Bluetooth: Allow setting of L2CAP ERTM via socket option

To enable Enhanced Retransmission mode it needs to be set via a socket
option. A different mode can be set on a socket, but on listen() and
connect() the mode is checked and ERTM is only allowed if it is enabled
via the module parameter.

Signed-off-by: Marcel Holtmann <marcel@holtmann.org>

diff --git a/include/net/bluetooth/l2cap.h b/include/net/bluetooth/l2cap.h
index e919fca..06b072f 100644 (file)
--- a/include/net/bluetooth/l2cap.h
+++ b/include/net/bluetooth/l2cap.h
@@ -190,7 +190,7 @@ struct l2cap_conf_rfc {
 #define L2CAP_MODE_RETRANS     0x01
 #define L2CAP_MODE_FLOWCTL     0x02
 #define L2CAP_MODE_ERTM                0x03
-#define L2CAP_MODE_STREAM      0x04
+#define L2CAP_MODE_STREAMING   0x04
 
 struct l2cap_disconn_req {
        __le16     dcid;
@@ -271,9 +271,11 @@ struct l2cap_pinfo {
        __u16           imtu;
        __u16           omtu;
        __u16           flush_to;
-       __u8            sec_level;
+       __u8            mode;
+       __u8            fcs;
+       __u8            sec_level;
        __u8            role_switch;
-       __u8            force_reliable;
+       __u8            force_reliable;
 
        __u8            conf_req[64];
        __u8            conf_len;

diff --git a/net/bluetooth/l2cap.c b/net/bluetooth/l2cap.c
index 810a3c1..8a59e57 100644 (file)
--- a/net/bluetooth/l2cap.c
+++ b/net/bluetooth/l2cap.c
@@ -717,12 +717,16 @@ static void l2cap_sock_init(struct sock *sk, struct sock *parent)
 
                pi->imtu = l2cap_pi(parent)->imtu;
                pi->omtu = l2cap_pi(parent)->omtu;
+               pi->mode = l2cap_pi(parent)->mode;
+               pi->fcs  = l2cap_pi(parent)->fcs;
                pi->sec_level = l2cap_pi(parent)->sec_level;
                pi->role_switch = l2cap_pi(parent)->role_switch;
                pi->force_reliable = l2cap_pi(parent)->force_reliable;
        } else {
                pi->imtu = L2CAP_DEFAULT_MTU;
                pi->omtu = 0;
+               pi->mode = L2CAP_MODE_BASIC;
+               pi->fcs  = L2CAP_FCS_CRC16;
                pi->sec_level = BT_SECURITY_LOW;
                pi->role_switch = 0;
                pi->force_reliable = 0;
@@ -958,6 +962,18 @@ static int l2cap_sock_connect(struct socket *sock, struct sockaddr *addr, int al
                goto done;
        }
 
+       switch (l2cap_pi(sk)->mode) {
+       case L2CAP_MODE_BASIC:
+               break;
+       case L2CAP_MODE_ERTM:
+               if (enable_ertm)
+                       break;
+               /* fall through */
+       default:
+               err = -ENOTSUPP;
+               goto done;
+       }
+
        switch (sk->sk_state) {
        case BT_CONNECT:
        case BT_CONNECT2:
@@ -1009,6 +1025,18 @@ static int l2cap_sock_listen(struct socket *sock, int backlog)
                goto done;
        }
 
+       switch (l2cap_pi(sk)->mode) {
+       case L2CAP_MODE_BASIC:
+               break;
+       case L2CAP_MODE_ERTM:
+               if (enable_ertm)
+                       break;
+               /* fall through */
+       default:
+               err = -ENOTSUPP;
+               goto done;
+       }
+
        if (!l2cap_pi(sk)->psm) {
                bdaddr_t *src = &bt_sk(sk)->src;
                u16 psm;
@@ -1259,7 +1287,7 @@ static int l2cap_sock_setsockopt_old(struct socket *sock, int optname, char __us
                opts.imtu     = l2cap_pi(sk)->imtu;
                opts.omtu     = l2cap_pi(sk)->omtu;
                opts.flush_to = l2cap_pi(sk)->flush_to;
-               opts.mode     = L2CAP_MODE_BASIC;
+               opts.mode     = l2cap_pi(sk)->mode;
 
                len = min_t(unsigned int, sizeof(opts), optlen);
                if (copy_from_user((char *) &opts, optval, len)) {
@@ -1267,8 +1295,9 @@ static int l2cap_sock_setsockopt_old(struct socket *sock, int optname, char __us
                        break;
                }
 
-               l2cap_pi(sk)->imtu  = opts.imtu;
-               l2cap_pi(sk)->omtu  = opts.omtu;
+               l2cap_pi(sk)->imtu = opts.imtu;
+               l2cap_pi(sk)->omtu = opts.omtu;
+               l2cap_pi(sk)->mode = opts.mode;
                break;
 
        case L2CAP_LM:
@@ -1381,7 +1410,7 @@ static int l2cap_sock_getsockopt_old(struct socket *sock, int optname, char __us
                opts.imtu     = l2cap_pi(sk)->imtu;
                opts.omtu     = l2cap_pi(sk)->omtu;
                opts.flush_to = l2cap_pi(sk)->flush_to;
-               opts.mode     = L2CAP_MODE_BASIC;
+               opts.mode     = l2cap_pi(sk)->mode;
 
                len = min_t(unsigned int, len, sizeof(opts));
                if (copy_to_user(optval, (char *) &opts, len))