diff options
| author | Eric Biggers <ebiggers@google.com> | 2025-02-03 22:00:37 -0800 |
|---|---|---|
| committer | Jens Axboe <axboe@kernel.dk> | 2025-02-10 09:54:19 -0700 |
| commit | 1ebd4a3c095cd538d3c1c7c12738ef47d8e71f96 (patch) | |
| tree | fe558921c4164578895912eff0c1f14cb617d320 /block/ioctl.c | |
| parent | e35fde43e25ad725d27315992fba8088d1210b01 (diff) | |
blk-crypto: add ioctls to create and prepare hardware-wrapped keys
Until this point, the kernel can use hardware-wrapped keys to do
encryption if userspace provides one -- specifically a key in
ephemerally-wrapped form. However, no generic way has been provided for
userspace to get such a key in the first place.
Getting such a key is a two-step process. First, the key needs to be
imported from a raw key or generated by the hardware, producing a key in
long-term wrapped form. This happens once in the whole lifetime of the
key. Second, the long-term wrapped key needs to be converted into
ephemerally-wrapped form. This happens each time the key is "unlocked".
In Android, these operations are supported in a generic way through
KeyMint, a userspace abstraction layer. However, that method is
Android-specific and can't be used on other Linux systems, may rely on
proprietary libraries, and also misleads people into supporting KeyMint
features like rollback resistance that make sense for other KeyMint keys
but don't make sense for hardware-wrapped inline encryption keys.
Therefore, this patch provides a generic kernel interface for these
operations by introducing new block device ioctls:
- BLKCRYPTOIMPORTKEY: convert a raw key to long-term wrapped form.
- BLKCRYPTOGENERATEKEY: have the hardware generate a new key, then
return it in long-term wrapped form.
- BLKCRYPTOPREPAREKEY: convert a key from long-term wrapped form to
ephemerally-wrapped form.
These ioctls are implemented using new operations in blk_crypto_ll_ops.
Signed-off-by: Eric Biggers <ebiggers@google.com>
Tested-by: Bartosz Golaszewski <bartosz.golaszewski@linaro.org> # sm8650
Link: https://lore.kernel.org/r/20250204060041.409950-4-ebiggers@kernel.org
Signed-off-by: Jens Axboe <axboe@kernel.dk>
Diffstat (limited to 'block/ioctl.c')
| -rw-r--r-- | block/ioctl.c | 5 |
1 files changed, 5 insertions, 0 deletions
diff --git a/block/ioctl.c b/block/ioctl.c index 6554b728bae6..faa40f383e27 100644 --- a/block/ioctl.c +++ b/block/ioctl.c @@ -15,6 +15,7 @@ #include <linux/io_uring/cmd.h> #include <uapi/linux/blkdev.h> #include "blk.h" +#include "blk-crypto-internal.h" static int blkpg_do_ioctl(struct block_device *bdev, struct blkpg_partition __user *upart, int op) @@ -620,6 +621,10 @@ static int blkdev_common_ioctl(struct block_device *bdev, blk_mode_t mode, case BLKTRACESTOP: case BLKTRACETEARDOWN: return blk_trace_ioctl(bdev, cmd, argp); + case BLKCRYPTOIMPORTKEY: + case BLKCRYPTOGENERATEKEY: + case BLKCRYPTOPREPAREKEY: + return blk_crypto_ioctl(bdev, cmd, argp); case IOC_PR_REGISTER: return blkdev_pr_register(bdev, mode, argp); case IOC_PR_RESERVE: |