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audk/OvmfPkg/Tcg/TdTcg2Dxe/MeasureBootPeCoff.c

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/** @file
This module implements measuring PeCoff image for Tcg2 Protocol.
Caution: This file requires additional review when modified.
This driver will have external input - PE/COFF image.
This external input must be validated carefully to avoid security issue like
buffer overflow, integer overflow.
Copyright (c) 2015 - 2018, Intel Corporation. All rights reserved.<BR>
SPDX-License-Identifier: BSD-2-Clause-Patent
**/
#include <PiDxe.h>
#include <Library/BaseLib.h>
#include <Library/DebugLib.h>
#include <Library/BaseMemoryLib.h>
#include <Library/MemoryAllocationLib.h>
#include <Library/DevicePathLib.h>
#include <Library/UefiBootServicesTableLib.h>
#include <Library/UefiImageLib.h>
#include <Library/HashLib.h>
UINTN mTcg2DxeImageSize = 0;
typedef union {
EFI_IMAGE_NT_HEADERS32 *Pe32;
EFI_IMAGE_NT_HEADERS64 *Pe32Plus;
EFI_IMAGE_OPTIONAL_HEADER_UNION *Union;
} EFI_IMAGE_OPTIONAL_HEADER_PTR_UNION;
/**
Reads contents of a PE/COFF image in memory buffer.
Caution: This function may receive untrusted input.
PE/COFF image is external input, so this function will make sure the PE/COFF image content
read is within the image buffer.
@param FileHandle Pointer to the file handle to read the PE/COFF image.
@param FileOffset Offset into the PE/COFF image to begin the read operation.
@param ReadSize On input, the size in bytes of the requested read operation.
On output, the number of bytes actually read.
@param Buffer Output buffer that contains the data read from the PE/COFF image.
@retval EFI_SUCCESS The specified portion of the PE/COFF image was read and the size
**/
EFI_STATUS
EFIAPI
Tcg2DxeImageRead (
IN VOID *FileHandle,
IN UINTN FileOffset,
IN OUT UINTN *ReadSize,
OUT VOID *Buffer
)
{
UINTN EndPosition;
if ((FileHandle == NULL) || (ReadSize == NULL) || (Buffer == NULL)) {
return EFI_INVALID_PARAMETER;
}
if (MAX_ADDRESS - FileOffset < *ReadSize) {
return EFI_INVALID_PARAMETER;
}
EndPosition = FileOffset + *ReadSize;
if (EndPosition > mTcg2DxeImageSize) {
*ReadSize = (UINT32)(mTcg2DxeImageSize - FileOffset);
}
if (FileOffset >= mTcg2DxeImageSize) {
*ReadSize = 0;
}
CopyMem (Buffer, (UINT8 *)((UINTN)FileHandle + FileOffset), *ReadSize);
return EFI_SUCCESS;
}
/**
Measure PE image into TPM log based on the authenticode image hashing in
PE/COFF Specification 8.0 Appendix A.
Caution: This function may receive untrusted input.
PE/COFF image is external input, so this function will validate its data structure
within this image buffer before use.
Notes: PE/COFF image is checked by BasePeCoffLib PeCoffLoaderGetImageInfo().
@param[in] RtmrIndex Rtmr index
@param[in] ImageAddress Start address of image buffer.
@param[in] ImageSize Image size
@param[out] DigestList Digest list of this image.
@retval EFI_SUCCESS Successfully measure image.
@retval EFI_OUT_OF_RESOURCES No enough resource to measure image.
@retval other error value
**/
EFI_STATUS
MeasurePeImageAndExtend (
IN UINT32 RtmrIndex,
IN EFI_PHYSICAL_ADDRESS ImageAddress,
IN UINTN ImageSize,
OUT TPML_DIGEST_VALUES *DigestList
)
{
EFI_STATUS Status;
EFI_IMAGE_DOS_HEADER *DosHdr;
UINT32 PeCoffHeaderOffset;
EFI_IMAGE_SECTION_HEADER *Section;
UINT8 *HashBase;
UINTN HashSize;
UINTN SumOfBytesHashed;
EFI_IMAGE_SECTION_HEADER *SectionHeader;
UINTN Index;
UINTN Pos;
EFI_IMAGE_OPTIONAL_HEADER_PTR_UNION Hdr;
UINT32 NumberOfRvaAndSizes;
UINT32 CertSize;
HASH_HANDLE HashHandle;
UEFI_IMAGE_LOADER_IMAGE_CONTEXT ImageContext;
HashHandle = 0xFFFFFFFF; // Know bad value
Status = EFI_UNSUPPORTED;
SectionHeader = NULL;
mTcg2DxeImageSize = ImageSize;
//
// Get information about the image being loaded
//
Status = UefiImageInitializeContext (&ImageContext, (VOID *) (UINTN) ImageAddress, ImageSize);
if (EFI_ERROR (Status)) {
//
// The information can't be got from the invalid PeImage
//
DEBUG ((DEBUG_INFO, "Tcg2Dxe: PeImage invalid. Cannot retrieve image information.\n"));
goto Finish;
}
DosHdr = (EFI_IMAGE_DOS_HEADER *)(UINTN)ImageAddress;
PeCoffHeaderOffset = 0;
if (DosHdr->e_magic == EFI_IMAGE_DOS_SIGNATURE) {
PeCoffHeaderOffset = DosHdr->e_lfanew;
}
Hdr.Pe32 = (EFI_IMAGE_NT_HEADERS32 *)((UINT8 *)(UINTN)ImageAddress + PeCoffHeaderOffset);
if (Hdr.Pe32->CommonHeader.Signature != EFI_IMAGE_NT_SIGNATURE) {
Status = EFI_UNSUPPORTED;
goto Finish;
}
//
// PE/COFF Image Measurement
//
// NOTE: The following codes/steps are based upon the authenticode image hashing in
// PE/COFF Specification 8.0 Appendix A.
//
//
// 1. Load the image header into memory.
// 2. Initialize a SHA hash context.
Status = HashStart (&HashHandle);
if (EFI_ERROR (Status)) {
goto Finish;
}
//
// Measuring PE/COFF Image Header;
// But CheckSum field and SECURITY data directory (certificate) are excluded
//
//
// 3. Calculate the distance from the base of the image header to the image checksum address.
// 4. Hash the image header from its base to beginning of the image checksum.
//
HashBase = (UINT8 *)(UINTN)ImageAddress;
if (Hdr.Pe32->Magic == EFI_IMAGE_NT_OPTIONAL_HDR32_MAGIC) {
//
// Use PE32 offset
//
NumberOfRvaAndSizes = Hdr.Pe32->NumberOfRvaAndSizes;
HashSize = (UINTN)(&Hdr.Pe32->CheckSum) - (UINTN)HashBase;
} else {
//
// Use PE32+ offset
//
NumberOfRvaAndSizes = Hdr.Pe32Plus->NumberOfRvaAndSizes;
HashSize = (UINTN)(&Hdr.Pe32Plus->CheckSum) - (UINTN)HashBase;
}
Status = HashUpdate (HashHandle, HashBase, HashSize);
if (EFI_ERROR (Status)) {
goto Finish;
}
//
// 5. Skip over the image checksum (it occupies a single ULONG).
//
if (NumberOfRvaAndSizes <= EFI_IMAGE_DIRECTORY_ENTRY_SECURITY) {
//
// 6. Since there is no Cert Directory in optional header, hash everything
// from the end of the checksum to the end of image header.
//
if (Hdr.Pe32->Magic == EFI_IMAGE_NT_OPTIONAL_HDR32_MAGIC) {
//
// Use PE32 offset.
//
HashBase = (UINT8 *)&Hdr.Pe32->CheckSum + sizeof (UINT32);
HashSize = Hdr.Pe32->SizeOfHeaders - (UINTN)(HashBase - ImageAddress);
} else {
//
// Use PE32+ offset.
//
HashBase = (UINT8 *)&Hdr.Pe32Plus->CheckSum + sizeof (UINT32);
HashSize = Hdr.Pe32Plus->SizeOfHeaders - (UINTN)(HashBase - ImageAddress);
}
if (HashSize != 0) {
Status = HashUpdate (HashHandle, HashBase, HashSize);
if (EFI_ERROR (Status)) {
goto Finish;
}
}
} else {
//
// 7. Hash everything from the end of the checksum to the start of the Cert Directory.
//
if (Hdr.Pe32->Magic == EFI_IMAGE_NT_OPTIONAL_HDR32_MAGIC) {
//
// Use PE32 offset
//
HashBase = (UINT8 *)&Hdr.Pe32->CheckSum + sizeof (UINT32);
HashSize = (UINTN)(&Hdr.Pe32->DataDirectory[EFI_IMAGE_DIRECTORY_ENTRY_SECURITY]) - (UINTN)HashBase;
} else {
//
// Use PE32+ offset
//
HashBase = (UINT8 *)&Hdr.Pe32Plus->CheckSum + sizeof (UINT32);
HashSize = (UINTN)(&Hdr.Pe32Plus->DataDirectory[EFI_IMAGE_DIRECTORY_ENTRY_SECURITY]) - (UINTN)HashBase;
}
if (HashSize != 0) {
Status = HashUpdate (HashHandle, HashBase, HashSize);
if (EFI_ERROR (Status)) {
goto Finish;
}
}
//
// 8. Skip over the Cert Directory. (It is sizeof(IMAGE_DATA_DIRECTORY) bytes.)
// 9. Hash everything from the end of the Cert Directory to the end of image header.
//
if (Hdr.Pe32->Magic == EFI_IMAGE_NT_OPTIONAL_HDR32_MAGIC) {
//
// Use PE32 offset
//
HashBase = (UINT8 *)&Hdr.Pe32->DataDirectory[EFI_IMAGE_DIRECTORY_ENTRY_SECURITY + 1];
HashSize = Hdr.Pe32->SizeOfHeaders - (UINTN)(HashBase - ImageAddress);
} else {
//
// Use PE32+ offset
//
HashBase = (UINT8 *)&Hdr.Pe32Plus->DataDirectory[EFI_IMAGE_DIRECTORY_ENTRY_SECURITY + 1];
HashSize = Hdr.Pe32Plus->SizeOfHeaders - (UINTN)(HashBase - ImageAddress);
}
if (HashSize != 0) {
Status = HashUpdate (HashHandle, HashBase, HashSize);
if (EFI_ERROR (Status)) {
goto Finish;
}
}
}
//
// 10. Set the SUM_OF_BYTES_HASHED to the size of the header
//
if (Hdr.Pe32->Magic == EFI_IMAGE_NT_OPTIONAL_HDR32_MAGIC) {
//
// Use PE32 offset
//
SumOfBytesHashed = Hdr.Pe32->SizeOfHeaders;
} else {
//
// Use PE32+ offset
//
SumOfBytesHashed = Hdr.Pe32Plus->SizeOfHeaders;
}
//
// 11. Build a temporary table of pointers to all the IMAGE_SECTION_HEADER
// structures in the image. The 'NumberOfSections' field of the image
// header indicates how big the table should be. Do not include any
// IMAGE_SECTION_HEADERs in the table whose 'SizeOfRawData' field is zero.
//
SectionHeader = (EFI_IMAGE_SECTION_HEADER *)AllocateZeroPool (sizeof (EFI_IMAGE_SECTION_HEADER) * Hdr.Pe32->CommonHeader.FileHeader.NumberOfSections);
if (SectionHeader == NULL) {
Status = EFI_OUT_OF_RESOURCES;
goto Finish;
}
//
// 12. Using the 'PointerToRawData' in the referenced section headers as
// a key, arrange the elements in the table in ascending order. In other
// words, sort the section headers according to the disk-file offset of
// the section.
//
Section = (EFI_IMAGE_SECTION_HEADER *)(
(UINT8 *)(UINTN)ImageAddress +
PeCoffHeaderOffset +
sizeof (UINT32) +
sizeof (EFI_IMAGE_FILE_HEADER) +
Hdr.Pe32->CommonHeader.FileHeader.SizeOfOptionalHeader
);
for (Index = 0; Index < Hdr.Pe32->CommonHeader.FileHeader.NumberOfSections; Index++) {
Pos = Index;
while ((Pos > 0) && (Section->PointerToRawData < SectionHeader[Pos - 1].PointerToRawData)) {
CopyMem (&SectionHeader[Pos], &SectionHeader[Pos - 1], sizeof (EFI_IMAGE_SECTION_HEADER));
Pos--;
}
CopyMem (&SectionHeader[Pos], Section, sizeof (EFI_IMAGE_SECTION_HEADER));
Section += 1;
}
//
// 13. Walk through the sorted table, bring the corresponding section
// into memory, and hash the entire section (using the 'SizeOfRawData'
// field in the section header to determine the amount of data to hash).
// 14. Add the section's 'SizeOfRawData' to SUM_OF_BYTES_HASHED .
// 15. Repeat steps 13 and 14 for all the sections in the sorted table.
//
for (Index = 0; Index < Hdr.Pe32->CommonHeader.FileHeader.NumberOfSections; Index++) {
Section = (EFI_IMAGE_SECTION_HEADER *)&SectionHeader[Index];
if (Section->SizeOfRawData == 0) {
continue;
}
HashBase = (UINT8 *)(UINTN)ImageAddress + Section->PointerToRawData;
HashSize = (UINTN)Section->SizeOfRawData;
Status = HashUpdate (HashHandle, HashBase, HashSize);
if (EFI_ERROR (Status)) {
goto Finish;
}
SumOfBytesHashed += HashSize;
}
//
// 16. If the file size is greater than SUM_OF_BYTES_HASHED, there is extra
// data in the file that needs to be added to the hash. This data begins
// at file offset SUM_OF_BYTES_HASHED and its length is:
// FileSize - (CertDirectory->Size)
//
if (ImageSize > SumOfBytesHashed) {
HashBase = (UINT8 *)(UINTN)ImageAddress + SumOfBytesHashed;
if (NumberOfRvaAndSizes <= EFI_IMAGE_DIRECTORY_ENTRY_SECURITY) {
CertSize = 0;
} else {
if (Hdr.Pe32->Magic == EFI_IMAGE_NT_OPTIONAL_HDR32_MAGIC) {
//
// Use PE32 offset.
//
CertSize = Hdr.Pe32->DataDirectory[EFI_IMAGE_DIRECTORY_ENTRY_SECURITY].Size;
} else {
//
// Use PE32+ offset.
//
CertSize = Hdr.Pe32Plus->DataDirectory[EFI_IMAGE_DIRECTORY_ENTRY_SECURITY].Size;
}
}
if (ImageSize > CertSize + SumOfBytesHashed) {
HashSize = (UINTN)(ImageSize - CertSize - SumOfBytesHashed);
Status = HashUpdate (HashHandle, HashBase, HashSize);
if (EFI_ERROR (Status)) {
goto Finish;
}
} else if (ImageSize < CertSize + SumOfBytesHashed) {
Status = EFI_UNSUPPORTED;
goto Finish;
}
}
//
// 17. Finalize the SHA hash.
//
Status = HashCompleteAndExtend (HashHandle, RtmrIndex, NULL, 0, DigestList);
if (EFI_ERROR (Status)) {
goto Finish;
}
Finish:
if (SectionHeader != NULL) {
FreePool (SectionHeader);
}
return Status;
}
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