DMARC-Filter: OpenDMARC Filter v1.3.2 mail.kernel.org DDC7820665
From:   Bob Copeland <me@bobcopeland.com>
To:     Johannes Berg <johannes@sipsolutions.net>
Cc:     linux-wireless@vger.kernel.org, kernel-team@fb.com,
        Bob Copeland <me@bobcopeland.com>,
        Bob Copeland <bobcopeland@fb.com>
Subject: [PATCH] {nl,mac}80211: add rssi to mesh candidates
Date:   Fri, 26 Oct 2018 10:03:50 -0400
Message-Id: <20181026140350.30855-1-me@bobcopeland.com>
Sender: linux-wireless-owner@vger.kernel.org
Precedence: bulk

When peering is in userspace, some implementations may want to control
which peers are accepted based on RSSI in addition to the information
elements being sent today.  Add signal level so that info is available
to clients.

Signed-off-by: Bob Copeland <bobcopeland@fb.com>
---
 include/net/cfg80211.h    |  3 ++-
 net/mac80211/mesh.c       |  3 ++-
 net/mac80211/mesh.h       |  3 ++-
 net/mac80211/mesh_plink.c | 32 ++++++++++++++++++++++----------
 net/wireless/nl80211.c    |  7 +++++--
 5 files changed, 33 insertions(+), 15 deletions(-)

diff --git a/include/net/cfg80211.h b/include/net/cfg80211.h
index 1fa41b7a1be3..2e7710adacb0 100644
--- a/include/net/cfg80211.h
+++ b/include/net/cfg80211.h
@@ -5328,7 +5328,8 @@ void cfg80211_ibss_joined(struct net_device *dev, const u8 *bssid,
  * cfg80211 then sends a notification to userspace.
  */
 void cfg80211_notify_new_peer_candidate(struct net_device *dev,
-		const u8 *macaddr, const u8 *ie, u8 ie_len, gfp_t gfp);
+		const u8 *macaddr, const u8 *ie, u8 ie_len,
+		int sig_dbm, gfp_t gfp);
 
 /**
  * DOC: RFkill integration
diff --git a/net/mac80211/mesh.c b/net/mac80211/mesh.c
index 8bad414c52ad..ea76d4dbdd49 100644
--- a/net/mac80211/mesh.c
+++ b/net/mac80211/mesh.c
@@ -1191,7 +1191,8 @@ static void ieee80211_mesh_rx_bcn_presp(struct ieee80211_sub_if_data *sdata,
 		if (!sdata->u.mesh.user_mpm ||
 		    sdata->u.mesh.mshcfg.rssi_threshold == 0 ||
 		    sdata->u.mesh.mshcfg.rssi_threshold < rx_status->signal)
-			mesh_neighbour_update(sdata, mgmt->sa, &elems);
+			mesh_neighbour_update(sdata, mgmt->sa, &elems,
+					      rx_status);
 	}
 
 	if (ifmsh->sync_ops)
diff --git a/net/mac80211/mesh.h b/net/mac80211/mesh.h
index 21526630bf65..cad6592c52a1 100644
--- a/net/mac80211/mesh.h
+++ b/net/mac80211/mesh.h
@@ -273,7 +273,8 @@ int mesh_gate_num(struct ieee80211_sub_if_data *sdata);
 
 /* Mesh plinks */
 void mesh_neighbour_update(struct ieee80211_sub_if_data *sdata,
-			   u8 *hw_addr, struct ieee802_11_elems *ie);
+			   u8 *hw_addr, struct ieee802_11_elems *ie,
+			   struct ieee80211_rx_status *rx_status);
 bool mesh_peer_accepts_plinks(struct ieee802_11_elems *ie);
 u32 mesh_accept_plinks_update(struct ieee80211_sub_if_data *sdata);
 void mesh_plink_timer(struct timer_list *t);
diff --git a/net/mac80211/mesh_plink.c b/net/mac80211/mesh_plink.c
index 5b5b0f95ffd1..9e8d80533562 100644
--- a/net/mac80211/mesh_plink.c
+++ b/net/mac80211/mesh_plink.c
@@ -513,7 +513,8 @@ __mesh_sta_info_alloc(struct ieee80211_sub_if_data *sdata, u8 *hw_addr)
 
 static struct sta_info *
 mesh_sta_info_alloc(struct ieee80211_sub_if_data *sdata, u8 *addr,
-		    struct ieee802_11_elems *elems)
+		    struct ieee802_11_elems *elems,
+		    struct ieee80211_rx_status *rx_status)
 {
 	struct sta_info *sta = NULL;
 
@@ -521,11 +522,17 @@ mesh_sta_info_alloc(struct ieee80211_sub_if_data *sdata, u8 *addr,
 	if (sdata->u.mesh.user_mpm ||
 	    sdata->u.mesh.security & IEEE80211_MESH_SEC_AUTHED) {
 		if (mesh_peer_accepts_plinks(elems) &&
-		    mesh_plink_availables(sdata))
+		    mesh_plink_availables(sdata)) {
+			int sig = 0;
+
+			if (ieee80211_hw_check(&sdata->local->hw, SIGNAL_DBM))
+				sig = rx_status->signal;
+
 			cfg80211_notify_new_peer_candidate(sdata->dev, addr,
 							   elems->ie_start,
 							   elems->total_len,
-							   GFP_KERNEL);
+							   sig, GFP_KERNEL);
+		}
 	} else
 		sta = __mesh_sta_info_alloc(sdata, addr);
 
@@ -538,13 +545,15 @@ mesh_sta_info_alloc(struct ieee80211_sub_if_data *sdata, u8 *addr,
  * @sdata: local meshif
  * @addr: peer's address
  * @elems: IEs from beacon or mesh peering frame.
+ * @rx_status: rx status for the frame for signal reporting
  *
  * Return existing or newly allocated sta_info under RCU read lock.
  * (re)initialize with given IEs.
  */
 static struct sta_info *
 mesh_sta_info_get(struct ieee80211_sub_if_data *sdata,
-		  u8 *addr, struct ieee802_11_elems *elems) __acquires(RCU)
+		  u8 *addr, struct ieee802_11_elems *elems,
+		  struct ieee80211_rx_status *rx_status) __acquires(RCU)
 {
 	struct sta_info *sta = NULL;
 
@@ -555,7 +564,7 @@ mesh_sta_info_get(struct ieee80211_sub_if_data *sdata,
 	} else {
 		rcu_read_unlock();
 		/* can't run atomic */
-		sta = mesh_sta_info_alloc(sdata, addr, elems);
+		sta = mesh_sta_info_alloc(sdata, addr, elems, rx_status);
 		if (!sta) {
 			rcu_read_lock();
 			return NULL;
@@ -576,17 +585,19 @@ mesh_sta_info_get(struct ieee80211_sub_if_data *sdata,
  * @sdata: local meshif
  * @addr: peer's address
  * @elems: IEs from beacon or mesh peering frame
+ * @rx_status: rx status for the frame for signal reporting
  *
  * Initiates peering if appropriate.
  */
 void mesh_neighbour_update(struct ieee80211_sub_if_data *sdata,
 			   u8 *hw_addr,
-			   struct ieee802_11_elems *elems)
+			   struct ieee802_11_elems *elems,
+			   struct ieee80211_rx_status *rx_status)
 {
 	struct sta_info *sta;
 	u32 changed = 0;
 
-	sta = mesh_sta_info_get(sdata, hw_addr, elems);
+	sta = mesh_sta_info_get(sdata, hw_addr, elems, rx_status);
 	if (!sta)
 		goto out;
 
@@ -1069,7 +1080,8 @@ mesh_plink_get_event(struct ieee80211_sub_if_data *sdata,
 static void
 mesh_process_plink_frame(struct ieee80211_sub_if_data *sdata,
 			 struct ieee80211_mgmt *mgmt,
-			 struct ieee802_11_elems *elems)
+			 struct ieee802_11_elems *elems,
+			 struct ieee80211_rx_status *rx_status)
 {
 
 	struct sta_info *sta;
@@ -1134,7 +1146,7 @@ mesh_process_plink_frame(struct ieee80211_sub_if_data *sdata,
 	if (event == OPN_ACPT) {
 		rcu_read_unlock();
 		/* allocate sta entry if necessary and update info */
-		sta = mesh_sta_info_get(sdata, mgmt->sa, elems);
+		sta = mesh_sta_info_get(sdata, mgmt->sa, elems, rx_status);
 		if (!sta) {
 			mpl_dbg(sdata, "Mesh plink: failed to init peer!\n");
 			goto unlock_rcu;
@@ -1200,5 +1212,5 @@ void mesh_rx_plink_frame(struct ieee80211_sub_if_data *sdata,
 			return;
 	}
 	ieee802_11_parse_elems(baseaddr, len - baselen, true, &elems);
-	mesh_process_plink_frame(sdata, mgmt, &elems);
+	mesh_process_plink_frame(sdata, mgmt, &elems, rx_status);
 }
diff --git a/net/wireless/nl80211.c b/net/wireless/nl80211.c
index 744b5851bbf9..9b57de4cc030 100644
--- a/net/wireless/nl80211.c
+++ b/net/wireless/nl80211.c
@@ -14572,7 +14572,8 @@ void nl80211_send_ibss_bssid(struct cfg80211_registered_device *rdev,
 }
 
 void cfg80211_notify_new_peer_candidate(struct net_device *dev, const u8 *addr,
-					const u8* ie, u8 ie_len, gfp_t gfp)
+					const u8 *ie, u8 ie_len,
+					int sig_dbm, gfp_t gfp)
 {
 	struct wireless_dev *wdev = dev->ieee80211_ptr;
 	struct cfg80211_registered_device *rdev = wiphy_to_rdev(wdev->wiphy);
@@ -14598,7 +14599,9 @@ void cfg80211_notify_new_peer_candidate(struct net_device *dev, const u8 *addr,
 	    nla_put_u32(msg, NL80211_ATTR_IFINDEX, dev->ifindex) ||
 	    nla_put(msg, NL80211_ATTR_MAC, ETH_ALEN, addr) ||
 	    (ie_len && ie &&
-	     nla_put(msg, NL80211_ATTR_IE, ie_len , ie)))
+	     nla_put(msg, NL80211_ATTR_IE, ie_len, ie)) ||
+	    (sig_dbm &&
+	     nla_put_u32(msg, NL80211_ATTR_RX_SIGNAL_DBM, sig_dbm)))
 		goto nla_put_failure;
 
 	genlmsg_end(msg, hdr);
-- 
2.11.0