Return-path: Received: from wolverine01.qualcomm.com ([199.106.114.254]:42803 "EHLO wolverine01.qualcomm.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1750993AbcBZOG2 (ORCPT ); Fri, 26 Feb 2016 09:06:28 -0500 From: Jouni Malinen To: Johannes Berg CC: Subject: [PATCH 1/3] cfg80211: Allow a scan request for a specific BSSID Date: Fri, 26 Feb 2016 16:06:04 +0200 Message-ID: <1456495566-14272-1-git-send-email-jouni@qca.qualcomm.com> (sfid-20160226_150634_733221_D3570244) MIME-Version: 1.0 Content-Type: text/plain Sender: linux-wireless-owner@vger.kernel.org List-ID: This allows scans for a specific BSSID to be optimized by the user space application by requesting the driver to set the Probe Request frame BSSID field (Address 3) to the specified BSSID instead of the wildcard BSSID. This prevents other APs from replying which reduces airtime need and latency in getting the response from the target AP through. This is an optimization and as such, it is acceptable for some of the drivers not to support the mechanism. If not supported, the wildcard BSSID will be used and more responses may be received. Signed-off-by: Jouni Malinen --- include/net/cfg80211.h | 2 ++ include/uapi/linux/nl80211.h | 4 +++- net/wireless/nl80211.c | 6 ++++++ 3 files changed, 11 insertions(+), 1 deletion(-) diff --git a/include/net/cfg80211.h b/include/net/cfg80211.h index 9e1b24c..14c0c43 100644 --- a/include/net/cfg80211.h +++ b/include/net/cfg80211.h @@ -1455,6 +1455,7 @@ struct cfg80211_ssid { * @mac_addr_mask: MAC address mask used with randomisation, bits that * are 0 in the mask should be randomised, bits that are 1 should * be taken from the @mac_addr + * @bssid: BSSID to scan for (most commonly, the wildcard BSSID) */ struct cfg80211_scan_request { struct cfg80211_ssid *ssids; @@ -1471,6 +1472,7 @@ struct cfg80211_scan_request { u8 mac_addr[ETH_ALEN] __aligned(2); u8 mac_addr_mask[ETH_ALEN] __aligned(2); + u8 bssid[ETH_ALEN] __aligned(2); /* internal */ struct wiphy *wiphy; diff --git a/include/uapi/linux/nl80211.h b/include/uapi/linux/nl80211.h index 5a30a75..23bf066 100644 --- a/include/uapi/linux/nl80211.h +++ b/include/uapi/linux/nl80211.h @@ -322,7 +322,9 @@ * @NL80211_CMD_GET_SCAN: get scan results * @NL80211_CMD_TRIGGER_SCAN: trigger a new scan with the given parameters * %NL80211_ATTR_TX_NO_CCK_RATE is used to decide whether to send the - * probe requests at CCK rate or not. + * probe requests at CCK rate or not. %NL80211_ATTR_MAC can be used to + * specify a BSSID to scan for; if not included, the wildcard BSSID will + * be used. * @NL80211_CMD_NEW_SCAN_RESULTS: scan notification (as a reply to * NL80211_CMD_GET_SCAN and on the "scan" multicast group) * @NL80211_CMD_SCAN_ABORTED: scan was aborted, for unspecified reasons, diff --git a/net/wireless/nl80211.c b/net/wireless/nl80211.c index 98c9242..1b43f78 100644 --- a/net/wireless/nl80211.c +++ b/net/wireless/nl80211.c @@ -5996,6 +5996,12 @@ static int nl80211_trigger_scan(struct sk_buff *skb, struct genl_info *info) request->no_cck = nla_get_flag(info->attrs[NL80211_ATTR_TX_NO_CCK_RATE]); + if (info->attrs[NL80211_ATTR_MAC]) + memcpy(request->bssid, nla_data(info->attrs[NL80211_ATTR_MAC]), + ETH_ALEN); + else + eth_broadcast_addr(request->bssid); + request->wdev = wdev; request->wiphy = &rdev->wiphy; request->scan_start = jiffies; -- 1.9.1