diff options
Diffstat (limited to 'EDK/Foundation/Core/Dxe/FwVol/Ffs.c')
| -rw-r--r-- | EDK/Foundation/Core/Dxe/FwVol/Ffs.c | 266 |
1 files changed, 266 insertions, 0 deletions
diff --git a/EDK/Foundation/Core/Dxe/FwVol/Ffs.c b/EDK/Foundation/Core/Dxe/FwVol/Ffs.c new file mode 100644 index 0000000..3361ce2 --- /dev/null +++ b/EDK/Foundation/Core/Dxe/FwVol/Ffs.c @@ -0,0 +1,266 @@ +/*++ + +Copyright (c) 2004, 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: + + Ffs.c + +Abstract: + + FFS file access utilities. + +--*/ + + +#include "FwVolDriver.h" + +#define PHYSICAL_ADDRESS_TO_POINTER(Address) ((VOID *)((UINTN)(Address))) + + +EFI_FFS_FILE_STATE +GetFileState ( + IN UINT8 ErasePolarity, + IN EFI_FFS_FILE_HEADER *FfsHeader + ) +/*++ + +Routine Description: + Get the FFS file state by checking the highest bit set in the header's state field + +Arguments: + ErasePolarity - Erase polarity attribute of the firmware volume + FfsHeader - Points to the FFS file header + +Returns: + FFS File state + +--*/ +{ + EFI_FFS_FILE_STATE FileState; + UINT8 HighestBit; + + FileState = FfsHeader->State; + + if (ErasePolarity != 0) { + FileState = (EFI_FFS_FILE_STATE)~FileState; + } + + HighestBit = 0x80; + while (HighestBit != 0 && ((HighestBit & FileState) == 0)) { + HighestBit >>= 1; + } + + return (EFI_FFS_FILE_STATE)HighestBit; +} + + +BOOLEAN +IsBufferErased ( + IN UINT8 ErasePolarity, + IN VOID *InBuffer, + IN UINTN BufferSize + ) +/*++ + +Routine Description: + Check if a block of buffer is erased + +Arguments: + ErasePolarity - Erase polarity attribute of the firmware volume + InBuffer - The buffer to be checked + BufferSize - Size of the buffer in bytes + +Returns: + TRUE - The block of buffer is erased + FALSE - The block of buffer is not erased + +--*/ +{ + UINTN Count; + UINT8 EraseByte; + UINT8 *Buffer; + + if(ErasePolarity == 1) { + EraseByte = 0xFF; + } else { + EraseByte = 0; + } + + Buffer = InBuffer; + for (Count = 0; Count < BufferSize; Count++) { + if (Buffer[Count] != EraseByte) { + return FALSE; + } + } + + return TRUE; +} + + +BOOLEAN +VerifyFvHeaderChecksum ( + IN EFI_FIRMWARE_VOLUME_HEADER *FvHeader + ) +/*++ + +Routine Description: + Verify checksum of the firmware volume header + +Arguments: + FvHeader - Points to the firmware volume header to be checked + +Returns: + TRUE - Checksum verification passed + FALSE - Checksum verification failed + +--*/ +{ + UINT32 Index; + UINT32 HeaderLength; + UINT16 Checksum; + UINT16 *ptr; + + HeaderLength = FvHeader->HeaderLength; + ptr = (UINT16 *)FvHeader; + Checksum = 0; + + for (Index = 0; Index < HeaderLength / sizeof (UINT16); Index++) { + Checksum = (UINT16)(Checksum + ptr[Index]); + } + + if (Checksum == 0) { + return TRUE; + } else { + return FALSE; + } +} + + +BOOLEAN +VerifyHeaderChecksum ( + IN EFI_FFS_FILE_HEADER *FfsHeader + ) +/*++ + +Routine Description: + Verify checksum of the FFS file header + +Arguments: + FfsHeader - Points to the FFS file header to be checked + +Returns: + TRUE - Checksum verification passed + FALSE - Checksum verification failed + +--*/ +{ + UINT32 Index; + UINT8 *ptr; + UINT8 HeaderChecksum; + + ptr = (UINT8 *)FfsHeader; + HeaderChecksum = 0; + for (Index = 0; Index < sizeof(EFI_FFS_FILE_HEADER); Index++) { + HeaderChecksum = (UINT8)(HeaderChecksum + ptr[Index]); + } + + HeaderChecksum = HeaderChecksum - FfsHeader->State - FfsHeader->IntegrityCheck.Checksum.File; + + if (HeaderChecksum == 0) { + return TRUE; + } else { + return FALSE; + } +} + + +BOOLEAN +IsValidFfsHeader ( + IN UINT8 ErasePolarity, + IN EFI_FFS_FILE_HEADER *FfsHeader, + OUT EFI_FFS_FILE_STATE *FileState + ) +/*++ + +Routine Description: + Check if it's a valid FFS file header + +Arguments: + ErasePolarity - Erase polarity attribute of the firmware volume + FfsHeader - Points to the FFS file header to be checked + FileState - FFS file state to be returned + +Returns: + TRUE - Valid FFS file header + FALSE - Invalid FFS file header + +--*/ +{ + *FileState = GetFileState (ErasePolarity, FfsHeader); + + switch (*FileState) { + case EFI_FILE_HEADER_VALID: + case EFI_FILE_DATA_VALID: + case EFI_FILE_MARKED_FOR_UPDATE: + case EFI_FILE_DELETED: + // + // Here we need to verify header checksum + // + return VerifyHeaderChecksum (FfsHeader); + + case EFI_FILE_HEADER_CONSTRUCTION: + case EFI_FILE_HEADER_INVALID: + default: + return FALSE; + } +} + + +BOOLEAN +IsValidFfsFile ( + IN UINT8 ErasePolarity, + IN EFI_FFS_FILE_HEADER *FfsHeader + ) +/*++ + +Routine Description: + Check if it's a valid FFS file. + Here we are sure that it has a valid FFS file header since we must call IsValidFfsHeader() first. + +Arguments: + ErasePolarity - Erase polarity attribute of the firmware volume + FfsHeader - Points to the FFS file to be checked + +Returns: + TRUE - Valid FFS file + FALSE - Invalid FFS file + +--*/ +{ + EFI_FFS_FILE_STATE FileState; + + FileState = GetFileState (ErasePolarity, FfsHeader); + switch (FileState) { + + case EFI_FILE_DELETED: + case EFI_FILE_DATA_VALID: + case EFI_FILE_MARKED_FOR_UPDATE: + // + // Some other vliadation like file content checksum might be done here. + // For performance issue, Tiano only do FileState check. + // + return TRUE; + + default: + return FALSE; + } +} + |