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Commit 58cc1e4f authored by Thiebaud Weksteen's avatar Thiebaud Weksteen Committed by Jarkko Sakkinen
Browse files

tpm: parse TPM event logs based on EFI table 



If we are not able to retrieve the TPM event logs from the ACPI table,
check the EFI configuration table (Linux-specific GUID).

The format version of the log is now returned by the provider function.

Signed-off-by: default avatarThiebaud Weksteen <tweek@google.com>
Reviewed-by: default avatarJason Gunthorpe <jgunthorpe@obsidianresearch.com>
Reviewed-by: default avatarJavier Martinez Canillas <javierm@redhat.com>
Tested-by: default avatarJavier Martinez Canillas <javierm@redhat.com>
Tested-by: default avatarJarkko Sakkinen <jarkko.sakkinen@linux.intel.com>
Reviewed-by: default avatarJarkko Sakkinen <jarkko.sakkinen@linux.intel.com>
Signed-off-by: default avatarJarkko Sakkinen <jarkko.sakkinen@linux.intel.com>
parent 33b6d034

drivers/char/tpm/Makefile

+1 −0
Original line number Diff line number Diff line
@@ -7,6 +7,7 @@ tpm-y := tpm-interface.o tpm-dev.o tpm-sysfs.o tpm-chip.o tpm2-cmd.o \ 
	 tpm-dev-common.o tpmrm-dev.o tpm1_eventlog.o tpm2_eventlog.o \

         tpm2-space.o

tpm-$(CONFIG_ACPI) += tpm_ppi.o tpm_eventlog_acpi.o

tpm-$(CONFIG_EFI) += tpm_eventlog_efi.o

tpm-$(CONFIG_OF) += tpm_eventlog_of.o

obj-$(CONFIG_TCG_TIS_CORE) += tpm_tis_core.o

obj-$(CONFIG_TCG_TIS) += tpm_tis.o

drivers/char/tpm/tpm.h

+8 −0
Original line number Diff line number Diff line
@@ -589,6 +589,14 @@ static inline int tpm_read_log_of(struct tpm_chip *chip) 
	return -ENODEV;

}

#endif

#if defined(CONFIG_EFI)

int tpm_read_log_efi(struct tpm_chip *chip);

#else

static inline int tpm_read_log_efi(struct tpm_chip *chip)

{

	return -ENODEV;

}

#endif



int tpm_bios_log_setup(struct tpm_chip *chip);

void tpm_bios_log_teardown(struct tpm_chip *chip);

drivers/char/tpm/tpm1_eventlog.c

+9 −2
Original line number Diff line number Diff line
@@ -21,6 +21,7 @@ 
 */



#include <linux/seq_file.h>

#include <linux/efi.h>

#include <linux/fs.h>

#include <linux/security.h>

#include <linux/module.h>
@@ -371,6 +372,10 @@ static int tpm_read_log(struct tpm_chip *chip) 
	if (rc != -ENODEV)

		return rc;



	rc = tpm_read_log_efi(chip);

	if (rc != -ENODEV)

		return rc;



	return tpm_read_log_of(chip);

}
@@ -388,11 +393,13 @@ int tpm_bios_log_setup(struct tpm_chip *chip) 
{

	const char *name = dev_name(&chip->dev);

	unsigned int cnt;

	int log_version;

	int rc = 0;



	rc = tpm_read_log(chip);

	if (rc)

	if (rc < 0)

		return rc;

	log_version = rc;



	cnt = 0;

	chip->bios_dir[cnt] = securityfs_create_dir(name, NULL);
@@ -404,7 +411,7 @@ int tpm_bios_log_setup(struct tpm_chip *chip) 
	cnt++;



	chip->bin_log_seqops.chip = chip;

	if (chip->flags & TPM_CHIP_FLAG_TPM2)

	if (log_version == EFI_TCG2_EVENT_LOG_FORMAT_TCG_2)

		chip->bin_log_seqops.seqops =

			&tpm2_binary_b_measurements_seqops;

	else

drivers/char/tpm/tpm_eventlog_acpi.c

+1 −1
Original line number Diff line number Diff line
@@ -102,7 +102,7 @@ int tpm_read_log_acpi(struct tpm_chip *chip) 
	memcpy_fromio(log->bios_event_log, virt, len);



	acpi_os_unmap_iomem(virt, len);

	return 0;

	return EFI_TCG2_EVENT_LOG_FORMAT_TCG_1_2;



err:

	kfree(log->bios_event_log);

drivers/char/tpm/tpm_eventlog_efi.c

0 → 100644
+66 −0
Original line number Diff line number Diff line 
/*

 * Copyright (C) 2017 Google

 *

 * Authors:

 *      Thiebaud Weksteen <tweek@google.com>

 *

 * This program is free software; you can redistribute it and/or

 * modify it under the terms of the GNU General Public License

 * as published by the Free Software Foundation; either version

 * 2 of the License, or (at your option) any later version.

 *

 */



#include <linux/efi.h>

#include <linux/tpm_eventlog.h>



#include "tpm.h"



/* read binary bios log from EFI configuration table */

int tpm_read_log_efi(struct tpm_chip *chip)

{



	struct linux_efi_tpm_eventlog *log_tbl;

	struct tpm_bios_log *log;

	u32 log_size;

	u8 tpm_log_version;



	if (!(chip->flags & TPM_CHIP_FLAG_TPM2))

		return -ENODEV;



	if (efi.tpm_log == EFI_INVALID_TABLE_ADDR)

		return -ENODEV;



	log = &chip->log;



	log_tbl = memremap(efi.tpm_log, sizeof(*log_tbl), MEMREMAP_WB);

	if (!log_tbl) {

		pr_err("Could not map UEFI TPM log table !\n");

		return -ENOMEM;

	}



	log_size = log_tbl->size;

	memunmap(log_tbl);



	log_tbl = memremap(efi.tpm_log, sizeof(*log_tbl) + log_size,

			   MEMREMAP_WB);

	if (!log_tbl) {

		pr_err("Could not map UEFI TPM log table payload!\n");

		return -ENOMEM;

	}



	/* malloc EventLog space */

	log->bios_event_log = kmalloc(log_size, GFP_KERNEL);

	if (!log->bios_event_log)

		goto err_memunmap;

	memcpy(log->bios_event_log, log_tbl->log, log_size);

	log->bios_event_log_end = log->bios_event_log + log_size;



	tpm_log_version = log_tbl->version;

	memunmap(log_tbl);

	return tpm_log_version;



err_memunmap:

	memunmap(log_tbl);

	return -ENOMEM;

}