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MacOS input buffer size over 1020 bytes
Hello Currently, we are developing an application that collects measurement data from devices via USB port but we have some problems regarding input buffer size that might reduce the reading speed. The data size is quite big (~1.5 million bytes). For every read action, the app will check the available size in the input buffer by command: ioctl(serialPort.hHandle, FIONREAD, readBuffSize) Then that size will be passed as the desired size for the read command. Between read actions, there will be a short sleep (1 - 3 ms). Please confirm some points below: Regardless of the size of the measure data, the available size will only be up to 1020 bytes, is it expected? Is the above size OS defined or driver defined? Could we increase it? As we checked, there were some missing bytes between the measure data and the actual read data. Is there any chance that the data in the input buffer be overwritten while the read thread is in sleep? Any recommended technique that can increase reading speed while still maintaining the integrity of the data? Tested OS: Sonoma 14.5
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447
Nov ’24
Update 18.0 to 18.1 CarPlay
Since updating to 18.0 & 18.1 I’ve have issues with CarPlay connected via usb, phone calls specifically where people would say I sound distant and robotic distortion. Tried other vehicles same issue new usb same issue, tried all recommendations with no success some one who refused to update theirs worked well without any issues I’m currently facing. Any suggestions or there gonna be an update that addresses this issue ?
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377
Nov ’24
InputStream and OutputStream from EASession is not ready for use if accessory was connected when app is not launched
Hi everyone. I have an iOS application for work with an MFi-certified device connected to the iPhone via USB-C. When I launch the app and attach the device, I can create an EASession and use the InputStream and OutputStream as usual. But if I attach the device before launching the app I can't use the InputStream and OutputStream, because the hasBytesAvailable and hasSpaceAvailable properties are always false. The NSStreamEventHasBytesAvailable and NSStreamEventHasSpaceAvailable events will never be triggered. After I re-attach the device, the streams open fine and I can interact with the device. What can be wrong with the case of attaching the device before the app launches?
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492
Oct ’24
Peripheral Devices control on macOS
We are looking for a solution (API, Frameworks) that would allow us to block any type of external device, including storage devices, HIDs, network adapters, and Bluetooth devices according with dynamic rules that comes from management server . This feature is important for endpoint security solutions vendors, and it can be implemented on other platforms and older versions of macOS using the IOKit framework and kexts. I have found one solution that can control the usage only of "storage" devices with the EndpointSecurity framework in conjunction with the DiskArbitration framework. This involves monitoring the MOUNT and OPEN events for /dev/disk files, checking for devices as they appear, and ejecting them if they need to be blocked.. Also, I have found the ES_EVENT_TYPE_AUTH_IOKIT_OPEN event in EndpointSecurity.framework, but it doesn't seem to be useful, at least not for my purposes, because ES doesn't provide AUTH events for some system daemons, such as configd (it only provides NOTIFY events). Furthermore, there are other ways to communicate with devices and their drivers apart from IOKit. DriverKit.framework does not provide the necessary functionality either, as it requires specific entitlements that are only available to certain vendors and devices. Therefore, it cannot be used to create universal drivers for all devices, which should be blocked. Any advice would be greatly appreciated!
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505
Oct ’24
How to enable PCIDriverKit Bus Leader? (and Memory Space enable?)
I am porting a working kernel extension IOKit driver to a DriverKit system extension. Our device is a PCI device accessed through Thunderbolt. The change from IOPCIFamily to PCIDriverKit has some differences in approach, though. Namely, in IOKit / IOPCIFamily, this was the correct way to become Bus Leader: mPCIDevice->setBusLeadEnable(true); // setBusMasterEnable(..) deprecated in OS 12.4 but now, PCIDriverKit's IOPCIDevice does not have that function. Instead I am doing the following: // Set Bus Leader and Memory Space enable uint16_t commandRegister = 0; ivars->mPCIDevice->ConfigurationRead16(kIOPCIConfigurationOffsetCommand, &commandRegister); commandRegister |= (kIOPCICommandBusLead | kIOPCICommandMemorySpace); ivars->mPCIDevice->ConfigurationWrite16(kIOPCIConfigurationOffsetCommand, commandRegister); But I am not convinced this is working (I am still experiencing unexpected errors when attempting to DMA from our device, using the same steps that work for the kernel extension). The only hint I can find in the online documentation is here, which reads: Note The endpoint driver is responsible for enabling the Memory Space Enable and Bus Master Enable settings each time it configures the PCI device. When a crash occurs, or when the system unloads your driver, the system disables these features. ...but that does not state directly how to enable bus leader status. What is the "PCIDriverKit approved" way to become bus leader? Is there a way to verify/confirm that a device is bus leader? (This would be helpful to prove that bus leadership is not the issue for DMA errors, as well as to confirm that bus leadership was granted). Thanks in advance!
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599
Sep ’24
Proper way to use IOKit in iOS app?
Hello, forum, I'm trying to build connection between a non-MFi HID device (like keyboard) and iOS app with IOKit and Swift. Thanks to this post, I have manage to import the IOKit into objc header. IOKit on iOS/iPadOS 16.0+ #import <IOKit/IOKitLib.h> However, I have this compiler error when I try to imitate same methods in the SerialPortSaple project from following article, but the IOKit can not be imported to Swift at first place. Communicating with a Modem on a Serial Port The screen shot of the sample project: It looks like the complier unable to reach the io_object_t type somehow, is there any workaround or approach?
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1.6k
Jun ’24
How to open "Driver Extensions" on macOS 15 by using objective-C
Hello everybody, Since macOS 15, the systemextension allow in changed as switch style and put in the "Login items & Extensions". I know the URL navigating to here, which is: x-apple.systempreferences:com.apple.LoginItems-Settings.extension But the extension options we need to scroll deep down and we need to click the "!" to open it. I want to open the finally window for user can easily see it and enable it. Please tell me how. Appreciate!!
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897
Oct ’24
AU Plugin Not Connecting to DriverKit Driver in Sandboxed Host
Hello, I'm developing a custom AU plugin that needs to connect to a DriverKit driver. Using the DriverKit sample (https://github.com/DanBurkhardt/DriverKitUserClientSample.git), I was able to get a standalone app to connect to the driver successfully. However, the AU plugin, running in a sandboxed host, isn't establishing the connection. I’ve already added the app sandbox entitlement, but it hasn’t helped. Any advice on what might be missing? TIA!
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502
Oct ’24
IOServiceNameMatching can't find dext service
I'm using the following code to find the dext service. The driver is enabled in iOS settings prior to launching the app. io_service_t mService = IO_OBJECT_NULL; kern_return_t ret = kIOReturnSuccess; io_iterator_t iterator = IO_OBJECT_NULL; if (__builtin_available(iOS 15.0, *)) { ret = IOServiceGetMatchingServices(kIOMainPortDefault, IOServiceNameMatching("MyDriver"), &iterator); } else { // Fallback on earlier versions } if (ret != kIOReturnSuccess) { printf("Unable to find service"); } while ((mService = IOIteratorNext(iterator)) != IO_OBJECT_NULL) { //Only able to find service if launching the app first and then connecting the device .......... } I noticed the call IOServiceNameMatching doesn't return the same result for the following workflows: Launch the app first and then connect the device, IOServiceGetMatchingServices can find the service. Connect the device to USB-C port first, then launch the app, the same call can't find a matching service (iterator is null). I would need to disconnect and reconnect the device while the app is running in order to find the matching dext. Any suggestion on how to find the matching dext service for workflow #2? Thanks
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775
Aug ’24
USBDriverKit driver not showing up in settings on iPadOS 18
In iPadOS 17.7 my driver shows up in settings just fine. After recompiling with Xcode 16 and installing my app (containing my driver) on iPadOS 18, the app shows up in settings but the driver-enable button is missing from Settings. When I plug-in my custom USB device, the app cannot detect it and I am left with no way to manually enable the driver, as I did in the previous version of iPadOS.
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595
Sep ’24
DriverKit driver doesn't appear in Settings when installed with iPad app
I'm working on a DriverKit driver. I have it running on macOS, including a very simple client app written in SwiftUI. Everything is working fine there. I've added iPadOS as a destination for the app as demonstrated in the WWDC video on DriverKit for iPadOS. The app builds and runs on my iPad, as expected (after a little work to conditionalize out my use of SystemExtensions.framework for installation on macOS). However, after installing and running the app on an iPad, the driver does not show up in Settings->General, nor in the app-specific settings pane triggered by the inclusion of a settings bundle in the app. I've confirmed that the dext is indeed being included in the app bundle when built for iPadOS (in MyApp.app/SystemExtensions/com.me.MyApp.MyDriver.dext). I also can see in the build log that there's a validation step for the dext, and that seems to be succeeding. I don't know why the app isn't being discovered -- or in any case surfaced to the user -- when the app is installed on the iPad. Has anyone faced this problem and solved it? Are there ways to troubleshoot installation/discovery of an embedded DriverKit extensions on iOS? Unlike on macOS, I don't really see any relevant console messages.
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1.8k
Feb ’23
Unable to Print or Scan to/from HP Pagewide Pro 477dw MFP
Upgraded my 2 machines to Sequoia 15 and consequently I am unable to print or scan with both machines. A 3rd machine which is not upgraded as yet is unaffected. AirPrint from iPhones is not affected. The printing process executes without error. The printer receives the job but does not actually execute the print. The machine behaves like the job in the queue is completed normally. No error message. Just no physical printout. Happens with all applications. When Scanning - fails to connect to device to enable scanning. error message after some time is attached
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343
Sep ’24
Access Bluetooth in system daemon - Unauthorized
Hello, as the title says, I am trying to access Bluetooth in a system daemon. I am running on MacOS Sonoma 14.5. When initializing Bluetooth, my daemon received Unauthorized state. I have tried to add my daemon in the system settings (System Preferences > Security & Privacy > Privacy > Bluetooth) "Allow applications to access Bluetooth" by adding the program executable path defined by the entry Program of my system daemon as suggested here: https://developer.apple.com/forums/thread/662459. But I am still having the issue. Writing a system daemon with Bluetooth is not my final goal. The bigger picture is the smartcard reader driver with Bluetooth access which as the same issue and the solution is probably related. I do not remember how but my smartcard reader driver use to work with Bluetooth but it does now with the same Unauthorized error. As far as I can see daemon and smartcard drivers does not have support for entitlement. Here are the logs for my sample system daemon: my_daemon [0x6000011b0000] activating connection: mach=true listener=false peer=false name=com.apple.server.bluetooth.le.att.xpc bluetoothd [0x7f804828e8a0] activating connection: mach=false listener=false peer=true name=com.apple.server.bluetooth.le.att.xpc.peer[76672].0x7f804828e8a0 bluetoothd Received XPC message "CBMsgIdCheckIn" from session "" bluetoothd Received XPC check-in from session "my_daemon-5555494498236e3b5e2e395b93c13af176769937-peripheral-76672-67" fAccessLevel 0 fProgrammaticPairing 0 fLimitedForMediaAccess 0 bluetoothd Access level is less than kXPCAccessLevelSystem for session "my_daemon-5555494498236e3b5e2e395b93c13af176769937-peripheral-76672-67". Restricted state operation not allowed bluetoothd Sending 'session attached' event for session "my_daemon-5555494498236e3b5e2e395b93c13af176769937-peripheral-76672-67" bluetoothd Attached session for "my_daemon-5555494498236e3b5e2e395b93c13af176769937-peripheral-76672-67" with session: 0x7f804802d1b0, session handle: 0xef8d0000 bluetoothd Registering peripheral session "my_daemon-5555494498236e3b5e2e395b93c13af176769937-peripheral-76672-67" with backgrounding: off, persistence: off (CBSR) restoreID: (null) bluetoothd Error getting Application State for <private>: <private>, 3 bluetoothd Error getting Application State for <private>: <private>, 3 bluetoothd Session "my_daemon-5555494498236e3b5e2e395b93c13af176769937-peripheral-76672-67" tccRequired : 1 bluetoothd ReadyForTCC. TCC required:1 fLimitedForMediaAccess:0 fDeviceAccessForMediaExtension:0 bluetoothd Session "my_daemon-5555494498236e3b5e2e395b93c13af176769937-peripheral-76672-67" : needsRestrictedStateOperation = 0, overrideRestrictedState = 0 , denylistMode = 0, receivesControllerBTClockEvents=0 my_daemon Received CBMsgIdReadyForTCC my_daemon Running performTccCheck CBManager tccAvail 1, tccRequired 1 my_daemon TCC required my_daemon [0x6000011b8000] activating connection: mach=true listener=false peer=false name=com.apple.tccd my_daemon [0x6000011b8000] failed to do a bootstrap look-up: xpc_error=[3: No such process] my_daemon [0x6000011b8000] invalidated after a failed init my_daemon send_message_with_reply(): user tccd unavailable, sending 0x600000ab4000 to system tccd my_daemon [0x6000011b4000] activating connection: mach=true listener=false peer=false name=com.apple.tccd.system tccd [0x7fd4d1f7ed80] activating connection: mach=false listener=false peer=true name=com.apple.tccd.system.peer[76672].0x7fd4d1f7ed80 tccd REQUEST: tccd_uid=0, sender_pid=76672, sender_uid=0, sender_auid=-1, function=TCCAccessRequest, msgID=76672.1 tccd AUTHREQ_CTX: msgID=76672.1, function=<private>, service=kTCCServiceBluetoothAlways, preflight=no, query=1, client_dict=(null), daemon_dict=<private> tccd AUTHREQ_ATTRIBUTION: msgID=76672.1, attribution={requesting={TCCDProcess: identifier=my_daemon-5555494498236e3b5e2e395b93c13af176769937, pid=76672, auid=0, euid=0, binary_path=/Users/olivier/daemon/my_daemon}, }, tccd AUTHREQ_SUBJECT: msgID=76672.1, subject=/Users/olivier/daemon/my_daemon, tccd Refusing TCCAccessRequest for service kTCCServiceBluetoothAlways from client Sub:{/Users/olivier/daemon/my_daemon}Resp:{TCCDProcess: identifier=my_daemon-5555494498236e3b5e2e395b93c13af176769937, pid=76672, auid=0, euid=0, binary_path=/Users/olivier/daemon/my_daemon} in background session tccd AUTHREQ_RESULT: msgID=76672.1, authValue=0, authReason=5, authVersion=1, error=(null), tccd REPLY: (0) function=TCCAccessRequest, msgID=76672.1 my_daemon [0x6000011b4000] invalidated after the last release of the connection object bluetoothd Received XPC message "CBMsgIdTCCDone" from session "my_daemon-5555494498236e3b5e2e395b93c13af176769937-peripheral-76672-67" tccd [0x7fd4d1f7ed80] invalidated after getting a no-senders notification - client is gone bluetoothd [0x7f80482820f0] activating connection: mach=true listener=false peer=false name=com.apple.tccd.system tccd [0x7fd4d32585f0] activating connection: mach=false listener=false peer=true name=com.apple.tccd.system.peer[169].0x7fd4d32585f0 tccd REQUEST: tccd_uid=0, sender_pid=169, sender_uid=0, sender_auid=-1, function=TCCAccessRequest, msgID=169.48 tccd [0x7fd4d313d880] activating connection: mach=true listener=false peer=false name=com.apple.tccd tccd [0x7fd4d313d880] failed to do a bootstrap look-up: xpc_error=[3: No such process] bluetoothd [0x7f80482820f0] invalidated after the last release of the connection object bluetoothd Bluetooth user permission alwaysAuth: denied tccd [0x7fd4d313d880] invalidated after a failed init tccd FORWARD: to=com.apple.tccd/0, request: { require_purpose=<xpc_null> service="kTCCServiceBluetoothAlways" function="TCCAccessRequest" preflight=true target_token={pid:76672, auid:-1, euid:0} TCCD_MSG_ID="169.48" background_session=false } tccd REPLY: from=com.apple.tccd, reply: { XPCErrorDescription="Connection invalid" } tccd forwardMessage error: Connection invalid. tccd [0x7fd4d3152bf0] activating connection: mach=false listener=false peer=true name=com.apple.tccd.system.peer[169].0x7fd4d3152bf0 bluetoothd [0x7f80482820f0] activating connection: mach=true listener=false peer=false name=com.apple.tccd.system tccd REQUEST: tccd_uid=0, sender_pid=169, sender_uid=0, sender_auid=-1, function=TCCAccessRequest, msgID=169.49 tccd [0x7fd4d32585f0] invalidated after getting a no-senders notification - client is gone tccd [0x7fd4d1f4c810] activating connection: mach=true listener=false peer=false name=com.apple.tccd tccd [0x7fd4d1f4c810] failed to do a bootstrap look-up: xpc_error=[3: No such process] tccd [0x7fd4d1f4c810] invalidated after a failed init tccd FORWARD: to=com.apple.tccd/0, request: { require_purpose=<xpc_null> service="kTCCServiceBluetoothAlways" function="TCCAccessRequest" preflight=true target_token={pid:76672, auid:-1, euid:0} TCCD_MSG_ID="169.49" background_session=false } tccd REPLY: from=com.apple.tccd, reply: { XPCErrorDescription="Connection invalid" } tccd forwardMessage error: Connection invalid.
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948
Jun ’24
How to Symbolicate an Apple Silicon Panic?
Investigating a kernel panic, I discovered that Apple Silicon Panic traces are not working with how I know to symbolicate the panic information. I have not found proper documentation that corrects this situation. Attached file is an indentity-removed panic, received from causing an intentional panic (dereferencing nullptr), so that I know what functions to expect in the call stack. This is cut-and-pasted from the "Report To Apple" dialog that appears after the reboot: panic_1_4_21_b.txt To start, I download and install the matching KDK (in this case KDK_14.6.1_23G93.kdk), identified from this line: OS version: 23G93 Kernel version: Darwin Kernel Version 23.6.0: Mon Jul 29 21:14:04 PDT 2024; root:xnu-10063.141.2~1/RELEASE_ARM64_T8122 Then start lldb from Terminal, using this command: bash_prompt % lldb -arch arm64e /Library/Developer/KDKs/KDK_14.6.1_23G93.kdk/System/Library/Kernels/kernel.release.t8122 Next I load the remaining scripts per the instructions from lldb: (lldb) settings set target.load-script-from-symbol-file true I need to know what address to load my kext symbols to, which I read from this line of the panic log, after the @ symbol: com.company.product(1.4.21d119)[92BABD94-80A4-3F6D-857A-3240E4DA8009]@0xfffffe001203bfd0->0xfffffe00120533ab I am using a debug build of my kext, so the DWARF symbols are part of the binary. I use this line to load the symbols into the lldb session: (lldb) addkext -F /Library/Extensions/KextName.kext/Contents/MacOS/KextName 0xfffffe001203bfd0 And now I should be able to use lldb image lookup to identify pointers on the stack that land within my kext. For example, the current PC at the moment of the crash lands within the kext (expected, because it was intentional): (lldb) image lookup -a 0xfffffe001203fe10 Which gives the following incorrect result: Address: KextName[0x0000000000003e40] (KextName.__TEXT.__cstring + 14456) Summary: "ffer has %d retains\n" That's not even a program instruction - that's within a cstring. No, that cstring isn't involved in anything pertaining to the intentional panic I am expecting to see. Can someone please explain what I'm doing wrong and provide instructions that will give symbol information from a panic trace on an Apple Silicon Mac? Disclaimers: Yes I know IOPCIFamily is deprecated, I am in process of transitioning to DriverKit Dext from IOKit kext. Until then I must maintain the kext. Terminal command "atos" provides similar incorrect results, and seems to not work with debug-built-binaries (only dSYM files) Yes this is an intentional panic so that I can verify the symbolicate process before I move on to investigating an unexpected panic I have set nvram boot-args to include keepsyms=1 I have tried (lldb) command script import lldb.macosx but get a result of error: no images in crash log (after the nvram settings)
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1.3k
Aug ’24