Re: [PATCH v4 08/15] ufs: core: add support to derive software secret

Om Prakash Singh
2024-02-05T18:52:36Z

On 1/28/2024 4:44 AM, Gaurav Kashyap wrote:
> Block crypto allows storage controllers like UFS to
> register an op derive a software secret from wrapped
> keys added to the kernel.
>
> Wrapped keys in most cases will have vendor specific
> implementations, which means this op would need to have
> a corresponding UFS variant op.
> This change adds hooks in UFS core to support this variant
> ops and tie them to the blk crypto op.
>
> Signed-off-by: Gaurav Kashyap <quic_gaurkash@quicinc.com>
> Tested-by: Neil Armstrong <neil.armstrong@linaro.org>
> ---
Reviewed-by: Om Prakash Singh <quic_omprsing@quicinc.com>

> drivers/ufs/core/ufshcd-crypto.c | 15 +++++++++++++++
> include/ufs/ufshcd.h | 4 ++++
> 2 files changed, 19 insertions(+)
>
> diff --git a/drivers/ufs/core/ufshcd-crypto.c b/drivers/ufs/core/ufshcd-crypto.c
> index 399b55d67b3b..c14800eac1ff 100644
> --- a/drivers/ufs/core/ufshcd-crypto.c
> +++ b/drivers/ufs/core/ufshcd-crypto.c
> @@ -119,6 +119,20 @@ static int ufshcd_crypto_keyslot_evict(struct blk_crypto_profile *profile,
> return ufshcd_clear_keyslot(hba, slot);
> }
>
> +static int ufshcd_crypto_derive_sw_secret(struct blk_crypto_profile *profile,
> + const u8 wkey[], size_t wkey_size,
> + u8 sw_secret[BLK_CRYPTO_SW_SECRET_SIZE])
> +{
> + struct ufs_hba *hba =
> + container_of(profile, struct ufs_hba, crypto_profile);
> +
> + if (hba->vops && hba->vops->derive_sw_secret)
> + return hba->vops->derive_sw_secret(hba, wkey, wkey_size,
> + sw_secret);
> +
> + return -EOPNOTSUPP;
> +}
> +
> bool ufshcd_crypto_enable(struct ufs_hba *hba)
> {
> if (!(hba->caps & UFSHCD_CAP_CRYPTO))
> @@ -132,6 +146,7 @@ bool ufshcd_crypto_enable(struct ufs_hba *hba)
> static const struct blk_crypto_ll_ops ufshcd_crypto_ops = {
> .keyslot_program = ufshcd_crypto_keyslot_program,
> .keyslot_evict = ufshcd_crypto_keyslot_evict,
> + .derive_sw_secret = ufshcd_crypto_derive_sw_secret,
> };
>
> static enum blk_crypto_mode_num
> diff --git a/include/ufs/ufshcd.h b/include/ufs/ufshcd.h
> index 680c010a53d4..8a773434a329 100644
> --- a/include/ufs/ufshcd.h
> +++ b/include/ufs/ufshcd.h
> @@ -321,6 +321,7 @@ struct ufs_pwr_mode_info {
> * @device_reset: called to issue a reset pulse on the UFS device
> * @config_scaling_param: called to configure clock scaling parameters
> * @program_key: program or evict an inline encryption key
> + * @derive_sw_secret: derive sw secret from a wrapped key
> * @event_notify: called to notify important events
> * @reinit_notify: called to notify reinit of UFSHCD during max gear switch
> * @mcq_config_resource: called to configure MCQ platform resources
> @@ -365,6 +366,9 @@ struct ufs_hba_variant_ops {
> int (*program_key)(struct ufs_hba *hba,
> const struct blk_crypto_key *bkey,
> const union ufs_crypto_cfg_entry *cfg, int slot);
> + int (*derive_sw_secret)(struct ufs_hba *hba, const u8 wkey[],
> + unsigned int wkey_size,
> + u8 sw_secret[BLK_CRYPTO_SW_SECRET_SIZE]);
> void (*event_notify)(struct ufs_hba *hba,
> enum ufs_event_type evt, void *data);
> void (*reinit_notify)(struct ufs_hba *);