blob: 727bdf5f378a51f86048863a44f37905746408fe [file] [log] [blame]
/*
* Copyright (c) 2020, Arm Limited. All rights reserved.
*
* SPDX-License-Identifier: BSD-3-Clause
*/
#include <assert.h>
#include <errno.h>
#include <string.h>
#include <arch_helpers.h>
#include <common/bl_common.h>
#include <common/debug.h>
#include <drivers/auth/crypto_mod.h>
#include <drivers/measured_boot/event_log.h>
#include <mbedtls/md.h>
#include <plat/common/platform.h>
/* Event Log data */
static uint8_t event_log[EVENT_LOG_SIZE];
/* End of Event Log */
#define EVENT_LOG_END ((uintptr_t)event_log + sizeof(event_log) - 1U)
CASSERT(sizeof(event_log) >= LOG_MIN_SIZE, assert_event_log_size);
/* Pointer in event_log[] */
static uint8_t *log_ptr = event_log;
/* Pointer to measured_boot_data_t */
const static measured_boot_data_t *plat_data_ptr;
static uintptr_t tos_fw_config_base;
static uintptr_t nt_fw_config_base;
/* TCG_EfiSpecIdEvent */
static const id_event_headers_t id_event_header = {
.header = {
.pcr_index = PCR_0,
.event_type = EV_NO_ACTION,
.digest = {0},
.event_size = (uint32_t)(sizeof(id_event_struct_t) +
(sizeof(id_event_algorithm_size_t) *
HASH_ALG_COUNT))
},
.struct_header = {
.signature = TCG_ID_EVENT_SIGNATURE_03,
.platform_class = PLATFORM_CLASS_CLIENT,
.spec_version_minor = TCG_SPEC_VERSION_MINOR_TPM2,
.spec_version_major = TCG_SPEC_VERSION_MAJOR_TPM2,
.spec_errata = TCG_SPEC_ERRATA_TPM2,
.uintn_size = (uint8_t)(sizeof(unsigned int) /
sizeof(uint32_t)),
.number_of_algorithms = HASH_ALG_COUNT
}
};
static const event2_header_t locality_event_header = {
/*
* All EV_NO_ACTION events SHALL set
* TCG_PCR_EVENT2.pcrIndex = 0, unless otherwise specified
*/
.pcr_index = PCR_0,
/*
* All EV_NO_ACTION events SHALL set
* TCG_PCR_EVENT2.eventType = 03h
*/
.event_type = EV_NO_ACTION,
/*
* All EV_NO_ACTION events SHALL set
* TCG_PCR_EVENT2.digests to all
* 0x00's for each allocated Hash algorithm
*/
.digests = {
.count = HASH_ALG_COUNT
}
};
/* Platform's table with platform specific image IDs, names and PCRs */
static const image_data_t plat_images_data[] = {
{ BL2_IMAGE_ID, BL2_STRING, PCR_0 }, /* Reserved for BL2 */
{ INVALID_ID, NULL, (unsigned int)(-1) } /* Terminator */
};
static const measured_boot_data_t plat_measured_boot_data = {
plat_images_data,
NULL, /* platform_set_nt_fw_info */
NULL /* platform_set_tos_fw_info */
};
/*
* Function retuns pointer to platform's measured_boot_data_t structure
*
* Must be overridden in the platform code
*/
#pragma weak plat_get_measured_boot_data
const measured_boot_data_t *plat_get_measured_boot_data(void)
{
return &plat_measured_boot_data;
}
/*
* Add TCG_PCR_EVENT2 event
*
* @param[in] hash Pointer to hash data of TCG_DIGEST_SIZE bytes
* @param[in] image_ptr Pointer to image_data_t structure
* @return:
* 0 = success
* < 0 = error code
*/
static int add_event2(const uint8_t *hash, const image_data_t *image_ptr)
{
void *ptr = log_ptr;
uint32_t name_len;
uint32_t size_of_event;
assert(image_ptr != NULL);
assert(image_ptr->name != NULL);
name_len = (uint32_t)strlen(image_ptr->name) + 1U;
size_of_event = name_len + (uint32_t)EVENT2_HDR_SIZE;
/* Check for space in Event Log buffer */
if (((uintptr_t)ptr + size_of_event) > EVENT_LOG_END) {
ERROR("%s(): Event Log is short of memory", __func__);
return -ENOMEM;
}
/*
* As per TCG specifications, firmware components that are measured
* into PCR[0] must be logged in the event log using the event type
* EV_POST_CODE.
*/
/* TCG_PCR_EVENT2.PCRIndex */
((event2_header_t *)ptr)->pcr_index = image_ptr->pcr;
/* TCG_PCR_EVENT2.EventType */
((event2_header_t *)ptr)->event_type = EV_POST_CODE;
/* TCG_PCR_EVENT2.Digests.Count */
ptr = (uint8_t *)ptr + offsetof(event2_header_t, digests);
((tpml_digest_values *)ptr)->count = HASH_ALG_COUNT;
/* TCG_PCR_EVENT2.Digests[] */
ptr = (uint8_t *)((uintptr_t)ptr +
offsetof(tpml_digest_values, digests));
/* TCG_PCR_EVENT2.Digests[].AlgorithmId */
((tpmt_ha *)ptr)->algorithm_id = TPM_ALG_ID;
/* TCG_PCR_EVENT2.Digests[].Digest[] */
ptr = (uint8_t *)((uintptr_t)ptr + offsetof(tpmt_ha, digest));
/* Check for space in Event Log buffer */
if (((uintptr_t)ptr + TCG_DIGEST_SIZE) > EVENT_LOG_END) {
ERROR("%s(): Event Log is short of memory", __func__);
return -ENOMEM;
}
if (hash == NULL) {
/* Get BL2 hash from DTB */
bl2_plat_get_hash(ptr);
} else {
/* Copy digest */
(void)memcpy(ptr, (const void *)hash, TCG_DIGEST_SIZE);
}
/* TCG_PCR_EVENT2.EventSize */
ptr = (uint8_t *)((uintptr_t)ptr + TCG_DIGEST_SIZE);
((event2_data_t *)ptr)->event_size = name_len;
/* Copy event data to TCG_PCR_EVENT2.Event */
(void)memcpy((void *)(((event2_data_t *)ptr)->event),
(const void *)image_ptr->name, name_len);
/* End of event data */
log_ptr = (uint8_t *)((uintptr_t)ptr +
offsetof(event2_data_t, event) + name_len);
return 0;
}
/*
* Init Event Log
*
* Initialises Event Log by writing Specification ID and
* Startup Locality events.
*/
void event_log_init(void)
{
const char locality_signature[] = TCG_STARTUP_LOCALITY_SIGNATURE;
const uint8_t *start_ptr;
void *ptr = event_log;
/* Get pointer to platform's measured_boot_data_t structure */
plat_data_ptr = plat_get_measured_boot_data();
/*
* Add Specification ID Event first
*
* Copy TCG_EfiSpecIDEventStruct structure header
*/
(void)memcpy(ptr, (const void *)&id_event_header,
sizeof(id_event_header));
ptr = (uint8_t *)((uintptr_t)ptr + sizeof(id_event_header));
/* TCG_EfiSpecIdEventAlgorithmSize structure */
((id_event_algorithm_size_t *)ptr)->algorithm_id = TPM_ALG_ID;
((id_event_algorithm_size_t *)ptr)->digest_size = TCG_DIGEST_SIZE;
ptr = (uint8_t *)((uintptr_t)ptr + sizeof(id_event_algorithm_size_t));
/*
* TCG_EfiSpecIDEventStruct.vendorInfoSize
* No vendor data
*/
((id_event_struct_data_t *)ptr)->vendor_info_size = 0;
ptr = (uint8_t *)((uintptr_t)ptr +
offsetof(id_event_struct_data_t, vendor_info));
if ((uintptr_t)ptr != ((uintptr_t)event_log + ID_EVENT_SIZE)) {
panic();
}
start_ptr = (uint8_t *)ptr;
/*
* The Startup Locality event should be placed in the log before
* any event which extends PCR[0].
*
* Ref. TCG PC Client Platform Firmware Profile 9.4.5.3
*/
/* Copy Startup Locality Event Header */
(void)memcpy(ptr, (const void *)&locality_event_header,
sizeof(locality_event_header));
ptr = (uint8_t *)((uintptr_t)ptr + sizeof(locality_event_header));
/* TCG_PCR_EVENT2.Digests[].AlgorithmId */
((tpmt_ha *)ptr)->algorithm_id = TPM_ALG_ID;
/* TCG_PCR_EVENT2.Digests[].Digest[] */
(void)memset(&((tpmt_ha *)ptr)->digest, 0, TPM_ALG_ID);
ptr = (uint8_t *)((uintptr_t)ptr +
offsetof(tpmt_ha, digest) + TCG_DIGEST_SIZE);
/* TCG_PCR_EVENT2.EventSize */
((event2_data_t *)ptr)->event_size =
(uint32_t)sizeof(startup_locality_event_t);
ptr = (uint8_t *)((uintptr_t)ptr + offsetof(event2_data_t, event));
/* TCG_EfiStartupLocalityEvent.Signature */
(void)memcpy(ptr, (const void *)locality_signature,
sizeof(TCG_STARTUP_LOCALITY_SIGNATURE));
/*
* TCG_EfiStartupLocalityEvent.StartupLocality = 0:
* the platform's boot firmware
*/
((startup_locality_event_t *)ptr)->startup_locality = 0U;
ptr = (uint8_t *)((uintptr_t)ptr + sizeof(startup_locality_event_t));
if ((uintptr_t)ptr != ((uintptr_t)start_ptr + LOC_EVENT_SIZE)) {
panic();
}
log_ptr = (uint8_t *)ptr;
/* Add BL2 event */
if (add_event2(NULL, plat_data_ptr->images_data) != 0) {
panic();
}
}
/*
* Calculate and write hash of image, configuration data, etc.
* to Event Log.
*
* @param[in] data_base Address of data
* @param[in] data_size Size of data
* @param[in] data_id Data ID
* @return:
* 0 = success
* < 0 = error
*/
int tpm_record_measurement(uintptr_t data_base, uint32_t data_size,
uint32_t data_id)
{
const image_data_t *data_ptr = plat_data_ptr->images_data;
unsigned char hash_data[MBEDTLS_MD_MAX_SIZE];
int rc;
/* Check if image_id is supported */
while (data_ptr->id != data_id) {
if ((data_ptr++)->id == INVALID_ID) {
ERROR("%s(): image_id %u not supported\n",
__func__, data_id);
return -EINVAL;
}
}
if (data_id == TOS_FW_CONFIG_ID) {
tos_fw_config_base = data_base;
} else if (data_id == NT_FW_CONFIG_ID) {
nt_fw_config_base = data_base;
} else {
/* No action */
}
/* Calculate hash */
rc = crypto_mod_calc_hash((unsigned int)MBEDTLS_MD_ID,
(void *)data_base, data_size, hash_data);
if (rc != 0) {
return rc;
}
return add_event2(hash_data, data_ptr);
}
/*
* Finalise Event Log
*
* @param[out] log_addr Pointer to return Event Log address
* @param[out] log_size Pointer to return Event Log size
* @return:
* 0 = success
* < 0 = error code
*/
int event_log_finalise(uint8_t **log_addr, size_t *log_size)
{
/* Event Log size */
size_t num_bytes = (uintptr_t)log_ptr - (uintptr_t)event_log;
int rc;
assert(log_addr != NULL);
assert(log_size != NULL);
if (nt_fw_config_base == 0UL) {
ERROR("%s(): %s_FW_CONFIG not loaded\n", __func__, "NT");
return -ENOENT;
}
/*
* Set Event Log data in NT_FW_CONFIG and
* get Event Log address in Non-Secure memory
*/
if (plat_data_ptr->set_nt_fw_info != NULL) {
/* Event Log address in Non-Secure memory */
uintptr_t ns_log_addr;
rc = plat_data_ptr->set_nt_fw_info(
nt_fw_config_base,
#ifdef SPD_opteed
(uintptr_t)event_log,
#endif
num_bytes, &ns_log_addr);
if (rc != 0) {
ERROR("%s(): Unable to update %s_FW_CONFIG\n",
__func__, "NT");
return rc;
}
/* Copy Event Log to Non-secure memory */
(void)memcpy((void *)ns_log_addr, (const void *)event_log,
num_bytes);
/* Ensure that the Event Log is visible in Non-secure memory */
flush_dcache_range(ns_log_addr, num_bytes);
/* Return Event Log address in Non-Secure memory */
*log_addr = (uint8_t *)ns_log_addr;
} else {
INFO("%s(): set_%s_fw_info not set\n", __func__, "nt");
/* Return Event Log address in Secure memory */
*log_addr = event_log;
}
if (tos_fw_config_base != 0UL) {
if (plat_data_ptr->set_tos_fw_info != NULL) {
/* Set Event Log data in TOS_FW_CONFIG */
rc = plat_data_ptr->set_tos_fw_info(
tos_fw_config_base,
(uintptr_t)event_log,
num_bytes);
if (rc != 0) {
ERROR("%s(): Unable to update %s_FW_CONFIG\n",
__func__, "TOS");
return rc;
}
} else {
INFO("%s(): set_%s_fw_info not set\n", __func__, "tos");
}
} else {
INFO("%s(): %s_FW_CONFIG not loaded\n", __func__, "TOS");
}
/* Ensure that the Event Log is visible in Secure memory */
flush_dcache_range((uintptr_t)event_log, num_bytes);
/* Return Event Log size */
*log_size = num_bytes;
return 0;
}