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From:   Vladis Dronov <vdronov@redhat.com>
To:     nstange@suse.de
Cc:     davem@davemloft.net, herbert@gondor.apana.org.au,
        linux-crypto@vger.kernel.org, linux-kernel@vger.kernel.org,
        smueller@chronox.de, vdronov@redhat.com
Subject: [PATCH 6/6] crypto: xts - drop redundant xts key check
Date:   Wed, 21 Dec 2022 16:26:13 +0100
Message-Id: <20221221152613.8655-1-vdronov@redhat.com>
In-Reply-To: <20221108142025.13461-1-nstange@suse.de>
References: <20221108142025.13461-1-nstange@suse.de>
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xts_fallback_setkey() in xts_aes_set_key() will now enforce key size
rule in FIPS mode when setting up the fallback algorithm keys, which
makes the check in xts_aes_set_key() redundant or unreachable. So just
drop this check.

xts_fallback_setkey() now makes a key size check in xts_verify_key():

xts_fallback_setkey()
  crypto_skcipher_setkey() [ skcipher_setkey_unaligned() ]
    cipher->setkey() { .setkey = xts_setkey }
      xts_setkey()
        xts_verify_key()

Signed-off-by: Vladis Dronov <vdronov@redhat.com>
---
 arch/s390/crypto/aes_s390.c | 4 ----
 1 file changed, 4 deletions(-)

diff --git a/arch/s390/crypto/aes_s390.c b/arch/s390/crypto/aes_s390.c
index 526c3f40f6a2..c773820e4af9 100644
--- a/arch/s390/crypto/aes_s390.c
+++ b/arch/s390/crypto/aes_s390.c
@@ -398,10 +398,6 @@ static int xts_aes_set_key(struct crypto_skcipher *tfm, const u8 *in_key,
 	if (err)
 		return err;
 
-	/* In fips mode only 128 bit or 256 bit keys are valid */
-	if (fips_enabled && key_len != 32 && key_len != 64)
-		return -EINVAL;
-
 	/* Pick the correct function code based on the key length */
 	fc = (key_len == 32) ? CPACF_KM_XTS_128 :
 	     (key_len == 64) ? CPACF_KM_XTS_256 : 0;
-- 
2.37.2