From 58cc1e4faf10a73c4302825ffd37a47d410fc1b5 Mon Sep 17 00:00:00 2001 From: Thiebaud Weksteen Date: Wed, 20 Sep 2017 10:13:40 +0200 Subject: [PATCH] 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 Reviewed-by: Jason Gunthorpe Reviewed-by: Javier Martinez Canillas Tested-by: Javier Martinez Canillas Tested-by: Jarkko Sakkinen Reviewed-by: Jarkko Sakkinen Signed-off-by: Jarkko Sakkinen --- drivers/char/tpm/Makefile | 1 + drivers/char/tpm/tpm.h | 8 +++++ drivers/char/tpm/tpm1_eventlog.c | 11 ++++-- drivers/char/tpm/tpm_eventlog_acpi.c | 2 +- drivers/char/tpm/tpm_eventlog_efi.c | 66 ++++++++++++++++++++++++++++++++++++ drivers/char/tpm/tpm_eventlog_of.c | 4 ++- 6 files changed, 88 insertions(+), 4 deletions(-) create mode 100644 drivers/char/tpm/tpm_eventlog_efi.c diff --git a/drivers/char/tpm/Makefile b/drivers/char/tpm/Makefile index bce9e14..acd7583 100644 --- 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 d0f15c7..c1866cc 100644 --- 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 d6f70f3..add798b 100644 --- a/drivers/char/tpm/tpm1_eventlog.c +++ b/drivers/char/tpm/tpm1_eventlog.c @@ -21,6 +21,7 @@ */ #include +#include #include #include #include @@ -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 acc990b..66f19e9 100644 --- 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 index 0000000..e3f9ffd --- /dev/null +++ b/drivers/char/tpm/tpm_eventlog_efi.c @@ -0,0 +1,66 @@ +/* + * Copyright (C) 2017 Google + * + * Authors: + * Thiebaud Weksteen + * + * 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 +#include + +#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 4a2f8c7..96fd564 100644 --- 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; } -- 2.7.4