diff options
| -rw-r--r-- | cmd/eficonfig_sbkey.c | 38 |
1 files changed, 36 insertions, 2 deletions
diff --git a/cmd/eficonfig_sbkey.c b/cmd/eficonfig_sbkey.c index 6e0bebf1d41..ed39aab0817 100644 --- a/cmd/eficonfig_sbkey.c +++ b/cmd/eficonfig_sbkey.c @@ -73,6 +73,28 @@ static bool file_have_auth_header(void *buf, efi_uintn_t size) } /** + * file_is_null_key() - check the file is an authenticated and signed null key + * + * @auth: pointer to the file + * @size: file size + * @null_key: pointer to store the result + * Return: status code + */ +static efi_status_t file_is_null_key(struct efi_variable_authentication_2 *auth, + efi_uintn_t size, bool *null_key) +{ + efi_uintn_t auth_size = + sizeof(auth->time_stamp) + auth->auth_info.hdr.dwLength; + + if (size < auth_size) + return EFI_INVALID_PARAMETER; + + *null_key = (size == auth_size); + + return EFI_SUCCESS; +} + +/** * eficonfig_process_enroll_key() - enroll key into signature database * * @data: pointer to the data for each entry @@ -84,6 +106,7 @@ static efi_status_t eficonfig_process_enroll_key(void *data) char *buf = NULL; efi_uintn_t size; efi_status_t ret; + bool null_key = false; struct efi_file_handle *f = NULL; struct efi_device_path *full_dp = NULL; struct eficonfig_select_file_info file_info; @@ -149,13 +172,24 @@ static efi_status_t eficonfig_process_enroll_key(void *data) goto out; } + ret = file_is_null_key((struct efi_variable_authentication_2 *)buf, + size, &null_key); + if (ret != EFI_SUCCESS) { + eficonfig_print_msg("ERROR! Invalid file format."); + goto out; + } + attr = EFI_VARIABLE_NON_VOLATILE | EFI_VARIABLE_BOOTSERVICE_ACCESS | EFI_VARIABLE_RUNTIME_ACCESS | EFI_VARIABLE_TIME_BASED_AUTHENTICATED_WRITE_ACCESS; - /* PK can enroll only one certificate */ - if (u16_strcmp(data, u"PK")) { + /* + * PK can enroll only one certificate. + * The signed null key is used to clear KEK, db and dbx. + * EFI_VARIABLE_APPEND_WRITE attribute must not be set in these cases. + */ + if (u16_strcmp(data, u"PK") && !null_key) { efi_uintn_t db_size = 0; /* check the variable exists. If exists, add APPEND_WRITE attribute */ |