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