Bluetooth: Add support for deferring RFCOMM connection setup

In order to decide if listening RFCOMM sockets should be accept()ed
the BD_ADDR of the remote device needs to be known. This patch adds
a socket option which defines a timeout for deferring the actual
connection setup.

The connection setup is done after reading from the socket for the
first time. Until then writing to the socket returns ENOTCONN.

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

diff --git a/include/net/bluetooth/rfcomm.h b/include/net/bluetooth/rfcomm.h
index 4dc8d92a4638e993a5c097a484bebf4e3e9fa7ae..71b45f45968796bc8d55b2381d5a1bc246ace2a4 100644 (file)
--- a/include/net/bluetooth/rfcomm.h
+++ b/include/net/bluetooth/rfcomm.h
@@ -185,6 +185,7 @@ struct rfcomm_dlc {
        u8            out;
 
        u32           link_mode;
+       u32           defer_setup;
 
        uint          mtu;
        uint          cfc;
@@ -202,10 +203,11 @@ struct rfcomm_dlc {
 #define RFCOMM_RX_THROTTLED 0
 #define RFCOMM_TX_THROTTLED 1
 #define RFCOMM_TIMED_OUT    2
-#define RFCOMM_MSC_PENDING  3 
+#define RFCOMM_MSC_PENDING  3
 #define RFCOMM_AUTH_PENDING 4
 #define RFCOMM_AUTH_ACCEPT  5
 #define RFCOMM_AUTH_REJECT  6
+#define RFCOMM_DEFER_SETUP  7
 
 /* Scheduling flags and events */
 #define RFCOMM_SCHED_STATE  0
@@ -239,6 +241,7 @@ int  rfcomm_dlc_close(struct rfcomm_dlc *d, int reason);
 int  rfcomm_dlc_send(struct rfcomm_dlc *d, struct sk_buff *skb);
 int  rfcomm_dlc_set_modem_status(struct rfcomm_dlc *d, u8 v24_sig);
 int  rfcomm_dlc_get_modem_status(struct rfcomm_dlc *d, u8 *v24_sig);
+void rfcomm_dlc_accept(struct rfcomm_dlc *d);
 
 #define rfcomm_dlc_lock(d)     spin_lock(&d->lock)
 #define rfcomm_dlc_unlock(d)   spin_unlock(&d->lock)
@@ -333,7 +336,6 @@ struct rfcomm_dev_req {
        bdaddr_t src;
        bdaddr_t dst;
        u8       channel;
-       
 };
 
 struct rfcomm_dev_info {

diff --git a/net/bluetooth/rfcomm/core.c b/net/bluetooth/rfcomm/core.c
index acd84fd524b856c25cf1f7c40560c3a6726d7236..edee49e00fbfa4054ce8cba4c1434a1b1cec978b 100644 (file)
--- a/net/bluetooth/rfcomm/core.c
+++ b/net/bluetooth/rfcomm/core.c
@@ -421,9 +421,16 @@ static int __rfcomm_dlc_close(struct rfcomm_dlc *d, int err)
                        d, d->state, d->dlci, err, s);
 
        switch (d->state) {
-       case BT_CONNECTED:
-       case BT_CONFIG:
        case BT_CONNECT:
+       case BT_CONFIG:
+               if (test_and_clear_bit(RFCOMM_DEFER_SETUP, &d->flags)) {
+                       set_bit(RFCOMM_AUTH_REJECT, &d->flags);
+                       rfcomm_schedule(RFCOMM_SCHED_AUTH);
+                       break;
+               }
+               /* Fall through */
+
+       case BT_CONNECTED:
                d->state = BT_DISCONN;
                if (skb_queue_empty(&d->tx_queue)) {
                        rfcomm_send_disc(s, d->dlci);
@@ -434,6 +441,14 @@ static int __rfcomm_dlc_close(struct rfcomm_dlc *d, int err)
                }
                break;
 
+       case BT_OPEN:
+               if (test_and_clear_bit(RFCOMM_DEFER_SETUP, &d->flags)) {
+                       set_bit(RFCOMM_AUTH_REJECT, &d->flags);
+                       rfcomm_schedule(RFCOMM_SCHED_AUTH);
+                       break;
+               }
+               /* Fall through */
+
        default:
                rfcomm_dlc_clear_timer(d);
 
@@ -1162,7 +1177,7 @@ static int rfcomm_recv_disc(struct rfcomm_session *s, u8 dlci)
        return 0;
 }
 
-static void rfcomm_dlc_accept(struct rfcomm_dlc *d)
+void rfcomm_dlc_accept(struct rfcomm_dlc *d)
 {
        struct sock *sk = d->session->sock->sk;
 
@@ -1181,6 +1196,20 @@ static void rfcomm_dlc_accept(struct rfcomm_dlc *d)
        rfcomm_send_msc(d->session, 1, d->dlci, d->v24_sig);
 }
 
+static void rfcomm_check_accept(struct rfcomm_dlc *d)
+{
+       if (rfcomm_check_link_mode(d)) {
+               set_bit(RFCOMM_AUTH_PENDING, &d->flags);
+               rfcomm_dlc_set_timer(d, RFCOMM_AUTH_TIMEOUT);
+       } else {
+               if (d->defer_setup) {
+                       set_bit(RFCOMM_DEFER_SETUP, &d->flags);
+                       rfcomm_dlc_set_timer(d, RFCOMM_AUTH_TIMEOUT);
+               } else
+                       rfcomm_dlc_accept(d);
+       }
+}
+
 static int rfcomm_recv_sabm(struct rfcomm_session *s, u8 dlci)
 {
        struct rfcomm_dlc *d;
@@ -1203,11 +1232,7 @@ static int rfcomm_recv_sabm(struct rfcomm_session *s, u8 dlci)
        if (d) {
                if (d->state == BT_OPEN) {
                        /* DLC was previously opened by PN request */
-                       if (rfcomm_check_link_mode(d)) {
-                               set_bit(RFCOMM_AUTH_PENDING, &d->flags);
-                               rfcomm_dlc_set_timer(d, RFCOMM_AUTH_TIMEOUT);
-                       } else
-                               rfcomm_dlc_accept(d);
+                       rfcomm_check_accept(d);
                }
                return 0;
        }
@@ -1219,11 +1244,7 @@ static int rfcomm_recv_sabm(struct rfcomm_session *s, u8 dlci)
                d->addr = __addr(s->initiator, dlci);
                rfcomm_dlc_link(s, d);
 
-               if (rfcomm_check_link_mode(d)) {
-                       set_bit(RFCOMM_AUTH_PENDING, &d->flags);
-                       rfcomm_dlc_set_timer(d, RFCOMM_AUTH_TIMEOUT);
-               } else
-                       rfcomm_dlc_accept(d);
+               rfcomm_check_accept(d);
        } else {
                rfcomm_send_dm(s, dlci);
        }
@@ -1717,8 +1738,13 @@ static inline void rfcomm_process_dlcs(struct rfcomm_session *s)
                        if (d->out) {
                                rfcomm_send_pn(s, 1, d);
                                rfcomm_dlc_set_timer(d, RFCOMM_CONN_TIMEOUT);
-                       } else
-                               rfcomm_dlc_accept(d);
+                       } else {
+                               if (d->defer_setup) {
+                                       set_bit(RFCOMM_DEFER_SETUP, &d->flags);
+                                       rfcomm_dlc_set_timer(d, RFCOMM_AUTH_TIMEOUT);
+                               } else
+                                       rfcomm_dlc_accept(d);
+                       }
                        if (d->link_mode & RFCOMM_LM_SECURE) {
                                struct sock *sk = s->sock->sk;
                                hci_conn_change_link_key(l2cap_pi(sk)->conn->hcon);

diff --git a/net/bluetooth/rfcomm/sock.c b/net/bluetooth/rfcomm/sock.c
index 65dd7133d72bf92e3d4a1b3e190aa14ecac107ce..d37a829a81e47d3dc3e41788d74955c9222fe72f 100644 (file)
--- a/net/bluetooth/rfcomm/sock.c
+++ b/net/bluetooth/rfcomm/sock.c
@@ -262,8 +262,10 @@ static void rfcomm_sock_init(struct sock *sk, struct sock *parent)
        if (parent) {
                sk->sk_type = parent->sk_type;
                pi->link_mode = rfcomm_pi(parent)->link_mode;
+               pi->dlc->defer_setup = bt_sk(parent)->defer_setup;
        } else {
                pi->link_mode = 0;
+               pi->dlc->defer_setup = 0;
        }
 
        pi->dlc->link_mode = pi->link_mode;
@@ -554,6 +556,9 @@ static int rfcomm_sock_sendmsg(struct kiocb *iocb, struct socket *sock,
        struct sk_buff *skb;
        int sent = 0;
 
+       if (test_bit(RFCOMM_DEFER_SETUP, &d->flags))
+               return -ENOTCONN;
+
        if (msg->msg_flags & MSG_OOB)
                return -EOPNOTSUPP;
 
@@ -633,10 +638,16 @@ static int rfcomm_sock_recvmsg(struct kiocb *iocb, struct socket *sock,
                               struct msghdr *msg, size_t size, int flags)
 {
        struct sock *sk = sock->sk;
+       struct rfcomm_dlc *d = rfcomm_pi(sk)->dlc;
        int err = 0;
        size_t target, copied = 0;
        long timeo;
 
+       if (test_and_clear_bit(RFCOMM_DEFER_SETUP, &d->flags)) {
+               rfcomm_dlc_accept(d);
+               return 0;
+       }
+
        if (flags & MSG_OOB)
                return -EOPNOTSUPP;
 
@@ -746,6 +757,7 @@ static int rfcomm_sock_setsockopt(struct socket *sock, int level, int optname, c
 {
        struct sock *sk = sock->sk;
        int err = 0;
+       u32 opt;
 
        BT_DBG("sk %p", sk);
 
@@ -755,6 +767,20 @@ static int rfcomm_sock_setsockopt(struct socket *sock, int level, int optname, c
        lock_sock(sk);
 
        switch (optname) {
+       case BT_DEFER_SETUP:
+               if (sk->sk_state != BT_BOUND && sk->sk_state != BT_LISTEN) {
+                       err = -EINVAL;
+                       break;
+               }
+
+               if (get_user(opt, (u32 __user *) optval)) {
+                       err = -EFAULT;
+                       break;
+               }
+
+               bt_sk(sk)->defer_setup = opt;
+               break;
+
        default:
                err = -ENOPROTOOPT;
                break;
@@ -785,7 +811,8 @@ static int rfcomm_sock_getsockopt_old(struct socket *sock, int optname, char __u
                break;
 
        case RFCOMM_CONNINFO:
-               if (sk->sk_state != BT_CONNECTED) {
+               if (sk->sk_state != BT_CONNECTED &&
+                                       !rfcomm_pi(sk)->dlc->defer_setup) {
                        err = -ENOTCONN;
                        break;
                }
@@ -826,6 +853,17 @@ static int rfcomm_sock_getsockopt(struct socket *sock, int level, int optname, c
        lock_sock(sk);
 
        switch (optname) {
+       case BT_DEFER_SETUP:
+               if (sk->sk_state != BT_BOUND && sk->sk_state != BT_LISTEN) {
+                       err = -EINVAL;
+                       break;
+               }
+
+               if (put_user(bt_sk(sk)->defer_setup, (u32 __user *) optval))
+                       err = -EFAULT;
+
+               break;
+
        default:
                err = -ENOPROTOOPT;
                break;
@@ -938,6 +976,10 @@ int rfcomm_connect_ind(struct rfcomm_session *s, u8 channel, struct rfcomm_dlc *
 
 done:
        bh_unlock_sock(parent);
+
+       if (bt_sk(parent)->defer_setup)
+               parent->sk_state_change(parent);
+
        return result;
 }