batman-adv: Add IPv4 link-local/IPv6-ll-all-nodes multicast support

With this patch a node may additionally perform the dropping or unicasting behaviour for a link-local IPv4 and link-local-all-nodes IPv6 multicast packet, too. The extra counter and BATADV_MCAST_WANT_ALL_UNSNOOPABLES flag is needed because with a future bridge snooping support integration a node with a bridge on top of its soft interface is not able to reliably detect its multicast listeners for IPv4 link-local and the IPv6 link-local-all-nodes addresses anymore (see RFC4541, section 2.1.2.2 and section 3). Even though this new flag does make "no difference" now, it'll ensure a seamless integration of multicast bridge support without needing to break compatibility later. Also note, that even with multicast bridge support it won't be possible to optimize 224.0.0.x and ff02::1 towards nodes with bridges, they will always receive these ranges. Signed-off-by: Linus Lüssing <linus.luessing@web.de> Signed-off-by: Marek Lindner <mareklindner@neomailbox.ch> Signed-off-by: Antonio Quartulli <antonio@meshcoding.com>

batman-adv: Add IPv4 link-local/IPv6-ll-all-nodes multicast support
With this patch a node may additionally perform the dropping or unicasting behaviour for a link-local IPv4 and link-local-all-nodes IPv6 multicast packet, too. The extra counter and BATADV_MCAST_WANT_ALL_UNSNOOPABLES flag is needed because with a future bridge snooping support integration a node with a bridge on top of its soft interface is not able to reliably detect its multicast listeners for IPv4 link-local and the IPv6 link-local-all-nodes addresses anymore (see RFC4541, section 2.1.2.2 and section 3). Even though this new flag does make "no difference" now, it'll ensure a seamless integration of multicast bridge support without needing to break compatibility later. Also note, that even with multicast bridge support it won't be possible to optimize 224.0.0.x and ff02::1 towards nodes with bridges, they will always receive these ranges. Signed-off-by: Linus Lüssing <linus.luessing@web.de> Signed-off-by: Marek Lindner <mareklindner@neomailbox.ch> Signed-off-by: Antonio Quartulli <antonio@meshcoding.com>
Linus Lüssing · Antonio Quartulli
1 parent 1d8ab8d3c1
Showing 6 changed files with 156 additions and 8 deletions Side-by-side Diff
net/batman-adv/main.c
net/batman-adv/main.h
net/batman-adv/multicast.c
net/batman-adv/packet.h
net/batman-adv/soft-interface.c
net/batman-adv/types.h
@@ -111,6 +111,9 @@
 	spin_lock_init(&bat_priv->tt.last_changeset_lock);
 	spin_lock_init(&bat_priv->tt.commit_lock);
 	spin_lock_init(&bat_priv->gw.list_lock);
+#ifdef CONFIG_BATMAN_ADV_MCAST
+	spin_lock_init(&bat_priv->mcast.want_lists_lock);
+#endif
 	spin_lock_init(&bat_priv->tvlv.container_list_lock);
 	spin_lock_init(&bat_priv->tvlv.handler_list_lock);
 	spin_lock_init(&bat_priv->softif_vlan_list_lock);
@@ -118,6 +121,9 @@
 	INIT_HLIST_HEAD(&bat_priv->forw_bat_list);
 	INIT_HLIST_HEAD(&bat_priv->forw_bcast_list);
 	INIT_HLIST_HEAD(&bat_priv->gw.list);
+#ifdef CONFIG_BATMAN_ADV_MCAST
+	INIT_HLIST_HEAD(&bat_priv->mcast.want_all_unsnoopables_list);
+#endif
 	INIT_LIST_HEAD(&bat_priv->tt.changes_list);
 	INIT_LIST_HEAD(&bat_priv->tt.req_list);
 	INIT_LIST_HEAD(&bat_priv->tt.roam_list);
@@ -177,6 +177,7 @@
 #include <linux/slab.h>
 #include <net/sock.h>		/* struct sock */
 #include <net/addrconf.h>	/* ipv6 address stuff */
+#include <linux/ip.h>
 #include <net/rtnetlink.h>
 #include <linux/jiffies.h>
 #include <linux/seq_file.h>
@@ -248,9 +248,48 @@
 }
  
 /**
+ * batadv_mcast_forw_mode_check_ipv4 - check for optimized forwarding potential
+ * @bat_priv: the bat priv with all the soft interface information
+ * @skb: the IPv4 packet to check
+ * @is_unsnoopable: stores whether the destination is snoopable
+ *
+ * Checks whether the given IPv4 packet has the potential to be forwarded with a
+ * mode more optimal than classic flooding.
+ *
+ * If so then returns 0. Otherwise -EINVAL is returned or -ENOMEM in case of
+ * memory allocation failure.
+ */
+static int batadv_mcast_forw_mode_check_ipv4(struct batadv_priv *bat_priv,
+					     struct sk_buff *skb,
+					     bool *is_unsnoopable)
+{
+	struct iphdr *iphdr;
+
+	/* We might fail due to out-of-memory -> drop it */
+	if (!pskb_may_pull(skb, sizeof(struct ethhdr) + sizeof(*iphdr)))
+		return -ENOMEM;
+
+	iphdr = ip_hdr(skb);
+
+	/* TODO: Implement Multicast Router Discovery (RFC4286),
+	 * then allow scope > link local, too
+	 */
+	if (!ipv4_is_local_multicast(iphdr->daddr))
+		return -EINVAL;
+
+	/* link-local multicast listeners behind a bridge are
+	 * not snoopable (see RFC4541, section 2.1.2.2)
+	 */
+	*is_unsnoopable = true;
+
+	return 0;
+}
+
+/**
  * batadv_mcast_forw_mode_check_ipv6 - check for optimized forwarding potential
  * @bat_priv: the bat priv with all the soft interface information
  * @skb: the IPv6 packet to check
+ * @is_unsnoopable: stores whether the destination is snoopable
  *
  * Checks whether the given IPv6 packet has the potential to be forwarded with a
  * mode more optimal than classic flooding.
@@ -259,7 +298,8 @@
  * of memory.
  */
 static int batadv_mcast_forw_mode_check_ipv6(struct batadv_priv *bat_priv,
-					     struct sk_buff *skb)
+					     struct sk_buff *skb,
+					     bool *is_unsnoopable)
 {
 	struct ipv6hdr *ip6hdr;
  
@@ -279,7 +319,7 @@
 	 * not snoopable (see RFC4541, section 3, paragraph 3)
 	 */
 	if (ipv6_addr_is_ll_all_nodes(&ip6hdr->daddr))
-		return -EINVAL;
+		*is_unsnoopable = true;
  
 	return 0;
 }
@@ -288,6 +328,7 @@
  * batadv_mcast_forw_mode_check - check for optimized forwarding potential
  * @bat_priv: the bat priv with all the soft interface information
  * @skb: the multicast frame to check
+ * @is_unsnoopable: stores whether the destination is snoopable
  *
  * Checks whether the given multicast ethernet frame has the potential to be
  * forwarded with a mode more optimal than classic flooding.
@@ -296,7 +337,8 @@
  * of memory.
  */
 static int batadv_mcast_forw_mode_check(struct batadv_priv *bat_priv,
-					struct sk_buff *skb)
+					struct sk_buff *skb,
+					bool *is_unsnoopable)
 {
 	struct ethhdr *ethhdr = eth_hdr(skb);
  
  
@@ -307,8 +349,12 @@
 		return -EINVAL;
  
 	switch (ntohs(ethhdr->h_proto)) {
+	case ETH_P_IP:
+		return batadv_mcast_forw_mode_check_ipv4(bat_priv, skb,
+							 is_unsnoopable);
 	case ETH_P_IPV6:
-		return batadv_mcast_forw_mode_check_ipv6(bat_priv, skb);
+		return batadv_mcast_forw_mode_check_ipv6(bat_priv, skb,
+							 is_unsnoopable);
 	default:
 		return -EINVAL;
 	}
@@ -331,6 +377,33 @@
 }
  
 /**
+ * batadv_mcast_want_forw_unsnoop_node_get - get a node with an unsnoopable flag
+ * @bat_priv: the bat priv with all the soft interface information
+ *
+ * Returns an orig_node which has the BATADV_MCAST_WANT_ALL_UNSNOOPABLES flag
+ * set and increases its refcount.
+ */
+static struct batadv_orig_node *
+batadv_mcast_forw_unsnoop_node_get(struct batadv_priv *bat_priv)
+{
+	struct batadv_orig_node *tmp_orig_node, *orig_node = NULL;
+
+	rcu_read_lock();
+	hlist_for_each_entry_rcu(tmp_orig_node,
+				 &bat_priv->mcast.want_all_unsnoopables_list,
+				 mcast_want_all_unsnoopables_node) {
+		if (!atomic_inc_not_zero(&orig_node->refcount))
+			continue;
+
+		orig_node = tmp_orig_node;
+		break;
+	}
+	rcu_read_unlock();
+
+	return orig_node;
+}
+
+/**
  * batadv_mcast_forw_mode - check on how to forward a multicast packet
  * @bat_priv: the bat priv with all the soft interface information
  * @skb: The multicast packet to check
  
  
@@ -344,10 +417,11 @@
 batadv_mcast_forw_mode(struct batadv_priv *bat_priv, struct sk_buff *skb,
 		       struct batadv_orig_node **orig)
 {
+	int ret, tt_count, unsnoop_count, total_count;
+	bool is_unsnoopable = false;
 	struct ethhdr *ethhdr;
-	int ret, tt_count;
  
-	ret = batadv_mcast_forw_mode_check(bat_priv, skb);
+	ret = batadv_mcast_forw_mode_check(bat_priv, skb, &is_unsnoopable);
 	if (ret == -ENOMEM)
 		return BATADV_FORW_NONE;
 	else if (ret < 0)
  
  
@@ -357,10 +431,18 @@
  
 	tt_count = batadv_tt_global_hash_count(bat_priv, ethhdr->h_dest,
 					       BATADV_NO_FLAGS);
+	unsnoop_count = !is_unsnoopable ? 0 :
+			atomic_read(&bat_priv->mcast.num_want_all_unsnoopables);
  
-	switch (tt_count) {
+	total_count = tt_count + unsnoop_count;
+
+	switch (total_count) {
 	case 1:
-		*orig = batadv_mcast_forw_tt_node_get(bat_priv, ethhdr);
+		if (tt_count)
+			*orig = batadv_mcast_forw_tt_node_get(bat_priv, ethhdr);
+		else if (unsnoop_count)
+			*orig = batadv_mcast_forw_unsnoop_node_get(bat_priv);
+
 		if (*orig)
 			return BATADV_FORW_SINGLE;
  
@@ -373,6 +455,39 @@
 }
  
 /**
+ * batadv_mcast_want_unsnoop_update - update unsnoop counter and list
+ * @bat_priv: the bat priv with all the soft interface information
+ * @orig: the orig_node which multicast state might have changed of
+ * @mcast_flags: flags indicating the new multicast state
+ *
+ * If the BATADV_MCAST_WANT_ALL_UNSNOOPABLES flag of this originator,
+ * orig, has toggled then this method updates counter and list accordingly.
+ */
+static void batadv_mcast_want_unsnoop_update(struct batadv_priv *bat_priv,
+					     struct batadv_orig_node *orig,
+					     uint8_t mcast_flags)
+{
+	/* switched from flag unset to set */
+	if (mcast_flags & BATADV_MCAST_WANT_ALL_UNSNOOPABLES &&
+	    !(orig->mcast_flags & BATADV_MCAST_WANT_ALL_UNSNOOPABLES)) {
+		atomic_inc(&bat_priv->mcast.num_want_all_unsnoopables);
+
+		spin_lock_bh(&bat_priv->mcast.want_lists_lock);
+		hlist_add_head_rcu(&orig->mcast_want_all_unsnoopables_node,
+				   &bat_priv->mcast.want_all_unsnoopables_list);
+		spin_unlock_bh(&bat_priv->mcast.want_lists_lock);
+	/* switched from flag set to unset */
+	} else if (!(mcast_flags & BATADV_MCAST_WANT_ALL_UNSNOOPABLES) &&
+		   orig->mcast_flags & BATADV_MCAST_WANT_ALL_UNSNOOPABLES) {
+		atomic_dec(&bat_priv->mcast.num_want_all_unsnoopables);
+
+		spin_lock_bh(&bat_priv->mcast.want_lists_lock);
+		hlist_del_rcu(&orig->mcast_want_all_unsnoopables_node);
+		spin_unlock_bh(&bat_priv->mcast.want_lists_lock);
+	}
+}
+
+/**
  * batadv_mcast_tvlv_ogm_handler_v1 - process incoming multicast tvlv container
  * @bat_priv: the bat priv with all the soft interface information
  * @orig: the orig_node of the ogm
@@ -416,6 +531,8 @@
 	    (tvlv_value_len >= sizeof(mcast_flags)))
 		mcast_flags = *(uint8_t *)tvlv_value;
  
+	batadv_mcast_want_unsnoop_update(bat_priv, orig, mcast_flags);
+
 	orig->mcast_flags = mcast_flags;
 }
  
@@ -452,5 +569,7 @@
  
 	if (!(orig->capabilities & BATADV_ORIG_CAPA_HAS_MCAST))
 		atomic_dec(&bat_priv->mcast.num_disabled);
+
+	batadv_mcast_want_unsnoop_update(bat_priv, orig, BATADV_NO_FLAGS);
 }
@@ -89,6 +89,15 @@
 	BATADV_PARAMETER_PROBLEM       = 12,
 };
  
+/**
+ * enum batadv_mcast_flags - flags for multicast capabilities and settings
+ * @BATADV_MCAST_WANT_ALL_UNSNOOPABLES: we want all packets destined for
+ *  224.0.0.0/24 or ff02::1
+ */
+enum batadv_mcast_flags {
+	BATADV_MCAST_WANT_ALL_UNSNOOPABLES	= BIT(0),
+};
+
 /* tt data subtypes */
 #define BATADV_TT_DATA_TYPE_MASK 0x0F
  
@@ -710,6 +710,7 @@
 	bat_priv->mcast.flags = BATADV_NO_FLAGS;
 	atomic_set(&bat_priv->multicast_mode, 1);
 	atomic_set(&bat_priv->mcast.num_disabled, 0);
+	atomic_set(&bat_priv->mcast.num_want_all_unsnoopables, 0);
 #endif
 	atomic_set(&bat_priv->gw_mode, BATADV_GW_MODE_OFF);
 	atomic_set(&bat_priv->gw_sel_class, 20);
@@ -205,6 +205,8 @@
  * @last_seen: time when last packet from this node was received
  * @bcast_seqno_reset: time when the broadcast seqno window was reset
  * @mcast_flags: multicast flags announced by the orig node
+ * @mcast_want_all_unsnoop_node: a list node for the
+ *  mcast.want_all_unsnoopables list
  * @capabilities: announced capabilities of this originator
  * @capa_initialized: bitfield to remember whether a capability was initialized
  * @last_ttvn: last seen translation table version number
@@ -249,6 +251,7 @@
 	unsigned long bcast_seqno_reset;
 #ifdef CONFIG_BATMAN_ADV_MCAST
 	uint8_t mcast_flags;
+	struct hlist_node mcast_want_all_unsnoopables_node;
 #endif
 	uint8_t capabilities;
 	uint8_t capa_initialized;
  
  
  
@@ -619,15 +622,24 @@
 /**
  * struct batadv_priv_mcast - per mesh interface mcast data
  * @mla_list: list of multicast addresses we are currently announcing via TT
+ * @want_all_unsnoopables_list: a list of orig_nodes wanting all unsnoopable
+ *  multicast traffic
  * @flags: the flags we have last sent in our mcast tvlv
  * @enabled: whether the multicast tvlv is currently enabled
  * @num_disabled: number of nodes that have no mcast tvlv
+ * @num_want_all_unsnoopables: number of nodes wanting unsnoopable IP traffic
+ * @want_lists_lock: lock for protecting modifications to mcast want lists
+ *  (traversals are rcu-locked)
  */
 struct batadv_priv_mcast {
 	struct hlist_head mla_list;
+	struct hlist_head want_all_unsnoopables_list;
 	uint8_t flags;
 	bool enabled;
 	atomic_t num_disabled;
+	atomic_t num_want_all_unsnoopables;
+	/* protects want_all_unsnoopables_list */
+	spinlock_t want_lists_lock;
 };
 #endif
...	...	@@ -111,6 +111,9 @@
111	111	spin_lock_init(&bat_priv->tt.last_changeset_lock);
112	112	spin_lock_init(&bat_priv->tt.commit_lock);
113	113	spin_lock_init(&bat_priv->gw.list_lock);
	114	+#ifdef CONFIG_BATMAN_ADV_MCAST
	115	+ spin_lock_init(&bat_priv->mcast.want_lists_lock);
	116	+#endif
114	117	spin_lock_init(&bat_priv->tvlv.container_list_lock);
115	118	spin_lock_init(&bat_priv->tvlv.handler_list_lock);
116	119	spin_lock_init(&bat_priv->softif_vlan_list_lock);
...	...	@@ -118,6 +121,9 @@
118	121	INIT_HLIST_HEAD(&bat_priv->forw_bat_list);
119	122	INIT_HLIST_HEAD(&bat_priv->forw_bcast_list);
120	123	INIT_HLIST_HEAD(&bat_priv->gw.list);
	124	+#ifdef CONFIG_BATMAN_ADV_MCAST
	125	+ INIT_HLIST_HEAD(&bat_priv->mcast.want_all_unsnoopables_list);
	126	+#endif
121	127	INIT_LIST_HEAD(&bat_priv->tt.changes_list);
122	128	INIT_LIST_HEAD(&bat_priv->tt.req_list);
123	129	INIT_LIST_HEAD(&bat_priv->tt.roam_list);
...	...	@@ -177,6 +177,7 @@
177	177	#include <linux/slab.h>
178	178	#include <net/sock.h> /* struct sock */
179	179	#include <net/addrconf.h> /* ipv6 address stuff */
	180	+#include <linux/ip.h>
180	181	#include <net/rtnetlink.h>
181	182	#include <linux/jiffies.h>
182	183	#include <linux/seq_file.h>
...	...	@@ -248,9 +248,48 @@
248	248	}
249	249
250	250	/**
	251	+ * batadv_mcast_forw_mode_check_ipv4 - check for optimized forwarding potential
	252	+ * @bat_priv: the bat priv with all the soft interface information
	253	+ * @skb: the IPv4 packet to check
	254	+ * @is_unsnoopable: stores whether the destination is snoopable
	255	+ *
	256	+ * Checks whether the given IPv4 packet has the potential to be forwarded with a
	257	+ * mode more optimal than classic flooding.
	258	+ *
	259	+ * If so then returns 0. Otherwise -EINVAL is returned or -ENOMEM in case of
	260	+ * memory allocation failure.
	261	+ */
	262	+static int batadv_mcast_forw_mode_check_ipv4(struct batadv_priv *bat_priv,
	263	+ struct sk_buff *skb,
	264	+ bool *is_unsnoopable)
	265	+{
	266	+ struct iphdr *iphdr;
	267	+
	268	+ /* We might fail due to out-of-memory -> drop it */
	269	+ if (!pskb_may_pull(skb, sizeof(struct ethhdr) + sizeof(*iphdr)))
	270	+ return -ENOMEM;
	271	+
	272	+ iphdr = ip_hdr(skb);
	273	+
	274	+ /* TODO: Implement Multicast Router Discovery (RFC4286),
	275	+ * then allow scope > link local, too
	276	+ */
	277	+ if (!ipv4_is_local_multicast(iphdr->daddr))
	278	+ return -EINVAL;
	279	+
	280	+ /* link-local multicast listeners behind a bridge are
	281	+ * not snoopable (see RFC4541, section 2.1.2.2)
	282	+ */
	283	+ *is_unsnoopable = true;
	284	+
	285	+ return 0;
	286	+}
	287	+
	288	+/**
251	289	* batadv_mcast_forw_mode_check_ipv6 - check for optimized forwarding potential
252	290	* @bat_priv: the bat priv with all the soft interface information
253	291	* @skb: the IPv6 packet to check
	292	+ * @is_unsnoopable: stores whether the destination is snoopable
254	293	*
255	294	* Checks whether the given IPv6 packet has the potential to be forwarded with a
256	295	* mode more optimal than classic flooding.
...	...	@@ -259,7 +298,8 @@
259	298	* of memory.
260	299	*/
261	300	static int batadv_mcast_forw_mode_check_ipv6(struct batadv_priv *bat_priv,
262		- struct sk_buff *skb)
	301	+ struct sk_buff *skb,
	302	+ bool *is_unsnoopable)
263	303	{
264	304	struct ipv6hdr *ip6hdr;
265	305
...	...	@@ -279,7 +319,7 @@
279	319	* not snoopable (see RFC4541, section 3, paragraph 3)
280	320	*/
281	321	if (ipv6_addr_is_ll_all_nodes(&ip6hdr->daddr))
282		- return -EINVAL;
	322	+ *is_unsnoopable = true;
283	323
284	324	return 0;
285	325	}
...	...	@@ -288,6 +328,7 @@
288	328	* batadv_mcast_forw_mode_check - check for optimized forwarding potential
289	329	* @bat_priv: the bat priv with all the soft interface information
290	330	* @skb: the multicast frame to check
	331	+ * @is_unsnoopable: stores whether the destination is snoopable
291	332	*
292	333	* Checks whether the given multicast ethernet frame has the potential to be
293	334	* forwarded with a mode more optimal than classic flooding.
...	...	@@ -296,7 +337,8 @@
296	337	* of memory.
297	338	*/
298	339	static int batadv_mcast_forw_mode_check(struct batadv_priv *bat_priv,
299		- struct sk_buff *skb)
	340	+ struct sk_buff *skb,
	341	+ bool *is_unsnoopable)
300	342	{
301	343	struct ethhdr *ethhdr = eth_hdr(skb);
302	344
303	345
...	...	@@ -307,8 +349,12 @@
307	349	return -EINVAL;
308	350
309	351	switch (ntohs(ethhdr->h_proto)) {
	352	+ case ETH_P_IP:
	353	+ return batadv_mcast_forw_mode_check_ipv4(bat_priv, skb,
	354	+ is_unsnoopable);
310	355	case ETH_P_IPV6:
311		- return batadv_mcast_forw_mode_check_ipv6(bat_priv, skb);
	356	+ return batadv_mcast_forw_mode_check_ipv6(bat_priv, skb,
	357	+ is_unsnoopable);
312	358	default:
313	359	return -EINVAL;
314	360	}
...	...	@@ -331,6 +377,33 @@
331	377	}
332	378
333	379	/**
	380	+ * batadv_mcast_want_forw_unsnoop_node_get - get a node with an unsnoopable flag
	381	+ * @bat_priv: the bat priv with all the soft interface information
	382	+ *
	383	+ * Returns an orig_node which has the BATADV_MCAST_WANT_ALL_UNSNOOPABLES flag
	384	+ * set and increases its refcount.
	385	+ */
	386	+static struct batadv_orig_node *
	387	+batadv_mcast_forw_unsnoop_node_get(struct batadv_priv *bat_priv)
	388	+{
	389	+ struct batadv_orig_node tmp_orig_node, orig_node = NULL;
	390	+
	391	+ rcu_read_lock();
	392	+ hlist_for_each_entry_rcu(tmp_orig_node,
	393	+ &bat_priv->mcast.want_all_unsnoopables_list,
	394	+ mcast_want_all_unsnoopables_node) {
	395	+ if (!atomic_inc_not_zero(&orig_node->refcount))
	396	+ continue;
	397	+
	398	+ orig_node = tmp_orig_node;
	399	+ break;
	400	+ }
	401	+ rcu_read_unlock();
	402	+
	403	+ return orig_node;
	404	+}
	405	+
	406	+/**
334	407	* batadv_mcast_forw_mode - check on how to forward a multicast packet
335	408	* @bat_priv: the bat priv with all the soft interface information
336	409	* @skb: The multicast packet to check
337	410
338	411
...	...	@@ -344,10 +417,11 @@
344	417	batadv_mcast_forw_mode(struct batadv_priv bat_priv, struct sk_buff skb,
345	418	struct batadv_orig_node **orig)
346	419	{
	420	+ int ret, tt_count, unsnoop_count, total_count;
	421	+ bool is_unsnoopable = false;
347	422	struct ethhdr *ethhdr;
348		- int ret, tt_count;
349	423
350		- ret = batadv_mcast_forw_mode_check(bat_priv, skb);
	424	+ ret = batadv_mcast_forw_mode_check(bat_priv, skb, &is_unsnoopable);
351	425	if (ret == -ENOMEM)
352	426	return BATADV_FORW_NONE;
353	427	else if (ret < 0)
354	428
355	429
...	...	@@ -357,10 +431,18 @@
357	431
358	432	tt_count = batadv_tt_global_hash_count(bat_priv, ethhdr->h_dest,
359	433	BATADV_NO_FLAGS);
	434	+ unsnoop_count = !is_unsnoopable ? 0 :
	435	+ atomic_read(&bat_priv->mcast.num_want_all_unsnoopables);
360	436
361		- switch (tt_count) {
	437	+ total_count = tt_count + unsnoop_count;
	438	+
	439	+ switch (total_count) {
362	440	case 1:
363		- *orig = batadv_mcast_forw_tt_node_get(bat_priv, ethhdr);
	441	+ if (tt_count)
	442	+ *orig = batadv_mcast_forw_tt_node_get(bat_priv, ethhdr);
	443	+ else if (unsnoop_count)
	444	+ *orig = batadv_mcast_forw_unsnoop_node_get(bat_priv);
	445	+
364	446	if (*orig)
365	447	return BATADV_FORW_SINGLE;
366	448
...	...	@@ -373,6 +455,39 @@
373	455	}
374	456
375	457	/**
	458	+ * batadv_mcast_want_unsnoop_update - update unsnoop counter and list
	459	+ * @bat_priv: the bat priv with all the soft interface information
	460	+ * @orig: the orig_node which multicast state might have changed of
	461	+ * @mcast_flags: flags indicating the new multicast state
	462	+ *
	463	+ * If the BATADV_MCAST_WANT_ALL_UNSNOOPABLES flag of this originator,
	464	+ * orig, has toggled then this method updates counter and list accordingly.
	465	+ */
	466	+static void batadv_mcast_want_unsnoop_update(struct batadv_priv *bat_priv,
	467	+ struct batadv_orig_node *orig,
	468	+ uint8_t mcast_flags)
	469	+{
	470	+ /* switched from flag unset to set */
	471	+ if (mcast_flags & BATADV_MCAST_WANT_ALL_UNSNOOPABLES &&
	472	+ !(orig->mcast_flags & BATADV_MCAST_WANT_ALL_UNSNOOPABLES)) {
	473	+ atomic_inc(&bat_priv->mcast.num_want_all_unsnoopables);
	474	+
	475	+ spin_lock_bh(&bat_priv->mcast.want_lists_lock);
	476	+ hlist_add_head_rcu(&orig->mcast_want_all_unsnoopables_node,
	477	+ &bat_priv->mcast.want_all_unsnoopables_list);
	478	+ spin_unlock_bh(&bat_priv->mcast.want_lists_lock);
	479	+ /* switched from flag set to unset */
	480	+ } else if (!(mcast_flags & BATADV_MCAST_WANT_ALL_UNSNOOPABLES) &&
	481	+ orig->mcast_flags & BATADV_MCAST_WANT_ALL_UNSNOOPABLES) {
	482	+ atomic_dec(&bat_priv->mcast.num_want_all_unsnoopables);
	483	+
	484	+ spin_lock_bh(&bat_priv->mcast.want_lists_lock);
	485	+ hlist_del_rcu(&orig->mcast_want_all_unsnoopables_node);
	486	+ spin_unlock_bh(&bat_priv->mcast.want_lists_lock);
	487	+ }
	488	+}
	489	+
	490	+/**
376	491	* batadv_mcast_tvlv_ogm_handler_v1 - process incoming multicast tvlv container
377	492	* @bat_priv: the bat priv with all the soft interface information
378	493	* @orig: the orig_node of the ogm
...	...	@@ -416,6 +531,8 @@
416	531	(tvlv_value_len >= sizeof(mcast_flags)))
417	532	mcast_flags = (uint8_t )tvlv_value;
418	533
	534	+ batadv_mcast_want_unsnoop_update(bat_priv, orig, mcast_flags);
	535	+
419	536	orig->mcast_flags = mcast_flags;
420	537	}
421	538
...	...	@@ -452,5 +569,7 @@
452	569
453	570	if (!(orig->capabilities & BATADV_ORIG_CAPA_HAS_MCAST))
454	571	atomic_dec(&bat_priv->mcast.num_disabled);
	572	+
	573	+ batadv_mcast_want_unsnoop_update(bat_priv, orig, BATADV_NO_FLAGS);
455	574	}
...	...	@@ -89,6 +89,15 @@
89	89	BATADV_PARAMETER_PROBLEM = 12,
90	90	};
91	91
	92	+/**
	93	+ * enum batadv_mcast_flags - flags for multicast capabilities and settings
	94	+ * @BATADV_MCAST_WANT_ALL_UNSNOOPABLES: we want all packets destined for
	95	+ * 224.0.0.0/24 or ff02::1
	96	+ */
	97	+enum batadv_mcast_flags {
	98	+ BATADV_MCAST_WANT_ALL_UNSNOOPABLES = BIT(0),
	99	+};
	100	+
92	101	/* tt data subtypes */
93	102	#define BATADV_TT_DATA_TYPE_MASK 0x0F
94	103
...	...	@@ -710,6 +710,7 @@
710	710	bat_priv->mcast.flags = BATADV_NO_FLAGS;
711	711	atomic_set(&bat_priv->multicast_mode, 1);
712	712	atomic_set(&bat_priv->mcast.num_disabled, 0);
	713	+ atomic_set(&bat_priv->mcast.num_want_all_unsnoopables, 0);
713	714	#endif
714	715	atomic_set(&bat_priv->gw_mode, BATADV_GW_MODE_OFF);
715	716	atomic_set(&bat_priv->gw_sel_class, 20);
...	...	@@ -205,6 +205,8 @@
205	205	* @last_seen: time when last packet from this node was received
206	206	* @bcast_seqno_reset: time when the broadcast seqno window was reset
207	207	* @mcast_flags: multicast flags announced by the orig node
	208	+ * @mcast_want_all_unsnoop_node: a list node for the
	209	+ * mcast.want_all_unsnoopables list
208	210	* @capabilities: announced capabilities of this originator
209	211	* @capa_initialized: bitfield to remember whether a capability was initialized
210	212	* @last_ttvn: last seen translation table version number
...	...	@@ -249,6 +251,7 @@
249	251	unsigned long bcast_seqno_reset;
250	252	#ifdef CONFIG_BATMAN_ADV_MCAST
251	253	uint8_t mcast_flags;
	254	+ struct hlist_node mcast_want_all_unsnoopables_node;
252	255	#endif
253	256	uint8_t capabilities;
254	257	uint8_t capa_initialized;
255	258
256	259
257	260
...	...	@@ -619,15 +622,24 @@
619	622	/**
620	623	* struct batadv_priv_mcast - per mesh interface mcast data
621	624	* @mla_list: list of multicast addresses we are currently announcing via TT
	625	+ * @want_all_unsnoopables_list: a list of orig_nodes wanting all unsnoopable
	626	+ * multicast traffic
622	627	* @flags: the flags we have last sent in our mcast tvlv
623	628	* @enabled: whether the multicast tvlv is currently enabled
624	629	* @num_disabled: number of nodes that have no mcast tvlv
	630	+ * @num_want_all_unsnoopables: number of nodes wanting unsnoopable IP traffic
	631	+ * @want_lists_lock: lock for protecting modifications to mcast want lists
	632	+ * (traversals are rcu-locked)
625	633	*/
626	634	struct batadv_priv_mcast {
627	635	struct hlist_head mla_list;
	636	+ struct hlist_head want_all_unsnoopables_list;
628	637	uint8_t flags;
629	638	bool enabled;
630	639	atomic_t num_disabled;
	640	+ atomic_t num_want_all_unsnoopables;
	641	+ /* protects want_all_unsnoopables_list */
	642	+ spinlock_t want_lists_lock;
631	643	};
632	644	#endif
633	645