C / C++ / MFC

Re: Windows XP Convert SystemDrive Variable e.g. %SystemDrive% - into equivelant C++ code

2-Sep-20 22:48

Here is one encouraging bit of news though I have stumbled upon the very thing I need called WFPReplacer, it is a commandline windows utility that pretty well does what I want & generally in the same manner. it disables WFP for both singular files & can be used for wholesale switching off of WFP if the right file is replaced. All I need to do is write a batch file as a front end to back up the system files I want to disable use WFPReplacer.exe. So if in the event of the proceedings the routine gets stuffed I can revert back to the backed up files. I think this program uses the same type of embedded coding but is written in Delphi/pascal, it is called Remko Weijnen's Blog (Remko's Blog) "replacing Wfp protected files".

I generally like to leave whatever I am doing on a positive note. And NO I do not have any interest in coding Malware, so just in case someone else lands on this forum & is trying to accomplish a similair exercise here is the code that one can compile (This is not my code it belongs to Remko Weijnen's Blog (Remko's Blog)) Please be advised it is NOT C++ it is a commandline exe Delhi/Pascal found at this link, so all credits belong to him. The link is:

https://www.remkoweijnen.nl/blog/2012/12/05/replacing-wfp-protected-files/

Delphi

DWORD __stdcall SfcFileException(RPC_BINDING_HANDLE hServer, LPCWSTR lpSrc, int Unknown)
{
  RPC_BINDING_HANDLE hServerVar; // eax@2
  int nts; // eax@6
  __int32 dwResult; // eax@7
  DWORD dwResultVar; // esi@9
  int v8; // [sp+8h] [bp-8h]@1
  int v9; // [sp+Ch] [bp-4h]@1

  LOWORD(v8) = 0;
  *(int *)((char *)&v8 + 2) = 0;
  HIWORD(v9) = 0;
  if ( !hServer )
  {
    hServerVar = _pRpcHandle;
    if ( !_pRpcHandle )
    {
      hServerVar = SfcConnectToServer(0);
      _pRpcHandle = hServerVar;
      if ( !hServerVar )
        return 0x6BA;                           // RPC_S_SERVER_UNAVAILABLE
    }
    hServer = hServerVar;
  }
  nts = SfcRedirectPath(lpSrc, (int)&v8);
  if ( nts >= 0 )
    dwResult = SfcCli_FileException((int)hServer, v9, Unknown).Simple;
  else
    dwResult = RtlNtStatusToDosError(nts);
  dwResultVar = dwResult;
  MemFree(v9);
  return dwResultVar;
}

Also as one further warning (Unless you know what you are doing!!!) do not attempt to use this program, ALWAYS ALWAYS ALWAYS backup your system files before deletion or alteration.
What this program will do is disarm WFP for 60 seconds whilst you intercange or amend your files. Example usage for example is:
WfpReplacer.exe c:\windows\Notepad.exe (Errorlevel true or false will be produced on execution).

Best Regards
David

David Crow3-Sep-20 2:59

Re: Windows XP Convert SystemDrive Variable e.g. %SystemDrive% - into equivelant C++ code

3-Sep-20 2:59

jackngill wrote:

My question is there a equivelent C++ code for the SystemDrive variable...

Check out SHGetKnownFolderPath() or SHGetFolderPath().

"One man's wage rise is another man's price increase." - Harold Wilson

"Fireproof doesn't mean the fire will never come. It means when the fire comes that you will be able to withstand it." - Michael Simmons

"You can easily judge the character of a man by how he treats those who can do nothing for him." - James D. Miles

jackngill3-Sep-20 4:01

Re: Windows XP Convert SystemDrive Variable e.g. %SystemDrive% - into equivelant C++ code

3-Sep-20 4:01

Hi David,

Thanks for your post but your answer I think is for vista & above could be wrong but my ? is related to XP
Found this though:
Most of the constants are based on documented CSIDL's ( http://msdn.microsoft.com/en-us/library/bb762494%28v=VS.85%29.aspx ) except temp and quicklaunch IIRC. There is no documented api to get the systemdrive AFAIK so ReadEnvStr is as native as this is going to get.

ReadEnvStr $0 "SYSTEMDRIVE"

status: open --> closed

But even that is not even injectable into the line SetSfcFileException(0, L"c:\\windows\\system32\\calc.exe",-1); as the above only states open or closed status. I think ultimately I am flogging a dead horse, was hoping for a quick easy interchange of code but looks like the answer will require multi-lines of code & I am incapable of undertaking that.

But regardless many thanks for the response david

David Crow3-Sep-20 4:23

Re: Windows XP Convert SystemDrive Variable e.g. %SystemDrive% - into equivelant C++ code

3-Sep-20 4:23

jackngill wrote:
There is no documented api to get the systemdrive AFAIK

Maybe, maybe not. But taking the first letter of CSIDL_SYSTEM or CSIDL_WINDOWS, for example, will get you the correct drive.

Victor Nijegorodov3-Sep-20 6:41

Re: Windows XP Convert SystemDrive Variable e.g. %SystemDrive% - into equivelant C++ code

3-Sep-20 6:41

Or using the PathGetDriveNumberW function (shlwapi.h) - Win32 apps | Microsoft Docs and then "convert" the number to the corresponding letter

David Crow3-Sep-20 7:08

Re: Windows XP Convert SystemDrive Variable e.g. %SystemDrive% - into equivelant C++ code

3-Sep-20 7:08

How exactly would that function return the desired information?

Victor Nijegorodov3-Sep-20 7:47

Re: Windows XP Convert SystemDrive Variable e.g. %SystemDrive% - into equivelant C++ code

3-Sep-20 7:47

AS you suggested:
call any of the SHGetFolderPath(), ... with CSIDL_WINDOWS
and then pass the returned path (say, windowsDir) into PathGetDriveNumber:

WCHAR letter = L'A' + PathGetDriveNumberW(windowsDir);

David Crow3-Sep-20 7:57

Re: Windows XP Convert SystemDrive Variable e.g. %SystemDrive% - into equivelant C++ code

3-Sep-20 7:57

But the return value from SHGetKnownFolderPath() already contains the system's drive letter. There's no need to pass that path to PathGetDriveNumber(), have it return a number, and then convert that number back into a drive letter that was already obtained.

Victor Nijegorodov3-Sep-20 8:04

Re: Windows XP Convert SystemDrive Variable e.g. %SystemDrive% - into equivelant C++ code

3-Sep-20 8:04

Yes, i know it. It was just a proposal to use an API rather than to search for a letter in the returned path ... Smile | :)

David Crow3-Sep-20 8:09

Re: Windows XP Convert SystemDrive Variable e.g. %SystemDrive% - into equivelant C++ code

3-Sep-20 8:09

Victor Nijegorodov wrote:
...rather than to search for a letter in the returned path

Search for something that's always in position 0?

Victor Nijegorodov3-Sep-20 9:27

Re: Windows XP Convert SystemDrive Variable e.g. %SystemDrive% - into equivelant C++ code

3-Sep-20 9:27

Victor Nijegorodov3-Sep-20 8:07

Re: Windows XP Convert SystemDrive Variable e.g. %SystemDrive% - into equivelant C++ code

3-Sep-20 8:07

Once more, my reply was not for you, it was just for the OP... Wink | ;)

Sorry, if I put it in a wrong place! Hmmm | :|

Victor Nijegorodov3-Sep-20 7:47

Re: Windows XP Convert SystemDrive Variable e.g. %SystemDrive% - into equivelant C++ code

3-Sep-20 7:47

AS you suggested:
call any of the SHGetFolderPath(), ... with CSIDL_WINDOWS
and then pass the returned path (say, windowsDir) into PathGetDriveNumber:

WCHAR letter = L'A' + PathGetDriveNumberW(windowsDir);

jackngill3-Sep-20 11:41

Re: Windows XP Convert SystemDrive Variable e.g. %SystemDrive% - into equivelant C++ code

3-Sep-20 11:41

Hi folks thanks for the input,

PathGetDriveNumberA function
Searches a path for a drive letter within the range of 'A' to 'Z' and returns the corresponding drive number.
Syntax

int PathGetDriveNumberA(
  LPCSTR pszPath
);

Parameters
pszPath
Type: LPCTSTR
A pointer to a null-terminated string of maximum length MAX_PATH that contains the path to be searched.
Return value
Type: int
Returns 0 through 25 (corresponding to 'A' through 'Z') if the path has a drive letter, or -1 otherwise.

Remarks
Note

The shlwapi.h header defines PathGetDriveNumber as an alias which automatically selects the ANSI or Unicode version of this function based on the definition of the UNICODE preprocessor constant. Mixing usage of the encoding-neutral alias with code that not encoding-neutral can lead to mismatches that result in compilation or runtime errors. For more information, see Conventions for Function Prototypes.

Taken from: PathGetDriveNumberA function (shlwapi.h) - Win32 apps | Microsoft Docs[^]

does this help in any way?

Regards

Jackngill

Victor Nijegorodov3-Sep-20 22:29

Re: Windows XP Convert SystemDrive Variable e.g. %SystemDrive% - into equivelant C++ code

3-Sep-20 22:29

jackngill wrote:
does this help in any way?

Yes.
However, I'd use another way (more simple). See my post here: Re: Windows XP Convert SystemDrive Variable e.g. %SystemDrive% - into equivelant C++ code - C / C++ / MFC Discussion Boards

Victor Nijegorodov3-Sep-20 4:08

Re: Windows XP Convert SystemDrive Variable e.g. %SystemDrive% - into equivelant C++ code

3-Sep-20 4:08

Did you try GetEnvironmentVariable function (winbase.h) - Win32 apps | Microsoft Docs ?

jackngill4-Sep-20 2:11

Re: Windows XP Convert SystemDrive Variable e.g. %SystemDrive% - into equivelant C++ code

4-Sep-20 2:11

Hi Victor
Many thanks can I take a further liberty in answering your question with yet another question?
Your "?" - Did you try GetEnvironmentVariable function (winbase.h) - Win32 apps | Microsoft Docs ?
Can I answer with:
Is there (of some Kind like for instance Emu8086) that would be able to run C++ code to check if it works & possibly feedback errors compatable that is compatable with XP as my skills in C++ are shall we say are very sadly lacking as suggested in my 1st post. I know what I want to do but don't know how to get there. The short answer is no sorry!

I have been researching further & I have found this snippet of code from (To reveal the source click on the link below)
C++/CLI Code Snippet - Access current environment directories and logical drives[^]

which states this

C++

// Gets the home drive - %HOMEDRIVE% (possible HOMEDRIVE is related to Windows7)
// Typical value - C:
Console::WriteLine("Get Environment Variable: Home Drive " + Environment::GetEnvironmentVariable("HOMEDRIVE"));

However Line 15 (the last 2 lines) is all one line & it states Writeline which infers output to console?
Then could Homedrive be called/injected into this line in the first post

C++

SetSfcFileException(0, L"c:\\windows\\system32\\calc.exe",-1);

like this:

C++

SetSfcFileException(0, L"HOMEDRIVE:\\windows\\system32\\calc.exe",-1);

I am assuming I would need new headers & would need to know where to insert the code. I am assuming prior to the execution of the code in the 1st post I made (which I did not write), because once the code is executed within the C++ it would remain memory resident to access later to envoke the HOMEDRIVE system variable. Hope I am not blowing smoke here just a theory?

P.S. Is the C++ code in post 1 for windows or commandline as the above code I think is for commandline, I wouldn't have thought mixing code from two standpoints would Not be Good?

All the best,

Jackngill

modified 4-Sep-20 9:35am.

Victor Nijegorodov4-Sep-20 7:59

Re: Windows XP Convert SystemDrive Variable e.g. %SystemDrive% - into equivelant C++ code

4-Sep-20 7:59

jackngill wrote:
I have been researching further & I have found this snippet of code from (To reveal the source click on the link below)
C++/CLI Code Snippet - Access current environment directories and logical drives[^]

The sample from CPP-CLI source has nothing to do with the native C++ code that you seem to be using!
Try this:

C++

TCHAR buffer[30] = {0};
    if (::GetEnvironmentVariable(_T("SYSTEMDRIVE"), buffer, _countof(buffer)))
    {
        TCHAR path[MAX_PATH] = {0};
        _stprintf(path, _T("%s\windows\system32\calc.exe"), buffer);
        TRACE(path); // just to be sure it is what we supposed...
        SetSfcFileException(0, path, -1);
    }

jackngill4-Sep-20 10:06

Re: Windows XP Convert SystemDrive Variable e.g. %SystemDrive% - into equivelant C++ code

4-Sep-20 10:06

Hi Victor,

Sorry about the prior code snippet apologies.

I have copied your code and ran it here:

https://www.onlinegdb.com/online_c++_compiler[^]

Unfortunately it came up with a few errors:
Compilation failed due to following error(s). main.cpp:1:1: error: ‘TCHAR’ does not name a type
TCHAR buffer[30] = {0};
^~~~~
main.cpp:2:5: error: expected unqualified-id before ‘if’
if (::GetEnvironmentVariable(_T("SYSTEMDRIVE"), buffer, _countof(buffer)))
^~

Do these error codes mean anything to you?

Best Regards

David

Victor Nijegorodov4-Sep-20 21:37

Re: Windows XP Convert SystemDrive Variable e.g. %SystemDrive% - into equivelant C++ code

4-Sep-20 21:37

I have no idea what compiler you are using...
If you compile it as UNICODE then replace TCHAR with wchar_t, _T() macro - with L, and _stprintf - with swprintf.

Besides, learn using Google to fast search for such types of errors...

jackngill4-Sep-20 23:05

Re: Windows XP Convert SystemDrive Variable e.g. %SystemDrive% - into equivelant C++ code

4-Sep-20 23:05

Hi Victor,

I am using online compiler as I am not setup to compile programs see link here:

https://www.onlinegdb.com/online_c++_compiler[^]

The file is temp called main.cpp enter the code and depress run small dialogue box at the bottom of the screen generates errors with indicators like with exchanged code as you suggested:

Compilation failed due to following error(s). main.cpp:1:8: error: expected unqualified-id before ‘,’ token
 wchar_t, _T() buffer[30] = {0};
        ^
main.cpp:1:15: error: expected initializer before ‘buffer’
 wchar_t, _T() buffer[30] = {0};
               ^~~~~~
main.cpp:2:5: error: expected unqualified-id before ‘if’
     if (::GetEnvironmentVariable(_T("SYSTEMDRIVE"), buffer, _countof(buffer)))
     ^~

For this:

wchar_t, _T() buffer[30] = {0};
    if (::GetEnvironmentVariable(_T("SYSTEMDRIVE"), buffer, _countof(buffer)))
    {
        wchar_t, _T() path[MAX_PATH] = {0};
        swprintf(path, _T("%s\windows\system32\calc.exe"), buffer);
        TRACE(path); // just to be sure it is what we supposed...
        SetSfcFileException(0, path, -1);
    }

Could not find macro - with L in your code.

I will research further error codes on WWW & get back to you

Best Regards

David

Victor Nijegorodov4-Sep-20 23:19

Re: Windows XP Convert SystemDrive Variable e.g. %SystemDrive% - into equivelant C++ code

4-Sep-20 23:19

jackngill wrote:

Compilation failed due to following error(s). main.cpp:1:8: error: expected unqualified-id before ‘,’ token
 wchar_t, _T() buffer[30] = {0};
        ^
main.cpp:1:15: error: expected initializer before ‘buffer’
 wchar_t, _T() buffer[30] = {0};
               ^~~~~~
main.cpp:2:5: error: expected unqualified-id before ‘if’
     if (::GetEnvironmentVariable(_T("SYSTEMDRIVE"), buffer, _countof(buffer)))
     ^~

For this:

wchar_t, _T() buffer[30] = {0};
    if (::GetEnvironmentVariable(_T("SYSTEMDRIVE"), buffer, _countof(buffer)))
    {
        wchar_t, _T() path[MAX_PATH] = {0};
        swprintf(path, _T("%s\windows\system32\calc.exe"), buffer);
        TRACE(path); // just to be sure it is what we supposed...
        SetSfcFileException(0, path, -1);
    }

What the abracadabra you wrote? Thumbs Down | :thumbsdown:

Try

C++

wchar_t buffer[30] = {0};
if (::GetEnvironmentVariable(L"SYSTEMDRIVE", buffer, 30))
{
   wchar_t path[MAX_PATH] = {0};
   swprintf(path, L"%s\windows\system32\calc.exe", buffer);
   TRACE(path); // just to be sure it is what we supposed...
   SetSfcFileException(0, path, -1);
}

jackngill4-Sep-20 23:54

Re: Windows XP Convert SystemDrive Variable e.g. %SystemDrive% - into equivelant C++ code

4-Sep-20 23:54

The only error now being reported back is this one by the way sorry for the gobble-de-gook code must have cut & paste wrong.

main.cpp:2:1: error: expected unqualified-id before ‘if’
if (::GetEnvironmentVariable(L"SYSTEMDRIVE", buffer, 30))
^~

"If" for some reason is proving a problem but only one error repoted though encouraging it is under the input tab on the compiler. Perhaps an if/else might work?
Best Regards,

David

modified 5-Sep-20 6:07am.

Victor Nijegorodov5-Sep-20 0:07