diff options
Diffstat (limited to 'drivers/measured_boot/event_log')
| -rw-r--r-- | drivers/measured_boot/event_log/event_log.c | 284 | ||||
| -rw-r--r-- | drivers/measured_boot/event_log/event_log.mk | 50 | ||||
| -rw-r--r-- | drivers/measured_boot/event_log/event_print.c | 265 |
3 files changed, 599 insertions, 0 deletions
diff --git a/drivers/measured_boot/event_log/event_log.c b/drivers/measured_boot/event_log/event_log.c new file mode 100644 index 000000000..1755dd95e --- /dev/null +++ b/drivers/measured_boot/event_log/event_log.c @@ -0,0 +1,284 @@ +/* + * Copyright (c) 2020-2021, 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/event_log.h> +#include <mbedtls/md.h> + +#include <plat/common/platform.h> + +/* Running Event Log Pointer */ +static uint8_t *log_ptr; + +/* Pointer to the first byte past end of the Event Log buffer */ +static uintptr_t log_end; + +/* Pointer to event_log_metadata_t */ +static const event_log_metadata_t *plat_metadata_ptr; + +/* 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 + } +}; + +/* + * Record a measurement as a TCG_PCR_EVENT2 event + * + * @param[in] hash Pointer to hash data of TCG_DIGEST_SIZE bytes + * @param[in] metadata_ptr Pointer to event_log_metadata_t structure + * + * There must be room for storing this new event into the event log buffer. + */ +static void event_log_record(const uint8_t *hash, + const event_log_metadata_t *metadata_ptr) +{ + void *ptr = log_ptr; + uint32_t name_len; + + assert(hash != NULL); + assert(metadata_ptr != NULL); + assert(metadata_ptr->name != NULL); + /* event_log_init() must have been called prior to this. */ + assert(log_ptr != NULL); + + name_len = (uint32_t)strlen(metadata_ptr->name) + 1U; + + /* Check for space in Event Log buffer */ + assert(((uintptr_t)ptr + (uint32_t)EVENT2_HDR_SIZE + name_len) < + log_end); + + /* + * 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 = metadata_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)); + + /* 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 *)metadata_ptr->name, name_len); + + /* End of event data */ + log_ptr = (uint8_t *)((uintptr_t)ptr + + offsetof(event2_data_t, event) + name_len); +} + +/* + * Initialise Event Log global variables, used during the recording + * of various payload measurements into the Event Log buffer + * + * @param[in] event_log_start Base address of Event Log buffer + * @param[in] event_log_finish End address of Event Log buffer, + * it is a first byte past end of the + * buffer + */ +void event_log_init(uint8_t *event_log_start, uint8_t *event_log_finish) +{ + assert(event_log_start != NULL); + assert(event_log_finish > event_log_start); + + log_ptr = event_log_start; + log_end = (uintptr_t)event_log_finish; + + /* Get pointer to platform's event_log_metadata_t structure */ + plat_metadata_ptr = plat_event_log_get_metadata(); + assert(plat_metadata_ptr != NULL); +} + +/* + * Initialises Event Log by writing Specification ID and + * Startup Locality events + */ +void event_log_write_header(void) +{ + const char locality_signature[] = TCG_STARTUP_LOCALITY_SIGNATURE; + void *ptr = log_ptr; + + /* event_log_init() must have been called prior to this. */ + assert(log_ptr != NULL); + + /* + * 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)); + + /* + * 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; + log_ptr = (uint8_t *)((uintptr_t)ptr + sizeof(startup_locality_event_t)); +} + +/* + * 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 event_log_measure_and_record(uintptr_t data_base, uint32_t data_size, + uint32_t data_id) +{ + unsigned char hash_data[MBEDTLS_MD_MAX_SIZE]; + int rc; + const event_log_metadata_t *metadata_ptr = plat_metadata_ptr; + + /* Get the metadata associated with this image. */ + while ((metadata_ptr->id != INVALID_ID) && + (metadata_ptr->id != data_id)) { + metadata_ptr++; + } + assert(metadata_ptr->id != INVALID_ID); + + /* Calculate hash */ + rc = crypto_mod_calc_hash((unsigned int)MBEDTLS_MD_ID, + (void *)data_base, data_size, hash_data); + if (rc != 0) { + return rc; + } + + event_log_record(hash_data, metadata_ptr); + + return 0; +} + +/* + * Get current Event Log buffer size i.e. used space of Event Log buffer + * + * @param[in] event_log_start Base Pointer to Event Log buffer + * + * @return: current Size of Event Log buffer + */ +size_t event_log_get_cur_size(uint8_t *event_log_start) +{ + assert(event_log_start != NULL); + assert(log_ptr >= event_log_start); + + return (size_t)((uintptr_t)log_ptr - (uintptr_t)event_log_start); +} diff --git a/drivers/measured_boot/event_log/event_log.mk b/drivers/measured_boot/event_log/event_log.mk new file mode 100644 index 000000000..37e5e291d --- /dev/null +++ b/drivers/measured_boot/event_log/event_log.mk @@ -0,0 +1,50 @@ +# +# Copyright (c) 2020-2021, Arm Limited. All rights reserved. +# +# SPDX-License-Identifier: BSD-3-Clause +# + +# Default log level to dump the event log (LOG_LEVEL_INFO) +EVENT_LOG_LEVEL ?= 40 + +# TPM hash algorithm. +# SHA-256 (or stronger) is required for all devices that are TPM 2.0 compliant. +TPM_HASH_ALG := sha256 + +ifeq (${TPM_HASH_ALG}, sha512) + MBEDTLS_MD_ID := MBEDTLS_MD_SHA512 + TPM_ALG_ID := TPM_ALG_SHA512 + TCG_DIGEST_SIZE := 64U +else ifeq (${TPM_HASH_ALG}, sha384) + MBEDTLS_MD_ID := MBEDTLS_MD_SHA384 + TPM_ALG_ID := TPM_ALG_SHA384 + TCG_DIGEST_SIZE := 48U +else + MBEDTLS_MD_ID := MBEDTLS_MD_SHA256 + TPM_ALG_ID := TPM_ALG_SHA256 + TCG_DIGEST_SIZE := 32U +endif + + +# Set definitions for mbed TLS library and Measured Boot driver +$(eval $(call add_defines,\ + $(sort \ + MBEDTLS_MD_ID \ + TPM_ALG_ID \ + TCG_DIGEST_SIZE \ + EVENT_LOG_LEVEL \ +))) + +ifeq (${HASH_ALG}, sha256) + ifneq (${TPM_HASH_ALG}, sha256) + $(eval $(call add_define,MBEDTLS_SHA512_C)) + endif +endif + +MEASURED_BOOT_SRC_DIR := drivers/measured_boot/event_log/ + +MEASURED_BOOT_SOURCES := ${MEASURED_BOOT_SRC_DIR}event_log.c \ + ${MEASURED_BOOT_SRC_DIR}event_print.c + +BL2_SOURCES += ${MEASURED_BOOT_SOURCES} +BL1_SOURCES += ${MEASURED_BOOT_SOURCES} diff --git a/drivers/measured_boot/event_log/event_print.c b/drivers/measured_boot/event_log/event_print.c new file mode 100644 index 000000000..e2ba1744d --- /dev/null +++ b/drivers/measured_boot/event_log/event_print.c @@ -0,0 +1,265 @@ +/* + * Copyright (c) 2020, Arm Limited. All rights reserved. + * + * SPDX-License-Identifier: BSD-3-Clause + */ + +#include <assert.h> +#include <string.h> + +#include <common/debug.h> +#include <drivers/measured_boot/event_log/event_log.h> + +#if LOG_LEVEL >= EVENT_LOG_LEVEL + +/* + * Print TCG_EfiSpecIDEventStruct + * + * @param[in/out] log_addr Pointer to Event Log + * @param[in/out] log_size Pointer to Event Log size + */ +static void id_event_print(uint8_t **log_addr, size_t *log_size) +{ + unsigned int i; + uint8_t info_size, *info_size_ptr; + void *ptr = *log_addr; + id_event_headers_t *event = (id_event_headers_t *)ptr; + id_event_algorithm_size_t *alg_ptr; + uint32_t event_size, number_of_algorithms; + size_t digest_len; +#if ENABLE_ASSERTIONS + const uint8_t *end_ptr = (uint8_t *)((uintptr_t)*log_addr + *log_size); + bool valid = true; +#endif + + assert(*log_size >= sizeof(id_event_headers_t)); + + /* The fields of the event log header are defined to be PCRIndex of 0, + * EventType of EV_NO_ACTION, Digest of 20 bytes of 0, and + * Event content defined as TCG_EfiSpecIDEventStruct. + */ + LOG_EVENT("TCG_EfiSpecIDEvent:\n"); + LOG_EVENT(" PCRIndex : %u\n", event->header.pcr_index); + assert(event->header.pcr_index == (uint32_t)PCR_0); + + LOG_EVENT(" EventType : %u\n", event->header.event_type); + assert(event->header.event_type == EV_NO_ACTION); + + LOG_EVENT(" Digest :"); + for (i = 0U; i < sizeof(event->header.digest); ++i) { + uint8_t val = event->header.digest[i]; + + (void)printf(" %02x", val); + if ((i & U(0xF)) == 0U) { + (void)printf("\n"); + LOG_EVENT("\t\t :"); + } +#if ENABLE_ASSERTIONS + if (val != 0U) { + valid = false; + } +#endif + } + if ((i & U(0xF)) != 0U) { + (void)printf("\n"); + } + + assert(valid); + + /* EventSize */ + event_size = event->header.event_size; + LOG_EVENT(" EventSize : %u\n", event_size); + + LOG_EVENT(" Signature : %s\n", + event->struct_header.signature); + LOG_EVENT(" PlatformClass : %u\n", + event->struct_header.platform_class); + LOG_EVENT(" SpecVersion : %u.%u.%u\n", + event->struct_header.spec_version_major, + event->struct_header.spec_version_minor, + event->struct_header.spec_errata); + LOG_EVENT(" UintnSize : %u\n", + event->struct_header.uintn_size); + + /* NumberOfAlgorithms */ + number_of_algorithms = event->struct_header.number_of_algorithms; + LOG_EVENT(" NumberOfAlgorithms : %u\n", number_of_algorithms); + + /* Address of DigestSizes[] */ + alg_ptr = event->struct_header.digest_size; + + /* Size of DigestSizes[] */ + digest_len = number_of_algorithms * sizeof(id_event_algorithm_size_t); + assert(((uintptr_t)alg_ptr + digest_len) <= (uintptr_t)end_ptr); + + LOG_EVENT(" DigestSizes :\n"); + for (i = 0U; i < number_of_algorithms; ++i) { + LOG_EVENT(" #%u AlgorithmId : SHA", i); + uint16_t algorithm_id = alg_ptr[i].algorithm_id; + + switch (algorithm_id) { + case TPM_ALG_SHA256: + (void)printf("256\n"); + break; + case TPM_ALG_SHA384: + (void)printf("384\n"); + break; + case TPM_ALG_SHA512: + (void)printf("512\n"); + break; + default: + (void)printf("?\n"); + ERROR("Algorithm 0x%x not found\n", algorithm_id); + assert(false); + } + + LOG_EVENT(" DigestSize : %u\n", + alg_ptr[i].digest_size); + } + + /* Address of VendorInfoSize */ + info_size_ptr = (uint8_t *)((uintptr_t)alg_ptr + digest_len); + assert((uintptr_t)info_size_ptr <= (uintptr_t)end_ptr); + + info_size = *info_size_ptr++; + LOG_EVENT(" VendorInfoSize : %u\n", info_size); + + /* Check VendorInfo end address */ + assert(((uintptr_t)info_size_ptr + info_size) <= (uintptr_t)end_ptr); + + /* Check EventSize */ + assert(event_size == (sizeof(id_event_struct_t) + + digest_len + info_size)); + if (info_size != 0U) { + LOG_EVENT(" VendorInfo :"); + for (i = 0U; i < info_size; ++i) { + (void)printf(" %02x", *info_size_ptr++); + } + (void)printf("\n"); + } + + *log_size -= (uintptr_t)info_size_ptr - (uintptr_t)*log_addr; + *log_addr = info_size_ptr; +} + +/* + * Print TCG_PCR_EVENT2 + * + * @param[in/out] log_addr Pointer to Event Log + * @param[in/out] log_size Pointer to Event Log size + */ +static void event2_print(uint8_t **log_addr, size_t *log_size) +{ + uint32_t event_size, count; + size_t sha_size, digests_size = 0U; + void *ptr = *log_addr; +#if ENABLE_ASSERTIONS + const uint8_t *end_ptr = (uint8_t *)((uintptr_t)*log_addr + *log_size); +#endif + + assert(*log_size >= sizeof(event2_header_t)); + + LOG_EVENT("PCR_Event2:\n"); + LOG_EVENT(" PCRIndex : %u\n", + ((event2_header_t *)ptr)->pcr_index); + LOG_EVENT(" EventType : %u\n", + ((event2_header_t *)ptr)->event_type); + + count = ((event2_header_t *)ptr)->digests.count; + LOG_EVENT(" Digests Count : %u\n", count); + + /* Address of TCG_PCR_EVENT2.Digests[] */ + ptr = (uint8_t *)ptr + sizeof(event2_header_t); + assert(((uintptr_t)ptr <= (uintptr_t)end_ptr) && (count != 0U)); + + for (unsigned int i = 0U; i < count; ++i) { + /* Check AlgorithmId address */ + assert(((uintptr_t)ptr + + offsetof(tpmt_ha, digest)) <= (uintptr_t)end_ptr); + + LOG_EVENT(" #%u AlgorithmId : SHA", i); + switch (((tpmt_ha *)ptr)->algorithm_id) { + case TPM_ALG_SHA256: + sha_size = SHA256_DIGEST_SIZE; + (void)printf("256\n"); + break; + case TPM_ALG_SHA384: + sha_size = SHA384_DIGEST_SIZE; + (void)printf("384\n"); + break; + case TPM_ALG_SHA512: + sha_size = SHA512_DIGEST_SIZE; + (void)printf("512\n"); + break; + default: + (void)printf("?\n"); + ERROR("Algorithm 0x%x not found\n", + ((tpmt_ha *)ptr)->algorithm_id); + panic(); + } + + /* End of Digest[] */ + ptr = (uint8_t *)((uintptr_t)ptr + offsetof(tpmt_ha, digest)); + assert(((uintptr_t)ptr + sha_size) <= (uintptr_t)end_ptr); + + /* Total size of all digests */ + digests_size += sha_size; + + LOG_EVENT(" Digest :"); + for (unsigned int j = 0U; j < sha_size; ++j) { + (void)printf(" %02x", *(uint8_t *)ptr++); + if ((j & U(0xF)) == U(0xF)) { + (void)printf("\n"); + if (j < (sha_size - 1U)) { + LOG_EVENT("\t\t :"); + } + } + } + } + + /* TCG_PCR_EVENT2.EventSize */ + assert(((uintptr_t)ptr + offsetof(event2_data_t, event)) <= (uintptr_t)end_ptr); + + event_size = ((event2_data_t *)ptr)->event_size; + LOG_EVENT(" EventSize : %u\n", event_size); + + /* Address of TCG_PCR_EVENT2.Event[EventSize] */ + ptr = (uint8_t *)((uintptr_t)ptr + offsetof(event2_data_t, event)); + + /* End of TCG_PCR_EVENT2.Event[EventSize] */ + assert(((uintptr_t)ptr + event_size) <= (uintptr_t)end_ptr); + + if ((event_size == sizeof(startup_locality_event_t)) && + (strcmp((const char *)ptr, TCG_STARTUP_LOCALITY_SIGNATURE) == 0)) { + LOG_EVENT(" Signature : %s\n", + ((startup_locality_event_t *)ptr)->signature); + LOG_EVENT(" StartupLocality : %u\n", + ((startup_locality_event_t *)ptr)->startup_locality); + } else { + LOG_EVENT(" Event : %s\n", (uint8_t *)ptr); + } + + *log_size -= (uintptr_t)ptr + event_size - (uintptr_t)*log_addr; + *log_addr = (uint8_t *)ptr + event_size; +} +#endif /* LOG_LEVEL >= EVENT_LOG_LEVEL */ + +/* + * Print Event Log + * + * @param[in] log_addr Pointer to Event Log + * @param[in] log_size Event Log size + */ +void dump_event_log(uint8_t *log_addr, size_t log_size) +{ +#if LOG_LEVEL >= EVENT_LOG_LEVEL + assert(log_addr != NULL); + + /* Print TCG_EfiSpecIDEvent */ + id_event_print(&log_addr, &log_size); + + while (log_size != 0U) { + event2_print(&log_addr, &log_size); + } +#endif +} |