Append maximum of 10 + 1 bytes of name to scan response data.
Complete name is appended only if exists and is <= 10 characters.
Else append short name if exists or shorten complete name if not.
This makes sure name is consistent across multiple advertising
instances.
Signed-off-by: Michał Narajowski <michal.narajowski@xxxxxxxxxxx>
---
net/bluetooth/hci_request.c | 49 +++++++++++++++++++++------------------------
net/bluetooth/hci_request.h | 2 ++
net/bluetooth/mgmt.c | 26 +++++++++++++++---------
3 files changed, 42 insertions(+), 35 deletions(-)
diff --git a/net/bluetooth/hci_request.c b/net/bluetooth/hci_request.c
index e228842..1015d9c 100644
--- a/net/bluetooth/hci_request.c
+++ b/net/bluetooth/hci_request.c
@@ -969,41 +969,38 @@ void __hci_req_enable_advertising(struct hci_request *req)
hci_req_add(req, HCI_OP_LE_SET_ADV_ENABLE, sizeof(enable), &enable);
}
-static u8 append_local_name(struct hci_dev *hdev, u8 *ptr, u8 ad_len)
+u8 append_local_name(struct hci_dev *hdev, u8 *ptr, u8 ad_len)
{
- size_t complete_len;
size_t short_len;
- int max_len;
-
- max_len = HCI_MAX_AD_LENGTH - ad_len - 2;
- complete_len = strlen(hdev->dev_name);
- short_len = strlen(hdev->short_name);
-
- /* no space left for name */
- if (max_len < 1)
- return ad_len;
+ size_t complete_len;
- /* no name set */
- if (!complete_len)
+ /* no space left for name (+ NULL + type + len) */
+ if ((HCI_MAX_AD_LENGTH - ad_len) < HCI_MAX_SHORT_NAME_LENGTH + 3)
return 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) {
+ /* use complete name if present and fits */
+ complete_len = strlen(hdev->dev_name);
+ if (complete_len && complete_len <= HCI_MAX_SHORT_NAME_LENGTH)
return eir_append_data(ptr, ad_len, EIR_NAME_COMPLETE,
- hdev->dev_name, complete_len);
- }
+ hdev->dev_name, complete_len + 1);
- /* short name set and fits */
- if (short_len && short_len <= max_len) {
+ /* use short name if present */
+ short_len = strlen(hdev->short_name);
+ if (short_len)
return eir_append_data(ptr, ad_len, EIR_NAME_SHORT,
- hdev->short_name, short_len);
- }
+ hdev->short_name, short_len + 1);
- /* no short name set so shorten complete name */
- if (!short_len) {
- return eir_append_data(ptr, ad_len, EIR_NAME_SHORT,
- hdev->dev_name, max_len);
+ /* use shortened full name if present, we already know that name
+ * is longer then HCI_MAX_SHORT_NAME_LENGTH
+ */
+ if (complete_len) {
+ u8 name[HCI_MAX_SHORT_NAME_LENGTH + 1];
+
+ memcpy(name, hdev->dev_name, HCI_MAX_SHORT_NAME_LENGTH);
+ name[HCI_MAX_SHORT_NAME_LENGTH] = '\0';
+
+ return eir_append_data(ptr, ad_len, EIR_NAME_SHORT, name,
+ sizeof(name));
}
return ad_len;
diff --git a/net/bluetooth/hci_request.h b/net/bluetooth/hci_request.h
index 6b06629..dde77bd 100644
--- a/net/bluetooth/hci_request.h
+++ b/net/bluetooth/hci_request.h
@@ -106,6 +106,8 @@ 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);
+u8 append_local_name(struct hci_dev *hdev, u8 *ptr, u8 ad_len);
+
static inline u16 eir_append_data(u8 *eir, u16 eir_len, u8 type,
u8 *data, u8 data_len)
{
diff --git a/net/bluetooth/mgmt.c b/net/bluetooth/mgmt.c
index 7360380..1fba2a0 100644
--- a/net/bluetooth/mgmt.c
+++ b/net/bluetooth/mgmt.c
@@ -6017,7 +6017,15 @@ static int read_adv_features(struct sock *sk, struct hci_dev *hdev,
return err;
}
-static u8 tlv_data_max_len(u32 adv_flags, bool is_adv_data)
+static u8 calculate_name_len(struct hci_dev *hdev)
+{
+ u8 buf[HCI_MAX_SHORT_NAME_LENGTH + 3];
+
+ return append_local_name(hdev, buf, 0);
+}
+
+static u8 tlv_data_max_len(struct hci_dev *hdev, u32 adv_flags,
+ bool is_adv_data)
{
u8 max_len = HCI_MAX_AD_LENGTH;
@@ -6030,9 +6038,8 @@ static u8 tlv_data_max_len(u32 adv_flags, bool is_adv_data)
if (adv_flags & MGMT_ADV_FLAG_TX_POWER)
max_len -= 3;
} else {
- /* at least 1 byte of name should fit in */
if (adv_flags & MGMT_ADV_FLAG_LOCAL_NAME)
- max_len -= 3;
+ max_len -= calculate_name_len(hdev);
if (adv_flags & (MGMT_ADV_FLAG_APPEARANCE))
max_len -= 4;
@@ -6063,12 +6070,13 @@ static bool appearance_managed(u32 adv_flags)
return adv_flags & MGMT_ADV_FLAG_APPEARANCE;
}
-static bool tlv_data_is_valid(u32 adv_flags, u8 *data, u8 len, bool is_adv_data)
+static bool tlv_data_is_valid(struct hci_dev *hdev, u32 adv_flags, u8 *data,
+ u8 len, bool is_adv_data)
{
int i, cur_len;
u8 max_len;
- max_len = tlv_data_max_len(adv_flags, is_adv_data);
+ max_len = tlv_data_max_len(hdev, adv_flags, is_adv_data);
if (len > max_len)
return false;
@@ -6215,8 +6223,8 @@ static int add_advertising(struct sock *sk, struct hci_dev *hdev,
goto unlock;
}
- if (!tlv_data_is_valid(flags, cp->data, cp->adv_data_len, true) ||
- !tlv_data_is_valid(flags, cp->data + cp->adv_data_len,
+ if (!tlv_data_is_valid(hdev, flags, cp->data, cp->adv_data_len, true) ||
+ !tlv_data_is_valid(hdev, flags, cp->data + cp->adv_data_len,
cp->scan_rsp_len, false)) {
err = mgmt_cmd_status(sk, hdev->id, MGMT_OP_ADD_ADVERTISING,
MGMT_STATUS_INVALID_PARAMS);
@@ -6429,8 +6437,8 @@ static int get_adv_size_info(struct sock *sk, struct hci_dev *hdev,
rp.instance = cp->instance;
rp.flags = cp->flags;
- rp.max_adv_data_len = tlv_data_max_len(flags, true);
- rp.max_scan_rsp_len = tlv_data_max_len(flags, false);
+ rp.max_adv_data_len = tlv_data_max_len(hdev, flags, true);
+ rp.max_scan_rsp_len = tlv_data_max_len(hdev, flags, false);
err = mgmt_cmd_complete(sk, hdev->id, MGMT_OP_GET_ADV_SIZE_INFO,
MGMT_STATUS_SUCCESS, &rp, sizeof(rp));
--
2.7.4
--
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