// SPDX-License-Identifier: GPL-2.0+ /* * Defines APIs that allow an OS to interact with UEFI firmware to query * information about the device. * https://trustedcomputinggroup.org/resource/tcg-efi-protocol-specification/ * * Copyright (c) 2020, Linaro Limited */ #define LOG_CATEGORY LOGC_EFI #include #include #include #include #include #include #include #include #include #include #include #include #include struct event_log_buffer { void *buffer; void *final_buffer; size_t pos; /* eventlog position */ size_t final_pos; /* final events config table position */ size_t last_event_size; bool get_event_called; bool truncated; }; static struct event_log_buffer event_log; /* * When requesting TPM2_CAP_TPM_PROPERTIES the value is on a standard offset. * Since the current tpm2_get_capability() response buffers starts at * 'union tpmu_capabilities data' of 'struct tpms_capability_data', calculate * the response size and offset once for all consumers */ #define TPM2_RESPONSE_BUFFER_SIZE (sizeof(struct tpms_capability_data) - \ offsetof(struct tpms_capability_data, data)) #define properties_offset (offsetof(struct tpml_tagged_tpm_property, tpm_property) + \ offsetof(struct tpms_tagged_property, value)) static const efi_guid_t efi_guid_tcg2_protocol = EFI_TCG2_PROTOCOL_GUID; static const efi_guid_t efi_guid_final_events = EFI_TCG2_FINAL_EVENTS_TABLE_GUID; struct digest_info { u16 hash_alg; u32 hash_mask; u16 hash_len; }; const static struct digest_info hash_algo_list[] = { { TPM2_ALG_SHA1, EFI_TCG2_BOOT_HASH_ALG_SHA1, TPM2_SHA1_DIGEST_SIZE, }, { TPM2_ALG_SHA256, EFI_TCG2_BOOT_HASH_ALG_SHA256, TPM2_SHA256_DIGEST_SIZE, }, { TPM2_ALG_SHA384, EFI_TCG2_BOOT_HASH_ALG_SHA384, TPM2_SHA384_DIGEST_SIZE, }, { TPM2_ALG_SHA512, EFI_TCG2_BOOT_HASH_ALG_SHA512, TPM2_SHA512_DIGEST_SIZE, }, }; #define MAX_HASH_COUNT ARRAY_SIZE(hash_algo_list) /** * alg_to_mask - Get a TCG hash mask for algorithms * * @hash_alg: TCG defined algorithm * * @Return: TCG hashing algorithm bitmaps, 0 if the algorithm is not supported */ static u32 alg_to_mask(u16 hash_alg) { int i; for (i = 0; i < MAX_HASH_COUNT; i++) { if (hash_algo_list[i].hash_alg == hash_alg) return hash_algo_list[i].hash_mask; } return 0; } /** * alg_to_len - Get a TCG hash len for algorithms * * @hash_alg: TCG defined algorithm * * @Return: len of chosen algorithm, 0 if the algorithm is not supported */ static u16 alg_to_len(u16 hash_alg) { int i; for (i = 0; i < MAX_HASH_COUNT; i++) { if (hash_algo_list[i].hash_alg == hash_alg) return hash_algo_list[i].hash_len; } return 0; } static u32 tcg_event_final_size(struct tpml_digest_values *digest_list) { u32 len; int i; len = offsetof(struct tcg_pcr_event2, digests); len += offsetof(struct tpml_digest_values, digests); for (i = 0; i < digest_list->count; i++) { u16 hash_alg = digest_list->digests[i].hash_alg; len += offsetof(struct tpmt_ha, digest); len += alg_to_len(hash_alg); } len += sizeof(u32); /* tcg_pcr_event2 event_size*/ return len; } /* tcg2_pcr_extend - Extend PCRs for a TPM2 device for a given tpml_digest_values * * @dev: device * @digest_list: list of digest algorithms to extend * * @Return: status code */ static efi_status_t tcg2_pcr_extend(struct udevice *dev, u32 pcr_index, struct tpml_digest_values *digest_list) { u32 rc; int i; for (i = 0; i < digest_list->count; i++) { u32 alg = digest_list->digests[i].hash_alg; rc = tpm2_pcr_extend(dev, pcr_index, alg, (u8 *)&digest_list->digests[i].digest, alg_to_len(alg)); if (rc) { EFI_PRINT("Failed to extend PCR\n"); return EFI_DEVICE_ERROR; } } return EFI_SUCCESS; } /* tcg2_agile_log_append - Append an agile event to out eventlog * * @pcr_index: PCR index * @event_type: type of event added * @digest_list: list of digest algorithms to add * @size: size of event * @event: event to add * * @Return: status code */ static efi_status_t tcg2_agile_log_append(u32 pcr_index, u32 event_type, struct tpml_digest_values *digest_list, u32 size, u8 event[]) { void *log = (void *)((uintptr_t)event_log.buffer + event_log.pos); size_t pos; int i; u32 event_size; if (event_log.get_event_called) log = (void *)((uintptr_t)event_log.final_buffer + event_log.final_pos); /* * size refers to the length of event[] only, we need to check against * the final tcg_pcr_event2 size */ event_size = size + tcg_event_final_size(digest_list); if (event_log.pos + event_size > TPM2_EVENT_LOG_SIZE || event_log.final_pos + event_size > TPM2_EVENT_LOG_SIZE) { event_log.truncated = true; return EFI_VOLUME_FULL; } put_unaligned_le32(pcr_index, log); pos = offsetof(struct tcg_pcr_event2, event_type); put_unaligned_le32(event_type, (void *)((uintptr_t)log + pos)); pos = offsetof(struct tcg_pcr_event2, digests); /* count */ put_unaligned_le32(digest_list->count, (void *)((uintptr_t)log + pos)); pos += offsetof(struct tpml_digest_values, digests); for (i = 0; i < digest_list->count; i++) { u16 hash_alg = digest_list->digests[i].hash_alg; u8 *digest = (u8 *)&digest_list->digests[i].digest; put_unaligned_le16(hash_alg, (void *)((uintptr_t)log + pos)); pos += offsetof(struct tpmt_ha, digest); memcpy((void *)((uintptr_t)log + pos), digest, alg_to_len(hash_alg)); pos += alg_to_len(hash_alg); } put_unaligned_le32(size, (void *)((uintptr_t)log + pos)); pos += sizeof(u32); /* tcg_pcr_event2 event_size*/ memcpy((void *)((uintptr_t)log + pos), event, size); pos += size; /* make sure the calculated buffer is what we checked against */ if (pos != event_size) return EFI_INVALID_PARAMETER; /* if GetEventLog hasn't been called update the normal log */ if (!event_log.get_event_called) { event_log.pos += pos; event_log.last_event_size = pos; } else { /* if GetEventLog has been called update config table log */ struct efi_tcg2_final_events_table *final_event; final_event = (struct efi_tcg2_final_events_table *)(event_log.final_buffer); final_event->number_of_events++; event_log.final_pos += pos; } return EFI_SUCCESS; } /** * platform_get_tpm_device() - retrieve TPM device * * This function retrieves the udevice implementing a TPM * * This function may be overridden if special initialization is needed. * * @dev: udevice * Return: status code */ __weak efi_status_t platform_get_tpm2_device(struct udevice **dev) { for_each_tpm_device(*dev) { /* Only support TPMv2 devices */ if (tpm_get_version(*dev) == TPM_V2) return EFI_SUCCESS; } return EFI_NOT_FOUND; } /** * tpm2_get_max_command_size() - get the supported max command size * * @dev: TPM device * @max_command_size: output buffer for the size * * Return: 0 on success, -1 on error */ static int tpm2_get_max_command_size(struct udevice *dev, u16 *max_command_size) { u8 response[TPM2_RESPONSE_BUFFER_SIZE]; u32 ret; memset(response, 0, sizeof(response)); ret = tpm2_get_capability(dev, TPM2_CAP_TPM_PROPERTIES, TPM2_PT_MAX_COMMAND_SIZE, response, 1); if (ret) return -1; *max_command_size = (uint16_t)get_unaligned_be32(response + properties_offset); return 0; } /** * tpm2_get_max_response_size() - get the supported max response size * * @dev: TPM device * @max_response_size: output buffer for the size * * Return: 0 on success, -1 on error */ static int tpm2_get_max_response_size(struct udevice *dev, u16 *max_response_size) { u8 response[TPM2_RESPONSE_BUFFER_SIZE]; u32 ret; memset(response, 0, sizeof(response)); ret = tpm2_get_capability(dev, TPM2_CAP_TPM_PROPERTIES, TPM2_PT_MAX_RESPONSE_SIZE, response, 1); if (ret) return -1; *max_response_size = (uint16_t)get_unaligned_be32(response + properties_offset); return 0; } /** * tpm2_get_manufacturer_id() - get the manufacturer ID * * @dev: TPM device * @manufacturer_id: output buffer for the id * * Return: 0 on success, -1 on error */ static int tpm2_get_manufacturer_id(struct udevice *dev, u32 *manufacturer_id) { u8 response[TPM2_RESPONSE_BUFFER_SIZE]; u32 ret; memset(response, 0, sizeof(response)); ret = tpm2_get_capability(dev, TPM2_CAP_TPM_PROPERTIES, TPM2_PT_MANUFACTURER, response, 1); if (ret) return -1; *manufacturer_id = get_unaligned_be32(response + properties_offset); return 0; } /** * tpm2_get_num_pcr() - get the number of PCRs * * @dev: TPM device * @manufacturer_id: output buffer for the number * * Return: 0 on success, -1 on error */ static int tpm2_get_num_pcr(struct udevice *dev, u32 *num_pcr) { u8 response[TPM2_RESPONSE_BUFFER_SIZE]; u32 ret; memset(response, 0, sizeof(response)); ret = tpm2_get_capability(dev, TPM2_CAP_TPM_PROPERTIES, TPM2_PT_PCR_COUNT, response, 1); if (ret) return -1; *num_pcr = get_unaligned_be32(response + properties_offset); if (*num_pcr > TPM2_MAX_PCRS) return -1; return 0; } /** * is_active_pcr() - Check if a supported algorithm is active * * @dev: TPM device * @selection: struct of PCR information * * Return: true if PCR is active */ static bool is_active_pcr(struct tpms_pcr_selection *selection) { int i; /* * check the pcr_select. If at least one of the PCRs supports the * algorithm add it on the active ones */ for (i = 0; i < selection->size_of_select; i++) { if (selection->pcr_select[i]) return true; } return false; } /** * tpm2_get_pcr_info() - get the supported, active PCRs and number of banks * * @dev: TPM device * @supported_pcr: bitmask with the algorithms supported * @active_pcr: bitmask with the active algorithms * @pcr_banks: number of PCR banks * * Return: 0 on success, -1 on error */ static int tpm2_get_pcr_info(struct udevice *dev, u32 *supported_pcr, u32 *active_pcr, u32 *pcr_banks) { u8 response[TPM2_RESPONSE_BUFFER_SIZE]; struct tpml_pcr_selection pcrs; u32 ret, num_pcr; int i, tpm_ret; memset(response, 0, sizeof(response)); ret = tpm2_get_capability(dev, TPM2_CAP_PCRS, 0, response, 1); if (ret) goto out; pcrs.count = get_unaligned_be32(response); /* * We only support 5 algorithms for now so check against that * instead of TPM2_NUM_PCR_BANKS */ if (pcrs.count > MAX_HASH_COUNT || pcrs.count < 1) goto out; tpm_ret = tpm2_get_num_pcr(dev, &num_pcr); if (tpm_ret) goto out; for (i = 0; i < pcrs.count; i++) { /* * Definition of TPMS_PCR_SELECTION Structure * hash: u16 * size_of_select: u8 * pcr_select: u8 array * * The offsets depend on the number of the device PCRs * so we have to calculate them based on that */ u32 hash_offset = offsetof(struct tpml_pcr_selection, selection) + i * offsetof(struct tpms_pcr_selection, pcr_select) + i * ((num_pcr + 7) / 8); u32 size_select_offset = hash_offset + offsetof(struct tpms_pcr_selection, size_of_select); u32 pcr_select_offset = hash_offset + offsetof(struct tpms_pcr_selection, pcr_select); pcrs.selection[i].hash = get_unaligned_be16(response + hash_offset); pcrs.selection[i].size_of_select = __get_unaligned_be(response + size_select_offset); if (pcrs.selection[i].size_of_select > TPM2_PCR_SELECT_MAX) goto out; /* copy the array of pcr_select */ memcpy(pcrs.selection[i].pcr_select, response + pcr_select_offset, pcrs.selection[i].size_of_select); } for (i = 0; i < pcrs.count; i++) { u32 hash_mask = alg_to_mask(pcrs.selection[i].hash); if (hash_mask) { *supported_pcr |= hash_mask; if (is_active_pcr(&pcrs.selection[i])) *active_pcr |= hash_mask; } else { EFI_PRINT("Unknown algorithm %x\n", pcrs.selection[i].hash); } } *pcr_banks = pcrs.count; return 0; out: return -1; } /** * __get_active_pcr_banks() - returns the currently active PCR banks * * @active_pcr_banks: pointer for receiving the bitmap of currently * active PCR banks * * Return: status code */ static efi_status_t __get_active_pcr_banks(u32 *active_pcr_banks) { struct udevice *dev; u32 active, supported, pcr_banks; efi_status_t ret; int err; ret = platform_get_tpm2_device(&dev); if (ret != EFI_SUCCESS) goto out; err = tpm2_get_pcr_info(dev, &supported, &active, &pcr_banks); if (err) { ret = EFI_DEVICE_ERROR; goto out; } *active_pcr_banks = active; out: return ret; } /* tcg2_create_digest - create a list of digests of the supported PCR banks * for a given memory range * * @input: input memory * @length: length of buffer to calculate the digest * @digest_list: list of digests to fill in * * Return: status code */ static efi_status_t tcg2_create_digest(const u8 *input, u32 length, struct tpml_digest_values *digest_list) { sha1_context ctx; sha256_context ctx_256; sha512_context ctx_512; u8 final[TPM2_SHA512_DIGEST_SIZE]; efi_status_t ret; u32 active; int i; ret = __get_active_pcr_banks(&active); if (ret != EFI_SUCCESS) return ret; digest_list->count = 0; for (i = 0; i < MAX_HASH_COUNT; i++) { u16 hash_alg = hash_algo_list[i].hash_alg; if (!(active & alg_to_mask(hash_alg))) continue; switch (hash_alg) { case TPM2_ALG_SHA1: sha1_starts(&ctx); sha1_update(&ctx, input, length); sha1_finish(&ctx, final); break; case TPM2_ALG_SHA256: sha256_starts(&ctx_256); sha256_update(&ctx_256, input, length); sha256_finish(&ctx_256, final); break; case TPM2_ALG_SHA384: sha384_starts(&ctx_512); sha384_update(&ctx_512, input, length); sha384_finish(&ctx_512, final); break; case TPM2_ALG_SHA512: sha512_starts(&ctx_512); sha512_update(&ctx_512, input, length); sha512_finish(&ctx_512, final); break; default: EFI_PRINT("Unsupported algorithm %x\n", hash_alg); return EFI_INVALID_PARAMETER; } digest_list->count++; digest_list->digests[i].hash_alg = hash_alg; memcpy(&digest_list->digests[i].digest, final, (u32)alg_to_len(hash_alg)); } return EFI_SUCCESS; } /** * efi_tcg2_get_capability() - protocol capability information and state information * * @this: TCG2 protocol instance * @capability: caller allocated memory with size field to the size of * the structure allocated * Return: status code */ static efi_status_t EFIAPI efi_tcg2_get_capability(struct efi_tcg2_protocol *this, struct efi_tcg2_boot_service_capability *capability) { struct udevice *dev; efi_status_t efi_ret; int ret; EFI_ENTRY("%p, %p", this, capability); if (!this || !capability) { efi_ret = EFI_INVALID_PARAMETER; goto out; } if (capability->size < boot_service_capability_min) { capability->size = boot_service_capability_min; efi_ret = EFI_BUFFER_TOO_SMALL; goto out; } if (capability->size < sizeof(*capability)) { capability->size = sizeof(*capability); efi_ret = EFI_BUFFER_TOO_SMALL; goto out; } capability->structure_version.major = 1; capability->structure_version.minor = 1; capability->protocol_version.major = 1; capability->protocol_version.minor = 1; efi_ret = platform_get_tpm2_device(&dev); if (efi_ret != EFI_SUCCESS) { capability->supported_event_logs = 0; capability->hash_algorithm_bitmap = 0; capability->tpm_present_flag = false; capability->max_command_size = 0; capability->max_response_size = 0; capability->manufacturer_id = 0; capability->number_of_pcr_banks = 0; capability->active_pcr_banks = 0; efi_ret = EFI_SUCCESS; goto out; } /* We only allow a TPMv2 device to register the EFI protocol */ capability->supported_event_logs = TCG2_EVENT_LOG_FORMAT_TCG_2; capability->tpm_present_flag = true; /* Supported and active PCRs */ capability->hash_algorithm_bitmap = 0; capability->active_pcr_banks = 0; ret = tpm2_get_pcr_info(dev, &capability->hash_algorithm_bitmap, &capability->active_pcr_banks, &capability->number_of_pcr_banks); if (ret) { efi_ret = EFI_DEVICE_ERROR; goto out; } /* Max command size */ ret = tpm2_get_max_command_size(dev, &capability->max_command_size); if (ret) { efi_ret = EFI_DEVICE_ERROR; goto out; } /* Max response size */ ret = tpm2_get_max_response_size(dev, &capability->max_response_size); if (ret) { efi_ret = EFI_DEVICE_ERROR; goto out; } /* Manufacturer ID */ ret = tpm2_get_manufacturer_id(dev, &capability->manufacturer_id); if (ret) { efi_ret = EFI_DEVICE_ERROR; goto out; } return EFI_EXIT(EFI_SUCCESS); out: return EFI_EXIT(efi_ret); } /** * efi_tcg2_get_eventlog() - retrieve the the address of an event log and its * last entry * * @this: TCG2 protocol instance * @log_format: type of event log format * @event_log_location: pointer to the memory address of the event log * @event_log_last_entry: pointer to the address of the start of the last * entry in the event log in memory, if log contains * more than 1 entry * @event_log_truncated: set to true, if the Event Log is missing at i * least one entry * * Return: status code */ static efi_status_t EFIAPI efi_tcg2_get_eventlog(struct efi_tcg2_protocol *this, efi_tcg_event_log_format log_format, u64 *event_log_location, u64 *event_log_last_entry, bool *event_log_truncated) { efi_status_t ret = EFI_SUCCESS; struct udevice *dev; EFI_ENTRY("%p, %u, %p, %p, %p", this, log_format, event_log_location, event_log_last_entry, event_log_truncated); ret = platform_get_tpm2_device(&dev); if (ret != EFI_SUCCESS) { event_log_location = NULL; event_log_last_entry = NULL; *event_log_truncated = false; ret = EFI_SUCCESS; goto out; } *event_log_location = (uintptr_t)event_log.buffer; *event_log_last_entry = (uintptr_t)(event_log.buffer + event_log.pos - event_log.last_event_size); *event_log_truncated = event_log.truncated; event_log.get_event_called = true; out: return EFI_EXIT(ret); } /** * efi_tcg2_hash_log_extend_event() - extend and optionally log events * * @this: TCG2 protocol instance * @flags: bitmap providing additional information on the * operation * @data_to_hash: physical address of the start of the data buffer * to be hashed * @data_to_hash_len: the length in bytes of the buffer referenced by * data_to_hash * @efi_tcg_event: pointer to data buffer containing information * about the event * * Return: status code */ static efi_status_t EFIAPI efi_tcg2_hash_log_extend_event(struct efi_tcg2_protocol *this, u64 flags, u64 data_to_hash, u64 data_to_hash_len, struct efi_tcg2_event *efi_tcg_event) { struct udevice *dev; efi_status_t ret; u32 event_type, pcr_index, event_size; struct tpml_digest_values digest_list; EFI_ENTRY("%p, %llu, %llu, %llu, %p", this, flags, data_to_hash, data_to_hash_len, efi_tcg_event); if (!this || !data_to_hash || !efi_tcg_event) { ret = EFI_INVALID_PARAMETER; goto out; } ret = platform_get_tpm2_device(&dev); if (ret != EFI_SUCCESS) goto out; if (efi_tcg_event->size < efi_tcg_event->header.header_size + sizeof(u32)) { ret = EFI_INVALID_PARAMETER; goto out; } if (efi_tcg_event->header.pcr_index < 0 || efi_tcg_event->header.pcr_index > TPM2_MAX_PCRS) { ret = EFI_INVALID_PARAMETER; goto out; } /* * if PE_COFF_IMAGE is set we need to make sure the image is not * corrupted, verify it and hash the PE/COFF image in accordance with * the procedure specified in "Calculating the PE Image Hash" * section of the "Windows Authenticode Portable Executable Signature * Format" * Not supported for now */ if (flags & PE_COFF_IMAGE) { ret = EFI_UNSUPPORTED; goto out; } pcr_index = efi_tcg_event->header.pcr_index; event_type = efi_tcg_event->header.event_type; ret = tcg2_create_digest((u8 *)(uintptr_t)data_to_hash, data_to_hash_len, &digest_list); if (ret != EFI_SUCCESS) goto out; ret = tcg2_pcr_extend(dev, pcr_index, &digest_list); if (ret != EFI_SUCCESS) goto out; if (flags & EFI_TCG2_EXTEND_ONLY) { if (event_log.truncated) ret = EFI_VOLUME_FULL; goto out; } /* * The efi_tcg_event size includes the size component and the * headersize */ event_size = efi_tcg_event->size - sizeof(efi_tcg_event->size) - efi_tcg_event->header.header_size; ret = tcg2_agile_log_append(pcr_index, event_type, &digest_list, event_size, efi_tcg_event->event); out: return EFI_EXIT(ret); } /** * efi_tcg2_submit_command() - Send command to the TPM * * @this: TCG2 protocol instance * @input_param_block_size: size of the TPM input parameter block * @input_param_block: pointer to the TPM input parameter block * @output_param_block_size: size of the TPM output parameter block * @output_param_block: pointer to the TPM output parameter block * * Return: status code */ static efi_status_t EFIAPI efi_tcg2_submit_command(struct efi_tcg2_protocol *this, u32 input_param_block_size, u8 *input_param_block, u32 output_param_block_size, u8 *output_param_block) { return EFI_UNSUPPORTED; } /** * efi_tcg2_get_active_pcr_banks() - returns the currently active PCR banks * * @this: TCG2 protocol instance * @active_pcr_banks: pointer for receiving the bitmap of currently * active PCR banks * * Return: status code */ static efi_status_t EFIAPI efi_tcg2_get_active_pcr_banks(struct efi_tcg2_protocol *this, u32 *active_pcr_banks) { efi_status_t ret; EFI_ENTRY("%p, %p", this, active_pcr_banks); ret = __get_active_pcr_banks(active_pcr_banks); return EFI_EXIT(ret); } /** * efi_tcg2_set_active_pcr_banks() - sets the currently active PCR banks * * @this: TCG2 protocol instance * @active_pcr_banks: bitmap of the requested active PCR banks * * Return: status code */ static efi_status_t EFIAPI efi_tcg2_set_active_pcr_banks(struct efi_tcg2_protocol *this, u32 active_pcr_banks) { return EFI_UNSUPPORTED; } /** * efi_tcg2_get_result_of_set_active_pcr_banks() - retrieve result for previous * set_active_pcr_banks() * * @this: TCG2 protocol instance * @operation_present: non-zero value to indicate a * set_active_pcr_banks operation was * invoked during last boot * @response: result value could be returned * * Return: status code */ static efi_status_t EFIAPI efi_tcg2_get_result_of_set_active_pcr_banks(struct efi_tcg2_protocol *this, u32 *operation_present, u32 *response) { return EFI_UNSUPPORTED; } static const struct efi_tcg2_protocol efi_tcg2_protocol = { .get_capability = efi_tcg2_get_capability, .get_eventlog = efi_tcg2_get_eventlog, .hash_log_extend_event = efi_tcg2_hash_log_extend_event, .submit_command = efi_tcg2_submit_command, .get_active_pcr_banks = efi_tcg2_get_active_pcr_banks, .set_active_pcr_banks = efi_tcg2_set_active_pcr_banks, .get_result_of_set_active_pcr_banks = efi_tcg2_get_result_of_set_active_pcr_banks, }; /** * create_specid_event() - Create the first event in the eventlog * * @dev: tpm device * @event_header: Pointer to the final event header * @event_size: final spec event size * * Return: status code */ static efi_status_t create_specid_event(struct udevice *dev, void *buffer, size_t *event_size) { struct tcg_efi_spec_id_event *spec_event; size_t spec_event_size; efi_status_t ret = EFI_DEVICE_ERROR; u32 active, supported; int err, i; /* * Create Spec event. This needs to be the first event in the log * according to the TCG EFI protocol spec */ /* Setup specID event data */ spec_event = (struct tcg_efi_spec_id_event *)buffer; memcpy(spec_event->signature, TCG_EFI_SPEC_ID_EVENT_SIGNATURE_03, sizeof(spec_event->signature)); put_unaligned_le32(0, &spec_event->platform_class); /* type client */ spec_event->spec_version_minor = TCG_EFI_SPEC_ID_EVENT_SPEC_VERSION_MINOR_TPM2; spec_event->spec_version_major = TCG_EFI_SPEC_ID_EVENT_SPEC_VERSION_MAJOR_TPM2; spec_event->spec_errata = TCG_EFI_SPEC_ID_EVENT_SPEC_VERSION_ERRATA_TPM2; spec_event->uintn_size = sizeof(efi_uintn_t) / sizeof(u32); err = tpm2_get_pcr_info(dev, &supported, &active, &spec_event->number_of_algorithms); if (err) goto out; if (spec_event->number_of_algorithms > MAX_HASH_COUNT || spec_event->number_of_algorithms < 1) goto out; for (i = 0; i < spec_event->number_of_algorithms; i++) { u16 hash_alg = hash_algo_list[i].hash_alg; u16 hash_len = hash_algo_list[i].hash_len; if (active && alg_to_mask(hash_alg)) { put_unaligned_le16(hash_alg, &spec_event->digest_sizes[i].algorithm_id); put_unaligned_le16(hash_len, &spec_event->digest_sizes[i].digest_size); } } /* * the size of the spec event and placement of vendor_info_size * depends on supported algoriths */ spec_event_size = offsetof(struct tcg_efi_spec_id_event, digest_sizes) + spec_event->number_of_algorithms * sizeof(spec_event->digest_sizes[0]); /* no vendor info for us */ memset(buffer + spec_event_size, 0, sizeof(spec_event->vendor_info_size)); spec_event_size += sizeof(spec_event->vendor_info_size); *event_size = spec_event_size; return EFI_SUCCESS; out: return ret; } /** * tcg2_uninit - remove the final event table and free efi memory on failures */ void tcg2_uninit(void) { efi_status_t ret; ret = efi_install_configuration_table(&efi_guid_final_events, NULL); if (ret != EFI_SUCCESS) log_err("Failed to delete final events config table\n"); efi_free_pool(event_log.buffer); event_log.buffer = NULL; efi_free_pool(event_log.final_buffer); event_log.final_buffer = NULL; } /** * create_final_event() - Create the final event and install the config * defined by the TCG EFI spec */ static efi_status_t create_final_event(void) { struct efi_tcg2_final_events_table *final_event; efi_status_t ret; /* * All events generated after the invocation of * EFI_TCG2_GET_EVENT_LOGS need to be stored in an instance of an * EFI_CONFIGURATION_TABLE */ ret = efi_allocate_pool(EFI_ACPI_MEMORY_NVS, TPM2_EVENT_LOG_SIZE, &event_log.final_buffer); if (ret != EFI_SUCCESS) goto out; memset(event_log.final_buffer, 0xff, TPM2_EVENT_LOG_SIZE); final_event = event_log.final_buffer; final_event->number_of_events = 0; final_event->version = EFI_TCG2_FINAL_EVENTS_TABLE_VERSION; event_log.final_pos = sizeof(*final_event); ret = efi_install_configuration_table(&efi_guid_final_events, final_event); out: return ret; } /** * efi_init_event_log() - initialize an eventlog */ static efi_status_t efi_init_event_log(void) { /* * vendor_info_size is currently set to 0, we need to change the length * and allocate the flexible array member if this changes */ struct tcg_pcr_event *event_header = NULL; struct udevice *dev; size_t spec_event_size; efi_status_t ret; ret = platform_get_tpm2_device(&dev); if (ret != EFI_SUCCESS) goto out; ret = efi_allocate_pool(EFI_BOOT_SERVICES_DATA, TPM2_EVENT_LOG_SIZE, (void **)&event_log.buffer); if (ret != EFI_SUCCESS) goto out; /* * initialize log area as 0xff so the OS can easily figure out the * last log entry */ memset(event_log.buffer, 0xff, TPM2_EVENT_LOG_SIZE); event_log.pos = 0; event_log.last_event_size = 0; event_log.get_event_called = false; event_log.truncated = false; /* * The log header is defined to be in SHA1 event log entry format. * Setup event header */ event_header = (struct tcg_pcr_event *)event_log.buffer; put_unaligned_le32(0, &event_header->pcr_index); put_unaligned_le32(EV_NO_ACTION, &event_header->event_type); memset(&event_header->digest, 0, sizeof(event_header->digest)); ret = create_specid_event(dev, (void *)((uintptr_t)event_log.buffer + sizeof(*event_header)), &spec_event_size); if (ret != EFI_SUCCESS) goto out; put_unaligned_le32(spec_event_size, &event_header->event_size); event_log.pos = spec_event_size + sizeof(*event_header); event_log.last_event_size = event_log.pos; ret = create_final_event(); if (ret != EFI_SUCCESS) goto out; return EFI_SUCCESS; out: tcg2_uninit(); return ret; } /** * efi_append_scrtm_version - Append an S-CRTM EV_S_CRTM_VERSION event on the * eventlog and extend the PCRs * * @dev: TPM device * * @Return: status code */ static efi_status_t efi_append_scrtm_version(struct udevice *dev) { struct tpml_digest_values digest_list; u8 ver[] = U_BOOT_VERSION_STRING; const int pcr_index = 0; efi_status_t ret; ret = tcg2_create_digest(ver, sizeof(ver), &digest_list); if (ret != EFI_SUCCESS) goto out; ret = tcg2_pcr_extend(dev, pcr_index, &digest_list); if (ret != EFI_SUCCESS) goto out; ret = tcg2_agile_log_append(pcr_index, EV_S_CRTM_VERSION, &digest_list, sizeof(ver), ver); out: return ret; } /** * efi_tcg2_register() - register EFI_TCG2_PROTOCOL * * If a TPM2 device is available, the TPM TCG2 Protocol is registered * * Return: An error status is only returned if adding the protocol fails. */ efi_status_t efi_tcg2_register(void) { efi_status_t ret = EFI_SUCCESS; struct udevice *dev; ret = platform_get_tpm2_device(&dev); if (ret != EFI_SUCCESS) { log_warning("Unable to find TPMv2 device\n"); ret = EFI_SUCCESS; goto out; } ret = efi_init_event_log(); if (ret != EFI_SUCCESS) goto fail; ret = efi_append_scrtm_version(dev); if (ret != EFI_SUCCESS) goto out; ret = efi_add_protocol(efi_root, &efi_guid_tcg2_protocol, (void *)&efi_tcg2_protocol); if (ret != EFI_SUCCESS) { log_err("Cannot install EFI_TCG2_PROTOCOL\n"); goto fail; } out: return ret; fail: tcg2_uninit(); return ret; }