There are functions that calls tcg2_agile_log_append() outside of the TCG protocol invocation (e.g tcg2_measure_pe_image). These functions must to check that tcg2 protocol is installed. If not, measurement shall be skipped.

Together with above change, this commit also removes the unnecessary tcg2_uninit() call in efi_tcg2_register(), refactors efi_tcg2_register() not to include the process that is not related to the tcg2 protocol registration.

Signed-off-by: Masahisa Kojima masahisa.kojima@linaro.org --- Changes in v2: - rebased on top of the TF-A eventlog handover support

include/efi_loader.h | 4 ++ lib/efi_loader/efi_setup.c | 3 ++ lib/efi_loader/efi_tcg2.c | 89 +++++++++++++++++++++++++++++++------- 3 files changed, 81 insertions(+), 15 deletions(-)

diff --git a/include/efi_loader.h b/include/efi_loader.h index d52e399841..fe29c10906 100644 --- a/include/efi_loader.h +++ b/include/efi_loader.h @@ -525,6 +525,10 @@ efi_status_t efi_disk_register(void); efi_status_t efi_rng_register(void); /* Called by efi_init_obj_list() to install EFI_TCG2_PROTOCOL */ efi_status_t efi_tcg2_register(void); +/* Called by efi_init_obj_list() to do the required setup for the measurement */ +efi_status_t efi_tcg2_setup_measurement(void); +/* Called by efi_init_obj_list() to do initial measurement */ +efi_status_t efi_tcg2_do_initial_measurement(void); /* measure the pe-coff image, extend PCR and add Event Log */ efi_status_t tcg2_measure_pe_image(void *efi, u64 efi_size, struct efi_loaded_image_obj *handle, diff --git a/lib/efi_loader/efi_setup.c b/lib/efi_loader/efi_setup.c index a2338d74af..781d10590d 100644 --- a/lib/efi_loader/efi_setup.c +++ b/lib/efi_loader/efi_setup.c @@ -271,6 +271,9 @@ efi_status_t efi_init_obj_list(void) ret = efi_tcg2_register(); if (ret != EFI_SUCCESS) goto out; + + efi_tcg2_setup_measurement(); + efi_tcg2_do_initial_measurement(); }

/* Secure boot */ diff --git a/lib/efi_loader/efi_tcg2.c b/lib/efi_loader/efi_tcg2.c index b44eed0ec9..0a33f5ab5f 100644 --- a/lib/efi_loader/efi_tcg2.c +++ b/lib/efi_loader/efi_tcg2.c @@ -153,6 +153,20 @@ static u16 alg_to_len(u16 hash_alg) return 0; }

+/** + * is_tcg2_protocol_installed - chech whether tcg2 protocol is installed + * + * @Return: true if tcg2 protocol is installed, false if not + */ +bool is_tcg2_protocol_installed(void) +{ + struct efi_handler *handler; + efi_status_t ret; + + ret = efi_search_protocol(efi_root, &efi_guid_tcg2_protocol, &handler); + return ((ret == EFI_SUCCESS) ? true : false); +} + static u32 tcg_event_final_size(struct tpml_digest_values *digest_list) { u32 len; @@ -962,6 +976,9 @@ efi_status_t tcg2_measure_pe_image(void *efi, u64 efi_size, IMAGE_NT_HEADERS32 *nt; struct efi_handler *handler;

+ if (!is_tcg2_protocol_installed()) + return EFI_NOT_READY; + ret = platform_get_tpm2_device(&dev); if (ret != EFI_SUCCESS) return ret; @@ -2140,6 +2157,9 @@ efi_status_t efi_tcg2_measure_efi_app_invocation(struct efi_loaded_image_obj *ha u32 event = 0; struct smbios_entry *entry;

+ if (!is_tcg2_protocol_installed()) + return EFI_NOT_READY; + if (tcg2_efi_app_invoked) return EFI_SUCCESS;

@@ -2190,6 +2210,9 @@ efi_status_t efi_tcg2_measure_efi_app_exit(void) efi_status_t ret; struct udevice *dev;

+ if (!is_tcg2_protocol_installed()) + return EFI_NOT_READY; + ret = platform_get_tpm2_device(&dev); if (ret != EFI_SUCCESS) return ret; @@ -2214,6 +2237,11 @@ efi_tcg2_notify_exit_boot_services(struct efi_event *event, void *context)

EFI_ENTRY("%p, %p", event, context);

+ if (!is_tcg2_protocol_installed()) { + ret = EFI_NOT_READY; + goto out; + } + event_log.ebs_called = true; ret = platform_get_tpm2_device(&dev); if (ret != EFI_SUCCESS) @@ -2244,6 +2272,9 @@ efi_status_t efi_tcg2_notify_exit_boot_services_failed(void) struct udevice *dev; efi_status_t ret;

+ if (!is_tcg2_protocol_installed()) + return EFI_NOT_READY; + ret = platform_get_tpm2_device(&dev); if (ret != EFI_SUCCESS) goto out; @@ -2313,6 +2344,45 @@ error: return ret; }

+/** + * efi_tcg2_setup_measurement() - setup for the measurement + * + * Return: status code + */ +efi_status_t efi_tcg2_setup_measurement(void) +{ + efi_status_t ret; + struct efi_event *event; + + ret = efi_create_event(EVT_SIGNAL_EXIT_BOOT_SERVICES, TPL_CALLBACK, + efi_tcg2_notify_exit_boot_services, NULL, + NULL, &event); + + return ret; +} + +/** + * efi_tcg2_do_initial_measurement() - do initial measurement + * + * Return: status code + */ +efi_status_t efi_tcg2_do_initial_measurement(void) +{ + efi_status_t ret; + struct udevice *dev; + + ret = platform_get_tpm2_device(&dev); + if (ret != EFI_SUCCESS) + goto out; + + ret = tcg2_measure_secure_boot_variable(dev); + if (ret != EFI_SUCCESS) + goto out; + +out: + return ret; +} + /** * efi_tcg2_register() - register EFI_TCG2_PROTOCOL * @@ -2324,7 +2394,6 @@ efi_status_t efi_tcg2_register(void) { efi_status_t ret = EFI_SUCCESS; struct udevice *dev; - struct efi_event *event; u32 err;

ret = platform_get_tpm2_device(&dev); @@ -2344,6 +2413,10 @@ efi_status_t efi_tcg2_register(void) if (ret != EFI_SUCCESS) goto fail;

+ /* + * efi_add_protocol() is called at last on purpose. + * tcg2_uninit() does not uninstall the tcg2 protocol, but it is intended. + */ ret = efi_add_protocol(efi_root, &efi_guid_tcg2_protocol, (void *)&efi_tcg2_protocol); if (ret != EFI_SUCCESS) { @@ -2351,20 +2424,6 @@ efi_status_t efi_tcg2_register(void) goto fail; }

- ret = efi_create_event(EVT_SIGNAL_EXIT_BOOT_SERVICES, TPL_CALLBACK, - efi_tcg2_notify_exit_boot_services, NULL, - NULL, &event); - if (ret != EFI_SUCCESS) { - tcg2_uninit(); - goto fail; - } - - ret = tcg2_measure_secure_boot_variable(dev); - if (ret != EFI_SUCCESS) { - tcg2_uninit(); - goto fail; - } - return ret;

fail: