Commit Graph

9 Commits

Author SHA1 Message Date
Eric Biggers
a7ffddad1f BACKPORT: FROMLIST: fscrypt: add support for IV_INO_LBLK_32 policies
The eMMC inline crypto standard will only specify 32 DUN bits (a.k.a. IV
bits), unlike UFS's 64.  IV_INO_LBLK_64 is therefore not applicable, but
an encryption format which uses one key per policy and permits the
moving of encrypted file contents (as f2fs's garbage collector requires)
is still desirable.

To support such hardware, add a new encryption format IV_INO_LBLK_32
that makes the best use of the 32 bits: the IV is set to
'SipHash-2-4(inode_number) + file_logical_block_number mod 2^32', where
the SipHash key is derived from the fscrypt master key.  We hash only
the inode number and not also the block number, because we need to
maintain contiguity of DUNs to merge bios.

Unlike with IV_INO_LBLK_64, with this format IV reuse is possible; this
is unavoidable given the size of the DUN.  This means this format should
only be used where the requirements of the first paragraph apply.
However, the hash spreads out the IVs in the whole usable range, and the
use of a keyed hash makes it difficult for an attacker to determine
which files use which IVs.

Besides the above differences, this flag works like IV_INO_LBLK_64 in
that on ext4 it is only allowed if the stable_inodes feature has been
enabled to prevent inode numbers and the filesystem UUID from changing.

Link: https://lore.kernel.org/r/20200515204141.251098-1-ebiggers@kernel.org

(Resolved conflicts with inline encryption support.  Besides the
 necessary "straightforward" merge resolutions, also made
 fscrypt_get_dun_bytes() aware of IV_INO_LBLK_32 and made IV_INO_LBLK_32
 usable with wrapped keys.)

Test: 'atest vts_kernel_encryption_test' on Cuttlefish with
      the IV_INO_LBLK_32 test added (http://aosp/1315024).

      Also tested enabling this in the fstab for Cuttlefish
      (using http://aosp/1315886).

      Also ran 'kvm-xfstests -c ext4,f2fs -g encrypt', including my
      work-in-progress xfstest for IV_INO_LBLK_32.

Bug: 144046242
Change-Id: I57df71d502bde0475efc906a0812102063ff2f2a
Signed-off-by: Eric Biggers <ebiggers@google.com>
2020-05-30 02:32:43 +08:00
Eric Biggers
aea8050678 fscrypt, ufs-qcom: remove legacy ICE compatibility code
Remove the fscrypt and ufs-qcom hacks we added to make this kernel
branch work with unmodified Qualcomm Keystone builds, now that this is
no longer needed.

This gets fscrypt in sync with android-4.19-stable after we also
cherry-pick a missing fscrypt commit.

Bug: 147259927
Change-Id: I30517a87af84599cfbe681d37b68764a292329d1
Signed-off-by: Eric Biggers <ebiggers@google.com>
2020-05-30 02:25:08 +08:00
Eric Biggers
62d98541ca UPSTREAM: fscrypt: add FS_IOC_GET_ENCRYPTION_NONCE ioctl
Add an ioctl FS_IOC_GET_ENCRYPTION_NONCE which retrieves the nonce from
an encrypted file or directory.  The nonce is the 16-byte random value
stored in the inode's encryption xattr.  It is normally used together
with the master key to derive the inode's actual encryption key.

The nonces are needed by automated tests that verify the correctness of
the ciphertext on-disk.  Except for the IV_INO_LBLK_64 case, there's no
way to replicate a file's ciphertext without knowing that file's nonce.

The nonces aren't secret, and the existing ciphertext verification tests
in xfstests retrieve them from disk using debugfs or dump.f2fs.  But in
environments that lack these debugging tools, getting the nonces by
manually parsing the filesystem structure would be very hard.

To make this important type of testing much easier, let's just add an
ioctl that retrieves the nonce.

Link: https://lore.kernel.org/r/20200314205052.93294-2-ebiggers@kernel.org
Reviewed-by: Theodore Ts'o <tytso@mit.edu>
(cherry picked from commit e98ad464750c0894bc560d10503dae8ff90ccdac)
Bug: 151100202
Change-Id: Ieef2c57b9257ae38eb2e5c1a018ca6f325bb62dd
Signed-off-by: Eric Biggers <ebiggers@google.com>
2020-05-30 02:21:38 +08:00
Eric Biggers
ffbe922310 Merge remote-tracking branch 'aosp/upstream-f2fs-stable-linux-4.19.y' into android-4.19
* aosp/upstream-f2fs-stable-linux-4.19.y:
  fs-verity: use u64_to_user_ptr()
  fs-verity: use mempool for hash requests
  fs-verity: implement readahead of Merkle tree pages
  fs-verity: implement readahead for FS_IOC_ENABLE_VERITY
  fscrypt: improve format of no-key names
  ubifs: allow both hash and disk name to be provided in no-key names
  ubifs: don't trigger assertion on invalid no-key filename
  fscrypt: clarify what is meant by a per-file key
  fscrypt: derive dirhash key for casefolded directories
  fscrypt: don't allow v1 policies with casefolding
  fscrypt: add "fscrypt_" prefix to fname_encrypt()
  fscrypt: don't print name of busy file when removing key
  fscrypt: document gfp_flags for bounce page allocation
  fscrypt: optimize fscrypt_zeroout_range()
  fscrypt: remove redundant bi_status check
  fscrypt: Allow modular crypto algorithms
  fscrypt: include <linux/ioctl.h> in UAPI header
  fscrypt: don't check for ENOKEY from fscrypt_get_encryption_info()
  fscrypt: remove fscrypt_is_direct_key_policy()
  fscrypt: move fscrypt_valid_enc_modes() to policy.c
  fscrypt: check for appropriate use of DIRECT_KEY flag earlier
  fscrypt: split up fscrypt_supported_policy() by policy version
  fscrypt: introduce fscrypt_needs_contents_encryption()
  fscrypt: move fscrypt_d_revalidate() to fname.c
  fscrypt: constify inode parameter to filename encryption functions
  fscrypt: constify struct fscrypt_hkdf parameter to fscrypt_hkdf_expand()
  fscrypt: verify that the crypto_skcipher has the correct ivsize
  fscrypt: use crypto_skcipher_driver_name()
  fscrypt: support passing a keyring key to FS_IOC_ADD_ENCRYPTION_KEY
  keys: Export lookup_user_key to external users

Conflicts:
        fs/crypto/Kconfig
        fs/crypto/bio.c
        fs/crypto/fname.c
        fs/crypto/fscrypt_private.h
        fs/crypto/keyring.c
        fs/crypto/keysetup.c
        fs/ubifs/dir.c
        include/uapi/linux/fscrypt.h

Resolved the conflicts as per the corresponding android-mainline change,
Ib1e6b9eda8fb5dcfc6bdc8fa89d93f72b088c5f6.

Additional conflicts when cherry-picking the merge commit to
android-msm-pixel-4.19:

    fs/crypto/fscrypt_private.h
    fs/crypto/policy.c
    => Resolved by moving the LEGACY_ICE handling code.

    fs/ubifs/dir.c
    => Resolved by adding the change from 4.19-stable patch
       "ubifs: don't trigger assertion on invalid no-key filename"

Bug: 148667616
Change-Id: I5f8b846f0cd4d5403d8c61b9e12acb4581fac6f7
Signed-off-by: Eric Biggers <ebiggers@google.com>
2020-05-30 02:15:29 +08:00
Barani Muthukumaran
8079b400ce ANDROID: fscrypt: add support for hardware-wrapped keys
To prevent keys from being compromised if an attacker acquires read
access to kernel memory, some inline encryption hardware supports
protecting the keys in hardware without software having access to or the
ability to set the plaintext keys.  Instead, software only sees "wrapped
keys", which may differ on every boot.  The keys can be initially
generated either by software (in which case they need to be imported to
hardware to be wrapped), or directly by the hardware.

Add support for this type of hardware by allowing keys to be flagged as
hardware-wrapped and encryption policies to be flagged as needing a
hardware-wrapped key.  When used, fscrypt will pass the wrapped key
directly to the inline encryption hardware to encrypt file contents.
The hardware is responsible for internally unwrapping the key and
deriving the actual file contents encryption key.

fscrypt also asks the inline encryption hardware to derive a
cryptographically isolated software "secret", which fscrypt then uses as
the master key for all other purposes besides file contents encryption,
e.g. to derive filenames encryption keys and the key identifier.

Bug: 147209885

Change-Id: I7f4cc5c32f130709db3eb9ebdb1ebfff5751ca95
Co-developed-by: Gaurav Kashyap <gaurkash@codeaurora.org>
Signed-off-by: Gaurav Kashyap <gaurkash@codeaurora.org>
Signed-off-by: Barani Muthukumaran <bmuthuku@codeaurora.org>
Signed-off-by: Eric Biggers <ebiggers@google.com>
2020-05-30 02:15:28 +08:00
Eric Biggers
cd53d06499 [TEMPORARY] fscrypt: support legacy ICE mode
Temporarily add back support for the legacy fileencryption=ice, i.e. v1
fscrypt policies with contents encryption mode 127.

This commit should be reverted once all needed fstabs have been updated.

Bug: 147259927
Change-Id: I74e8a1fb863973bf196142e2411e8ea21a6a8fc0
Signed-off-by: Eric Biggers <ebiggers@google.com>
2020-05-30 02:04:35 +08:00
Eric Biggers
b335ab87da BACKPORT: FROMLIST: fscrypt: add support for IV_INO_LBLK_64 policies
Inline encryption hardware compliant with the UFS v2.1 standard or with
the upcoming version of the eMMC standard has the following properties:

(1) Per I/O request, the encryption key is specified by a previously
    loaded keyslot.  There might be only a small number of keyslots.

(2) Per I/O request, the starting IV is specified by a 64-bit "data unit
    number" (DUN).  IV bits 64-127 are assumed to be 0.  The hardware
    automatically increments the DUN for each "data unit" of
    configurable size in the request, e.g. for each filesystem block.

Property (1) makes it inefficient to use the traditional fscrypt
per-file keys.  Property (2) precludes the use of the existing
DIRECT_KEY fscrypt policy flag, which needs at least 192 IV bits.

Therefore, add a new fscrypt policy flag IV_INO_LBLK_64 which causes the
encryption to modified as follows:

- The encryption keys are derived from the master key, encryption mode
  number, and filesystem UUID.

- The IVs are chosen as (inode_number << 32) | file_logical_block_num.
  For filenames encryption, file_logical_block_num is 0.

Since the file nonces aren't used in the key derivation, many files may
share the same encryption key.  This is much more efficient on the
target hardware.  Including the inode number in the IVs and mixing the
filesystem UUID into the keys ensures that data in different files is
nevertheless still encrypted differently.

Additionally, limiting the inode and block numbers to 32 bits and
placing the block number in the low bits maintains compatibility with
the 64-bit DUN convention (property (2) above).

Since this scheme assumes that inode numbers are stable (which may
preclude filesystem shrinking) and that inode and file logical block
numbers are at most 32-bit, IV_INO_LBLK_64 will only be allowed on
filesystems that meet these constraints.  These are acceptable
limitations for the cases where this format would actually be used.

Note that IV_INO_LBLK_64 is an on-disk format, not an implementation.
This patch just adds support for it using the existing filesystem layer
encryption.  A later patch will add support for inline encryption.

Co-developed-by: Satya Tangirala <satyat@google.com>
Signed-off-by: Satya Tangirala <satyat@google.com>
Signed-off-by: Eric Biggers <ebiggers@google.com>

Change-Id: Iedecd7fa1ce8eefffdec57257e27e679938b0ad7
Signed-off-by: Satya Tangirala <satyat@google.com>
Link: https://patchwork.kernel.org/patch/11210909/
(cherry picked from commit 94231712cf)
2020-05-30 02:04:18 +08:00
Eric Biggers
0414c6a4a7 Remove the old inline encryption implementation
Remove all the inline encryption / ICE code, since we're replacing it
with a new implementation based on the new blk-crypto framework from
android-4.19 (and proposed upstream).

Bug: 147259927
Change-Id: Iff9a304ff92cbf87e3fb838878c235c2f518e8e8
2020-05-30 02:04:16 +08:00
Jaegeuk Kim
955e386d7f Merge remote-tracking branch 'aosp/upstream-f2fs-stable-linux-4.19.y' into android-4.19
* aosp/upstream-f2fs-stable-linux-4.19.y:
  f2fs: add a condition to detect overflow in f2fs_ioc_gc_range()
  f2fs: fix to add missing F2FS_IO_ALIGNED() condition
  f2fs: fix to fallback to buffered IO in IO aligned mode
  f2fs: fix to handle error path correctly in f2fs_map_blocks
  f2fs: fix extent corrupotion during directIO in LFS mode
  f2fs: check all the data segments against all node ones
  f2fs: Add a small clarification to CONFIG_FS_F2FS_FS_SECURITY
  f2fs: fix inode rwsem regression
  f2fs: fix to avoid accessing uninitialized field of inode page in is_alive()
  f2fs: avoid infinite GC loop due to stale atomic files
  f2fs: Fix indefinite loop in f2fs_gc()
  f2fs: convert inline_data in prior to i_size_write
  f2fs: fix error path of f2fs_convert_inline_page()
  f2fs: add missing documents of reserve_root/resuid/resgid
  f2fs: fix flushing node pages when checkpoint is disabled
  f2fs: enhance f2fs_is_checkpoint_ready()'s readability
  f2fs: clean up __bio_alloc()'s parameter
  f2fs: fix wrong error injection path in inc_valid_block_count()
  f2fs: fix to writeout dirty inode during node flush
  f2fs: optimize case-insensitive lookups
  f2fs: introduce f2fs_match_name() for cleanup
  f2fs: Fix indefinite loop in f2fs_gc()
  f2fs: allocate memory in batch in build_sit_info()
  f2fs: support FS_IOC_{GET,SET}FSLABEL
  f2fs: fix to avoid data corruption by forbidding SSR overwrite
  f2fs: Fix build error while CONFIG_NLS=m
  Revert "f2fs: avoid out-of-range memory access"
  f2fs: cleanup the code in build_sit_entries.
  f2fs: fix wrong available node count calculation
  f2fs: remove duplicate code in f2fs_file_write_iter
  f2fs: fix to migrate blocks correctly during defragment
  f2fs: use wrapped f2fs_cp_error()
  f2fs: fix to use more generic EOPNOTSUPP
  f2fs: use wrapped IS_SWAPFILE()
  f2fs: Support case-insensitive file name lookups
  f2fs: include charset encoding information in the superblock
  fs: Reserve flag for casefolding
  f2fs: fix to avoid call kvfree under spinlock
  fs: f2fs: Remove unnecessary checks of SM_I(sbi) in update_general_status()
  f2fs: disallow direct IO in atomic write
  f2fs: fix to handle quota_{on,off} correctly
  f2fs: fix to detect cp error in f2fs_setxattr()
  f2fs: fix to spread f2fs_is_checkpoint_ready()
  f2fs: support fiemap() for directory inode
  f2fs: fix to avoid discard command leak
  f2fs: fix to avoid tagging SBI_QUOTA_NEED_REPAIR incorrectly
  f2fs: fix to drop meta/node pages during umount
  f2fs: disallow switching io_bits option during remount
  f2fs: fix panic of IO alignment feature
  f2fs: introduce {page,io}_is_mergeable() for readability
  f2fs: fix livelock in swapfile writes
  f2fs: add fs-verity support
  ext4: update on-disk format documentation for fs-verity
  ext4: add fs-verity read support
  ext4: add basic fs-verity support
  fs-verity: support builtin file signatures
  fs-verity: add SHA-512 support
  fs-verity: implement FS_IOC_MEASURE_VERITY ioctl
  fs-verity: implement FS_IOC_ENABLE_VERITY ioctl
  fs-verity: add data verification hooks for ->readpages()
  fs-verity: add the hook for file ->setattr()
  fs-verity: add the hook for file ->open()
  fs-verity: add inode and superblock fields
  fs-verity: add Kconfig and the helper functions for hashing
  fs: uapi: define verity bit for FS_IOC_GETFLAGS
  fs-verity: add UAPI header
  fs-verity: add MAINTAINERS file entry
  fs-verity: add a documentation file
  ext4: fix kernel oops caused by spurious casefold flag
  ext4: fix coverity warning on error path of filename setup
  ext4: optimize case-insensitive lookups
  ext4: fix dcache lookup of !casefolded directories
  unicode: update to Unicode 12.1.0 final
  unicode: add missing check for an error return from utf8lookup()
  ext4: export /sys/fs/ext4/feature/casefold if Unicode support is present
  unicode: refactor the rule for regenerating utf8data.h
  ext4: Support case-insensitive file name lookups
  ext4: include charset encoding information in the superblock
  unicode: update unicode database unicode version 12.1.0
  unicode: introduce test module for normalized utf8 implementation
  unicode: implement higher level API for string handling
  unicode: reduce the size of utf8data[]
  unicode: introduce code for UTF-8 normalization
  unicode: introduce UTF-8 character database
  ext4 crypto: fix to check feature status before get policy
  fscrypt: document the new ioctls and policy version
  ubifs: wire up new fscrypt ioctls
  f2fs: wire up new fscrypt ioctls
  ext4: wire up new fscrypt ioctls
  fscrypt: require that key be added when setting a v2 encryption policy
  fscrypt: add FS_IOC_REMOVE_ENCRYPTION_KEY_ALL_USERS ioctl
  fscrypt: allow unprivileged users to add/remove keys for v2 policies
  fscrypt: v2 encryption policy support
  fscrypt: add an HKDF-SHA512 implementation
  fscrypt: add FS_IOC_GET_ENCRYPTION_KEY_STATUS ioctl
  fscrypt: add FS_IOC_REMOVE_ENCRYPTION_KEY ioctl
  fscrypt: add FS_IOC_ADD_ENCRYPTION_KEY ioctl
  fscrypt: rename keyinfo.c to keysetup.c
  fscrypt: move v1 policy key setup to keysetup_v1.c
  fscrypt: refactor key setup code in preparation for v2 policies
  fscrypt: rename fscrypt_master_key to fscrypt_direct_key
  fscrypt: add ->ci_inode to fscrypt_info
  fscrypt: use FSCRYPT_* definitions, not FS_*
  fscrypt: use FSCRYPT_ prefix for uapi constants
  fs, fscrypt: move uapi definitions to new header <linux/fscrypt.h>
  fscrypt: use ENOPKG when crypto API support missing
  fscrypt: improve warnings for missing crypto API support
  fscrypt: improve warning messages for unsupported encryption contexts
  fscrypt: make fscrypt_msg() take inode instead of super_block
  fscrypt: clean up base64 encoding/decoding
  fscrypt: remove loadable module related code

 Conflicts:
	fs/ext4/ioctl.c
	fs/ext4/readpage.c

Bug: 141329812
Change-Id: I2e10c22a7c52982d073ac6897cc8aa4d5a811a38
Signed-off-by: Jaegeuk Kim <jaegeuk@google.com>
2020-05-30 01:53:03 +08:00