[PATCH v2 2/4] efi_loader: versioning support in GetImageInfo

[Takahiro Akashi]

On Wed, Mar 01, 2023 at 06:15:20PM +0900, Masahisa Kojima wrote:
> Current FMP->GetImageInfo() always return 0 for the firmware
> version, user can not identify which firmware version is currently
> running through the EFI interface.
> 
> This commit reads the "FmpStateXXXX" EFI variable, then fills the
> firmware version, lowest supported version, last attempt version
> and last attempt status in FMP->GetImageInfo().
> 
> Now FMP->GetImageInfo() and ESRT have the meaningful version number.
> 
> Signed-off-by: Masahisa Kojima <masahisa.kojima at linaro.org>
> ---
> No update since v1
> 
>  lib/efi_loader/efi_firmware.c | 30 ++++++++++++++++++++++++++----
>  1 file changed, 26 insertions(+), 4 deletions(-)
> 
> diff --git a/lib/efi_loader/efi_firmware.c b/lib/efi_loader/efi_firmware.c
> index d1afafb052..ead20fa914 100644
> --- a/lib/efi_loader/efi_firmware.c
> +++ b/lib/efi_loader/efi_firmware.c
> @@ -173,13 +173,38 @@ static efi_status_t efi_fill_image_desc_array(
>  	*package_version_name = NULL; /* not supported */
>  
>  	for (i = 0; i < num_image_type_guids; i++) {
> +		u16 varname[13]; /* u"FmpStateXXXX" */
> +		efi_status_t ret;
> +		efi_uintn_t size;
> +		struct fmp_state var_state = { 0 };
> +
>  		image_info[i].image_index = fw_array[i].image_index;
>  		image_info[i].image_type_id = fw_array[i].image_type_id;
>  		image_info[i].image_id = fw_array[i].image_index;
>  
>  		image_info[i].image_id_name = fw_array[i].fw_name;
>  
> -		image_info[i].version = 0; /* not supported */
> +		efi_create_indexed_name(varname, sizeof(varname), "FmpState",
> +					fw_array[i].image_index);

Don't we have to think of the systems where multiple FMP drivers are
used? In those cases, 'image_index' doesn't work as an unique ID.
It is unlikely under the current code, but we should consider
any future extension.

-Takahiro Akashi


> +		size = sizeof(var_state);
> +		ret = efi_get_variable_int(varname, &efi_guid_fmp_state, NULL,
> +					   &size, &var_state, NULL);
> +		if (ret == EFI_SUCCESS) {
> +			image_info[i].version = var_state.fw_version;
> +			image_info[i].lowest_supported_image_version =
> +				var_state.lowest_supported_version;
> +			image_info[i].last_attempt_version =
> +				var_state.last_attempt_version;
> +			image_info[i].last_attempt_status =
> +				var_state.last_attempt_status;
> +		} else {
> +			image_info[i].version = 0;
> +			image_info[i].lowest_supported_image_version = 0;
> +			image_info[i].last_attempt_version = 0;
> +			image_info[i].last_attempt_status =
> +				LAST_ATTEMPT_STATUS_SUCCESS;
> +		}
> +
>  		image_info[i].version_name = NULL; /* not supported */
>  		image_info[i].size = 0;
>  		image_info[i].attributes_supported =
> @@ -193,9 +218,6 @@ static efi_status_t efi_fill_image_desc_array(
>  			image_info[0].attributes_setting |=
>  				IMAGE_ATTRIBUTE_AUTHENTICATION_REQUIRED;
>  
> -		image_info[i].lowest_supported_image_version = 0;
> -		image_info[i].last_attempt_version = 0;
> -		image_info[i].last_attempt_status = LAST_ATTEMPT_STATUS_SUCCESS;
>  		image_info[i].hardware_instance = 1;
>  		image_info[i].dependencies = NULL;
>  	}
> -- 
> 2.17.1
>