Hello @all I'm develop a DriverKit driver extension and without entitlement checks by OS everything runs fine. But if the entitlements check is enabled in the NVRAM then I get an error due connecting my IOUserClient instance. Which entitlements are really and exactly required for my driver? My driver contains: one IOUserClient instance and multiple IOUserSerial instances The bundle identifier of the driver ist: org.eof.tools.VSPDriver The bundle identifier of the client app org.eof.tools.VSPInstall My entire source code is available on GitHub if any one want to dive deep in :) kernel[0:5107] () [VSPDriver]: NewUserClient called. kernel[0:5107] () [VSPDriver]: CreateUserClient: create VSP user client from Info.plist. kernel[0:5107] () [VSPUserClient]: init called. kernel[0:5107] () [VSPUserClient]: init finished. kernel[0:5107] () [VSPDriver]: CreateUserClient: check VSPUserClient type. kernel[0:5107] () [VSPDriver]: CreateUserClient: success. kernel[0:5107] () [VSPDriver]: NewUserClient finished. kernel[0:5107] () [VSPUserClient]: Start: called. kernel[0:5107] () [VSPUserClient]: User client successfully started. kernel[0:389f] DK: VSPUserClient-0x100001127:UC failed userclient-access check, needed bundle ID org.eof.tools.VSPDriver kernel[0:389f] DK: VSPUserClient-0x100001127:UC entitlements check failed kernel[0:5107] () [VSPUserClient]: Stop called. kernel[0:5107] () [VSPUserClient]: User client successfully removed. kernel[0:5107] () [VSPUserClient]: free called. Here my drivers entitlement file: <?xml version="1.0" encoding="UTF-8"?> <!DOCTYPE plist PUBLIC "-//Apple//DTD PLIST 1.0//EN" "http://www.apple.com/DTDs/PropertyList-1.0.dtd"> <plist version="1.0"> <dict> <key>com.apple.developer.driverkit</key> <true/> <key>com.apple.developer.driverkit.allow-third-party-userclients</key> <true/> <key>com.apple.developer.driverkit.family.serial</key> <true/> </dict> </plist> Here my drivers Info.plist file <?xml version="1.0" encoding="UTF-8"?> <!DOCTYPE plist PUBLIC "-//Apple//DTD PLIST 1.0//EN" "http://www.apple.com/DTDs/PropertyList-1.0.dtd"> <plist version="1.0"> <dict> <key>CFBundleDevelopmentRegion</key> <string>$(DEVELOPMENT_LANGUAGE)</string> <key>CFBundleExecutable</key> <string>$(EXECUTABLE_NAME)</string> <key>CFBundleIdentifier</key> <string>$(PRODUCT_BUNDLE_IDENTIFIER)</string> <key>CFBundleInfoDictionaryVersion</key> <string>6.0</string> <key>CFBundleName</key> <string>$(PRODUCT_NAME)</string> <key>CFBundlePackageType</key> <string>$(PRODUCT_BUNDLE_PACKAGE_TYPE)</string> <key>CFBundleShortVersionString</key> <string>1.0</string> <key>CFBundleVersion</key> <string>1</string> <key>NSHumanReadableCopyright</key> <string>Copyright © 2025 by EoF Software Labs</string> <key>OSBundleUsageDescription</key> <string>Provide virtual serial port</string> <key>com.apple.developer.driverkit</key> <true/> <key>com.apple.developer.driverkit.allow-any-userclient-access</key> <true/> <key>com.apple.developer.driverkit.communicates-with-drivers</key> <true/> <key>com.apple.developer.system-extension.redistributable</key> <true/> <key>OSBundleLibraries</key> <dict> <key>com.apple.iokit.IOSerialFamily</key> <string>1.0</string> </dict> <key>IOKitPersonalities</key> <dict> <key>VSPDriver</key> <dict> <key>CFBundleIdentifier</key> <string>$(PRODUCT_BUNDLE_IDENTIFIER)</string> <key>CFBundleIdentifierKernel</key> <string>com.apple.kpi.iokit</string> <key>IOMatchCategory</key> <string>$(PRODUCT_BUNDLE_IDENTIFIER)</string> <key>IOProviderClass</key> <string>IOUserResources</string> <key>IOResourceMatch</key> <string>IOKit</string> <key>IOProbeScore</key> <integer>0</integer> <key>IOClass</key> <string>IOUserService</string> <key>IOUserClass</key> <string>VSPDriver</string> <key>IOUserServerName</key> <string>$(PRODUCT_BUNDLE_IDENTIFIER)</string> <key>UserClientProperties</key> <dict> <key>IOClass</key> <string>IOUserUserClient</string> <key>IOUserClass</key> <string>VSPUserClient</string> </dict> <key>SerialPortProperties</key> <dict> <key>CFBundleIdentifierKernel</key> <string>com.apple.driver.driverkit.serial</string> <key>IOProviderClass</key> <string>IOSerialStreamSync</string> <key>IOClass</key> <string>IOUserSerial</string> <key>IOUserClass</key> <string>VSPSerialPort</string> <key>HiddenPort</key> <false/> <key>IOTTYBaseName</key> <string>vsp</string> <key>IOTTYSuffix</key> <string>0</string> </dict> </dict> </dict> </dict> </plist> Here the entitlements of the client app <?xml version="1.0" encoding="UTF-8"?> <!DOCTYPE plist PUBLIC "-//Apple//DTD PLIST 1.0//EN" "http://www.apple.com/DTDs/PropertyList-1.0.dtd"> <plist version="1.0"> <dict> <key>com.apple.developer.driverkit</key> <true/> <key>com.apple.developer.driverkit.allow-third-party-userclients</key> <true/> <key>com.apple.developer.driverkit.communicates-with-drivers</key> <true/> <key>com.apple.developer.shared-with-you</key> <true/> <key>com.apple.developer.system-extension.install</key> <true/> <key>com.apple.security.application-groups</key> <array> <string>$(TeamIdentifierPrefix).org.eof.apps</string> </array> </dict> </plist> Here the Info.plist of the client app: <?xml version="1.0" encoding="UTF-8"?> <!DOCTYPE plist PUBLIC "-//Apple//DTD PLIST 1.0//EN" "http://www.apple.com/DTDs/PropertyList-1.0.dtd"> <plist version="1.0"> <dict> <key>CFBundleDevelopmentRegion</key> <string>$(DEVELOPMENT_LANGUAGE)</string> <key>CFBundleExecutable</key> <string>$(EXECUTABLE_NAME)</string> <key>CFBundleIdentifier</key> <string>$(PRODUCT_BUNDLE_IDENTIFIER)</string> <key>CFBundleInfoDictionaryVersion</key> <string>6.0</string> <key>CFBundleName</key> <string>$(PRODUCT_NAME)</string> <key>CFBundlePackageType</key> <string>$(PRODUCT_BUNDLE_PACKAGE_TYPE)</string> <key>CFBundleShortVersionString</key> <string>1.0</string> <key>CFBundleVersion</key> <string>1</string> <key>LSMinimumSystemVersion</key> <string>$(MACOSX_DEPLOYMENT_TARGET)</string> <key>com.apple.developer.driverkit</key> <true/> <key>com.apple.developer.driverkit.install</key> <true/> <key>com.apple.developer.system-extension.install</key> <true/> <key>com.apple.developer.system-extension.uninstall</key> <true/> <key>com.apple.developer.driverkit.userclient-access</key> <array> <string>VSPDriver</string> </array> <key>com.apple.private.driverkit.driver-access</key> <array> <string>VSPDriver</string> </array> <key>com.apple.security.temporary-exception.iokit-user-client-class</key> <array> <string>IOUserUserClient</string> </array> </dict> </plist>

Kevin's Guide to DEXT Signing The question of "How do I sign a DEXT" comes up a lot, so this post is my attempt to describe both what the issues are and the best current solutions are. So... The Problems: When DEXTs were originally introduced, the recommended development signing process required disabling SIP and local signing. There is a newer, much simpler process that's built on Xcode's integrated code-signing support; however, that newer process has not yet been integrated into the documentation library. In addition, while the older flow still works, many of the details it describes are no longer correct due to changes to Xcode and the developer portal. DriverKit's use of individually customized entitlements is different than the other entitlements on our platform, and Xcode's support for it is somewhat incomplete and buggy. The situation has improved considerably over time, particularly from Xcode 15 and Xcode 16, but there are still issues that are not fully resolved. To address #1, we introduced "development" entitlement variants of all DriverKit entitlements. These entitlement variants are ONLY available in development-signed builds, but they're available on all paid developer accounts without any special approval. They also allow a DEXT to match against any hardware, greatly simplifying working with development or prototype hardware which may not match the configuration of a final product. Unfortunately, this also means that DEXT developers will always have at least two entitlement variants (the public development variant and the "private" approved entitlement), which is what then causes the problem I mentioned in #2. The Automatic Solution: If you're using Xcode 16 or above, then Xcode's Automatic code sign support will work all DEXT Families, with the exception of distribution signing the PCI and USB Families. For completeness, here is how that Automatic flow should work: Change the code signing configuration to "Automatic". Add the capability using Xcode. (USB & PCI) Edit your Entitlement.plist to include the correct "Development Only" configuration: USB Development Only Configuration: <key>com.apple.developer.driverkit.transport.usb</key> <array> <dict> <key>idVendor</key> <string>*</string> </dict> </array> PCI Development Only Configuration: <key>com.apple.developer.driverkit.transport.pci</key> <array> <dict> <key>IOPCIPrimaryMatch</key> <string>0xFFFFFFFF&amp;0x00000000</string> </dict> </array> If you've been approved for one of these entitlements, the one oddity you'll see is that adding your approved capability will add both the approved AND the development variant, while deleting either will delete both. This is a visual side effect of #2 above; however, aside from the exception described below, it can be ignored. Similarly, you can sign distribution builds by creating a build archive and then exporting the build using the standard Xcode flow. Debugging Automatic Code-signing In a new project, the flow I describe above should just work; however, if you're converting an existing project, you may get code signing errors, generally complaining about how the provisioning profile configuration doesn't match. In most cases, this happens because Xcode is choosing to reuse a previously downloaded profile with an older configuration instead of generating a new configuration which would then include the configuration changes you made. Currently, you can find these profile files in: ~/Library/Developer/Xcode/UserData/Provisioning Profiles ...which can make it easier to find and delete the specific profile (if you choose). However, one recommendation I'd have here is to not treat the contents of that folder as "precious" or special. What automatic code signing actually does is generate provisioning profiles "on demand", so if you delete an automatic profile... Xcode will just generate it again at the next build. Manually generating profiles is more cumbersome, but the solution there is to preserve them as a separate resource, probably as part of your project data, NOT to just "lose" them in the folder here. If they get deleted from Xcode's store, then you can just copy them back in from your own store (or using Xcode, which can manually download profiles as well). The advantage of this approach is that when profiles "pile up" over time (which they tend to do), you can just delete[1] all of them then let Xcode regenerate the ones you're actually trying to investigate. In terms of looking at their contents, TN3125: Inside Code Signing: Provisioning Profiles has the details of how to see exactly what's there. [1] Moving them somewhere else works too, but could indicate a fear of commitment. __ Kevin Elliott DTS Engineer, CoreOS/Hardware

Note: This document is specifically focused on what happens after a DEXT has passed its initial code-signing checks. Code-signing issues are dealt with in other posts. Preliminary Guidance: Using and understanding DriverKit basically requires understanding IOKit, something which isn't entirely clear in our documentation. The good news here is that IOKit actually does have fairly good "foundational" documentation in the documentation archive. Here are a few of the documents I'd take a look at: IOKit Fundamentals IOKit Device Driver Design Guidelines Accessing Hardware From Applications Special mention to QA1075: "Making sense of IOKit error codes",, which I happened to notice today and which documents the IOReturn error format (which is a bit weird on first review). Those documents do not cover the full DEXT loading process, but they are the foundation of how all of this actually works. Understanding the IOKitPersonalities Dictionary The first thing to understand here is that the "IOKitPersonalities" is called that because it is in fact a fully valid "IOKitPersonalities" dictionary. That is, what the system actually uses that dictionary "for" is: Perform a standard IOKit match and load cycle in the kernel. The final driver in the kernel then uses the DEXT-specific data to launch and run your DEXT process outside the kernel. So, working through the critical keys in that dictionary: "IOProviderClass"-> This is the in-kernel class that your in-kernel driver loads "on top" of. The IOKit documentation and naming convention uses the term "Nub", but the naming convention is not consistent enough that it applies to all cases. "IOClass"-> This is the in-kernel class that your DEXT attaches to and works through. This is where things can become a bit confused, as some families work by: Routing all activity through the provider reference so that the DEXT-specific class does not matter (PCIDriverKit). Having the DEXT subclass a specific subclass which corresponds to a specific kernel driver (SCSIPeripheralsDriverKit). This distinction is described in the documentation, but it's easy to overlook if you don't understand what's going on. However, compare PCIDriverKit: "When the system loads your custom PCI driver, it passes an IOPCIDevice object as the provider to your driver. Use that object to read and write the configuration and memory of your PCI hardware." Versus SCSIPeripheralsDriverKit: Develop your driver by subclassing IOUserSCSIPeripheralDeviceType00 or IOUserSCSIPeripheralDeviceType05, depending on whether your device works with SCSI Block Commands (SBC) or SCSI Multimedia Commands (SMC), respectively. In your subclass, override all methods the framework declares as pure virtual. The reason these differences exist actually comes from the relationship and interactions between the DEXT families. Case in point, PCIDriverKit doesn't require a specific subclass because it wants SCSIControllerDriverKit DEXTs to be able to directly load "above" it. Note that the common mistake many developers make is leaving "IOUserService" in place when they should have specified a family-specific subclass (case 2 above). This is an undocumented implementation detail, but if there is a mismatch between your DEXT driver ("IOUserSCSIPeripheralDeviceType00") and your kernel driver ("IOUserService"), you end up trying to call unimplemented kernel methods. When a method is "missing" like that, the codegen system ends up handling that by returning kIOReturnUnsupported. One special case here is the "IOUserResources" provider. This class is the DEXT equivalent of "IOResources" in the kernel. In both cases, these classes exist as an attachment point for objects which don't otherwise have a provider. It's specifically used by the sample "Communicating between a DriverKit extension and a client app" to allow that sample to load on all hardware but is not something the vast majority of DEXT will use. Following on from that point, most DEXT should NOT include "IOMatchCategory". Quoting IOKit fundamentals: "Important: Any driver that declares IOResources as the value of its IOProviderClass key must also include in its personality the IOMatchCategory key and a private match category value. This prevents the driver from matching exclusively on the IOResources nub and thereby preventing other drivers from matching on it. It also prevents the driver from having to compete with all other drivers that need to match on IOResources. The value of the IOMatchCategory property should be identical to the value of the driver's IOClass property, which is the driver’s class name in reverse-DNS notation with underbars instead of dots, such as com_MyCompany_driver_MyDriver." The critical point here is that including IOMatchCategory does this: "This prevents the driver from matching exclusively on the IOResources nub and thereby preventing other drivers from matching on it." The problem here is that this is actually the exceptional case. For a typical DEXT, including IOMatchCategory means that a system driver will load "beside" their DEXT, then open the provider blocking DEXT access and breaking the DEXT. DEXT Launching The key point here is that the entire process above is the standard IOKit loading process used by all KEXT. Once that process finishes, what actually happens next is the DEXT-specific part of this process: IOUserServerName-> This key is the bundle ID of your DEXT, which the system uses to find your DEXT target. IOUserClass-> This is the name of the class the system instantiates after launching your DEXT. Note that this directly mimics how IOKit loading works. Keep in mind that the second, DEXT-specific, half of this process is the first point your actual code becomes relevant. Any issue before that point will ONLY be visible through kernel logging or possibly the IORegistry. __ Kevin Elliott DTS Engineer, CoreOS/Hardware

Hello everyone, We are in the process of migrating a high-performance storage KEXT to DriverKit. During our initial validation phase, we noticed a performance gap between the DEXT and the KEXT, which prompted us to try and optimize our I/O handling process. Background and Motivation: Our test hardware is a RAID 0 array of two HDDs. According to AJA System Test, our legacy KEXT achieves a write speed of about 645 MB/s on this hardware, whereas the new DEXT reaches about 565 MB/s. We suspect the primary reason for this performance gap might be that the DEXT, by default, uses a serial work-loop to submit I/O commands, which fails to fully leverage the parallelism of the hardware array. Therefore, to eliminate this bottleneck and improve performance, we configured a dedicated parallel dispatch queue (MyParallelIOQueue) for the UserProcessParallelTask method. However, during our implementation attempt, we encountered a critical issue that caused a system-wide crash. The Operation Causing the Panic: We configured MyParallelIOQueue using the following combination of methods: In the .iig file: We appended the QUEUENAME(MyParallelIOQueue) macro after the override keyword of the UserProcessParallelTask method declaration. In the .cpp file: We manually created a queue with the same name by calling the IODispatchQueue::Create() function within our UserInitializeController method. The Result: This results in a macOS kernel panic during the DEXT loading process, forcing the user to perform a hard reboot. After the reboot, checking with the systemextensionsctl list command reveals the DEXT's status as [activated waiting for user], which indicates that it encountered an unrecoverable, fatal error during its initialization. Key Code Snippets to Reproduce the Panic: In .iig file - this was our exact implementation: class DRV_MAIN_CLASS_NAME: public IOUserSCSIParallelInterfaceController { public: virtual kern_return_t UserProcessParallelTask(...) override QUEUENAME(MyParallelIOQueue); }; In .h file: struct DRV_MAIN_CLASS_NAME_IVars { // ... IODispatchQueue* MyParallelIOQueue; }; In UserInitializeController implementation: kern_return_t IMPL(DRV_MAIN_CLASS_NAME, UserInitializeController) { // ... // We also included code to manually create the queue. kern_return_t ret = IODispatchQueue::Create("MyParallelIOQueue", kIODispatchQueueReentrant, 0, &ivars->MyParallelIOQueue); if (ret != kIOReturnSuccess) { // ... error handling ... } // ... return kIOReturnSuccess; } Our Question: What is the officially recommended and most stable method for configuring UserProcessParallelTask_Impl() to use a parallel I/O queue? Clarifying this is crucial for all developers pursuing high-performance storage solutions with DriverKit. Any explanation or guidance would be greatly appreciated. Best Regards, Charles

I have a DriverKit system extension (dext) that uses PCIDriverKit. I would like to get the build environment straightened out to successfully distribute the dext and associated software to end users. There are three types of software involved: The Dext-hosting application - this is the application that must be installed to /Applications/, and will perform the registration of the dext. The dext is deployed "within" this application, and can be found in the /Contents/Library/SystemExtensions folder of the app bundle. The dext itself - this is the actual binary system extension, which will be registered by its owning application, and will operate in its own application space independent of the hosting application. Additional applications that communicate with the dext - these are applications which will connect to the dext through user clients, but these applications do not contain the dext themselves. There are multiple locations where settings need to be exactly correct for each type of software to be signed, provisioned, and notarized properly in order to be distributed to users: developer.apple.com - where "identifiers" and "provisioning profiles" are managed. Note that there are differences in access between "Team Agent", "Admin", and "Developer" at this site. Xcode project's Target "Signing & Capabilities" tab - this is where "automatically manage signing" can be selected, as well as team selection, provisioning profile selection, and capabilities can be modified. Xcode project's Target "Build Settings" tab - this is where code signing identity, code signing development team, code signing entitlements file selection, Info.plist options and file selection, and provisioning profile selection. Xcode's Organizer window, which is where you manage archives and select for distribution. In this case, I am interested in "Developer ID" Direct Distribution - I want the software signed with our company's credentials (Team Developer ID) so that users know they can trust the software. Choosing "automatically manage signing" does not work for deployment. The debug versions of software include DriverKit (development) capability (under App ID configuration at developer.apple.com), and this apparently must not be present in distributable provisioning. I believe this means that different provisioning needs to occur between debug and release builds? I have tried many iterations of selections at all the locations, for all three types of binaries, and rather than post everything that does not work, I am asking, "what is supposed to work?"

Hello everyone. After a lot of research and some tests from various sources, I have actually built a small SerialDriverKit IOUserSerial driver. Unfortunately, the documentation on the official sites is tight-lipped and very thin. At least I have a running driver instance. Now my request and question: Can anyone give me a tip on how to get the data from the serial client? I have already called IOUserSerial::ConnectQueues(...) in the IOUserSerial::Start() method and I got the IOMemoryDescriptors for interrupt, RX and TX to my driver instance. I tried to get access to the memory in the method IOUserSerial::TxDataAvailable() with IOMemoryDescriptor::CreateMapping(...). Unfortunately, no data is coming in. It's always 0x00. Here is the OS log: kernel: (org.eof.tools.VSPDriver.dext) kernel: (org.eof.tools.VSPDriver.dext) [VSPDriver] init called. kernel: (org.eof.tools.VSPDriver.dext) [VSPDriverPrivate] constructor called. kernel: (org.eof.tools.VSPDriver.dext) [VSPDriver] start called. kernel: (org.eof.tools.VSPDriver.dext) IOUserSerial::: 40 0x600000da4058 kernel: (org.eof.tools.VSPDriver.dext) [VSPDriverPrivate] Start called. kernel: (org.eof.tools.VSPDriver.dext) [VSPDriverPrivate] Connect INT/RX/TX buffer. kernel: (org.eof.tools.VSPDriver.dext) IOUserSerial::: 59 0x600000da4058 kernel: (org.eof.tools.VSPDriver.dext) [VSPDriverPrivate] prepare TCP socket. kernel: (org.eof.tools.VSPDriver.dext) [VSPDriver] driver started successfully. kernel: DK: VSPDriver-0x100000753::start(IOUserResources-0x100000116) ok ... ... some client serial setup stuff ... kernel: (IOUserSerial) IOUserSerial::hwResetFIFO: 1076 ==&gt;0 kernel: (IOUserSerial) IOUserSerial::hwResetFIFO: 1076 &lt;== kernel: (IOUserSerial) IOUserSerial::hwResetFIFO: 1076 locklevel = 1 kernel: (org.eof.tools.VSPDriver.dext) [VSPDriver] HwResetFIFO called. kernel: (org.eof.tools.VSPDriver.dext) [VSPDriverPrivate] HwResetFIFO called. kernel: (org.eof.tools.VSPDriver.dext) [VSPDriverPrivate] HwResetFIFO: tx=0 rx=1 kernel: (IOUserSerial) IOUserSerial::hwResetFIFO: 1076 ==&gt;0 kernel: (org.eof.tools.VSPDriver.dext) [VSPDriver] TxDataAvailable called. kernel: (org.eof.tools.VSPDriver.dext) [VSPDriverPrivate] TxDataAvailable called. kernel: (org.eof.tools.VSPDriver.dext) [VSPDriverPrivate] TxDataAvailable: address=0x104c22000 length=16384 kernel: (org.eof.tools.VSPDriver.dext) [VSPDriverPrivate] TxDataAvailable: debug TX buffer kernel: (org.eof.tools.VSPDriver.dext) [VSPDriverPrivate] TxDataAvailable: TX&gt; 0x00 kernel: (org.eof.tools.VSPDriver.dext) [VSPDriverPrivate] TxDataAvailable: TX&gt; 0x00 kernel: (org.eof.tools.VSPDriver.dext) [VSPDriverPrivate] TxDataAvailable: TX&gt; 0x00 kernel: (org.eof.tools.VSPDriver.dext) [VSPDriverPrivate] TxDataAvailable: TX&gt; 0x00 kernel: (org.eof.tools.VSPDriver.dext) [VSPDriverPrivate] TxDataAvailable: TX&gt; 0x00 kernel: (org.eof.tools.VSPDriver.dext) [VSPDriverPrivate] TxDataAvailable: TX&gt; 0x00 kernel: (org.eof.tools.VSPDriver.dext) [VSPDriverPrivate] TxDataAvailable: TX&gt; 0x00 kernel: (org.eof.tools.VSPDriver.dext) [VSPDriverPrivate] TxDataAvailable: TX&gt; 0x00 kernel: (org.eof.tools.VSPDriver.dext) [VSPDriverPrivate] TxDataAvailable: TX&gt; 0x00 kernel: (org.eof.tools.VSPDriver.dext) [VSPDriverPrivate] TxDataAvailable: TX&gt; 0x00 kernel: (org.eof.tools.VSPDriver.dext) [VSPDriverPrivate] TxDataAvailable: TX&gt; 0x00 kernel: (org.eof.tools.VSPDriver.dext) [VSPDriverPrivate] TxDataAvailable: TX&gt; 0x00 kernel: (org.eof.tools.VSPDriver.dext) [VSPDriverPrivate] TxDataAvailable: TX&gt; 0x00 kernel: (org.eof.tools.VSPDriver.dext) [VSPDriverPrivate] TxDataAvailable: TX&gt; 0x00 kernel: (org.eof.tools.VSPDriver.dext) [VSPDriverPrivate] TxDataAvailable: TX&gt; 0x00 kernel: (org.eof.tools.VSPDriver.dext) [VSPDriverPrivate] TxDataAvailable: TX&gt; 0x00

I'm having trouble configuring the "IOPCIPrimaryMatch" entitlement. I'm currently developing using "sign to run locally" and have been able to confirm the expected behavior. I was considering signing with "Developer ID Application" for future distribution to customers, but after finding the following forum, I'm now aiming to sign with "Apple Development." https://developer.apple.com/forums/thread/743021 I'm currently having trouble with the IOPCIPrimaryMatch value. The "signing certificate" status in Xcode changes depending on the value, as follows: Successful if the value is as follows: IOPCIPrimaryMatch 0xFFFFFFFF&0x00161916 An error occurs if the value is as follows: IOPCIPrimaryMatch 0xFFFFFFFF&0x00161916 So I tried building and installing using "0xFFFFFFFF&0x00161916", but this time the driver was not assigned to the PCI device. By the way, when I used "sign to run locally", both the installation and assignment were successful with the following: IOPCIPrimaryMatch 0xFFFFFFFF&0x00161916 Could you please tell me the correct way to write this?

Hi all, We are migrating a SCSI HBA driver from KEXT to DriverKit (DEXT), with our DEXT inheriting from IOUserSCSIParallelInterfaceController. We've encountered a data corruption issue that is reliably reproducible under specific conditions and are hoping for some assistance from the community. Hardware and Driver Configuration: Controller: LSI 3108 DEXT Configuration: We are reporting our hardware limitations to the framework via the UserReportHBAConstraints function, with the following key settings: // UserReportHBAConstraints... addConstraint(kIOMaximumSegmentAddressableBitCountKey, 0x20); // 32-bit addConstraint(kIOMaximumSegmentCountWriteKey, 129); addConstraint(kIOMaximumByteCountWriteKey, 0x80000); // 512KB Observed Behavior: Direct I/O vs. Buffered I/O We've observed that the I/O behavior differs drastically depending on whether it goes through the system file cache: 1. Direct I/O (Bypassing System Cache) -> 100% Successful When we use fio with the direct=1 flag, our read/write and data verification tests pass perfectly for all file sizes, including 20GB+. 2. Buffered I/O (Using System Cache) -> 100% Failure at >128MB Whether we use the standard cp command or fio with the direct=1 option removed to simulate buffered I/O, we observe the exact same, clear failure threshold: Test Results: File sizes ≤ 128MB: Success. Data checksums match perfectly. File sizes ≥ 256MB: Failure. Checksums do not match, and the destination file is corrupted. Evidence of failure reproduced with fio (buffered_integrity_test.fio, with direct=1 removed): fio --size=128M buffered_integrity_test.fio -> Test Succeeded (err=0). fio --size=256M buffered_integrity_test.fio -> Test Failed (err=92), reporting the following error, which proves a data mismatch during the verification phase: verify: bad header ... at file ... offset 1048576, length 1048576 fio: ... error=Illegal byte sequence Our Analysis and Hypothesis The phenomenon of "Direct I/O succeeding while Buffered I/O fails" suggests the problem may be related to the cache synchronization mechanism at the end of the I/O process: Our UserProcessParallelTask_Impl function correctly handles READ and WRITE commands. When cp or fio (buffered) runs, the WRITE commands are successfully written to the LSI 3108 controller's onboard DRAM cache, and success is reported up the stack. At the end of the operation, to ensure data is flushed to disk, the macOS file system issues an fsync, which is ultimately translated into a SYNCHRONIZE CACHE SCSI command (Opcode 0x35 or 0x91) and sent to our UserProcessParallelTask_Impl. We hypothesize that our code may not be correctly identifying or handling this SYNCHRONIZE CACHE opcode. It might be reporting "success" up the stack without actually commanding the hardware to flush its cache to the physical disk. The OS receives this "success" status and assumes the operation is safely complete. In reality, however, the last batch of data remains only in the controller's volatile DRAM cache and is eventually lost. This results in an incomplete or incorrect file tail, and while the file size may be correct, the data checksum will inevitably fail. Summary Our DEXT driver performs correctly when handling Direct I/O but consistently fails with data corruption when handling Buffered I/O for files larger than 128MB. We can reliably reproduce this issue using fio with the direct=1 option removed. The root cause is very likely the improper handling of the SYNCHRONIZE CACHE command within our UserProcessParallelTask. P.S. This issue did not exist in the original KEXT version of the driver. We would appreciate any advice or guidance on this issue. Thank you.

Hello everyone, We are migrating our KEXT for a Thunderbolt storage device to a DEXT based on IOUserSCSIParallelInterfaceController. We've run into a fundamental issue where the driver's behavior splits based on the I/O source: high-level I/O from the file system (e.g., Finder, cp) is mostly functional (with a minor ls -al sorting issue for Traditional Chinese filenames), while low-level I/O directly to the block device (e.g., diskutil) fails or acts unreliably. Basic read/write with dd appears to be mostly functional. We suspect that our DEXT is failing to correctly register its full device "personality" with the I/O Kit framework, unlike its KEXT counterpart. As a result, low-level I/O requests with special attributes (like cache synchronization) sent by diskutil are not being handled correctly by the IOUserSCSIParallelInterfaceController framework of our DEXT. Actions Performed & Relevant Logs 1. Discrepancy: diskutil info Shows Different Device Identities for DEXT vs. KEXT For the exact same hardware, the KEXT and DEXT are identified by the system as two different protocols. KEXT Environment: Device Identifier: disk5 Protocol: Fibre Channel Interface ... Disk Size: 66.0 TB Device Block Size: 512 Bytes DEXT Environment: Device Identifier: disk5 Protocol: SCSI SCSI Domain ID: 2 SCSI Target ID: 0 ... Disk Size: 66.0 TB Device Block Size: 512 Bytes 2. Divergent I/O Behavior: Partial Success with Finder/cp vs. Failure with diskutil High-Level I/O (Partially Successful): In the DEXT environment, if we operate on an existing volume (e.g., /Volumes/MyVolume), file copy operations using Finder or cp succeed. Furthermore, the logs we've placed in our single I/O entry point, UserProcessParallelTask_Impl, are triggered. Side Effect: However, running ls -al on such a volume shows an incorrect sorting order for files with Traditional Chinese names (they appear before . and ..). Low-Level I/O (Contradictory Behavior): In the DEXT environment, when we operate directly on the raw block device (/dev/disk5): diskutil partitionDisk ... -> Fails 100% of the time with the error: Error: -69825: Wiping volume data to prevent future accidental probing failed. dd command -> Basic read/write operations appear to work correctly (a write can be immediately followed by a read within the same DEXT session, and the data is correct). 3. Evidence of Cache Synchronization Failure (Non-deterministic Behavior) The success of the dd command is not deterministic. Cross-environment tests prove that its write operations are unreliable: First Test: In the DEXT environment, write a file with random data to /dev/disk5 using dd. Reboot into the KEXT environment. Read the data back from /dev/disk5 using dd. The result is a file filled with all zeros. Conclusion: The write operation only went to the hardware cache, and the data was lost upon reboot. Second Test: In the DEXT environment, write the same random file to /dev/disk5 using dd. Key Variable: Immediately after, still within the DEXT environment, read the data back once for verification. The content is correct! Reboot into the KEXT environment. Read the data back from /dev/disk5. This time, the content is correct! Conclusion: The additional read operation in the second test unintentionally triggered a hardware cache flush. This proves that the dd (in our DEXT) write operation by itself does not guarantee synchronization, making its behavior unreliable. Our Problem Based on the observations above, we have the conclusion: High-Level Path (triggered by Finder/cp): When an I/O request originates from the high-level file system, the framework seems to enter a fully-featured mode. In this mode, all SCSI commands, including READ/WRITE, INQUIRY, and SYNCHRONIZE CACHE, are correctly packaged and dispatched to our UserProcessParallelTask_Impl entry point. Therefore, Finder operations are mostly functional. Low-Level Path (triggered by dd/diskutil): When an I/O request originates from the low-level raw block device layer: The most basic READ/WRITE commands can be dispatched (which is why dd appears to work). However, critical management commands, such as INQUIRY and SYNCHRONIZE CACHE, are not being correctly dispatched or handled. This leads to the incorrect device identification in diskutil info and the failure of diskutil partitionDisk due to its inability to confirm cache synchronization. We would greatly appreciate any guidance, suggestions, or insights on how to resolve this discrepancy. Specifically, what is the recommended approach within DriverKit to ensure that a DEXT based on IOUserSCSIParallelInterfaceController can properly declare its capabilities and handle both high-level and low-level I/O requests uniformly? Thank you. Charles

Hello everyone, I am migrating a legacy KEXT to a DriverKit (DEXT) architecture. While the DEXT itself is working correctly, I am completely blocked by a code signing issue when trying to establish the UserClient connection from our SwiftUI management app. Project Goal & Status: Our DEXT (com.accusys.Acxxx.driver) activates successfully (systemextensionsctl list confirms [activated enabled]). The core functionality is working (diskutil list shows the corresponding disk device node). The Core Problem: The userclient-access Signing Error To allow the app to connect to the DEXT, the com.apple.developer.driverkit.userclient-access entitlement is required in the app's .entitlements file. However, as soon as this entitlement is added, the build fails. Both automatic and manual signing fail with the same error: `Provisioning profile ... doesn't match the entitlements file's value for the ... userclient-access entitlement.` This build failure prevents the generation of an .app bundle, making it impossible to inspect the final entitlements with codesign. What We've Confirmed: The necessary capabilities (like DriverKit Communicates with Drivers) are visible and enabled for our App ID on the developer portal. The issue persists on a clean system state and on the latest macOS Sequoia 15.7.1. Our Research and Hypothesis: We have reviewed the official documentation "Diagnosing issues with entitlements" (TN3125). According to the documentation, a "doesn't match" error implies a discrepancy between the entitlements file and the provisioning profile. Given that we have tried both automatic and manual profiles (after enabling the capability online), our hypothesis is that the provisioning profile generation process on Apple's backend is not correctly including the approved userclient-access entitlement into the profile file itself. The build fails because Xcode correctly detects this discrepancy. Our Questions: Did we misunderstand a step in the process, or is the issue not with the entitlement request at all? Alternatively, are there any other modifications we can make to successfully connect our App to the DEXT and trigger NewUserClient? Thank you for any guidance.

This is my first driver and I have had the devil of a time trying to find any information to help me with this. I beg help with this, since I cannot find any tutorials that will get me over this problem. I am attempting to write a bridging driver for an older UPS that only communicates via RPC-over-USB rather than the HID Power Device class the OS requires. I have written the basic framework for the driver (details below) and am calling OSSystemExtensionRequest.submitRequest with a request object created by OSSystemExtensionRequest.activationRequest, but the didFailWithError callback is called with OSSystemExtensionErrorDomain of a value of 9, which appears to be a general failure to activate the driver. I can find no other information on how to address this issue, but I presume the issue is one of entitlements in either the entitlements file or Info.plist. I will have more code-based details below. For testing context, I am testing this on a 2021 iMac (M1) running Sequoia 15.7, and this iMac is on MDM, specifically Jamf. I have disabled SIP and set systemextensionsctl developer on, per the instructions here, and I have compiled and am attempting to debug the app using xcode 26.2. The driver itself targets DriverKit 25, as 26 does not appear to be available in xcode despite hints on google that it's out. For the software, I have a two-target structure in my xcode project, the main Manager app, which is a swift-ui app that both handles installation/activation of the driver and (if that finally manages to work) handles communication from the driver via its UserClient, and the driver which compiles as a dext. Both apps compile and use automated signing attached to our Apple Development team. I won't delve into the Manager app much, as it runs even though activation fails, except to include its entitlements file in case it proves relevant <dict> <key>com.apple.developer.driverkit.communicates-with-drivers</key> <true/> <key>com.apple.developer.system-extension.install</key> <true/> <key>com.apple.security.app-sandbox</key> <true/> <key>com.apple.security.files.user-selected.read-only</key> <true/> </dict> and the relevant activation code: func request(_ request: OSSystemExtensionRequest, didFailWithError error: any Error) { // handling the error, which is always code value 9 } func activateDriver() { let request = OSSystemExtensionRequest.activationRequest(forExtensionWithIdentifier: "com.mycompany.driver.bundle.identifier", queue: .main) request.delegate = self OSSystemExtensionManager.shared.submitRequest(request) //... } And finally the Manager app has the following capabilities requested for its matching identifier in our Apple Developer Account: DriverKit Communicates with Drivers System Extension On the Driver side, I have two major pieces, the main driver class MyDriver, and UserClient class, StatusUserClient. MyDriver derives from IDriverKit/IOService.iig but (in case this is somehow important) does not have the same name as the project/target name MyBatteryDriver. StatusUserClient derives from DriverKit/IOUserClient.iig. I have os_log(OS_LOG_DEFAULT, "trace messages") code in every method of both classes, including the initializers and Start implementations, and the log entries never seem to show up in Console, so I presume that means the OS never tried to load the driver. Unless I'm looking in the wrong place? Because I don't think the driver code is the current issue, I won't go into it unless it becomes necessary. As I mentioned above, I think this is a code signing / entitlements issue, but I don't know how to resolve it. In our Apple Developer account, the Driver's matching identifier has the following capabilities requested: DriverKit (development) DriverKit Allow Any UserClient (development) DriverKit Family HID Device (development) -- NOTE: this is planned for future use, but not yet implemented by my driver code. Could that be part of the problem? DriverKit Transport HID (development) DriverKit USB Transport (development) DriverKit USB Transport - VendorID -- submitted, no response from Apple yet HID Virtual Device -- submitted, no response from Apple. yet. This is vestigial from an early plan to build the bridge via shared memory funneling to a virtual HID device. I think I've found a way to do it with one Service, but... not sure yet. Still, that's a problem for tomorrow. Apparently I've gone over the 7000 character maximum so I will add my entitlements and info.plist contents in a reply.

Hi, We’re developing a DriverKit extension for iPadOS. In local Debug and Release builds, everything works as expected, but the same build uploaded to TestFlight fails at IOServiceOpen with the following errors: -536870212 (0xE00002EC) kIOReturnUnsupported -536870201 (0xE00002F7) kIOReturnNotPermitted What we’ve verified so far App entitlements We checked our main app entitlements file, and it has the correct capabilities for the driverkit communication &lt;?xml version="1.0" encoding="UTF-8"?&gt; &lt;!DOCTYPE plist PUBLIC "-//Apple//DTD PLIST 1.0//EN" "http://www.apple.com/DTDs/PropertyList-1.0.dtd"&gt; &lt;plist version="1.0"&gt; &lt;dict&gt; &lt;key&gt;com.apple.developer.driverkit.communicates-with-drivers&lt;/key&gt; &lt;true/&gt; &lt;key&gt;com.apple.developer.driverkit.userclient-access&lt;/key&gt; &lt;array&gt; &lt;string&gt;abc.def.ABCDriver&lt;/string&gt; &lt;/array&gt; &lt;key&gt;com.apple.developer.system-extension.install&lt;/key&gt; &lt;true/&gt; &lt;key&gt;com.apple.security.app-sandbox&lt;/key&gt; &lt;true/&gt; &lt;key&gt;com.apple.security.device.usb&lt;/key&gt; &lt;true/&gt; &lt;key&gt;com.apple.security.files.user-selected.read-write&lt;/key&gt; &lt;true/&gt; &lt;/dict&gt; &lt;/plist&gt; we also checked the Provisioning profile (as shown on the portal) and the “Enabled Capabilities” seems to have the correct DriverKit Capabilities enabled. Enabled Capabilities Access Wi-Fi Information, DriverKit, DriverKit (development), DriverKit Communicates with Drivers, DriverKit USB Transport (development), DriverKit USB Transport - VendorID, DriverKit UserClient Access, iCloud, In-App Purchase, Sign In with Apple, System Extension When we download and inspect the provisioning profile as plain text, we notice that some expected DriverKit entitlements appear to be missing from the section. &lt;key&gt;Entitlements&lt;/key&gt; &lt;dict&gt; &lt;key&gt;beta-reports-active&lt;/key&gt; &lt;true/&gt; &lt;key&gt;com.apple.developer.networking.wifi-info&lt;/key&gt; &lt;true/&gt; &lt;key&gt;com.apple.developer.driverkit&lt;/key&gt; &lt;true/&gt; &lt;key&gt;com.apple.developer.driverkit.communicates-with-drivers&lt;/key&gt; &lt;true/&gt; &lt;key&gt;application-identifier&lt;/key&gt; &lt;string&gt;ABC123456.abc.def&lt;/string&gt; &lt;key&gt;keychain-access-groups&lt;/key&gt; &lt;array&gt; &lt;string&gt;ABC123456.*&lt;/string&gt; &lt;string&gt;com.apple.token&lt;/string&gt; &lt;/array&gt; &lt;key&gt;get-task-allow&lt;/key&gt; &lt;false/&gt; &lt;key&gt;com.apple.developer.team-identifier&lt;/key&gt; &lt;string&gt;ABC123456&lt;/string&gt; &lt;key&gt;com.apple.developer.ubiquity-kvstore-identifier&lt;/key&gt; &lt;string&gt;ABC123456.*&lt;/string&gt; &lt;key&gt;com.apple.developer.icloud-services&lt;/key&gt; &lt;string&gt;*&lt;/string&gt; &lt;key&gt;com.apple.developer.icloud-container-identifiers&lt;/key&gt; &lt;array&gt;&lt;/array&gt; &lt;key&gt;com.apple.developer.icloud-container-development-container-identifiers&lt;/key&gt; &lt;array&gt;&lt;/array&gt; &lt;key&gt;com.apple.developer.ubiquity-container-identifiers&lt;/key&gt; &lt;array&gt;&lt;/array&gt; &lt;key&gt;com.apple.developer.driverkit.transport.usb&lt;/key&gt; &lt;array&gt; &lt;dict&gt; &lt;key&gt;idVendor&lt;/key&gt; &lt;integer&gt;1234&lt;/integer&gt; &lt;/dict&gt; &lt;/array&gt; &lt;key&gt;com.apple.developer.applesignin&lt;/key&gt; &lt;array&gt; &lt;string&gt;Default&lt;/string&gt; &lt;/array&gt; &lt;/dict&gt; We have a couple of questions: Could the missing com.apple.developer.driverkit.userclient-access entitlement in the provisioning profile alone explain the kIOReturnUnsupported / kIOReturnNotPermitted failures from IOServiceOpen? Why do some DriverKit capabilities appear in the Apple Developer portal UI but vanish from the actual profile we download? Is there an extra step we’re overlooking when regenerating profiles after toggling those capabilities? Thanks

The device I am trying to develop a firmware updater for is an NVMe drive with a USB4 interface. It can connect in USB4 mode (tunneled NVMe), in USB 3 mode or in USB 2 mode. In USB 2 and USB 3 mode, the device descriptor shows one interface with two alternates. Alternate 0 uses the bulk-only protocol, with one IN and one OUT pipe. Alternate 1 uses the UAS protocol, with two IN and two OUT pipes. I use identical code in my driver to send custom CDBs. I can see using IORegistryExplorer that in USB 2 mode, macOS chooses alternate 0, the bulk-only protocol. My custom CDBs and their accompanying data pay loads are put on the bus, more or less as expected. In USB 3 mode, macOS chooses alternate 1, the UAS protocol. My custom CDB is put on the bus, but no payload data is transferred. Is this expected behavior? If so, is there a way to force the OS to choose alternate 0 even when on USB 3, perhaps with another dext? I'll file a bug about this when Feedback Assistant lets me.

Hi everyone, I was following the Video Modernize PCI and SCSI drivers with DriverKit and the Document to implement UserMapHBAData(), and here’s my current implementation: // kern_return_t DRV_MAIN_CLASS_NAME::UserMapHBAData_Impl(uint32_t *uniqueTaskID) kern_return_t IMPL(DRV_MAIN_CLASS_NAME, UserMapHBAData) { Log("UserMapHBAData() - Start"); // Define the vm_page_size explicitly const uint32_t vm_page_size = 4096; kern_return_t ret; IOBufferMemoryDescriptor *buffer = nullptr; IOMemoryMap *memMap = nullptr; void *taskData = nullptr; // Create a buffer for HBA-specific task data ret = IOBufferMemoryDescriptor::Create(kIOMemoryDirectionOutIn, ivars->fTaskDataSize, vm_page_size, &buffer); __Require((kIOReturnSuccess == ret), Exit); // Map memory to the driver extension's memory space ret = buffer->CreateMapping(0, 0, 0, 0, 0, &memMap); __Require((kIOReturnSuccess == ret), Exit); // Retrieve mapped memory address taskData = reinterpret_cast<void *>(memMap->GetAddress()); __Require(taskData, Exit); // WARNING: Potential leak of an object stored into 'buffer' // WARNING: Potential leak of an object stored into 'memMap' // Assign a unique task ID ivars->fTaskID++; // ERROR: No member named 'fTaskID' in 'DriverKitAcxxx_IVars' ivars->fTaskArray[ivars->fTaskID] = taskData; *uniqueTaskID = ivars->fTaskID; Log("UserMapHBAData() - End"); return kIOReturnSuccess; Exit: // Cleanup in case of failure if (memMap) { memMap->free(); // Correct method for releasing memory maps } if (buffer) { buffer->free(); // Correct method for releasing buffer memory } LogErr("ret = 0x%0x", ret); Log("UserMapHBAData() - End"); return ret; } For reference, in KEXT, memory allocation is typically done using: IOBufferMemoryDescriptor *buffer = IOBufferMemoryDescriptor::inTaskWithOptions( kernel_task, // Task in which memory is allocated kIODirectionOutIn, // Direction (read/write) 1024, // Size of the buffer in bytes 4); // Alignment requirements However, after installing the dext, macOS hangs, and I have to do a hardware reset. After rebooting, the sysctl list output shows: % sectl list 1 extension(s) --- com.apple.system_extension.driver_extension enabled active teamID bundleID (version) name [state] * - com.accusys.DriverKitAcxxx (5.0/11) com.accusys.DriverKitAcxxx [activated waiting for user] Questions: What could be causing macOS to halt? How should I approach debugging and resolving this issue? Looking forward to your insights, any suggestions would be greatly appreciated! Best regards, Charles

My application installs a system extension. When I try to remove the app from the Applications folder (cmd + backspace) I get an error message: "The operation can’t be completed right now because another operation is in progress, such as moving or copying an item or emptying the Bin." According to systemextensionsctl the extension state is "terminating for uninstall but still running". I can see an error in the console logs: kernelmanagerd Failed to terminate dext com.my.driver-dk, error: Kernel request failed: (os/kern) invalid address (1) sysextd a category delegate declined to terminate extension with identifier: com.my.driver-dk sysextd failed to terminate extension with identifier: com.my.driver-dk: Optional(Error Domain=kernelmanagerd.KMError Code=38 "(null)") Issue occurs with macOS 13 - works fine with macOS 12 and macOS 11 What is the problem here? Have there been any changes in macOS in that regard?

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.

Hello Everyone, I'm encountering an issue while setting up a timer event in DriverKit and would appreciate any guidance. Here's my current implementation: void DRV_MAIN_CLASS_NAME::SetupEventTimer() { // 1. Create dispatch queue kern_return_t ret = IODispatchQueue::Create("TimerQueue", 0, 0, &ivars->dispatchQueue); if (ret != kIOReturnSuccess) { LogErr("Failed to create dispatch queue: 0x%x", ret); return; } // 2. Create timer source ret = IOTimerDispatchSource::Create(ivars->dispatchQueue, &ivars->dispatchSource); if (ret != kIOReturnSuccess) { LogErr("Failed to create timer: 0x%x", ret); OSSafeReleaseNULL(ivars->dispatchQueue); return; } /*! * @brief Create an instance of OSAction. * @discussion Methods to allocate an OSAction instance are generated for each method defined in a class with * a TYPE attribute, so there should not be any need to directly call OSAction::Create(). * @param target OSObject to receive the callback. This object will be retained until the OSAction is * canceled or freed. * @param targetmsgid Generated message ID for the target method. * @param msgid Generated message ID for the method invoked by the receiver of the OSAction * to generate the callback. * @param referenceSize Size of additional state structure available to the creator of the OSAction * with GetReference. * @param action Created OSAction with +1 retain count to be released by the caller. * @return kIOReturnSuccess on success. See IOReturn.h for error codes. */ // 3: Create an OSAction for the TimerOccurred method // THIS IS WHERE I NEED HELP OSAction* timerAction = nullptr; ret = OSAction::Create(this, 0, 0, 0, &timerAction); if (ret != kIOReturnSuccess) { LogErr("Failed to create OSAction: 0x%x", ret); goto cleanup; } // 4. Set handler ret = ivars->dispatchSource->SetHandler(timerAction); if (ret != kIOReturnSuccess) { LogErr("Failed to set handler: 0x%x", ret); goto cleanup; } // 5. Schedule timer (1 second) uint64_t deadline = mach_absolute_time() + NSEC_PER_SEC; ivars->dispatchSource->WakeAtTime(0, deadline, 0); cleanup: if (ret != kIOReturnSuccess) { OSSafeReleaseNULL(timerAction); OSSafeReleaseNULL(ivars->dispatchSource); OSSafeReleaseNULL(ivars->dispatchQueue); } } Problem: The code runs but the OSAction callback binding seems incorrect (Step 3). According to the OSAction documentation, I need to use the TYPE macro to properly bind the callback method. But I try to use TYPE(DRV_MAIN_CLASS_NAME::TimerOccurred) kern_return_t TimerOccurred() LOCALONLY; TYPE(TimerOccurred) kern_return_t TimerOccurred() LOCALONLY; kern_return_t TimerOccurred() TYPE(DRV_MAIN_CLASS_NAME::TimerOccurred) LOCALONLY; All results in Out-of-line definition of 'TimerOccurred' does not match any declaration in 'DRV_MAIN_CLASS_NAME' Questions: What is the correct way to declare a timer callback method using TYPE? How to get the values targetmsgid & msgid generated by Xcode? Any help would be greatly appreciated! Best Regards, Charles

Hi there, We've discovered a problem with our iOS app. We've been attempting to add a Driverkit driver to it, but any time we run the app through Testflight, the driver installs fine, but when we go to enable the driver toggle in the app's settings, the toggle stays on, but in the device logs I can see: could not insert bundle at <private> into manager: <private> As you would expect - this means the driver is not actually enabled and does not respond to a device being connected to the iPad. This does not happen when building & running the app locally, nor does it happen when installing an Ad Hoc build. We also have a different app, not yet shipped. We are able to add the driver to that app without issue. It works after going through Testflight. What we have discovered now is that everything works fine even if we just create an entirely new app with it's own bundle IDs. I should point out that in all cases, we're keeping the capabilities the same for each of these apps/IDs - including the managed capabilities. The bundle IDs that have this problem are older (5 years old or more). It seems like any newer ID will work, but trying to add the driver (and the associated managed capabilities) to an older app/ID results in this vague error message, with no further details. If we inspect the resulting dexts, we can also see that the "Internal requirements code size" is different on the ones that fail. The failing ones have a size of 204 bytes, whereas the working ones all have a size of 220 bytes. Not sure if that's related but it's strikingly consistent. Does this mean there is an issue with older app IDs, and we need Apple to manually refresh them in some way before the driverkit capabilities will work after going through Testflight? We have two apps in this state, both are of the same vintage (~5 years+). We've been battling this issue for months on and off, so would appreciate some help.

Hi Apple, We are working on a general USB device management solution on macOS for enterprise security. Our goal is to enforce policy-based restrictions on USB devices, such as: For USB storage devices: block mount, read, or write access. For other peripherals (e.g., USB headsets or microphones, raspberry pi, etc): block usage entirely. We know in past, kernel extension would be the way to go, but as kext has been deprecated. And DriverKit is the new advertised framework. At first, DriverKit looked like the right direction. However, after reviewing the documentation more closely, we noticed that using DriverKit for USB requires specific entitlements: DriverKit USB Transport – VendorID DriverKit USB Transport – VendorID and ProductID This raises a challenge: if our solution is meant to cover all types of USB devices, we would theoretically need entitlements for every VendorID/ProductID in existence. My questions are: Is DriverKit actually the right framework for this kind of general-purpose USB device control? If not, what framework or mechanism should we be looking at for enforcing these kinds of policies? We also developed an Endpoint Security product, but so far we haven’t found a relevant Endpoint Security event type that would allow us to achieve this. Any guidance on the correct technical approach would be much appreciated. Thanks in advance for your help.

I am writing a DriverKit driver for the first that uses the USBSerialDriverKit. The driver its purpose is to expose the device as serial interface (/dev/cu.tetra-pei0 or something like this). My problem: I don't see any logs from that driver in the console and I tried like 40 different approaches and checked everything. The last message I see is that the driver get successfully added to the system it is in the list of active and enabled system driver extensions but when I plug the device in none of my logs appear and it doesn't show up in ioreg. So without my driver the target device looks like this: +-o TETRA PEI interface@02120000 <class IOUSBHostDevice, id 0x10000297d, registered, matched, active, busy 0 (13 ms), retain 30> | { | "sessionID" = 268696051410 | "USBSpeed" = 3 | "UsbLinkSpeed" = 480000000 | "idProduct" = 36886 | "iManufacturer" = 1 | "bDeviceClass" = 0 | "IOPowerManagement" = {"PowerOverrideOn"=Yes,"DevicePowerState"=2,"CurrentPowerState"=2,"CapabilityFlags"=32768,"MaxPowerState"=2,"DriverPowerState"=0} | "bcdDevice" = 9238 | "bMaxPacketSize0" = 64 | "iProduct" = 2 | "iSerialNumber" = 0 | "bNumConfigurations" = 1 | "UsbDeviceSignature" = <ad0c16901624000000ff0000> | "USB Product Name" = "TETRA PEI interface" | "locationID" = 34734080 | "bDeviceSubClass" = 0 | "bcdUSB" = 512 | "USB Address" = 6 | "kUSBCurrentConfiguration" = 1 | "IOCFPlugInTypes" = {"9dc7b780-9ec0-11d4-a54f-000a27052861"="IOUSBHostFamily.kext/Contents/PlugIns/IOUSBLib.bundle"} | "UsbPowerSinkAllocation" = 500 | "bDeviceProtocol" = 0 | "USBPortType" = 0 | "IOServiceDEXTEntitlements" = (("com.apple.developer.driverkit.transport.usb")) | "USB Vendor Name" = "Motorola Solutions, Inc." | "Device Speed" = 2 | "idVendor" = 3245 | "kUSBProductString" = "TETRA PEI interface" | "kUSBAddress" = 6 | "kUSBVendorString" = "Motorola Solutions, Inc." | } | +-o AppleUSBHostCompositeDevice <class AppleUSBHostCompositeDevice, id 0x100002982, !registered, !matched, active, busy 0, retain 5> | { | "IOProbeScore" = 50000 | "CFBundleIdentifier" = "com.apple.driver.usb.AppleUSBHostCompositeDevice" | "IOProviderClass" = "IOUSBHostDevice" | "IOClass" = "AppleUSBHostCompositeDevice" | "IOPersonalityPublisher" = "com.apple.driver.usb.AppleUSBHostCompositeDevice" | "bDeviceSubClass" = 0 | "CFBundleIdentifierKernel" = "com.apple.driver.usb.AppleUSBHostCompositeDevice" | "IOMatchedAtBoot" = Yes | "IOMatchCategory" = "IODefaultMatchCategory" | "IOPrimaryDriverTerminateOptions" = Yes | "bDeviceClass" = 0 | } | +-o lghub_agent <class AppleUSBHostDeviceUserClient, id 0x100002983, !registered, !matched, active, busy 0, retain 7> | { | "IOUserClientCreator" = "pid 1438, lghub_agent" | "IOUserClientDefaultLocking" = Yes | } | +-o IOUSBHostInterface@0 <class IOUSBHostInterface, id 0x100002986, registered, matched, active, busy 0 (5 ms), retain 9> | | { | | "USBPortType" = 0 | | "IOCFPlugInTypes" = {"2d9786c6-9ef3-11d4-ad51-000a27052861"="IOUSBHostFamily.kext/Contents/PlugIns/IOUSBLib.bundle"} | | "USB Vendor Name" = "Motorola Solutions, Inc." | | "bcdDevice" = 9238 | | "USBSpeed" = 3 | | "idProduct" = 36886 | | "IOServiceDEXTEntitlements" = (("com.apple.developer.driverkit.transport.usb")) | | "bInterfaceSubClass" = 0 | | "bConfigurationValue" = 1 | | "locationID" = 34734080 | | "USB Product Name" = "TETRA PEI interface" | | "bInterfaceProtocol" = 0 | | "iInterface" = 0 | | "bAlternateSetting" = 0 | | "idVendor" = 3245 | | "bInterfaceNumber" = 0 | | "bInterfaceClass" = 255 | | "bNumEndpoints" = 2 | | } | | | +-o lghub_agent <class AppleUSBHostInterfaceUserClient, id 0x100002988, !registered, !matched, active, busy 0, retain 6> | { | "UsbUserClientBufferStatistics" = {"IOMemoryDescriptor"=0,"IOBufferMemoryDescriptor"=0,"IOSubMemoryDescriptor"=0} | "IOUserClientCreator" = "pid 1438, lghub_agent" | "UsbUserClientBufferAllocations" = {"Bytes"=0,"Descriptors"=0} | "IOUserClientDefaultLocking" = Yes | } | +-o IOUSBHostInterface@1 <class IOUSBHostInterface, id 0x100002987, registered, matched, active, busy 0 (5 ms), retain 9> | { | "USBPortType" = 0 | "IOCFPlugInTypes" = {"2d9786c6-9ef3-11d4-ad51-000a27052861"="IOUSBHostFamily.kext/Contents/PlugIns/IOUSBLib.bundle"} | "USB Vendor Name" = "Motorola Solutions, Inc." | "bcdDevice" = 9238 | "USBSpeed" = 3 | "idProduct" = 36886 | "IOServiceDEXTEntitlements" = (("com.apple.developer.driverkit.transport.usb")) | "bInterfaceSubClass" = 0 | "bConfigurationValue" = 1 | "locationID" = 34734080 | "USB Product Name" = "TETRA PEI interface" | "bInterfaceProtocol" = 0 | "iInterface" = 0 | "bAlternateSetting" = 0 | "idVendor" = 3245 | "bInterfaceNumber" = 1 | "bInterfaceClass" = 255 | "bNumEndpoints" = 2 | } | +-o lghub_agent <class AppleUSBHostInterfaceUserClient, id 0x10000298a, !registered, !matched, active, busy 0, retain 6> { "UsbUserClientBufferStatistics" = {"IOMemoryDescriptor"=0,"IOBufferMemoryDescriptor"=0,"IOSubMemoryDescriptor"=0} "IOUserClientCreator" = "pid 1438, lghub_agent" "UsbUserClientBufferAllocations" = {"Bytes"=0,"Descriptors"=0} "IOUserClientDefaultLocking" = Yes } more details in my comment.

I've added my Vendor ID to the appropriate entitlement files but my binary fails validation when trying to upload it to the store for distribution. The embeded.mobileprovision file in the generated archive shows an asterisk instead of my approved Vendor ID. How can I make sure the embedded provisioning file has my Vendor ID?

Trying to use IOLog to print out a message from a dext. When I try to use IOLog, I get , though I did not or thought I did not tag it as private. I have tried to update the info.plist file for the dext according to https://developer.apple.com/forums/thread/705810, but that has not helped, or perhaps I am not defining it correctly since it's a dext. Anyone else had this issue, and how did you fix it?

I am having similar problems to this guy on Stack Overflow over a year ago: https://stackoverflow.com/questions/77627852/functions-of-iouserscsiperipheraldevicetype00-class-in-scsiperipheralsdriverkit There are also a few questions on this forum about this object, none of which have answers. I can get my driver to match and instantiate, but nobody calls my UserDetermineDeviceCharacteristics (which does nothing, just returns kIOReturnSuccess) I can attempt to call UserSuspendServices(), UserResumeServices() or UserReportMediumBlockSize() and all of them return kIOReturnUnsupported. It doesn't matter if I've unmounted the disk or not. Is the custom driver supposed to be instantiated beside the kernel's IOSCSIPeripheralDeviceType00, or should it replace it? What should its IOProviderClass be? What should its IOClass be - IOUserService, or something else? see FB19678139 and FB19677920