{nl,cfg,mac}80211: Add support of setting non-forwarding entity in Mesh

A mesh node that joins the mesh network is by default a forwarding entity. This patch allows
the mesh node to set as non-forwarding entity. Whenever dot11MeshForwarding is set to 0, the
mesh node can prevent itself from forwarding the traffic which is not destined to him.
Signed-off-by: Chun-Yeow Yeoh <yeohchunyeow@gmail.com>
Signed-off-by: John W. Linville <linville@tuxdriver.com>

include/linux/nl80211.h

@@ -2104,6 +2104,9 @@ enum nl80211_mntr_flags {
  * TUs) during which a mesh STA can send only one Action frame containing a
  * PERR element.
  *
+ * @NL80211_MESHCONF_FORWARDING: set Mesh STA as forwarding or non-forwarding
+ * or forwarding entity (default is TRUE - forwarding entity)
+ *
  * @NL80211_MESHCONF_ATTR_MAX: highest possible mesh configuration attribute
  *
  * @__NL80211_MESHCONF_ATTR_AFTER_LAST: internal use
@@ -2128,6 +2131,7 @@ enum nl80211_meshconf_params {
 	NL80211_MESHCONF_HWMP_RANN_INTERVAL,
 	NL80211_MESHCONF_GATE_ANNOUNCEMENTS,
 	NL80211_MESHCONF_HWMP_PERR_MIN_INTERVAL,
+	NL80211_MESHCONF_FORWARDING,
 
 	/* keep last */
 	__NL80211_MESHCONF_ATTR_AFTER_LAST,

include/net/cfg80211.h

@@ -798,6 +798,7 @@ struct mesh_config {
 	 * mesh gate, but not necessarily using the gate announcement protocol.
 	 * Still keeping the same nomenclature to be in sync with the spec. */
 	bool  dot11MeshGateAnnouncementProtocol;
+	bool dot11MeshForwarding;
 };
 
 /**

net/mac80211/cfg.c

@@ -1346,6 +1346,8 @@ static int ieee80211_update_mesh_config(struct wiphy *wiphy,
 		conf->dot11MeshHWMPRannInterval =
 			nconf->dot11MeshHWMPRannInterval;
 	}
+	if (_chg_mesh_attr(NL80211_MESHCONF_FORWARDING, mask))
+		conf->dot11MeshForwarding = nconf->dot11MeshForwarding;
 	return 0;
 }
 

net/mac80211/debugfs_netdev.c

@@ -422,6 +422,7 @@ IEEE80211_IF_FILE(dot11MeshGateAnnouncementProtocol,
 		u.mesh.mshcfg.dot11MeshGateAnnouncementProtocol, DEC);
 IEEE80211_IF_FILE(dot11MeshHWMPRannInterval,
 		u.mesh.mshcfg.dot11MeshHWMPRannInterval, DEC);
+IEEE80211_IF_FILE(dot11MeshForwarding, u.mesh.mshcfg.dot11MeshForwarding, DEC);
 #endif
 
 

net/mac80211/mesh_hwmp.c

@@ -575,7 +575,7 @@ static void hwmp_preq_frame_process(struct ieee80211_sub_if_data *sdata,
 			ifmsh->mshstats.dropped_frames_ttl++;
 	}
 
-	if (forward) {
+	if (forward && ifmsh->mshcfg.dot11MeshForwarding) {
 		u32 preq_id;
 		u8 hopcount, flags;
 

net/wireless/mesh.c

@@ -55,6 +55,7 @@ const struct mesh_config default_mesh_config = {
 	.min_discovery_timeout = MESH_MIN_DISCOVERY_TIMEOUT,
 	.dot11MeshHWMPRannInterval = MESH_RANN_INTERVAL,
 	.dot11MeshGateAnnouncementProtocol = false,
+	.dot11MeshForwarding = true,
 };
 
 const struct mesh_setup default_mesh_setup = {

net/wireless/nl80211.c

@@ -3258,6 +3258,8 @@ static int nl80211_get_mesh_config(struct sk_buff *skb,
 			cur_params.dot11MeshHWMPRannInterval);
 	NLA_PUT_U8(msg, NL80211_MESHCONF_GATE_ANNOUNCEMENTS,
 			cur_params.dot11MeshGateAnnouncementProtocol);
+	NLA_PUT_U8(msg, NL80211_MESHCONF_FORWARDING,
+			cur_params.dot11MeshForwarding);
 	nla_nest_end(msg, pinfoattr);
 	genlmsg_end(msg, hdr);
 	return genlmsg_reply(msg, info);
@@ -3289,6 +3291,7 @@ static const struct nla_policy nl80211_meshconf_params_policy[NL80211_MESHCONF_A
 	[NL80211_MESHCONF_HWMP_ROOTMODE] = { .type = NLA_U8 },
 	[NL80211_MESHCONF_HWMP_RANN_INTERVAL] = { .type = NLA_U16 },
 	[NL80211_MESHCONF_GATE_ANNOUNCEMENTS] = { .type = NLA_U8 },
+	[NL80211_MESHCONF_FORWARDING] = { .type = NLA_U8 },
 };
 
 static const struct nla_policy
@@ -3378,6 +3381,8 @@ do {\
 			dot11MeshGateAnnouncementProtocol, mask,
 			NL80211_MESHCONF_GATE_ANNOUNCEMENTS,
 			nla_get_u8);
+	FILL_IN_MESH_PARAM_IF_SET(tb, cfg, dot11MeshForwarding,
+			mask, NL80211_MESHCONF_FORWARDING, nla_get_u8);
 	if (mask_out)
 		*mask_out = mask;