Re: [PATCH v2 0/3] fscrypt: support for IV_INO_LBLK_64 policies

[Eric Biggers <ebiggers@kernel.org>]

On Thu, Oct 24, 2019 at 02:54:35PM -0700, Eric Biggers wrote:
> Hello,
> 
> In preparation for adding inline encryption support to fscrypt, this
> patchset adds a new fscrypt policy flag which modifies the encryption to
> be optimized for inline encryption hardware compliant with the UFS v2.1
> standard or the upcoming version of the eMMC standard.
> 
> This means using per-mode keys instead of per-file keys, and in
> compensation including the inode number in the IVs.  For ext4, this
> precludes filesystem shrinking, so I've also added a compat feature
> which will prevent the filesystem from being shrunk.
> 
> I've separated this from the full "Inline Encryption Support" patchset
> (https://lkml.kernel.org/linux-fsdevel/20190821075714.65140-1-satyat@google.com/)
> to avoid conflating an implementation (inline encryption) with a new
> on-disk format (IV_INO_LBLK_64).  This patchset purely adds support for
> IV_INO_LBLK_64 policies to fscrypt, but implements them using the
> existing filesystem layer crypto.
> 
> We're planning to make the *implementation* (filesystem layer or inline
> crypto) be controlled by a mount option '-o inlinecrypt'.
> 
> This patchset applies to fscrypt.git#master and can also be retrieved from
> https://git.kernel.org/pub/scm/linux/kernel/git/ebiggers/linux.git/log/?h=inline-crypt-optimized-v2
> 
> I've written a ciphertext verification test for this new type of policy:
> https://git.kernel.org/pub/scm/linux/kernel/git/ebiggers/xfstests-dev.git/log/?h=inline-encryption
> 
> Work-in-progress patches for the inline encryption implementation of
> both IV_INO_LBLK_64 and regular policies can be found at
> https://git.kernel.org/pub/scm/linux/kernel/git/ebiggers/linux.git/log/?h=inline-encryption-wip
> 
> Changes v1 => v2:
> 
> - Rename the flag from INLINE_CRYPT_OPTIMIZED to IV_INO_LBLK_64.
> 
> - Use the same key derivation and IV generation scheme for filenames
>   encryption too.
> 
> - Improve the documentation and commit messages.
> 
> Eric Biggers (3):
>   fscrypt: add support for IV_INO_LBLK_64 policies
>   ext4: add support for IV_INO_LBLK_64 encryption policies
>   f2fs: add support for IV_INO_LBLK_64 encryption policies
> 

Does anyone have any more comments on these patches?

- Eric