/*++ 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: Gpt.c Abstract: Decode a hard disk partitioned with the GPT scheme in the EFI 1.0 specification. --*/ #include "Partition.h" STATIC BOOLEAN PartitionValidGptTable ( IN EFI_BLOCK_IO_PROTOCOL *BlockIo, IN EFI_DISK_IO_PROTOCOL *DiskIo, IN EFI_LBA Lba, OUT EFI_PARTITION_TABLE_HEADER *PartHeader ); STATIC BOOLEAN PartitionCheckGptEntryArrayCRC ( IN EFI_BLOCK_IO_PROTOCOL *BlockIo, IN EFI_DISK_IO_PROTOCOL *DiskIo, IN EFI_PARTITION_TABLE_HEADER *PartHeader ); STATIC BOOLEAN PartitionRestoreGptTable ( IN EFI_BLOCK_IO_PROTOCOL *BlockIo, IN EFI_DISK_IO_PROTOCOL *DiskIo, IN EFI_PARTITION_TABLE_HEADER *PartHeader ); STATIC VOID PartitionCheckGptEntry ( IN EFI_PARTITION_TABLE_HEADER *PartHeader, IN EFI_PARTITION_ENTRY *PartEntry, OUT EFI_PARTITION_ENTRY_STATUS *PEntryStatus ); STATIC BOOLEAN PartitionCheckCrcAltSize ( IN UINTN MaxSize, IN UINTN Size, IN OUT EFI_TABLE_HEADER *Hdr ); STATIC BOOLEAN PartitionCheckCrc ( IN UINTN MaxSize, IN OUT EFI_TABLE_HEADER *Hdr ); STATIC VOID PartitionSetCrcAltSize ( IN UINTN Size, IN OUT EFI_TABLE_HEADER *Hdr ); STATIC VOID PartitionSetCrc ( IN OUT EFI_TABLE_HEADER *Hdr ); EFI_STATUS PartitionInstallGptChildHandles ( 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 GPT partition structure. Arguments: This - Calling context. Handle - Parent Handle DiskIo - Parent DiskIo interface BlockIo - Parent BlockIo interface DevicePath - Parent Device Path Returns: EFI_SUCCESS - Valid GPT disk EFI_MEDIA_CHANGED - Media changed Detected !EFI_SUCCESS - Not a valid GPT disk --*/ { EFI_STATUS Status; UINT32 BlockSize; EFI_LBA LastBlock; MASTER_BOOT_RECORD *ProtectiveMbr; EFI_PARTITION_TABLE_HEADER *PrimaryHeader; EFI_PARTITION_TABLE_HEADER *BackupHeader; EFI_PARTITION_ENTRY *PartEntry; EFI_PARTITION_ENTRY_STATUS *PEntryStatus; UINTN Index; EFI_STATUS GptValid; HARDDRIVE_DEVICE_PATH HdDev; ProtectiveMbr = NULL; PrimaryHeader = NULL; BackupHeader = NULL; PartEntry = NULL; PEntryStatus = NULL; BlockSize = BlockIo->Media->BlockSize; LastBlock = BlockIo->Media->LastBlock; DEBUG ((EFI_D_INFO, " BlockSize : %d \n", BlockSize)); DEBUG ((EFI_D_INFO, " LastBlock : %x \n", LastBlock)); GptValid = EFI_NOT_FOUND; // // Allocate a buffer for the Protective MBR // ProtectiveMbr = AllocatePool (BlockSize); if (ProtectiveMbr == NULL) { return EFI_NOT_FOUND; } // // Read the Protective MBR from LBA #0 // Status = BlockIo->ReadBlocks ( BlockIo, BlockIo->Media->MediaId, 0, BlockIo->Media->BlockSize, ProtectiveMbr ); if (EFI_ERROR (Status)) { GptValid = Status; goto Done; } // // Verify that the Protective MBR is valid // if (ProtectiveMbr->Partition[0].BootIndicator != 0x00 || ProtectiveMbr->Partition[0].OSIndicator != PMBR_GPT_PARTITION || UNPACK_UINT32 (ProtectiveMbr->Partition[0].StartingLBA) != 1 ) { goto Done; } // // Allocate the GPT structures // PrimaryHeader = AllocateZeroPool (sizeof (EFI_PARTITION_TABLE_HEADER)); if (PrimaryHeader == NULL) { goto Done; } BackupHeader = AllocateZeroPool (sizeof (EFI_PARTITION_TABLE_HEADER)); if (BackupHeader == NULL) { goto Done; } // // Check primary and backup partition tables // if (!PartitionValidGptTable (BlockIo, DiskIo, PRIMARY_PART_HEADER_LBA, PrimaryHeader)) { DEBUG ((EFI_D_INFO, " Not Valid primary partition table\n")); if (!PartitionValidGptTable (BlockIo, DiskIo, LastBlock, BackupHeader)) { DEBUG ((EFI_D_INFO, " Not Valid backup partition table\n")); goto Done; } else { DEBUG ((EFI_D_INFO, " Valid backup partition table\n")); DEBUG ((EFI_D_INFO, " Restore primary partition table by the backup\n")); if (!PartitionRestoreGptTable (BlockIo, DiskIo, BackupHeader)) { DEBUG ((EFI_D_INFO, " Restore primary partition table error\n")); } if (PartitionValidGptTable (BlockIo, DiskIo, BackupHeader->AlternateLBA, PrimaryHeader)) { DEBUG ((EFI_D_INFO, " Restore backup partition table success\n")); } } } else if (!PartitionValidGptTable (BlockIo, DiskIo, PrimaryHeader->AlternateLBA, BackupHeader)) { DEBUG ((EFI_D_INFO, " Valid primary and !Valid backup partition table\n")); DEBUG ((EFI_D_INFO, " Restore backup partition table by the primary\n")); if (!PartitionRestoreGptTable (BlockIo, DiskIo, PrimaryHeader)) { DEBUG ((EFI_D_INFO, " Restore backup partition table error\n")); } if (PartitionValidGptTable (BlockIo, DiskIo, PrimaryHeader->AlternateLBA, BackupHeader)) { DEBUG ((EFI_D_INFO, " Restore backup partition table success\n")); } } DEBUG ((EFI_D_INFO, " Valid primary and Valid backup partition table\n")); // // Read the EFI Partition Entries // PartEntry = AllocatePool (PrimaryHeader->NumberOfPartitionEntries * sizeof (EFI_PARTITION_ENTRY)); if (PartEntry == NULL) { DEBUG ((EFI_D_ERROR, "Allocate pool error\n")); goto Done; } Status = DiskIo->ReadDisk ( DiskIo, BlockIo->Media->MediaId, MultU64x32(PrimaryHeader->PartitionEntryLBA, BlockSize), PrimaryHeader->NumberOfPartitionEntries * (PrimaryHeader->SizeOfPartitionEntry), PartEntry ); if (EFI_ERROR (Status)) { GptValid = Status; DEBUG ((EFI_D_INFO, " Partition Entry ReadBlocks error\n")); goto Done; } DEBUG ((EFI_D_INFO, " Partition entries read block success\n")); DEBUG ((EFI_D_INFO, " Number of partition entries: %d\n", PrimaryHeader->NumberOfPartitionEntries)); PEntryStatus = AllocateZeroPool (PrimaryHeader->NumberOfPartitionEntries * sizeof (EFI_PARTITION_ENTRY_STATUS)); if (PEntryStatus == NULL) { DEBUG ((EFI_D_ERROR, "Allocate pool error\n")); goto Done; } // // Check the integrity of partition entries // PartitionCheckGptEntry (PrimaryHeader, PartEntry, PEntryStatus); // // If we got this far the GPT layout of the disk is valid and we should return true // GptValid = EFI_SUCCESS; // // Create child device handles // for (Index = 0; Index < PrimaryHeader->NumberOfPartitionEntries; Index++) { if (CompareGuid (&PartEntry[Index].PartitionTypeGUID, &gEfiPartTypeUnusedGuid) || PEntryStatus[Index].OutOfRange || PEntryStatus[Index].Overlap ) { // // Don't use null EFI Partition Entries or Invalid Partition Entries // continue; } ZeroMem (&HdDev, sizeof (HdDev)); HdDev.Header.Type = MEDIA_DEVICE_PATH; HdDev.Header.SubType = MEDIA_HARDDRIVE_DP; SetDevicePathNodeLength (&HdDev.Header, sizeof (HdDev)); HdDev.PartitionNumber = (UINT32) Index + 1; HdDev.MBRType = MBR_TYPE_EFI_PARTITION_TABLE_HEADER; HdDev.SignatureType = SIGNATURE_TYPE_GUID; HdDev.PartitionStart = PartEntry[Index].StartingLBA; HdDev.PartitionSize = PartEntry[Index].EndingLBA - PartEntry[Index].StartingLBA + 1; CopyMem (HdDev.Signature, &PartEntry[Index].UniquePartitionGUID, sizeof (EFI_GUID)); DEBUG ((EFI_D_INFO, " Index : %d\n", Index)); DEBUG ((EFI_D_INFO, " Start LBA : %x\n", HdDev.PartitionStart)); DEBUG ((EFI_D_INFO, " End LBA : %x\n", PartEntry[Index].EndingLBA)); DEBUG ((EFI_D_INFO, " Partition size: %x\n", HdDev.PartitionSize)); DEBUG ((EFI_D_INFO, " Start : %x", MultU64x32 (PartEntry[Index].StartingLBA, BlockSize))); DEBUG ((EFI_D_INFO, " End : %x\n", MultU64x32 (PartEntry[Index].EndingLBA, BlockSize))); Status = PartitionInstallChildHandle ( This, Handle, DiskIo, BlockIo, DevicePath, (EFI_DEVICE_PATH_PROTOCOL *) &HdDev, PartEntry[Index].StartingLBA, PartEntry[Index].EndingLBA, BlockSize, CompareGuid(&PartEntry[Index].PartitionTypeGUID, &gEfiPartTypeSystemPartGuid) ); } DEBUG ((EFI_D_INFO, "Prepare to Free Pool\n")); Done: if (ProtectiveMbr != NULL) { FreePool (ProtectiveMbr); } if (PrimaryHeader != NULL) { FreePool (PrimaryHeader); } if (BackupHeader != NULL) { FreePool (BackupHeader); } if (PartEntry != NULL) { FreePool (PartEntry); } if (PEntryStatus != NULL) { FreePool (PEntryStatus); } return GptValid; } STATIC BOOLEAN PartitionValidGptTable ( IN EFI_BLOCK_IO_PROTOCOL *BlockIo, IN EFI_DISK_IO_PROTOCOL *DiskIo, IN EFI_LBA Lba, OUT EFI_PARTITION_TABLE_HEADER *PartHeader ) /*++ Routine Description: Check if the GPT partition table is valid Arguments: BlockIo - Parent BlockIo interface DiskIo - Disk Io protocol. Lba - The starting Lba of the Partition Table PartHeader - Stores the partition table that is read Returns: TRUE - The partition table is valid FALSE - The partition table is not valid --*/ { EFI_STATUS Status; UINT32 BlockSize; EFI_PARTITION_TABLE_HEADER *PartHdr; BlockSize = BlockIo->Media->BlockSize; PartHdr = AllocateZeroPool (BlockSize); if (PartHdr == NULL) { DEBUG ((EFI_D_ERROR, "Allocate pool error\n")); return FALSE; } // // Read the EFI Partition Table Header // Status = BlockIo->ReadBlocks ( BlockIo, BlockIo->Media->MediaId, Lba, BlockSize, PartHdr ); if (EFI_ERROR (Status)) { FreePool (PartHdr); return FALSE; } if (CompareMem (&PartHdr->Header.Signature, EFI_PTAB_HEADER_ID, sizeof (UINT64)) != 0 || !PartitionCheckCrc (BlockSize, &PartHdr->Header) || PartHdr->MyLBA != Lba ) { DEBUG ((EFI_D_INFO, " !Valid efi partition table header\n")); FreePool (PartHdr); return FALSE; } CopyMem (PartHeader, PartHdr, sizeof (EFI_PARTITION_TABLE_HEADER)); if (!PartitionCheckGptEntryArrayCRC (BlockIo, DiskIo, PartHeader)) { FreePool (PartHdr); return FALSE; } DEBUG ((EFI_D_INFO, " Valid efi partition table header\n")); FreePool (PartHdr); return TRUE; } STATIC BOOLEAN PartitionCheckGptEntryArrayCRC ( IN EFI_BLOCK_IO_PROTOCOL *BlockIo, IN EFI_DISK_IO_PROTOCOL *DiskIo, IN EFI_PARTITION_TABLE_HEADER *PartHeader ) /*++ Routine Description: Check if the CRC field in the Partition table header is valid for Partition entry array Arguments: BlockIo - parent BlockIo interface DiskIo - Disk Io Protocol. PartHeader - Partition table header structure Returns: TRUE - the CRC is valid FALSE - the CRC is invalid --*/ { EFI_STATUS Status; UINT8 *Ptr; UINT32 Crc; UINTN Size; // // Read the EFI Partition Entries // Ptr = AllocatePool (PartHeader->NumberOfPartitionEntries * PartHeader->SizeOfPartitionEntry); if (Ptr == NULL) { DEBUG ((EFI_D_ERROR, " Allocate pool error\n")); return FALSE; } Status = DiskIo->ReadDisk ( DiskIo, BlockIo->Media->MediaId, MultU64x32(PartHeader->PartitionEntryLBA, BlockIo->Media->BlockSize), PartHeader->NumberOfPartitionEntries * PartHeader->SizeOfPartitionEntry, Ptr ); if (EFI_ERROR (Status)) { FreePool (Ptr); return FALSE; } Size = PartHeader->NumberOfPartitionEntries * PartHeader->SizeOfPartitionEntry; Status = gBS->CalculateCrc32 (Ptr, Size, &Crc); if (EFI_ERROR (Status)) { DEBUG ((EFI_D_ERROR, "CheckPEntryArrayCRC: Crc calculation failed\n")); FreePool (Ptr); return FALSE; } FreePool (Ptr); return (BOOLEAN) (PartHeader->PartitionEntryArrayCRC32 == Crc); } STATIC BOOLEAN PartitionRestoreGptTable ( IN EFI_BLOCK_IO_PROTOCOL *BlockIo, IN EFI_DISK_IO_PROTOCOL *DiskIo, IN EFI_PARTITION_TABLE_HEADER *PartHeader ) /*++ Routine Description: Restore Partition Table to its alternate place (Primary -> Backup or Backup -> Primary) Arguments: BlockIo - parent BlockIo interface DiskIo - Disk Io Protocol. PartHeader - the source Partition table header structure Returns: TRUE - Restoring succeeds FALSE - Restoring failed --*/ { EFI_STATUS Status; UINTN BlockSize; EFI_PARTITION_TABLE_HEADER *PartHdr; EFI_LBA PEntryLBA; UINT8 *Ptr; PartHdr = NULL; Ptr = NULL; BlockSize = BlockIo->Media->BlockSize; PartHdr = AllocateZeroPool (BlockSize); if (PartHdr == NULL) { DEBUG ((EFI_D_ERROR, "Allocate pool error\n")); return FALSE; } PEntryLBA = (PartHeader->MyLBA == PRIMARY_PART_HEADER_LBA) ? \ (PartHeader->LastUsableLBA + 1) : \ (PRIMARY_PART_HEADER_LBA + 1); CopyMem (PartHdr, PartHeader, sizeof (EFI_PARTITION_TABLE_HEADER)); PartHdr->MyLBA = PartHeader->AlternateLBA; PartHdr->AlternateLBA = PartHeader->MyLBA; PartHdr->PartitionEntryLBA = PEntryLBA; PartitionSetCrc ((EFI_TABLE_HEADER *) PartHdr); Status = BlockIo->WriteBlocks (BlockIo, BlockIo->Media->MediaId, PartHdr->MyLBA, BlockSize, PartHdr); if (EFI_ERROR (Status)) { goto Done; } Ptr = AllocatePool (PartHeader->NumberOfPartitionEntries * PartHeader->SizeOfPartitionEntry); if (Ptr == NULL) { DEBUG ((EFI_D_ERROR, " Allocate pool effor\n")); Status = EFI_OUT_OF_RESOURCES; goto Done; } Status = DiskIo->ReadDisk ( DiskIo, BlockIo->Media->MediaId, MultU64x32(PartHeader->PartitionEntryLBA, BlockIo->Media->BlockSize), PartHeader->NumberOfPartitionEntries * PartHeader->SizeOfPartitionEntry, Ptr ); if (EFI_ERROR (Status)) { goto Done; } Status = DiskIo->WriteDisk ( DiskIo, BlockIo->Media->MediaId, MultU64x32(PEntryLBA, BlockIo->Media->BlockSize), PartHeader->NumberOfPartitionEntries * PartHeader->SizeOfPartitionEntry, Ptr ); Done: FreePool (PartHdr); FreePool (Ptr); if (EFI_ERROR (Status)) { return FALSE; } return TRUE; } STATIC VOID PartitionCheckGptEntry ( IN EFI_PARTITION_TABLE_HEADER *PartHeader, IN EFI_PARTITION_ENTRY *PartEntry, OUT EFI_PARTITION_ENTRY_STATUS *PEntryStatus ) /*++ Routine Description: Check each partition entry for its range Arguments: PartHeader - the partition table header PartEntry - the partition entry array PEntryStatus - the partition entry status array recording the status of each partition Returns: VOID --*/ { EFI_LBA StartingLBA; EFI_LBA EndingLBA; UINTN Index1; UINTN Index2; DEBUG ((EFI_D_INFO, " start check partition entries\n")); for (Index1 = 0; Index1 < PartHeader->NumberOfPartitionEntries; Index1++) { if (CompareGuid (&PartEntry[Index1].PartitionTypeGUID, &gEfiPartTypeUnusedGuid)) { continue; } StartingLBA = PartEntry[Index1].StartingLBA; EndingLBA = PartEntry[Index1].EndingLBA; if (StartingLBA > EndingLBA || StartingLBA < PartHeader->FirstUsableLBA || StartingLBA > PartHeader->LastUsableLBA || EndingLBA < PartHeader->FirstUsableLBA || EndingLBA > PartHeader->LastUsableLBA ) { PEntryStatus[Index1].OutOfRange = TRUE; continue; } for (Index2 = Index1 + 1; Index2 < PartHeader->NumberOfPartitionEntries; Index2++) { if (CompareGuid (&PartEntry[Index2].PartitionTypeGUID, &gEfiPartTypeUnusedGuid)) { continue; } if (PartEntry[Index2].EndingLBA >= StartingLBA && PartEntry[Index2].StartingLBA <= EndingLBA) { // // This region overlaps with the Index1'th region // PEntryStatus[Index1].Overlap = TRUE; PEntryStatus[Index2].Overlap = TRUE; continue; } } } DEBUG ((EFI_D_INFO, " End check partition entries\n")); } STATIC VOID PartitionSetCrc ( IN OUT EFI_TABLE_HEADER *Hdr ) /*++ Routine Description: Updates the CRC32 value in the table header Arguments: Hdr - The table to update Returns: None --*/ { PartitionSetCrcAltSize (Hdr->HeaderSize, Hdr); } STATIC VOID PartitionSetCrcAltSize ( IN UINTN Size, IN OUT EFI_TABLE_HEADER *Hdr ) /*++ Routine Description: Updates the CRC32 value in the table header Arguments: Size - The size of the table Hdr - The table to update Returns: None --*/ { UINT32 Crc; Hdr->CRC32 = 0; gBS->CalculateCrc32 ((UINT8 *) Hdr, Size, &Crc); Hdr->CRC32 = Crc; } STATIC BOOLEAN PartitionCheckCrc ( IN UINTN MaxSize, IN OUT EFI_TABLE_HEADER *Hdr ) /*++ Routine Description: Checks the CRC32 value in the table header Arguments: MaxSize - Max Size limit Hdr - The table to check Returns: TRUE if the CRC is OK in the table --*/ { return PartitionCheckCrcAltSize (MaxSize, Hdr->HeaderSize, Hdr); } STATIC BOOLEAN PartitionCheckCrcAltSize ( IN UINTN MaxSize, IN UINTN Size, IN OUT EFI_TABLE_HEADER *Hdr ) /*++ Routine Description: Checks the CRC32 value in the table header Arguments: MaxSize - Max Size Limit Size - The size of the table Hdr - The table to check Returns: TRUE if the CRC is OK in the table --*/ { UINT32 Crc; UINT32 OrgCrc; EFI_STATUS Status; Crc = 0; if (Size == 0) { // // If header size is 0 CRC will pass so return FALSE here // return FALSE; } if (MaxSize && Size > MaxSize) { DEBUG ((EFI_D_ERROR, "CheckCrc32: Size > MaxSize\n")); return FALSE; } // // clear old crc from header // OrgCrc = Hdr->CRC32; Hdr->CRC32 = 0; Status = gBS->CalculateCrc32 ((UINT8 *) Hdr, Size, &Crc); if (EFI_ERROR (Status)) { DEBUG ((EFI_D_ERROR, "CheckCrc32: Crc calculation failed\n")); return FALSE; } // // set results // Hdr->CRC32 = Crc; // // return status // DEBUG_CODE_BEGIN (); if (OrgCrc != Crc) { DEBUG ((EFI_D_ERROR, "CheckCrc32: Crc check failed\n")); } DEBUG_CODE_END (); return (BOOLEAN) (OrgCrc == Crc); }