2023-01-10 13:55:27

by Vincent Whitchurch

[permalink] [raw]
Subject: [PATCH 10/12] crypto: axis - fix XTS unaligned block size handling

The hardware does not implement ciphertext stealing so fallback to
software if the data length is not aligned to the block size. Fixes
this kind of errors with CRYPTO_MANAGER_EXTRA_TESTS:

alg: skcipher: artpec6-xts-aes encryption test failed (wrong result) on
test vector "random: len=151 klen=64", cfg="random: inplace_two_sglists
use_digest nosimd src_divs=[96.95%@+1949, 3.5%@+30]"

Signed-off-by: Vincent Whitchurch <[email protected]>
---
drivers/crypto/axis/artpec6_crypto.c | 22 ++++++++++++++++++++--
1 file changed, 20 insertions(+), 2 deletions(-)

diff --git a/drivers/crypto/axis/artpec6_crypto.c b/drivers/crypto/axis/artpec6_crypto.c
index 3b47faa06606..5eccb5a3a52e 100644
--- a/drivers/crypto/axis/artpec6_crypto.c
+++ b/drivers/crypto/axis/artpec6_crypto.c
@@ -1309,6 +1309,24 @@ static int artpec6_crypto_ctr_decrypt(struct skcipher_request *req)
return artpec6_crypto_ctr_crypt(req, false);
}

+static int artpec6_crypto_xts_encrypt(struct skcipher_request *req)
+{
+ /* Hardware does not implement ciphertext stealing */
+ if (!IS_ALIGNED(req->cryptlen, AES_BLOCK_SIZE))
+ return artpec6_crypto_crypt_fallback(req, true);
+
+ return artpec6_crypto_encrypt(req);
+}
+
+static int artpec6_crypto_xts_decrypt(struct skcipher_request *req)
+{
+ /* Hardware does not implement ciphertext stealing */
+ if (!IS_ALIGNED(req->cryptlen, AES_BLOCK_SIZE))
+ return artpec6_crypto_crypt_fallback(req, false);
+
+ return artpec6_crypto_decrypt(req);
+}
+
/*
* AEAD functions
*/
@@ -2928,8 +2946,8 @@ static struct skcipher_alg crypto_algos[] = {
.max_keysize = 2*AES_MAX_KEY_SIZE,
.ivsize = 16,
.setkey = artpec6_crypto_xts_set_key,
- .encrypt = artpec6_crypto_encrypt,
- .decrypt = artpec6_crypto_decrypt,
+ .encrypt = artpec6_crypto_xts_encrypt,
+ .decrypt = artpec6_crypto_xts_decrypt,
.init = artpec6_crypto_aes_xts_init,
.exit = artpec6_crypto_aes_exit,
},
--
2.34.1