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Retrieving File Sector Location Using a Minifilter

chex2020chex2020 Member Posts: 4

Please is there a structure to retrieve the disk sector(s) occupied by a file in kernel mode?

Comments

  • Peter_Viscarola_(OSR)Peter_Viscarola_(OSR) Administrator Posts: 8,090

    Did you even try Googling for this.

    FSCTL_GET_RETRIEVAL_POINTERS is what you want.

    Peter

    Peter Viscarola
    OSR
    @OSRDrivers

  • chex2020chex2020 Member Posts: 4

    Thank you very much. I did try to google it but maybe because I didn't know what I was looking for I couldn't find it. The structure below is the closest I came to finding a solution. I haven't tried to use it yet, so I'm glad I have to have something else to explore.

    extern "C" BOOL ReadDiskSector(int drive, DWORD startinglogicalsector, int numberofsectors, BYTE *buffer)
    {
    HANDLE hDevice;
    DWORD bytesread;

    // Creating a handle to drive a: using CreateFile () function ..   
    char _devicename[] = "\\\\.\\PhysicalDrive0";   
    _devicename[17] += drive;   
    hDevice = CreateFile(_devicename,  // drive to open   
                        GENERIC_READ,     // access type   
                        FILE_SHARE_READ | // share mode   
                        FILE_SHARE_WRITE,    
                        NULL,             // default security attributes   
                        OPEN_EXISTING,    // disposition   
                        0,                // file attributes   
                        NULL);            // do not copy file attributes   
    
    
    if (hDevice == INVALID_HANDLE_VALUE)    
        return FALSE;   
    
    DiskFileSeek(hDevice, (startinglogicalsector),FILE_BEGIN);   
    
    if (!ReadFile (hDevice, buffer, 512*numberofsectors, &bytesread, NULL) )   
         return FALSE;   
    
    CloseHandle(hDevice);    
    return TRUE;   
    

    }

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