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: Thiebaud Weksteen <tweek@google.com>
Reviewed-by: Jason Gunthorpe <jgunthorpe@obsidianresearch.com>
Reviewed-by: Javier Martinez Canillas <javierm@redhat.com>
Tested-by: Javier Martinez Canillas <javierm@redhat.com>
Tested-by: Jarkko Sakkinen  <jarkko.sakkinen@linux.intel.com>
Reviewed-by: Jarkko Sakkinen  <jarkko.sakkinen@linux.intel.com>
Signed-off-by: Jarkko Sakkinen  <jarkko.sakkinen@linux.intel.com>

diff --git a/drivers/char/tpm/Makefile b/drivers/char/tpm/Makefile
index bce9e1402e8755269c7993740ae1ffb527212259..acd758381c58ba37f992b8b0f7fcff48e202092c 100644 (file)
--- a/drivers/char/tpm/Makefile
+++ b/drivers/char/tpm/Makefile
@@ -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

diff --git a/drivers/char/tpm/tpm.h b/drivers/char/tpm/tpm.h
index d0f15c760fc7621aca6e2c73a46d6ee05e6c314a..c1866cc02e30bd63a61b872250284322d9ec3d3a 100644 (file)
--- a/drivers/char/tpm/tpm.h
+++ b/drivers/char/tpm/tpm.h
@@ -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);

diff --git a/drivers/char/tpm/tpm1_eventlog.c b/drivers/char/tpm/tpm1_eventlog.c
index d6f70f365443b582288ddc89efda074cce8ba439..add798bd69d0f176cdd175f60268abd3f6a8b1d8 100644 (file)
--- a/drivers/char/tpm/tpm1_eventlog.c
+++ b/drivers/char/tpm/tpm1_eventlog.c
@@ -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

diff --git a/drivers/char/tpm/tpm_eventlog_acpi.c b/drivers/char/tpm/tpm_eventlog_acpi.c
index acc990ba376a9d8fd3e90cb66ad62be93120b7ec..66f19e93c216c626721925c26a2fe5542eaf8443 100644 (file)
--- a/drivers/char/tpm/tpm_eventlog_acpi.c
+++ b/drivers/char/tpm/tpm_eventlog_acpi.c
@@ -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);

diff --git a/drivers/char/tpm/tpm_eventlog_efi.c b/drivers/char/tpm/tpm_eventlog_efi.c
new file mode 100644 (file)
index 0000000..e3f9ffd
--- /dev/null
+++ b/drivers/char/tpm/tpm_eventlog_efi.c
@@ -0,0 +1,66 @@
+/*
+ * 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;
+}

diff --git a/drivers/char/tpm/tpm_eventlog_of.c b/drivers/char/tpm/tpm_eventlog_of.c
index 4a2f8c79231ed4165ba602d78647da7cac483518..96fd5646f866d96bc4ed23eeea98c778e3173aef 100644 (file)
--- a/drivers/char/tpm/tpm_eventlog_of.c
+++ b/drivers/char/tpm/tpm_eventlog_of.c
@@ -76,5 +76,7 @@ int tpm_read_log_of(struct tpm_chip *chip)
 
        memcpy(log->bios_event_log, __va(base), size);
 
-       return 0;
+       if (chip->flags & TPM_CHIP_FLAG_TPM2)
+               return EFI_TCG2_EVENT_LOG_FORMAT_TCG_2;
+       return EFI_TCG2_EVENT_LOG_FORMAT_TCG_1_2;
 }