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Fails to capture IOUSBHostInterface with macOS 15.3 despite root privileges in app
I have an app that captures USB storage device and sends some commands to it. The app has a privilege helper tool which captures the USB device. Everything was working fine upto macOS 15.2 but it 15.3 update broke the functionality. When the helper tool tries to capture the USB device, it is able to capture IOUSBHostDevice but fails to capture IOUSBHostInterface. The error is Code: 3758097097; Domain: IOUSBHostErrorDomain; Description: Failed to create IOUSBHostInterface.; Reason: Failed [super init] I have verified the UID, EUID, GID, EGID = 0 for the helper process. So by IOUSBHost documentation it should have worked. The code that cause the error inside the helper tool is func captureUSBInterface(interface: io_service_t) -> IOUSBHostInterface? { let queue = DispatchQueue(label: "com.example.usbdevice.queue2") var capturedInterface: IOUSBHostInterface? do { capturedInterface = try IOUSBHostInterface(__ioService: interface, options: .deviceCapture, queue: queue, interestHandler: nil) } catch { NSLog("Failed to capture USB interface: \(error)") return nil } return capturedInterface } The app has sandbox=False and is distributed outside of the App Store. Please advise (long-term, short-term solutions) on how to make this work.
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2
530
Feb ’25
howto measure time_interval since physical plugin of a USB-gadget ?
=1) The situation: 1A) I make both a "DExt" and a "SDK" for still-imaging-USB-gadgets and MACOS>=14 ,iPADOS>=17 1B) One of the USB-gadgets needs warm_up after PlugIn (i.e End-User-App must know "now-TheMomentOfPlugIn" with precision ~1sec). =2) The question is how to do "1B" rationally? =3) My speculative guess: in BSD-descendant I expect existence (somewhere) of a "normal file" through "macports etc", which has normal "file creation time". Such a "file creation time" (accessible better via IORegistryEntry... at SDK-level; possibly via IOUSBHostInterface at DExt-level) is cognitive target of mine. =4) Additional constraints: Technically absent. I freely modify code either DExt (descendant of IOUSBHostInterface) or SDK-level (IORegistryEntryGetRegistryEntryID, IORegistryEntry...)
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622
Feb ’25
No logs from log stream | grep CompanyName
I have USB DriverKit driver. When I use the log command below to get log, there is logs from my driver on my own M-series MacBook where the driver is built using developer account. log stream | grep CompanyName But on other mac like (M-series) Mac Mini, there is no log captured from driver though the driver is communicating with the machine correctly. The only log captured are from MacOS regarding CompanyName driver status/unload/load. The MacOS is Sonoma 14.7.2 and 14.7.3. Please advise on how to get log from driver since writing to files is not allowed in DriverKit. I need logs to troubleshoot on Mac Mini. Thanks.
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491
Feb ’25
Implementing a virtual serial port using DriverKit/SerialDriverKit
I'm trying to implement a virtual serial port driver for my ham radio projects which require emulating some serial port devices and I need to have a "backend" to translate the commands received by the virtual serial port into some network-based communications. I think the best way to do that is to subclass IOUserSerial? Based on the available docs on this class (https://developer.apple.com/documentation/serialdriverkit/iouserserial), I've done the basic implementation below. When the driver gets loaded, I can see sth like tty.serial-1000008DD in /dev and I can use picocom to do I/O on the virtual serial port. And I see TxDataAvailable() gets called every time I type a character in picocom. The problems are however, firstly, when TxDataAvailable() is called, the TX buffer is all-zero so although the driver knows there is some incoming data received from picocom, it cannot actually see the data in neither Tx/Rx buffers. Secondly, I couldn't figure out how to notify the system that there are data available for sending back to picocom. I call RxDataAvailable(), but nothing appears on picocom, and RxFreeSpaceAvailable() never gets called back. So I think I must be doing something wrong somewhere. Really appreciate it if anyone could point out how should I fix it, many thanks! VirtualSerialPortDriver.cpp: constexpr int bufferSize = 2048; using SerialPortInterface = driverkit::serial::SerialPortInterface; struct VirtualSerialPortDriver_IVars {     IOBufferMemoryDescriptor *ifmd, *rxq, *txq;     SerialPortInterface *interface;     uint64_t rx_buf, tx_buf;     bool dtr, rts; }; bool VirtualSerialPortDriver::init() {     bool result = false;     result = super::init();     if (result != true)     {         goto Exit;     }     ivars = IONewZero(VirtualSerialPortDriver_IVars, 1);     if (ivars == nullptr)     {         goto Exit;     }     kern_return_t ret;     ret = ivars->rxq->Create(kIOMemoryDirectionInOut, bufferSize, 0, &ivars->rxq);     if (ret != kIOReturnSuccess) {         goto Exit;     }     ret = ivars->txq->Create(kIOMemoryDirectionInOut, bufferSize, 0, &ivars->txq);     if (ret != kIOReturnSuccess) {         goto Exit;     }     IOAddressSegment ioaddrseg;     ivars->rxq->GetAddressRange(&ioaddrseg);     ivars->rx_buf = ioaddrseg.address;     ivars->txq->GetAddressRange(&ioaddrseg);     ivars->tx_buf = ioaddrseg.address;     return true; Exit:     return false; } kern_return_t IMPL(VirtualSerialPortDriver, HwActivate) {     kern_return_t ret;     ret = HwActivate(SUPERDISPATCH);     if (ret != kIOReturnSuccess) {         goto Exit;     }     // Loopback, set CTS to RTS, set DSR and DCD to DTR     ret = SetModemStatus(ivars->rts, ivars->dtr, false, ivars->dtr);     if (ret != kIOReturnSuccess) {         goto Exit;     } Exit:     return ret; } kern_return_t IMPL(VirtualSerialPortDriver, HwDeactivate) {     kern_return_t ret;     ret = HwDeactivate(SUPERDISPATCH);     if (ret != kIOReturnSuccess) {         goto Exit;     } Exit:     return ret; } kern_return_t IMPL(VirtualSerialPortDriver, Start) {     kern_return_t ret;   ret = Start(provider, SUPERDISPATCH);     if (ret != kIOReturnSuccess) {         return ret;     }     IOMemoryDescriptor *rxq_, *txq_;     ret = ConnectQueues(&ivars->ifmd, &rxq_, &txq_, ivars->rxq, ivars->txq, 0, 0, 11, 11);     if (ret != kIOReturnSuccess) {         return ret;     }     IOAddressSegment ioaddrseg;     ivars->ifmd->GetAddressRange(&ioaddrseg);     ivars->interface = reinterpret_cast<SerialPortInterface*>(ioaddrseg.address);     SerialPortInterface &intf = *ivars->interface;     ret = RegisterService();     if (ret != kIOReturnSuccess) {         goto Exit;     }     TxFreeSpaceAvailable(); Exit:     return ret; } void IMPL(VirtualSerialPortDriver, TxDataAvailable) {     SerialPortInterface &intf = *ivars->interface;     // Loopback     // FIXME consider wrapped case     size_t tx_buf_sz = intf.txPI - intf.txCI;     void *src = reinterpret_cast<void *>(ivars->tx_buf + intf.txCI); //    char src[] = "Hello, World!";     void *dest = reinterpret_cast<void *>(ivars->rx_buf + intf.rxPI);     memcpy(dest, src, tx_buf_sz);     intf.rxPI += tx_buf_sz;     RxDataAvailable();     intf.txCI = intf.txPI;     TxFreeSpaceAvailable();     Log("[TX Buf]: %{public}s", reinterpret_cast<char *>(ivars->tx_buf));     Log("[RX Buf]: %{public}s", reinterpret_cast<char *>(ivars->rx_buf)); // dmesg confirms both buffers are all-zero     Log("[TX] txPI: %d, txCI: %d, rxPI: %d, rxCI: %d, txqoffset: %d, rxqoffset: %d, txlogsz: %d, rxlogsz: %d",         intf.txPI, intf.txCI, intf.rxPI, intf.rxCI, intf.txqoffset, intf.rxqoffset, intf.txqlogsz, intf.rxqlogsz); } void IMPL(VirtualSerialPortDriver, RxFreeSpaceAvailable) {     Log("RxFreeSpaceAvailable() called!"); } kern_return_t   IMPL(VirtualSerialPortDriver,HwResetFIFO){     Log("HwResetFIFO() called with tx: %d, rx: %d!", tx, rx);     kern_return_t ret = kIOReturnSuccess;     return ret; } kern_return_t   IMPL(VirtualSerialPortDriver,HwSendBreak){     Log("HwSendBreak() called!");     kern_return_t ret = kIOReturnSuccess;     return ret; } kern_return_t   IMPL(VirtualSerialPortDriver,HwProgramUART){     Log("HwProgramUART() called, BaudRate: %u, nD: %d, nS: %d, P: %d!", baudRate, nDataBits, nHalfStopBits, parity);     kern_return_t ret = kIOReturnSuccess;     return ret; }      kern_return_t   IMPL(VirtualSerialPortDriver,HwProgramBaudRate){     Log("HwProgramBaudRate() called, BaudRate = %d!", baudRate);     kern_return_t ret = kIOReturnSuccess;     return ret; } kern_return_t   IMPL(VirtualSerialPortDriver,HwProgramMCR){     Log("HwProgramMCR() called, DTR: %d, RTS: %d!", dtr, rts);     ivars->dtr = dtr;     ivars->rts = rts;     kern_return_t ret = kIOReturnSuccess; Exit:     return ret; } kern_return_t  IMPL(VirtualSerialPortDriver, HwGetModemStatus){     *cts = ivars->rts;     *dsr = ivars->dtr;     *ri = false;     *dcd = ivars->dtr;     Log("HwGetModemStatus() called, returning CTS=%d, DSR=%d, RI=%d, DCD=%d!", *cts, *dsr, *ri, *dcd);     kern_return_t ret = kIOReturnSuccess;     return ret; } kern_return_t   IMPL(VirtualSerialPortDriver,HwProgramLatencyTimer){     Log("HwProgramLatencyTimer() called!");     kern_return_t ret = kIOReturnSuccess;     return ret; } kern_return_t   IMPL(VirtualSerialPortDriver,HwProgramFlowControl){     Log("HwProgramFlowControl() called! arg: %u, xon: %d, xoff: %d", arg, xon, xoff);     kern_return_t ret = kIOReturnSuccess; Exit:     return ret; }
1
0
2.1k
Feb ’25
Looking for USBSerialDriver sample code
I would like to write a driver that supports our custom USB-C connected device, which provides a serial port interface. USBSerialDriverKit looks like the solution I need. Unfortunately, without a decent sample, I'm not sure how to accomplish this. The DriverKit documentation does a good job of telling me what APIs exist but it is very light on semantic information and details about how to use all of these API elements. A function call with five unexplained parameters just is that useful to me. Does anyone have or know of a resource that can help me figure out how to get started?
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727
Feb ’25
iphone mirroring
Hi Team , I want to create a system where i can mirror the iPhone screen connected through USB and control it from the web browser. can anyone help me ? Thanks , Mukta
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0
386
Jan ’25
Crash in IOService::Create
I am getting an unexpected crash from IOService::Create() when attempting to create a new user-client. The crash is a nullptr exception in OSCopyInObjects(). The last call from my code was IOService::Create(). As far as I can tell, all the input parameters to Create() are correct, and the Info.plist is has the correct key and class information - indeed, if I corrupt these I get an error status return rather than a crash. Any suggestions as to what could be causing this? I suspect that the problem may be related from a change in the underlying application that is creating the user client. This was modified from a standard app to a daemon, following the advice here: https://developer.apple.com/documentation/xcode/signing-a-daemon-with-a-restricted-entitlement. However, it is the driver that crashes - not the host opening the user client.
1
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527
Jan ’25