Bluetooth: Select Basic Mode as default for SOCK_SEQPACKET
[safe/jmp/linux-2.6] / net / bluetooth / l2cap.c
index 7f835e7..076caa1 100644 (file)
@@ -41,6 +41,7 @@
 #include <linux/list.h>
 #include <linux/device.h>
 #include <linux/uaccess.h>
+#include <linux/crc16.h>
 #include <net/sock.h>
 
 #include <asm/system.h>
@@ -338,11 +339,14 @@ static inline int l2cap_send_sframe(struct l2cap_pinfo *pi, u16 control)
        struct sk_buff *skb;
        struct l2cap_hdr *lh;
        struct l2cap_conn *conn = pi->conn;
-       int count;
+       int count, hlen = L2CAP_HDR_SIZE + 2;
+
+       if (pi->fcs == L2CAP_FCS_CRC16)
+               hlen += 2;
 
        BT_DBG("pi %p, control 0x%2.2x", pi, control);
 
-       count = min_t(unsigned int, conn->mtu, L2CAP_HDR_SIZE + 2);
+       count = min_t(unsigned int, conn->mtu, hlen);
        control |= L2CAP_CTRL_FRAME_TYPE;
 
        skb = bt_skb_alloc(count, GFP_ATOMIC);
@@ -350,13 +354,28 @@ static inline int l2cap_send_sframe(struct l2cap_pinfo *pi, u16 control)
                return -ENOMEM;
 
        lh = (struct l2cap_hdr *) skb_put(skb, L2CAP_HDR_SIZE);
-       lh->len = cpu_to_le16(2);
+       lh->len = cpu_to_le16(hlen - L2CAP_HDR_SIZE);
        lh->cid = cpu_to_le16(pi->dcid);
        put_unaligned_le16(control, skb_put(skb, 2));
 
+       if (pi->fcs == L2CAP_FCS_CRC16) {
+               u16 fcs = crc16(0, (u8 *)lh, count - 2);
+               put_unaligned_le16(fcs, skb_put(skb, 2));
+       }
+
        return hci_send_acl(pi->conn->hcon, skb, 0);
 }
 
+static inline int l2cap_send_rr_or_rnr(struct l2cap_pinfo *pi, u16 control)
+{
+       if (pi->conn_state & L2CAP_CONN_LOCAL_BUSY)
+               control |= L2CAP_SUPER_RCV_NOT_READY;
+       else
+               control |= L2CAP_SUPER_RCV_READY;
+
+       return l2cap_send_sframe(pi, control);
+}
+
 static void l2cap_do_start(struct sock *sk)
 {
        struct l2cap_conn *conn = l2cap_pi(sk)->conn;
@@ -536,12 +555,12 @@ static struct l2cap_conn *l2cap_conn_add(struct hci_conn *hcon, u8 status)
 
        conn->feat_mask = 0;
 
-       setup_timer(&conn->info_timer, l2cap_info_timeout,
-                                               (unsigned long) conn);
-
        spin_lock_init(&conn->lock);
        rwlock_init(&conn->chan_list.lock);
 
+       setup_timer(&conn->info_timer, l2cap_info_timeout,
+                                               (unsigned long) conn);
+
        conn->disc_reason = 0x13;
 
        return conn;
@@ -764,6 +783,9 @@ static void l2cap_sock_init(struct sock *sk, struct sock *parent)
        /* Default config options */
        pi->conf_len = 0;
        pi->flush_to = L2CAP_DEFAULT_FLUSH_TO;
+       skb_queue_head_init(TX_QUEUE(sk));
+       skb_queue_head_init(SREJ_QUEUE(sk));
+       INIT_LIST_HEAD(SREJ_LIST(sk));
 }
 
 static struct proto l2cap_proto = {
@@ -1183,6 +1205,7 @@ static void l2cap_monitor_timeout(unsigned long arg)
        struct sock *sk = (void *) arg;
        u16 control;
 
+       bh_lock_sock(sk);
        if (l2cap_pi(sk)->retry_count >= l2cap_pi(sk)->remote_max_tx) {
                l2cap_send_disconn_req(l2cap_pi(sk)->conn, sk);
                return;
@@ -1192,8 +1215,8 @@ static void l2cap_monitor_timeout(unsigned long arg)
        __mod_monitor_timer();
 
        control = L2CAP_CTRL_POLL;
-       control |= L2CAP_SUPER_RCV_READY;
-       l2cap_send_sframe(l2cap_pi(sk), control);
+       l2cap_send_rr_or_rnr(l2cap_pi(sk), control);
+       bh_unlock_sock(sk);
 }
 
 static void l2cap_retrans_timeout(unsigned long arg)
@@ -1201,14 +1224,15 @@ static void l2cap_retrans_timeout(unsigned long arg)
        struct sock *sk = (void *) arg;
        u16 control;
 
+       bh_lock_sock(sk);
        l2cap_pi(sk)->retry_count = 1;
        __mod_monitor_timer();
 
        l2cap_pi(sk)->conn_state |= L2CAP_CONN_WAIT_F;
 
        control = L2CAP_CTRL_POLL;
-       control |= L2CAP_SUPER_RCV_READY;
-       l2cap_send_sframe(l2cap_pi(sk), control);
+       l2cap_send_rr_or_rnr(l2cap_pi(sk), control);
+       bh_unlock_sock(sk);
 }
 
 static void l2cap_drop_acked_frames(struct sock *sk)
@@ -1249,7 +1273,7 @@ static int l2cap_streaming_send(struct sock *sk)
 {
        struct sk_buff *skb, *tx_skb;
        struct l2cap_pinfo *pi = l2cap_pi(sk);
-       u16 control;
+       u16 control, fcs;
        int err;
 
        while ((skb = sk->sk_send_head)) {
@@ -1259,6 +1283,11 @@ static int l2cap_streaming_send(struct sock *sk)
                control |= pi->next_tx_seq << L2CAP_CTRL_TXSEQ_SHIFT;
                put_unaligned_le16(control, tx_skb->data + L2CAP_HDR_SIZE);
 
+               if (l2cap_pi(sk)->fcs == L2CAP_FCS_CRC16) {
+                       fcs = crc16(0, (u8 *)tx_skb->data, tx_skb->len - 2);
+                       put_unaligned_le16(fcs, tx_skb->data + tx_skb->len - 2);
+               }
+
                err = l2cap_do_send(sk, tx_skb);
                if (err < 0) {
                        l2cap_send_disconn_req(pi->conn, sk);
@@ -1278,17 +1307,62 @@ static int l2cap_streaming_send(struct sock *sk)
        return 0;
 }
 
+static int l2cap_retransmit_frame(struct sock *sk, u8 tx_seq)
+{
+       struct l2cap_pinfo *pi = l2cap_pi(sk);
+       struct sk_buff *skb, *tx_skb;
+       u16 control, fcs;
+       int err;
+
+       skb = skb_peek(TX_QUEUE(sk));
+       do {
+               if (bt_cb(skb)->tx_seq != tx_seq) {
+                       if (skb_queue_is_last(TX_QUEUE(sk), skb))
+                               break;
+                       skb = skb_queue_next(TX_QUEUE(sk), skb);
+                       continue;
+               }
+
+               if (pi->remote_max_tx &&
+                               bt_cb(skb)->retries == pi->remote_max_tx) {
+                       l2cap_send_disconn_req(pi->conn, sk);
+                       break;
+               }
+
+               tx_skb = skb_clone(skb, GFP_ATOMIC);
+               bt_cb(skb)->retries++;
+               control = get_unaligned_le16(tx_skb->data + L2CAP_HDR_SIZE);
+               control |= (pi->req_seq << L2CAP_CTRL_REQSEQ_SHIFT)
+                               | (tx_seq << L2CAP_CTRL_TXSEQ_SHIFT);
+               put_unaligned_le16(control, tx_skb->data + L2CAP_HDR_SIZE);
+
+               if (l2cap_pi(sk)->fcs == L2CAP_FCS_CRC16) {
+                       fcs = crc16(0, (u8 *)tx_skb->data, tx_skb->len - 2);
+                       put_unaligned_le16(fcs, tx_skb->data + tx_skb->len - 2);
+               }
+
+               err = l2cap_do_send(sk, tx_skb);
+               if (err < 0) {
+                       l2cap_send_disconn_req(pi->conn, sk);
+                       return err;
+               }
+               break;
+       } while(1);
+       return 0;
+}
+
 static int l2cap_ertm_send(struct sock *sk)
 {
        struct sk_buff *skb, *tx_skb;
        struct l2cap_pinfo *pi = l2cap_pi(sk);
-       u16 control;
+       u16 control, fcs;
        int err;
 
        if (pi->conn_state & L2CAP_CONN_WAIT_F)
                return 0;
 
-       while ((skb = sk->sk_send_head) && (!l2cap_tx_window_full(sk))) {
+       while ((skb = sk->sk_send_head) && (!l2cap_tx_window_full(sk))
+                       && !(pi->conn_state & L2CAP_CONN_REMOTE_BUSY)) {
                tx_skb = skb_clone(skb, GFP_ATOMIC);
 
                if (pi->remote_max_tx &&
@@ -1305,6 +1379,11 @@ static int l2cap_ertm_send(struct sock *sk)
                put_unaligned_le16(control, tx_skb->data + L2CAP_HDR_SIZE);
 
 
+               if (l2cap_pi(sk)->fcs == L2CAP_FCS_CRC16) {
+                       fcs = crc16(0, (u8 *)skb->data, tx_skb->len - 2);
+                       put_unaligned_le16(fcs, skb->data + tx_skb->len - 2);
+               }
+
                err = l2cap_do_send(sk, tx_skb);
                if (err < 0) {
                        l2cap_send_disconn_req(pi->conn, sk);
@@ -1428,6 +1507,9 @@ static struct sk_buff *l2cap_create_iframe_pdu(struct sock *sk, struct msghdr *m
        if (sdulen)
                hlen += 2;
 
+       if (l2cap_pi(sk)->fcs == L2CAP_FCS_CRC16)
+               hlen += 2;
+
        count = min_t(unsigned int, (conn->mtu - hlen), len);
        skb = bt_skb_send_alloc(sk, count + hlen,
                        msg->msg_flags & MSG_DONTWAIT, &err);
@@ -1448,6 +1530,9 @@ static struct sk_buff *l2cap_create_iframe_pdu(struct sock *sk, struct msghdr *m
                return ERR_PTR(err);
        }
 
+       if (l2cap_pi(sk)->fcs == L2CAP_FCS_CRC16)
+               put_unaligned_le16(0, skb_put(skb, 2));
+
        bt_cb(skb)->retries = 0;
        return skb;
 }
@@ -1616,7 +1701,7 @@ static int l2cap_sock_recvmsg(struct kiocb *iocb, struct socket *sock, struct ms
        return bt_sock_recvmsg(iocb, sock, msg, len, flags);
 }
 
-static int l2cap_sock_setsockopt_old(struct socket *sock, int optname, char __user *optval, int optlen)
+static int l2cap_sock_setsockopt_old(struct socket *sock, int optname, char __user *optval, unsigned int optlen)
 {
        struct sock *sk = sock->sk;
        struct l2cap_options opts;
@@ -1633,6 +1718,7 @@ static int l2cap_sock_setsockopt_old(struct socket *sock, int optname, char __us
                opts.omtu     = l2cap_pi(sk)->omtu;
                opts.flush_to = l2cap_pi(sk)->flush_to;
                opts.mode     = l2cap_pi(sk)->mode;
+               opts.fcs      = l2cap_pi(sk)->fcs;
 
                len = min_t(unsigned int, sizeof(opts), optlen);
                if (copy_from_user((char *) &opts, optval, len)) {
@@ -1643,6 +1729,7 @@ static int l2cap_sock_setsockopt_old(struct socket *sock, int optname, char __us
                l2cap_pi(sk)->imtu = opts.imtu;
                l2cap_pi(sk)->omtu = opts.omtu;
                l2cap_pi(sk)->mode = opts.mode;
+               l2cap_pi(sk)->fcs  = opts.fcs;
                break;
 
        case L2CAP_LM:
@@ -1671,7 +1758,7 @@ static int l2cap_sock_setsockopt_old(struct socket *sock, int optname, char __us
        return err;
 }
 
-static int l2cap_sock_setsockopt(struct socket *sock, int level, int optname, char __user *optval, int optlen)
+static int l2cap_sock_setsockopt(struct socket *sock, int level, int optname, char __user *optval, unsigned int optlen)
 {
        struct sock *sk = sock->sk;
        struct bt_security sec;
@@ -1756,6 +1843,7 @@ static int l2cap_sock_getsockopt_old(struct socket *sock, int optname, char __us
                opts.omtu     = l2cap_pi(sk)->omtu;
                opts.flush_to = l2cap_pi(sk)->flush_to;
                opts.mode     = l2cap_pi(sk)->mode;
+               opts.fcs      = l2cap_pi(sk)->fcs;
 
                len = min_t(unsigned int, len, sizeof(opts));
                if (copy_to_user(optval, (char *) &opts, len))
@@ -2117,7 +2205,7 @@ static int l2cap_build_conf_req(struct sock *sk, void *data)
 {
        struct l2cap_pinfo *pi = l2cap_pi(sk);
        struct l2cap_conf_req *req = data;
-       struct l2cap_conf_rfc rfc = { .mode = L2CAP_MODE_ERTM };
+       struct l2cap_conf_rfc rfc = { .mode = L2CAP_MODE_BASIC };
        void *ptr = req->data;
 
        BT_DBG("sk %p", sk);
@@ -2154,6 +2242,15 @@ done:
 
                l2cap_add_conf_opt(&ptr, L2CAP_CONF_RFC,
                                        sizeof(rfc), (unsigned long) &rfc);
+
+               if (!(pi->conn->feat_mask & L2CAP_FEAT_FCS))
+                       break;
+
+               if (pi->fcs == L2CAP_FCS_NONE ||
+                               pi->conf_state & L2CAP_CONF_NO_FCS_RECV) {
+                       pi->fcs = L2CAP_FCS_NONE;
+                       l2cap_add_conf_opt(&ptr, L2CAP_CONF_FCS, 1, pi->fcs);
+               }
                break;
 
        case L2CAP_MODE_STREAMING:
@@ -2166,6 +2263,15 @@ done:
 
                l2cap_add_conf_opt(&ptr, L2CAP_CONF_RFC,
                                        sizeof(rfc), (unsigned long) &rfc);
+
+               if (!(pi->conn->feat_mask & L2CAP_FEAT_FCS))
+                       break;
+
+               if (pi->fcs == L2CAP_FCS_NONE ||
+                               pi->conf_state & L2CAP_CONF_NO_FCS_RECV) {
+                       pi->fcs = L2CAP_FCS_NONE;
+                       l2cap_add_conf_opt(&ptr, L2CAP_CONF_FCS, 1, pi->fcs);
+               }
                break;
        }
 
@@ -2217,6 +2323,12 @@ static int l2cap_parse_conf_req(struct sock *sk, void *data)
                                memcpy(&rfc, (void *) val, olen);
                        break;
 
+               case L2CAP_CONF_FCS:
+                       if (val == L2CAP_FCS_NONE)
+                               pi->conf_state |= L2CAP_CONF_NO_FCS_RECV;
+
+                       break;
+
                default:
                        if (hint)
                                break;
@@ -2638,6 +2750,10 @@ static inline int l2cap_config_req(struct l2cap_conn *conn, struct l2cap_cmd_hdr
                goto unlock;
 
        if (l2cap_pi(sk)->conf_state & L2CAP_CONF_INPUT_DONE) {
+               if (!(l2cap_pi(sk)->conf_state & L2CAP_CONF_NO_FCS_RECV)
+                               || l2cap_pi(sk)->fcs != L2CAP_FCS_NONE)
+                       l2cap_pi(sk)->fcs = L2CAP_FCS_CRC16;
+
                sk->sk_state = BT_CONNECTED;
                l2cap_pi(sk)->next_tx_seq = 0;
                l2cap_pi(sk)->expected_ack_seq = 0;
@@ -2649,6 +2765,7 @@ static inline int l2cap_config_req(struct l2cap_conn *conn, struct l2cap_cmd_hdr
                                l2cap_monitor_timeout, (unsigned long) sk);
 
                __skb_queue_head_init(TX_QUEUE(sk));
+               __skb_queue_head_init(SREJ_QUEUE(sk));
                l2cap_chan_ready(sk);
                goto unlock;
        }
@@ -2722,10 +2839,16 @@ static inline int l2cap_config_rsp(struct l2cap_conn *conn, struct l2cap_cmd_hdr
        l2cap_pi(sk)->conf_state |= L2CAP_CONF_INPUT_DONE;
 
        if (l2cap_pi(sk)->conf_state & L2CAP_CONF_OUTPUT_DONE) {
+               if (!(l2cap_pi(sk)->conf_state & L2CAP_CONF_NO_FCS_RECV)
+                               || l2cap_pi(sk)->fcs != L2CAP_FCS_NONE)
+                       l2cap_pi(sk)->fcs = L2CAP_FCS_CRC16;
+
                sk->sk_state = BT_CONNECTED;
                l2cap_pi(sk)->expected_tx_seq = 0;
+               l2cap_pi(sk)->buffer_seq = 0;
                l2cap_pi(sk)->num_to_ack = 0;
                __skb_queue_head_init(TX_QUEUE(sk));
+               __skb_queue_head_init(SREJ_QUEUE(sk));
                l2cap_chan_ready(sk);
        }
 
@@ -2757,6 +2880,7 @@ static inline int l2cap_disconnect_req(struct l2cap_conn *conn, struct l2cap_cmd
        sk->sk_shutdown = SHUTDOWN_MASK;
 
        skb_queue_purge(TX_QUEUE(sk));
+       skb_queue_purge(SREJ_QUEUE(sk));
        del_timer(&l2cap_pi(sk)->retrans_timer);
        del_timer(&l2cap_pi(sk)->monitor_timer);
 
@@ -2783,6 +2907,7 @@ static inline int l2cap_disconnect_rsp(struct l2cap_conn *conn, struct l2cap_cmd
                return 0;
 
        skb_queue_purge(TX_QUEUE(sk));
+       skb_queue_purge(SREJ_QUEUE(sk));
        del_timer(&l2cap_pi(sk)->retrans_timer);
        del_timer(&l2cap_pi(sk)->monitor_timer);
 
@@ -2809,8 +2934,9 @@ static inline int l2cap_information_req(struct l2cap_conn *conn, struct l2cap_cm
                rsp->type   = cpu_to_le16(L2CAP_IT_FEAT_MASK);
                rsp->result = cpu_to_le16(L2CAP_IR_SUCCESS);
                if (enable_ertm)
-                       feat_mask |= L2CAP_FEAT_ERTM | L2CAP_FEAT_STREAMING;
-               put_unaligned(cpu_to_le32(feat_mask), (__le32 *) rsp->data);
+                       feat_mask |= L2CAP_FEAT_ERTM | L2CAP_FEAT_STREAMING
+                                                        | L2CAP_FEAT_FCS;
+               put_unaligned_le32(feat_mask, rsp->data);
                l2cap_send_cmd(conn, cmd->ident,
                                        L2CAP_INFO_RSP, sizeof(buf), buf);
        } else if (type == L2CAP_IT_FIXED_CHAN) {
@@ -2961,6 +3087,49 @@ static inline void l2cap_sig_channel(struct l2cap_conn *conn, struct sk_buff *sk
        kfree_skb(skb);
 }
 
+static int l2cap_check_fcs(struct l2cap_pinfo *pi,  struct sk_buff *skb)
+{
+       u16 our_fcs, rcv_fcs;
+       int hdr_size = L2CAP_HDR_SIZE + 2;
+
+       if (pi->fcs == L2CAP_FCS_CRC16) {
+               skb_trim(skb, skb->len - 2);
+               rcv_fcs = get_unaligned_le16(skb->data + skb->len);
+               our_fcs = crc16(0, skb->data - hdr_size, skb->len + hdr_size);
+
+               if (our_fcs != rcv_fcs)
+                       return -EINVAL;
+       }
+       return 0;
+}
+
+static void l2cap_add_to_srej_queue(struct sock *sk, struct sk_buff *skb, u8 tx_seq, u8 sar)
+{
+       struct sk_buff *next_skb;
+
+       bt_cb(skb)->tx_seq = tx_seq;
+       bt_cb(skb)->sar = sar;
+
+       next_skb = skb_peek(SREJ_QUEUE(sk));
+       if (!next_skb) {
+               __skb_queue_tail(SREJ_QUEUE(sk), skb);
+               return;
+       }
+
+       do {
+               if (bt_cb(next_skb)->tx_seq > tx_seq) {
+                       __skb_queue_before(SREJ_QUEUE(sk), next_skb, skb);
+                       return;
+               }
+
+               if (skb_queue_is_last(SREJ_QUEUE(sk), next_skb))
+                       break;
+
+       } while((next_skb = skb_queue_next(SREJ_QUEUE(sk), next_skb)));
+
+       __skb_queue_tail(SREJ_QUEUE(sk), skb);
+}
+
 static int l2cap_sar_reassembly_sdu(struct sock *sk, struct sk_buff *skb, u16 control)
 {
        struct l2cap_pinfo *pi = l2cap_pi(sk);
@@ -3041,50 +3210,149 @@ static int l2cap_sar_reassembly_sdu(struct sock *sk, struct sk_buff *skb, u16 co
        return err;
 }
 
+static void l2cap_check_srej_gap(struct sock *sk, u8 tx_seq)
+{
+       struct sk_buff *skb;
+       u16 control = 0;
+
+       while((skb = skb_peek(SREJ_QUEUE(sk)))) {
+               if (bt_cb(skb)->tx_seq != tx_seq)
+                       break;
+
+               skb = skb_dequeue(SREJ_QUEUE(sk));
+               control |= bt_cb(skb)->sar << L2CAP_CTRL_SAR_SHIFT;
+               l2cap_sar_reassembly_sdu(sk, skb, control);
+               l2cap_pi(sk)->buffer_seq_srej =
+                       (l2cap_pi(sk)->buffer_seq_srej + 1) % 64;
+               tx_seq++;
+       }
+}
+
+static void l2cap_resend_srejframe(struct sock *sk, u8 tx_seq)
+{
+       struct l2cap_pinfo *pi = l2cap_pi(sk);
+       struct srej_list *l, *tmp;
+       u16 control;
+
+       list_for_each_entry_safe(l,tmp, SREJ_LIST(sk), list) {
+               if (l->tx_seq == tx_seq) {
+                       list_del(&l->list);
+                       kfree(l);
+                       return;
+               }
+               control = L2CAP_SUPER_SELECT_REJECT;
+               control |= l->tx_seq << L2CAP_CTRL_REQSEQ_SHIFT;
+               l2cap_send_sframe(pi, control);
+               list_del(&l->list);
+               list_add_tail(&l->list, SREJ_LIST(sk));
+       }
+}
+
+static void l2cap_send_srejframe(struct sock *sk, u8 tx_seq)
+{
+       struct l2cap_pinfo *pi = l2cap_pi(sk);
+       struct srej_list *new;
+       u16 control;
+
+       while (tx_seq != pi->expected_tx_seq) {
+               control = L2CAP_SUPER_SELECT_REJECT;
+               control |= pi->expected_tx_seq << L2CAP_CTRL_REQSEQ_SHIFT;
+               if (pi->conn_state & L2CAP_CONN_SEND_PBIT) {
+                       control |= L2CAP_CTRL_POLL;
+                       pi->conn_state &= ~L2CAP_CONN_SEND_PBIT;
+               }
+               l2cap_send_sframe(pi, control);
+
+               new = kzalloc(sizeof(struct srej_list), GFP_ATOMIC);
+               new->tx_seq = pi->expected_tx_seq++;
+               list_add_tail(&new->list, SREJ_LIST(sk));
+       }
+       pi->expected_tx_seq++;
+}
+
 static inline int l2cap_data_channel_iframe(struct sock *sk, u16 rx_control, struct sk_buff *skb)
 {
        struct l2cap_pinfo *pi = l2cap_pi(sk);
        u8 tx_seq = __get_txseq(rx_control);
        u16 tx_control = 0;
+       u8 sar = rx_control >> L2CAP_CTRL_SAR_SHIFT;
        int err = 0;
 
        BT_DBG("sk %p rx_control 0x%4.4x len %d", sk, rx_control, skb->len);
 
-       if (tx_seq == pi->expected_tx_seq) {
-               if (pi->conn_state & L2CAP_CONN_UNDER_REJ)
-                       pi->conn_state &= ~L2CAP_CONN_UNDER_REJ;
+       if (tx_seq == pi->expected_tx_seq)
+               goto expected;
 
-               err = l2cap_sar_reassembly_sdu(sk, skb, rx_control);
-               if (err < 0)
-                       return err;
+       if (pi->conn_state & L2CAP_CONN_SREJ_SENT) {
+               struct srej_list *first;
+
+               first = list_first_entry(SREJ_LIST(sk),
+                               struct srej_list, list);
+               if (tx_seq == first->tx_seq) {
+                       l2cap_add_to_srej_queue(sk, skb, tx_seq, sar);
+                       l2cap_check_srej_gap(sk, tx_seq);
+
+                       list_del(&first->list);
+                       kfree(first);
 
-               pi->expected_tx_seq = (pi->expected_tx_seq + 1) % 64;
-               pi->num_to_ack = (pi->num_to_ack + 1) % L2CAP_DEFAULT_NUM_TO_ACK;
-               if (pi->num_to_ack == L2CAP_DEFAULT_NUM_TO_ACK - 1) {
-                       tx_control |= L2CAP_SUPER_RCV_READY;
-                       tx_control |= pi->expected_tx_seq << L2CAP_CTRL_REQSEQ_SHIFT;
-                       goto send;
+                       if (list_empty(SREJ_LIST(sk))) {
+                               pi->buffer_seq = pi->buffer_seq_srej;
+                               pi->conn_state &= ~L2CAP_CONN_SREJ_SENT;
+                       }
+               } else {
+                       struct srej_list *l;
+                       l2cap_add_to_srej_queue(sk, skb, tx_seq, sar);
+
+                       list_for_each_entry(l, SREJ_LIST(sk), list) {
+                               if (l->tx_seq == tx_seq) {
+                                       l2cap_resend_srejframe(sk, tx_seq);
+                                       return 0;
+                               }
+                       }
+                       l2cap_send_srejframe(sk, tx_seq);
                }
        } else {
-               /* Unexpected txSeq. Send a REJ S-frame */
-               kfree_skb(skb);
-               if (!(pi->conn_state & L2CAP_CONN_UNDER_REJ)) {
-                       tx_control |= L2CAP_SUPER_REJECT;
-                       tx_control |= pi->expected_tx_seq << L2CAP_CTRL_REQSEQ_SHIFT;
-                       pi->conn_state |= L2CAP_CONN_UNDER_REJ;
+               pi->conn_state |= L2CAP_CONN_SREJ_SENT;
 
-                       goto send;
-               }
+               INIT_LIST_HEAD(SREJ_LIST(sk));
+               pi->buffer_seq_srej = pi->buffer_seq;
+
+               __skb_queue_head_init(SREJ_QUEUE(sk));
+               l2cap_add_to_srej_queue(sk, skb, tx_seq, sar);
+
+               pi->conn_state |= L2CAP_CONN_SEND_PBIT;
+
+               l2cap_send_srejframe(sk, tx_seq);
        }
        return 0;
 
-send:
-       return l2cap_send_sframe(pi, tx_control);
+expected:
+       pi->expected_tx_seq = (pi->expected_tx_seq + 1) % 64;
+
+       if (pi->conn_state & L2CAP_CONN_SREJ_SENT) {
+               l2cap_add_to_srej_queue(sk, skb, tx_seq, sar);
+               return 0;
+       }
+
+       pi->buffer_seq = (pi->buffer_seq + 1) % 64;
+
+       err = l2cap_sar_reassembly_sdu(sk, skb, rx_control);
+       if (err < 0)
+               return err;
+
+       pi->num_to_ack = (pi->num_to_ack + 1) % L2CAP_DEFAULT_NUM_TO_ACK;
+       if (pi->num_to_ack == L2CAP_DEFAULT_NUM_TO_ACK - 1) {
+               tx_control |= L2CAP_SUPER_RCV_READY;
+               tx_control |= pi->buffer_seq << L2CAP_CTRL_REQSEQ_SHIFT;
+               l2cap_send_sframe(pi, tx_control);
+       }
+       return 0;
 }
 
 static inline int l2cap_data_channel_sframe(struct sock *sk, u16 rx_control, struct sk_buff *skb)
 {
        struct l2cap_pinfo *pi = l2cap_pi(sk);
+       u8 tx_seq = __get_reqseq(rx_control);
 
        BT_DBG("sk %p rx_control 0x%4.4x len %d", sk, rx_control, skb->len);
 
@@ -3092,9 +3360,16 @@ static inline int l2cap_data_channel_sframe(struct sock *sk, u16 rx_control, str
        case L2CAP_SUPER_RCV_READY:
                if (rx_control & L2CAP_CTRL_POLL) {
                        u16 control = L2CAP_CTRL_FINAL;
-                       control |= L2CAP_SUPER_RCV_READY;
+                       control |= L2CAP_SUPER_RCV_READY |
+                               (pi->buffer_seq << L2CAP_CTRL_REQSEQ_SHIFT);
                        l2cap_send_sframe(l2cap_pi(sk), control);
+                       pi->conn_state &= ~L2CAP_CONN_REMOTE_BUSY;
+
                } else if (rx_control & L2CAP_CTRL_FINAL) {
+                       pi->conn_state &= ~L2CAP_CONN_REMOTE_BUSY;
+                       pi->expected_ack_seq = tx_seq;
+                       l2cap_drop_acked_frames(sk);
+
                        if (!(pi->conn_state & L2CAP_CONN_WAIT_F))
                                break;
 
@@ -3104,15 +3379,21 @@ static inline int l2cap_data_channel_sframe(struct sock *sk, u16 rx_control, str
                        if (pi->unacked_frames > 0)
                                __mod_retrans_timer();
                } else {
-                       pi->expected_ack_seq = __get_reqseq(rx_control);
+                       pi->expected_ack_seq = tx_seq;
                        l2cap_drop_acked_frames(sk);
-                       if (pi->unacked_frames > 0)
+
+                       if ((pi->conn_state & L2CAP_CONN_REMOTE_BUSY)
+                                       && (pi->unacked_frames > 0))
                                __mod_retrans_timer();
+
                        l2cap_ertm_send(sk);
+                       pi->conn_state &= ~L2CAP_CONN_REMOTE_BUSY;
                }
                break;
 
        case L2CAP_SUPER_REJECT:
+               pi->conn_state &= ~L2CAP_CONN_REMOTE_BUSY;
+
                pi->expected_ack_seq = __get_reqseq(rx_control);
                l2cap_drop_acked_frames(sk);
 
@@ -3123,8 +3404,44 @@ static inline int l2cap_data_channel_sframe(struct sock *sk, u16 rx_control, str
 
                break;
 
-       case L2CAP_SUPER_RCV_NOT_READY:
        case L2CAP_SUPER_SELECT_REJECT:
+               pi->conn_state &= ~L2CAP_CONN_REMOTE_BUSY;
+
+               if (rx_control & L2CAP_CTRL_POLL) {
+                       l2cap_retransmit_frame(sk, tx_seq);
+                       pi->expected_ack_seq = tx_seq;
+                       l2cap_drop_acked_frames(sk);
+                       l2cap_ertm_send(sk);
+                       if (pi->conn_state & L2CAP_CONN_WAIT_F) {
+                               pi->srej_save_reqseq = tx_seq;
+                               pi->conn_state |= L2CAP_CONN_SREJ_ACT;
+                       }
+               } else if (rx_control & L2CAP_CTRL_FINAL) {
+                       if ((pi->conn_state & L2CAP_CONN_SREJ_ACT) &&
+                                       pi->srej_save_reqseq == tx_seq)
+                               pi->srej_save_reqseq &= ~L2CAP_CONN_SREJ_ACT;
+                       else
+                               l2cap_retransmit_frame(sk, tx_seq);
+               }
+               else {
+                       l2cap_retransmit_frame(sk, tx_seq);
+                       if (pi->conn_state & L2CAP_CONN_WAIT_F) {
+                               pi->srej_save_reqseq = tx_seq;
+                               pi->conn_state |= L2CAP_CONN_SREJ_ACT;
+                       }
+               }
+               break;
+
+       case L2CAP_SUPER_RCV_NOT_READY:
+               pi->conn_state |= L2CAP_CONN_REMOTE_BUSY;
+               pi->expected_ack_seq = tx_seq;
+               l2cap_drop_acked_frames(sk);
+
+               del_timer(&l2cap_pi(sk)->retrans_timer);
+               if (rx_control & L2CAP_CTRL_POLL) {
+                       u16 control = L2CAP_CTRL_FINAL;
+                       l2cap_send_rr_or_rnr(l2cap_pi(sk), control);
+               }
                break;
        }
 
@@ -3174,6 +3491,9 @@ static inline int l2cap_data_channel(struct l2cap_conn *conn, u16 cid, struct sk
                if (__is_sar_start(control))
                        len -= 2;
 
+               if (pi->fcs == L2CAP_FCS_CRC16)
+                       len -= 2;
+
                /*
                 * We can just drop the corrupted I-frame here.
                 * Receiver will miss it and start proper recovery
@@ -3182,6 +3502,9 @@ static inline int l2cap_data_channel(struct l2cap_conn *conn, u16 cid, struct sk
                if (len > L2CAP_DEFAULT_MAX_PDU_SIZE)
                        goto drop;
 
+               if (l2cap_check_fcs(pi, skb))
+                       goto drop;
+
                if (__is_iframe(control))
                        err = l2cap_data_channel_iframe(sk, control, skb);
                else
@@ -3199,9 +3522,15 @@ static inline int l2cap_data_channel(struct l2cap_conn *conn, u16 cid, struct sk
                if (__is_sar_start(control))
                        len -= 2;
 
+               if (pi->fcs == L2CAP_FCS_CRC16)
+                       len -= 2;
+
                if (len > L2CAP_DEFAULT_MAX_PDU_SIZE || __is_sframe(control))
                        goto drop;
 
+               if (l2cap_check_fcs(pi, skb))
+                       goto drop;
+
                tx_seq = __get_txseq(control);
 
                if (pi->expected_tx_seq == tx_seq)
@@ -3279,7 +3608,7 @@ static void l2cap_recv_frame(struct l2cap_conn *conn, struct sk_buff *skb)
                break;
 
        case L2CAP_CID_CONN_LESS:
-               psm = get_unaligned((__le16 *) skb->data);
+               psm = get_unaligned_le16(skb->data);
                skb_pull(skb, 2);
                l2cap_conless_channel(conn, psm, skb);
                break;