I uninstall the application by dropping it in Trash and then installing the newer version, then too, the application works fine.