/**
Hash data and extend to PCR.
@param PcrIndex PCR to be extended.
@param DataToHash Data to be hashed.
@param DataToHashLen Data size.
@param DigestList Digest list.
@retval EFI_SUCCESS Hash data and DigestList is returned.
**/
EFI_STATUS
EFIAPI
HashAndExtend (
IN TPMI_DH_PCR PcrIndex,
IN VOID *DataToHash,
IN UINTN DataToHashLen,
OUT TPML_DIGEST_VALUES *DigestList
)
{
HASH_INTERFACE_HOB *HashInterfaceHob;
HASH_HANDLE HashHandle;
EFI_STATUS Status;
HashInterfaceHob = InternalGetHashInterface ();
if (HashInterfaceHob == NULL) {
return EFI_UNSUPPORTED;
}
if (HashInterfaceHob->HashInterfaceCount == 0) {
return EFI_UNSUPPORTED;
}
HashStart (&HashHandle);
HashUpdate (HashHandle, DataToHash, DataToHashLen);
Status = HashCompleteAndExtend (HashHandle, PcrIndex, NULL, 0, DigestList);
return Status;
}
/**Send a slave error packet
* @param error The error code. Error codes are defined in the header file.
* @param description Pointer to a null-terminated string of additional data about the error
*/
void SendSlaveError(unsigned char error, char *description)
{
HashState=0;
//Send the preamble
BufferedSerialWrite(0x55);
BufferedSerialWrite(TYPE_SLAVE_EXCEPTION);
HashUpdate(TYPE_SLAVE_EXCEPTION);
//Adress to master
BufferedSerialWrite(1);
HashUpdate(1);
BufferedSerialWrite(0);
HashUpdate(0);
BufferedSerialWrite(PACKET_OVERHEAD + 1);
HashUpdate(PACKET_OVERHEAD+1);
BufferedSerialWrite(error);
HashUpdate(error);
BufferedSerialWrite(GetByteOf(1,HashState));
BufferedSerialWrite(GetByteOf(0,HashState));
//
}
/**Print a null terminated string to the serial port
* Hash every character, but do not reset the hash state beforehand.
* @param str A null terminated string to be sent.
*/
void PrintNstringAndHash(const unsigned char *str)
{
unsigned char temp = 00;
//This is just a counter to make sure we dont loop forever if no NUL is found
unsigned char SafetyCounter =00;
while(SafetyCounter<240)
{
temp = *str++;
if (temp)
{
HashUpdate(temp);
BufferedSerialWrite(temp) ;
}
else
{
HashUpdate(0);
BufferedSerialWrite(0) ;
break;
}
SafetyCounter++;
}
}
/**Send a slave data response packet. You only need to give it the data, it will handle framing.
* @param data A pointer to the start of the data to be sent
* @data_length The length of the data to be sent
*/
void SendSlaveDataResponse(const unsigned char *data, const unsigned char data_length)
{
//Initialize the CRC state
HashState = 0;
//We hash every byte we send but NOT the preamble because it is
//not part of the packet data.
//preamble
BufferedSerialWrite(PACKET_PREAMBLE);
//Send the packet type code,
BufferedSerialWrite(TYPE_SLAVE_DATA_RESPONSE);
HashUpdate(TYPE_SLAVE_DATA_RESPONSE);
BufferedSerialWrite(0x01);
HashUpdate(0x01);
BufferedSerialWrite(0x00);
HashUpdate(0x00);
//Calculate what the length field will be because
//The length field is not the same as the length of the actual data.
BufferedSerialWrite(data_length +PACKET_OVERHEAD);
HashUpdate(data_length+PACKET_OVERHEAD);
//Send each character of the actual data and hash it
unsigned char i;
for(i=0; i<data_length; i++)
{
BufferedSerialWrite(data[i]);
HashUpdate(data[i]);
}
BufferedSerialWrite(GetByteOf(1,HashState));
BufferedSerialWrite(GetByteOf(0,HashState));
}
/**This should get called every time a new byte is availible from the UART.
* @param byte the new byte that just arrived.
*/
void OnByteRecieved(const unsigned char byte)
{
//Check the interframe spacing.
//If it has been more than that time it is either an error or a new packet.
//also check if we arent recieving a message at all.
//Either of these conditions indicate that this byte could be the start of a new character.
if (((TimeSinceLastByteWasRecieved() >= CurrentTimeOut)) | !(RecievingMessage))
{
//A byte time of silence or more always delimits packets
//So reset the recieve pointer to clear any garbage and reset the hash state.
RecievePointer = 0;
HashState = 0;
//Consider this the start of a new packet ONLY if it matches the valid start code
//And ONLY if the required interframe distance has been met or exceeded.
//This lets us send one byte messages outside of a full packet
if (byte == 0x55)
{
RecievingMessage = 1;
}
else
{
//If we don't see the valid start code we stay idle
RecievingMessage = 0;
}
return;
}
//Only if a valid start code was detected at the start should we enter the byte in the buffer.
else
{
RecieveBuffer[RecievePointer] = byte;
RecievePointer++;
//Update the checksum as we go so we don't have to do one huge batch of calculations
//At the end, which would suck for realtime performance.
//Also dont CRC the CRC because that would
//not make sense unless we did that weird crc(message +crc)=0 thing
if (!((RecievePointer >= (RecieveBuffer[LENGTH_OFFSET]-1)) &(RecievePointer>LENGTH_OFFSET)))
{
HashUpdate(byte);
}
//Not only check and see if we have as mny bytes as the length field says,
//But also check that we even have the length field.
if ((RecievePointer >= RecieveBuffer[LENGTH_OFFSET]) &(RecievePointer>LENGTH_OFFSET))
{
//If we have recieved a complete message, Check the checksum.
// DisableReciever(); //We must re enable this to be ready for the next packet.
RecievingMessage = 0;
//Do nothing with the packet if we have just been waiting for the end of it.
if (CheckAddress(RecieveBuffer))
{
//Don't do anything with incorrect packets, they are bad.
if (GetByteOf(0,HashState ) == RecieveBuffer[RecievePointer-1])
{
if(GetByteOf(1,HashState) == RecieveBuffer[RecievePointer-2])
{
HandleNewPacket(RecieveBuffer);
}
}
}
}
}
}
/**
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] PCRIndex TPM PCR index
@param[in] ImageAddress Start address of image buffer.
@param[in] ImageSize Image size
@param[out] DigestList Digeest 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 PCRIndex,
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;
UINT16 Magic;
EFI_IMAGE_OPTIONAL_HEADER_PTR_UNION Hdr;
UINT32 NumberOfRvaAndSizes;
UINT32 CertSize;
HASH_HANDLE HashHandle;
HashHandle = 0xFFFFFFFF; // Know bad value
Status = EFI_UNSUPPORTED;
SectionHeader = NULL;
//
// 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) {
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
//
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);
}
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 (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) {
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 (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) {
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 (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) {
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 (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;
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 (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);
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, PCRIndex, NULL, 0, DigestList);
if (EFI_ERROR (Status)) {
goto Finish;
}
Finish:
if (SectionHeader != NULL) {
FreePool (SectionHeader);
}
return Status;
}
