您当前的位置 >> 首页     

再谈进程与端口的映射

/ns/wz/comp/data/20020821020435.htm



再谈进程与端口的映射(WSS-Articles-02003)
Author : ilsy
Email : ilsy@whitecell.org
HomePage: http://www.whitecell.org


--------------------------------------------------------------------------------

类 别：安全
关键字：进程 PDE PTE 分页 内核对象 线性地址 物理地址


关于进程与端口映射的文章已经有很多了,我把我对fport的分析也写出来,让大家 知道fport是如何工作的.
fport.exe是由foundstone team出品的免费软件,可以列出系统中所有开放的端口都是 由那些进程打开的.而下
面所描述的方法是基于fport v1.33的,如果和你机器上的fport有出入,请检查fport版 本.

首先,它检测当前用户是否拥有管理员权限(通过读取当前进程的令牌可知当前用 户是否具有管理权限,请参考
相关历程),如果没有,打印一句提示后退出,然后设置当前进程的令牌,接着,用 ZwOpenSection函数打开内核对象
\Device\PhysicalMemory,这个对象用于对系统物理内存的访问.ZwOpenSection函数的 原型如下:

NTSYSAPI
NTSTSTUS
NTAPI
ZwOpenSection(
Out PHANDLE sectionHandle;
IN ACCESS_MASK DesiredAccess;
IN POBJECT_ATTRIBUTES ObjectAttributes
};
(见ntddk.h)

第一个参数得到函数执行成功后的句柄
第二个参数DesiredAccess为一个常数,可以是下列值:
#define SECTION_QUERY 0x0001
#define SECTION_MAP_WRITE 0x0002
#define SECTION_MAP_READ 0x0004
#define SECTION_MAP_EXECUTE 0x0008
#define SECTION_EXTEND_SIZE 0x0010

#define SECTION_ALL_ACCESS (STANDARD_RIGHTS_REQUIRED|SECTION_QUERY|\
SECTION_MAP_WRITE | \
SECTION_MAP_READ | \
SECTION_MAP_EXECUTE | \
SECTION_EXTEND_SIZE)
(见ntddk.h)
第三个参数是一个结构,包含要打开的对象类型等信息,结构定义如下:
typedef struct _OBJECT_ATTRIBUTES {
ULONG Length;
HANDLE RootDirectory;
PUNICODE_STRING ObjectName;
ULONG Attributes;
PVOID SecurityDescriptor; // Points to type SECURITY_DESCRIPTOR
PVOID SecurityQualityOfService; // Points to type SECURITY_QUALITY_OF_SERVICE
} OBJECT_ATTRIBUTES;
typedef OBJECT_ATTRIBUTES *POBJECT_ATTRIBUTES;
(见ntdef.h)
对于这个结构的初始化用一个宏完成:
#define InitializeObjectAttributes( p, n, a, r, s ) { \
(p)->Length = sizeof( OBJECT_ATTRIBUTES ); \
(p)->RootDirectory = r; \
(p)->Attributes = a; \
(p)->ObjectName = n; \
(p)->SecurityDescriptor = s; \
(p)->SecurityQualityOfService = NULL; \
}
(见ntdef.h)
那么,打开内核对象\Device\PhysicalMemory的语句如下:
WCHAR PhysmemName[] = L"\\Device\\PhysicalMemory";
void * pMapPhysicalMemory;
HANDLE pHandle;

bool OpenPhysicalMemory()
{
NTSTATUS status;
UNICODE_STRING physmemString;
OBJECT_ATTRIBUTES attributes;
RtlInitUnicodeString( &physmemString, PhysmemName ); //初始化 Unicode字符串,函数原型见ntddk.h
InitializeObjectAttributes( &attributes, &physmemString,
OBJ_CASE_INSENSITIVE, NULL, NULL ); // 初始化OBJECT_ATTRIBUTES结构
status = ZwOpenSection(pHandle, SECTION_MAP_READ, &attributes ); // 打开内核对象\Device\PhysicalMemory,获得句柄
if( !NT_SUCCESS( status ))
return false;
pMapPhysicalMemory=MapViewOfFile(pHandle,FILE_MAP_READ,
0,0x30000,0x1000);
//从内存地址0x30000开始映射0x1000个字节
if( GetLastError()!=0)
return false;
return true;
}

为什么要从0x30000开始映射呢,是这样,我们知道,在Windows NT/2000下,系统分 为内核模式和用户模式,也就是我们
所说的Ring0和Ring3,在Windows NT/2000下,我们所能够看到的进程都运行在Ring3下, 一般情况下,系统进程(也就是System
进程)的页目录(PDE)所在物理地址地址为0x30000,或者说,系统中最小的页目录所在的 物理地址为0x30000.而页目录(PDE)由
1024项组成,每项均指向一页表(PTE),每一页表也由1024个页组成,而每页的大小为 4K,1024*4=4096(0x1000),所以,上面从物
理地址0x30000开始映射了0x1000个字节.(具体描述见WebCrazy的文章<<小议Windows NT/2000的分页机制>>)

程序打开打开内核对象\Device\PhysicalMemory后,继续用函数ZwOpenFile打开内 核对象\Device\Tcp和Device\Udp,ZwOpenFile
函数的原型如下:
NTSYSAPI
NTSTATUS
NTAPI
ZwOpenFile(
OUT PHANDLE FileHandle,
IN ACCESS_MASK DesiredAccess,
IN POBJECT_ATTRIBUTES ObjectAttributes,
OUT PIO_STATUS_BLOCK IoStatusBlock,
IN ULONG ShareAccess,
IN ULONG OpenOptions
);
(见ntddk.h)

第一个参数返回打开对象的句柄
第二个参数DesiredAccess为一个常数,可以是下列值:
#define FILE_READ_DATA ( 0x0001 ) // file & pipe
#define FILE_LIST_DIRECTORY ( 0x0001 ) // directory
#define FILE_WRITE_DATA ( 0x0002 ) // file & pipe
#define FILE_ADD_FILE ( 0x0002 ) // directory
#define FILE_APPEND_DATA ( 0x0004 ) // file
#define FILE_ADD_SUBDIRECTORY ( 0x0004 ) // directory
#define FILE_CREATE_PIPE_INSTANCE ( 0x0004 ) // named pipe
#define FILE_READ_EA ( 0x0008 ) // file & directory
#define FILE_WRITE_EA ( 0x0010 ) // file & directory
#define FILE_EXECUTE ( 0x0020 ) // file
#define FILE_TRAVERSE ( 0x0020 ) // directory
#define FILE_DELETE_CHILD ( 0x0040 ) // directory
#define FILE_READ_ATTRIBUTES ( 0x0080 ) // all
#define FILE_WRITE_ATTRIBUTES ( 0x0100 ) // all
#define FILE_ALL_ACCESS (STANDARD_RIGHTS_REQUIRED | SYNCHRONIZE | 0x1FF)
#define FILE_GENERIC_READ (STANDARD_RIGHTS_READ |\
FILE_READ_DATA |\
FILE_READ_ATTRIBUTES |\
FILE_READ_EA |\
SYNCHRONIZE)
#define FILE_GENERIC_WRITE (STANDARD_RIGHTS_WRITE |\
FILE_WRITE_DATA |\
FILE_WRITE_ATTRIBUTES |\
FILE_WRITE_EA |\
FILE_APPEND_DATA |\
SYNCHRONIZE)
#define FILE_GENERIC_EXECUTE (STANDARD_RIGHTS_EXECUTE |\
FILE_READ_ATTRIBUTES |\
FILE_EXECUTE |\
SYNCHRONIZE)
(见ntdef.h)
第三个参数是一个结构,包含要打开的对象类型等信息,结构定义见上面所述
第四个参数返回打开对象的属性,是一个结构,定义如下:
typedef struct _IO_STATUS_BLOCK {
union {
NTSTATUS Status;
PVOID Pointer;
};

ULONG_PTR Information;
} IO_STATUS_BLOCK, *PIO_STATUS_BLOCK;

#if defined(_WIN64)
typedef struct _IO_STATUS_BLOCK32 {
NTSTATUS Status;
ULONG Information;
} IO_STATUS_BLOCK32, *PIO_STATUS_BLOCK32;
#endif
(见ntddk.h)
第五个参数ShareAccess是一个常数,可以是下列值:
#define FILE_SHARE_READ 0x00000001 // winnt
#define FILE_SHARE_WRITE 0x00000002 // winnt
#define FILE_SHARE_DELETE 0x00000004 // winnt
(见ntddk.h)
第六个参数OpenOptions也是一个常数,可以是下列的值:
#define FILE_DIRECTORY_FILE 0x00000001
#define FILE_WRITE_THROUGH 0x00000002
#define FILE_SEQUENTIAL_ONLY 0x00000004
#define FILE_NO_INTERMEDIATE_BUFFERING 0x00000008
#define FILE_SYNCHRONOUS_IO_ALERT 0x00000010
#define FILE_SYNCHRONOUS_IO_NONALERT 0x00000020
#define FILE_NON_DIRECTORY_FILE 0x00000040
#define FILE_CREATE_TREE_CONNECTION 0x00000080
#define FILE_COMPLETE_IF_OPLOCKED 0x00000100
#define FILE_NO_EA_KNOWLEDGE 0x00000200
#define FILE_OPEN_FOR_RECOVERY 0x00000400
#define FILE_RANDOM_ACCESS 0x00000800
#define FILE_DELETE_ON_CLOSE 0x00001000
#define FILE_OPEN_BY_FILE_ID 0x00002000
#define FILE_OPEN_FOR_BACKUP_INTENT 0x00004000
#define FILE_NO_COMPRESSION 0x00008000
#define FILE_RESERVE_OPFILTER 0x00100000
#define FILE_OPEN_REPARSE_POINT 0x00200000
#define FILE_OPEN_NO_RECALL 0x00400000
#define FILE_OPEN_FOR_FREE_SPACE_QUERY 0x00800000
#define FILE_COPY_STRUCTURED_STORAGE 0x00000041
#define FILE_STRUCTURED_STORAGE 0x00000441
#define FILE_VALID_OPTION_FLAGS 0x00ffffff
#define FILE_VALID_PIPE_OPTION_FLAGS 0x00000032
#define FILE_VALID_MAILSLOT_OPTION_FLAGS 0x00000032
#define FILE_VALID_SET_FLAGS 0x00000036
(见ntddk.h)

那么,打开内核对象\Device\Tcp和\Device\Udp的语句如下:
WCHAR physmemNameTcp[]=L"\\Device\\TCP";
WCHAR physmemNameUdp[]=L"\\Device\\UDP";
HANDLE pTcpHandle;
HANDLE pUdpHandle;

HANDLE OpenDeviceTcpUdp(WCHAR * deviceName)
{
NTSTATUS status;
UNICODE_STRING physmemString;
OBJECT_ATTRIBUTES attributes;
IO_STATUS_BLOCK iosb;
HANDLE pDeviceHandle;

RtlInitUnicodeString(&physmemString, deviceName);
if(GetLastError()!=0)
return NULL;
InitializeObjectAttributes( &attributes,&physmemString,
OBJ_CASE_INSENSITIVE,0, NULL );
status = ZwOpenFile ( &pDeviceHandle,0x100000, &attributes, &iosb, 3,0);
if( !NT_SUCCESS( status ))
return NULL;
}

接着,程序用ZwQuerySystemInformation函数获得系统当前所以进程的所建立的句 柄及其相关信息,函数的原型如下:
NTSYSAPI
NTSTATUS
NTAPI
ZwQuerySystemInformation(
IN SYSTEM_INFORMATION_CLASS SystemInformationClass,
IN OUT PVOID SystemInformation,
IN ULONG SystemInformationLength,
OUT PULONG ReturnLength OPTIONAL
};
(这个函数结构Microsoft没有公开,参见Gary Nebbett<>)

第一个参数是一个枚举常数,设置要查询的系统信息类型,ZwQuerySystemInformation 支持54个系统信息的查询,我们要用到的
是它的第16号功能,进行SystemHandleInformation查询.
SYSTEM_HANDLE_INFORMATION结构定义如下:
typedef struct _SYSTEM_HANDLE_INFORMATION{
ULONG ProcessID; //进程的标识ID
UCHAR ObjectTypeNumber; //对象类型
UCHAR Flags; //0x01 = PROTECT_FROM_CLOSE,0x02 = INHERIT
USHORT Handle; //对象句柄的数值
PVOID Object; //对象句柄所指的内核对象地 址
ACCESS_MASK GrantedAccess; //创建句柄时所准许的对象的 访问权
}SYSTEM_HANDLE_INFORMATION, * PSYSTEM_HANDLE_INFORMATION;
(这个函数结构Microsoft没有公开,参见Gary Nebbett<>)
第二个参数输出查询的结果
第三个参数设置缓冲区的长度
第四个参数返回函数正确执行需要的缓冲区的大小
代码如下:
#define SystemHandleInformation 16
PULONG GetHandleList()
{
ULONG cbBuffer = 0x1000; //先设定一个较小的缓冲空间
PULONG pBuffer = new ULONG[cbBuffer]; //分配内存
NTSTATUS Status;

do
{
Status = ZwQuerySystemInformation(
SystemHandleInformation,
pBuffer, cbBuffer * sizeof * pBuffer, NULL);

if (Status == STATUS_INFO_LENGTH_MISMATCH)
{
//如果返回的错误信息为缓冲区长度不够,那么重新分配内 存
delete [] pBuffer;
pBuffer = new ULONG[cbBuffer *= 2];
}
else if (!NT_SUCCESS(Status))
{
//如果是其他错误信息,返回
delete [] pBuffer;
return false;
}
}
while (Status == STATUS_INFO_LENGTH_MISMATCH);
return pBuffer;
}

因为如果一个进程打开了端口,那么它肯定会建立类型为\Device\Tcp和\Device\Udp的 内核对象,所以,我们在当前进程中打开
上述的两个内核对象,在打开的同时保存了打开的句柄,这样,我们可以在上面获得的句 柄列表中的当前进程中查找对象句柄的
数值和我们保存的两个打开的内核对象的句柄数值相同的句柄,并得到其句柄所指向的 内核对象的地址.代码如下:
DWORD TcpHandle;
DWORD UdpHandle;
DWORD GetTcpUdpObject(PULONG pBuffer,HANDLE pHandle,DWORD ProcessId)
{
DWORD objTYPE1,objTYPE2,HandleObject;

PSYSTEM_HANDLE_INFORMATION pProcesses = (PSYSTEM_HANDLE_INFORMATION)(pBuffer+1);

for (i=0;i< * pBuffer;i++)
{
if ((pProcesses[i].ProcessID) == ProcessId)
{
objTYPE1 = (DWORD)hDeviceTcpUdp;
objTYPE2 = (DWORD)pProcesses[i].Handle;
if(objTYPE1==objTYPE2)
{
HandleObject = (DWORD)pProcesses.Object;
return HandleObject;
}
}
return 0;
}

这个内核对象地址是一个线性地址,我们需要把这个地址转换为物理地址,并得到一些 相关的数据.在fport中,换算是这样进行的:
(具体描述见WebCrazy的文章<<小议Windows NT/2000的分页机制>>)
void * NewmapPhy;

void GetPTE(DWORD objAddress)
{
DWORD physmemBuff;
DWORD newAddress1,newAddress2,newAddress3,newAddress4;
DWORD * newAddress;

physmemBuff = (DWORD)pMapPhysicalMemory;
newAddress1 = physmemBuff+(objAddress>>0x16)*4;
newAddress = (DWORD *)newAddress1;
newAddress1 = * newAddress;
newAddress2 = objAddress & 0x3FF000;
newAddress3 = newAddress1 & 0x0FFFFF000;
newAddress4 = newAddress2 + newAddress3;
NewmapPhy = MapViewOfFile(ghPhysicalMemory,FILE_MAP_READ,0,newAddress4,0x1000);
//重新映射物理内存,得到当前线性地址所指向的PTE的物理地址内容
}

然后在根据内核对象的线性地址得到这个地址所指向的物理页,得到体现当前内核对象 内容的页,其结构如下:
typedef struct {
ULONG Present;
ULONG WriteTable;
ULONG User;
ULONG WriteThru;
ULONG NoCache;
ULONG Accessed;
ULONG Dirty;
ULONG PageSize;
ULONG Global;
ULONG Available;
ULONG Pfn;
} PTE, *PPTE;
(注:我不能保证这个结构的正确性,但我们只会用到其中的两个值,对程序来说,这个结 构是可以工作的,^_^)
代码如下:
ULONG CurrWriteTable;
ULONG NoCache;

void GetMustPar(DWORD objAddress)
{
DWORD CurrAddress;
CurrAddress = objAddress & 0xFFF;
PPTE pte = (PPTE)(VOID *)((DWORD)NewmapPhy+CurrAddress);
CurrWriteTable = pte->WriteTable;
CurrNoCache = Pte->NoCache;
}

好了,我们现在想要得到的都已经得到了,下面需要做的是遍历进程,用每一个进程中的 每一个句柄(呵呵,不是每一个句柄,
在Windows NT下,\Device\Tcp和\Device\Udp的句柄类型值为0x16,在Windows 2000下 这个值为0x1A)的核心地址用上面所描
述的办法得到其PTE内容,得到其WriteTable值,如果与内核对象\Device\Tcp和 \Device\Udp相等,那么这个句柄就有可能打开
了一个端口,再对这个句柄进行确认,就可以了.确认的代码如下:
typedef struct _TDI_CONNECTION_INFO {
ULONG State;
ULONG Event;
ULONG TransmittedTsdus;
ULONG ReceivedTsdus;
ULONG TransmissionErrors;
ULONG ReceiveErrors;
LARGE_INTEGER Throughput;
LARGE_INTEGER Delay;
ULONG SendBufferSize;
ULONG ReceiveBufferSize;
BOOLEAN Unreliable;
} TDI_CONNECTION_INFO, *PTDI_CONNECTION_INFO;

typedef struct _TDI_CONNECTION_INFORMATION {
LONG UserDataLength;
PVOID UserData;
LONG OptionsLength;
PVOID Options;
LONG RemoteAddressLength;
PVOID RemoteAddress;
} TDI_CONNECTION_INFORMATION, *PTDI_CONNECTION_INFORMATION;
(以上结构见tdi.h)

void GetOpenPort(DWORD dwProcessesID,USHORT Handle,int NoCache)
//dwProcessesID为进程标识ID
//Handle为进程打开的句柄,并且经过比较为\Device\Tcp或\Device\Udp类型
//NoCache为PTE结构中的一个值
{
HANDLE hProc,DupHandle=NULL;
HANDLE hEven=NULL;
OVERLAPPED overlap;
u_short openport;
int i=0;
char procName[256]={0};
int portflag=0;

overlap.Internal = 0;
overlap.InternalHigh = 0;
overlap.Offset = 0;
overlap.OffsetHigh = 0;
hEven=CreateEvent(0,1,0,0);
overlap.hEvent = hEven;

hProc = OpenProcess(PROCESS_DUP_HANDLE,
0,
dwProcessesID);
if(hProc)
{
DuplicateHandle(hProc,
(HANDLE)Handle,
GetCurrentProcess(),
&DupHandle,
0,
FALSE,
2);
CloseHandle( hProc );
if(DupHandle)
{
TDI_CONNECTION_INFO TdiConnInfo={0};
TDI_CONNECTION_INFORMATION TdiConnInformation={0};
DWORD dwRetu=0;

if(NoCache==0x2)
{
TdiConnInformation.RemoteAddressLength= 4;
if(DeviceIoControl(DupHandle,0x210012,
&TdiConnInformation,sizeof(TdiConnInformation),
&TdiConnInfo,sizeof(TdiConnInfo),
0,&overlap))
//进行TDI查询,得到连接的相关信息
{
openport = ntohs((u_short)TdiConnInfo.ReceivedTsdus);
procname = GetProcName(dwProcessesID); //得到进程标识ID的进程名称
printf("PID = %4d ProcessName = %15s PORT = %4d\n",dwProcessesID,procName,openport);
}
}
if(NoCache==0x1)
{
TdiConnInformation.RemoteAddressLength= 3;
if(DeviceIoControl(DupHandle,0x210012,
&TdiConnInformation,sizeof(TdiConnInformation),
&TdiConnInfo,sizeof(TdiConnInfo),
0,&overlap))
//进行TDI查询,得到连接的相关信息
{
openport = ntohs((u_short)TdiConnInfo.ReceivedTsdus);
procname = GetProcName(dwProcessesID); //得到进程标识ID的进程名称
printf("PID = %4d ProcessName = %15s PORT = %4d\n",dwProcessesID,procName,openport);
}
}
}
}
CloseHandle(hEven);
CloseHandle(DupHandle);
}

以上是我对fport.exe的分析及其实现代码,演示程序可以从whitecell.org下载,如果 你发现有问题,请通知我,^_^

参考:

fport.exe
Gary Nebbett<>
WebCrazy<<小议Windows NT/2000分页机制>>
NTDDK


关于我们 | 加入我们 | 网站结构 | 交换连接 | 联系我们

20CN网络安全小组版权所有
Copyright © 2000-2010 20CN Network Security Group.
All Rights Reserved.
W3C XHTML 1.0 Strict & CSS 1.2 Valid.