驅動開發：內核註冊並監控對象回調

在筆者上一篇文章《驅動開發：內核枚舉進程與執行緒ObCall回調》簡單介紹了如何枚舉系統中已經存在的進程與執行緒回調，本章LyShark將通過對象回調實現對進程執行緒的句柄監控，在內核中提供了ObRegisterCallbacks回調，使用這個內核回調函數，可註冊一個對象回調，不過目前該函數只能監控進程與執行緒句柄操作，通過監控進程或執行緒句柄，可實現保護指定進程執行緒不被終止的目的。

由於目前對象回調只能監控進程與執行緒，而這個監控是通過ObjectType這麼一個成員控制的，如果成員是PsProcessType則代表監控進程，反之PsThreadType則是監控執行緒，無論監控進程還是執行緒都調用ObRegisterCallbacks這個函數來完成註冊。

函數ObRegisterCallbacks其微軟對他的定義是這樣的，用戶傳入OB_OPERATION_REGISTRATION結構，以及OB_CALLBACK_REGISTRATION回調結構，其中PreOperation則是傳入的回調函數，也是最重要的，其次是ObjectType指定成進程回調。

NTSTATUS ObRegisterCallbacks(
  [in]  POB_CALLBACK_REGISTRATION CallbackRegistration,
  [out] PVOID                     *RegistrationHandle
);

首先來實現一個檢測的案例，註冊一個進程回調對象MyLySharkComObjectCallBack，通過ObRegisterCallbacks註冊的回調只需要傳入一個填充好的OB_CALLBACK_REGISTRATION回調結構體，以及一個全局句柄即可，這個全局句柄的作用僅僅只是在程式結束時，調用ObUnRegisterCallbacks卸載監控而已，實現程式碼如下所示。

// 署名權
// right to sign one's name on a piece of work
// PowerBy: LyShark
// Email: [email protected]
#include <ntddk.h>
#include <ntstrsafe.h>

PVOID Globle_Object_Handle;

// 繞過簽名檢測
void BypassCheckSign(PDRIVER_OBJECT pDriverObj)
{
	typedef struct _LDR_DATA
	{
		struct _LIST_ENTRY InLoadOrderLinks;
		struct _LIST_ENTRY InMemoryOrderLinks;
		struct _LIST_ENTRY InInitializationOrderLinks;
		VOID*        DllBase;
		VOID*        EntryPoint;
		ULONG32      SizeOfImage;
		UINT8        _PADDING0_[0x4];
		struct _UNICODE_STRING FullDllName;
		struct _UNICODE_STRING BaseDllName;
		ULONG32      Flags;
	}LDR_DATA, *PLDR_DATA;

	PLDR_DATA ldr;
	ldr = (PLDR_DATA)(pDriverObj->DriverSection);
	ldr->Flags |= 0x20;
}

// 自定義回調
OB_PREOP_CALLBACK_STATUS MyLySharkComObjectCallBack(PVOID RegistrationContext, POB_PRE_OPERATION_INFORMATION OperationInformation)
{
	DbgPrint("[lyshark] 執行回調函數... \n");
	return STATUS_SUCCESS;
}

VOID UnDriver(PDRIVER_OBJECT driver)
{
	ObUnRegisterCallbacks(Globle_Object_Handle);
	DbgPrint("回調卸載完成... \n");
}

NTSTATUS DriverEntry(IN PDRIVER_OBJECT Driver, PUNICODE_STRING RegistryPath)
{
	DbgPrint("hello lyshark.com \n");

	BypassCheckSign(Driver);

	OB_OPERATION_REGISTRATION Base;                          // 回調函數結構體
	OB_CALLBACK_REGISTRATION CallbackReg;                    // 回調函數

	CallbackReg.RegistrationContext = NULL;                  // 註冊上下文(你回調函數返回參數)
	CallbackReg.Version = OB_FLT_REGISTRATION_VERSION;       // 註冊回調版本
	CallbackReg.OperationRegistration = &Base;               // 回調結構體
	CallbackReg.OperationRegistrationCount = 1;              // 操作計數(下鉤數量)

	RtlUnicodeStringInit(&CallbackReg.Altitude, L"600000");   // 長度
	Base.ObjectType = PsProcessType;                          // 進程操作類型.此處為進程操作
	Base.Operations = OB_OPERATION_HANDLE_CREATE;             // 操作句柄創建
	Base.PreOperation = MyLySharkComObjectCallBack;           // 你自己的回調函數
	Base.PostOperation = NULL;

	// 註冊回調
	if (ObRegisterCallbacks(&CallbackReg, &Globle_Object_Handle))
	{
		DbgPrint("[lyshark message] 回調註冊成功...");
	}
	Driver->DriverUnload = UnDriver;
	return STATUS_SUCCESS;
}

當驅動程式被載入以後，一旦有進程運行則會執行我們自己的MyLySharkComObjectCallBack回調，而在回調函數內則可以執行任意功能，運行如下所示。

如上所示只是演示基本的回調申請流程，回調函數通常需要包含兩個值，其一RegistrationContext用於標註上下文，其二POB_PRE_OPERATION_INFORMATION則用於標註進程或者執行緒創建的資訊結構體。

OB_PREOP_CALLBACK_STATUS MyLySharkComObjectCallBack(PVOID RegistrationContext, POB_PRE_OPERATION_INFORMATION OperationInformation)

那麼如何實現攔截進程啟動這個功能呢，我們可以在回調函數中寫入以下程式碼進行攔截。

CreateHandleInformation.DesiredAccess 將打開句柄的許可權清零
CreateHandleInformation.OriginalDesiredAccess 判斷是否終止

if (pOperationInformation->Operation == OB_OPERATION_HANDLE_CREATE)
{
	DbgPrint("lyshark.exe 進程打開 \n");
	pOperationInformation->Parameters->CreateHandleInformation.DesiredAccess=0;
	if ((pOperationInformation->Parameters->CreateHandleInformation.OriginalDesiredAccess & PROCESS_TERMINATE) == PROCESS_TERMINATE)
	{
		pOperationInformation->Parameters->CreateHandleInformation.DesiredAccess &= ~PROCESS_TERMINATE;
	}
}

攔截進程創建核心程式碼如下所示。

// 署名權
// right to sign one's name on a piece of work
// PowerBy: LyShark
// Email: [email protected]
#include <ntddk.h>
#include <ntstrsafe.h>

#define PROCESS_TERMINATE 0x1

// 導出兩個API
NTKERNELAPI PEPROCESS IoThreadToProcess(PETHREAD Thread);
NTKERNELAPI char* PsGetProcessImageFileName(PEPROCESS Process);

// 全局句柄
PVOID Globle_Object_Handle = NULL;

// 繞過簽名檢測
void BypassCheckSign(PDRIVER_OBJECT pDriverObj)
{
	typedef struct _LDR_DATA
	{
		struct _LIST_ENTRY InLoadOrderLinks;
		struct _LIST_ENTRY InMemoryOrderLinks;
		struct _LIST_ENTRY InInitializationOrderLinks;
		VOID*        DllBase;
		VOID*        EntryPoint;
		ULONG32      SizeOfImage;
		UINT8        _PADDING0_[0x4];
		struct _UNICODE_STRING FullDllName;
		struct _UNICODE_STRING BaseDllName;
		ULONG32      Flags;
	}LDR_DATA, *PLDR_DATA;

	PLDR_DATA ldr;
	ldr = (PLDR_DATA)(pDriverObj->DriverSection);
	ldr->Flags |= 0x20;
}

// 判斷是否是需要保護的進程
BOOLEAN CheckProcess(PEPROCESS eprocess)
{
	char *Name = PsGetProcessImageFileName(eprocess);
	if (!_stricmp("lyshark.exe", Name))
		return TRUE;
	else
		return FALSE;
}

// 進程回調
OB_PREOP_CALLBACK_STATUS MyLySharkProcessObjectCallBack(PVOID RegistrationContext, POB_PRE_OPERATION_INFORMATION pOperationInformation)
{
	HANDLE pid;

	// 只取出進程回調
	if (pOperationInformation->ObjectType != *PsProcessType)
	{
		return OB_PREOP_SUCCESS;
	}

	// 得到所有進程的ID
	pid = PsGetProcessId((PEPROCESS)pOperationInformation->Object);
	// DbgPrint("進程PID= %ld \n", pid);

	UNREFERENCED_PARAMETER(RegistrationContext);

	// 驗證是否是需要的進程
	if (CheckProcess((PEPROCESS)pOperationInformation->Object))
	{
		// 創建句柄
		if (pOperationInformation->Operation == OB_OPERATION_HANDLE_CREATE)
		{
			DbgPrint("lyshark.exe 進程打開事件 \n");
			pOperationInformation->Parameters->CreateHandleInformation.DesiredAccess=0;
			if ((pOperationInformation->Parameters->CreateHandleInformation.OriginalDesiredAccess & PROCESS_TERMINATE) == PROCESS_TERMINATE)
			{
				DbgPrint("[LyShark Message] 攔截進程打開 \n");
				pOperationInformation->Parameters->CreateHandleInformation.DesiredAccess &= ~PROCESS_TERMINATE;
			}
		}
		// 複製句柄
		if (pOperationInformation->Operation == OB_OPERATION_HANDLE_DUPLICATE)
		{
			DbgPrint("lyshark.exe 進程被關閉 \n");
			pOperationInformation->Parameters->DuplicateHandleInformation.DesiredAccess=0;
			if ((pOperationInformation->Parameters->DuplicateHandleInformation.OriginalDesiredAccess & PROCESS_TERMINATE) == PROCESS_TERMINATE)
			{
				pOperationInformation->Parameters->DuplicateHandleInformation.DesiredAccess &= ~PROCESS_TERMINATE;
			}
		}
	}
	return OB_PREOP_SUCCESS;
}

VOID UnDriver(PDRIVER_OBJECT driver)
{
	ObUnRegisterCallbacks(Globle_Object_Handle);
	DbgPrint("回調卸載完成... \n");
}

NTSTATUS DriverEntry(IN PDRIVER_OBJECT Driver, PUNICODE_STRING RegistryPath)
{
	DbgPrint("hello lyshark.com \n");

	BypassCheckSign(Driver);

	OB_OPERATION_REGISTRATION ob_process_callback;
	OB_CALLBACK_REGISTRATION op_process_operation;

	memset(&ob_process_callback, 0, sizeof(ob_process_callback));
	ob_process_callback.ObjectType = PsProcessType;
	ob_process_callback.Operations = OB_OPERATION_HANDLE_CREATE | OB_OPERATION_HANDLE_DUPLICATE;
	ob_process_callback.PreOperation = MyLySharkProcessObjectCallBack;
	ob_process_callback.PostOperation = NULL;

	RtlUnicodeStringInit(&op_process_operation.Altitude, L"600000");
	op_process_operation.RegistrationContext = NULL;
	op_process_operation.Version = OB_FLT_REGISTRATION_VERSION;
	op_process_operation.OperationRegistration = &ob_process_callback;
	op_process_operation.OperationRegistrationCount = 1;

	// 註冊進程回調
	if (ObRegisterCallbacks(&op_process_operation, &Globle_Object_Handle))
	{
		DbgPrint("進程回調註冊成功...");
	}

	Driver->DriverUnload = UnDriver;
	return STATUS_SUCCESS;
}

載入這個驅動，當有進程被創建時，則首先判斷是否是lyshark.exe如果是則直接禁止打開，也就是終止掉。

同理進程可以被攔截，那麼如果增加更多的過濾條件，則執行緒同樣可以被攔截，攔截執行緒程式碼如下所示。

// 署名權
// right to sign one's name on a piece of work
// PowerBy: LyShark
// Email: [email protected]
#include <ntddk.h>
#include <ntstrsafe.h>

#define THREAD_TERMINATE2 0x1

// 導出兩個API
NTKERNELAPI PEPROCESS IoThreadToProcess(PETHREAD Thread);
NTKERNELAPI char* PsGetProcessImageFileName(PEPROCESS Process);

// 全局句柄
PVOID Globle_Object_Handle = NULL;

// 繞過簽名檢測
void BypassCheckSign(PDRIVER_OBJECT pDriverObj)
{
	typedef struct _LDR_DATA
	{
		struct _LIST_ENTRY InLoadOrderLinks;
		struct _LIST_ENTRY InMemoryOrderLinks;
		struct _LIST_ENTRY InInitializationOrderLinks;
		VOID*        DllBase;
		VOID*        EntryPoint;
		ULONG32      SizeOfImage;
		UINT8        _PADDING0_[0x4];
		struct _UNICODE_STRING FullDllName;
		struct _UNICODE_STRING BaseDllName;
		ULONG32      Flags;
	}LDR_DATA, *PLDR_DATA;

	PLDR_DATA ldr;
	ldr = (PLDR_DATA)(pDriverObj->DriverSection);
	ldr->Flags |= 0x20;
}

// 判斷是否是需要保護的進程
BOOLEAN CheckProcess(PEPROCESS eprocess)
{
	char *Name = PsGetProcessImageFileName(eprocess);
	if (!_stricmp("lyshark.exe", Name))
		return TRUE;
	else
		return FALSE;
}

// 執行緒回調
OB_PREOP_CALLBACK_STATUS MyThreadObjectCallBack(PVOID RegistrationContext, POB_PRE_OPERATION_INFORMATION pOperationInformation)
{
	PEPROCESS ep;
	PETHREAD et;
	HANDLE pid;

	// 執行緒過濾
	if (pOperationInformation->ObjectType != *PsThreadType)
	{
		return OB_PREOP_SUCCESS;
	}

	et = (PETHREAD)pOperationInformation->Object;
	ep = IoThreadToProcess(et);
	pid = PsGetProcessId(ep);

	// DbgPrint("執行緒PID= %ld | TID= %ld \n", pid, PsGetThreadId(et));
	UNREFERENCED_PARAMETER(RegistrationContext);

	if (CheckProcess(ep))
	{
		if (pOperationInformation->Operation == OB_OPERATION_HANDLE_CREATE)
		{
			pOperationInformation->Parameters->CreateHandleInformation.DesiredAccess=0;
			if ((pOperationInformation->Parameters->CreateHandleInformation.OriginalDesiredAccess & THREAD_TERMINATE2) == THREAD_TERMINATE2)
			{
				DbgPrint("[LyShark] 攔截lyshark.exe進程內 %d 執行緒創建 \n", PsGetThreadId(et));
				pOperationInformation->Parameters->CreateHandleInformation.DesiredAccess &= ~THREAD_TERMINATE2;
			}
		}
		if (pOperationInformation->Operation == OB_OPERATION_HANDLE_DUPLICATE)
		{
			pOperationInformation->Parameters->DuplicateHandleInformation.DesiredAccess=0;
			if ((pOperationInformation->Parameters->DuplicateHandleInformation.OriginalDesiredAccess & THREAD_TERMINATE2) == THREAD_TERMINATE2)
			{
				pOperationInformation->Parameters->DuplicateHandleInformation.DesiredAccess &= ~THREAD_TERMINATE2;
			}
		}
	}
	return OB_PREOP_SUCCESS;
}

VOID UnDriver(PDRIVER_OBJECT driver)
{
	ObUnRegisterCallbacks(Globle_Object_Handle);
	DbgPrint("回調卸載完成... \n");
}

NTSTATUS DriverEntry(IN PDRIVER_OBJECT Driver, PUNICODE_STRING RegistryPath)
{
	DbgPrint("hello lyshark.com \n");

	BypassCheckSign(Driver);

	OB_OPERATION_REGISTRATION ob_thread_callback;
	OB_CALLBACK_REGISTRATION op_thread_operation;

	memset(&ob_thread_callback, 0, sizeof(ob_thread_callback));
	ob_thread_callback.ObjectType = PsThreadType;
	ob_thread_callback.Operations = OB_OPERATION_HANDLE_CREATE | OB_OPERATION_HANDLE_DUPLICATE;
	ob_thread_callback.PreOperation = MyThreadObjectCallBack;
	ob_thread_callback.PostOperation = NULL;

	RtlUnicodeStringInit(&op_thread_operation.Altitude, L"600001");
	op_thread_operation.RegistrationContext = NULL;
	op_thread_operation.Version = OB_FLT_REGISTRATION_VERSION;
	op_thread_operation.OperationRegistration = &ob_thread_callback;
	op_thread_operation.OperationRegistrationCount = 1;

	// 註冊進程回調
	if (ObRegisterCallbacks(&op_thread_operation, &Globle_Object_Handle))
	{
		DbgPrint("進程回調註冊成功...");
	}

	Driver->DriverUnload = UnDriver;
	return STATUS_SUCCESS;
}

這段驅動載入後，如果有新執行緒被創建，則會被攔截並列印輸出，效果圖如下。

參考文獻

//www.cnblogs.com/ciyze0101/p/5468175.html

Tags: Windows 內核安全開發 Windows 內核驅動開發