Merge tag 'fscrypt-for-linus' of git://git.kernel.org/pub/scm/fs/fscrypt/fscrypt

Pull fscrypt updates from Eric Biggers:
 "This release, we add support for inline encryption via the blk-crypto
  framework which was added in 5.8.

  Now when an ext4 or f2fs filesystem is mounted with '-o inlinecrypt',
  the contents of encrypted files will be encrypted/decrypted via
  blk-crypto, instead of directly using the crypto API. This model
  allows taking advantage of the inline encryption hardware that is
  integrated into the UFS or eMMC host controllers on most mobile SoCs.

  Note that this is just an alternate implementation; the ciphertext
  written to disk stays the same.

  (This pull request does *not* include support for direct I/O on
  encrypted files, which blk-crypto makes possible, since that part is
  still being discussed.)

  Besides the above feature update, there are also a few fixes and
  cleanups, e.g. strengthening some memory barriers that may be too
  weak.

  All these patches have been in linux-next with no reported issues.
  I've also tested them with the fscrypt xfstests, as usual. It's also
  been tested that the inline encryption support works with the support
  for Qualcomm and Mediatek inline encryption hardware that will be in
  the scsi pull request for 5.9. Also, several SoC vendors are already
  using a previous, functionally equivalent version of these patches"

* tag 'fscrypt-for-linus' of git://git.kernel.org/pub/scm/fs/fscrypt/fscrypt:
  fscrypt: don't load ->i_crypt_info before it's known to be valid
  fscrypt: document inline encryption support
  fscrypt: use smp_load_acquire() for ->i_crypt_info
  fscrypt: use smp_load_acquire() for ->s_master_keys
  fscrypt: use smp_load_acquire() for fscrypt_prepared_key
  fscrypt: switch fscrypt_do_sha256() to use the SHA-256 library
  fscrypt: restrict IV_INO_LBLK_* to AES-256-XTS
  fscrypt: rename FS_KEY_DERIVATION_NONCE_SIZE
  fscrypt: add comments that describe the HKDF info strings
  ext4: add inline encryption support
  f2fs: add inline encryption support
  fscrypt: add inline encryption support
  fs: introduce SB_INLINECRYPT

1 files changed, 9 insertions, 11 deletions

diff --git a/fs/crypto/keysetup_v1.c b/fs/crypto/keysetup_v1.c
index 801b48c0cd7f..e4e707fb1100 100644
--- a/fs/crypto/keysetup_v1.c
+++ b/fs/crypto/keysetup_v1.c
@@ -45,7 +45,7 @@ static DEFINE_SPINLOCK(fscrypt_direct_keys_lock);
  * key is longer, then only the first 'derived_keysize' bytes are used.
  */
 static int derive_key_aes(const u8 *master_key,
-			  const u8 nonce[FS_KEY_DERIVATION_NONCE_SIZE],
+			  const u8 nonce[FSCRYPT_FILE_NONCE_SIZE],
 			  u8 *derived_key, unsigned int derived_keysize)
 {
 	int res = 0;
@@ -68,7 +68,7 @@ static int derive_key_aes(const u8 *master_key,
 	skcipher_request_set_callback(req,
 			CRYPTO_TFM_REQ_MAY_BACKLOG | CRYPTO_TFM_REQ_MAY_SLEEP,
 			crypto_req_done, &wait);
-	res = crypto_skcipher_setkey(tfm, nonce, FS_KEY_DERIVATION_NONCE_SIZE);
+	res = crypto_skcipher_setkey(tfm, nonce, FSCRYPT_FILE_NONCE_SIZE);
 	if (res < 0)
 		goto out;
 
@@ -146,7 +146,7 @@ struct fscrypt_direct_key {
 	struct hlist_node		dk_node;
 	refcount_t			dk_refcount;
 	const struct fscrypt_mode	*dk_mode;
-	struct crypto_skcipher		*dk_ctfm;
+	struct fscrypt_prepared_key	dk_key;
 	u8				dk_descriptor[FSCRYPT_KEY_DESCRIPTOR_SIZE];
 	u8				dk_raw[FSCRYPT_MAX_KEY_SIZE];
 };
@@ -154,7 +154,7 @@ struct fscrypt_direct_key {
 static void free_direct_key(struct fscrypt_direct_key *dk)
 {
 	if (dk) {
-		crypto_free_skcipher(dk->dk_ctfm);
+		fscrypt_destroy_prepared_key(&dk->dk_key);
 		kzfree(dk);
 	}
 }
@@ -199,6 +199,8 @@ find_or_insert_direct_key(struct fscrypt_direct_key *to_insert,
 			continue;
 		if (ci->ci_mode != dk->dk_mode)
 			continue;
+		if (!fscrypt_is_key_prepared(&dk->dk_key, ci))
+			continue;
 		if (crypto_memneq(raw_key, dk->dk_raw, ci->ci_mode->keysize))
 			continue;
 		/* using existing tfm with same (descriptor, mode, raw_key) */
@@ -231,13 +233,9 @@ fscrypt_get_direct_key(const struct fscrypt_info *ci, const u8 *raw_key)
 		return ERR_PTR(-ENOMEM);
 	refcount_set(&dk->dk_refcount, 1);
 	dk->dk_mode = ci->ci_mode;
-	dk->dk_ctfm = fscrypt_allocate_skcipher(ci->ci_mode, raw_key,
-						ci->ci_inode);
-	if (IS_ERR(dk->dk_ctfm)) {
-		err = PTR_ERR(dk->dk_ctfm);
-		dk->dk_ctfm = NULL;
+	err = fscrypt_prepare_key(&dk->dk_key, raw_key, ci);
+	if (err)
 		goto err_free_dk;
-	}
 	memcpy(dk->dk_descriptor, ci->ci_policy.v1.master_key_descriptor,
 	       FSCRYPT_KEY_DESCRIPTOR_SIZE);
 	memcpy(dk->dk_raw, raw_key, ci->ci_mode->keysize);
@@ -259,7 +257,7 @@ static int setup_v1_file_key_direct(struct fscrypt_info *ci,
 	if (IS_ERR(dk))
 		return PTR_ERR(dk);
 	ci->ci_direct_key = dk;
-	ci->ci_ctfm = dk->dk_ctfm;
+	ci->ci_enc_key = dk->dk_key;
 	return 0;
 }