/**
Single function calculates SHA1 digest value for all raw data. It
combines Sha1Init(), Sha1Update() and Sha1Final().
@param[in] Data Raw data to be digested.
@param[in] DataLen Size of the raw data.
@param[out] Digest Pointer to a buffer that stores the final digest.
@retval EFI_SUCCESS Always successfully calculate the final digest.
**/
EFI_STATUS
EFIAPI
TpmCommHashAll (
IN CONST UINT8 *Data,
IN UINTN DataLen,
OUT TPM_DIGEST *Digest
)
{
VOID *Sha1Ctx;
UINTN CtxSize;
CtxSize = Sha1GetContextSize ();
Sha1Ctx = AllocatePool (CtxSize);
ASSERT (Sha1Ctx != NULL);
Sha1Init (Sha1Ctx);
Sha1Update (Sha1Ctx, Data, DataLen);
Sha1Final (Sha1Ctx, (UINT8 *)Digest);
FreePool (Sha1Ctx);
return EFI_SUCCESS;
}
/**
Calculates the hash of the given data based on the specified hash GUID.
@param[in] Data Pointer to the data buffer to be hashed.
@param[in] DataSize The size of data buffer in bytes.
@param[in] CertGuid The GUID to identify the hash algorithm to be used.
@param[out] HashValue Pointer to a buffer that receives the hash result.
@retval TRUE Data hash calculation succeeded.
@retval FALSE Data hash calculation failed.
**/
BOOLEAN
CalculateDataHash (
IN VOID *Data,
IN UINTN DataSize,
IN EFI_GUID *CertGuid,
OUT UINT8 *HashValue
)
{
BOOLEAN Status;
VOID *HashCtx;
UINTN CtxSize;
Status = FALSE;
HashCtx = NULL;
if (CompareGuid (CertGuid, &gEfiCertSha1Guid)) {
//
// SHA-1 Hash
//
CtxSize = Sha1GetContextSize ();
HashCtx = AllocatePool (CtxSize);
if (HashCtx == NULL) {
goto _Exit;
}
Status = Sha1Init (HashCtx);
Status = Sha1Update (HashCtx, Data, DataSize);
Status = Sha1Final (HashCtx, HashValue);
} else if (CompareGuid (CertGuid, &gEfiCertSha256Guid)) {
//
// SHA256 Hash
//
CtxSize = Sha256GetContextSize ();
HashCtx = AllocatePool (CtxSize);
if (HashCtx == NULL) {
goto _Exit;
}
Status = Sha256Init (HashCtx);
Status = Sha256Update (HashCtx, Data, DataSize);
Status = Sha256Final (HashCtx, HashValue);
} else if (CompareGuid (CertGuid, &gEfiCertSha384Guid)) {
//
// SHA384 Hash
//
CtxSize = Sha384GetContextSize ();
HashCtx = AllocatePool (CtxSize);
if (HashCtx == NULL) {
goto _Exit;
}
Status = Sha384Init (HashCtx);
Status = Sha384Update (HashCtx, Data, DataSize);
Status = Sha384Final (HashCtx, HashValue);
} else if (CompareGuid (CertGuid, &gEfiCertSha512Guid)) {
//
// SHA512 Hash
//
CtxSize = Sha512GetContextSize ();
HashCtx = AllocatePool (CtxSize);
if (HashCtx == NULL) {
goto _Exit;
}
Status = Sha512Init (HashCtx);
Status = Sha512Update (HashCtx, Data, DataSize);
Status = Sha512Final (HashCtx, HashValue);
}
_Exit:
if (HashCtx != NULL) {
FreePool (HashCtx);
}
return Status;
}
/**
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.
@param[in] TcgProtocol Pointer to the located TCG protocol instance.
@param[in] ImageAddress Start address of image buffer.
@param[in] ImageSize Image size
@param[in] LinkTimeBase Address that the image is loaded into memory.
@param[in] ImageType Image subsystem type.
@param[in] FilePath File path is corresponding to the input image.
@retval EFI_SUCCESS Successfully measure image.
@retval EFI_OUT_OF_RESOURCES No enough resource to measure image.
@retval EFI_UNSUPPORTED ImageType is unsupported or PE image is mal-format.
@retval other error value
**/
EFI_STATUS
EFIAPI
TcgMeasurePeImage (
IN EFI_TCG_PROTOCOL *TcgProtocol,
IN EFI_PHYSICAL_ADDRESS ImageAddress,
IN UINTN ImageSize,
IN UINTN LinkTimeBase,
IN UINT16 ImageType,
IN EFI_DEVICE_PATH_PROTOCOL *FilePath
)
{
EFI_STATUS Status;
TCG_PCR_EVENT *TcgEvent;
EFI_IMAGE_LOAD_EVENT *ImageLoad;
UINT32 FilePathSize;
VOID *Sha1Ctx;
UINTN CtxSize;
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;
UINT16 Magic;
UINT32 EventSize;
UINT32 EventNumber;
EFI_PHYSICAL_ADDRESS EventLogLastEntry;
EFI_IMAGE_OPTIONAL_HEADER_PTR_UNION Hdr;
UINT32 NumberOfRvaAndSizes;
BOOLEAN HashStatus;
UINT32 CertSize;
Status = EFI_UNSUPPORTED;
ImageLoad = NULL;
SectionHeader = NULL;
Sha1Ctx = NULL;
FilePathSize = (UINT32) GetDevicePathSize (FilePath);
//
// Determine destination PCR by BootPolicy
//
EventSize = sizeof (*ImageLoad) - sizeof (ImageLoad->DevicePath) + FilePathSize;
TcgEvent = AllocateZeroPool (EventSize + sizeof (TCG_PCR_EVENT));
if (TcgEvent == NULL) {
return EFI_OUT_OF_RESOURCES;
}
TcgEvent->EventSize = EventSize;
ImageLoad = (EFI_IMAGE_LOAD_EVENT *) TcgEvent->Event;
switch (ImageType) {
case EFI_IMAGE_SUBSYSTEM_EFI_APPLICATION:
TcgEvent->EventType = EV_EFI_BOOT_SERVICES_APPLICATION;
TcgEvent->PCRIndex = 4;
break;
case EFI_IMAGE_SUBSYSTEM_EFI_BOOT_SERVICE_DRIVER:
TcgEvent->EventType = EV_EFI_BOOT_SERVICES_DRIVER;
TcgEvent->PCRIndex = 2;
break;
case EFI_IMAGE_SUBSYSTEM_EFI_RUNTIME_DRIVER:
TcgEvent->EventType = EV_EFI_RUNTIME_SERVICES_DRIVER;
TcgEvent->PCRIndex = 2;
break;
default:
DEBUG ((
EFI_D_ERROR,
"TcgMeasurePeImage: Unknown subsystem type %d",
ImageType
));
goto Finish;
}
ImageLoad->ImageLocationInMemory = ImageAddress;
ImageLoad->ImageLengthInMemory = ImageSize;
ImageLoad->ImageLinkTimeAddress = LinkTimeBase;
ImageLoad->LengthOfDevicePath = FilePathSize;
if ((FilePath != NULL) && (FilePathSize != 0)) {
CopyMem (ImageLoad->DevicePath, FilePath, FilePathSize);
}
//
// Check PE/COFF image
//
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->Signature != EFI_IMAGE_NT_SIGNATURE) {
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.
CtxSize = Sha1GetContextSize ();
Sha1Ctx = AllocatePool (CtxSize);
if (Sha1Ctx == NULL) {
Status = EFI_OUT_OF_RESOURCES;
goto Finish;
}
HashStatus = Sha1Init (Sha1Ctx);
if (!HashStatus) {
goto Finish;
}
//
// Measuring PE/COFF Image Header;
// But CheckSum field and SECURITY data directory (certificate) are excluded
//
if (Hdr.Pe32->FileHeader.Machine == IMAGE_FILE_MACHINE_IA64 && Hdr.Pe32->OptionalHeader.Magic == EFI_IMAGE_NT_OPTIONAL_HDR32_MAGIC) {
//
// NOTE: Some versions of Linux ELILO for Itanium have an incorrect magic value
// in the PE/COFF Header. If the MachineType is Itanium(IA64) and the
// Magic value in the OptionalHeader is EFI_IMAGE_NT_OPTIONAL_HDR32_MAGIC
// then override the magic value to EFI_IMAGE_NT_OPTIONAL_HDR64_MAGIC
//
Magic = EFI_IMAGE_NT_OPTIONAL_HDR64_MAGIC;
} else {
//
// Get the magic value from the PE/COFF Optional Header
//
Magic = Hdr.Pe32->OptionalHeader.Magic;
}
//
// 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 (Magic == EFI_IMAGE_NT_OPTIONAL_HDR32_MAGIC) {
//
// Use PE32 offset
//
NumberOfRvaAndSizes = Hdr.Pe32->OptionalHeader.NumberOfRvaAndSizes;
HashSize = (UINTN) ((UINT8 *)(&Hdr.Pe32->OptionalHeader.CheckSum) - HashBase);
} else {
//
// Use PE32+ offset
//
NumberOfRvaAndSizes = Hdr.Pe32Plus->OptionalHeader.NumberOfRvaAndSizes;
HashSize = (UINTN) ((UINT8 *)(&Hdr.Pe32Plus->OptionalHeader.CheckSum) - HashBase);
}
HashStatus = Sha1Update (Sha1Ctx, HashBase, HashSize);
if (!HashStatus) {
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 (Magic == EFI_IMAGE_NT_OPTIONAL_HDR32_MAGIC) {
//
// Use PE32 offset.
//
HashBase = (UINT8 *) &Hdr.Pe32->OptionalHeader.CheckSum + sizeof (UINT32);
HashSize = Hdr.Pe32->OptionalHeader.SizeOfHeaders - (UINTN) (HashBase - ImageAddress);
} else {
//
// Use PE32+ offset.
//
HashBase = (UINT8 *) &Hdr.Pe32Plus->OptionalHeader.CheckSum + sizeof (UINT32);
HashSize = Hdr.Pe32Plus->OptionalHeader.SizeOfHeaders - (UINTN) (HashBase - ImageAddress);
}
if (HashSize != 0) {
HashStatus = Sha1Update (Sha1Ctx, HashBase, HashSize);
if (!HashStatus) {
goto Finish;
}
}
} else {
//
// 7. Hash everything from the end of the checksum to the start of the Cert Directory.
//
if (Magic == EFI_IMAGE_NT_OPTIONAL_HDR32_MAGIC) {
//
// Use PE32 offset
//
HashBase = (UINT8 *) &Hdr.Pe32->OptionalHeader.CheckSum + sizeof (UINT32);
HashSize = (UINTN) ((UINT8 *)(&Hdr.Pe32->OptionalHeader.DataDirectory[EFI_IMAGE_DIRECTORY_ENTRY_SECURITY]) - HashBase);
} else {
//
// Use PE32+ offset
//
HashBase = (UINT8 *) &Hdr.Pe32Plus->OptionalHeader.CheckSum + sizeof (UINT32);
HashSize = (UINTN) ((UINT8 *)(&Hdr.Pe32Plus->OptionalHeader.DataDirectory[EFI_IMAGE_DIRECTORY_ENTRY_SECURITY]) - HashBase);
}
if (HashSize != 0) {
HashStatus = Sha1Update (Sha1Ctx, HashBase, HashSize);
if (!HashStatus) {
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 (Magic == EFI_IMAGE_NT_OPTIONAL_HDR32_MAGIC) {
//
// Use PE32 offset
//
HashBase = (UINT8 *) &Hdr.Pe32->OptionalHeader.DataDirectory[EFI_IMAGE_DIRECTORY_ENTRY_SECURITY + 1];
HashSize = Hdr.Pe32->OptionalHeader.SizeOfHeaders - (UINTN) (HashBase - ImageAddress);
} else {
//
// Use PE32+ offset
//
HashBase = (UINT8 *) &Hdr.Pe32Plus->OptionalHeader.DataDirectory[EFI_IMAGE_DIRECTORY_ENTRY_SECURITY + 1];
HashSize = Hdr.Pe32Plus->OptionalHeader.SizeOfHeaders - (UINTN) (HashBase - ImageAddress);
}
if (HashSize != 0) {
HashStatus = Sha1Update (Sha1Ctx, HashBase, HashSize);
if (!HashStatus) {
goto Finish;
}
}
}
//
// 10. Set the SUM_OF_BYTES_HASHED to the size of the header
//
if (Magic == EFI_IMAGE_NT_OPTIONAL_HDR32_MAGIC) {
//
// Use PE32 offset
//
SumOfBytesHashed = Hdr.Pe32->OptionalHeader.SizeOfHeaders;
} else {
//
// Use PE32+ offset
//
SumOfBytesHashed = Hdr.Pe32Plus->OptionalHeader.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->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->FileHeader.SizeOfOptionalHeader
);
for (Index = 0; Index < Hdr.Pe32->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->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;
HashStatus = Sha1Update (Sha1Ctx, HashBase, HashSize);
if (!HashStatus) {
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 (Magic == EFI_IMAGE_NT_OPTIONAL_HDR32_MAGIC) {
//
// Use PE32 offset.
//
CertSize = Hdr.Pe32->OptionalHeader.DataDirectory[EFI_IMAGE_DIRECTORY_ENTRY_SECURITY].Size;
} else {
//
// Use PE32+ offset.
//
CertSize = Hdr.Pe32Plus->OptionalHeader.DataDirectory[EFI_IMAGE_DIRECTORY_ENTRY_SECURITY].Size;
}
}
if (ImageSize > CertSize + SumOfBytesHashed) {
HashSize = (UINTN) (ImageSize - CertSize - SumOfBytesHashed);
HashStatus = Sha1Update (Sha1Ctx, HashBase, HashSize);
if (!HashStatus) {
goto Finish;
}
} else if (ImageSize < CertSize + SumOfBytesHashed) {
goto Finish;
}
}
//
// 17. Finalize the SHA hash.
//
HashStatus = Sha1Final (Sha1Ctx, (UINT8 *) &TcgEvent->Digest);
if (!HashStatus) {
goto Finish;
}
//
// Log the PE data
//
EventNumber = 1;
Status = TcgProtocol->HashLogExtendEvent (
TcgProtocol,
(EFI_PHYSICAL_ADDRESS) (UINTN) (VOID *) NULL,
0,
TPM_ALG_SHA,
TcgEvent,
&EventNumber,
&EventLogLastEntry
);
if (Status == EFI_OUT_OF_RESOURCES) {
//
// Out of resource here means the image is hashed and its result is extended to PCR.
// But the event log cann't be saved since log area is full.
// Just return EFI_SUCCESS in order not to block the image load.
//
Status = EFI_SUCCESS;
}
Finish:
FreePool (TcgEvent);
if (SectionHeader != NULL) {
FreePool (SectionHeader);
}
if (Sha1Ctx != NULL ) {
FreePool (Sha1Ctx);
}
return Status;
}
