diff options
Diffstat (limited to 'drivers/firmware')
| -rw-r--r-- | drivers/firmware/efi/Makefile | 2 | ||||
| -rw-r--r-- | drivers/firmware/efi/efi.c | 4 | ||||
| -rw-r--r-- | drivers/firmware/efi/libstub/Makefile | 3 | ||||
| -rw-r--r-- | drivers/firmware/efi/libstub/tpm.c | 81 | ||||
| -rw-r--r-- | drivers/firmware/efi/tpm.c | 40 |
5 files changed, 127 insertions, 3 deletions
diff --git a/drivers/firmware/efi/Makefile b/drivers/firmware/efi/Makefile index a3e73d6e8a43..cb805374f4bc 100644 --- a/drivers/firmware/efi/Makefile +++ b/drivers/firmware/efi/Makefile @@ -11,7 +11,7 @@ KASAN_SANITIZE_runtime-wrappers.o := n obj-$(CONFIG_ACPI_BGRT) += efi-bgrt.o -obj-$(CONFIG_EFI) += efi.o vars.o reboot.o memattr.o +obj-$(CONFIG_EFI) += efi.o vars.o reboot.o memattr.o tpm.o obj-$(CONFIG_EFI) += capsule.o memmap.o obj-$(CONFIG_EFI_VARS) += efivars.o obj-$(CONFIG_EFI_ESRT) += esrt.o diff --git a/drivers/firmware/efi/efi.c b/drivers/firmware/efi/efi.c index 8ce70c2e73d5..cd42f66a7c85 100644 --- a/drivers/firmware/efi/efi.c +++ b/drivers/firmware/efi/efi.c @@ -52,6 +52,7 @@ struct efi __read_mostly efi = { .properties_table = EFI_INVALID_TABLE_ADDR, .mem_attr_table = EFI_INVALID_TABLE_ADDR, .rng_seed = EFI_INVALID_TABLE_ADDR, + .tpm_log = EFI_INVALID_TABLE_ADDR }; EXPORT_SYMBOL(efi); @@ -464,6 +465,7 @@ static __initdata efi_config_table_type_t common_tables[] = { {EFI_PROPERTIES_TABLE_GUID, "PROP", &efi.properties_table}, {EFI_MEMORY_ATTRIBUTES_TABLE_GUID, "MEMATTR", &efi.mem_attr_table}, {LINUX_EFI_RANDOM_SEED_TABLE_GUID, "RNG", &efi.rng_seed}, + {LINUX_EFI_TPM_EVENT_LOG_GUID, "TPMEventLog", &efi.tpm_log}, {NULL_GUID, NULL, NULL}, }; @@ -552,6 +554,8 @@ int __init efi_config_parse_tables(void *config_tables, int count, int sz, if (efi_enabled(EFI_MEMMAP)) efi_memattr_init(); + efi_tpm_eventlog_init(); + /* Parse the EFI Properties table if it exists */ if (efi.properties_table != EFI_INVALID_TABLE_ADDR) { efi_properties_table_t *tbl; diff --git a/drivers/firmware/efi/libstub/Makefile b/drivers/firmware/efi/libstub/Makefile index adaa4a964f0c..7b3ba40f0745 100644 --- a/drivers/firmware/efi/libstub/Makefile +++ b/drivers/firmware/efi/libstub/Makefile @@ -30,8 +30,7 @@ OBJECT_FILES_NON_STANDARD := y # Prevents link failures: __sanitizer_cov_trace_pc() is not linked in. KCOV_INSTRUMENT := n -lib-y := efi-stub-helper.o gop.o secureboot.o -lib-$(CONFIG_RESET_ATTACK_MITIGATION) += tpm.o +lib-y := efi-stub-helper.o gop.o secureboot.o tpm.o # include the stub's generic dependencies from lib/ when building for ARM/arm64 arm-deps-y := fdt_rw.c fdt_ro.c fdt_wip.c fdt.c fdt_empty_tree.c fdt_sw.c diff --git a/drivers/firmware/efi/libstub/tpm.c b/drivers/firmware/efi/libstub/tpm.c index 6224cdbc9669..da661bf8cb96 100644 --- a/drivers/firmware/efi/libstub/tpm.c +++ b/drivers/firmware/efi/libstub/tpm.c @@ -4,15 +4,18 @@ * Copyright (C) 2016 CoreOS, Inc * Copyright (C) 2017 Google, Inc. * Matthew Garrett <mjg59@google.com> + * Thiebaud Weksteen <tweek@google.com> * * This file is part of the Linux kernel, and is made available under the * terms of the GNU General Public License version 2. */ #include <linux/efi.h> +#include <linux/tpm_eventlog.h> #include <asm/efi.h> #include "efistub.h" +#ifdef CONFIG_RESET_ATTACK_MITIGATION static const efi_char16_t efi_MemoryOverWriteRequest_name[] = { 'M', 'e', 'm', 'o', 'r', 'y', 'O', 'v', 'e', 'r', 'w', 'r', 'i', 't', 'e', 'R', 'e', 'q', 'u', 'e', 's', 't', 'C', 'o', 'n', 't', 'r', 'o', @@ -56,3 +59,81 @@ void efi_enable_reset_attack_mitigation(efi_system_table_t *sys_table_arg) EFI_VARIABLE_BOOTSERVICE_ACCESS | EFI_VARIABLE_RUNTIME_ACCESS, sizeof(val), &val); } + +#endif + +void efi_retrieve_tpm2_eventlog_1_2(efi_system_table_t *sys_table_arg) +{ + efi_guid_t tcg2_guid = EFI_TCG2_PROTOCOL_GUID; + efi_guid_t linux_eventlog_guid = LINUX_EFI_TPM_EVENT_LOG_GUID; + efi_status_t status; + efi_physical_addr_t log_location, log_last_entry; + struct linux_efi_tpm_eventlog *log_tbl; + unsigned long first_entry_addr, last_entry_addr; + size_t log_size, last_entry_size; + efi_bool_t truncated; + void *tcg2_protocol; + + status = efi_call_early(locate_protocol, &tcg2_guid, NULL, + &tcg2_protocol); + if (status != EFI_SUCCESS) + return; + + status = efi_call_proto(efi_tcg2_protocol, get_event_log, tcg2_protocol, + EFI_TCG2_EVENT_LOG_FORMAT_TCG_1_2, + &log_location, &log_last_entry, &truncated); + if (status != EFI_SUCCESS) + return; + + if (!log_location) + return; + first_entry_addr = (unsigned long) log_location; + + /* + * We populate the EFI table even if the logs are empty. + */ + if (!log_last_entry) { + log_size = 0; + } else { + last_entry_addr = (unsigned long) log_last_entry; + /* + * get_event_log only returns the address of the last entry. + * We need to calculate its size to deduce the full size of + * the logs. + */ + last_entry_size = sizeof(struct tcpa_event) + + ((struct tcpa_event *) last_entry_addr)->event_size; + log_size = log_last_entry - log_location + last_entry_size; + } + + /* Allocate space for the logs and copy them. */ + status = efi_call_early(allocate_pool, EFI_LOADER_DATA, + sizeof(*log_tbl) + log_size, + (void **) &log_tbl); + + if (status != EFI_SUCCESS) { + efi_printk(sys_table_arg, + "Unable to allocate memory for event log\n"); + return; + } + + memset(log_tbl, 0, sizeof(*log_tbl) + log_size); + log_tbl->size = log_size; + log_tbl->version = EFI_TCG2_EVENT_LOG_FORMAT_TCG_1_2; + memcpy(log_tbl->log, (void *) first_entry_addr, log_size); + + status = efi_call_early(install_configuration_table, + &linux_eventlog_guid, log_tbl); + if (status != EFI_SUCCESS) + goto err_free; + return; + +err_free: + efi_call_early(free_pool, log_tbl); +} + +void efi_retrieve_tpm2_eventlog(efi_system_table_t *sys_table_arg) +{ + /* Only try to retrieve the logs in 1.2 format. */ + efi_retrieve_tpm2_eventlog_1_2(sys_table_arg); +} diff --git a/drivers/firmware/efi/tpm.c b/drivers/firmware/efi/tpm.c new file mode 100644 index 000000000000..0cbeb3d46b18 --- /dev/null +++ b/drivers/firmware/efi/tpm.c @@ -0,0 +1,40 @@ +/* + * Copyright (C) 2017 Google, Inc. + * 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 version 2 as + * published by the Free Software Foundation. + */ + +#include <linux/efi.h> +#include <linux/init.h> +#include <linux/memblock.h> + +#include <asm/early_ioremap.h> + +/* + * Reserve the memory associated with the TPM Event Log configuration table. + */ +int __init efi_tpm_eventlog_init(void) +{ + struct linux_efi_tpm_eventlog *log_tbl; + unsigned int tbl_size; + + if (efi.tpm_log == EFI_INVALID_TABLE_ADDR) + return 0; + + log_tbl = early_memremap(efi.tpm_log, sizeof(*log_tbl)); + if (!log_tbl) { + pr_err("Failed to map TPM Event Log table @ 0x%lx\n", + efi.tpm_log); + efi.tpm_log = EFI_INVALID_TABLE_ADDR; + return -ENOMEM; + } + + tbl_size = sizeof(*log_tbl) + log_tbl->size; + memblock_reserve(efi.tpm_log, tbl_size); + early_memunmap(log_tbl, sizeof(*log_tbl)); + return 0; +} + |