mac80211: Fix the generation of PREQs in proactive RANN mechanism of HWMP

According to Section Y.7.4 Actions on receipt of proactive RANN, an individually
addressed PREQ should be generated towards the neighbor peer mesh STA indicated
in the RANN Sender Address field in the forwarding information.

Signed-off-by: Chun-Yeow Yeoh <yeohchunyeow@gmail.com>
Signed-off-by: Javier Cardona <javier@cozybit.com>
Signed-off-by: Thomas Pedersen <thomas@cozybit.com>
Signed-off-by: John W. Linville <linville@tuxdriver.com>

1 files changed, 15 insertions, 5 deletions

diff --git a/net/mac80211/mesh_hwmp.c b/net/mac80211/mesh_hwmp.c
index 31bc762f209d..639db14f43d2 100644
--- a/net/mac80211/mesh_hwmp.c
+++ b/net/mac80211/mesh_hwmp.c
@@ -513,8 +513,9 @@ static void hwmp_preq_frame_process(struct ieee80211_sub_if_data *sdata,
                                     u8 *preq_elem, u32 metric)
 {
         struct ieee80211_if_mesh *ifmsh = &sdata->u.mesh;
-        struct mesh_path *mpath;
+        struct mesh_path *mpath = NULL;
         u8 *target_addr, *orig_addr;
+        const u8 *da;
         u8 target_flags, ttl;
         u32 orig_sn, target_sn, lifetime;
         bool reply = false;
@@ -591,9 +592,11 @@ static void hwmp_preq_frame_process(struct ieee80211_sub_if_data *sdata,
                 flags = PREQ_IE_FLAGS(preq_elem);
                 preq_id = PREQ_IE_PREQ_ID(preq_elem);
                 hopcount = PREQ_IE_HOPCOUNT(preq_elem) + 1;
+                da = (mpath && mpath->is_root) ?
+                        mpath->rann_snd_addr : broadcast_addr;
                 mesh_path_sel_frame_tx(MPATH_PREQ, flags, orig_addr,
                                 cpu_to_le32(orig_sn), target_flags, target_addr,
-                                cpu_to_le32(target_sn), broadcast_addr,
+                                cpu_to_le32(target_sn), da,
                                 hopcount, ttl, cpu_to_le32(lifetime),
                                 cpu_to_le32(metric), cpu_to_le32(preq_id),
                                 sdata);
@@ -742,8 +745,8 @@ static void hwmp_rann_frame_process(struct ieee80211_sub_if_data *sdata,
         if (memcmp(orig_addr, sdata->vif.addr, ETH_ALEN) == 0)
                 return;
 
-        mhwmp_dbg("received RANN from %pM (is_gate=%d)", orig_addr,
-                        root_is_gate);
+        mhwmp_dbg("received RANN from %pM via neighbour %pM (is_gate=%d)",
+                        orig_addr, mgmt->sa, root_is_gate);
 
         rcu_read_lock();
         mpath = mesh_path_lookup(orig_addr, sdata);
@@ -774,6 +777,11 @@ static void hwmp_rann_frame_process(struct ieee80211_sub_if_data *sdata,
                                        0, sdata);
                 mpath->sn = orig_sn;
         }
+
+        /* Using individually addressed PREQ for root node */
+        memcpy(mpath->rann_snd_addr, mgmt->sa, ETH_ALEN);
+        mpath->is_root = true;
+
         if (root_is_gate)
                 mesh_path_add_gate(mpath);
 
@@ -909,6 +917,7 @@ void mesh_path_start_discovery(struct ieee80211_sub_if_data *sdata)
         struct mesh_preq_queue *preq_node;
         struct mesh_path *mpath;
         u8 ttl, target_flags;
+        const u8 *da;
         u32 lifetime;
 
         spin_lock_bh(&ifmsh->mesh_preq_queue_lock);
@@ -971,9 +980,10 @@ void mesh_path_start_discovery(struct ieee80211_sub_if_data *sdata)
                 target_flags = MP_F_RF;
 
         spin_unlock_bh(&mpath->state_lock);
+        da = (mpath->is_root) ? mpath->rann_snd_addr : broadcast_addr;
         mesh_path_sel_frame_tx(MPATH_PREQ, 0, sdata->vif.addr,
                         cpu_to_le32(ifmsh->sn), target_flags, mpath->dst,
-                        cpu_to_le32(mpath->sn), broadcast_addr, 0,
+                        cpu_to_le32(mpath->sn), da, 0,
                         ttl, cpu_to_le32(lifetime), 0,
                         cpu_to_le32(ifmsh->preq_id++), sdata);
         mod_timer(&mpath->timer, jiffies + mpath->discovery_timeout);