TCG PC Client PFP spec requires to measure "Boot####" and "BootOrder" variables, EV_SEPARATOR event prior to the Ready to Boot invocation. Since u-boot does not implement Ready to Boot event, these measurements are performed when efi_start_image() is called.
TCG spec also requires to measure "Calling EFI Application from Boot Option" for each boot attempt, and "Returning from EFI Application from Boot Option" if a boot device returns control back to the Boot Manager.
Signed-off-by: Masahisa Kojima masahisa.kojima@linaro.org --- Changes in v4: - remove unnecessary EFIAPI specifier
Changes in v3: - modify log output
Changes in v2: - use efi_create_indexed_name() for "Boot####" variable
include/efi_loader.h | 4 ++ include/tpm-v2.h | 18 ++++- lib/efi_loader/efi_boottime.c | 20 ++++++ lib/efi_loader/efi_tcg2.c | 121 ++++++++++++++++++++++++++++++++++ 4 files changed, 162 insertions(+), 1 deletion(-)
diff --git a/include/efi_loader.h b/include/efi_loader.h index a120d94431..6f61e9faac 100644 --- a/include/efi_loader.h +++ b/include/efi_loader.h @@ -499,6 +499,10 @@ efi_status_t efi_run_image(void *source_buffer, efi_uintn_t source_size); efi_status_t efi_init_variables(void); /* Notify ExitBootServices() is called */ void efi_variables_boot_exit_notify(void); +/* Measure efi application invocation */ +efi_status_t efi_tcg2_measure_efi_app_invocation(void); +/* Measure efi application exit */ +efi_status_t efi_tcg2_measure_efi_app_exit(void); /* Called by bootefi to initialize root node */ efi_status_t efi_root_node_register(void); /* Called by bootefi to initialize runtime */ diff --git a/include/tpm-v2.h b/include/tpm-v2.h index 247b386967..325c73006e 100644 --- a/include/tpm-v2.h +++ b/include/tpm-v2.h @@ -73,7 +73,7 @@ struct udevice; /* * event types, cf. * "TCG PC Client Platform Firmware Profile Specification", Family "2.0" - * rev 1.04, June 3, 2019 + * Level 00 Version 1.05 Revision 23, May 7, 2021 */ #define EV_EFI_EVENT_BASE ((u32)0x80000000) #define EV_EFI_VARIABLE_DRIVER_CONFIG ((u32)0x80000001) @@ -85,8 +85,24 @@ struct udevice; #define EV_EFI_ACTION ((u32)0x80000007) #define EV_EFI_PLATFORM_FIRMWARE_BLOB ((u32)0x80000008) #define EV_EFI_HANDOFF_TABLES ((u32)0x80000009) +#define EV_EFI_PLATFORM_FIRMWARE_BLOB2 ((u32)0x8000000A) +#define EV_EFI_HANDOFF_TABLES2 ((u32)0x8000000B) +#define EV_EFI_VARIABLE_BOOT2 ((u32)0x8000000C) #define EV_EFI_HCRTM_EVENT ((u32)0x80000010) #define EV_EFI_VARIABLE_AUTHORITY ((u32)0x800000E0) +#define EV_EFI_SPDM_FIRMWARE_BLOB ((u32)0x800000E1) +#define EV_EFI_SPDM_FIRMWARE_CONFIG ((u32)0x800000E2) + +#define EFI_CALLING_EFI_APPLICATION \ + "Calling EFI Application from Boot Option" +#define EFI_RETURNING_FROM_EFI_APPLICATION \ + "Returning from EFI Application from Boot Option" +#define EFI_EXIT_BOOT_SERVICES_INVOCATION \ + "Exit Boot Services Invocation" +#define EFI_EXIT_BOOT_SERVICES_FAILED \ + "Exit Boot Services Returned with Failure" +#define EFI_EXIT_BOOT_SERVICES_SUCCEEDED \ + "Exit Boot Services Returned with Success"
/* TPMS_TAGGED_PROPERTY Structure */ struct tpms_tagged_property { diff --git a/lib/efi_loader/efi_boottime.c b/lib/efi_loader/efi_boottime.c index 0b98e91813..13ab139222 100644 --- a/lib/efi_loader/efi_boottime.c +++ b/lib/efi_loader/efi_boottime.c @@ -2994,6 +2994,16 @@ efi_status_t EFIAPI efi_start_image(efi_handle_t image_handle, image_obj->exit_status = &exit_status; image_obj->exit_jmp = &exit_jmp;
+ if (IS_ENABLED(CONFIG_EFI_TCG2_PROTOCOL)) { + if (image_obj->image_type == IMAGE_SUBSYSTEM_EFI_APPLICATION) { + ret = efi_tcg2_measure_efi_app_invocation(); + if (ret != EFI_SUCCESS) { + log_warning("tcg2 measurement fails(0x%lx)\n", + ret); + } + } + } + /* call the image! */ if (setjmp(&exit_jmp)) { /* @@ -3252,6 +3262,16 @@ static efi_status_t EFIAPI efi_exit(efi_handle_t image_handle, exit_status != EFI_SUCCESS) efi_delete_image(image_obj, loaded_image_protocol);
+ if (IS_ENABLED(CONFIG_EFI_TCG2_PROTOCOL)) { + if (image_obj->image_type == IMAGE_SUBSYSTEM_EFI_APPLICATION) { + ret = efi_tcg2_measure_efi_app_exit(); + if (ret != EFI_SUCCESS) { + log_warning("tcg2 measurement fails(0x%lx)\n", + ret); + } + } + } + /* Make sure entry/exit counts for EFI world cross-overs match */ EFI_EXIT(exit_status);
diff --git a/lib/efi_loader/efi_tcg2.c b/lib/efi_loader/efi_tcg2.c index db3d6d7586..ed71337780 100644 --- a/lib/efi_loader/efi_tcg2.c +++ b/lib/efi_loader/efi_tcg2.c @@ -35,6 +35,7 @@ struct event_log_buffer { };
static struct event_log_buffer event_log; +static bool tcg2_efi_app_invoked; /* * When requesting TPM2_CAP_TPM_PROPERTIES the value is on a standard offset. * Since the current tpm2_get_capability() response buffers starts at @@ -1385,6 +1386,126 @@ static efi_status_t tcg2_measure_variable(struct udevice *dev, u32 pcr_index, return ret; }
+/** + * tcg2_measure_boot_variable() - measure boot variables + * + * @dev: TPM device + * + * Return: status code + */ +static efi_status_t tcg2_measure_boot_variable(struct udevice *dev) +{ + u16 *boot_order; + u16 *boot_index; + u16 var_name[] = L"BootOrder"; + u16 boot_name[] = L"Boot####"; + u8 *bootvar; + efi_uintn_t var_data_size; + u32 count, i; + efi_status_t ret; + + boot_order = efi_get_var(var_name, &efi_global_variable_guid, + &var_data_size); + if (!boot_order) { + ret = EFI_NOT_FOUND; + goto error; + } + + ret = tcg2_measure_variable(dev, 1, EV_EFI_VARIABLE_BOOT2, var_name, + &efi_global_variable_guid, var_data_size, + (u8 *)boot_order); + if (ret != EFI_SUCCESS) + goto error; + + count = var_data_size / sizeof(*boot_order); + boot_index = boot_order; + for (i = 0; i < count; i++) { + efi_create_indexed_name(boot_name, sizeof(boot_name), + "Boot", *boot_index++); + + bootvar = efi_get_var(boot_name, &efi_global_variable_guid, + &var_data_size); + + if (!bootvar) { + log_info("%ls not found\n", boot_name); + continue; + } + + ret = tcg2_measure_variable(dev, 1, EV_EFI_VARIABLE_BOOT2, + boot_name, + &efi_global_variable_guid, + var_data_size, bootvar); + free(bootvar); + if (ret != EFI_SUCCESS) + goto error; + } + +error: + free(boot_order); + return ret; +} + +/** + * efi_tcg2_measure_efi_app_invocation() - measure efi app invocation + * + * Return: status code + */ +efi_status_t efi_tcg2_measure_efi_app_invocation(void) +{ + efi_status_t ret; + u32 pcr_index; + struct udevice *dev; + u32 event = 0; + + if (tcg2_efi_app_invoked) + return EFI_SUCCESS; + + ret = platform_get_tpm2_device(&dev); + if (ret != EFI_SUCCESS) + return ret; + + ret = tcg2_measure_boot_variable(dev); + if (ret != EFI_SUCCESS) + goto out; + + ret = tcg2_measure_event(dev, 4, EV_EFI_ACTION, + strlen(EFI_CALLING_EFI_APPLICATION), + (u8 *)EFI_CALLING_EFI_APPLICATION); + if (ret != EFI_SUCCESS) + goto out; + + for (pcr_index = 0; pcr_index <= 7; pcr_index++) { + ret = tcg2_measure_event(dev, pcr_index, EV_SEPARATOR, + sizeof(event), (u8 *)&event); + if (ret != EFI_SUCCESS) + goto out; + } + + tcg2_efi_app_invoked = true; +out: + return ret; +} + +/** + * efi_tcg2_measure_efi_app_exit() - measure efi app exit + * + * Return: status code + */ +efi_status_t efi_tcg2_measure_efi_app_exit(void) +{ + efi_status_t ret; + struct udevice *dev; + + ret = platform_get_tpm2_device(&dev); + if (ret != EFI_SUCCESS) + return ret; + + ret = tcg2_measure_event(dev, 4, EV_EFI_ACTION, + strlen(EFI_RETURNING_FROM_EFI_APPLICATION), + (u8 *)EFI_RETURNING_FROM_EFI_APPLICATION); + return ret; +} + /** * tcg2_measure_secure_boot_variable() - measure secure boot variables *