How do we compile a driverkit as library. Does this need any special entitlements?

I am working on a DriverKit project and the new class OSMappedFile sounds like something I am looking for, at least from what I understood from the description in the header file. https://developer.apple.com/documentation/driverkit/osmappedfile I've tried different combinations, however the method OSMappedFile::createFromPath always returns an error 0xe00002bc (general error), which is not helpful at all. Could you please provide more details about the class and how to use it? Is it possible to open an arbitrary file in an arbitrary location? Does the owner of the file matter? Does the entitlements have to be modified somehow? Thanks for reply I am testing it on Monterey 12.3.1, my driver is linking DriverKit 21.0, no provisioning profile, SIP is off.

Hi, I am trying to run an example driver project from https://developer.apple.com/documentation/driverkit/communicating_between_a_driverkit_extension_and_a_client_app?language=objc The project compiles fine, the driver extension is successfully installed and running, however when the client application tries to communicate with the driver (calls IOConnectCallScalarMethod CppUserClient/main.cpp, line 236), the driver crashes, even though there are no modifications of the example code. Does anybody know how to fix it? The project doesn't use any provisioning profile, all three targets are signed to run locally as described in the link. My system: MacOS 11.5.2 BigSur Apple M1 chip XCode 13.2.1 System Integrity Protection status: disabled. systemextensionsctl developer: Developer mode is on also ran command "sudo nvram boot-args=-arm64e_preview_abi" crash report program CppUserClient output

I read the example "Communicating Between a DriverKit Extension and a Client App". https://developer.apple.com/documentation/driverkit/communicating_between_a_driverkit_extension_and_a_client_app But I still don't know, can I communicate with DriverKit through SwiftUI APP? Instead of using IOServiceOpen in CppUserClient, can I use IOServiceOpen in SwiftUI APP like this? Or are there other options?

I've been creating a virtual ethernet interface. I've opened asynchronous communication with a controlling application and every time there are new packets, the controlling app is notified and then asks for the packet data. The packet data is stored in a simple struct, with uint8_t[1600] for the bytes, and uint32_t for the length. The dext is able to populate this struct with dummy data every time a packet is available, with the dummy data visible on the controlling application. However, I'm struggling to fill it with the real packet data. The IOUserNetworkPacket provides metadata about a packet. It contains a packets timestamp, size, etc, but it doesn't seem to contain the packet's data. There are the GetDataOffset() and GetMemorySegmentOffset() methods which seem to return byte offsets for where the packet data is located in their memory buffer. My instinct tells me to add this offset to the pointer of wherever the packet data is stored. The problem is I have no idea where the packets are actually stored. I know they are managed by the IOUserNetworkPacketBufferPool, but I don't think that's where their memory is. There is the CopyMemoryDescriptor() method which gives an IOMemoryDescriptor of its contents. I tried using the descriptor to create an IOMemoryMap, using it to call GetAddress(). The pointers to all the mentioned objects lead to junk data. I must be approaching this entirely wrong. If anyone knows how to access the packet data, or has any ideas, I would appreciate any help. Thanks.