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

   1 /*++
   2
   3 Copyright (c) 2006, Intel Corporation
   4 All rights reserved. This program and the accompanying materials
   5 are licensed and made available under the terms and conditions of the BSD License
   6 which accompanies this distribution.  The full text of the license may be found at
   7 http://opensource.org/licenses/bsd-license.php
   8
   9 THE PROGRAM IS DISTRIBUTED UNDER THE BSD LICENSE ON AN "AS IS" BASIS,
  10 WITHOUT WARRANTIES OR REPRESENTATIONS OF ANY KIND, EITHER EXPRESS OR IMPLIED.
  11
  12 Module Name:
  13
  14   ElTorito.c
  15
  16 Abstract:
  17
  18   Decode an El Torito formatted CD-ROM
  19
  20 Revision History
  21
  22 --*/
  23
  24 #include "Partition.h"
  25 #include "ElTorito.h"
  26
  27 BOOLEAN
  28 PartitionInstallElToritoChildHandles (
  29   IN  EFI_DRIVER_BINDING_PROTOCOL  *This,
  30   IN  EFI_HANDLE                   Handle,
  31   IN  EFI_DISK_IO_PROTOCOL         *DiskIo,
  32   IN  EFI_BLOCK_IO_PROTOCOL        *BlockIo,
  33   IN  EFI_DEVICE_PATH_PROTOCOL     *DevicePath
  34   )
  35 /*++
  36
  37 Routine Description:
  38   Install child handles if the Handle supports El Torito format.
  39
  40 Arguments:
  41   This       - Calling context.
  42   Handle     - Parent Handle
  43   DiskIo     - Parent DiskIo interface
  44   BlockIo    - Parent BlockIo interface
  45   DevicePath - Parent Device Path
  46
  47 Returns:
  48   TRUE       - some child handle(s) was added
  49   FALSE      - no child handle was added
  50
  51 --*/
  52 {
  53   EFI_STATUS              Status;
  54   UINT32                  VolDescriptorLba;
  55   UINT32                  Lba;
  56   EFI_BLOCK_IO_MEDIA      *Media;
  57   CDROM_VOLUME_DESCRIPTOR *VolDescriptor;
  58   ELTORITO_CATALOG        *Catalog;
  59   UINTN                   Check;
  60   UINTN                   Index;
  61   UINTN                   BootEntry;
  62   UINTN                   MaxIndex;
  63   UINT16                  *CheckBuffer;
  64   CDROM_DEVICE_PATH       CdDev;
  65   UINT32                  SubBlockSize;
  66   UINT32                  SectorCount;
  67   BOOLEAN                 Found;
  68   UINT32                  VolSpaceSize;
  69
  70   Found         = FALSE;
  71   Media         = BlockIo->Media;
  72   VolSpaceSize  = 0;
  73
  74   //
  75   // CD_ROM has the fixed block size as 2048 bytes
  76   //
  77   if (Media->BlockSize != 2048) {
  78     return FALSE;
  79   }
  80
  81   VolDescriptor = AllocatePool ((UINTN) Media->BlockSize);
  82
  83   if (VolDescriptor == NULL) {
  84     return FALSE;
  85   }
  86
  87   Catalog = (ELTORITO_CATALOG *) VolDescriptor;
  88
  89   //
  90   // the ISO-9660 volume descriptor starts at 32k on the media
  91   // and CD_ROM has the fixed block size as 2048 bytes, so...
  92   //
  93   //
  94   // ((16*2048) / Media->BlockSize) - 1;
  95   //
  96   VolDescriptorLba = 15;
  97   //
  98   // Loop: handle one volume descriptor per time
  99   //
 100   while (TRUE) {
 101
 102     VolDescriptorLba += 1;
 103     if (VolDescriptorLba > Media->LastBlock) {
 104       //
 105       // We are pointing past the end of the device so exit
 106       //
 107       break;
 108     }
 109
 110     Status = BlockIo->ReadBlocks (
 111                         BlockIo,
 112                         Media->MediaId,
 113                         VolDescriptorLba,
 114                         Media->BlockSize,
 115                         VolDescriptor
 116                         );
 117     if (EFI_ERROR (Status)) {
 118       break;
 119     }
 120     //
 121     // Check for valid volume descriptor signature
 122     //
 123     if (VolDescriptor->Type == CDVOL_TYPE_END ||
 124         CompareMem (VolDescriptor->Id, CDVOL_ID, sizeof (VolDescriptor->Id)) != 0
 125         ) {
 126       //
 127       // end of Volume descriptor list
 128       //
 129       break;
 130     }
 131     //
 132     // Read the Volume Space Size from Primary Volume Descriptor 81-88 byte,
 133     // the 32-bit numerical values is stored in Both-byte orders
 134     //
 135     if (VolDescriptor->Type == CDVOL_TYPE_CODED) {
 136       VolSpaceSize = VolDescriptor->VolSpaceSize[0];
 137     }
 138     //
 139     // Is it an El Torito volume descriptor?
 140     //
 141     if (CompareMem (VolDescriptor->SystemId, CDVOL_ELTORITO_ID, sizeof (CDVOL_ELTORITO_ID) - 1) != 0) {
 142       continue;
 143     }
 144     //
 145     // Read in the boot El Torito boot catalog
 146     //
 147     Lba = UNPACK_INT32 (VolDescriptor->EltCatalog);
 148     if (Lba > Media->LastBlock) {
 149       continue;
 150     }
 151
 152     Status = BlockIo->ReadBlocks (
 153                         BlockIo,
 154                         Media->MediaId,
 155                         Lba,
 156                         Media->BlockSize,
 157                         Catalog
 158                         );
 159     if (EFI_ERROR (Status)) {
 160       DEBUG ((EFI_D_ERROR, "EltCheckDevice: error reading catalog %r\n", Status));
 161       continue;
 162     }
 163     //
 164     // We don't care too much about the Catalog header's contents, but we do want
 165     // to make sure it looks like a Catalog header
 166     //
 167     if (Catalog->Catalog.Indicator != ELTORITO_ID_CATALOG || Catalog->Catalog.Id55AA != 0xAA55) {
 168       DEBUG ((EFI_D_ERROR, "EltCheckBootCatalog: El Torito boot catalog header IDs not correct\n"));
 169       continue;
 170     }
 171
 172     Check       = 0;
 173     CheckBuffer = (UINT16 *) Catalog;
 174     for (Index = 0; Index < sizeof (ELTORITO_CATALOG) / sizeof (UINT16); Index += 1) {
 175       Check += CheckBuffer[Index];
 176     }
 177
 178     if (Check & 0xFFFF) {
 179       DEBUG ((EFI_D_ERROR, "EltCheckBootCatalog: El Torito boot catalog header checksum failed\n"));
 180       continue;
 181     }
 182
 183     MaxIndex = Media->BlockSize / sizeof (ELTORITO_CATALOG);
 184     for (Index = 1, BootEntry = 1; Index < MaxIndex; Index += 1) {
 185       //
 186       // Next entry
 187       //
 188       Catalog += 1;
 189
 190       //
 191       // Check this entry
 192       //
 193       if (Catalog->Boot.Indicator != ELTORITO_ID_SECTION_BOOTABLE || Catalog->Boot.Lba == 0) {
 194         continue;
 195       }
 196
 197       SubBlockSize  = 512;
 198       SectorCount   = Catalog->Boot.SectorCount;
 199
 200       switch (Catalog->Boot.MediaType) {
 201
 202       case ELTORITO_NO_EMULATION:
 203         SubBlockSize = Media->BlockSize;
 204         break;
 205
 206       case ELTORITO_HARD_DISK:
 207         break;
 208
 209       case ELTORITO_12_DISKETTE:
 210         SectorCount = 0x50 * 0x02 * 0x0F;
 211         break;
 212
 213       case ELTORITO_14_DISKETTE:
 214         SectorCount = 0x50 * 0x02 * 0x12;
 215         break;
 216
 217       case ELTORITO_28_DISKETTE:
 218         SectorCount = 0x50 * 0x02 * 0x24;
 219         break;
 220
 221       default:
 222         DEBUG ((EFI_D_INIT, "EltCheckDevice: unsupported El Torito boot media type %x\n", Catalog->Boot.MediaType));
 223         SectorCount   = 0;
 224         SubBlockSize  = Media->BlockSize;
 225         break;
 226       }
 227       //
 228       // Create child device handle
 229       //
 230       CdDev.Header.Type     = MEDIA_DEVICE_PATH;
 231       CdDev.Header.SubType  = MEDIA_CDROM_DP;
 232       SetDevicePathNodeLength (&CdDev.Header, sizeof (CdDev));
 233
 234       if (Index == 1) {
 235         //
 236         // This is the initial/default entry
 237         //
 238         BootEntry = 0;
 239       }
 240
 241       CdDev.BootEntry = (UINT32) BootEntry;
 242       BootEntry++;
 243       CdDev.PartitionStart = Catalog->Boot.Lba;
 244       if (SectorCount < 2) {
 245         //
 246         // When the SectorCount < 2, set the Partition as the whole CD.
 247         //
 248         if (VolSpaceSize > (Media->LastBlock + 1)) {
 249           CdDev.PartitionSize = (UINT32)(Media->LastBlock - Catalog->Boot.Lba + 1);
 250         } else {
 251           CdDev.PartitionSize = (UINT32)(VolSpaceSize - Catalog->Boot.Lba);
 252         }
 253       } else {
 254         CdDev.PartitionSize = DivU64x32 (
 255                                 MultU64x32 (
 256                                   SectorCount,
 257                                   SubBlockSize
 258                                   ) + Media->BlockSize - 1,
 259                                 Media->BlockSize
 260                                 );
 261       }
 262
 263       Status = PartitionInstallChildHandle (
 264                 This,
 265                 Handle,
 266                 DiskIo,
 267                 BlockIo,
 268                 DevicePath,
 269                 (EFI_DEVICE_PATH_PROTOCOL *) &CdDev,
 270                 Catalog->Boot.Lba,
 271                 Catalog->Boot.Lba + CdDev.PartitionSize - 1,
 272                 SubBlockSize,
 273                 FALSE
 274                 );
 275       if (!EFI_ERROR (Status)) {
 276         Found = TRUE;
 277       }
 278     }
 279   }
 280
 281   gBS->FreePool (VolDescriptor);
 282
 283   return Found;
 284 }