Re: [PATCH 7/8] hw/sd/sdcard: Handle RPMB MAC field

["Philippe Mathieu-Daudé" <philmd@linaro.org>]

Hi Jan,

On 24/8/25 09:18, Jan Kiszka wrote:
> From: Jan Kiszka <jan.kiszka@siemens.com>
> 
> Implement correct setting of the MAC field when passing RPMB frames back
> to the guest. Also check the MAC on authenticated write requests.
> 
> As this depends on HMAC support for QCRYPTO_HASH_ALGO_SHA256, only
> register the eMMC class if that is available.
> 
> Signed-off-by: Jan Kiszka <jan.kiszka@siemens.com>
> ---
>   hw/sd/sd.c | 90 +++++++++++++++++++++++++++++++++++++++++++++++++++++-
>   1 file changed, 89 insertions(+), 1 deletion(-)


> @@ -3122,6 +3201,7 @@ static const TypeInfo sd_types[] = {
>           .parent         = TYPE_SD_CARD,
>           .class_init     = sd_spi_class_init,
>       },
> +    /* must be last element */
>       {
>           .name           = TYPE_EMMC,
>           .parent         = TYPE_SDMMC_COMMON,
> @@ -3129,4 +3209,12 @@ static const TypeInfo sd_types[] = {
>       },
>   };
>   
> -DEFINE_TYPES(sd_types)
> +static void sd_register_types(void)
> +{
> +    int num = ARRAY_SIZE(sd_types);
> +    if (!qcrypto_hmac_supports(QCRYPTO_HASH_ALGO_SHA256)) {
> +        num--;

Instead, expose RPMB feature in CSD when HMAC supported?

Something in emmc_set_ext_csd() in the lines of:

   if (qcrypto_hmac_supports(QCRYPTO_HASH_ALGO_SHA256)) {
       sd->ext_csd[EXT_CSD_REV] = 5;
       sd->ext_csd[EXT_CSD_RPMB_MULT] = sd->rpmb_part_size / (128 * KiB);
       sd->ext_csd[EXT_CSD_PARTITION_SUPPORT] = 0b111;
   } else {
       sd->ext_csd[EXT_CSD_REV] = 3;
   }

> +    }
> +    type_register_static_array(sd_types, num);
> +}
> +type_init(sd_register_types);