Hi,
On Wed, Nov 10, 2010 at 5:11 PM, <johan.hedberg@xxxxxxxxx> wrote:
> From: Johan Hedberg <johan.hedberg@xxxxxxxxx>
>
> In Bluetooth there are no automatic updates of remote device names when
> they get changed on the remote side. Instead, it is a good idea to do a
> manual name request when a new connection gets created (for whatever
> reason) since at this point it is very cheap (no costly baseband
> connection creation needed just for the sake of the name request).
>
> So far userspace has been responsible for this extra name request but
> tighter control is needed in order not to flood Bluetooth controllers
> with two many commands during connection creation. It has been shown
> that some controllers simply fail to function correctly if they get too
> many (almost) simultaneous commands during connection creation. The
> simplest way to acheive better control of these commands is to move
> their sending completely to the kernel side.
>
> This patch inserts name requests into the sequence of events that the
> kernel performs during connection creation. It does this after the
> remote features have been successfully requested and before any pending
> authentication requests are performed. The code will work sub-optimally
> with userspace versions that still do the name requesting themselves (it
> shouldn't break anything though) so it is recommended to combine this
> with a userspace software version that doesn't have automated name
> requests.
>
> Signed-off-by: Johan Hedberg <johan.hedberg@xxxxxxxxx>
> ---
> net/bluetooth/hci_event.c | 74 ++++++++++++++++++++++++++++++++++----------
> 1 files changed, 57 insertions(+), 17 deletions(-)
>
> diff --git a/net/bluetooth/hci_event.c b/net/bluetooth/hci_event.c
> index 45569f2..cef970f 100644
> --- a/net/bluetooth/hci_event.c
> +++ b/net/bluetooth/hci_event.c
> @@ -677,9 +677,8 @@ static void hci_cs_set_conn_encrypt(struct hci_dev *hdev, __u8 status)
> hci_dev_unlock(hdev);
> }
>
> -static int request_outgoing_auth(struct hci_dev *hdev, bdaddr_t *bdaddr)
> +static int outgoing_auth_needed(struct hci_dev *hdev, bdaddr_t *bdaddr)
> {
> - struct hci_cp_auth_requested cp;
> struct hci_conn *conn;
>
> conn = hci_conn_hash_lookup_ba(hdev, ACL_LINK, bdaddr);
> @@ -698,15 +697,43 @@ static int request_outgoing_auth(struct hci_dev *hdev, bdaddr_t *bdaddr)
> conn->sec_level != BT_SECURITY_HIGH)
> return 0;
>
> - cp.handle = __cpu_to_le16(conn->handle);
> - hci_send_cmd(hdev, HCI_OP_AUTH_REQUESTED, sizeof(cp), &cp);
> -
> return 1;
> }
>
> +static int request_auth(struct hci_dev *hdev, bdaddr_t *bdaddr)
> +{
> + struct hci_cp_auth_requested cp;
> + struct hci_conn *conn;
> +
> + conn = hci_conn_hash_lookup_ba(hdev, ACL_LINK, bdaddr);
> + if (!conn)
> + return -ENOTCONN;
> +
> + cp.handle = __cpu_to_le16(conn->handle);
> + return hci_send_cmd(hdev, HCI_OP_AUTH_REQUESTED, sizeof(cp), &cp);
> +}
> +
> static void hci_cs_remote_name_req(struct hci_dev *hdev, __u8 status)
> {
> + struct hci_cp_remote_name_req *cp;
> +
> BT_DBG("%s status 0x%x", hdev->name, status);
> +
> + /* If successful wait for the name req complete event before
> + * checking for the need to do authentication */
> + if (!status)
> + return;
> +
> + cp = hci_sent_cmd_data(hdev, HCI_OP_REMOTE_NAME_REQ);
> + if (!cp)
> + return;
> +
> + hci_dev_lock(hdev);
> +
> + if (outgoing_auth_needed(hdev, &cp->bdaddr))
> + request_auth(hdev, &cp->bdaddr);
> +
> + hci_dev_unlock(hdev);
> }
>
> static void hci_cs_read_remote_features(struct hci_dev *hdev, __u8 status)
> @@ -1117,9 +1144,18 @@ static inline void hci_auth_complete_evt(struct hci_dev *hdev, struct sk_buff *s
>
> static inline void hci_remote_name_evt(struct hci_dev *hdev, struct sk_buff *skb)
> {
> + struct hci_ev_remote_name *ev = (void *) skb->data;
> +
> BT_DBG("%s", hdev->name);
>
> hci_conn_check_pending(hdev);
> +
> + hci_dev_lock(hdev);
> +
> + if (outgoing_auth_needed(hdev, &ev->bdaddr))
> + request_auth(hdev, &ev->bdaddr);
> +
> + hci_dev_unlock(hdev);
> }
>
> static inline void hci_encrypt_change_evt(struct hci_dev *hdev, struct sk_buff *skb)
> @@ -1183,7 +1219,6 @@ static inline void hci_remote_features_evt(struct hci_dev *hdev, struct sk_buff
> {
> struct hci_ev_remote_features *ev = (void *) skb->data;
> struct hci_conn *conn;
> - int auth_requested;
>
> BT_DBG("%s status %d", hdev->name, ev->status);
>
> @@ -1208,12 +1243,15 @@ static inline void hci_remote_features_evt(struct hci_dev *hdev, struct sk_buff
> goto unlock;
> }
>
> - if (!ev->status)
> - auth_requested = request_outgoing_auth(hdev, &conn->dst);
> - else
> - auth_requested = 0;
> + if (!ev->status) {
> + struct hci_cp_remote_name_req cp;
> + memset(&cp, 0, sizeof(cp));
> + bacpy(&cp.bdaddr, &conn->dst);
> + cp.pscan_rep_mode = 0x02;
> + hci_send_cmd(hdev, HCI_OP_REMOTE_NAME_REQ, sizeof(cp), &cp);
> + }
>
> - if (!auth_requested) {
> + if (!outgoing_auth_needed(hdev, &conn->dst)) {
> conn->state = BT_CONNECTED;
> hci_proto_connect_cfm(conn, ev->status);
> hci_conn_put(conn);
> @@ -1671,7 +1709,6 @@ static inline void hci_remote_ext_features_evt(struct hci_dev *hdev, struct sk_b
> {
> struct hci_ev_remote_ext_features *ev = (void *) skb->data;
> struct hci_conn *conn;
> - int auth_requested;
>
> BT_DBG("%s", hdev->name);
>
> @@ -1693,12 +1730,15 @@ static inline void hci_remote_ext_features_evt(struct hci_dev *hdev, struct sk_b
> if (conn->state != BT_CONFIG)
> goto unlock;
>
> - if (!ev->status)
> - auth_requested = request_outgoing_auth(hdev, &conn->dst);
> - else
> - auth_requested = 0;
> + if (!ev->status) {
> + struct hci_cp_remote_name_req cp;
> + memset(&cp, 0, sizeof(cp));
> + bacpy(&cp.bdaddr, &conn->dst);
> + cp.pscan_rep_mode = 0x02;
> + hci_send_cmd(hdev, HCI_OP_REMOTE_NAME_REQ, sizeof(cp), &cp);
> + }
>
> - if (!auth_requested) {
> + if (!outgoing_auth_needed(hdev, &conn->dst)) {
> conn->state = BT_CONNECTED;
> hci_proto_connect_cfm(conn, ev->status);
> hci_conn_put(conn);
> --
> 1.7.2.3
>
> --
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>
Acked-by: Luiz Augusto von Dentz <luiz.dentz-von@xxxxxxxxx>
--
Luiz Augusto von Dentz
Computer Engineer
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