本篇文章与上一篇文章《驱动开发：内核注册并监控对象回调》所使用的方式是一样的都是使用ObRegisterCallbacks注册回调事件，只不过上一篇博文中LyShark将回调结构体OB_OPERATION_REGISTRATION中的ObjectType填充为了PsProcessType和PsThreadType格式从而实现监控进程与线程，本章我们需要将该结构填充为IoFileObjectType以此来实现对文件的监控，文件过滤驱动不仅仅可以用来监控文件的打开，还可以用它实现对文件的保护，一旦驱动加载则文件是不可被删除和改动的。

与进程线程回调有少许的不同，文件回调需要开启驱动的TypeInfo.SupportsObjectCallbacks开关，并定义一些微软结构，如下是我们所需要的公开结构体，可在微软官方或WinDBG中获取到最新的，将其保存为lyshark.h方便后期引用。

// 署名权// right to sign one's name on a piece of work// PowerBy: LyShark// Email: me@lyshark.com#include #include typedef struct _CALLBACK_ENTRY{LIST_ENTRY CallbackList;OB_OPERATION  Operations;ULONG Active;PVOID Handle;POBJECT_TYPE ObjectType;POB_PRE_OPERATION_CALLBACK  PreOperation;POB_POST_OPERATION_CALLBACK PostOperation;ULONG unknown;} CALLBACK_ENTRY, *PCALLBACK_ENTRY;typedef struct _LDR_DATA                         // 24 elements, 0xE0 bytes (sizeof){/*0x000*/     struct _LIST_ENTRY InLoadOrderLinks;                     // 2 elements, 0x10 bytes (sizeof)/*0x010*/     struct _LIST_ENTRY InMemoryOrderLinks;                   // 2 elements, 0x10 bytes (sizeof)/*0x020*/     struct _LIST_ENTRY InInitializationOrderLinks;           // 2 elements, 0x10 bytes (sizeof)/*0x030*/     VOID*        DllBase;/*0x038*/     VOID*        EntryPoint;/*0x040*/     ULONG32      SizeOfImage;/*0x044*/     UINT8        _PADDING0_[0x4];/*0x048*/     struct _UNICODE_STRING FullDllName;                      // 3 elements, 0x10 bytes (sizeof)/*0x058*/     struct _UNICODE_STRING BaseDllName;                      // 3 elements, 0x10 bytes (sizeof)/*0x068*/     ULONG32      Flags;/*0x06C*/     UINT16       LoadCount;/*0x06E*/     UINT16       TlsIndex;union                                                    // 2 elements, 0x10 bytes (sizeof){/*0x070*/         struct _LIST_ENTRY HashLinks;                        // 2 elements, 0x10 bytes (sizeof)struct                                               // 2 elements, 0x10 bytes (sizeof){/*0x070*/             VOID*        SectionPointer;/*0x078*/             ULONG32      CheckSum;/*0x07C*/             UINT8        _PADDING1_[0x4];};};union                                                    // 2 elements, 0x8 bytes (sizeof){/*0x080*/         ULONG32      TimeDateStamp;/*0x080*/         VOID*        LoadedImports;};/*0x088*/     struct _ACTIVATION_CONTEXT* EntryPointActivationContext;/*0x090*/     VOID*        PatchInformation;/*0x098*/     struct _LIST_ENTRY ForwarderLinks;                       // 2 elements, 0x10 bytes (sizeof)/*0x0A8*/     struct _LIST_ENTRY ServiceTagLinks;                      // 2 elements, 0x10 bytes (sizeof)/*0x0B8*/     struct _LIST_ENTRY StaticLinks;                          // 2 elements, 0x10 bytes (sizeof)/*0x0C8*/     VOID*        ContextInformation;/*0x0D0*/     UINT64       OriginalBase;/*0x0D8*/     union _LARGE_INTEGER LoadTime;                           // 4 elements, 0x8 bytes (sizeof)}LDR_DATA, *PLDR_DATA;typedef struct _OBJECT_TYPE_INITIALIZER                                                                                                                                         // 25 elements, 0x70 bytes (sizeof){/*0x000*/     UINT16       Length;union                                                                                                                                                                       // 2 elements, 0x1 bytes (sizeof){/*0x002*/         UINT8        ObjectTypeFlags;struct                                                                                                                                                                  // 7 elements, 0x1 bytes (sizeof){/*0x002*/             UINT8        CaseInsensitive : 1;                                                                                                                                   // 0 BitPosition/*0x002*/             UINT8        UnnamedObjectsOnly : 1;                                                                                                                                // 1 BitPosition/*0x002*/             UINT8        UseDefaultObject : 1;                                                                                                                                  // 2 BitPosition/*0x002*/             UINT8        SecurityRequired : 1;                                                                                                                                  // 3 BitPosition/*0x002*/             UINT8        MaintainHandleCount : 1;                                                                                                                               // 4 BitPosition/*0x002*/             UINT8        MaintainTypeList : 1;                                                                                                                                  // 5 BitPosition/*0x002*/             UINT8        SupportsObjectCallbacks : 1;                                                                                                                           // 6 BitPosition};};/*0x004*/     ULONG32      ObjectTypeCode;/*0x008*/     ULONG32      InvalidAttributes;/*0x00C*/     struct _GENERIC_MAPPING GenericMapping;                                                                                                                                     // 4 elements, 0x10 bytes (sizeof)/*0x01C*/     ULONG32      ValidAccessMask;/*0x020*/     ULONG32      RetainAccess;/*0x024*/     enum _POOL_TYPE PoolType;/*0x028*/     ULONG32      DefaultPagedPoolCharge;/*0x02C*/     ULONG32      DefaultNonPagedPoolCharge;/*0x030*/     PVOID DumpProcedure;/*0x038*/     PVOID OpenProcedure;/*0x040*/     PVOID CloseProcedure;/*0x048*/     PVOID DeleteProcedure;/*0x050*/     PVOID ParseProcedure;/*0x058*/     PVOID SecurityProcedure;/*0x060*/     PVOID QueryNameProcedure;/*0x068*/     PVOID OkayToCloseProcedure;}OBJECT_TYPE_INITIALIZER, *POBJECT_TYPE_INITIALIZER;typedef struct _EX_PUSH_LOCK                 // 7 elements, 0x8 bytes (sizeof){union                                    // 3 elements, 0x8 bytes (sizeof){struct                               // 5 elements, 0x8 bytes (sizeof){/*0x000*/             UINT64       Locked : 1;         // 0 BitPosition/*0x000*/             UINT64       Waiting : 1;        // 1 BitPosition/*0x000*/             UINT64       Waking : 1;         // 2 BitPosition/*0x000*/             UINT64       MultipleShared : 1; // 3 BitPosition/*0x000*/             UINT64       Shared : 60;        // 4 BitPosition};/*0x000*/         UINT64       Value;/*0x000*/         VOID*        Ptr;};}EX_PUSH_LOCK, *PEX_PUSH_LOCK;typedef struct _MY_OBJECT_TYPE                   // 12 elements, 0xD0 bytes (sizeof){/*0x000*/     struct _LIST_ENTRY TypeList;              // 2 elements, 0x10 bytes (sizeof)/*0x010*/     struct _UNICODE_STRING Name;              // 3 elements, 0x10 bytes (sizeof)/*0x020*/     VOID*        DefaultObject;/*0x028*/     UINT8        Index;/*0x029*/     UINT8        _PADDING0_[0x3];/*0x02C*/     ULONG32      TotalNumberOfObjects;/*0x030*/     ULONG32      TotalNumberOfHandles;/*0x034*/     ULONG32      HighWaterNumberOfObjects;/*0x038*/     ULONG32      HighWaterNumberOfHandles;/*0x03C*/     UINT8        _PADDING1_[0x4];/*0x040*/     struct _OBJECT_TYPE_INITIALIZER TypeInfo; // 25 elements, 0x70 bytes (sizeof)/*0x0B0*/     struct _EX_PUSH_LOCK TypeLock;            // 7 elements, 0x8 bytes (sizeof)/*0x0B8*/     ULONG32      Key;/*0x0BC*/     UINT8        _PADDING2_[0x4];/*0x0C0*/     struct _LIST_ENTRY CallbackList;          // 2 elements, 0x10 bytes (sizeof)}MY_OBJECT_TYPE, *PMY_OBJECT_TYPE;

对于开启了TypeInfo.SupportsObjectCallbacks属性的驱动来说自然就支持文件路径转换，当系统中有文件被加载则自动执行LySharkFileObjectpreCall回调事件，过滤掉无效路径后即可直接输出，完整代码如下所示；

// 署名权// right to sign one's name on a piece of work// PowerBy: LyShark// Email: me@lyshark.com#include "lyshark.h"PVOID obHandle;DRIVER_INITIALIZE DriverEntry;// 文件回调OB_PREOP_CALLBACK_STATUS LySharkFileObjectpreCall(PVOID RegistrationContext, POB_PRE_OPERATION_INFORMATION OperationInformation){UNICODE_STRING DosName;PFILE_OBJECT fileo = OperationInformation->Object;HANDLE CurrentProcessId = PsGetCurrentProcessId();UNREFERENCED_PARAMETER(RegistrationContext);if (OperationInformation->ObjectType != *IoFileObjectType){return OB_PREOP_SUCCESS;}// 过滤无效指针if (fileo->FileName.Buffer == NULL || !MmIsAddressValid(fileo->FileName.Buffer) || fileo->DeviceObject == NULL || !MmIsAddressValid(fileo->DeviceObject)){return OB_PREOP_SUCCESS;}// 过滤无效路径if (!_wcsicmp(fileo->FileName.Buffer, L"\\Endpoint") || !_wcsicmp(fileo->FileName.Buffer, L"?") || !_wcsicmp(fileo->FileName.Buffer, L"\\.\\.") || !_wcsicmp(fileo->FileName.Buffer, L"\\")){return OB_PREOP_SUCCESS;}// 将对象转为DOS路径RtlVolumeDeviceToDosName(fileo->DeviceObject, &DosName);DbgPrint("[LyShark] 进程PID = %ld | 文件路径 = %wZ%wZ \n", (ULONG64)CurrentProcessId, &DosName, &fileo->FileName);return OB_PREOP_SUCCESS;}VOID EnableObType(POBJECT_TYPE ObjectType){PMY_OBJECT_TYPE myobtype = (PMY_OBJECT_TYPE)ObjectType;myobtype->TypeInfo.SupportsObjectCallbacks = 1;}VOID UnDriver(PDRIVER_OBJECT driver){UNREFERENCED_PARAMETER(driver);ObUnRegisterCallbacks(obHandle);}NTSTATUS DriverEntry(IN PDRIVER_OBJECT Driver, PUNICODE_STRING RegistryPath){NTSTATUS status = STATUS_SUCCESS;PLDR_DATA ldr;DbgPrint("hello lyshark.com \n");OB_CALLBACK_REGISTRATION obRegFileCallBack;OB_OPERATION_REGISTRATION opRegFileCallBack;// enable IoFileObjectTypeEnableObType(*IoFileObjectType);// bypass MmVerifyCallbackFunctionldr = (PLDR_DATA)Driver->DriverSection;ldr->Flags |= 0x20;// 初始化回调memset(&obRegFileCallBack, 0, sizeof(obRegFileCallBack));obRegFileCallBack.Version = ObGetFilterVersion();obRegFileCallBack.OperationRegistrationCount = 1;obRegFileCallBack.RegistrationContext = NULL;RtlInitUnicodeString(&obRegFileCallBack.Altitude, L"321000");obRegFileCallBack.OperationRegistration = &opRegFileCallBack;memset(&opRegFileCallBack, 0, sizeof(opRegFileCallBack));opRegFileCallBack.ObjectType = IoFileObjectType;opRegFileCallBack.Operations = OB_OPERATION_HANDLE_CREATE | OB_OPERATION_HANDLE_DUPLICATE;opRegFileCallBack.PreOperation = (POB_PRE_OPERATION_CALLBACK)&LySharkFileObjectpreCall;status = ObRegisterCallbacks(&obRegFileCallBack, &obHandle);if (!NT_SUCCESS(status)){DbgPrint("注册回调错误 \n");status = STATUS_UNSUCCESSFUL;}UNREFERENCED_PARAMETER(RegistryPath);Driver->DriverUnload = &UnDriver;return status;}

运行这个驱动程序，当系统中有新文件被加载时则自动输出该文件所属进程PID以及该文件的详细路径。

至于如何阻止打开一个文件其实与《驱动开发：内核注册并监控对象回调》文章中使用的方法是一致的，首先判断OperationInformation->Operation是不是OB_OPERATION_HANDLE_CREATE或OB_OPERATION_HANDLE_DUPLICATE如果是，则直接设置Parameters->CreateHandleInformation.DesiredAccess为0直接拒绝加载。

// 文件回调OB_PREOP_CALLBACK_STATUS LySharkFileObjectpreCall(PVOID RegistrationContext, POB_PRE_OPERATION_INFORMATION OperationInformation){UNICODE_STRING DosName;PFILE_OBJECT fileo = OperationInformation->Object;HANDLE CurrentProcessId = PsGetCurrentProcessId();UNREFERENCED_PARAMETER(RegistrationContext);if (OperationInformation->ObjectType != *IoFileObjectType){return OB_PREOP_SUCCESS;}// 过滤无效指针if (fileo->FileName.Buffer == NULL || !MmIsAddressValid(fileo->FileName.Buffer) || fileo->DeviceObject == NULL || !MmIsAddressValid(fileo->DeviceObject)){return OB_PREOP_SUCCESS;}// 过滤无效路径if (!_wcsicmp(fileo->FileName.Buffer, L"\\Endpoint") || !_wcsicmp(fileo->FileName.Buffer, L"?") || !_wcsicmp(fileo->FileName.Buffer, L"\\.\\.") || !_wcsicmp(fileo->FileName.Buffer, L"\\")){return OB_PREOP_SUCCESS;}// 阻止打开lyshark_com.txt文本if (wcsstr(_wcslwr(fileo->FileName.Buffer), L"lyshark_com.txt")){if (OperationInformation->Operation == OB_OPERATION_HANDLE_CREATE){OperationInformation->Parameters->CreateHandleInformation.DesiredAccess = 0;}if (OperationInformation->Operation == OB_OPERATION_HANDLE_DUPLICATE){OperationInformation->Parameters->DuplicateHandleInformation.DesiredAccess = 0;}DbgPrint("[LyShark] 已拦截 lyshark_com 文件打开 \n");}return OB_PREOP_SUCCESS;}

运行修改后的驱动程序，然后尝试打开lyshark_com.txt则会提示系统找不到指定文件。

文章作者：lyshark (王瑞)
文章出处：https://www.cnblogs.com/LyShark/p/16821400.html
版权声明：本博客文章与代码均为学习时整理的笔记，文章 [均为原创] 作品，转载请 [添加出处] ，您添加出处是我创作的动力！

转载文章请遵守《中华人民共和国著作权法》相关法律规定或遵守《署名CC BY-ND 4.0国际》规范，合理合规携带原创出处转载，如果不携带文章出处，并恶意转载多篇原创文章被本人发现，本人保留起诉权！