[Bluetooth] Export details about authentication requirements

With the Simple Pairing support, the authentication requirements are
an explicit setting during the bonding process. Track and enforce the
requirements and allow higher layers like L2CAP and RFCOMM to increase
them if needed.

This patch introduces a new IOCTL that allows to query the current
authentication requirements. It is also possible to detect Simple
Pairing support in the kernel this way.
Signed-off-by: Marcel Holtmann <marcel@holtmann.org>

fs/compat_ioctl.c

@@ -2399,6 +2399,7 @@ COMPATIBLE_IOCTL(HCIGETDEVLIST)
 COMPATIBLE_IOCTL(HCIGETDEVINFO)
 COMPATIBLE_IOCTL(HCIGETCONNLIST)
 COMPATIBLE_IOCTL(HCIGETCONNINFO)
+COMPATIBLE_IOCTL(HCIGETAUTHINFO)
 COMPATIBLE_IOCTL(HCISETRAW)
 COMPATIBLE_IOCTL(HCISETSCAN)
 COMPATIBLE_IOCTL(HCISETAUTH)

include/net/bluetooth/hci.h

@@ -72,8 +72,6 @@ enum {
 	HCI_INQUIRY,
 
 	HCI_RAW,
-
-	HCI_SECMGR
 };
 
 /* HCI ioctl defines */
@@ -86,6 +84,7 @@ enum {
 #define HCIGETDEVINFO	_IOR('H', 211, int)
 #define HCIGETCONNLIST	_IOR('H', 212, int)
 #define HCIGETCONNINFO	_IOR('H', 213, int)
+#define HCIGETAUTHINFO	_IOR('H', 215, int)
 
 #define HCISETRAW	_IOW('H', 220, int)
 #define HCISETSCAN	_IOW('H', 221, int)
@@ -97,8 +96,6 @@ enum {
 #define HCISETACLMTU	_IOW('H', 227, int)
 #define HCISETSCOMTU	_IOW('H', 228, int)
 
-#define HCISETSECMGR	_IOW('H', 230, int)
-
 #define HCIINQUIRY	_IOR('H', 240, int)
 
 /* HCI timeouts */
@@ -203,6 +200,14 @@ enum {
 #define HCI_LM_RELIABLE	0x0010
 #define HCI_LM_SECURE	0x0020
 
+/* Authentication types */
+#define HCI_AT_NO_BONDING		0x00
+#define HCI_AT_NO_BONDING_MITM		0x01
+#define HCI_AT_DEDICATED_BONDING	0x02
+#define HCI_AT_DEDICATED_BONDING_MITM	0x03
+#define HCI_AT_GENERAL_BONDING		0x04
+#define HCI_AT_GENERAL_BONDING_MITM	0x05
+
 /* -----  HCI Commands ---- */
 #define HCI_OP_INQUIRY			0x0401
 struct hci_cp_inquiry {
@@ -1001,6 +1006,11 @@ struct hci_conn_info_req {
 	struct   hci_conn_info conn_info[0];
 };
 
+struct hci_auth_info_req {
+	bdaddr_t bdaddr;
+	__u8     type;
+};
+
 struct hci_inquiry_req {
 	__u16 dev_id;
 	__u16 flags;

include/net/bluetooth/hci_core.h

@@ -168,6 +168,7 @@ struct hci_conn {
 	__u16            pkt_type;
 	__u16            link_policy;
 	__u32		 link_mode;
+	__u8             auth_type;
 	__u8             power_save;
 	unsigned long	 pend;
 
@@ -422,6 +423,7 @@ int hci_get_dev_list(void __user *arg);
 int hci_get_dev_info(void __user *arg);
 int hci_get_conn_list(void __user *arg);
 int hci_get_conn_info(struct hci_dev *hdev, void __user *arg);
+int hci_get_auth_info(struct hci_dev *hdev, void __user *arg);
 int hci_inquiry(void __user *arg);
 
 void hci_event_packet(struct hci_dev *hdev, struct sk_buff *skb);

net/bluetooth/hci_conn.c

@@ -379,13 +379,21 @@ int hci_conn_auth(struct hci_conn *conn)
 {
 	BT_DBG("conn %p", conn);
 
+	if (conn->ssp_mode > 0 && conn->hdev->ssp_mode > 0) {
+		if (!(conn->auth_type & 0x01)) {
+			conn->auth_type = HCI_AT_GENERAL_BONDING_MITM;
+			conn->link_mode &= ~HCI_LM_AUTH;
+		}
+	}
+
 	if (conn->link_mode & HCI_LM_AUTH)
 		return 1;
 
 	if (!test_and_set_bit(HCI_CONN_AUTH_PEND, &conn->pend)) {
 		struct hci_cp_auth_requested cp;
 		cp.handle = cpu_to_le16(conn->handle);
-		hci_send_cmd(conn->hdev, HCI_OP_AUTH_REQUESTED, sizeof(cp), &cp);
+		hci_send_cmd(conn->hdev, HCI_OP_AUTH_REQUESTED,
+							sizeof(cp), &cp);
 	}
 	return 0;
 }
@@ -397,7 +405,7 @@ int hci_conn_encrypt(struct hci_conn *conn)
 	BT_DBG("conn %p", conn);
 
 	if (conn->link_mode & HCI_LM_ENCRYPT)
-		return 1;
+		return hci_conn_auth(conn);
 
 	if (test_and_set_bit(HCI_CONN_ENCRYPT_PEND, &conn->pend))
 		return 0;
@@ -406,7 +414,8 @@ int hci_conn_encrypt(struct hci_conn *conn)
 		struct hci_cp_set_conn_encrypt cp;
 		cp.handle  = cpu_to_le16(conn->handle);
 		cp.encrypt = 1;
-		hci_send_cmd(conn->hdev, HCI_OP_SET_CONN_ENCRYPT, sizeof(cp), &cp);
+		hci_send_cmd(conn->hdev, HCI_OP_SET_CONN_ENCRYPT,
+							sizeof(cp), &cp);
 	}
 	return 0;
 }
@@ -420,7 +429,8 @@ int hci_conn_change_link_key(struct hci_conn *conn)
 	if (!test_and_set_bit(HCI_CONN_AUTH_PEND, &conn->pend)) {
 		struct hci_cp_change_conn_link_key cp;
 		cp.handle = cpu_to_le16(conn->handle);
-		hci_send_cmd(conn->hdev, HCI_OP_CHANGE_CONN_LINK_KEY, sizeof(cp), &cp);
+		hci_send_cmd(conn->hdev, HCI_OP_CHANGE_CONN_LINK_KEY,
+							sizeof(cp), &cp);
 	}
 	return 0;
 }
@@ -624,3 +634,23 @@ int hci_get_conn_info(struct hci_dev *hdev, void __user *arg)
 
 	return copy_to_user(ptr, &ci, sizeof(ci)) ? -EFAULT : 0;
 }
+
+int hci_get_auth_info(struct hci_dev *hdev, void __user *arg)
+{
+	struct hci_auth_info_req req;
+	struct hci_conn *conn;
+
+	if (copy_from_user(&req, arg, sizeof(req)))
+		return -EFAULT;
+
+	hci_dev_lock_bh(hdev);
+	conn = hci_conn_hash_lookup_ba(hdev, ACL_LINK, &req.bdaddr);
+	if (conn)
+		req.type = conn->auth_type;
+	hci_dev_unlock_bh(hdev);
+
+	if (!conn)
+		return -ENOENT;
+
+	return copy_to_user(arg, &req, sizeof(req)) ? -EFAULT : 0;
+}

net/bluetooth/hci_sock.c

@@ -193,19 +193,11 @@ static inline int hci_sock_bound_ioctl(struct sock *sk, unsigned int cmd, unsign
 
 		return 0;
 
-	case HCISETSECMGR:
-		if (!capable(CAP_NET_ADMIN))
-			return -EACCES;
-
-		if (arg)
-			set_bit(HCI_SECMGR, &hdev->flags);
-		else
-			clear_bit(HCI_SECMGR, &hdev->flags);
-
-		return 0;
-
 	case HCIGETCONNINFO:
-		return hci_get_conn_info(hdev, (void __user *)arg);
+		return hci_get_conn_info(hdev, (void __user *) arg);
+
+	case HCIGETAUTHINFO:
+		return hci_get_auth_info(hdev, (void __user *) arg);
 
 	default:
 		if (hdev->ioctl)
@@ -217,7 +209,7 @@ static inline int hci_sock_bound_ioctl(struct sock *sk, unsigned int cmd, unsign
 static int hci_sock_ioctl(struct socket *sock, unsigned int cmd, unsigned long arg)
 {
 	struct sock *sk = sock->sk;
-	void __user *argp = (void __user *)arg;
+	void __user *argp = (void __user *) arg;
 	int err;
 
 	BT_DBG("cmd %x arg %lx", cmd, arg);

net/bluetooth/l2cap.c

@@ -2150,7 +2150,7 @@ static int l2cap_disconn_ind(struct hci_conn *hcon, u8 reason)
 static int l2cap_auth_cfm(struct hci_conn *hcon, u8 status)
 {
 	struct l2cap_chan_list *l;
-	struct l2cap_conn *conn = conn = hcon->l2cap_data;
+	struct l2cap_conn *conn = hcon->l2cap_data;
 	struct l2cap_conn_rsp rsp;
 	struct sock *sk;
 	int result;
@@ -2165,11 +2165,17 @@ static int l2cap_auth_cfm(struct hci_conn *hcon, u8 status)
 	read_lock(&l->lock);
 
 	for (sk = l->head; sk; sk = l2cap_pi(sk)->next_c) {
+		struct l2cap_pinfo *pi = l2cap_pi(sk);
+
 		bh_lock_sock(sk);
 
-		if (sk->sk_state != BT_CONNECT2 ||
-				(l2cap_pi(sk)->link_mode & L2CAP_LM_ENCRYPT) ||
-				(l2cap_pi(sk)->link_mode & L2CAP_LM_SECURE)) {
+		if (sk->sk_state != BT_CONNECT2) {
+			bh_unlock_sock(sk);
+			continue;
+		}
+
+		if ((pi->link_mode & (L2CAP_LM_ENCRYPT | L2CAP_LM_SECURE)) &&
+					!(hcon->link_mode & HCI_LM_ENCRYPT)) {
 			bh_unlock_sock(sk);
 			continue;
 		}

net/bluetooth/rfcomm/core.c

@@ -1969,7 +1969,8 @@ static void rfcomm_auth_cfm(struct hci_conn *conn, u8 status)
 	list_for_each_safe(p, n, &s->dlcs) {
 		d = list_entry(p, struct rfcomm_dlc, list);
 
-		if (d->link_mode & (RFCOMM_LM_ENCRYPT | RFCOMM_LM_SECURE))
+		if ((d->link_mode & (RFCOMM_LM_ENCRYPT | RFCOMM_LM_SECURE)) &&
+				!(conn->link_mode & HCI_LM_ENCRYPT) && !status)
 			continue;
 
 		if (!test_and_clear_bit(RFCOMM_AUTH_PENDING, &d->flags))