linux/include
Eric Biggers c07d3aede2 fscrypt: add support for hardware-wrapped keys
Add support for hardware-wrapped keys to fscrypt.  Such keys are
protected from certain attacks, such as cold boot attacks.  For more
information, see the "Hardware-wrapped keys" section of
Documentation/block/inline-encryption.rst.

To support hardware-wrapped keys in fscrypt, we allow the fscrypt master
keys to be hardware-wrapped.  File contents encryption is done by
passing the wrapped key to the inline encryption hardware via
blk-crypto.  Other fscrypt operations such as filenames encryption
continue to be done by the kernel, using the "software secret" which the
hardware derives.  For more information, see the documentation which
this patch adds to Documentation/filesystems/fscrypt.rst.

Note that this feature doesn't require any filesystem-specific changes.
However it does depend on inline encryption support, and thus currently
it is only applicable to ext4 and f2fs.

The version of this feature introduced by this patch is mostly
equivalent to the version that has existed downstream in the Android
Common Kernels since 2020.  However, a couple fixes are included.
First, the flags field in struct fscrypt_add_key_arg is now placed in
the proper location.  Second, key identifiers for HW-wrapped keys are
now derived using a distinct HKDF context byte; this fixes a bug where a
raw key could have the same identifier as a HW-wrapped key.  Note that
as a result of these fixes, the version of this feature introduced by
this patch is not UAPI or on-disk format compatible with the version in
the Android Common Kernels, though the divergence is limited to just
those specific fixes.  This version should be used going forwards.

This patch has been heavily rewritten from the original version by
Gaurav Kashyap <quic_gaurkash@quicinc.com> and
Barani Muthukumaran <bmuthuku@codeaurora.org>.

Tested-by: Bartosz Golaszewski <bartosz.golaszewski@linaro.org> # sm8650
Link: https://lore.kernel.org/r/20250404225859.172344-1-ebiggers@kernel.org
Signed-off-by: Eric Biggers <ebiggers@google.com>
2025-04-08 19:32:11 -07:00
..
acpi misc: Constify amba_id table 2025-03-29 18:25:34 -07:00
asm-generic RISC-V Patches for the 6.15 Merge Window, Part 1 2025-04-04 09:49:17 -07:00
clocksource
crypto This update includes the following changes: 2025-03-29 10:01:55 -07:00
cxl cxl for v6.15 2025-04-02 20:04:43 -07:00
drm Rust changes for v6.15 2025-03-30 17:03:26 -07:00
dt-bindings Char/Misc/IIO driver updates for 6.15-rc1 2025-04-01 11:26:08 -07:00
hyperv x86/hyperv: Add comments about hv_vpset and var size hypercall input args 2025-03-21 18:24:22 +00:00
keys
kunit
kvm Merge branch 'kvm-arm64/pmu-fixes' into kvmarm/next 2025-03-19 14:54:52 -07:00
linux A set of final cleanups for the timer subsystem: 2025-04-06 08:35:37 -07:00
math-emu
media
memory
misc cxl: Remove driver 2025-03-16 22:04:27 +11:00
net treewide: Switch/rename to timer_delete[_sync]() 2025-04-05 10:30:12 +02:00
pcmcia
ras
rdma RDMA/core: Pass port to counter bind/unbind operations 2025-03-18 06:18:46 -04:00
rv
scsi
soc soc: driver updates for 6.15, part 1 2025-03-27 09:05:55 -07:00
sound soundwire updates for 6.15 2025-04-01 12:43:13 -07:00
target
trace tracing/timers: Rename the hrtimer_init event to hrtimer_setup 2025-04-05 10:30:17 +02:00
uapi fscrypt: add support for hardware-wrapped keys 2025-04-08 19:32:11 -07:00
ufs
vdso vdso: Rework struct vdso_time_data and introduce struct vdso_clock 2025-03-08 14:37:41 +01:00
video
xen xen/mcelog: Add __nonstring annotations for unterminated strings 2025-03-14 11:15:16 +01:00
Kbuild