[PATCH 1/3] Bluetooth: Fix local name in scan rsp

[PATCH 1/3] Bluetooth: Fix local name in scan rsp

[Michał Narajowski]

Use complete name if it fits. If not and there is short name
check if it fits. If not then use shortened name as prefix
of complete name.

Signed-off-by: Michał Narajowski <michal.narajowski@codecoup.pl>
---
 net/bluetooth/hci_request.c | 47 +++++++++++++++++++++++++++++++++------------
 1 file changed, 35 insertions(+), 12 deletions(-)

diff --git a/net/bluetooth/hci_request.c b/net/bluetooth/hci_request.c
index c813568..fd6406d 100644
--- a/net/bluetooth/hci_request.c
+++ b/net/bluetooth/hci_request.c
@@ -973,25 +973,48 @@ void __hci_req_enable_advertising(struct hci_request *req)
 
 static u8 append_local_name(struct hci_dev *hdev, u8 *ptr, u8 ad_len)
 {
-	size_t name_len;
+	size_t complete_len;
+	size_t short_len;
 	int max_len;
 
 	max_len = HCI_MAX_AD_LENGTH - ad_len - 2;
-	name_len = strlen(hdev->dev_name);
-	if (name_len > 0 && max_len > 0) {
+	complete_len = strlen(hdev->dev_name);
+	short_len = strlen(hdev->short_name);
 
-		if (name_len > max_len) {
-			name_len = max_len;
-			ptr[1] = EIR_NAME_SHORT;
-		} else
-			ptr[1] = EIR_NAME_COMPLETE;
+	/* no space left for name */
+	if (max_len < 1)
+		return ad_len;
 
-		ptr[0] = name_len + 1;
+	/* no name set */
+	if (!complete_len)
+		return ad_len;
 
-		memcpy(ptr + 2, hdev->dev_name, name_len);
+	/* complete name fits and is eq to max short name len or smaller */
+	if (complete_len <= max_len &&
+	    complete_len <= HCI_MAX_SHORT_NAME_LENGTH) {
+		ptr[0] = complete_len + 1;
+		ptr[1] = EIR_NAME_COMPLETE;
+		memcpy(ptr + 2, hdev->dev_name, complete_len);
 
-		ad_len += (name_len + 2);
-		ptr += (name_len + 2);
+		return ad_len + complete_len + 2;
+	}
+
+	/* short name set and fits */
+	if (short_len && short_len <= max_len) {
+		ptr[0] = short_len + 1;
+		ptr[1] = EIR_NAME_SHORT;
+		memcpy(ptr + 2, hdev->short_name, short_len);
+
+		return ad_len + short_len + 2;
+	}
+
+	/* no short name set so shorten complete name */
+	if (!short_len) {
+		ptr[0] = max_len + 1;
+		ptr[1] = EIR_NAME_SHORT;
+		memcpy(ptr + 2, hdev->dev_name, max_len);
+
+		return ad_len + max_len + 2;
 	}
 
 	return ad_len;
-- 
2.7.4

[PATCH 2/3] Bluetooth: Add appearance to default scan rsp data

[Michał Narajowski]

Add appearance value to beginning of scan rsp data for
default advertising instance if the value is not 0.

Signed-off-by: Michał Narajowski <michal.narajowski@codecoup.pl>
---
 net/bluetooth/hci_request.c | 11 ++++++++++-
 1 file changed, 10 insertions(+), 1 deletion(-)

diff --git a/net/bluetooth/hci_request.c b/net/bluetooth/hci_request.c
index fd6406d..3c44c54 100644
--- a/net/bluetooth/hci_request.c
+++ b/net/bluetooth/hci_request.c
@@ -1022,7 +1022,16 @@ static u8 append_local_name(struct hci_dev *hdev, u8 *ptr, u8 ad_len)
 
 static u8 create_default_scan_rsp_data(struct hci_dev *hdev, u8 *ptr)
 {
-	return append_local_name(hdev, ptr, 0);
+	u8 scan_rsp_len = 0;
+
+	if (hdev->appearance) {
+		ptr[0] = 3;
+		ptr[1] = EIR_APPEARANCE;
+		put_unaligned_le16(hdev->appearance, ptr + 2);
+		scan_rsp_len += 4;
+	}
+
+	return append_local_name(hdev, ptr + scan_rsp_len, scan_rsp_len);
 }
 
 static u8 create_instance_scan_rsp_data(struct hci_dev *hdev, u8 instance,
-- 
2.7.4

[PATCH 3/3] Bluetooth: Refactor append name and appearance

[Michał Narajowski]

Use eir_append_data to remove code duplication.

Signed-off-by: Michał Narajowski <michal.narajowski@codecoup.pl>
---
 net/bluetooth/hci_request.c | 44 +++++++++++++++-----------------------------
 net/bluetooth/hci_request.h | 23 +++++++++++++++++++++++
 net/bluetooth/mgmt.c        | 21 ---------------------
 3 files changed, 38 insertions(+), 50 deletions(-)

diff --git a/net/bluetooth/hci_request.c b/net/bluetooth/hci_request.c
index 3c44c54..e228842 100644
--- a/net/bluetooth/hci_request.c
+++ b/net/bluetooth/hci_request.c
@@ -21,8 +21,6 @@
    SOFTWARE IS DISCLAIMED.
 */
 
-#include <asm/unaligned.h>
-
 #include <net/bluetooth/bluetooth.h>
 #include <net/bluetooth/hci_core.h>
 #include <net/bluetooth/mgmt.h>
@@ -992,46 +990,39 @@ static u8 append_local_name(struct hci_dev *hdev, u8 *ptr, u8 ad_len)
 	/* complete name fits and is eq to max short name len or smaller */
 	if (complete_len <= max_len &&
 	    complete_len <= HCI_MAX_SHORT_NAME_LENGTH) {
-		ptr[0] = complete_len + 1;
-		ptr[1] = EIR_NAME_COMPLETE;
-		memcpy(ptr + 2, hdev->dev_name, complete_len);
-
-		return ad_len + complete_len + 2;
+		return eir_append_data(ptr, ad_len, EIR_NAME_COMPLETE,
+				       hdev->dev_name, complete_len);
 	}
 
 	/* short name set and fits */
 	if (short_len && short_len <= max_len) {
-		ptr[0] = short_len + 1;
-		ptr[1] = EIR_NAME_SHORT;
-		memcpy(ptr + 2, hdev->short_name, short_len);
-
-		return ad_len + short_len + 2;
+		return eir_append_data(ptr, ad_len, EIR_NAME_SHORT,
+				       hdev->short_name, short_len);
 	}
 
 	/* no short name set so shorten complete name */
 	if (!short_len) {
-		ptr[0] = max_len + 1;
-		ptr[1] = EIR_NAME_SHORT;
-		memcpy(ptr + 2, hdev->dev_name, max_len);
-
-		return ad_len + max_len + 2;
+		return eir_append_data(ptr, ad_len, EIR_NAME_SHORT,
+				       hdev->dev_name, max_len);
 	}
 
 	return ad_len;
 }
 
+static u8 append_appearance(struct hci_dev *hdev, u8 *ptr, u8 ad_len)
+{
+	return eir_append_le16(ptr, ad_len, EIR_APPEARANCE, hdev->appearance);
+}
+
 static u8 create_default_scan_rsp_data(struct hci_dev *hdev, u8 *ptr)
 {
 	u8 scan_rsp_len = 0;
 
 	if (hdev->appearance) {
-		ptr[0] = 3;
-		ptr[1] = EIR_APPEARANCE;
-		put_unaligned_le16(hdev->appearance, ptr + 2);
-		scan_rsp_len += 4;
+		scan_rsp_len = append_appearance(hdev, ptr, scan_rsp_len);
 	}
 
-	return append_local_name(hdev, ptr + scan_rsp_len, scan_rsp_len);
+	return append_local_name(hdev, ptr, scan_rsp_len);
 }
 
 static u8 create_instance_scan_rsp_data(struct hci_dev *hdev, u8 instance,
@@ -1048,18 +1039,13 @@ static u8 create_instance_scan_rsp_data(struct hci_dev *hdev, u8 instance,
 	instance_flags = adv_instance->flags;
 
 	if ((instance_flags & MGMT_ADV_FLAG_APPEARANCE) && hdev->appearance) {
-		ptr[0] = 3;
-		ptr[1] = EIR_APPEARANCE;
-		put_unaligned_le16(hdev->appearance, ptr + 2);
-		scan_rsp_len += 4;
-		ptr += 4;
+		scan_rsp_len = append_appearance(hdev, ptr, scan_rsp_len);
 	}
 
-	memcpy(ptr, adv_instance->scan_rsp_data,
+	memcpy(&ptr[scan_rsp_len], adv_instance->scan_rsp_data,
 	       adv_instance->scan_rsp_len);
 
 	scan_rsp_len += adv_instance->scan_rsp_len;
-	ptr += adv_instance->scan_rsp_len;
 
 	if (instance_flags & MGMT_ADV_FLAG_LOCAL_NAME)
 		scan_rsp_len = append_local_name(hdev, ptr, scan_rsp_len);
diff --git a/net/bluetooth/hci_request.h b/net/bluetooth/hci_request.h
index ac1e110..6b06629 100644
--- a/net/bluetooth/hci_request.h
+++ b/net/bluetooth/hci_request.h
@@ -20,6 +20,8 @@
    SOFTWARE IS DISCLAIMED.
 */
 
+#include <asm/unaligned.h>
+
 #define hci_req_sync_lock(hdev)   mutex_lock(&hdev->req_lock)
 #define hci_req_sync_unlock(hdev) mutex_unlock(&hdev->req_lock)
 
@@ -103,3 +105,24 @@ static inline void hci_update_background_scan(struct hci_dev *hdev)
 
 void hci_request_setup(struct hci_dev *hdev);
 void hci_request_cancel_all(struct hci_dev *hdev);
+
+static inline u16 eir_append_data(u8 *eir, u16 eir_len, u8 type,
+				  u8 *data, u8 data_len)
+{
+	eir[eir_len++] = sizeof(type) + data_len;
+	eir[eir_len++] = type;
+	memcpy(&eir[eir_len], data, data_len);
+	eir_len += data_len;
+
+	return eir_len;
+}
+
+static inline u16 eir_append_le16(u8 *eir, u16 eir_len, u8 type, u16 data)
+{
+	eir[eir_len++] = sizeof(type) + sizeof(data);
+	eir[eir_len++] = type;
+	put_unaligned_le16(data, &eir[eir_len]);
+	eir_len += sizeof(data);
+
+	return eir_len;
+}
diff --git a/net/bluetooth/mgmt.c b/net/bluetooth/mgmt.c
index 19b8a5e..7360380 100644
--- a/net/bluetooth/mgmt.c
+++ b/net/bluetooth/mgmt.c
@@ -867,27 +867,6 @@ static int read_controller_info(struct sock *sk, struct hci_dev *hdev,
 				 sizeof(rp));
 }
 
-static inline u16 eir_append_data(u8 *eir, u16 eir_len, u8 type, u8 *data,
-				  u8 data_len)
-{
-	eir[eir_len++] = sizeof(type) + data_len;
-	eir[eir_len++] = type;
-	memcpy(&eir[eir_len], data, data_len);
-	eir_len += data_len;
-
-	return eir_len;
-}
-
-static inline u16 eir_append_le16(u8 *eir, u16 eir_len, u8 type, u16 data)
-{
-	eir[eir_len++] = sizeof(type) + sizeof(data);
-	eir[eir_len++] = type;
-	put_unaligned_le16(data, &eir[eir_len]);
-	eir_len += sizeof(data);
-
-	return eir_len;
-}
-
 static u16 append_eir_data_to_buf(struct hci_dev *hdev, u8 *eir)
 {
 	u16 eir_len = 0;
-- 
2.7.4

Re: [PATCH 1/3] Bluetooth: Fix local name in scan rsp

[Marcel Holtmann]

Hi Michal,

> Use complete name if it fits. If not and there is short name
> check if it fits. If not then use shortened name as prefix
> of complete name.
> 
> Signed-off-by: Michał Narajowski <michal.narajowski@codecoup.pl>
> ---
> net/bluetooth/hci_request.c | 47 +++++++++++++++++++++++++++++++++------------
> 1 file changed, 35 insertions(+), 12 deletions(-)

all 3 patches have been applied to bluetooth-next tree.

Regards

Marcel