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