Commit 6464f35f authored by Marcel Holtmann's avatar Marcel Holtmann Committed by David S. Miller
Browse files

[Bluetooth] Fall back to L2CAP in basic mode 



In case the remote entity tries to negogiate retransmission or flow
control mode, reject it and fall back to basic mode.

Signed-off-by: default avatarMarcel Holtmann <marcel@holtmann.org>
parent f0709e03

include/net/bluetooth/l2cap.h

+13 −0
Original line number Diff line number Diff line
@@ -149,6 +149,19 @@ struct l2cap_conf_opt { 


#define L2CAP_CONF_MAX_SIZE	22



struct l2cap_conf_rfc {

	__u8       mode;

	__u8       txwin_size;

	__u8       max_transmit;

	__le16     retrans_timeout;

	__le16     monitor_timeout;

	__le16     max_pdu_size;

} __attribute__ ((packed));



#define L2CAP_MODE_BASIC	0x00

#define L2CAP_MODE_RETRANS	0x01

#define L2CAP_MODE_FLOWCTL	0x02



struct l2cap_disconn_req {

	__le16     dcid;

	__le16     scid;

net/bluetooth/l2cap.c

+24 −8
Original line number Diff line number Diff line
@@ -1048,7 +1048,7 @@ static int l2cap_sock_setsockopt(struct socket *sock, int level, int optname, ch 
		opts.imtu     = l2cap_pi(sk)->imtu;

		opts.omtu     = l2cap_pi(sk)->omtu;

		opts.flush_to = l2cap_pi(sk)->flush_to;

		opts.mode     = 0x00;

		opts.mode     = L2CAP_MODE_BASIC;



		len = min_t(unsigned int, sizeof(opts), optlen);

		if (copy_from_user((char *) &opts, optval, len)) {
@@ -1097,7 +1097,7 @@ static int l2cap_sock_getsockopt(struct socket *sock, int level, int optname, ch 
		opts.imtu     = l2cap_pi(sk)->imtu;

		opts.omtu     = l2cap_pi(sk)->omtu;

		opts.flush_to = l2cap_pi(sk)->flush_to;

		opts.mode     = 0x00;

		opts.mode     = L2CAP_MODE_BASIC;



		len = min_t(unsigned int, len, sizeof(opts));

		if (copy_to_user(optval, (char *) &opts, len))
@@ -1376,6 +1376,7 @@ static int l2cap_parse_conf_req(struct sock *sk, void *data) 
	int len = pi->conf_len;

	int type, hint, olen;

	unsigned long val;

	struct l2cap_conf_rfc rfc = { .mode = L2CAP_MODE_BASIC };

	u16 mtu = L2CAP_DEFAULT_MTU;

	u16 result = L2CAP_CONF_SUCCESS;
@@ -1399,6 +1400,11 @@ static int l2cap_parse_conf_req(struct sock *sk, void *data) 
		case L2CAP_CONF_QOS:

			break;



		case L2CAP_CONF_RFC:

			if (olen == sizeof(rfc))

				memcpy(&rfc, (void *) val, olen);

			break;



		default:

			if (hint)

				break;
@@ -1413,6 +1419,7 @@ static int l2cap_parse_conf_req(struct sock *sk, void *data) 
		/* Configure output options and let the other side know

		 * which ones we don't like. */



		if (rfc.mode == L2CAP_MODE_BASIC) {

			if (mtu < pi->omtu)

				result = L2CAP_CONF_UNACCEPT;

			else {
@@ -1421,6 +1428,15 @@ static int l2cap_parse_conf_req(struct sock *sk, void *data) 
			}



			l2cap_add_conf_opt(&ptr, L2CAP_CONF_MTU, 2, pi->omtu);

		} else {

			result = L2CAP_CONF_UNACCEPT;



			memset(&rfc, 0, sizeof(rfc));

			rfc.mode = L2CAP_MODE_BASIC;



			l2cap_add_conf_opt(&ptr, L2CAP_CONF_RFC,

						sizeof(rfc), (unsigned long) &rfc);

		}

	}



	rsp->scid   = cpu_to_le16(pi->dcid);