From: Eric Biggers <ebiggers@google.com>
Date: Sun, 29 Oct 2023 05:03:55 +0000 (-0700)
Subject: ubifs: use crypto_shash_tfm_digest() in ubifs_hmac_wkm()
X-Git-Tag: v6.8-rc1~87^2~11
X-Git-Url: http://git.ipfire.org/?p=thirdparty%2Fkernel%2Flinux.git;a=commitdiff_plain;h=738fadaa549797c777650ac8d0d433fdc20152e3

ubifs: use crypto_shash_tfm_digest() in ubifs_hmac_wkm()

Simplify ubifs_hmac_wkm() by using crypto_shash_tfm_digest() instead of
an alloc+init+update+final sequence.  This should also improve
performance.

Signed-off-by: Eric Biggers <ebiggers@google.com>
Tested-by: Zhihao Cheng <chengzhihao1@huawei.com>
Signed-off-by: Richard Weinberger <richard@nod.at>
---

diff --git a/fs/ubifs/auth.c b/fs/ubifs/auth.c
index 0d561ecb68694..5c414d896c9bd 100644
--- a/fs/ubifs/auth.c
+++ b/fs/ubifs/auth.c
@@ -507,28 +507,13 @@ out:
  */
 int ubifs_hmac_wkm(struct ubifs_info *c, u8 *hmac)
 {
-	SHASH_DESC_ON_STACK(shash, c->hmac_tfm);
-	int err;
 	const char well_known_message[] = "UBIFS";
 
 	if (!ubifs_authenticated(c))
 		return 0;
 
-	shash->tfm = c->hmac_tfm;
-
-	err = crypto_shash_init(shash);
-	if (err)
-		return err;
-
-	err = crypto_shash_update(shash, well_known_message,
-				  sizeof(well_known_message) - 1);
-	if (err < 0)
-		return err;
-
-	err = crypto_shash_final(shash, hmac);
-	if (err)
-		return err;
-	return 0;
+	return crypto_shash_tfm_digest(c->hmac_tfm, well_known_message,
+				       sizeof(well_known_message) - 1, hmac);
 }
 
 /*