Commit b7e072f9 authored by Eric Biggers's avatar Eric Biggers
Browse files

fscrypt: improve a few comments 

Improve a few comments.  These were extracted from the patch
"fscrypt: add support for hardware-wrapped keys"
(https://lore.kernel.org/r/20211021181608.54127-4-ebiggers@kernel.org).

Link: https://lore.kernel.org/r/20211026021042.6581-1-ebiggers@kernel.org


Signed-off-by: default avatarEric Biggers <ebiggers@google.com>
parent 7f595d6a

fs/crypto/fscrypt_private.h

+10 −1
Original line number Diff line number Diff line
@@ -20,6 +20,11 @@ 


#define FSCRYPT_FILE_NONCE_SIZE	16



/*

 * Minimum size of an fscrypt master key.  Note: a longer key will be required

 * if ciphers with a 256-bit security strength are used.  This is just the

 * absolute minimum, which applies when only 128-bit encryption is used.

 */

#define FSCRYPT_MIN_KEY_SIZE	16



#define FSCRYPT_CONTEXT_V1	1
@@ -413,7 +418,11 @@ struct fscrypt_master_key_secret { 
	 */

	struct fscrypt_hkdf	hkdf;



	/* Size of the raw key in bytes.  Set even if ->raw isn't set. */

	/*

	 * Size of the raw key in bytes.  This remains set even if ->raw was

	 * zeroized due to no longer being needed.  I.e. we still remember the

	 * size of the key even if we don't need to remember the key itself.

	 */

	u32			size;



	/* For v1 policy keys: the raw key.  Wiped for v2 policy keys. */

fs/crypto/keysetup.c

+3 −2
Original line number Diff line number Diff line
@@ -122,8 +122,9 @@ fscrypt_allocate_skcipher(struct fscrypt_mode *mode, const u8 *raw_key, 


/*

 * Prepare the crypto transform object or blk-crypto key in @prep_key, given the

 * raw key, encryption mode, and flag indicating which encryption implementation

 * (fs-layer or blk-crypto) will be used.

 * raw key, encryption mode (@ci->ci_mode), flag indicating which encryption

 * implementation (fs-layer or blk-crypto) will be used (@ci->ci_inlinecrypt),

 * and IV generation method (@ci->ci_policy.flags).

 */

int fscrypt_prepare_key(struct fscrypt_prepared_key *prep_key,

			const u8 *raw_key, const struct fscrypt_info *ci)