Bluetooth: Add support for sending MGMT open and close to monitor

This sends new notifications to the monitor support whenever a
management channel has been opened or closed. This allows tracing of
control channels really easily.

Signed-off-by: Marcel Holtmann <marcel@holtmann.org>
Signed-off-by: Johan Hedberg <johan.hedberg@intel.com>

1 files changed, 95 insertions, 0 deletions

diff --git a/net/bluetooth/hci_sock.c b/net/bluetooth/hci_sock.c
index 4dce6dfdb0f2..2d8725006838 100644
--- a/net/bluetooth/hci_sock.c
+++ b/net/bluetooth/hci_sock.c
@@ -394,6 +394,59 @@ static struct sk_buff *create_monitor_event(struct hci_dev *hdev, int event)
         return skb;
 }
 
+static struct sk_buff *create_monitor_ctrl_open(struct sock *sk)
+{
+        struct hci_mon_hdr *hdr;
+        struct sk_buff *skb;
+        u16 format = 0x0002;
+        u8 ver[3];
+        u32 flags;
+
+        skb = bt_skb_alloc(14 + TASK_COMM_LEN , GFP_ATOMIC);
+        if (!skb)
+                return NULL;
+
+        mgmt_fill_version_info(ver);
+        flags = hci_sock_test_flag(sk, HCI_SOCK_TRUSTED) ? 0x1 : 0x0;
+
+        put_unaligned_le32(hci_pi(sk)->cookie, skb_put(skb, 4));
+        put_unaligned_le16(format, skb_put(skb, 2));
+        memcpy(skb_put(skb, sizeof(ver)), ver, sizeof(ver));
+        put_unaligned_le32(flags, skb_put(skb, 4));
+        *skb_put(skb, 1) = TASK_COMM_LEN;
+        memcpy(skb_put(skb, TASK_COMM_LEN), hci_pi(sk)->comm, TASK_COMM_LEN);
+
+        __net_timestamp(skb);
+
+        hdr = (void *)skb_push(skb, HCI_MON_HDR_SIZE);
+        hdr->opcode = cpu_to_le16(HCI_MON_CTRL_OPEN);
+        hdr->index = cpu_to_le16(HCI_DEV_NONE);
+        hdr->len = cpu_to_le16(skb->len - HCI_MON_HDR_SIZE);
+
+        return skb;
+}
+
+static struct sk_buff *create_monitor_ctrl_close(struct sock *sk)
+{
+        struct hci_mon_hdr *hdr;
+        struct sk_buff *skb;
+
+        skb = bt_skb_alloc(4, GFP_ATOMIC);
+        if (!skb)
+                return NULL;
+
+        put_unaligned_le32(hci_pi(sk)->cookie, skb_put(skb, 4));
+
+        __net_timestamp(skb);
+
+        hdr = (void *)skb_push(skb, HCI_MON_HDR_SIZE);
+        hdr->opcode = cpu_to_le16(HCI_MON_CTRL_CLOSE);
+        hdr->index = cpu_to_le16(HCI_DEV_NONE);
+        hdr->len = cpu_to_le16(skb->len - HCI_MON_HDR_SIZE);
+
+        return skb;
+}
+
 static void __printf(2, 3)
 send_monitor_note(struct sock *sk, const char *fmt, ...)
 {
@@ -468,6 +521,29 @@ static void send_monitor_replay(struct sock *sk)
         read_unlock(&hci_dev_list_lock);
 }
 
+static void send_monitor_control_replay(struct sock *mon_sk)
+{
+        struct sock *sk;
+
+        read_lock(&hci_sk_list.lock);
+
+        sk_for_each(sk, &hci_sk_list.head) {
+                struct sk_buff *skb;
+
+                if (hci_pi(sk)->channel != HCI_CHANNEL_CONTROL)
+                        continue;
+
+                skb = create_monitor_ctrl_open(sk);
+                if (!skb)
+                        continue;
+
+                if (sock_queue_rcv_skb(mon_sk, skb))
+                        kfree_skb(skb);
+        }
+
+        read_unlock(&hci_sk_list.lock);
+}
+
 /* Generate internal stack event */
 static void hci_si_event(struct hci_dev *hdev, int type, int dlen, void *data)
 {
@@ -595,6 +671,7 @@ static int hci_sock_release(struct socket *sock)
 {
         struct sock *sk = sock->sk;
         struct hci_dev *hdev;
+        struct sk_buff *skb;
         int id;
 
         BT_DBG("sock %p sk %p", sock, sk);
@@ -611,6 +688,14 @@ static int hci_sock_release(struct socket *sock)
         case HCI_CHANNEL_CONTROL:
                 id = hci_pi(sk)->cookie;
 
+                /* Send event to monitor */
+                skb = create_monitor_ctrl_close(sk);
+                if (skb) {
+                        hci_send_to_channel(HCI_CHANNEL_MONITOR, skb,
+                                            HCI_SOCK_TRUSTED, NULL);
+                        kfree_skb(skb);
+                }
+
                 hci_pi(sk)->cookie = 0xffffffff;
                 ida_simple_remove(&sock_cookie_ida, id);
                 break;
@@ -931,6 +1016,7 @@ static int hci_sock_bind(struct socket *sock, struct sockaddr *addr,
                 send_monitor_note(sk, "Bluetooth subsystem version %s",
                                   BT_SUBSYS_VERSION);
                 send_monitor_replay(sk);
+                send_monitor_control_replay(sk);
 
                 atomic_inc(&monitor_promisc);
                 break;
@@ -977,6 +1063,7 @@ static int hci_sock_bind(struct socket *sock, struct sockaddr *addr,
                  * are changes to settings, class of device, name etc.
                  */
                 if (haddr.hci_channel == HCI_CHANNEL_CONTROL) {
+                        struct sk_buff *skb;
                         int id;
 
                         id = ida_simple_get(&sock_cookie_ida, 1, 0, GFP_KERNEL);
@@ -986,6 +1073,14 @@ static int hci_sock_bind(struct socket *sock, struct sockaddr *addr,
                         hci_pi(sk)->cookie = id;
                         get_task_comm(hci_pi(sk)->comm, current);
 
+                        /* Send event to monitor */
+                        skb = create_monitor_ctrl_open(sk);
+                        if (skb) {
+                                hci_send_to_channel(HCI_CHANNEL_MONITOR, skb,
+                                                    HCI_SOCK_TRUSTED, NULL);
+                                kfree_skb(skb);
+                        }
+
                         hci_sock_set_flag(sk, HCI_MGMT_INDEX_EVENTS);
                         hci_sock_set_flag(sk, HCI_MGMT_UNCONF_INDEX_EVENTS);
                         hci_sock_set_flag(sk, HCI_MGMT_GENERIC_EVENTS);