src/boot/efi/measure.c - systemd-stable - Rivoreo Source Code Repositories

 /* SPDX-License-Identifier: LGPL-2.1+ */

 #if ENABLE_TPM

 #include <efi.h>
 #include <efilib.h>
 #include "measure.h"

 #define EFI_TCG_PROTOCOL_GUID { 0xf541796d, 0xa62e, 0x4954, {0xa7, 0x75, 0x95, 0x84, 0xf6, 0x1b, 0x9c, 0xdd} }

 typedef struct _TCG_VERSION {
         UINT8 Major;
         UINT8 Minor;
         UINT8 RevMajor;
         UINT8 RevMinor;
 } TCG_VERSION;

 typedef struct tdEFI_TCG2_VERSION {
         UINT8 Major;
         UINT8 Minor;
 } EFI_TCG2_VERSION;

 typedef struct _TCG_BOOT_SERVICE_CAPABILITY {
         UINT8 Size;
         struct _TCG_VERSION StructureVersion;
         struct _TCG_VERSION ProtocolSpecVersion;
         UINT8 HashAlgorithmBitmap;
         BOOLEAN TPMPresentFlag;
         BOOLEAN TPMDeactivatedFlag;
 } TCG_BOOT_SERVICE_CAPABILITY;

 typedef struct tdTREE_BOOT_SERVICE_CAPABILITY {
         UINT8 Size;
         EFI_TCG2_VERSION StructureVersion;
         EFI_TCG2_VERSION ProtocolVersion;
         UINT32 HashAlgorithmBitmap;
         UINT32 SupportedEventLogs;
         BOOLEAN TrEEPresentFlag;
         UINT16 MaxCommandSize;
         UINT16 MaxResponseSize;
         UINT32 ManufacturerID;
 } TREE_BOOT_SERVICE_CAPABILITY;

 typedef UINT32 TCG_ALGORITHM_ID;
 #define TCG_ALG_SHA 0x00000004  // The SHA1 algorithm

 #define SHA1_DIGEST_SIZE 20

 typedef struct _TCG_DIGEST {
         UINT8 Digest[SHA1_DIGEST_SIZE];
 } TCG_DIGEST;

 #define EV_IPL 13

 typedef struct _TCG_PCR_EVENT {
         UINT32 PCRIndex;
         UINT32 EventType;
         struct _TCG_DIGEST digest;
         UINT32 EventSize;
         UINT8 Event[1];
 } TCG_PCR_EVENT;

 INTERFACE_DECL(_EFI_TCG);

 typedef EFI_STATUS(EFIAPI * EFI_TCG_STATUS_CHECK) (IN struct _EFI_TCG * This,
                                                    OUT struct _TCG_BOOT_SERVICE_CAPABILITY * ProtocolCapability,
                                                    OUT UINT32 * TCGFeatureFlags,
                                                    OUT EFI_PHYSICAL_ADDRESS * EventLogLocation,
                                                    OUT EFI_PHYSICAL_ADDRESS * EventLogLastEntry);

 typedef EFI_STATUS(EFIAPI * EFI_TCG_HASH_ALL) (IN struct _EFI_TCG * This,
                                                IN UINT8 * HashData,
                                                IN UINT64 HashDataLen,
                                                IN TCG_ALGORITHM_ID AlgorithmId,
                                                IN OUT UINT64 * HashedDataLen, IN OUT UINT8 ** HashedDataResult);

 typedef EFI_STATUS(EFIAPI * EFI_TCG_LOG_EVENT) (IN struct _EFI_TCG * This,
                                                 IN struct _TCG_PCR_EVENT * TCGLogData,
                                                 IN OUT UINT32 * EventNumber, IN UINT32 Flags);

 typedef EFI_STATUS(EFIAPI * EFI_TCG_PASS_THROUGH_TO_TPM) (IN struct _EFI_TCG * This,
                                                           IN UINT32 TpmInputParameterBlockSize,
                                                           IN UINT8 * TpmInputParameterBlock,
                                                           IN UINT32 TpmOutputParameterBlockSize,
                                                           IN UINT8 * TpmOutputParameterBlock);

 typedef EFI_STATUS(EFIAPI * EFI_TCG_HASH_LOG_EXTEND_EVENT) (IN struct _EFI_TCG * This,
                                                             IN EFI_PHYSICAL_ADDRESS HashData,
                                                             IN UINT64 HashDataLen,
                                                             IN TCG_ALGORITHM_ID AlgorithmId,
                                                             IN struct _TCG_PCR_EVENT * TCGLogData,
                                                             IN OUT UINT32 * EventNumber,
                                                             OUT EFI_PHYSICAL_ADDRESS * EventLogLastEntry);

 typedef struct _EFI_TCG {
         EFI_TCG_STATUS_CHECK StatusCheck;
         EFI_TCG_HASH_ALL HashAll;
         EFI_TCG_LOG_EVENT LogEvent;
         EFI_TCG_PASS_THROUGH_TO_TPM PassThroughToTPM;
         EFI_TCG_HASH_LOG_EXTEND_EVENT HashLogExtendEvent;
 } EFI_TCG;

 #define EFI_TCG2_PROTOCOL_GUID {0x607f766c, 0x7455, 0x42be, { 0x93, 0x0b, 0xe4, 0xd7, 0x6d, 0xb2, 0x72, 0x0f }}

 typedef struct tdEFI_TCG2_PROTOCOL EFI_TCG2_PROTOCOL;

 typedef UINT32 EFI_TCG2_EVENT_LOG_BITMAP;
 typedef UINT32 EFI_TCG2_EVENT_LOG_FORMAT;
 typedef UINT32 EFI_TCG2_EVENT_ALGORITHM_BITMAP;

 typedef struct tdEFI_TCG2_BOOT_SERVICE_CAPABILITY {
         UINT8 Size;
         EFI_TCG2_VERSION StructureVersion;
         EFI_TCG2_VERSION ProtocolVersion;
         EFI_TCG2_EVENT_ALGORITHM_BITMAP HashAlgorithmBitmap;
         EFI_TCG2_EVENT_LOG_BITMAP SupportedEventLogs;
         BOOLEAN TPMPresentFlag;
         UINT16 MaxCommandSize;
         UINT16 MaxResponseSize;
         UINT32 ManufacturerID;
         UINT32 NumberOfPCRBanks;
         EFI_TCG2_EVENT_ALGORITHM_BITMAP ActivePcrBanks;
 } EFI_TCG2_BOOT_SERVICE_CAPABILITY;

 #define EFI_TCG2_EVENT_HEADER_VERSION  1

 typedef struct {
         UINT32 HeaderSize;
         UINT16 HeaderVersion;
         UINT32 PCRIndex;
         UINT32 EventType;
 } __attribute__((packed)) EFI_TCG2_EVENT_HEADER;

 typedef struct tdEFI_TCG2_EVENT {
         UINT32 Size;
         EFI_TCG2_EVENT_HEADER Header;
         UINT8 Event[1];
 } __attribute__((packed)) EFI_TCG2_EVENT;

 typedef EFI_STATUS(EFIAPI * EFI_TCG2_GET_CAPABILITY) (IN EFI_TCG2_PROTOCOL * This,
                                                       IN OUT EFI_TCG2_BOOT_SERVICE_CAPABILITY * ProtocolCapability);

 typedef EFI_STATUS(EFIAPI * EFI_TCG2_GET_EVENT_LOG) (IN EFI_TCG2_PROTOCOL * This,
                                                      IN EFI_TCG2_EVENT_LOG_FORMAT EventLogFormat,
                                                      OUT EFI_PHYSICAL_ADDRESS * EventLogLocation,
                                                      OUT EFI_PHYSICAL_ADDRESS * EventLogLastEntry,
                                                      OUT BOOLEAN * EventLogTruncated);

 typedef EFI_STATUS(EFIAPI * EFI_TCG2_HASH_LOG_EXTEND_EVENT) (IN EFI_TCG2_PROTOCOL * This,
                                                              IN UINT64 Flags,
                                                              IN EFI_PHYSICAL_ADDRESS DataToHash,
                                                              IN UINT64 DataToHashLen, IN EFI_TCG2_EVENT * EfiTcgEvent);

 typedef EFI_STATUS(EFIAPI * EFI_TCG2_SUBMIT_COMMAND) (IN EFI_TCG2_PROTOCOL * This,
                                                       IN UINT32 InputParameterBlockSize,
                                                       IN UINT8 * InputParameterBlock,
                                                       IN UINT32 OutputParameterBlockSize, IN UINT8 * OutputParameterBlock);

 typedef EFI_STATUS(EFIAPI * EFI_TCG2_GET_ACTIVE_PCR_BANKS) (IN EFI_TCG2_PROTOCOL * This, OUT UINT32 * ActivePcrBanks);

 typedef EFI_STATUS(EFIAPI * EFI_TCG2_SET_ACTIVE_PCR_BANKS) (IN EFI_TCG2_PROTOCOL * This, IN UINT32 ActivePcrBanks);

 typedef EFI_STATUS(EFIAPI * EFI_TCG2_GET_RESULT_OF_SET_ACTIVE_PCR_BANKS) (IN EFI_TCG2_PROTOCOL * This,
                                                                           OUT UINT32 * OperationPresent, OUT UINT32 * Response);

 typedef struct tdEFI_TCG2_PROTOCOL {
         EFI_TCG2_GET_CAPABILITY GetCapability;
         EFI_TCG2_GET_EVENT_LOG GetEventLog;
         EFI_TCG2_HASH_LOG_EXTEND_EVENT HashLogExtendEvent;
         EFI_TCG2_SUBMIT_COMMAND SubmitCommand;
         EFI_TCG2_GET_ACTIVE_PCR_BANKS GetActivePcrBanks;
         EFI_TCG2_SET_ACTIVE_PCR_BANKS SetActivePcrBanks;
         EFI_TCG2_GET_RESULT_OF_SET_ACTIVE_PCR_BANKS GetResultOfSetActivePcrBanks;
 } EFI_TCG2;

 static EFI_STATUS tpm1_measure_to_pcr_and_event_log(const EFI_TCG *tcg, UINT32 pcrindex, const EFI_PHYSICAL_ADDRESS buffer,
                                                     UINTN buffer_size, const CHAR16 *description) {
         EFI_STATUS status;
         TCG_PCR_EVENT *tcg_event;
         UINT32 event_number;
         EFI_PHYSICAL_ADDRESS event_log_last;
         UINTN desc_len;

         desc_len = (StrLen(description) + 1) * sizeof(CHAR16);

         tcg_event = AllocateZeroPool(desc_len + sizeof(TCG_PCR_EVENT));

         if (!tcg_event)
                 return EFI_OUT_OF_RESOURCES;

         tcg_event->EventSize = desc_len;
         CopyMem((VOID *) & tcg_event->Event[0], (VOID *) description, desc_len);

         tcg_event->PCRIndex = pcrindex;
         tcg_event->EventType = EV_IPL;

         event_number = 1;
         status = uefi_call_wrapper(tcg->HashLogExtendEvent, 7,
                                    (EFI_TCG *) tcg, buffer, buffer_size, TCG_ALG_SHA, tcg_event, &event_number, &event_log_last);

         if (EFI_ERROR(status))
                 return status;

         uefi_call_wrapper(BS->FreePool, 1, tcg_event);

         return EFI_SUCCESS;
 }

 static EFI_STATUS tpm2_measure_to_pcr_and_event_log(const EFI_TCG2 *tcg, UINT32 pcrindex, const EFI_PHYSICAL_ADDRESS buffer,
                                                     UINT64 buffer_size, const CHAR16 *description) {
         EFI_STATUS status;
         EFI_TCG2_EVENT *tcg_event;
         UINTN desc_len;

         desc_len = StrLen(description) * sizeof(CHAR16);

         tcg_event = AllocateZeroPool(sizeof(*tcg_event) - sizeof(tcg_event->Event) + desc_len + 1);

         if (!tcg_event)
                 return EFI_OUT_OF_RESOURCES;

         tcg_event->Size = sizeof(*tcg_event) - sizeof(tcg_event->Event) + desc_len + 1;
         tcg_event->Header.HeaderSize = sizeof(EFI_TCG2_EVENT_HEADER);
         tcg_event->Header.HeaderVersion = EFI_TCG2_EVENT_HEADER_VERSION;
         tcg_event->Header.PCRIndex = pcrindex;
         tcg_event->Header.EventType = EV_IPL;

         CopyMem((VOID *) tcg_event->Event, (VOID *) description, desc_len);

         status = uefi_call_wrapper(tcg->HashLogExtendEvent, 5, (EFI_TCG2 *) tcg, 0, buffer, (UINT64) buffer_size, tcg_event);

         uefi_call_wrapper(BS->FreePool, 1, tcg_event);

         if (EFI_ERROR(status))
                 return status;

         return EFI_SUCCESS;
 }

 static EFI_TCG * tcg1_interface_check(void) {
         EFI_GUID tpm_guid = EFI_TCG_PROTOCOL_GUID;
         EFI_STATUS status;
         EFI_TCG *tcg;
         TCG_BOOT_SERVICE_CAPABILITY capability;
         UINT32 features;
         EFI_PHYSICAL_ADDRESS event_log_location;
         EFI_PHYSICAL_ADDRESS event_log_last_entry;

         status = LibLocateProtocol(&tpm_guid, (void **) &tcg);

         if (EFI_ERROR(status))
                 return NULL;

         capability.Size = (UINT8) sizeof(capability);
         status = uefi_call_wrapper(tcg->StatusCheck, 5, tcg, &capability, &features, &event_log_location, &event_log_last_entry);

         if (EFI_ERROR(status))
                 return NULL;

         if (capability.TPMDeactivatedFlag)
                 return NULL;

         if (!capability.TPMPresentFlag)
                 return NULL;

         return tcg;
 }

 static EFI_TCG2 * tcg2_interface_check() {
         EFI_GUID tpm2_guid = EFI_TCG2_PROTOCOL_GUID;
         EFI_STATUS status;
         EFI_TCG2 *tcg;
         EFI_TCG2_BOOT_SERVICE_CAPABILITY capability;

         status = LibLocateProtocol(&tpm2_guid, (void **) &tcg);

         if (EFI_ERROR(status))
                 return NULL;

         capability.Size = (UINT8) sizeof(EFI_TCG2_BOOT_SERVICE_CAPABILITY);
         status = uefi_call_wrapper(tcg->GetCapability, 2, tcg, &capability);

         if (EFI_ERROR(status))
                 return NULL;

         if (capability.StructureVersion.Major == 1 &&
             capability.StructureVersion.Minor == 0) {
                 TCG_BOOT_SERVICE_CAPABILITY *caps_1_0;
                 caps_1_0 = (TCG_BOOT_SERVICE_CAPABILITY *)&capability;
                 if (caps_1_0->TPMPresentFlag)
                         return tcg;
         }

         if (!capability.TPMPresentFlag)
                 return NULL;

         return tcg;
 }

 EFI_STATUS tpm_log_event(UINT32 pcrindex, const EFI_PHYSICAL_ADDRESS buffer, UINTN buffer_size, const CHAR16 *description) {
         EFI_TCG *tpm1;
         EFI_TCG2 *tpm2;

         tpm2 = tcg2_interface_check();
         if (tpm2)
                 return tpm2_measure_to_pcr_and_event_log(tpm2, pcrindex, buffer, buffer_size, description);

         tpm1 = tcg1_interface_check();
         if (tpm1)
                 return tpm1_measure_to_pcr_and_event_log(tpm1, pcrindex, buffer, buffer_size, description);

         /* No active TPM found, so don't return an error */
         return EFI_SUCCESS;
 }

 #endif
	/* SPDX-License-Identifier: LGPL-2.1+ */

	#if ENABLE_TPM

	#include <efi.h>
	#include <efilib.h>
	#include "measure.h"

	#define EFI_TCG_PROTOCOL_GUID { 0xf541796d, 0xa62e, 0x4954, {0xa7, 0x75, 0x95, 0x84, 0xf6, 0x1b, 0x9c, 0xdd} }

	typedef struct _TCG_VERSION {
	UINT8 Major;
	UINT8 Minor;
	UINT8 RevMajor;
	UINT8 RevMinor;
	} TCG_VERSION;

	typedef struct tdEFI_TCG2_VERSION {
	UINT8 Major;
	UINT8 Minor;
	} EFI_TCG2_VERSION;

	typedef struct _TCG_BOOT_SERVICE_CAPABILITY {
	UINT8 Size;
	struct _TCG_VERSION StructureVersion;
	struct _TCG_VERSION ProtocolSpecVersion;
	UINT8 HashAlgorithmBitmap;
	BOOLEAN TPMPresentFlag;
	BOOLEAN TPMDeactivatedFlag;
	} TCG_BOOT_SERVICE_CAPABILITY;

	typedef struct tdTREE_BOOT_SERVICE_CAPABILITY {
	UINT8 Size;
	EFI_TCG2_VERSION StructureVersion;
	EFI_TCG2_VERSION ProtocolVersion;
	UINT32 HashAlgorithmBitmap;
	UINT32 SupportedEventLogs;
	BOOLEAN TrEEPresentFlag;
	UINT16 MaxCommandSize;
	UINT16 MaxResponseSize;
	UINT32 ManufacturerID;
	} TREE_BOOT_SERVICE_CAPABILITY;

	typedef UINT32 TCG_ALGORITHM_ID;
	#define TCG_ALG_SHA 0x00000004 // The SHA1 algorithm

	#define SHA1_DIGEST_SIZE 20

	typedef struct _TCG_DIGEST {
	UINT8 Digest[SHA1_DIGEST_SIZE];
	} TCG_DIGEST;

	#define EV_IPL 13

	typedef struct _TCG_PCR_EVENT {
	UINT32 PCRIndex;
	UINT32 EventType;
	struct _TCG_DIGEST digest;
	UINT32 EventSize;
	UINT8 Event[1];
	} TCG_PCR_EVENT;

	INTERFACE_DECL(_EFI_TCG);

	typedef EFI_STATUS(EFIAPI * EFI_TCG_STATUS_CHECK) (IN struct _EFI_TCG * This,
	OUT struct _TCG_BOOT_SERVICE_CAPABILITY * ProtocolCapability,
	OUT UINT32 * TCGFeatureFlags,
	OUT EFI_PHYSICAL_ADDRESS * EventLogLocation,
	OUT EFI_PHYSICAL_ADDRESS * EventLogLastEntry);

	typedef EFI_STATUS(EFIAPI * EFI_TCG_HASH_ALL) (IN struct _EFI_TCG * This,
	IN UINT8 * HashData,
	IN UINT64 HashDataLen,
	IN TCG_ALGORITHM_ID AlgorithmId,
	IN OUT UINT64 * HashedDataLen, IN OUT UINT8 ** HashedDataResult);

	typedef EFI_STATUS(EFIAPI * EFI_TCG_LOG_EVENT) (IN struct _EFI_TCG * This,
	IN struct _TCG_PCR_EVENT * TCGLogData,
	IN OUT UINT32 * EventNumber, IN UINT32 Flags);

	typedef EFI_STATUS(EFIAPI * EFI_TCG_PASS_THROUGH_TO_TPM) (IN struct _EFI_TCG * This,
	IN UINT32 TpmInputParameterBlockSize,
	IN UINT8 * TpmInputParameterBlock,
	IN UINT32 TpmOutputParameterBlockSize,
	IN UINT8 * TpmOutputParameterBlock);

	typedef EFI_STATUS(EFIAPI * EFI_TCG_HASH_LOG_EXTEND_EVENT) (IN struct _EFI_TCG * This,
	IN EFI_PHYSICAL_ADDRESS HashData,
	IN UINT64 HashDataLen,
	IN TCG_ALGORITHM_ID AlgorithmId,
	IN struct _TCG_PCR_EVENT * TCGLogData,
	IN OUT UINT32 * EventNumber,
	OUT EFI_PHYSICAL_ADDRESS * EventLogLastEntry);

	typedef struct _EFI_TCG {
	EFI_TCG_STATUS_CHECK StatusCheck;
	EFI_TCG_HASH_ALL HashAll;
	EFI_TCG_LOG_EVENT LogEvent;
	EFI_TCG_PASS_THROUGH_TO_TPM PassThroughToTPM;
	EFI_TCG_HASH_LOG_EXTEND_EVENT HashLogExtendEvent;
	} EFI_TCG;

	#define EFI_TCG2_PROTOCOL_GUID {0x607f766c, 0x7455, 0x42be, { 0x93, 0x0b, 0xe4, 0xd7, 0x6d, 0xb2, 0x72, 0x0f }}

	typedef struct tdEFI_TCG2_PROTOCOL EFI_TCG2_PROTOCOL;

	typedef UINT32 EFI_TCG2_EVENT_LOG_BITMAP;
	typedef UINT32 EFI_TCG2_EVENT_LOG_FORMAT;
	typedef UINT32 EFI_TCG2_EVENT_ALGORITHM_BITMAP;

	typedef struct tdEFI_TCG2_BOOT_SERVICE_CAPABILITY {
	UINT8 Size;
	EFI_TCG2_VERSION StructureVersion;
	EFI_TCG2_VERSION ProtocolVersion;
	EFI_TCG2_EVENT_ALGORITHM_BITMAP HashAlgorithmBitmap;
	EFI_TCG2_EVENT_LOG_BITMAP SupportedEventLogs;
	BOOLEAN TPMPresentFlag;
	UINT16 MaxCommandSize;
	UINT16 MaxResponseSize;
	UINT32 ManufacturerID;
	UINT32 NumberOfPCRBanks;
	EFI_TCG2_EVENT_ALGORITHM_BITMAP ActivePcrBanks;
	} EFI_TCG2_BOOT_SERVICE_CAPABILITY;

	#define EFI_TCG2_EVENT_HEADER_VERSION 1

	typedef struct {
	UINT32 HeaderSize;
	UINT16 HeaderVersion;
	UINT32 PCRIndex;
	UINT32 EventType;
	} __attribute__((packed)) EFI_TCG2_EVENT_HEADER;

	typedef struct tdEFI_TCG2_EVENT {
	UINT32 Size;
	EFI_TCG2_EVENT_HEADER Header;
	UINT8 Event[1];
	} __attribute__((packed)) EFI_TCG2_EVENT;

	typedef EFI_STATUS(EFIAPI * EFI_TCG2_GET_CAPABILITY) (IN EFI_TCG2_PROTOCOL * This,
	IN OUT EFI_TCG2_BOOT_SERVICE_CAPABILITY * ProtocolCapability);

	typedef EFI_STATUS(EFIAPI * EFI_TCG2_GET_EVENT_LOG) (IN EFI_TCG2_PROTOCOL * This,
	IN EFI_TCG2_EVENT_LOG_FORMAT EventLogFormat,
	OUT EFI_PHYSICAL_ADDRESS * EventLogLocation,
	OUT EFI_PHYSICAL_ADDRESS * EventLogLastEntry,
	OUT BOOLEAN * EventLogTruncated);

	typedef EFI_STATUS(EFIAPI * EFI_TCG2_HASH_LOG_EXTEND_EVENT) (IN EFI_TCG2_PROTOCOL * This,
	IN UINT64 Flags,
	IN EFI_PHYSICAL_ADDRESS DataToHash,
	IN UINT64 DataToHashLen, IN EFI_TCG2_EVENT * EfiTcgEvent);

	typedef EFI_STATUS(EFIAPI * EFI_TCG2_SUBMIT_COMMAND) (IN EFI_TCG2_PROTOCOL * This,
	IN UINT32 InputParameterBlockSize,
	IN UINT8 * InputParameterBlock,
	IN UINT32 OutputParameterBlockSize, IN UINT8 * OutputParameterBlock);

	typedef EFI_STATUS(EFIAPI * EFI_TCG2_GET_ACTIVE_PCR_BANKS) (IN EFI_TCG2_PROTOCOL * This, OUT UINT32 * ActivePcrBanks);

	typedef EFI_STATUS(EFIAPI * EFI_TCG2_SET_ACTIVE_PCR_BANKS) (IN EFI_TCG2_PROTOCOL * This, IN UINT32 ActivePcrBanks);

	typedef EFI_STATUS(EFIAPI * EFI_TCG2_GET_RESULT_OF_SET_ACTIVE_PCR_BANKS) (IN EFI_TCG2_PROTOCOL * This,
	OUT UINT32 * OperationPresent, OUT UINT32 * Response);

	typedef struct tdEFI_TCG2_PROTOCOL {
	EFI_TCG2_GET_CAPABILITY GetCapability;
	EFI_TCG2_GET_EVENT_LOG GetEventLog;
	EFI_TCG2_HASH_LOG_EXTEND_EVENT HashLogExtendEvent;
	EFI_TCG2_SUBMIT_COMMAND SubmitCommand;
	EFI_TCG2_GET_ACTIVE_PCR_BANKS GetActivePcrBanks;
	EFI_TCG2_SET_ACTIVE_PCR_BANKS SetActivePcrBanks;
	EFI_TCG2_GET_RESULT_OF_SET_ACTIVE_PCR_BANKS GetResultOfSetActivePcrBanks;
	} EFI_TCG2;

	static EFI_STATUS tpm1_measure_to_pcr_and_event_log(const EFI_TCG *tcg, UINT32 pcrindex, const EFI_PHYSICAL_ADDRESS buffer,
	UINTN buffer_size, const CHAR16 *description) {
	EFI_STATUS status;
	TCG_PCR_EVENT *tcg_event;
	UINT32 event_number;
	EFI_PHYSICAL_ADDRESS event_log_last;
	UINTN desc_len;

	desc_len = (StrLen(description) + 1) * sizeof(CHAR16);

	tcg_event = AllocateZeroPool(desc_len + sizeof(TCG_PCR_EVENT));

	if (!tcg_event)
	return EFI_OUT_OF_RESOURCES;

	tcg_event->EventSize = desc_len;
	CopyMem((VOID ) & tcg_event->Event[0], (VOID ) description, desc_len);

	tcg_event->PCRIndex = pcrindex;
	tcg_event->EventType = EV_IPL;

	event_number = 1;
	status = uefi_call_wrapper(tcg->HashLogExtendEvent, 7,
	(EFI_TCG *) tcg, buffer, buffer_size, TCG_ALG_SHA, tcg_event, &event_number, &event_log_last);

	if (EFI_ERROR(status))
	return status;

	uefi_call_wrapper(BS->FreePool, 1, tcg_event);

	return EFI_SUCCESS;
	}

	static EFI_STATUS tpm2_measure_to_pcr_and_event_log(const EFI_TCG2 *tcg, UINT32 pcrindex, const EFI_PHYSICAL_ADDRESS buffer,
	UINT64 buffer_size, const CHAR16 *description) {
	EFI_STATUS status;
	EFI_TCG2_EVENT *tcg_event;
	UINTN desc_len;

	desc_len = StrLen(description) * sizeof(CHAR16);

	tcg_event = AllocateZeroPool(sizeof(*tcg_event) - sizeof(tcg_event->Event) + desc_len + 1);

	if (!tcg_event)
	return EFI_OUT_OF_RESOURCES;

	tcg_event->Size = sizeof(*tcg_event) - sizeof(tcg_event->Event) + desc_len + 1;
	tcg_event->Header.HeaderSize = sizeof(EFI_TCG2_EVENT_HEADER);
	tcg_event->Header.HeaderVersion = EFI_TCG2_EVENT_HEADER_VERSION;
	tcg_event->Header.PCRIndex = pcrindex;
	tcg_event->Header.EventType = EV_IPL;

	CopyMem((VOID ) tcg_event->Event, (VOID ) description, desc_len);

	status = uefi_call_wrapper(tcg->HashLogExtendEvent, 5, (EFI_TCG2 *) tcg, 0, buffer, (UINT64) buffer_size, tcg_event);

	uefi_call_wrapper(BS->FreePool, 1, tcg_event);

	if (EFI_ERROR(status))
	return status;

	return EFI_SUCCESS;
	}

	static EFI_TCG * tcg1_interface_check(void) {
	EFI_GUID tpm_guid = EFI_TCG_PROTOCOL_GUID;
	EFI_STATUS status;
	EFI_TCG *tcg;
	TCG_BOOT_SERVICE_CAPABILITY capability;
	UINT32 features;
	EFI_PHYSICAL_ADDRESS event_log_location;
	EFI_PHYSICAL_ADDRESS event_log_last_entry;

	status = LibLocateProtocol(&tpm_guid, (void **) &tcg);

	if (EFI_ERROR(status))
	return NULL;

	capability.Size = (UINT8) sizeof(capability);
	status = uefi_call_wrapper(tcg->StatusCheck, 5, tcg, &capability, &features, &event_log_location, &event_log_last_entry);

	if (EFI_ERROR(status))
	return NULL;

	if (capability.TPMDeactivatedFlag)
	return NULL;

	if (!capability.TPMPresentFlag)
	return NULL;

	return tcg;
	}

	static EFI_TCG2 * tcg2_interface_check() {
	EFI_GUID tpm2_guid = EFI_TCG2_PROTOCOL_GUID;
	EFI_STATUS status;
	EFI_TCG2 *tcg;
	EFI_TCG2_BOOT_SERVICE_CAPABILITY capability;

	status = LibLocateProtocol(&tpm2_guid, (void **) &tcg);

	if (EFI_ERROR(status))
	return NULL;

	capability.Size = (UINT8) sizeof(EFI_TCG2_BOOT_SERVICE_CAPABILITY);
	status = uefi_call_wrapper(tcg->GetCapability, 2, tcg, &capability);

	if (EFI_ERROR(status))
	return NULL;

	if (capability.StructureVersion.Major == 1 &&
	capability.StructureVersion.Minor == 0) {
	TCG_BOOT_SERVICE_CAPABILITY *caps_1_0;
	caps_1_0 = (TCG_BOOT_SERVICE_CAPABILITY *)&capability;
	if (caps_1_0->TPMPresentFlag)
	return tcg;
	}

	if (!capability.TPMPresentFlag)
	return NULL;

	return tcg;
	}

	EFI_STATUS tpm_log_event(UINT32 pcrindex, const EFI_PHYSICAL_ADDRESS buffer, UINTN buffer_size, const CHAR16 *description) {
	EFI_TCG *tpm1;
	EFI_TCG2 *tpm2;

	tpm2 = tcg2_interface_check();
	if (tpm2)
	return tpm2_measure_to_pcr_and_event_log(tpm2, pcrindex, buffer, buffer_size, description);

	tpm1 = tcg1_interface_check();
	if (tpm1)
	return tpm1_measure_to_pcr_and_event_log(tpm1, pcrindex, buffer, buffer_size, description);

	/* No active TPM found, so don't return an error */
	return EFI_SUCCESS;
	}

	#endif