Очень полезная статья https://lihashgnis.blogspot.com/2018/07/getting-descriptors-from-usb-device.html
Я только что добавил код для получения String Descriptor:
USB_STRING_DESCRIPTOR* stringDescriptor = nullptr;
int sBufferSize = sizeof(USB_DESCRIPTOR_REQUEST) + MAXIMUM_USB_STRING_LENGTH;
BYTE *sBuffer = new BYTE[sBufferSize];
memset(sBuffer, 0, sBufferSize);
requestPacket = (USB_DESCRIPTOR_REQUEST*)sBuffer;
stringDescriptor = (USB_STRING_DESCRIPTOR*)((BYTE*)sBuffer + sizeof(USB_DESCRIPTOR_REQUEST));
requestPacket->SetupPacket.bmRequest = 0x80;
requestPacket->SetupPacket.bRequest = USB_REQUEST_GET_DESCRIPTOR;
requestPacket->ConnectionIndex = usbPortNumber;
requestPacket->SetupPacket.wValue = (USB_STRING_DESCRIPTOR_TYPE << 8); // String Descriptior 0
requestPacket->SetupPacket.wLength = MAXIMUM_USB_STRING_LENGTH;
err = DeviceIoControl(hUsbHub, IOCTL_USB_GET_DESCRIPTOR_FROM_NODE_CONNECTION, sBuffer, sBufferSize, sBuffer, sBufferSize, &bytesReturned, nullptr);
// Now get iProduct string in language at zero index
requestPacket->SetupPacket.wValue = (USB_STRING_DESCRIPTOR_TYPE << 8) | deviceDescriptor->iProduct;
requestPacket->SetupPacket.wIndex = (USHORT)stringDescriptor->bString[0];
err = DeviceIoControl(hUsbHub, IOCTL_USB_GET_DESCRIPTOR_FROM_NODE_CONNECTION, sBuffer, sBufferSize, sBuffer, sBufferSize, &bytesReturned, nullptr);
std::wcout << stringDescriptor->bString