diff options
Diffstat (limited to 'tpm.c')
| -rw-r--r-- | tpm.c | 99 |
1 files changed, 80 insertions, 19 deletions
@@ -35,32 +35,79 @@ static BOOLEAN tpm_present(efi_tpm_protocol_t *tpm) return TRUE; } -static BOOLEAN tpm2_present(efi_tpm2_protocol_t *tpm) +static EFI_STATUS tpm2_get_caps(efi_tpm2_protocol_t *tpm, + EFI_TCG2_BOOT_SERVICE_CAPABILITY *caps, + BOOLEAN *old_caps) { EFI_STATUS status; - EFI_TCG2_BOOT_SERVICE_CAPABILITY caps; - EFI_TCG2_BOOT_SERVICE_CAPABILITY_1_0 *caps_1_0; - caps.Size = (UINT8)sizeof(caps); + caps->Size = (UINT8)sizeof(*caps); - status = uefi_call_wrapper(tpm->get_capability, 2, tpm, &caps); + status = uefi_call_wrapper(tpm->get_capability, 2, tpm, caps); if (status != EFI_SUCCESS) - return FALSE; + return status; - if (caps.StructureVersion.Major == 1 && - caps.StructureVersion.Minor == 0) { - caps_1_0 = (EFI_TCG2_BOOT_SERVICE_CAPABILITY_1_0 *)∩︀ - if (caps_1_0->TPMPresentFlag) - return TRUE; - } else { - if (caps.TPMPresentFlag) + if (caps->StructureVersion.Major == 1 && + caps->StructureVersion.Minor == 0) + *old_caps = TRUE; + + return EFI_SUCCESS; +} + +static BOOLEAN tpm2_present(EFI_TCG2_BOOT_SERVICE_CAPABILITY *caps, + BOOLEAN old_caps) +{ + TREE_BOOT_SERVICE_CAPABILITY *caps_1_0; + + if (old_caps) { + caps_1_0 = (TREE_BOOT_SERVICE_CAPABILITY *)caps; + if (caps_1_0->TrEEPresentFlag) return TRUE; } + if (caps->TPMPresentFlag) + return TRUE; + return FALSE; } +static inline EFI_TCG2_EVENT_LOG_BITMAP +tpm2_get_supported_logs(efi_tpm2_protocol_t *tpm, + EFI_TCG2_BOOT_SERVICE_CAPABILITY *caps, + BOOLEAN old_caps) +{ + if (old_caps) + return ((TREE_BOOT_SERVICE_CAPABILITY *)caps)->SupportedEventLogs; + + return caps->SupportedEventLogs; +} + +/* + * According to TCG EFI Protocol Specification for TPM 2.0 family, + * all events generated after the invocation of EFI_TCG2_GET_EVENT_LOG + * shall be stored in an instance of an EFI_CONFIGURATION_TABLE aka + * EFI TCG 2.0 final events table. Hence, it is necessary to trigger the + * internal switch through calling get_event_log() in order to allow + * to retrieve the logs from OS runtime. + */ +static EFI_STATUS trigger_tcg2_final_events_table(efi_tpm2_protocol_t *tpm2, + EFI_TCG2_EVENT_LOG_BITMAP supported_logs) +{ + EFI_TCG2_EVENT_LOG_FORMAT log_fmt; + EFI_PHYSICAL_ADDRESS start; + EFI_PHYSICAL_ADDRESS end; + BOOLEAN truncated; + + if (supported_logs & EFI_TCG2_EVENT_LOG_FORMAT_TCG_2) + log_fmt = EFI_TCG2_EVENT_LOG_FORMAT_TCG_2; + else + log_fmt = EFI_TCG2_EVENT_LOG_FORMAT_TCG_1_2; + + return uefi_call_wrapper(tpm2->get_event_log, 5, tpm2, log_fmt, + &start, &end, &truncated); +} + EFI_STATUS tpm_log_event(EFI_PHYSICAL_ADDRESS buf, UINTN size, UINT8 pcr, const CHAR8 *description) { @@ -71,11 +118,26 @@ EFI_STATUS tpm_log_event(EFI_PHYSICAL_ADDRESS buf, UINTN size, UINT8 pcr, status = LibLocateProtocol(&tpm2_guid, (VOID **)&tpm2); /* TPM 2.0 */ if (status == EFI_SUCCESS) { + BOOLEAN old_caps; EFI_TCG2_EVENT *event; + EFI_TCG2_BOOT_SERVICE_CAPABILITY caps; + EFI_TCG2_EVENT_LOG_BITMAP supported_logs; - if (!tpm2_present(tpm2)) + status = tpm2_get_caps(tpm2, &caps, &old_caps); + if (status != EFI_SUCCESS) + return EFI_SUCCESS; + + if (!tpm2_present(&caps, old_caps)) return EFI_SUCCESS; + supported_logs = tpm2_get_supported_logs(tpm2, &caps, old_caps); + + status = trigger_tcg2_final_events_table(tpm2, supported_logs); + if (EFI_ERROR(status)) { + perror(L"Unable to trigger tcg2 final events table: %r\n", status); + return status; + } + event = AllocatePool(sizeof(*event) + strlen(description) + 1); if (!event) { perror(L"Unable to allocate event structure\n"); @@ -85,7 +147,7 @@ EFI_STATUS tpm_log_event(EFI_PHYSICAL_ADDRESS buf, UINTN size, UINT8 pcr, event->Header.HeaderSize = sizeof(EFI_TCG2_EVENT_HEADER); event->Header.HeaderVersion = 1; event->Header.PCRIndex = pcr; - event->Header.EventType = 0x0d; + event->Header.EventType = EV_IPL; event->Size = sizeof(*event) - sizeof(event->Event) + strlen(description) + 1; memcpy(event->Event, description, strlen(description) + 1); status = uefi_call_wrapper(tpm2->hash_log_extend_event, 5, tpm2, @@ -94,7 +156,7 @@ EFI_STATUS tpm_log_event(EFI_PHYSICAL_ADDRESS buf, UINTN size, UINT8 pcr, return status; } else { TCG_PCR_EVENT *event; - UINT32 algorithm, eventnum = 0; + UINT32 eventnum = 0; EFI_PHYSICAL_ADDRESS lastevent; status = LibLocateProtocol(&tpm_guid, (VOID **)&tpm); @@ -113,11 +175,10 @@ EFI_STATUS tpm_log_event(EFI_PHYSICAL_ADDRESS buf, UINTN size, UINT8 pcr, } event->PCRIndex = pcr; - event->EventType = 0x0d; + event->EventType = EV_IPL; event->EventSize = strlen(description) + 1; - algorithm = 0x00000004; status = uefi_call_wrapper(tpm->log_extend_event, 7, tpm, buf, - (UINT64)size, algorithm, event, + (UINT64)size, TPM_ALG_SHA, event, &eventnum, &lastevent); FreePool(event); return status; |