Bluetooth: Remove unnecessary SMP STK define

We never store the "master" type of STKs since we request encryption
directly with them so we only need one STK type (the one that's
looked-up on the slave side). Simply remove the unnecessary define and
rename the _SLAVE one to the shorter form.
Signed-off-by: Johan Hedberg <johan.hedberg@intel.com>
Signed-off-by: Marcel Holtmann <marcel@holtmann.org>

include/net/bluetooth/hci.h

@@ -349,7 +349,6 @@ enum {
 #define HCI_LK_AUTH_COMBINATION_P256	0x08
 /* The spec doesn't define types for SMP keys, the _MASTER suffix is implied */
 #define HCI_SMP_STK			0x80
-#define HCI_SMP_STK_SLAVE		0x81
 #define HCI_SMP_LTK			0x82
 #define HCI_SMP_LTK_SLAVE		0x83
 

net/bluetooth/hci_event.c

@@ -4241,7 +4241,7 @@ static void hci_le_ltk_request_evt(struct hci_dev *hdev, struct sk_buff *skb)
 	 * distribute the keys. Later, security can be re-established
 	 * using a distributed LTK.
 	 */
-	if (ltk->type == HCI_SMP_STK_SLAVE) {
+	if (ltk->type == HCI_SMP_STK) {
 		list_del(&ltk->list);
 		kfree(ltk);
 	}

net/bluetooth/smp.c

@@ -568,8 +568,12 @@ static u8 smp_random(struct smp_chan *smp)
 		else
 			auth = 0;
 
+		/* Even though there's no _SLAVE suffix this is the
+		 * slave STK we're adding for later lookup (the master
+		 * STK never needs to be stored).
+		 */
 		hci_add_ltk(hcon->hdev, &hcon->dst, hcon->dst_type,
-			    HCI_SMP_STK_SLAVE, auth, stk, smp->enc_key_size,
+			    HCI_SMP_STK, auth, stk, smp->enc_key_size,
 			    ediv, rand);
 	}