Return-Path: From: =?UTF-8?q?Micha=C5=82=20Narajowski?= To: linux-bluetooth@vger.kernel.org Cc: =?UTF-8?q?Micha=C5=82=20Narajowski?= Subject: [PATCH v2] Bluetooth: Fix append max 11 bytes of name to scan rsp data Date: Tue, 18 Oct 2016 16:53:38 +0200 Message-Id: <1476802418-23134-1-git-send-email-michal.narajowski@codecoup.pl> MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Sender: linux-bluetooth-owner@vger.kernel.org List-ID: 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 --- net/bluetooth/hci_request.c | 47 +++++++++++++++++++++------------------------ net/bluetooth/mgmt.c | 4 ++-- 2 files changed, 24 insertions(+), 27 deletions(-) diff --git a/net/bluetooth/hci_request.c b/net/bluetooth/hci_request.c index e228842..cfdd2c8 100644 --- a/net/bluetooth/hci_request.c +++ b/net/bluetooth/hci_request.c @@ -971,39 +971,36 @@ 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 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/mgmt.c b/net/bluetooth/mgmt.c index 7360380..cdcadca 100644 --- a/net/bluetooth/mgmt.c +++ b/net/bluetooth/mgmt.c @@ -6030,9 +6030,9 @@ 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 */ + /* max 11 bytes of name should fit in */ if (adv_flags & MGMT_ADV_FLAG_LOCAL_NAME) - max_len -= 3; + max_len -= (1 + 1 + 11); if (adv_flags & (MGMT_ADV_FLAG_APPEARANCE)) max_len -= 4; -- 2.7.4