Question

open files

Asked by: Droby10

i'm interested in knowing the steps to obtaining filehandles or file descriptors for every open file on the system.  i can do it in unix, from studying the fstat source...but there's not a true translation from the kvm_* calls to something in win32...anyone have any ideas?

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Asked On
2001-04-22 at 16:04:41ID20108480
Topic

Windows Programming

Participating Experts
4
Points
250
Comments
15

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Answers

 

by: Droby10Posted on 2001-04-22 at 19:03:11ID: 6025630

i think i'm on the right track following EnumProcesses...OpenProcessToken...OpenProcess...and somehow ending up at GetStdHandle....does this sound logical...? if so what are the parts that i'm missing...?

thanks.

 

by: NickRepinPosted on 2001-04-22 at 21:12:46ID: 6025817

>>EnumProcesses...OpenProcessToken...OpenProcess...and
>>does this sound logical...?

No. There is no documented way.

But there is an undocumented one www.sysinternals.com, HandleEx.

 

by: Droby10Posted on 2001-04-22 at 22:16:10ID: 6025906

thanks nick...i'm actually doing research on a similar product that provides it's own equivalent functionality...i've been debugging through the process with a little luck, but it's ending prematurely in windasm...so i'm having to "fill in the blanks"...i'll have a look at this device driver too, to see if i can get something from it as well and let you know how it goes...thanks.

 

by: jkrPosted on 2001-04-23 at 05:06:04ID: 6026400

If you're using NT, I could offer some source code that uses the NT native API to achieve that (works under W2k also.

 

by: Droby10Posted on 2001-04-23 at 09:09:14ID: 6026567

i'd be very appreciative, thanks...

if it's small enough to post, that would be great...if not, please email it to me at droby10@yahoo.com...

 

by: jkrPosted on 2001-04-23 at 10:13:16ID: 6026651

Do you have the DDK installed?

 

by: Droby10Posted on 2001-04-23 at 11:58:51ID: 6026806

yep...

 

by: jkrPosted on 2001-04-23 at 13:24:29ID: 6027042

OK, here we go:

#define UNICODE
#define _UNICODE
#include <ntdll.h>
#include <tchar.h>
#include <stdio.h>

#pragma waring ( disable: 4768)
#include <list>

//...

typedef std::list<OBJECT_NAME_INFORMATION*> obj_list;


void    AppendObjectInformation (   HANDLE  hObject,    obj_list* pList)
{
    NTSTATUS                    ntStatus;
    OBJECT_BASIC_INFORMATION    obi;
    POBJECT_TYPE_INFORMATION    poti;
    POBJECT_NAME_INFORMATION    poni;
    ULONG                       ul;
   
    ZwQueryObject   (   hObject,
                        ObjectBasicInformation,
                        &obi,
                        sizeof  (   obi),
                        &ul
                    );

    ul  =       obi.TypeInformationLength   +   2;

    poti    =   ( POBJECT_TYPE_INFORMATION) new char    [   ul];

    ntStatus    =   ZwQueryObject   (   hObject,
                                        ObjectTypeInformation,
                                        poti,
                                        ul,
                                        &ul
                                    );

    if  (   wcscmp  (   poti->Name.Buffer, L"File"))
        {
            delete  []  poti;

            return;
        }

    ul  =       !obi.NameInformationLength  
            ?   MAX_PATH * sizeof ( WCHAR)
            :   obi.NameInformationLength;

    poni    =   ( POBJECT_NAME_INFORMATION) new char    [   ul];

    ntStatus    =   ZwQueryObject   (   hObject,
                                        ObjectNameInformation,
                                        poni,
                                        ul,
                                        &ul
                                    );

    pList->push_back    (   poni);

    delete  []  poti;
}

void    GetOpenFileList (   DWORD   dwPID,  obj_list*   pList)
{

    NTSTATUS                    ntStatus;

    HANDLE                      hObject;
    HANDLE                      hProcess;

    PSYSTEM_HANDLE_INFORMATION  pshi;

    ULONG                       ul  =   0x1000;
    PULONG                      pul =   new ULONG   [   ul];

    hProcess    =   OpenProcess (   PROCESS_DUP_HANDLE, FALSE,  dwPID);

    while   (   STATUS_INFO_LENGTH_MISMATCH ==  ZwQuerySystemInformation    (   SystemHandleInformation,
                                                                                pul,
                                                                                ul  *   sizeof  (   ULONG),
                                                                                0
                                                                            )
            )   delete  []  pul,    pul =   new ULONG   [   ul  *=  2];

    pshi    =   ( PSYSTEM_HANDLE_INFORMATION)   ( pul   +   1);

    for (   ULONG   i   =   0;  i   <   *pul;   i++)
        {
            if  (   pshi    [   i].ProcessId    !=  dwPID)  continue;

            hObject =   NULL;

            ZwDuplicateObject   (   hProcess,
                                    ( HANDLE)   pshi    [   i].Handle,
                                    NtCurrentProcess    (),
                                    &hObject,
                                    0,
                                    0,
                                    DUPLICATE_SAME_ATTRIBUTES
                                );

            if  (   hObject)
                    AppendObjectInformation (   hObject, pList);

        }

    delete  []  pul;
}

void PrintList  (   obj_list*   _p)
{
    obj_list::iterator  _i;

    for (   _i  =   _p->begin   ();
            _i  !=  _p->end     ();
            _i++
        )
        {
            wprintf (   L"%s\n",    (*_i)->Name.Buffer);
        }
}

int wmain   (   int         wargc,
                wchar_t**   wargv
            )
{
    DWORD       dwPID;
    wchar_t*    pwc;

    obj_list    _list;

    if  (   2   !=  wargc)
            return  (   -1);

    dwPID   =   wcstol  (   *(  wargv   +   1), &pwc,   10);

    GetOpenFileList (   dwPID,  &_list);

    PrintList   (   &_list);

    return  (   0);

}

The executable itself is on the way via email. If it suits your needs, the project will follow ;-)

 

by: Droby10Posted on 2001-04-23 at 18:36:43ID: 6027516

thanks, this got me where i wanted to go...i would still love to to view the project source, though.

thanks again.

 

by: jkrPosted on 2001-04-24 at 05:50:25ID: 6028870

No prob - will follow soon (have to make some adaptions so that it can be compiled without _my_ DDK paths). Expect it to arrive in a few hours. I will post it here also.

 

by: sisadminPosted on 2003-02-15 at 05:24:08ID: 7955463

Please, send me the project to grisha_ainbinder@yahoo.com
Thank you in advance

 

by: jkrPosted on 2003-02-17 at 06:19:02ID: 7966163

What you are seeing is the whole project - the only thing missing is 'ntdll.h':

#include <windows.h>
 
namespace NT
{
extern "C"
 {
#pragma warning ( disable: 4005)
  #include <basetsd.h>
  #include <ntddk.h>
#pragma warning ( default: 4005)
 }
}
 
using NT::NTSTATUS;
using NT::UNICODE_STRING;
using NT::PUNICODE_STRING;
using NT::OBJECT_ATTRIBUTES;

 

by: sisadminPosted on 2003-02-18 at 06:04:27ID: 7974069

Hi.
I was unable to compile it. I run the BLD command from the DDK (2600) cmd line (with TARGET=PROGRAM) and it returns with 44 errors
Like:
e:\winddk\inc\ddk\wxp\ntddk.h(12691) : error C2664: 'InterlockedPushEntrySList' : cannot convert parameter 2 from 'NT::PSINGLE_LIST_ENTRY' to 'PSINGLE_LIST_ENTRY'

or

main.cpp(21) : error C2065: 'ZwQueryObject' : undeclared identifier.

Would you, please, send the project or tell me what am I doing wrong ?
thanks again

 

by: d97ulmPosted on 2003-02-18 at 21:47:41ID: 7979767

Hi,

I would appritiate if you could send me all related files (src+binary) to ulma4761@student.uu.se

I was thinking of writing a "lsof" equivalent for windows

Thanks

 

by: jkrPosted on 2003-02-22 at 20:32:29ID: 8001559

>>:\winddk\inc\ddk\wxp\ntddk.h(12691) :

I never tested that code with the XP SDK, sorry.

20120131-EE-VQP-002

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