The preferred solution to the HWKM configuration issue seems to be using a module param so this is what I did in this iteration. Hardware-wrapped keys are encrypted keys that can only be unwrapped (decrypted) and used by hardware - either by the inline encryption hardware itself, or by a dedicated hardware block that can directly provision keys to the inline encryption hardware. For more details, please see patches 1-3 in this series which extend the inline encryption docs with more information. This series adds support for wrapped keys to the block layer, fscrypt and then build upwards from there by implementing relevant callbacks in QCom SCM driver, then the ICE driver and finally in UFS core and QCom layer. Tested on sm8650-qrd. How to test: Use the wip-wrapped-keys branch from https://github.com/ebiggers/fscryptctl to build a custom fscryptctl that supports generating wrapped keys. Enable the following config options: CONFIG_BLK_INLINE_ENCRYPTION=y CONFIG_QCOM_INLINE_CRYPTO_ENGINE=m CONFIG_FS_ENCRYPTION_INLINE_CRYPT=y CONFIG_SCSI_UFS_CRYPTO=y $ mkfs.ext4 -F -O encrypt,stable_inodes /dev/disk/by-partlabel/userdata $ mount /dev/disk/by-partlabel/userdata -o inlinecrypt /mnt $ fscryptctl generate_hw_wrapped_key /dev/disk/by-partlabel/userdata > /mnt/key.longterm $ fscryptctl prepare_hw_wrapped_key /dev/disk/by-partlabel/userdata < /mnt/key.longterm > /tmp/key.ephemeral $ KEYID=$(fscryptctl add_key --hw-wrapped-key < /tmp/key.ephemeral /mnt) $ rm -rf /mnt/dir $ mkdir /mnt/dir $ fscryptctl set_policy --hw-wrapped-key --iv-ino-lblk-64 "$KEYID" /mnt/dir $ dmesg > /mnt/dir/test.txt $ sync Reboot the board $ mount /dev/disk/by-partlabel/userdata -o inlinecrypt /mnt $ ls /mnt/dir $ fscryptctl prepare_hw_wrapped_key /dev/disk/by-partlabel/userdata < /mnt/key.longterm > /tmp/key.ephemeral $ KEYID=$(fscryptctl add_key --hw-wrapped-key < /tmp/key.ephemeral /mnt) $ fscryptctl set_policy --hw-wrapped-key --iv-ino-lblk-64 "$KEYID" /mnt/dir $ cat /mnt/dir/test.txt # File should now be decrypted Signed-off-by: Bartosz Golaszewski <bartosz.golaszewski@xxxxxxxxxx> --- Changes in v7: - use a module param in conjunction with checking the platform support at run-time to determine whether to use wrapped keys in the ICE driver - various minor refactorings, replacing magic numbers with defines etc. - fix kernel doc issues raised by autobuilders - Link to v6: https://lore.kernel.org/r/20240906-wrapped-keys-v6-0-d59e61bc0cb4@xxxxxxxxxx Changes in v6: - add the wrapped key support from Eric Biggers to the series - remove the new DT property from the series and instead query the at run-time rustZone to find out if wrapped keys are supported - make the wrapped key support into a UFS capability, not a quirk - improve kerneldocs - improve and rework coding style in most patches - improve and reformat commit messages - simplify the offset calculation for CRYPTOCFG - split out the DTS changes into a separate series --- Bartosz Golaszewski (1): firmware: qcom: scm: add a call for checking wrapped key support Eric Biggers (4): blk-crypto: add basic hardware-wrapped key support blk-crypto: show supported key types in sysfs blk-crypto: add ioctls to create and prepare hardware-wrapped keys fscrypt: add support for hardware-wrapped keys Gaurav Kashyap (12): ice, ufs, mmc: use the blk_crypto_key struct when programming the key firmware: qcom: scm: add a call for deriving the software secret firmware: qcom: scm: add calls for creating, preparing and importing keys soc: qcom: ice: add HWKM support to the ICE driver soc: qcom: ice: add support for hardware wrapped keys soc: qcom: ice: add support for generating, importing and preparing keys ufs: core: add support for wrapped keys to UFS core ufs: core: add support for deriving the software secret ufs: core: add support for generating, importing and preparing keys ufs: host: add support for wrapped keys in QCom UFS ufs: host: add a callback for deriving software secrets and use it ufs: host: add support for generating, importing and preparing wrapped keys Documentation/ABI/stable/sysfs-block | 18 + Documentation/block/inline-encryption.rst | 245 +++++++++++++- Documentation/filesystems/fscrypt.rst | 154 ++++++++- Documentation/userspace-api/ioctl/ioctl-number.rst | 2 + block/blk-crypto-fallback.c | 5 +- block/blk-crypto-internal.h | 10 + block/blk-crypto-profile.c | 103 ++++++ block/blk-crypto-sysfs.c | 35 ++ block/blk-crypto.c | 194 ++++++++++- block/ioctl.c | 5 + drivers/firmware/qcom/qcom_scm.c | 233 +++++++++++++ drivers/firmware/qcom/qcom_scm.h | 4 + drivers/md/dm-table.c | 1 + drivers/mmc/host/cqhci-crypto.c | 9 +- drivers/mmc/host/cqhci.h | 2 + drivers/mmc/host/sdhci-msm.c | 6 +- drivers/soc/qcom/ice.c | 365 ++++++++++++++++++++- drivers/ufs/core/ufshcd-crypto.c | 86 ++++- drivers/ufs/host/ufs-qcom.c | 61 +++- fs/crypto/fscrypt_private.h | 71 +++- fs/crypto/hkdf.c | 4 +- fs/crypto/inline_crypt.c | 44 ++- fs/crypto/keyring.c | 124 +++++-- fs/crypto/keysetup.c | 54 ++- fs/crypto/keysetup_v1.c | 5 +- fs/crypto/policy.c | 11 +- include/linux/blk-crypto-profile.h | 73 +++++ include/linux/blk-crypto.h | 75 ++++- include/linux/firmware/qcom/qcom_scm.h | 8 + include/soc/qcom/ice.h | 18 +- include/uapi/linux/blk-crypto.h | 44 +++ include/uapi/linux/fs.h | 6 +- include/uapi/linux/fscrypt.h | 7 +- include/ufs/ufshcd.h | 21 ++ 34 files changed, 1968 insertions(+), 135 deletions(-) --- base-commit: eae80d86fb04e37032e5bdaec64e0b70316d11ae change-id: 20240802-wrapped-keys-eea0032fbfed Best regards, -- Bartosz Golaszewski <bartosz.golaszewski@xxxxxxxxxx>