Re: [PATCH v1 1/1] dm-inlinecrypt: initialize blk-crypto key as HW-wrapped key
Linlin Zhang <[email protected]>
| Newsgroups | dev.linux.lists.dm-devel,org.kernel.vger.linux-kernel |
|---|---|
| Message-ID | <[email protected]> |
On 5/14/2026 1:22 AM, Eric Biggers wrote: > On Tue, May 12, 2026 at 06:53:35PM +0000, Eric Biggers wrote: >> On Tue, May 12, 2026 at 02:52:03AM -0700, Linlin Zhang wrote: >>> dm-inlinecrypt currently initializes the blk-crypto key using >>> BLK_CRYPTO_KEY_TYPE_RAW, which implies that the provided key material >>> is a plaintext software key owned by the block layer. >>> >>> However, on platforms where dm-inlinecrypt is used together with a >>> hardware-backed key source (e.g. TrustZone/TEE or other secure key >>> wrapping mechanisms), the key material passed down is already wrapped >>> and must be treated as opaque by the block layer. >>> >>> Initialize the blk-crypto key using BLK_CRYPTO_KEY_TYPE_HW_WRAPPED >>> instead, so that dm-inlinecrypt correctly models hardware-wrapped keys >>> and avoids incorrect assumptions about key ownership and visibility. >>> >>> Signed-off-by: Linlin Zhang <[email protected]> >>> --- >>> drivers/md/dm-inlinecrypt.c | 2 +- >>> 1 file changed, 1 insertion(+), 1 deletion(-) >>> >>> diff --git a/drivers/md/dm-inlinecrypt.c b/drivers/md/dm-inlinecrypt.c >>> index bd8e58a028c5..bcbf363c533a 100644 >>> --- a/drivers/md/dm-inlinecrypt.c >>> +++ b/drivers/md/dm-inlinecrypt.c >>> @@ -386,7 +386,7 @@ static int inlinecrypt_ctr(struct dm_target *ti, unsigned int argc, char **argv) >>> dun_bytes = DIV_ROUND_UP(fls64(ctx->max_dun), 8); >>> >>> err = blk_crypto_init_key(&ctx->key, raw_key, ctx->key_size, >>> - BLK_CRYPTO_KEY_TYPE_RAW, >>> + BLK_CRYPTO_KEY_TYPE_HW_WRAPPED, >>> cipher->mode_num, dun_bytes, >>> ctx->sector_size); >> >> The raw key support is useful too, and it should be the default. >> I recommend adding a "wrappedkey" optional argument that enables >> BLK_CRYPTO_KEY_TYPE_HW_WRAPPED. > > This patch also makes the variable called "raw_key" contain a key that > isn't a raw key, which is confusing. "key_bytes" would make more sense > for a byte array that can contain either type of key. See e.g. > blk_crypto_init_key() which uses that naming convention. Thanks for your comment! ACK. Previously BLK_CRYPTO_KEY_TYPE_HW_WRAPPED was set for blk-crypto-profile entity by default, a raw key won't never passed down to ICE driver, so I replaced raw key type with wrapped key type directly. Now I see it already changed to query the supported type from ice. There isn't above concern. I'll update a new patch with both wrappedkey and raw key support and adding "wrappedkey" optional argument. replace "raw_key" with "key_bytes" as well. > > - Eric