audk/EdkModulePkg/Universal/Disk/Partition/Dxe/ElTorito.c

284 lines
7.8 KiB
C

/*++
Copyright (c) 2006, Intel Corporation
All rights reserved. This program and the accompanying materials
are licensed and made available under the terms and conditions of the BSD License
which accompanies this distribution. The full text of the license may be found at
http://opensource.org/licenses/bsd-license.php
THE PROGRAM IS DISTRIBUTED UNDER THE BSD LICENSE ON AN "AS IS" BASIS,
WITHOUT WARRANTIES OR REPRESENTATIONS OF ANY KIND, EITHER EXPRESS OR IMPLIED.
Module Name:
ElTorito.c
Abstract:
Decode an El Torito formatted CD-ROM
Revision History
--*/
#include "Partition.h"
BOOLEAN
PartitionInstallElToritoChildHandles (
IN EFI_DRIVER_BINDING_PROTOCOL *This,
IN EFI_HANDLE Handle,
IN EFI_DISK_IO_PROTOCOL *DiskIo,
IN EFI_BLOCK_IO_PROTOCOL *BlockIo,
IN EFI_DEVICE_PATH_PROTOCOL *DevicePath
)
/*++
Routine Description:
Install child handles if the Handle supports El Torito format.
Arguments:
This - Calling context.
Handle - Parent Handle
DiskIo - Parent DiskIo interface
BlockIo - Parent BlockIo interface
DevicePath - Parent Device Path
Returns:
TRUE - some child handle(s) was added
FALSE - no child handle was added
--*/
{
EFI_STATUS Status;
UINT32 VolDescriptorLba;
UINT32 Lba;
EFI_BLOCK_IO_MEDIA *Media;
CDROM_VOLUME_DESCRIPTOR *VolDescriptor;
ELTORITO_CATALOG *Catalog;
UINTN Check;
UINTN Index;
UINTN BootEntry;
UINTN MaxIndex;
UINT16 *CheckBuffer;
CDROM_DEVICE_PATH CdDev;
UINT32 SubBlockSize;
UINT32 SectorCount;
BOOLEAN Found;
UINT32 VolSpaceSize;
Found = FALSE;
Media = BlockIo->Media;
VolSpaceSize = 0;
//
// CD_ROM has the fixed block size as 2048 bytes
//
if (Media->BlockSize != 2048) {
return FALSE;
}
VolDescriptor = AllocatePool ((UINTN) Media->BlockSize);
if (VolDescriptor == NULL) {
return FALSE;
}
Catalog = (ELTORITO_CATALOG *) VolDescriptor;
//
// the ISO-9660 volume descriptor starts at 32k on the media
// and CD_ROM has the fixed block size as 2048 bytes, so...
//
//
// ((16*2048) / Media->BlockSize) - 1;
//
VolDescriptorLba = 15;
//
// Loop: handle one volume descriptor per time
//
while (TRUE) {
VolDescriptorLba += 1;
if (VolDescriptorLba > Media->LastBlock) {
//
// We are pointing past the end of the device so exit
//
break;
}
Status = BlockIo->ReadBlocks (
BlockIo,
Media->MediaId,
VolDescriptorLba,
Media->BlockSize,
VolDescriptor
);
if (EFI_ERROR (Status)) {
break;
}
//
// Check for valid volume descriptor signature
//
if (VolDescriptor->Type == CDVOL_TYPE_END ||
CompareMem (VolDescriptor->Id, CDVOL_ID, sizeof (VolDescriptor->Id)) != 0
) {
//
// end of Volume descriptor list
//
break;
}
//
// Read the Volume Space Size from Primary Volume Descriptor 81-88 byte,
// the 32-bit numerical values is stored in Both-byte orders
//
if (VolDescriptor->Type == CDVOL_TYPE_CODED) {
VolSpaceSize = VolDescriptor->VolSpaceSize[0];
}
//
// Is it an El Torito volume descriptor?
//
if (CompareMem (VolDescriptor->SystemId, CDVOL_ELTORITO_ID, sizeof (CDVOL_ELTORITO_ID) - 1) != 0) {
continue;
}
//
// Read in the boot El Torito boot catalog
//
Lba = UNPACK_INT32 (VolDescriptor->EltCatalog);
if (Lba > Media->LastBlock) {
continue;
}
Status = BlockIo->ReadBlocks (
BlockIo,
Media->MediaId,
Lba,
Media->BlockSize,
Catalog
);
if (EFI_ERROR (Status)) {
DEBUG ((EFI_D_ERROR, "EltCheckDevice: error reading catalog %r\n", Status));
continue;
}
//
// We don't care too much about the Catalog header's contents, but we do want
// to make sure it looks like a Catalog header
//
if (Catalog->Catalog.Indicator != ELTORITO_ID_CATALOG || Catalog->Catalog.Id55AA != 0xAA55) {
DEBUG ((EFI_D_ERROR, "EltCheckBootCatalog: El Torito boot catalog header IDs not correct\n"));
continue;
}
Check = 0;
CheckBuffer = (UINT16 *) Catalog;
for (Index = 0; Index < sizeof (ELTORITO_CATALOG) / sizeof (UINT16); Index += 1) {
Check += CheckBuffer[Index];
}
if (Check & 0xFFFF) {
DEBUG ((EFI_D_ERROR, "EltCheckBootCatalog: El Torito boot catalog header checksum failed\n"));
continue;
}
MaxIndex = Media->BlockSize / sizeof (ELTORITO_CATALOG);
for (Index = 1, BootEntry = 1; Index < MaxIndex; Index += 1) {
//
// Next entry
//
Catalog += 1;
//
// Check this entry
//
if (Catalog->Boot.Indicator != ELTORITO_ID_SECTION_BOOTABLE || Catalog->Boot.Lba == 0) {
continue;
}
SubBlockSize = 512;
SectorCount = Catalog->Boot.SectorCount;
switch (Catalog->Boot.MediaType) {
case ELTORITO_NO_EMULATION:
SubBlockSize = Media->BlockSize;
break;
case ELTORITO_HARD_DISK:
break;
case ELTORITO_12_DISKETTE:
SectorCount = 0x50 * 0x02 * 0x0F;
break;
case ELTORITO_14_DISKETTE:
SectorCount = 0x50 * 0x02 * 0x12;
break;
case ELTORITO_28_DISKETTE:
SectorCount = 0x50 * 0x02 * 0x24;
break;
default:
DEBUG ((EFI_D_INIT, "EltCheckDevice: unsupported El Torito boot media type %x\n", Catalog->Boot.MediaType));
SectorCount = 0;
SubBlockSize = Media->BlockSize;
break;
}
//
// Create child device handle
//
CdDev.Header.Type = MEDIA_DEVICE_PATH;
CdDev.Header.SubType = MEDIA_CDROM_DP;
SetDevicePathNodeLength (&CdDev.Header, sizeof (CdDev));
if (Index == 1) {
//
// This is the initial/default entry
//
BootEntry = 0;
}
CdDev.BootEntry = (UINT32) BootEntry;
BootEntry++;
CdDev.PartitionStart = Catalog->Boot.Lba;
if (SectorCount < 2) {
//
// When the SectorCount < 2, set the Partition as the whole CD.
//
if (VolSpaceSize > (Media->LastBlock + 1)) {
CdDev.PartitionSize = (UINT32)(Media->LastBlock - Catalog->Boot.Lba + 1);
} else {
CdDev.PartitionSize = (UINT32)(VolSpaceSize - Catalog->Boot.Lba);
}
} else {
CdDev.PartitionSize = DivU64x32 (
MultU64x32 (
SectorCount,
SubBlockSize
) + Media->BlockSize - 1,
Media->BlockSize
);
}
Status = PartitionInstallChildHandle (
This,
Handle,
DiskIo,
BlockIo,
DevicePath,
(EFI_DEVICE_PATH_PROTOCOL *) &CdDev,
Catalog->Boot.Lba,
Catalog->Boot.Lba + CdDev.PartitionSize - 1,
SubBlockSize,
FALSE
);
if (!EFI_ERROR (Status)) {
Found = TRUE;
}
}
}
gBS->FreePool (VolDescriptor);
return Found;
}