[RFC v4 0/3] Disconnect reason in Kernel API

[RFC v4 0/3] Disconnect reason in Kernel API

[Mikel Astiz]

From: Mikel Astiz <mikel.astiz@bmw-carit.de>

This patchset extends the management API to expose the low-level disconnect reason.

v4 integrates the feedback from Marcel, mainly:
- Fix minor coding style issue (patch v4 2/3)
- Remove references to "ACL" in mgmt terminology
- Add MGMT_DEV_DISCONN_UNKNOWN
- Add helper function to translate from HCI error codes to mgmt reason

Updated userland patch to be used for testing purposes will be submitted soon.

>From original patch:

During the BlueZ meeting in Brazil it was proposed to add two more values to this enum: "Connection terminated by local host" and "Connection terminated by remote host". However, after some testing, it seems the result can be quite misleading. Therefore and given that there are no known use-cases that need this information (local vs remote disconnection), these two values have been dropped.

Mikel Astiz (3):
  Bluetooth: Add more HCI error codes
  Bluetooth: Fix minor coding style in hci_event.c
  Bluetooth: mgmt: Add device disconnect reason

 include/net/bluetooth/hci.h      |    3 +++
 include/net/bluetooth/hci_core.h |    2 +-
 include/net/bluetooth/mgmt.h     |    9 +++++++++
 net/bluetooth/hci_event.c        |   32 ++++++++++++++++++++++++++------
 net/bluetooth/mgmt.c             |    9 +++++----
 5 files changed, 44 insertions(+), 11 deletions(-)

-- 
1.7.7.6

[RFC v4 1/3] Bluetooth: Add more HCI error codes

[Mikel Astiz]

From: Mikel Astiz <mikel.astiz@bmw-carit.de>

Add more HCI error codes as defined in the specification.

Signed-off-by: Mikel Astiz <mikel.astiz@bmw-carit.de>
Acked-by: Marcel Holtmann <marcel@holtmann.org>
---
 include/net/bluetooth/hci.h |    3 +++
 1 files changed, 3 insertions(+), 0 deletions(-)

diff --git a/include/net/bluetooth/hci.h b/include/net/bluetooth/hci.h
index 7f19556..7253bdd 100644
--- a/include/net/bluetooth/hci.h
+++ b/include/net/bluetooth/hci.h
@@ -302,8 +302,11 @@ enum {
 
 /* ---- HCI Error Codes ---- */
 #define HCI_ERROR_AUTH_FAILURE		0x05
+#define HCI_ERROR_CONNECTION_TIMEOUT	0x08
 #define HCI_ERROR_REJ_BAD_ADDR		0x0f
 #define HCI_ERROR_REMOTE_USER_TERM	0x13
+#define HCI_ERROR_REMOTE_LOW_RESOURCES	0x14
+#define HCI_ERROR_REMOTE_POWER_OFF	0x15
 #define HCI_ERROR_LOCAL_HOST_TERM	0x16
 #define HCI_ERROR_PAIRING_NOT_ALLOWED	0x18
 
-- 
1.7.7.6

[RFC v4 2/3] Bluetooth: Fix minor coding style in hci_event.c

[Mikel Astiz]

From: Mikel Astiz <mikel.astiz@bmw-carit.de>

Replace the status checks with the short form of the boolean expression.

Signed-off-by: Mikel Astiz <mikel.astiz@bmw-carit.de>
---
 net/bluetooth/hci_event.c |    8 ++++----
 1 files changed, 4 insertions(+), 4 deletions(-)

diff --git a/net/bluetooth/hci_event.c b/net/bluetooth/hci_event.c
index 0386e1e..32fcc74 100644
--- a/net/bluetooth/hci_event.c
+++ b/net/bluetooth/hci_event.c
@@ -303,7 +303,7 @@ static void hci_cc_write_scan_enable(struct hci_dev *hdev, struct sk_buff *skb)
 
 	hci_dev_lock(hdev);
 
-	if (status != 0) {
+	if (status) {
 		mgmt_write_scan_failed(hdev, param, status);
 		hdev->discov_timeout = 0;
 		goto done;
@@ -925,7 +925,7 @@ static void hci_cc_pin_code_reply(struct hci_dev *hdev, struct sk_buff *skb)
 	if (test_bit(HCI_MGMT, &hdev->dev_flags))
 		mgmt_pin_code_reply_complete(hdev, &rp->bdaddr, rp->status);
 
-	if (rp->status != 0)
+	if (rp->status)
 		goto unlock;
 
 	cp = hci_sent_cmd_data(hdev, HCI_OP_PIN_CODE_REPLY);
@@ -1906,7 +1906,7 @@ static void hci_disconn_complete_evt(struct hci_dev *hdev, struct sk_buff *skb)
 
 	if (test_and_clear_bit(HCI_CONN_MGMT_CONNECTED, &conn->flags) &&
 	    (conn->type == ACL_LINK || conn->type == LE_LINK)) {
-		if (ev->status != 0)
+		if (ev->status)
 			mgmt_disconnect_failed(hdev, &conn->dst, conn->type,
 					       conn->dst_type, ev->status);
 		else
@@ -3275,7 +3275,7 @@ static void hci_simple_pair_complete_evt(struct hci_dev *hdev,
 	 * initiated the authentication. A traditional auth_complete
 	 * event gets always produced as initiator and is also mapped to
 	 * the mgmt_auth_failed event */
-	if (!test_bit(HCI_CONN_AUTH_PEND, &conn->flags) && ev->status != 0)
+	if (!test_bit(HCI_CONN_AUTH_PEND, &conn->flags) && ev->status)
 		mgmt_auth_failed(hdev, &conn->dst, conn->type, conn->dst_type,
 				 ev->status);
 
-- 
1.7.7.6

Re: [RFC v4 2/3] Bluetooth: Fix minor coding style in hci_event.c

[Marcel Holtmann]

Hi Mikel,

> Replace the status checks with the short form of the boolean expression.
> 
> Signed-off-by: Mikel Astiz <mikel.astiz@bmw-carit.de>
> ---
>  net/bluetooth/hci_event.c |    8 ++++----
>  1 files changed, 4 insertions(+), 4 deletions(-)

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

Regards

Marcel

[RFC v4 3/3] Bluetooth: mgmt: Add device disconnect reason

[Mikel Astiz]

From: Mikel Astiz <mikel.astiz@bmw-carit.de>

MGMT_EV_DEVICE_DISCONNECTED will now expose the disconnection reason to
userland, distinguishing four possible values:

	0x00	Reason not known or unspecified
	0x01	Connection timeout
	0x02	Connection terminated by local host
	0x03	Connection terminated by remote host

Note that the local/remote distinction just determines which side
terminated the low-level connection, regardless of the disconnection of
the higher-level profiles.

This can sometimes be misleading and thus must be used with care. For
example, some hardware combinations would report a locally initiated
disconnection even if the user turned Bluetooth off in the remote side.

Signed-off-by: Mikel Astiz <mikel.astiz@bmw-carit.de>
---
 include/net/bluetooth/hci_core.h |    2 +-
 include/net/bluetooth/mgmt.h     |    9 +++++++++
 net/bluetooth/hci_event.c        |   26 +++++++++++++++++++++++---
 net/bluetooth/mgmt.c             |    9 +++++----
 4 files changed, 38 insertions(+), 8 deletions(-)

diff --git a/include/net/bluetooth/hci_core.h b/include/net/bluetooth/hci_core.h
index 41d9439..4fb0323 100644
--- a/include/net/bluetooth/hci_core.h
+++ b/include/net/bluetooth/hci_core.h
@@ -1004,7 +1004,7 @@ int mgmt_device_connected(struct hci_dev *hdev, bdaddr_t *bdaddr, u8 link_type,
 			  u8 addr_type, u32 flags, u8 *name, u8 name_len,
 			  u8 *dev_class);
 int mgmt_device_disconnected(struct hci_dev *hdev, bdaddr_t *bdaddr,
-			     u8 link_type, u8 addr_type);
+			     u8 link_type, u8 addr_type, u8 reason);
 int mgmt_disconnect_failed(struct hci_dev *hdev, bdaddr_t *bdaddr,
 			   u8 link_type, u8 addr_type, u8 status);
 int mgmt_connect_failed(struct hci_dev *hdev, bdaddr_t *bdaddr, u8 link_type,
diff --git a/include/net/bluetooth/mgmt.h b/include/net/bluetooth/mgmt.h
index 4348ee8..1b48eff 100644
--- a/include/net/bluetooth/mgmt.h
+++ b/include/net/bluetooth/mgmt.h
@@ -405,7 +405,16 @@ struct mgmt_ev_device_connected {
 	__u8	eir[0];
 } __packed;
 
+#define MGMT_DEV_DISCONN_UNKNOWN	0x00
+#define MGMT_DEV_DISCONN_TIMEOUT	0x01
+#define MGMT_DEV_DISCONN_LOCAL_HOST	0x02
+#define MGMT_DEV_DISCONN_REMOTE		0x03
+
 #define MGMT_EV_DEVICE_DISCONNECTED	0x000C
+struct mgmt_ev_device_disconnected {
+	struct mgmt_addr_info addr;
+	__u8	reason;
+} __packed;
 
 #define MGMT_EV_CONNECT_FAILED		0x000D
 struct mgmt_ev_connect_failed {
diff --git a/net/bluetooth/hci_event.c b/net/bluetooth/hci_event.c
index 32fcc74..6e02c93 100644
--- a/net/bluetooth/hci_event.c
+++ b/net/bluetooth/hci_event.c
@@ -29,6 +29,7 @@
 
 #include <net/bluetooth/bluetooth.h>
 #include <net/bluetooth/hci_core.h>
+#include <net/bluetooth/mgmt.h>
 
 /* Handle HCI Event packets */
 
@@ -1888,6 +1889,22 @@ static void hci_conn_request_evt(struct hci_dev *hdev, struct sk_buff *skb)
 	}
 }
 
+static u8 hci_to_mgmt_reason(u8 err)
+{
+	switch (err) {
+	case HCI_ERROR_CONNECTION_TIMEOUT:
+		return MGMT_DEV_DISCONN_TIMEOUT;
+	case HCI_ERROR_REMOTE_USER_TERM:
+	case HCI_ERROR_REMOTE_LOW_RESOURCES:
+	case HCI_ERROR_REMOTE_POWER_OFF:
+		return MGMT_DEV_DISCONN_REMOTE;
+	case HCI_ERROR_LOCAL_HOST_TERM:
+		return MGMT_DEV_DISCONN_LOCAL_HOST;
+	default:
+		return MGMT_DEV_DISCONN_UNKNOWN;
+	}
+}
+
 static void hci_disconn_complete_evt(struct hci_dev *hdev, struct sk_buff *skb)
 {
 	struct hci_ev_disconn_complete *ev = (void *) skb->data;
@@ -1906,12 +1923,15 @@ static void hci_disconn_complete_evt(struct hci_dev *hdev, struct sk_buff *skb)
 
 	if (test_and_clear_bit(HCI_CONN_MGMT_CONNECTED, &conn->flags) &&
 	    (conn->type == ACL_LINK || conn->type == LE_LINK)) {
-		if (ev->status)
+		if (ev->status) {
 			mgmt_disconnect_failed(hdev, &conn->dst, conn->type,
 					       conn->dst_type, ev->status);
-		else
+		} else {
+			u8 reason = hci_to_mgmt_reason(ev->reason);
+
 			mgmt_device_disconnected(hdev, &conn->dst, conn->type,
-						 conn->dst_type);
+						 conn->dst_type, reason);
+		}
 	}
 
 	if (ev->status == 0) {
diff --git a/net/bluetooth/mgmt.c b/net/bluetooth/mgmt.c
index a3329cb..05d4b83 100644
--- a/net/bluetooth/mgmt.c
+++ b/net/bluetooth/mgmt.c
@@ -3077,16 +3077,17 @@ static void unpair_device_rsp(struct pending_cmd *cmd, void *data)
 }
 
 int mgmt_device_disconnected(struct hci_dev *hdev, bdaddr_t *bdaddr,
-			     u8 link_type, u8 addr_type)
+			     u8 link_type, u8 addr_type, u8 reason)
 {
-	struct mgmt_addr_info ev;
+	struct mgmt_ev_device_disconnected ev;
 	struct sock *sk = NULL;
 	int err;
 
 	mgmt_pending_foreach(MGMT_OP_DISCONNECT, hdev, disconnect_rsp, &sk);
 
-	bacpy(&ev.bdaddr, bdaddr);
-	ev.type = link_to_bdaddr(link_type, addr_type);
+	bacpy(&ev.addr.bdaddr, bdaddr);
+	ev.addr.type = link_to_bdaddr(link_type, addr_type);
+	ev.reason = reason;
 
 	err = mgmt_event(MGMT_EV_DEVICE_DISCONNECTED, hdev, &ev, sizeof(ev),
 			 sk);
-- 
1.7.7.6

Re: [RFC v4 3/3] Bluetooth: mgmt: Add device disconnect reason

[Marcel Holtmann]

Hi Mikel,

> MGMT_EV_DEVICE_DISCONNECTED will now expose the disconnection reason to
> userland, distinguishing four possible values:
> 
> 	0x00	Reason not known or unspecified
> 	0x01	Connection timeout
> 	0x02	Connection terminated by local host
> 	0x03	Connection terminated by remote host
> 
> Note that the local/remote distinction just determines which side
> terminated the low-level connection, regardless of the disconnection of
> the higher-level profiles.
> 
> This can sometimes be misleading and thus must be used with care. For
> example, some hardware combinations would report a locally initiated
> disconnection even if the user turned Bluetooth off in the remote side.
> 
> Signed-off-by: Mikel Astiz <mikel.astiz@bmw-carit.de>
> ---
>  include/net/bluetooth/hci_core.h |    2 +-
>  include/net/bluetooth/mgmt.h     |    9 +++++++++
>  net/bluetooth/hci_event.c        |   26 +++++++++++++++++++++++---
>  net/bluetooth/mgmt.c             |    9 +++++----
>  4 files changed, 38 insertions(+), 8 deletions(-)

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

Regards

Marcel

Re: [RFC v4 3/3] Bluetooth: mgmt: Add device disconnect reason

[Gustavo Padovan]

Hi Mikel,

* Mikel Astiz <mikel.astiz.oss@gmail.com> [2012-08-09 09:52:30 +0200]:

> From: Mikel Astiz <mikel.astiz@bmw-carit.de>
> 
> MGMT_EV_DEVICE_DISCONNECTED will now expose the disconnection reason to
> userland, distinguishing four possible values:
> 
> 	0x00	Reason not known or unspecified
> 	0x01	Connection timeout
> 	0x02	Connection terminated by local host
> 	0x03	Connection terminated by remote host
> 
> Note that the local/remote distinction just determines which side
> terminated the low-level connection, regardless of the disconnection of
> the higher-level profiles.
> 
> This can sometimes be misleading and thus must be used with care. For
> example, some hardware combinations would report a locally initiated
> disconnection even if the user turned Bluetooth off in the remote side.
> 
> Signed-off-by: Mikel Astiz <mikel.astiz@bmw-carit.de>
> ---
>  include/net/bluetooth/hci_core.h |    2 +-
>  include/net/bluetooth/mgmt.h     |    9 +++++++++
>  net/bluetooth/hci_event.c        |   26 +++++++++++++++++++++++---
>  net/bluetooth/mgmt.c             |    9 +++++----
>  4 files changed, 38 insertions(+), 8 deletions(-)

All 3 patches have been applied to bluetooth-next. Thanks.

	Gustavo