drivers/filesystems/fs_rec/ext2.c

   1 /*
   2  * COPYRIGHT:        See COPYING in the top level directory
   3  * PROJECT:          ReactOS File System Recognizer
   4  * FILE:             drivers/filesystems/fs_rec/ext2.c
   5  * PURPOSE:          EXT2 Recognizer
   6  * PROGRAMMER:       Eric Kohl
   7  */
   8
   9 /* INCLUDES *****************************************************************/
  10
  11 #include "fs_rec.h"
  12 #define NDEBUG
  13 #include <debug.h>
  14
  15 /* FUNCTIONS ****************************************************************/
  16
  17 BOOLEAN
  18 NTAPI
  19 FsRecIsExt2Volume(IN PVOID PackedBootSector)
  20 {
  21     UNREFERENCED_PARAMETER(PackedBootSector);
  22     /* For now, always return failure... */
  23     return FALSE;
  24 }
  25
  26 NTSTATUS
  27 NTAPI
  28 FsRecExt2FsControl(IN PDEVICE_OBJECT DeviceObject,
  29                    IN PIRP Irp)
  30 {
  31     PIO_STACK_LOCATION Stack;
  32     NTSTATUS Status;
  33     PDEVICE_OBJECT MountDevice;
  34     PVOID Bpb = NULL;
  35     ULONG SectorSize;
  36     LARGE_INTEGER Offset = {{0, 0}};
  37     BOOLEAN DeviceError = FALSE;
  38     PAGED_CODE();
  39
  40     /* Get the I/O Stack and check the function type */
  41     Stack = IoGetCurrentIrpStackLocation(Irp);
  42     switch (Stack->MinorFunction)
  43     {
  44         case IRP_MN_MOUNT_VOLUME:
  45
  46             /* Assume failure */
  47             Status = STATUS_UNRECOGNIZED_VOLUME;
  48
  49             /* Get the device object and request the sector size */
  50             MountDevice = Stack->Parameters.MountVolume.DeviceObject;
  51             if (FsRecGetDeviceSectorSize(MountDevice, &SectorSize))
  52             {
  53                 /* Try to read the BPB */
  54                 if (FsRecReadBlock(MountDevice,
  55                                    &Offset,
  56                                    512,
  57                                    SectorSize,
  58                                    (PVOID)&Bpb,
  59                                    &DeviceError))
  60                 {
  61                     /* Check if it's an actual EXT2 volume */
  62                     if (FsRecIsExt2Volume(Bpb))
  63                     {
  64                         /* It is! */
  65                         Status = STATUS_FS_DRIVER_REQUIRED;
  66                     }
  67                 }
  68
  69                 /* Free the boot sector if we have one */
  70                 ExFreePool(Bpb);
  71             }
  72             else
  73             {
  74                 /* We have some sort of failure in the storage stack */
  75                 DeviceError = TRUE;
  76             }
  77
  78             /* Check if we have an error on the stack */
  79             if (DeviceError)
  80             {
  81                 /* Was this because of a floppy? */
  82                 if (MountDevice->Characteristics & FILE_FLOPPY_DISKETTE)
  83                 {
  84                     /* Let the FS try anyway */
  85                     Status = STATUS_FS_DRIVER_REQUIRED;
  86                 }
  87             }
  88
  89             break;
  90
  91         case IRP_MN_LOAD_FILE_SYSTEM:
  92
  93             /* Load the file system */
  94             Status = FsRecLoadFileSystem(DeviceObject,
  95                                          L"\\Registry\\Machine\\System\\CurrentControlSet\\Services\\Ext2");
  96             break;
  97
  98         default:
  99
 100             /* Invalid request */
 101             Status = STATUS_INVALID_DEVICE_REQUEST;
 102     }
 103
 104     /* Return Status */
 105     return Status;
 106 }
 107
 108 /* EOF */