windows Driver Maintenance(wfp driver)

During Windows driver development, you can use various methods to record driver logs for troubleshooting. The following are common methods:

• Use the DbgPrint function: The DbgPrint function can output the information to the kernel debugger, such as the DebugView tool, but it is not convenient to view it in the future troubleshooting. There are tools you can use to save it to a file.

• Use ETW(Event Tracing for Windows) : ETW is a high-performance event tracing technique built into Windows operating system, which can monitor and debug operating systems, applications, drivers, etc. The driver can also use ETW to output log information to the ETW session and use some tools to save the log information to a file for later troubleshooting.

• Windows Software Trace Preprocessor(WPP) : WPP is a built-in trace information preprocessor of the Windows operating system. It converts the log information in the driver program into formatted output, facilitating subsequent troubleshooting. You can save the output generated by WPP directly to a file, or you can use some tools to save it to a file.

It is important to note that in the production environment, excessive log information should be avoided in the driver to avoid affecting system performance. If you need to debug in a production environment, you can use technologies such as ETW for remote tracing.

This answer quotes ChatGPT

Windows drivers typically use kernel debuggers to output debugging information, because they run in operating system kernel space and do not have direct access to the file system, so writing logs to files requires some special handling.

The following methods are used to print and store logs on the driver side:

1. Using the kernel debugger
The kernel debugger is a tool that outputs debugging information in kernel mode. By configuring the kernel debugger, you can print the driver side logs to the debugger console or remote debugging tools, and then view and analyze the logs using the debugger's log window or exporting log files.

2. Write to system logs
Windows provides a system log service, allowing drivers to write log information to system logs. Using the system log service, you can easily record driver logs to system log files for subsequent view and analysis.

3, Create a device object
A driver can create a device object that allows an application to read and write device objects by calling a specific driver interface. The driver can send the log information as output data to the device object to the application, which can save the data to a file or print it to the console.

4. Using memory mapped files
Drivers can create a memory mapped file object that allows applications to read and write file data through memory mapped files. The driver can write log information to a memory-mapped file object, and the application can then read the data in the file for subsequent viewing and analysis.

In general, the choice depends on the application scenario and specific requirements. If you want to see debugging information in real time, it might be more convenient to use a kernel debugger or create a device object; If you need to save log information to a file, you can use system logs or memory mapped files.

Because the code for Windows drivers is complex and needs to be customized for specific application scenarios and requirements, it is difficult to give a general complete code example. However, I can give you a few snippets of code so you can see how to implement the different logging methods.

Here is sample code to output log information using the kernel debugger:

#include 
#include 

// 驱动程序入口函数
NTSTATUS DriverEntry(PDRIVER_OBJECT driverObject, PUNICODE_STRING registryPath)
{
    // 启用内核调试器输出
    DbgPrint("Hello, world!\n");

    return STATUS_SUCCESS;
}

The code snippet above shows how to use the kernel debugger to output a simple debug message. When using this approach, you need to wire the driver to the debugger. You can use a debugger such as Windbg or Dbgview to capture the output debugging information.

Here is sample code for logging using the system logging service:

#include 
#include 
#include 

// 定义系统日志服务的名称和事件ID
#define LOG_SERVICE_NAME L"MyLogService"
#define LOG_EVENT_ID 1000

// 驱动程序入口函数
NTSTATUS DriverEntry(PDRIVER_OBJECT driverObject, PUNICODE_STRING registryPath)
{
    // 注册系统日志服务
    UNICODE_STRING logServiceName;
    RtlInitUnicodeString(&logServiceName, LOG_SERVICE_NAME);
    HANDLE logHandle = NULL;
    NTSTATUS status = IoCreateNotificationEvent(&logServiceName, &logHandle);
    if (!NT_SUCCESS(status))
    {
        // 处理错误
        return status;
    }

    // 输出日志信息到系统日志服务
    UNICODE_STRING logMessage;
    RtlInitUnicodeString(&logMessage, L"Hello, world!");
    IoWriteErrorLogEntry(&logMessage, LOG_EVENT_ID, NULL, 0, NULL, 0);

    // 关闭系统日志服务句柄
    ZwClose(logHandle);

    return STATUS_SUCCESS;
}

The code snippet above shows how to log a simple log message using the system logging service. To use this method, you need to register a unique log service name for the driver and write the log information to the system log using the IoWriteErrorLogEntry function.

Here is sample code for creating a device object to output log information to:

#include 

// 定义设备对象的名称和GUID
#define LOG_DEVICE_NAME L"\\Device\\MyLogDevice"
#define LOG_DEVICE_GUID {0x2dc53b30, 0x6bd3, 0x11e8, {0x9c, 0x6f, 0x00, 0x02, 0xe5, 0x8c, 0x2a, 0x34}}

// 定义IOCTL代码
#define IOCTL_LOG_WRITE CTL_CODE(FILE_DEVICE_UNKNOWN, 0x800, METHOD_BUFFERED, FILE_WRITE_DATA)

// 驱动程序入口函数
NTSTATUS DriverEntry(PDRIVER_OBJECT driverObject, PUNICODE_STRING registryPath)
{
    // 创建设备对象
    UNICODE_STRING deviceName;
    RtlInitUnicodeString(&deviceName, LOG_DEVICE_NAME);
    PDEVICE_OBJECT deviceObject = NULL;
    NTSTATUS status = IoCreateDevice(driverObject, 0, &deviceName, FILE_DEVICE_UNKNOWN, 0, FALSE, &deviceObject);
    if (!NT_SUCCESS(status))
    {
        // 处理错误
        return status;
    }

    // 设置设备对象的IOCTL处理函数
    driverObject->MajorFunction[IRP_MJ_DEVICE_CONTROL] = LogDeviceIoControl;

    // 输出日志信息到设备对象
    UNICODE_STRING logMessage;
    RtlInitUnicodeString(&logMessage, L"Hello, world!");
    LogDeviceWrite(deviceObject, &logMessage);

    return STATUS_SUCCESS;
}

// 设备对象的IOCTL处理函数
NTSTATUS LogDeviceIoControl(PDEVICE_OBJECT deviceObject, PIRP irp)
{
    PIO_STACK_LOCATION stack = IoGetCurrentIrpStackLocation(irp);
    NTSTATUS status = STATUS_SUCCESS;

    switch (stack->Parameters.DeviceIoControl.IoControlCode)
    {
    case IOCTL_LOG_WRITE:
        {
            // 获取输入缓冲区的日志信息
            PVOID buffer = irp->AssociatedIrp.SystemBuffer;
            ULONG inputLength = stack->Parameters.DeviceIoControl.InputBufferLength;

            // 将日志信息输出到控制台
            DbgPrint("%.*S\n", inputLength, (PWSTR)buffer);

            // 完成IRP并返回结果
            irp->IoStatus.Status = STATUS_SUCCESS;
            irp->IoStatus.Information = 0;
            IoCompleteRequest(irp, IO_NO_INCREMENT);
            break;
        }
    default:
        status = STATUS_INVALID_DEVICE_REQUEST;
        break;
    }

    return status;
}

// 将日志信息写入设备对象
NTSTATUS LogDeviceWrite(PDEVICE_OBJECT deviceObject, PUNICODE_STRING logMessage)
{
    // 创建IRP并发送IOCTL请求
    ULONG inputLength = logMessage->Length;
    PIRP irp = IoBuildDeviceIoControlRequest(IOCTL_LOG_WRITE, deviceObject, logMessage->Buffer, inputLength, NULL, 0, FALSE, NULL, NULL);
    if (irp == NULL)
    {
        return STATUS_INSUFFICIENT_RESOURCES;
    }

    // 发送IRP并等待完成
    KEVENT event;
    KeInitializeEvent(&event, NotificationEvent, FALSE);
    IoSetCompletionRoutine(irp, LogDeviceCompletionRoutine, &event, TRUE, TRUE, TRUE);
    NTSTATUS status = IoCallDriver(deviceObject, irp);
    #include 

// 定义设备对象的名称和GUID
#define LOG_DEVICE_NAME L"\\Device\\MyLogDevice"
#define LOG_DEVICE_GUID {0x2dc53b30, 0x6bd3, 0x11e8, {0x9c, 0x6f, 0x00, 0x02, 0xe5, 0x8c, 0x2a, 0x34}}

// 定义IOCTL代码
#define IOCTL_LOG_WRITE CTL_CODE(FILE_DEVICE_UNKNOWN, 0x800, METHOD_BUFFERED, FILE_WRITE_DATA)

// 驱动程序入口函数
NTSTATUS DriverEntry(PDRIVER_OBJECT driverObject, PUNICODE_STRING registryPath)
{
    // 创建设备对象
    UNICODE_STRING deviceName;
    RtlInitUnicodeString(&deviceName, LOG_DEVICE_NAME);
    PDEVICE_OBJECT deviceObject = NULL;
    NTSTATUS status = IoCreateDevice(driverObject, 0, &deviceName, FILE_DEVICE_UNKNOWN, 0, FALSE, &deviceObject);
    if (!NT_SUCCESS(status))
    {
        // 处理错误
        return status;
    }

    // 设置设备对象的IOCTL处理函数
    driverObject->MajorFunction[IRP_MJ_DEVICE_CONTROL] = LogDeviceIoControl;

    // 输出日志信息到设备对象
    UNICODE_STRING logMessage;
    RtlInitUnicodeString(&logMessage, L"Hello, world!");
    LogDeviceWrite(deviceObject, &logMessage);

    return STATUS_SUCCESS;
}

// 设备对象的IOCTL处理函数
NTSTATUS LogDeviceIoControl(PDEVICE_OBJECT deviceObject, PIRP irp)
{
    PIO_STACK_LOCATION stack = IoGetCurrentIrpStackLocation(irp);
    NTSTATUS status = STATUS_SUCCESS;

    switch (stack->Parameters.DeviceIoControl.IoControlCode)
    {
    case IOCTL_LOG_WRITE:
        {
            // 获取输入缓冲区的日志信息
            PVOID buffer = irp->AssociatedIrp.SystemBuffer;
            ULONG inputLength = stack->Parameters.DeviceIoControl.InputBufferLength;

            // 将日志信息输出到控制台
            DbgPrint("%.*S\n", inputLength, (PWSTR)buffer);

            // 完成IRP并返回结果
            irp->IoStatus.Status = STATUS_SUCCESS;
            irp->IoStatus.Information = 0;
            IoCompleteRequest(irp, IO_NO_INCREMENT);
            break;
        }
    default:
        status = STATUS_INVALID_DEVICE_REQUEST;
        break;
    }

    return status;
}

// 将日志信息写入设备对象
NTSTATUS LogDeviceWrite(PDEVICE_OBJECT deviceObject, PUNICODE_STRING logMessage)
{
    // 创建IRP并发送IOCTL请求
    ULONG inputLength = logMessage->Length;
    PIRP irp = IoBuildDeviceIoControlRequest(IOCTL_LOG_WRITE, deviceObject, logMessage->Buffer, inputLength, NULL, 0, FALSE, NULL, NULL);
    if (irp == NULL)
    {
        return STATUS_INSUFFICIENT_RESOURCES;
    }

    // 发送IRP并等待完成
    KEVENT event;
    KeInitializeEvent(&event, NotificationEvent, FALSE);
    IoSetCompletionRoutine(irp, LogDeviceCompletionRoutine, &event, TRUE, TRUE, TRUE);
    NTSTATUS status = IoCallDriver(deviceObject, irp);
    if

Using GPT and your own ideas, in Windows drivers, you can write messages to text files using the driver write to log file method. Here are some possible approaches:

1. Use the internal Windows logging API: Windows drivers can use the Windows logging API to write messages to the Windows event log or ETW log, which can be viewed in the Windows system log. You can export and analyze event logs using the Logman or Tracerpt tools, which can be used to filter and query events in log files.

2. Use file system operations: Drivers can use kernel apis such as ZwCreateFile, ZwWriteFile, etc., to write messages to text files. Text can be written to the file by calling ZwCreateFile to open it and passing the file handle to ZwWriteFile. When debugging, you can view logging information by reading the text file into the editor.

3. Use third-party libraries: You can also use third-party libraries, such as Log4Net, NLog, etc., to log in the driver. These libraries typically provide configuration options such as log level, output format, and so on.

Note that logging in a driver can have a performance impact, especially in a production environment. Therefore, use logging when necessary to avoid impact on system performance.

Another common method is to use the Event Tracing for Windows(ETW) mechanism in the driver. ETW can help you log various events at the driver runtime, including debugging information, error information, performance data, and so on. ETW recorded data can be written directly to the built-in log file of the Windows system, or can be viewed in real time or offline using specialized ETW tools. Here is a simple example code that demonstrates how to use ETW for event logging in a driver:

#include 

TRACEHANDLE g_hTrace = INVALID_PROCESSTRACE_HANDLE;

NTSTATUS InitTrace()
{
    NTSTATUS status = STATUS_SUCCESS;
    ULONG ulBufferSize = 0;

    // 获取缓冲区大小
    status = EventTraceProperties(NULL, EventTraceInformation, NULL, 0, &ulBufferSize);
    if (status != STATUS_BUFFER_TOO_SMALL)
        return status;

    // 分配缓冲区
    PEVENT_TRACE_PROPERTIES pTraceProp = (PEVENT_TRACE_PROPERTIES)ExAllocatePoolWithTag(PagedPool, ulBufferSize, 'ETW ');
    if (!pTraceProp)
        return STATUS_INSUFFICIENT_RESOURCES;

    // 初始化TRACE_PROPERTIES结构
    RtlZeroMemory(pTraceProp, ulBufferSize);
    pTraceProp->Wnode.BufferSize = ulBufferSize;
    pTraceProp->Wnode.Guid = SystemTraceControlGuid;
    pTraceProp->Wnode.ClientContext = 1;  // 请求实时处理
    pTraceProp->LogFileMode |= EVENT_TRACE_REAL_TIME_MODE;  // 实时记录模式

    // 启动ETW会话
    status = StartTrace(&g_hTrace, L"MyDriver", pTraceProp);
    if (status != STATUS_SUCCESS)
    {
        ExFreePoolWithTag(pTraceProp, 'ETW ');
        return status;
    }

    ExFreePoolWithTag(pTraceProp, 'ETW ');

    return STATUS_SUCCESS;
}

NTSTATUS UninitTrace()
{
    if (g_hTrace == INVALID_PROCESSTRACE_HANDLE)
        return STATUS_SUCCESS;

    // 停止ETW会话
    StopTrace(g_hTrace, L"MyDriver", NULL);

    g_hTrace = INVALID_PROCESSTRACE_HANDLE;

    return STATUS_SUCCESS;
}

VOID TraceEvent(LPCGUID pGuid, UCHAR ubLevel, ULONGLONG ullKeyword, LPCWSTR pwszMessage)
{
    if (g_hTrace == INVALID_PROCESSTRACE_HANDLE)
        return;

    EVENT_TRACE_HEADER Header;
    RtlZeroMemory(&Header, sizeof(EVENT_TRACE_HEADER));
    Header.Size = sizeof(EVENT_TRACE_HEADER);
    Header.Flags = WNODE_FLAG_TRACED_GUID;
    Header.Guid = *pGuid;

    EVENT_TRACE_UNICODE_STRING UniStr;
    RtlZeroMemory(&UniStr, sizeof(EVENT_TRACE_UNICODE_STRING));
    UniStr.Length = wcslen(pwszMessage) * sizeof(WCHAR);
    UniStr.Buffer = (WCHAR*)pwszMessage;

    EventWrite(g_hTrace, &Header, NULL, 1, &UniStr, NULL, 0, NULL);
}

The code above demonstrates how to start an ETW session, stop an ETW session, and log an event. You can call the TraceEvent function where you want to record an event, passing the event information as a parameter.

This answer quotes chatgpt
Windows Driver maintenance refers to maintaining and managing the drivers used by the Windows operating system to ensure the stability and normal running of the system. Here are some common tasks for Windows driver maintenance:

Update drivers regularly: Drivers can be updated through the device manager that comes with Windows, or you can download the latest version of the driver from the official website of the hardware manufacturer.
Uninstalling useless drivers: Uninstalls drivers that are no longer used in the device manager to free up system resources and reduce potential conflicts.
Resolve driver conflicts: If drivers used by different devices conflict, the system may become unstable or fail to work properly. You can view conflicts from the Resources TAB of the device Manager and try to resolve them.
Diagnose and fix driver problems: If a device is not working properly, it may be because there is a problem with the driver. You can use the device manager that comes with Windows or third-party tools to diagnose and fix driver problems.
Create and Restore system backups: Before you update or change drivers, you should create a system backup to prevent problems. If problems arise after updating or changing drivers, you can use a system backup to restore the system to its previous state.
Maintaining Windows drivers can ensure the normal operation of the system and improve the performance and stability of the computer.