首先利用PsGetCurrentProcess或IoGetCurrentProcess函数得到当前进程的句柄，这个句柄是指向_EPROCESS结构的指针，_EPROCESS的结构如下：
typedef struct _EPROCESS
{
KPROCESS Pcb;
NTSTATUS ExitStatus;
KEVENT LockEvent;
DWORD LockCount;
QWORD CreateTime;
QWORD ExitTime;
PVOID LockOwner;
DWORD UniqueProcessId;
QWORD ActiveProcessLinks;
DWORD QuotaPeakPoolUsage [2]; // NP, P
DWORD QuotaPoolUsage [2]; // NP, P
DWORD PagefileUsage;
DWORD CommitCharge;
DWORD PeakPagefileUsage;
DWORD PeakVirtualSize;
QWORD VirtualSize;
DWORD Vm [12];
DWORD LastProtoPteFault;
DWORD DebugPort;
DWORD ExceptionPort;
DWORD ObjectTable;
DWORD Token;
DWORD WorkingSetLock [8];
DWORD WorkingSetPage;
BOOLEAN ProcessOutswapEnabled;
BOOLEAN ProcessOutswapped;
BOOLEAN AddressSpaceInitialized;
BOOLEAN AddressSpaceDeleted;
DWORD AddressCreationLock [9];
DWORD ForkInProgress;
DWORD VmOperation;
DWORD VmOperationEvent;
DWORD PageDirectoryPte;
QWORD LastFaultCount;
PVOID VadRoot;
DWORD VadHint;
DWORD CloneRoot;
DWORD NumberOfPrivatePages;
DWORD NumberOfLockedPages;
WORD w184;
BOOLEAN ExitProcessCalled;
BOOLEAN CreateProcessReported;
HANDLE SectionHandle;
struct _PEB *Peb; // offset 0x1B0
PVOID SectionBaseAddress;
PVOID QuotaBlock;
NTSTATUS LastThreadExitStatus;
PROCESS_WS_WATCH_INFORMATION WorkingSetWatch;
DWORD InheritedFromUniqueProcessId;
ACCESS_MASK GrantedAccess;
DWORD DefaultHardErrorProcessing;
DWORD LdtInformation;
DWORD VadFreeHint;
DWORD VdmObjects;
KMUTANT ProcessMutant;
BYTE ImageFileName [16]; // offset 0x1FC
DWORD VmTrimFaultValue [2];
PVOID Win32Process;
DWORD d1F8;
DWORD d1FC;
}
EPROCESS,
* PEPROCESS,
**PPEPROCESS;
从上面这个结构可以看出，进程名称就是ImageFileName，只要用_EPROCESS的基地址加上偏移地址0x1FC就可以得到进程名称的地址，代码如下：
char *ProcessName = (char*)PsGetCurrentProcess() + 0x1FC;
KdPrint((“Current Process Name: %s\n”, ProcessName));
要得到完整路径还需要利用_EPROCESS结构中的_PEB结构指针来得到ProcessParameters的地址。ProcessParameters保存着进程的完整路径。可以通过DDK附带的WinDbg工具打开一个可执行程序，然后用!peb命令来显示_PEB的结构信息。如下所示：
———————————————————————————————————————
> !peb
Debugger extension library [F:\WINNT\system32\ntsdexts] loaded
PEB at 7FFDF000
InheritedAddressSpace: No
ReadImageFileExecOptions: No
BeingDebugged: Yes
ImageBaseAddress: 00400000
Ldr.Initialized: Yes
Ldr.InInitializationOrderModuleList: 131f88 . 132998
Ldr.InLoadOrderModuleList: 131ee0 . 132988
Ldr.InMemoryOrderModuleList: 131ee8 . 132990
00400000 D:\NtSysInfo.exe
77F80000 F:\WINNT\System32\ntdll.dll
77E60000 F:\WINNT\system32\KERNEL32.dll
77DF0000 F:\WINNT\system32\USER32.dll
77F40000 F:\WINNT\system32\GDI32.DLL
76AF0000 F:\WINNT\system32\comdlg32.dll
70BD0000 F:\WINNT\system32\SHLWAPI.DLL
77D90000 F:\WINNT\system32\ADVAPI32.dll
77D20000 F:\WINNT\system32\RPCRT4.DLL
71700000 F:\WINNT\system32\COMCTL32.DLL
77560000 F:\WINNT\system32\SHELL32.DLL
78000000 F:\WINNT\system32\MSVCRT.DLL
777C0000 F:\WINNT\System32\WINSPOOL.DRV
SubSystemData: 0
ProcessHeap: 130000
ProcessParameters: 20000
WindowTitle: 'D:\NtSysInfo.exe'
ImageFile: 'D:\NtSysInfo.exe'
CommandLine: '"D:\NtSysInfo.exe" '
DllPath: 'D:\;.;F:\WINNT\System32;F:\WINNT\system;F:\WINNT;F:\WINNT\system32;F:\WINNT;F:\WINNT\System32\Wbem;J:\WINDOWS;J:\WINDOWS\COMMAND;E:\WINDOWS\SYSTEM\WBEM;J:\WINDOWS;J:\WINDOWS\COMMAND;E:\WINDOWS\SYSTEM\WBEM;J:\WINDOWS;J:\WINDOWS\
COMMAND'
从WinDbg输出的PEB结构信息可以看出ProcessParameters的地址为0x20000，ImageFile字段就是进程的完整路径。那么PorcessParamters的地址又保存在_PEB结构的什么地方呢？_PEB结构的基地址为0x7ffdf000，通过WinDbg的“db 0x7ffdf000” 命令显示0x7ffdf000地址的信息可以发现ProcessParameters的地址保存在_PEB结构的0x10偏移量处，内容为0x20000。
继续用“db 0x20000”命令显示ProcessParameters地址的内容，偏移量为0x3C处保存完整路径的地址，0x3C处的内容如果是：0x20670，利用“db 0x20670”即可显示出完整路径。完整路径用UNICODE格式保存。
我们利用程序模拟上面的步骤则可以得到当前进程的完整路径，代码如下：
PCWSTR GetCurrentProcessFileName()
{
DWORD dwAddress = (DWORD)PsGetCurrentProcess();
if(dwAddress == 0 || dwAddress == 0xFFFFFFFF)
return NULL;
dwAddress += 0x1B0;
if((dwAddress = *(DWORD*)dwAddress) == 0) return 0;
dwAddress += 0x10;
if((dwAddress = *(DWORD*)dwAddress) == 0) return 0;
dwAddress += 0x3C;
if((dwAddress = *(DWORD*)dwAddress) == 0) return 0;
KdPrint((“Current Process Full Path Name: %ws\n”, (PCWSTR)dwAddress));
return (PCWSTR)dwAddress;
}
Windows NT与Windows 2000的_EPROCESS结构略有不同，所以偏移地址也不相同，故此上面的程序不能正常运行于Windows NT。要想在Windows NT下获得进程名和完整路径可以用类似的方法得出正确的偏移地址，进而编写出正确的程序。
如果想得到关于如何在Windows 9x的驱动程序（VXD）中得到当前进程的进程名和完整路径或者其他更多知识，可以访问费尔安全实验室的网站：http://www.xfilt.com。 |
