From 524ef5ee1dd506145bacecc7da889e90c479748c Mon Sep 17 00:00:00 2001
From: Arkadiusz Lichwa <arkadiusz.lichwa@tieto.com>
Date: Mon, 4 Jan 2016 14:27:14 +0100
Subject: [PATCH] Bluetooth: Refactor type of keys as flags

Converts bt_keys type to atomic_t flags to enable consistent and
compact key type management.

Change-Id: Ie384168da6d5d0d1b305a33988ce7689ba3a4c6a
Signed-off-by: Arkadiusz Lichwa <arkadiusz.lichwa@tieto.com>
---
 net/bluetooth/conn.c     |  6 ++++--
 net/bluetooth/hci_core.c |  3 ++-
 net/bluetooth/keys.h     |  3 +--
 net/bluetooth/smp.c      | 31 +++++++++++++++----------------
 4 files changed, 22 insertions(+), 21 deletions(-)

diff --git a/net/bluetooth/conn.c b/net/bluetooth/conn.c
index 630e49c5c87..a2ce4af53e7 100644
--- a/net/bluetooth/conn.c
+++ b/net/bluetooth/conn.c
@@ -179,12 +179,14 @@ static int start_security(struct bt_conn *conn)
 		}
 
 		if (conn->required_sec_level > BT_SECURITY_MEDIUM &&
-		    conn->keys->type != BT_KEYS_AUTHENTICATED) {
+		    !atomic_test_bit(&conn->keys->flags,
+				     BT_KEYS_AUTHENTICATED)) {
 			return bt_smp_send_pairing_req(conn);
 		}
 
 		if (conn->required_sec_level > BT_SECURITY_HIGH &&
-		    conn->keys->type != BT_KEYS_AUTHENTICATED &&
+		    !atomic_test_bit(&conn->keys->flags,
+				     BT_KEYS_AUTHENTICATED) &&
 		    !(conn->keys->keys & BT_KEYS_LTK_P256)) {
 			return bt_smp_send_pairing_req(conn);
 		}
diff --git a/net/bluetooth/hci_core.c b/net/bluetooth/hci_core.c
index 9fec6073f5e..50e549ca945 100644
--- a/net/bluetooth/hci_core.c
+++ b/net/bluetooth/hci_core.c
@@ -817,7 +817,8 @@ static void update_sec_level(struct bt_conn *conn)
 		return;
 	}
 
-	if (conn->keys && conn->keys->type == BT_KEYS_AUTHENTICATED) {
+	if (conn->keys && atomic_test_bit(&conn->keys->flags,
+					  BT_KEYS_AUTHENTICATED)) {
 		if (conn->keys->keys & BT_KEYS_LTK_P256) {
 			conn->sec_level = BT_SECURITY_FIPS;
 		} else {
diff --git a/net/bluetooth/keys.h b/net/bluetooth/keys.h
index 6d57a683f4d..6ef3949e658 100644
--- a/net/bluetooth/keys.h
+++ b/net/bluetooth/keys.h
@@ -31,7 +31,6 @@ enum {
 };
 
 enum {
-	BT_KEYS_UNAUTHENTICATED,
 	BT_KEYS_AUTHENTICATED,
 };
 
@@ -54,7 +53,7 @@ struct bt_csrk {
 struct bt_keys {
 	bt_addr_le_t		addr;
 	int			keys;
-	uint8_t			type;
+	atomic_t		flags;
 	uint8_t			enc_size;
 
 #if !defined(CONFIG_BLUETOOTH_SMP_SC_ONLY)
diff --git a/net/bluetooth/smp.c b/net/bluetooth/smp.c
index 5ff4ec93fc0..157d0c5642b 100644
--- a/net/bluetooth/smp.c
+++ b/net/bluetooth/smp.c
@@ -1100,7 +1100,7 @@ static uint8_t legacy_request_tk(struct bt_smp *smp)
 	 * keys with unauthenticated ones.
 	  */
 	keys = bt_keys_find_addr(&conn->le.dst);
-	if (keys && keys->type == BT_KEYS_AUTHENTICATED &&
+	if (keys && atomic_test_bit(&keys->flags, BT_KEYS_AUTHENTICATED) &&
 	    smp->method == JUST_WORKS) {
 		BT_ERR("JustWorks failed, authenticated keys present");
 		return BT_SMP_ERR_UNSPECIFIED;
@@ -1752,19 +1752,6 @@ static uint8_t smp_pairing_confirm(struct bt_smp *smp, struct net_buf *buf)
 	return 0;
 }
 
-static uint8_t get_keys_type(uint8_t method)
-{
-	switch (method) {
-	case PASSKEY_DISPLAY:
-	case PASSKEY_INPUT:
-	case PASSKEY_CONFIRM:
-		return BT_KEYS_AUTHENTICATED;
-	case JUST_WORKS:
-	default:
-		return BT_KEYS_UNAUTHENTICATED;
-	}
-}
-
 static uint8_t sc_smp_send_dhkey_check(struct bt_smp *smp, const uint8_t *e)
 {
 	struct bt_smp_dhkey_check *req;
@@ -2271,7 +2258,7 @@ static uint8_t smp_security_request(struct bt_smp *smp, struct net_buf *buf)
 
 	/* if MITM required key must be authenticated */
 	if ((auth & BT_SMP_AUTH_MITM) &&
-	    conn->keys->type != BT_KEYS_AUTHENTICATED) {
+	    !atomic_test_bit(&conn->keys->flags, BT_KEYS_AUTHENTICATED)) {
 		if (get_io_capa() != BT_SMP_IO_NO_INPUT_OUTPUT) {
 			BT_INFO("New auth requirements: 0x%x, repairing",
 				auth);
@@ -3318,7 +3305,19 @@ void bt_smp_update_keys(struct bt_conn *conn)
 	 * it is important to store it since type is used to determine
 	 * security level upon encryption
 	 */
-	conn->keys->type = get_keys_type(smp->method);
+	switch (smp->method) {
+	case PASSKEY_DISPLAY:
+	case PASSKEY_INPUT:
+	case PASSKEY_CONFIRM:
+		atomic_set_bit(&conn->keys->flags, BT_KEYS_AUTHENTICATED);
+		break;
+	case JUST_WORKS:
+	default:
+		/* unauthenticated key, clear it */
+		atomic_clear_bit(&conn->keys->flags, BT_KEYS_AUTHENTICATED);
+		break;
+	}
+
 	conn->keys->enc_size = get_encryption_key_size(smp);
 
 	/*