驱动开发：通过应用堆实现多次通信

在前面的文章《运用MDL映射实现多次通信》LyShark教大家使用MDL的方式灵活的实现了内核态多次输出结构体的效果，但是此种方法并不推荐大家使用原因很简单首先内核空间比较宝贵，其次内核里面不能分配太大且每次传出的结构体最大不能超过1024个，而最终这些内存由于无法得到更好的释放从而导致坏堆的产生，这样的程序显然是无法在生产环境中使用的，如下LyShark将教大家通过在应用层申请空间来实现同等效果，此类传递方式也是多数ARK反内核工具中最常采用的一种。

与MDL映射相反，MDL多数处理流程在内核代码中，而应用层开堆复杂代码则在应用层，但内核层中同样还是需要使用指针，只是这里的指针仅仅只是保留基本要素即可，通过EnumProcess()模拟枚举进程操作，传入的是PPROCESS_INFO进程指针转换，将数据传入到PPROCESS_INFO直接返回进程计数器即可。

// -------------------------------------------------
// R3传输结构体
// -------------------------------------------------

// 进程指针转换
typedef struct
{
  DWORD PID;
  DWORD PPID;
}PROCESS_INFO, *PPROCESS_INFO;

// 数据存储指针
typedef struct
{
  ULONG_PTR nSize;
  PVOID BufferPtr;
}BufferPointer, *pBufferPointer;

// 模拟进程枚举
ULONG EnumProcess(PPROCESS_INFO pBuffer)
{
  ULONG nCount = 0;

  for (size_t i = 0; i < 10; i++)
  {
    pBuffer[i].PID = nCount * 2;
    pBuffer[i].PPID = nCount * 4;

    nCount = nCount + 1;
  }
  return nCount;
}

内核层核心代码： 内核代码中是如何通信的，首先从用户态接收pIoBuffer到分配的缓冲区数据，并转换为pBufferPointer结构，ProbeForWrite用于检查地址是否可写入，接着会调用EnumProcess()注意传入的其实是应用层的指针，枚举进程结束后，将进程数量nCount通过*(PULONG)pIrp->AssociatedIrp.SystemBuffer = (ULONG)nCount回传给应用层，至此内核中仅仅回传了一个长度，其他的都写入到了应用层中。

pBufferPointer pinp = (pBufferPointer)pIoBuffer;

__try
{
  DbgPrint("缓冲区长度: %d \n", pinp->nSize);
  DbgPrint("缓冲区基地址: %p \n", pinp->BufferPtr);

  // 检查地址是否可写入
  ProbeForWrite(pinp->BufferPtr, pinp->nSize, 1);

  ULONG nCount = EnumProcess((PPROCESS_INFO)pinp->BufferPtr);
  DbgPrint("进程计数 = %d \n", nCount);
  if (nCount > 0)
  {
    // 将进程数返回给用户
    *(PULONG)pIrp->AssociatedIrp.SystemBuffer = (ULONG)nCount;
    status = STATUS_SUCCESS;
  }
}
__except (1)
{
  status = GetExceptionCode();
  DbgPrint("IOCTL_GET_EPROCESS %x \n", status);
}

// 返回通信状态
status = STATUS_SUCCESS;
break;

应用层核心代码： 通信的重点在于应用层，首先定义BufferPointer用于存放缓冲区头部指针，定义PPROCESS_INFO则是用于后期将数据放入该容器内，函数HeapAlloc分配一段堆空间，并HEAP_ZERO_MEMORY将该堆空间全部填空，将这一段初始化后的空间放入到pInput.BufferPtr缓冲区内，并计算出长度放入到pInput.nSize缓冲区内，一切准备就绪之后，再通过DriveControl.IoControl将BufferPointer结构传输至内核中，而bRet则是用于接收返回长度的变量。

当收到数据后，通过(PPROCESS_INFO)pInput.BufferPtr强制转换为指针类型，并依次pProcessInfo[i]读出每一个节点的元素，最后是调用HeapFree释放掉这段堆空间。至于输出就很简单了vectorProcess[x].PID循环容器元素即可。

// 应用层数据结构体数据
BOOL bRet = FALSE;
BufferPointer pInput = { 0 };
PPROCESS_INFO pProcessInfo = NULL;

// 分配堆空间
pInput.BufferPtr = (PVOID)HeapAlloc(GetProcessHeap(), HEAP_ZERO_MEMORY, sizeof(PROCESS_INFO) * 1000);
pInput.nSize = sizeof(PROCESS_INFO) * 1000;

ULONG nRet = 0;

if (pInput.BufferPtr)
{
  bRet = DriveControl.IoControl(IOCTL_IO_R3StructAll, &pInput, sizeof(BufferPointer), &nRet, sizeof(ULONG), 0);
}

std::cout << "返回结构体数量: " << nRet << std::endl;

if (bRet && nRet > 0)
{
  pProcessInfo = (PPROCESS_INFO)pInput.BufferPtr;
  std::vector<PROCESS_INFO> vectorProcess;

  for (ULONG i = 0; i < nRet; i++)
  {
    vectorProcess.push_back(pProcessInfo[i]);
  }

  // 释放空间
  bRet = HeapFree(GetProcessHeap(), 0, pInput.BufferPtr);
  std::cout << "释放状态: " << bRet << std::endl;

  // 输出容器内的进程ID列表
  for (int x = 0; x < nRet; x++)
  {
    std::cout << "PID: " << vectorProcess[x].PID << " PPID: " << vectorProcess[x].PPID << std::endl;
  }
}

// 关闭符号链接句柄
CloseHandle(DriveControl.m_hDriver);

如上就是内核层与应用层的部分代码功能分析，接下来我将完整代码分享出来，大家可以自行测试效果。

驱动程序WinDDK.sys完整代码；

#define _CRT_SECURE_NO_WARNINGS
#include <ntifs.h>
#include <windef.h>

// 定义符号链接，一般来说修改为驱动的名字即可
#define DEVICE_NAME        L"\\Device\\WinDDK"
#define LINK_NAME          L"\\DosDevices\\WinDDK"
#define LINK_GLOBAL_NAME   L"\\DosDevices\\Global\\WinDDK"

// 定义驱动功能号和名字，提供接口给应用程序调用
#define IOCTL_IO_R3StructAll    CTL_CODE(FILE_DEVICE_UNKNOWN, 0x806, METHOD_BUFFERED, FILE_ANY_ACCESS)

// 保存一段非分页内存,用于给全局变量使用
#define FILE_DEVICE_EXTENSION 4096

// -------------------------------------------------
// R3传输结构体
// -------------------------------------------------

// 进程指针转换
typedef struct
{
	DWORD PID;
	DWORD PPID;
}PROCESS_INFO, *PPROCESS_INFO;

// 数据存储指针
typedef struct
{
	ULONG_PTR nSize;
	PVOID BufferPtr;
}BufferPointer, *pBufferPointer;

// 模拟进程枚举
ULONG EnumProcess(PPROCESS_INFO pBuffer)
{
	ULONG nCount = 0;

	for (size_t i = 0; i < 10; i++)
	{
		pBuffer[i].PID = nCount * 2;
		pBuffer[i].PPID = nCount * 4;

		nCount = nCount + 1;
	}
	return nCount;
}

// 驱动绑定默认派遣函数
NTSTATUS DefaultDispatch(PDEVICE_OBJECT _pDeviceObject, PIRP _pIrp)
{
	_pIrp->IoStatus.Status = STATUS_NOT_SUPPORTED;
	_pIrp->IoStatus.Information = 0;
	IoCompleteRequest(_pIrp, IO_NO_INCREMENT);
	return _pIrp->IoStatus.Status;
}

// 驱动卸载的处理例程
VOID DriverUnload(PDRIVER_OBJECT pDriverObj)
{
	if (pDriverObj->DeviceObject)
	{
		UNICODE_STRING strLink;

		// 删除符号连接和设备
		RtlInitUnicodeString(&strLink, LINK_NAME);
		IoDeleteSymbolicLink(&strLink);
		IoDeleteDevice(pDriverObj->DeviceObject);
		DbgPrint("[kernel] # 驱动已卸载 \n");
	}
}

// IRP_MJ_CREATE 对应的处理例程，一般不用管它
NTSTATUS DispatchCreate(PDEVICE_OBJECT pDevObj, PIRP pIrp)
{
	DbgPrint("[kernel] # 驱动处理例程载入 \n");
	pIrp->IoStatus.Status = STATUS_SUCCESS;
	pIrp->IoStatus.Information = 0;
	IoCompleteRequest(pIrp, IO_NO_INCREMENT);
	return STATUS_SUCCESS;
}

// IRP_MJ_CLOSE 对应的处理例程，一般不用管它
NTSTATUS DispatchClose(PDEVICE_OBJECT pDevObj, PIRP pIrp)
{
	DbgPrint("[kernel] # 关闭派遣 \n");
	pIrp->IoStatus.Status = STATUS_SUCCESS;
	pIrp->IoStatus.Information = 0;
	IoCompleteRequest(pIrp, IO_NO_INCREMENT);
	return STATUS_SUCCESS;
}

// IRP_MJ_DEVICE_CONTROL 对应的处理例程，驱动最重要的函数
NTSTATUS DispatchIoctl(PDEVICE_OBJECT pDevObj, PIRP pIrp)
{
	NTSTATUS status = STATUS_INVALID_DEVICE_REQUEST;
	PIO_STACK_LOCATION pIrpStack;
	ULONG uIoControlCode;
	PVOID pIoBuffer;
	ULONG uInSize;
	ULONG uOutSize;

	// 获得IRP里的关键数据
	pIrpStack = IoGetCurrentIrpStackLocation(pIrp);

	// 获取控制码
	uIoControlCode = pIrpStack->Parameters.DeviceIoControl.IoControlCode;

	// 输入和输出的缓冲区（DeviceIoControl的InBuffer和OutBuffer都是它）
	pIoBuffer = pIrp->AssociatedIrp.SystemBuffer;

	// EXE发送传入数据的BUFFER长度（DeviceIoControl的nInBufferSize）
	uInSize = pIrpStack->Parameters.DeviceIoControl.InputBufferLength;

	// EXE接收传出数据的BUFFER长度（DeviceIoControl的nOutBufferSize）
	uOutSize = pIrpStack->Parameters.DeviceIoControl.OutputBufferLength;

	// 对不同控制信号的处理流程
	switch (uIoControlCode)
	{
	// 测试R3传输多次结构体
	case IOCTL_IO_R3StructAll:
	{
		pBufferPointer pinp = (pBufferPointer)pIoBuffer;

		__try
		{
			DbgPrint("[lyshark] 缓冲区长度: %d \n", pinp->nSize);
			DbgPrint("[lyshark] 缓冲区基地址: %p \n", pinp->BufferPtr);

			// 检查地址是否可写入
			ProbeForWrite(pinp->BufferPtr, pinp->nSize, 1);

			ULONG nCount = EnumProcess((PPROCESS_INFO)pinp->BufferPtr);
			DbgPrint("[lyshark.com] 进程计数 = %d \n", nCount);
			if (nCount > 0)
			{
				// 将进程数返回给用户
				*(PULONG)pIrp->AssociatedIrp.SystemBuffer = (ULONG)nCount;
				status = STATUS_SUCCESS;
			}
		}
		__except (1)
		{
			status = GetExceptionCode();
			DbgPrint("IOCTL_GET_EPROCESS %x \n", status);
		}

		// 返回通信状态
		status = STATUS_SUCCESS;
		break;
	}
	}

	// 设定DeviceIoControl的*lpBytesReturned的值（如果通信失败则返回0长度）
	if (status == STATUS_SUCCESS)
	{
		pIrp->IoStatus.Information = uOutSize;
	}
	else
	{
		pIrp->IoStatus.Information = 0;
	}

	// 设定DeviceIoControl的返回值是成功还是失败
	pIrp->IoStatus.Status = status;
	IoCompleteRequest(pIrp, IO_NO_INCREMENT);
	return status;
}

// 驱动的初始化工作
NTSTATUS DriverEntry(PDRIVER_OBJECT pDriverObj, PUNICODE_STRING pRegistryString)
{
	NTSTATUS status = STATUS_SUCCESS;
	UNICODE_STRING ustrLinkName;
	UNICODE_STRING ustrDevName;
	PDEVICE_OBJECT pDevObj;

	// 初始化其他派遣
	for (ULONG i = 0; i < IRP_MJ_MAXIMUM_FUNCTION; i++)
	{
		// DbgPrint("初始化派遣: %d \n", i);
		pDriverObj->MajorFunction[i] = DefaultDispatch;
	}

	// 设置分发函数和卸载例程
	pDriverObj->MajorFunction[IRP_MJ_CREATE] = DispatchCreate;
	pDriverObj->MajorFunction[IRP_MJ_CLOSE] = DispatchClose;
	pDriverObj->MajorFunction[IRP_MJ_DEVICE_CONTROL] = DispatchIoctl;
	pDriverObj->DriverUnload = DriverUnload;

	// 创建一个设备
	RtlInitUnicodeString(&ustrDevName, DEVICE_NAME);

	// FILE_DEVICE_EXTENSION 创建设备时，指定设备扩展内存的大小，传一个值进去，就会给设备分配一块非页面内存。
	status = IoCreateDevice(pDriverObj, sizeof(FILE_DEVICE_EXTENSION), &ustrDevName, FILE_DEVICE_UNKNOWN, 0, FALSE, &pDevObj);
	if (!NT_SUCCESS(status))
	{
		return status;
	}

	// 判断支持的WDM版本，其实这个已经不需要了，纯属WIN9X和WINNT并存时代的残留物
	if (IoIsWdmVersionAvailable(1, 0x10))
	{
		RtlInitUnicodeString(&ustrLinkName, LINK_GLOBAL_NAME);
	}
	else
	{
		RtlInitUnicodeString(&ustrLinkName, LINK_NAME);
	}

	// 创建符号连接
	status = IoCreateSymbolicLink(&ustrLinkName, &ustrDevName);
	if (!NT_SUCCESS(status))
	{
		DbgPrint("创建符号链接失败 \n");
		IoDeleteDevice(pDevObj);
		return status;
	}
	DbgPrint("[hello LyShark.com] # 驱动初始化完毕 \n");

	// 返回加载驱动的状态（如果返回失败，驱动讲被清除出内核空间）
	return STATUS_SUCCESS;
}

应用层客户端程序lyshark.exe完整代码；

#include <iostream>
#include <Windows.h>
#include <vector>

#pragma comment(lib,"user32.lib")
#pragma comment(lib,"advapi32.lib")

// 定义驱动功能号和名字，提供接口给应用程序调用
#define IOCTL_IO_R3StructAll    0x806

class cDrvCtrl
{
public:
	cDrvCtrl()
	{
		m_pSysPath = NULL;
		m_pServiceName = NULL;
		m_pDisplayName = NULL;
		m_hSCManager = NULL;
		m_hService = NULL;
		m_hDriver = INVALID_HANDLE_VALUE;
	}
	~cDrvCtrl()
	{
		CloseServiceHandle(m_hService);
		CloseServiceHandle(m_hSCManager);
		CloseHandle(m_hDriver);
	}

	// 安装驱动
	BOOL Install(PCHAR pSysPath, PCHAR pServiceName, PCHAR pDisplayName)
	{
		m_pSysPath = pSysPath;
		m_pServiceName = pServiceName;
		m_pDisplayName = pDisplayName;
		m_hSCManager = OpenSCManagerA(NULL, NULL, SC_MANAGER_ALL_ACCESS);
		if (NULL == m_hSCManager)
		{
			m_dwLastError = GetLastError();
			return FALSE;
		}
		m_hService = CreateServiceA(m_hSCManager, m_pServiceName, m_pDisplayName,
			SERVICE_ALL_ACCESS, SERVICE_KERNEL_DRIVER, SERVICE_DEMAND_START, SERVICE_ERROR_NORMAL,
			m_pSysPath, NULL, NULL, NULL, NULL, NULL);
		if (NULL == m_hService)
		{
			m_dwLastError = GetLastError();
			if (ERROR_SERVICE_EXISTS == m_dwLastError)
			{
				m_hService = OpenServiceA(m_hSCManager, m_pServiceName, SERVICE_ALL_ACCESS);
				if (NULL == m_hService)
				{
					CloseServiceHandle(m_hSCManager);
					return FALSE;
				}
			}
			else
			{
				CloseServiceHandle(m_hSCManager);
				return FALSE;
			}
		}
		return TRUE;
	}

	// 启动驱动
	BOOL Start()
	{
		if (!StartServiceA(m_hService, NULL, NULL))
		{
			m_dwLastError = GetLastError();
			return FALSE;
		}
		return TRUE;
	}

	// 关闭驱动
	BOOL Stop()
	{
		SERVICE_STATUS ss;
		GetSvcHandle(m_pServiceName);
		if (!ControlService(m_hService, SERVICE_CONTROL_STOP, &ss))
		{
			m_dwLastError = GetLastError();
			return FALSE;
		}
		return TRUE;
	}

	// 移除驱动
	BOOL Remove()
	{
		GetSvcHandle(m_pServiceName);
		if (!DeleteService(m_hService))
		{
			m_dwLastError = GetLastError();
			return FALSE;
		}
		return TRUE;
	}

	// 打开驱动
	BOOL Open(PCHAR pLinkName)
	{
		if (m_hDriver != INVALID_HANDLE_VALUE)
			return TRUE;
		m_hDriver = CreateFileA(pLinkName, GENERIC_READ | GENERIC_WRITE, 0, 0, OPEN_EXISTING, FILE_ATTRIBUTE_NORMAL, 0);
		if (m_hDriver != INVALID_HANDLE_VALUE)
			return TRUE;
		else
			return FALSE;
	}

	// 发送控制信号
	BOOL IoControl(DWORD dwIoCode, PVOID InBuff, DWORD InBuffLen, PVOID OutBuff, DWORD OutBuffLen, DWORD *RealRetBytes)
	{
		DWORD dw;
		BOOL b = DeviceIoControl(m_hDriver, CTL_CODE_GEN(dwIoCode), InBuff, InBuffLen, OutBuff, OutBuffLen, &dw, NULL);
		if (RealRetBytes)
			*RealRetBytes = dw;
		return b;
	}
private:

	// 获取服务句柄
	BOOL GetSvcHandle(PCHAR pServiceName)
	{
		m_pServiceName = pServiceName;
		m_hSCManager = OpenSCManagerA(NULL, NULL, SC_MANAGER_ALL_ACCESS);
		if (NULL == m_hSCManager)
		{
			m_dwLastError = GetLastError();
			return FALSE;
		}
		m_hService = OpenServiceA(m_hSCManager, m_pServiceName, SERVICE_ALL_ACCESS);
		if (NULL == m_hService)
		{
			CloseServiceHandle(m_hSCManager);
			return FALSE;
		}
		else
		{
			return TRUE;
		}
	}

	// 获取控制信号对应字符串
	DWORD CTL_CODE_GEN(DWORD lngFunction)
	{
		return (FILE_DEVICE_UNKNOWN * 65536) | (FILE_ANY_ACCESS * 16384) | (lngFunction * 4) | METHOD_BUFFERED;
	}

public:
	DWORD m_dwLastError;
	PCHAR m_pSysPath;
	PCHAR m_pServiceName;
	PCHAR m_pDisplayName;
	HANDLE m_hDriver;
	SC_HANDLE m_hSCManager;
	SC_HANDLE m_hService;
};

void GetAppPath(char *szCurFile)
{
	GetModuleFileNameA(0, szCurFile, MAX_PATH);
	for (SIZE_T i = strlen(szCurFile) - 1; i >= 0; i--)
	{
		if (szCurFile[i] == '\\')
		{
			szCurFile[i + 1] = '\0';
			break;
		}
	}
}

// -------------------------------------------------
// R3数据传递变量
// -------------------------------------------------
// 进程指针转换
typedef struct
{
	DWORD PID;
	DWORD PPID;
}PROCESS_INFO, *PPROCESS_INFO;

// 数据存储指针
typedef struct
{
	ULONG_PTR nSize;
	PVOID BufferPtr;
}BufferPointer, *pBufferPointer;

int main(int argc, char *argv[])
{
	cDrvCtrl DriveControl;

	// 设置驱动名称
	char szSysFile[MAX_PATH] = { 0 };
	char szSvcLnkName[] = "WinDDK";;
	GetAppPath(szSysFile);
	strcat(szSysFile, "WinDDK.sys");

	// 安装并启动驱动
	DriveControl.Install(szSysFile, szSvcLnkName, szSvcLnkName);
	DriveControl.Start();

	// 打开驱动的符号链接
	DriveControl.Open("\\\\.\\WinDDK");

	// 应用层数据结构体数据
	BOOL bRet = FALSE;
	BufferPointer pInput = { 0 };
	PPROCESS_INFO pProcessInfo = NULL;

	// 分配堆空间
	pInput.BufferPtr = (PVOID)HeapAlloc(GetProcessHeap(), HEAP_ZERO_MEMORY, sizeof(PROCESS_INFO) * 1000);
	pInput.nSize = sizeof(PROCESS_INFO) * 1000;

	ULONG nRet = 0;

	if (pInput.BufferPtr)
	{
		bRet = DriveControl.IoControl(IOCTL_IO_R3StructAll, &pInput, sizeof(BufferPointer), &nRet, sizeof(ULONG), 0);
	}

	std::cout << "[LyShark.com] 返回结构体数量: " << nRet << std::endl;

	if (bRet && nRet > 0)
	{
		pProcessInfo = (PPROCESS_INFO)pInput.BufferPtr;
		std::vector<PROCESS_INFO> vectorProcess;

		for (ULONG i = 0; i < nRet; i++)
		{
			vectorProcess.push_back(pProcessInfo[i]);
		}

		// 释放空间
		bRet = HeapFree(GetProcessHeap(), 0, pInput.BufferPtr);
		std::cout << "释放状态: " << bRet << std::endl;

		// 输出容器内的进程ID列表
		for (int x = 0; x < nRet; x++)
		{
			std::cout << "PID: " << vectorProcess[x].PID << " PPID: " << vectorProcess[x].PPID << std::endl;
		}
	}

	// 关闭符号链接句柄
	CloseHandle(DriveControl.m_hDriver);

	// 停止并卸载驱动
	DriveControl.Stop();
	DriveControl.Remove();

	system("pause");
	return 0;
}

手动编译这两个程序，将驱动签名后以管理员身份运行lyshark.exe客户端，此时屏幕中即可看到滚动输出效果，如此一来就实现了循环传递参数的目的。