PERR update to be called from mesh code.

* Added mpp_senderror for Mesh Path Selection protocol;
* Added hwmp_senderror that will send an HWMP PERR according to the
supplied reason code;
* Call mpp_senderror when deleting a route with correct reason code
for whether the route is marked proxy or not;
* Call mpp_senderror when trying to forward an individually addressed
frame and there is no forwarding information;

Approved by: adrian

3 files changed, 76 insertions, 2 deletions

diff --git a/sys/net80211/ieee80211_hwmp.c b/sys/net80211/ieee80211_hwmp.c
index 8fee349..61a92c0 100644
--- a/sys/net80211/ieee80211_hwmp.c
+++ b/sys/net80211/ieee80211_hwmp.c
@@ -105,6 +105,9 @@ static int	hwmp_send_perr(struct ieee80211_node *,
 		    const uint8_t [IEEE80211_ADDR_LEN],
 		    const uint8_t [IEEE80211_ADDR_LEN],
 		    struct ieee80211_meshperr_ie *);
+static void	hwmp_senderror(struct ieee80211vap *,
+		    const uint8_t [IEEE80211_ADDR_LEN],
+		    struct ieee80211_mesh_route *, int);
 static void	hwmp_recv_rann(struct ieee80211vap *, struct ieee80211_node *,
 		   const struct ieee80211_frame *,
 		   const struct ieee80211_meshrann_ie *);
@@ -206,6 +209,7 @@ static struct ieee80211_mesh_proto_path mesh_proto_hwmp = {
 	.mpp_ie		= IEEE80211_MESHCONF_PATH_HWMP,
 	.mpp_discover	= hwmp_discover,
 	.mpp_peerdown	= hwmp_peerdown,
+	.mpp_senderror	= hwmp_senderror,
 	.mpp_vattach	= hwmp_vattach,
 	.mpp_vdetach	= hwmp_vdetach,
 	.mpp_newstate	= hwmp_newstate,
@@ -1569,7 +1573,7 @@ done:
 		free(pperr, M_80211_MESH_PERR);
 }
 #undef	PERR_DFLAGS
-#undef	PEER_DADDR
+#undef	PERR_DADDR
 #undef	PERR_DSEQ
 #undef	PERR_DEXTADDR
 #undef	PERR_DRCODE
@@ -1614,6 +1618,64 @@ hwmp_send_perr(struct ieee80211_node *ni,
 	return hwmp_send_action(ni, sa, da, (uint8_t *)perr, perr->perr_len+2);
 }
 
+/*
+ * Called from the rest of the net80211 code (mesh code for example).
+ * NB: IEEE80211_REASON_MESH_PERR_DEST_UNREACH can be trigger by the fact that
+ * a mesh STA is unable to forward an MSDU/MMPDU to a next-hop mesh STA.
+ */
+#define	PERR_DFLAGS(n)		perr.perr_dests[n].dest_flags
+#define	PERR_DADDR(n)		perr.perr_dests[n].dest_addr
+#define	PERR_DSEQ(n)		perr.perr_dests[n].dest_seq
+#define	PERR_DEXTADDR(n)	perr.perr_dests[n].dest_ext_addr
+#define	PERR_DRCODE(n)		perr.perr_dests[n].dest_rcode
+static void
+hwmp_senderror(struct ieee80211vap *vap,
+    const uint8_t addr[IEEE80211_ADDR_LEN],
+    struct ieee80211_mesh_route *rt, int rcode)
+{
+	struct ieee80211_mesh_state *ms = vap->iv_mesh;
+	struct ieee80211_hwmp_route *hr = NULL;
+	struct ieee80211_meshperr_ie perr;
+
+	if (rt != NULL)
+		hr = IEEE80211_MESH_ROUTE_PRIV(rt,
+		    struct ieee80211_hwmp_route);
+
+	perr.perr_ndests = 1;
+	perr.perr_ttl = ms->ms_ttl;
+	PERR_DFLAGS(0) = 0;
+	PERR_DRCODE(0) = rcode;
+
+	switch (rcode) {
+	case IEEE80211_REASON_MESH_PERR_NO_FI:
+		IEEE80211_ADDR_COPY(PERR_DADDR(0), addr);
+		PERR_DSEQ(0) = 0; /* reserved */
+		break;
+	case IEEE80211_REASON_MESH_PERR_NO_PROXY:
+		KASSERT(rt != NULL, ("no proxy info for sending PERR"));
+		KASSERT(rt->rt_flags & IEEE80211_MESHRT_FLAGS_PROXY,
+		    ("route is not marked proxy"));
+		PERR_DFLAGS(0) |= IEEE80211_MESHPERR_FLAGS_AE;
+		IEEE80211_ADDR_COPY(PERR_DADDR(0), vap->iv_myaddr);
+		PERR_DSEQ(0) = rt->rt_ext_seq;
+		IEEE80211_ADDR_COPY(PERR_DEXTADDR(0), addr);
+		break;
+	case IEEE80211_REASON_MESH_PERR_DEST_UNREACH:
+		KASSERT(rt != NULL, ("no route info for sending PERR"));
+		IEEE80211_ADDR_COPY(PERR_DADDR(0), addr);
+		PERR_DSEQ(0) = hr->hr_seq;
+		break;
+	default:
+		KASSERT(0, ("unknown reason code for HWMP PERR (%u)", rcode));
+	}
+	hwmp_send_perr(vap->iv_bss, vap->iv_myaddr, broadcastaddr, &perr);
+}
+#undef	PERR_DFLAGS
+#undef	PEER_DADDR
+#undef	PERR_DSEQ
+#undef	PERR_DEXTADDR
+#undef	PERR_DRCODE
+
 static void
 hwmp_recv_rann(struct ieee80211vap *vap, struct ieee80211_node *ni,
     const struct ieee80211_frame *wh, const struct ieee80211_meshrann_ie *rann)
diff --git a/sys/net80211/ieee80211_mesh.c b/sys/net80211/ieee80211_mesh.c
index c533491..3cc0d3e 100644
--- a/sys/net80211/ieee80211_mesh.c
+++ b/sys/net80211/ieee80211_mesh.c
@@ -344,6 +344,13 @@ ieee80211_mesh_rt_del(struct ieee80211vap *vap,
 	MESH_RT_LOCK(ms);
 	TAILQ_FOREACH_SAFE(rt, &ms->ms_routes, rt_next, next) {
 		if (IEEE80211_ADDR_EQ(rt->rt_dest, dest)) {
+			if (rt->rt_flags & IEEE80211_MESHRT_FLAGS_PROXY) {
+				ms->ms_ppath->mpp_senderror(vap, dest, rt,
+				    IEEE80211_REASON_MESH_PERR_NO_PROXY);
+			} else {
+				ms->ms_ppath->mpp_senderror(vap, dest, rt,
+				    IEEE80211_REASON_MESH_PERR_DEST_UNREACH);
+			}
 			mesh_rt_del(ms, rt);
 			MESH_RT_UNLOCK(ms);
 			return;
@@ -972,10 +979,12 @@ mesh_forward(struct ieee80211vap *vap, struct mbuf *m,
 			 * [Optional] any of the following three actions:
 			 * o silently discard
 			 * o trigger a path discovery
-			 * o inform TA that meshDA is unreachable.
+			 * o inform TA that meshDA is unknown.
 			 */
 			IEEE80211_NOTE_FRAME(vap, IEEE80211_MSG_MESH, wh,
 			    "%s", "frame not fwd'd, no path");
+			ms->ms_ppath->mpp_senderror(vap, whcopy->i_addr3, NULL,
+			    IEEE80211_REASON_MESH_PERR_NO_FI);
 			vap->iv_stats.is_mesh_fwd_nopath++;
 			m_freem(mcopy);
 			return;
diff --git a/sys/net80211/ieee80211_mesh.h b/sys/net80211/ieee80211_mesh.h
index 7501faf..c69764c 100644
--- a/sys/net80211/ieee80211_mesh.h
+++ b/sys/net80211/ieee80211_mesh.h
@@ -449,6 +449,9 @@ struct ieee80211_mesh_proto_path {
 				const uint8_t [IEEE80211_ADDR_LEN],
 				struct mbuf *);
 	void		(*mpp_peerdown)(struct ieee80211_node *);
+	void		(*mpp_senderror)(struct ieee80211vap *,
+				const uint8_t [IEEE80211_ADDR_LEN],
+				struct ieee80211_mesh_route *, int);
 	void		(*mpp_vattach)(struct ieee80211vap *);
 	void		(*mpp_vdetach)(struct ieee80211vap *);
 	int		(*mpp_newstate)(struct ieee80211vap *,