[RESEND,v7,00/17] Hardware wrapped key support for QCom ICE and UFS core

Message

Bartosz Golaszewski Dec. 2, 2024, 12:02 p.m. UTC

The previous iteration[1] has been on the list for many weeks without
receiving any comments - neither positive nor negative. If there are no
objections - could we start discussing how to make these patches go
upstream for v6.14?

--

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

[1] https://lore.kernel.org/all/[e-mail]/

Signed-off-by: Bartosz Golaszewski <[e-mail]>
---
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/[e-mail]

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: f486c8aa16b8172f63bddc70116a0c897a7f3f02
change-id: 20241128-wrapped-keys-c7a280792075

Best regards,

Comments

Eric Biggers Dec. 2, 2024, 6:36 p.m. UTC | #1

On Mon, Dec 02, 2024 at 01:02:16PM +0100, Bartosz Golaszewski wrote:
> The previous iteration[1] has been on the list for many weeks without
> receiving any comments - neither positive nor negative. If there are no
> objections - could we start discussing how to make these patches go
> upstream for v6.14?

The way to do it will be for the block patches to be taken through the block
tree first.  That will unblock the rest, which can be taken through their
respective trees in subsequent cycles.

I'm really hoping to be able to test these patches with upstream myself, which
I'm not able to do yet.  I'll try to leave some review comments on the parts not
authored by me the mean time.  Anyway, thanks for continuing to work on this.

> 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

That doesn't verify that the encryption is being done correctly, which is the
most important thing to test.  For that we'll need to resurrect the following
patchset for xfstests:
https://lore.kernel.org/fstests/[e-mail]/

- Eric