This commit modify efi_tcg2_register() to return the appropriate error. With this fix, sandbox will not boot because efi_tcg2_register() fails due to some missing feature in GetCapabilities. So disable sandbox if EFI_TCG2_PROTOCOL is enabled.
UEFI secure boot variable measurement is not directly related to TCG2 protocol installation, tcg2_measure_secure_boot_variable() is moved to the separate function.
Signed-off-by: Masahisa Kojima masahisa.kojima@linaro.org --- include/efi_loader.h | 2 ++ lib/efi_loader/Kconfig | 2 ++ lib/efi_loader/efi_setup.c | 2 ++ lib/efi_loader/efi_tcg2.c | 65 +++++++++++++++++++++++++++----------- 4 files changed, 53 insertions(+), 18 deletions(-)
diff --git a/include/efi_loader.h b/include/efi_loader.h index 67c40ca57a..f4860e87fc 100644 --- a/include/efi_loader.h +++ b/include/efi_loader.h @@ -525,6 +525,8 @@ 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 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/Kconfig b/lib/efi_loader/Kconfig index 700dc838dd..24f9a2bb75 100644 --- a/lib/efi_loader/Kconfig +++ b/lib/efi_loader/Kconfig @@ -308,6 +308,8 @@ config EFI_TCG2_PROTOCOL bool "EFI_TCG2_PROTOCOL support" default y depends on TPM_V2 + # Sandbox TPM currently fails on GetCapabilities needed for TCG2 + depends on !SANDBOX select SHA1 select SHA256 select SHA384 diff --git a/lib/efi_loader/efi_setup.c b/lib/efi_loader/efi_setup.c index 1aba71cd96..f58a4afa7f 100644 --- a/lib/efi_loader/efi_setup.c +++ b/lib/efi_loader/efi_setup.c @@ -241,6 +241,8 @@ efi_status_t efi_init_obj_list(void) ret = efi_tcg2_register(); if (ret != EFI_SUCCESS) goto out; + + efi_tcg2_do_initial_measurement(); }
/* Secure boot */ diff --git a/lib/efi_loader/efi_tcg2.c b/lib/efi_loader/efi_tcg2.c index 5f71b188a0..6dbdd35f29 100644 --- a/lib/efi_loader/efi_tcg2.c +++ b/lib/efi_loader/efi_tcg2.c @@ -153,6 +153,15 @@ static u16 alg_to_len(u16 hash_alg) return 0; }
+static 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; +} + static u32 tcg_event_final_size(struct tpml_digest_values *digest_list) { u32 len; @@ -1664,6 +1673,14 @@ void tcg2_uninit(void) event_log.buffer = NULL; efi_free_pool(event_log.final_buffer); event_log.final_buffer = NULL; + + if (!is_tcg2_protocol_installed()) + return; + + ret = efi_remove_protocol(efi_root, &efi_guid_tcg2_protocol, + (void *)&efi_tcg2_protocol); + if (ret != EFI_SUCCESS) + log_err("Failed to remove EFI TCG2 protocol\n"); }
/** @@ -2345,12 +2362,37 @@ error: 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; + + if (!is_tcg2_protocol_installed()) + return EFI_SUCCESS; + + 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 * * If a TPM2 device is available, the TPM TCG2 Protocol is registered * - * Return: An error status is only returned if adding the protocol fails. + * Return: status code */ efi_status_t efi_tcg2_register(void) { @@ -2373,8 +2415,10 @@ efi_status_t efi_tcg2_register(void) }
ret = efi_init_event_log(); - if (ret != EFI_SUCCESS) + if (ret != EFI_SUCCESS) { + tcg2_uninit(); goto fail; + }
ret = efi_add_protocol(efi_root, &efi_guid_tcg2_protocol, (void *)&efi_tcg2_protocol); @@ -2391,24 +2435,9 @@ efi_status_t efi_tcg2_register(void) goto fail; }
- ret = tcg2_measure_secure_boot_variable(dev); - if (ret != EFI_SUCCESS) { - tcg2_uninit(); - goto fail; - } - return ret;
fail: log_err("Cannot install EFI_TCG2_PROTOCOL\n"); - /* - * Return EFI_SUCCESS and don't stop the EFI subsystem. - * That's done for 2 reasons - * - If the protocol is not installed the PCRs won't be extended. So - * someone later in the boot flow will notice that and take the - * necessary actions. - * - The TPM sandbox is limited and we won't be able to run any efi - * related tests with TCG2 enabled - */ - return EFI_SUCCESS; + return ret; }