Subject: [PATCH 19/36] Bluetooth: SMP: Use new AES library API

From: Eric Biggers <[email-masked]>
Date: Sun, 4 Jan 2026 21:12:52 -0800

Switch from the old AES library functions (which use struct
crypto_aes_ctx) to the new ones (which use struct aes_enckey).  This
eliminates the unnecessary computation and caching of the decryption
round keys.  The new AES en/decryption functions are also much faster
and use AES instructions when supported by the CPU.

Note: aes_encrypt_new() will be renamed to aes_encrypt() once all
callers of the old aes_encrypt() have been updated.

Signed-off-by: Eric Biggers <[email-masked]>
---
 net/bluetooth/smp.c | 8 ++++----
 1 file changed, 4 insertions(+), 4 deletions(-)

diff --git a/net/bluetooth/smp.c b/net/bluetooth/smp.c
index 3a1ce04a7a53..69007e510177 100644
--- a/net/bluetooth/smp.c
+++ b/net/bluetooth/smp.c
@@ -372,36 +372,36 @@ static int smp_h7(struct crypto_shash *tfm_cmac, const u8 w[16],
  * s1 and ah.
  */
 
 static int smp_e(const u8 *k, u8 *r)
 {
-	struct crypto_aes_ctx ctx;
+	struct aes_enckey aes;
 	uint8_t tmp[16], data[16];
 	int err;
 
 	SMP_DBG("k %16phN r %16phN", k, r);
 
 	/* The most significant octet of key corresponds to k[0] */
 	swap_buf(k, tmp, 16);
 
-	err = aes_expandkey(&ctx, tmp, 16);
+	err = aes_prepareenckey(&aes, tmp, 16);
 	if (err) {
 		BT_ERR("cipher setkey failed: %d", err);
 		return err;
 	}
 
 	/* Most significant octet of plaintextData corresponds to data[0] */
 	swap_buf(r, data, 16);
 
-	aes_encrypt(&ctx, data, data);
+	aes_encrypt_new(&aes, data, data);
 
 	/* Most significant octet of encryptedData corresponds to data[0] */
 	swap_buf(data, r, 16);
 
 	SMP_DBG("r %16phN", r);
 
-	memzero_explicit(&ctx, sizeof(ctx));
+	memzero_explicit(&aes, sizeof(aes));
 	return err;
 }
 
 static int smp_c1(const u8 k[16],
 		  const u8 r[16], const u8 preq[7], const u8 pres[7], u8 _iat,
-- 
2.52.0