FatPkg: Replace BSD License with BSD+Patent License

[mirror_edk2.git] / FatPkg / FatPei / Eltorito.c

/** @file\r
  Routines supporting partition discovery and\r
  logical device reading\r
\r
Copyright (c) 2006 - 2019, Intel Corporation. All rights reserved.<BR>\r
\r
SPDX-License-Identifier: BSD-2-Clause-Patent\r
\r
**/\r
\r
#include <IndustryStandard/ElTorito.h>\r
#include "FatLitePeim.h"\r
\r
/**\r
  This function finds Eltorito partitions. Main algorithm\r
  is ported from DXE partition driver.\r
\r
  @param[in]  PrivateData       The global memory map\r
  @param[in]  ParentBlockDevNo  The parent block device\r
\r
  @retval TRUE              New partitions are detected and logical block devices\r
                            are added to block device array\r
  @retval FALSE             No new partitions are added\r
\r
**/\r
BOOLEAN\r
FatFindEltoritoPartitions (\r
  IN  PEI_FAT_PRIVATE_DATA *PrivateData,\r
  IN  UINTN                ParentBlockDevNo\r
  )\r
{\r
  EFI_STATUS              Status;\r
  BOOLEAN                 Found;\r
  PEI_FAT_BLOCK_DEVICE    *BlockDev;\r
  PEI_FAT_BLOCK_DEVICE    *ParentBlockDev;\r
  UINT32                  VolDescriptorLba;\r
  UINT32                  Lba;\r
  CDROM_VOLUME_DESCRIPTOR *VolDescriptor;\r
  ELTORITO_CATALOG        *Catalog;\r
  UINTN                   Check;\r
  UINTN                   Index;\r
  UINTN                   MaxIndex;\r
  UINT16                  *CheckBuffer;\r
  UINT32                  SubBlockSize;\r
  UINT32                  SectorCount;\r
  UINT32                  VolSpaceSize;\r
\r
  if (ParentBlockDevNo > PEI_FAT_MAX_BLOCK_DEVICE - 1) {\r
    return FALSE;\r
  }\r
\r
  Found           = FALSE;\r
  ParentBlockDev  = &(PrivateData->BlockDevice[ParentBlockDevNo]);\r
  VolSpaceSize    = 0;\r
\r
  //\r
  // CD_ROM has the fixed block size as 2048 bytes\r
  //\r
  if (ParentBlockDev->BlockSize != 2048) {\r
    return FALSE;\r
  }\r
\r
  VolDescriptor = (CDROM_VOLUME_DESCRIPTOR *) PrivateData->BlockData;\r
  Catalog       = (ELTORITO_CATALOG *) VolDescriptor;\r
\r
  //\r
  // the ISO-9660 volume descriptor starts at 32k on the media\r
  // and CD_ROM has the fixed block size as 2048 bytes, so...\r
  //\r
  VolDescriptorLba = 15;\r
  //\r
  // ((16*2048) / Media->BlockSize) - 1;\r
  //\r
  // Loop: handle one volume descriptor per time\r
  //\r
  while (TRUE) {\r
\r
    VolDescriptorLba += 1;\r
    if (VolDescriptorLba > ParentBlockDev->LastBlock) {\r
      //\r
      // We are pointing past the end of the device so exit\r
      //\r
      break;\r
    }\r
\r
    Status = FatReadBlock (\r
              PrivateData,\r
              ParentBlockDevNo,\r
              VolDescriptorLba,\r
              ParentBlockDev->BlockSize,\r
              VolDescriptor\r
              );\r
    if (EFI_ERROR (Status)) {\r
      break;\r
    }\r
    //\r
    // Check for valid volume descriptor signature\r
    //\r
    if (VolDescriptor->Unknown.Type == CDVOL_TYPE_END ||\r
        CompareMem (VolDescriptor->Unknown.Id, CDVOL_ID, sizeof (VolDescriptor->Unknown.Id)) != 0\r
        ) {\r
      //\r
      // end of Volume descriptor list\r
      //\r
      break;\r
    }\r
    //\r
    // Read the Volume Space Size from Primary Volume Descriptor 81-88 byte\r
    //\r
    if (VolDescriptor->Unknown.Type == CDVOL_TYPE_CODED) {\r
      VolSpaceSize = VolDescriptor->PrimaryVolume.VolSpaceSize[1];\r
    }\r
    //\r
    // Is it an El Torito volume descriptor?\r
    //\r
    if (CompareMem (\r
          VolDescriptor->BootRecordVolume.SystemId,\r
          CDVOL_ELTORITO_ID,\r
          sizeof (CDVOL_ELTORITO_ID) - 1\r
          ) != 0) {\r
      continue;\r
    }\r
    //\r
    // Read in the boot El Torito boot catalog\r
    //\r
    Lba = UNPACK_INT32 (VolDescriptor->BootRecordVolume.EltCatalog);\r
    if (Lba > ParentBlockDev->LastBlock) {\r
      continue;\r
    }\r
\r
    Status = FatReadBlock (\r
              PrivateData,\r
              ParentBlockDevNo,\r
              Lba,\r
              ParentBlockDev->BlockSize,\r
              Catalog\r
              );\r
    if (EFI_ERROR (Status)) {\r
      continue;\r
    }\r
    //\r
    // We don't care too much about the Catalog header's contents, but we do want\r
    // to make sure it looks like a Catalog header\r
    //\r
    if (Catalog->Catalog.Indicator != ELTORITO_ID_CATALOG || Catalog->Catalog.Id55AA != 0xAA55) {\r
      continue;\r
    }\r
\r
    Check       = 0;\r
    CheckBuffer = (UINT16 *) Catalog;\r
    for (Index = 0; Index < sizeof (ELTORITO_CATALOG) / sizeof (UINT16); Index += 1) {\r
      Check += CheckBuffer[Index];\r
    }\r
\r
    if ((Check & 0xFFFF) != 0) {\r
      continue;\r
    }\r
\r
    MaxIndex = ParentBlockDev->BlockSize / sizeof (ELTORITO_CATALOG);\r
    for (Index = 1; Index < MaxIndex; Index += 1) {\r
      //\r
      // Next entry\r
      //\r
      Catalog += 1;\r
\r
      //\r
      // Check this entry\r
      //\r
      if (Catalog->Boot.Indicator != ELTORITO_ID_SECTION_BOOTABLE || Catalog->Boot.Lba == 0) {\r
        continue;\r
      }\r
\r
      SubBlockSize  = 512;\r
      SectorCount   = Catalog->Boot.SectorCount;\r
\r
      switch (Catalog->Boot.MediaType) {\r
\r
      case ELTORITO_NO_EMULATION:\r
        SubBlockSize  = ParentBlockDev->BlockSize;\r
        SectorCount   = Catalog->Boot.SectorCount;\r
        break;\r
\r
      case ELTORITO_HARD_DISK:\r
        break;\r
\r
      case ELTORITO_12_DISKETTE:\r
        SectorCount = 0x50 * 0x02 * 0x0F;\r
        break;\r
\r
      case ELTORITO_14_DISKETTE:\r
        SectorCount = 0x50 * 0x02 * 0x12;\r
        break;\r
\r
      case ELTORITO_28_DISKETTE:\r
        SectorCount = 0x50 * 0x02 * 0x24;\r
        break;\r
\r
      default:\r
        SectorCount   = 0;\r
        SubBlockSize  = ParentBlockDev->BlockSize;\r
        break;\r
      }\r
\r
      if (SectorCount < 2) {\r
        SectorCount = (VolSpaceSize > ParentBlockDev->LastBlock + 1) ? (UINT32) (ParentBlockDev->LastBlock - Catalog->Boot.Lba + 1) : (UINT32) (VolSpaceSize - Catalog->Boot.Lba);\r
      }\r
      //\r
      // Register this partition\r
      //\r
      if (PrivateData->BlockDeviceCount < PEI_FAT_MAX_BLOCK_DEVICE) {\r
\r
        Found                       = TRUE;\r
\r
        BlockDev                    = &(PrivateData->BlockDevice[PrivateData->BlockDeviceCount]);\r
\r
        BlockDev->BlockSize         = SubBlockSize;\r
        BlockDev->LastBlock         = SectorCount - 1;\r
        BlockDev->IoAlign           = ParentBlockDev->IoAlign;\r
        BlockDev->Logical           = TRUE;\r
        BlockDev->PartitionChecked  = FALSE;\r
        BlockDev->StartingPos       = MultU64x32 (Catalog->Boot.Lba, ParentBlockDev->BlockSize);\r
        BlockDev->ParentDevNo       = ParentBlockDevNo;\r
\r
        PrivateData->BlockDeviceCount++;\r
      }\r
    }\r
  }\r
\r
  ParentBlockDev->PartitionChecked = TRUE;\r
\r
  return Found;\r
\r
}\r