1 files changed, 660 insertions, 25 deletions

diff --git a/net/batman-adv/main.c b/net/batman-adv/main.c
index 1356af660b5b..3159a148c1ac 100644
--- a/net/batman-adv/main.c
+++ b/net/batman-adv/main.c
@@ -36,10 +36,11 @@
 #include "gateway_client.h"
 #include "bridge_loop_avoidance.h"
 #include "distributed-arp-table.h"
-#include "vis.h"
+#include "gateway_common.h"
 #include "hash.h"
 #include "bat_algo.h"
 #include "network-coding.h"
+#include "fragmentation.h"
 
 
 /* List manipulations on hardif_list have to be rtnl_lock()'ed,
@@ -109,9 +110,11 @@ int batadv_mesh_init(struct net_device *soft_iface)
 	spin_lock_init(&bat_priv->tt.req_list_lock);
 	spin_lock_init(&bat_priv->tt.roam_list_lock);
 	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);
-	spin_lock_init(&bat_priv->vis.hash_lock);
-	spin_lock_init(&bat_priv->vis.list_lock);
+	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);
 
 	INIT_HLIST_HEAD(&bat_priv->forw_bat_list);
 	INIT_HLIST_HEAD(&bat_priv->forw_bcast_list);
@@ -119,6 +122,9 @@ int batadv_mesh_init(struct net_device *soft_iface)
 	INIT_LIST_HEAD(&bat_priv->tt.changes_list);
 	INIT_LIST_HEAD(&bat_priv->tt.req_list);
 	INIT_LIST_HEAD(&bat_priv->tt.roam_list);
+	INIT_HLIST_HEAD(&bat_priv->tvlv.container_list);
+	INIT_HLIST_HEAD(&bat_priv->tvlv.handler_list);
+	INIT_HLIST_HEAD(&bat_priv->softif_vlan_list);
 
 	ret = batadv_originator_init(bat_priv);
 	if (ret < 0)
@@ -128,13 +134,6 @@ int batadv_mesh_init(struct net_device *soft_iface)
 	if (ret < 0)
 		goto err;
 
-	batadv_tt_local_add(soft_iface, soft_iface->dev_addr,
-			    BATADV_NULL_IFINDEX);
-
-	ret = batadv_vis_init(bat_priv);
-	if (ret < 0)
-		goto err;
-
 	ret = batadv_bla_init(bat_priv);
 	if (ret < 0)
 		goto err;
@@ -147,6 +146,8 @@ int batadv_mesh_init(struct net_device *soft_iface)
 	if (ret < 0)
 		goto err;
 
+	batadv_gw_init(bat_priv);
+
 	atomic_set(&bat_priv->gw.reselect, 0);
 	atomic_set(&bat_priv->mesh_state, BATADV_MESH_ACTIVE);
 
@@ -165,8 +166,6 @@ void batadv_mesh_free(struct net_device *soft_iface)
 
 	batadv_purge_outstanding_packets(bat_priv, NULL);
 
-	batadv_vis_quit(bat_priv);
-
 	batadv_gw_node_purge(bat_priv);
 	batadv_nc_mesh_free(bat_priv);
 	batadv_dat_free(bat_priv);
@@ -185,6 +184,8 @@ void batadv_mesh_free(struct net_device *soft_iface)
 	 */
 	batadv_originator_free(bat_priv);
 
+	batadv_gw_free(bat_priv);
+
 	free_percpu(bat_priv->bat_counters);
 	bat_priv->bat_counters = NULL;
 
@@ -255,6 +256,31 @@ out:
 }
 
 /**
+ * batadv_max_header_len - calculate maximum encapsulation overhead for a
+ *  payload packet
+ *
+ * Return the maximum encapsulation overhead in bytes.
+ */
+int batadv_max_header_len(void)
+{
+	int header_len = 0;
+
+	header_len = max_t(int, header_len,
+			   sizeof(struct batadv_unicast_packet));
+	header_len = max_t(int, header_len,
+			   sizeof(struct batadv_unicast_4addr_packet));
+	header_len = max_t(int, header_len,
+			   sizeof(struct batadv_bcast_packet));
+
+#ifdef CONFIG_BATMAN_ADV_NC
+	header_len = max_t(int, header_len,
+			   sizeof(struct batadv_coded_packet));
+#endif
+
+	return header_len;
+}
+
+/**
  * batadv_skb_set_priority - sets skb priority according to packet content
  * @skb: the packet to be sent
  * @offset: offset to the packet content
@@ -392,22 +418,31 @@ static void batadv_recv_handler_init(void)
 	for (i = 0; i < ARRAY_SIZE(batadv_rx_handler); i++)
 		batadv_rx_handler[i] = batadv_recv_unhandled_packet;
 
-	/* batman icmp packet */
-	batadv_rx_handler[BATADV_ICMP] = batadv_recv_icmp_packet;
+	for (i = BATADV_UNICAST_MIN; i <= BATADV_UNICAST_MAX; i++)
+		batadv_rx_handler[i] = batadv_recv_unhandled_unicast_packet;
+
+	/* compile time checks for struct member offsets */
+	BUILD_BUG_ON(offsetof(struct batadv_unicast_4addr_packet, src) != 10);
+	BUILD_BUG_ON(offsetof(struct batadv_unicast_packet, dest) != 4);
+	BUILD_BUG_ON(offsetof(struct batadv_unicast_tvlv_packet, dst) != 4);
+	BUILD_BUG_ON(offsetof(struct batadv_frag_packet, dest) != 4);
+	BUILD_BUG_ON(offsetof(struct batadv_icmp_packet, icmph.dst) != 4);
+	BUILD_BUG_ON(offsetof(struct batadv_icmp_packet_rr, icmph.dst) != 4);
+
+	/* broadcast packet */
+	batadv_rx_handler[BATADV_BCAST] = batadv_recv_bcast_packet;
+
+	/* unicast packets ... */
 	/* unicast with 4 addresses packet */
 	batadv_rx_handler[BATADV_UNICAST_4ADDR] = batadv_recv_unicast_packet;
 	/* unicast packet */
 	batadv_rx_handler[BATADV_UNICAST] = batadv_recv_unicast_packet;
-	/* fragmented unicast packet */
-	batadv_rx_handler[BATADV_UNICAST_FRAG] = batadv_recv_ucast_frag_packet;
-	/* broadcast packet */
-	batadv_rx_handler[BATADV_BCAST] = batadv_recv_bcast_packet;
-	/* vis packet */
-	batadv_rx_handler[BATADV_VIS] = batadv_recv_vis_packet;
-	/* Translation table query (request or response) */
-	batadv_rx_handler[BATADV_TT_QUERY] = batadv_recv_tt_query;
-	/* Roaming advertisement */
-	batadv_rx_handler[BATADV_ROAM_ADV] = batadv_recv_roam_adv;
+	/* unicast tvlv packet */
+	batadv_rx_handler[BATADV_UNICAST_TVLV] = batadv_recv_unicast_tvlv;
+	/* batman icmp packet */
+	batadv_rx_handler[BATADV_ICMP] = batadv_recv_icmp_packet;
+	/* Fragmented packets */
+	batadv_rx_handler[BATADV_UNICAST_FRAG] = batadv_recv_frag_packet;
 }
 
 int
@@ -415,7 +450,12 @@ batadv_recv_handler_register(uint8_t packet_type,
 			     int (*recv_handler)(struct sk_buff *,
 						 struct batadv_hard_iface *))
 {
-	if (batadv_rx_handler[packet_type] != &batadv_recv_unhandled_packet)
+	int (*curr)(struct sk_buff *,
+		    struct batadv_hard_iface *);
+	curr = batadv_rx_handler[packet_type];
+
+	if ((curr != batadv_recv_unhandled_packet) &&
+	    (curr != batadv_recv_unhandled_unicast_packet))
 		return -EBUSY;
 
 	batadv_rx_handler[packet_type] = recv_handler;
@@ -536,6 +576,601 @@ __be32 batadv_skb_crc32(struct sk_buff *skb, u8 *payload_ptr)
 	return htonl(crc);
 }
 
+/**
+ * batadv_tvlv_handler_free_ref - decrement the tvlv handler refcounter and
+ *  possibly free it
+ * @tvlv_handler: the tvlv handler to free
+ */
+static void
+batadv_tvlv_handler_free_ref(struct batadv_tvlv_handler *tvlv_handler)
+{
+	if (atomic_dec_and_test(&tvlv_handler->refcount))
+		kfree_rcu(tvlv_handler, rcu);
+}
+
+/**
+ * batadv_tvlv_handler_get - retrieve tvlv handler from the tvlv handler list
+ *  based on the provided type and version (both need to match)
+ * @bat_priv: the bat priv with all the soft interface information
+ * @type: tvlv handler type to look for
+ * @version: tvlv handler version to look for
+ *
+ * Returns tvlv handler if found or NULL otherwise.
+ */
+static struct batadv_tvlv_handler
+*batadv_tvlv_handler_get(struct batadv_priv *bat_priv,
+			 uint8_t type, uint8_t version)
+{
+	struct batadv_tvlv_handler *tvlv_handler_tmp, *tvlv_handler = NULL;
+
+	rcu_read_lock();
+	hlist_for_each_entry_rcu(tvlv_handler_tmp,
+				 &bat_priv->tvlv.handler_list, list) {
+		if (tvlv_handler_tmp->type != type)
+			continue;
+
+		if (tvlv_handler_tmp->version != version)
+			continue;
+
+		if (!atomic_inc_not_zero(&tvlv_handler_tmp->refcount))
+			continue;
+
+		tvlv_handler = tvlv_handler_tmp;
+		break;
+	}
+	rcu_read_unlock();
+
+	return tvlv_handler;
+}
+
+/**
+ * batadv_tvlv_container_free_ref - decrement the tvlv container refcounter and
+ *  possibly free it
+ * @tvlv_handler: the tvlv container to free
+ */
+static void batadv_tvlv_container_free_ref(struct batadv_tvlv_container *tvlv)
+{
+	if (atomic_dec_and_test(&tvlv->refcount))
+		kfree(tvlv);
+}
+
+/**
+ * batadv_tvlv_container_get - retrieve tvlv container from the tvlv container
+ *  list based on the provided type and version (both need to match)
+ * @bat_priv: the bat priv with all the soft interface information
+ * @type: tvlv container type to look for
+ * @version: tvlv container version to look for
+ *
+ * Has to be called with the appropriate locks being acquired
+ * (tvlv.container_list_lock).
+ *
+ * Returns tvlv container if found or NULL otherwise.
+ */
+static struct batadv_tvlv_container
+*batadv_tvlv_container_get(struct batadv_priv *bat_priv,
+			   uint8_t type, uint8_t version)
+{
+	struct batadv_tvlv_container *tvlv_tmp, *tvlv = NULL;
+
+	hlist_for_each_entry(tvlv_tmp, &bat_priv->tvlv.container_list, list) {
+		if (tvlv_tmp->tvlv_hdr.type != type)
+			continue;
+
+		if (tvlv_tmp->tvlv_hdr.version != version)
+			continue;
+
+		if (!atomic_inc_not_zero(&tvlv_tmp->refcount))
+			continue;
+
+		tvlv = tvlv_tmp;
+		break;
+	}
+
+	return tvlv;
+}
+
+/**
+ * batadv_tvlv_container_list_size - calculate the size of the tvlv container
+ *  list entries
+ * @bat_priv: the bat priv with all the soft interface information
+ *
+ * Has to be called with the appropriate locks being acquired
+ * (tvlv.container_list_lock).
+ *
+ * Returns size of all currently registered tvlv containers in bytes.
+ */
+static uint16_t batadv_tvlv_container_list_size(struct batadv_priv *bat_priv)
+{
+	struct batadv_tvlv_container *tvlv;
+	uint16_t tvlv_len = 0;
+
+	hlist_for_each_entry(tvlv, &bat_priv->tvlv.container_list, list) {
+		tvlv_len += sizeof(struct batadv_tvlv_hdr);
+		tvlv_len += ntohs(tvlv->tvlv_hdr.len);
+	}
+
+	return tvlv_len;
+}
+
+/**
+ * batadv_tvlv_container_remove - remove tvlv container from the tvlv container
+ *  list
+ * @tvlv: the to be removed tvlv container
+ *
+ * Has to be called with the appropriate locks being acquired
+ * (tvlv.container_list_lock).
+ */
+static void batadv_tvlv_container_remove(struct batadv_tvlv_container *tvlv)
+{
+	if (!tvlv)
+		return;
+
+	hlist_del(&tvlv->list);
+
+	/* first call to decrement the counter, second call to free */
+	batadv_tvlv_container_free_ref(tvlv);
+	batadv_tvlv_container_free_ref(tvlv);
+}
+
+/**
+ * batadv_tvlv_container_unregister - unregister tvlv container based on the
+ *  provided type and version (both need to match)
+ * @bat_priv: the bat priv with all the soft interface information
+ * @type: tvlv container type to unregister
+ * @version: tvlv container type to unregister
+ */
+void batadv_tvlv_container_unregister(struct batadv_priv *bat_priv,
+				      uint8_t type, uint8_t version)
+{
+	struct batadv_tvlv_container *tvlv;
+
+	spin_lock_bh(&bat_priv->tvlv.container_list_lock);
+	tvlv = batadv_tvlv_container_get(bat_priv, type, version);
+	batadv_tvlv_container_remove(tvlv);
+	spin_unlock_bh(&bat_priv->tvlv.container_list_lock);
+}
+
+/**
+ * batadv_tvlv_container_register - register tvlv type, version and content
+ *  to be propagated with each (primary interface) OGM
+ * @bat_priv: the bat priv with all the soft interface information
+ * @type: tvlv container type
+ * @version: tvlv container version
+ * @tvlv_value: tvlv container content
+ * @tvlv_value_len: tvlv container content length
+ *
+ * If a container of the same type and version was already registered the new
+ * content is going to replace the old one.
+ */
+void batadv_tvlv_container_register(struct batadv_priv *bat_priv,
+				    uint8_t type, uint8_t version,
+				    void *tvlv_value, uint16_t tvlv_value_len)
+{
+	struct batadv_tvlv_container *tvlv_old, *tvlv_new;
+
+	if (!tvlv_value)
+		tvlv_value_len = 0;
+
+	tvlv_new = kzalloc(sizeof(*tvlv_new) + tvlv_value_len, GFP_ATOMIC);
+	if (!tvlv_new)
+		return;
+
+	tvlv_new->tvlv_hdr.version = version;
+	tvlv_new->tvlv_hdr.type = type;
+	tvlv_new->tvlv_hdr.len = htons(tvlv_value_len);
+
+	memcpy(tvlv_new + 1, tvlv_value, ntohs(tvlv_new->tvlv_hdr.len));
+	INIT_HLIST_NODE(&tvlv_new->list);
+	atomic_set(&tvlv_new->refcount, 1);
+
+	spin_lock_bh(&bat_priv->tvlv.container_list_lock);
+	tvlv_old = batadv_tvlv_container_get(bat_priv, type, version);
+	batadv_tvlv_container_remove(tvlv_old);
+	hlist_add_head(&tvlv_new->list, &bat_priv->tvlv.container_list);
+	spin_unlock_bh(&bat_priv->tvlv.container_list_lock);
+}
+
+/**
+ * batadv_tvlv_realloc_packet_buff - reallocate packet buffer to accomodate
+ *  requested packet size
+ * @packet_buff: packet buffer
+ * @packet_buff_len: packet buffer size
+ * @packet_min_len: requested packet minimum size
+ * @additional_packet_len: requested additional packet size on top of minimum
+ *  size
+ *
+ * Returns true of the packet buffer could be changed to the requested size,
+ * false otherwise.
+ */
+static bool batadv_tvlv_realloc_packet_buff(unsigned char **packet_buff,
+					    int *packet_buff_len,
+					    int min_packet_len,
+					    int additional_packet_len)
+{
+	unsigned char *new_buff;
+
+	new_buff = kmalloc(min_packet_len + additional_packet_len, GFP_ATOMIC);
+
+	/* keep old buffer if kmalloc should fail */
+	if (new_buff) {
+		memcpy(new_buff, *packet_buff, min_packet_len);
+		kfree(*packet_buff);
+		*packet_buff = new_buff;
+		*packet_buff_len = min_packet_len + additional_packet_len;
+		return true;
+	}
+
+	return false;
+}
+
+/**
+ * batadv_tvlv_container_ogm_append - append tvlv container content to given
+ *  OGM packet buffer
+ * @bat_priv: the bat priv with all the soft interface information
+ * @packet_buff: ogm packet buffer
+ * @packet_buff_len: ogm packet buffer size including ogm header and tvlv
+ *  content
+ * @packet_min_len: ogm header size to be preserved for the OGM itself
+ *
+ * The ogm packet might be enlarged or shrunk depending on the current size
+ * and the size of the to-be-appended tvlv containers.
+ *
+ * Returns size of all appended tvlv containers in bytes.
+ */
+uint16_t batadv_tvlv_container_ogm_append(struct batadv_priv *bat_priv,
+					  unsigned char **packet_buff,
+					  int *packet_buff_len,
+					  int packet_min_len)
+{
+	struct batadv_tvlv_container *tvlv;
+	struct batadv_tvlv_hdr *tvlv_hdr;
+	uint16_t tvlv_value_len;
+	void *tvlv_value;
+	bool ret;
+
+	spin_lock_bh(&bat_priv->tvlv.container_list_lock);
+	tvlv_value_len = batadv_tvlv_container_list_size(bat_priv);
+
+	ret = batadv_tvlv_realloc_packet_buff(packet_buff, packet_buff_len,
+					      packet_min_len, tvlv_value_len);
+
+	if (!ret)
+		goto end;
+
+	if (!tvlv_value_len)
+		goto end;
+
+	tvlv_value = (*packet_buff) + packet_min_len;
+
+	hlist_for_each_entry(tvlv, &bat_priv->tvlv.container_list, list) {
+		tvlv_hdr = tvlv_value;
+		tvlv_hdr->type = tvlv->tvlv_hdr.type;
+		tvlv_hdr->version = tvlv->tvlv_hdr.version;
+		tvlv_hdr->len = tvlv->tvlv_hdr.len;
+		tvlv_value = tvlv_hdr + 1;
+		memcpy(tvlv_value, tvlv + 1, ntohs(tvlv->tvlv_hdr.len));
+		tvlv_value = (uint8_t *)tvlv_value + ntohs(tvlv->tvlv_hdr.len);
+	}
+
+end:
+	spin_unlock_bh(&bat_priv->tvlv.container_list_lock);
+	return tvlv_value_len;
+}
+
+/**
+ * batadv_tvlv_call_handler - parse the given tvlv buffer to call the
+ *  appropriate handlers
+ * @bat_priv: the bat priv with all the soft interface information
+ * @tvlv_handler: tvlv callback function handling the tvlv content
+ * @ogm_source: flag indicating wether the tvlv is an ogm or a unicast packet
+ * @orig_node: orig node emitting the ogm packet
+ * @src: source mac address of the unicast packet
+ * @dst: destination mac address of the unicast packet
+ * @tvlv_value: tvlv content
+ * @tvlv_value_len: tvlv content length
+ *
+ * Returns success if handler was not found or the return value of the handler
+ * callback.
+ */
+static int batadv_tvlv_call_handler(struct batadv_priv *bat_priv,
+				    struct batadv_tvlv_handler *tvlv_handler,
+				    bool ogm_source,
+				    struct batadv_orig_node *orig_node,
+				    uint8_t *src, uint8_t *dst,
+				    void *tvlv_value, uint16_t tvlv_value_len)
+{
+	if (!tvlv_handler)
+		return NET_RX_SUCCESS;
+
+	if (ogm_source) {
+		if (!tvlv_handler->ogm_handler)
+			return NET_RX_SUCCESS;
+
+		if (!orig_node)
+			return NET_RX_SUCCESS;
+
+		tvlv_handler->ogm_handler(bat_priv, orig_node,
+					  BATADV_NO_FLAGS,
+					  tvlv_value, tvlv_value_len);
+		tvlv_handler->flags |= BATADV_TVLV_HANDLER_OGM_CALLED;
+	} else {
+		if (!src)
+			return NET_RX_SUCCESS;
+
+		if (!dst)
+			return NET_RX_SUCCESS;
+
+		if (!tvlv_handler->unicast_handler)
+			return NET_RX_SUCCESS;
+
+		return tvlv_handler->unicast_handler(bat_priv, src,
+						     dst, tvlv_value,
+						     tvlv_value_len);
+	}
+
+	return NET_RX_SUCCESS;
+}
+
+/**
+ * batadv_tvlv_containers_process - parse the given tvlv buffer to call the
+ *  appropriate handlers
+ * @bat_priv: the bat priv with all the soft interface information
+ * @ogm_source: flag indicating wether the tvlv is an ogm or a unicast packet
+ * @orig_node: orig node emitting the ogm packet
+ * @src: source mac address of the unicast packet
+ * @dst: destination mac address of the unicast packet
+ * @tvlv_value: tvlv content
+ * @tvlv_value_len: tvlv content length
+ *
+ * Returns success when processing an OGM or the return value of all called
+ * handler callbacks.
+ */
+int batadv_tvlv_containers_process(struct batadv_priv *bat_priv,
+				   bool ogm_source,
+				   struct batadv_orig_node *orig_node,
+				   uint8_t *src, uint8_t *dst,
+				   void *tvlv_value, uint16_t tvlv_value_len)
+{
+	struct batadv_tvlv_handler *tvlv_handler;
+	struct batadv_tvlv_hdr *tvlv_hdr;
+	uint16_t tvlv_value_cont_len;
+	uint8_t cifnotfound = BATADV_TVLV_HANDLER_OGM_CIFNOTFND;
+	int ret = NET_RX_SUCCESS;
+
+	while (tvlv_value_len >= sizeof(*tvlv_hdr)) {
+		tvlv_hdr = tvlv_value;
+		tvlv_value_cont_len = ntohs(tvlv_hdr->len);
+		tvlv_value = tvlv_hdr + 1;
+		tvlv_value_len -= sizeof(*tvlv_hdr);
+
+		if (tvlv_value_cont_len > tvlv_value_len)
+			break;
+
+		tvlv_handler = batadv_tvlv_handler_get(bat_priv,
+						       tvlv_hdr->type,
+						       tvlv_hdr->version);
+
+		ret |= batadv_tvlv_call_handler(bat_priv, tvlv_handler,
+						ogm_source, orig_node,
+						src, dst, tvlv_value,
+						tvlv_value_cont_len);
+		if (tvlv_handler)
+			batadv_tvlv_handler_free_ref(tvlv_handler);
+		tvlv_value = (uint8_t *)tvlv_value + tvlv_value_cont_len;
+		tvlv_value_len -= tvlv_value_cont_len;
+	}
+
+	if (!ogm_source)
+		return ret;
+
+	rcu_read_lock();
+	hlist_for_each_entry_rcu(tvlv_handler,
+				 &bat_priv->tvlv.handler_list, list) {
+		if ((tvlv_handler->flags & BATADV_TVLV_HANDLER_OGM_CIFNOTFND) &&
+		    !(tvlv_handler->flags & BATADV_TVLV_HANDLER_OGM_CALLED))
+			tvlv_handler->ogm_handler(bat_priv, orig_node,
+						  cifnotfound, NULL, 0);
+
+		tvlv_handler->flags &= ~BATADV_TVLV_HANDLER_OGM_CALLED;
+	}
+	rcu_read_unlock();
+
+	return NET_RX_SUCCESS;
+}
+
+/**
+ * batadv_tvlv_ogm_receive - process an incoming ogm and call the appropriate
+ *  handlers
+ * @bat_priv: the bat priv with all the soft interface information
+ * @batadv_ogm_packet: ogm packet containing the tvlv containers
+ * @orig_node: orig node emitting the ogm packet
+ */
+void batadv_tvlv_ogm_receive(struct batadv_priv *bat_priv,
+			     struct batadv_ogm_packet *batadv_ogm_packet,
+			     struct batadv_orig_node *orig_node)
+{
+	void *tvlv_value;
+	uint16_t tvlv_value_len;
+
+	if (!batadv_ogm_packet)
+		return;
+
+	tvlv_value_len = ntohs(batadv_ogm_packet->tvlv_len);
+	if (!tvlv_value_len)
+		return;
+
+	tvlv_value = batadv_ogm_packet + 1;
+
+	batadv_tvlv_containers_process(bat_priv, true, orig_node, NULL, NULL,
+				       tvlv_value, tvlv_value_len);
+}
+
+/**
+ * batadv_tvlv_handler_register - register tvlv handler based on the provided
+ *  type and version (both need to match) for ogm tvlv payload and/or unicast
+ *  payload
+ * @bat_priv: the bat priv with all the soft interface information
+ * @optr: ogm tvlv handler callback function. This function receives the orig
+ *  node, flags and the tvlv content as argument to process.
+ * @uptr: unicast tvlv handler callback function. This function receives the
+ *  source & destination of the unicast packet as well as the tvlv content
+ *  to process.
+ * @type: tvlv handler type to be registered
+ * @version: tvlv handler version to be registered
+ * @flags: flags to enable or disable TVLV API behavior
+ */
+void batadv_tvlv_handler_register(struct batadv_priv *bat_priv,
+				  void (*optr)(struct batadv_priv *bat_priv,
+					       struct batadv_orig_node *orig,
+					       uint8_t flags,
+					       void *tvlv_value,
+					       uint16_t tvlv_value_len),
+				  int (*uptr)(struct batadv_priv *bat_priv,
+					      uint8_t *src, uint8_t *dst,
+					      void *tvlv_value,
+					      uint16_t tvlv_value_len),
+				  uint8_t type, uint8_t version, uint8_t flags)
+{
+	struct batadv_tvlv_handler *tvlv_handler;
+
+	tvlv_handler = batadv_tvlv_handler_get(bat_priv, type, version);
+	if (tvlv_handler) {
+		batadv_tvlv_handler_free_ref(tvlv_handler);
+		return;
+	}
+
+	tvlv_handler = kzalloc(sizeof(*tvlv_handler), GFP_ATOMIC);
+	if (!tvlv_handler)
+		return;
+
+	tvlv_handler->ogm_handler = optr;
+	tvlv_handler->unicast_handler = uptr;
+	tvlv_handler->type = type;
+	tvlv_handler->version = version;
+	tvlv_handler->flags = flags;
+	atomic_set(&tvlv_handler->refcount, 1);
+	INIT_HLIST_NODE(&tvlv_handler->list);
+
+	spin_lock_bh(&bat_priv->tvlv.handler_list_lock);
+	hlist_add_head_rcu(&tvlv_handler->list, &bat_priv->tvlv.handler_list);
+	spin_unlock_bh(&bat_priv->tvlv.handler_list_lock);
+}
+
+/**
+ * batadv_tvlv_handler_unregister - unregister tvlv handler based on the
+ *  provided type and version (both need to match)
+ * @bat_priv: the bat priv with all the soft interface information
+ * @type: tvlv handler type to be unregistered
+ * @version: tvlv handler version to be unregistered
+ */
+void batadv_tvlv_handler_unregister(struct batadv_priv *bat_priv,
+				    uint8_t type, uint8_t version)
+{
+	struct batadv_tvlv_handler *tvlv_handler;
+
+	tvlv_handler = batadv_tvlv_handler_get(bat_priv, type, version);
+	if (!tvlv_handler)
+		return;
+
+	batadv_tvlv_handler_free_ref(tvlv_handler);
+	spin_lock_bh(&bat_priv->tvlv.handler_list_lock);
+	hlist_del_rcu(&tvlv_handler->list);
+	spin_unlock_bh(&bat_priv->tvlv.handler_list_lock);
+	batadv_tvlv_handler_free_ref(tvlv_handler);
+}
+
+/**
+ * batadv_tvlv_unicast_send - send a unicast packet with tvlv payload to the
+ *  specified host
+ * @bat_priv: the bat priv with all the soft interface information
+ * @src: source mac address of the unicast packet
+ * @dst: destination mac address of the unicast packet
+ * @type: tvlv type
+ * @version: tvlv version
+ * @tvlv_value: tvlv content
+ * @tvlv_value_len: tvlv content length
+ */
+void batadv_tvlv_unicast_send(struct batadv_priv *bat_priv, uint8_t *src,
+			      uint8_t *dst, uint8_t type, uint8_t version,
+			      void *tvlv_value, uint16_t tvlv_value_len)
+{
+	struct batadv_unicast_tvlv_packet *unicast_tvlv_packet;
+	struct batadv_tvlv_hdr *tvlv_hdr;
+	struct batadv_orig_node *orig_node;
+	struct sk_buff *skb = NULL;
+	unsigned char *tvlv_buff;
+	unsigned int tvlv_len;
+	ssize_t hdr_len = sizeof(*unicast_tvlv_packet);
+	bool ret = false;
+
+	orig_node = batadv_orig_hash_find(bat_priv, dst);
+	if (!orig_node)
+		goto out;
+
+	tvlv_len = sizeof(*tvlv_hdr) + tvlv_value_len;
+
+	skb = netdev_alloc_skb_ip_align(NULL, ETH_HLEN + hdr_len + tvlv_len);
+	if (!skb)
+		goto out;
+
+	skb->priority = TC_PRIO_CONTROL;
+	skb_reserve(skb, ETH_HLEN);
+	tvlv_buff = skb_put(skb, sizeof(*unicast_tvlv_packet) + tvlv_len);
+	unicast_tvlv_packet = (struct batadv_unicast_tvlv_packet *)tvlv_buff;
+	unicast_tvlv_packet->header.packet_type = BATADV_UNICAST_TVLV;
+	unicast_tvlv_packet->header.version = BATADV_COMPAT_VERSION;
+	unicast_tvlv_packet->header.ttl = BATADV_TTL;
+	unicast_tvlv_packet->reserved = 0;
+	unicast_tvlv_packet->tvlv_len = htons(tvlv_len);
+	unicast_tvlv_packet->align = 0;
+	memcpy(unicast_tvlv_packet->src, src, ETH_ALEN);
+	memcpy(unicast_tvlv_packet->dst, dst, ETH_ALEN);
+
+	tvlv_buff = (unsigned char *)(unicast_tvlv_packet + 1);
+	tvlv_hdr = (struct batadv_tvlv_hdr *)tvlv_buff;
+	tvlv_hdr->version = version;
+	tvlv_hdr->type = type;
+	tvlv_hdr->len = htons(tvlv_value_len);
+	tvlv_buff += sizeof(*tvlv_hdr);
+	memcpy(tvlv_buff, tvlv_value, tvlv_value_len);
+
+	if (batadv_send_skb_to_orig(skb, orig_node, NULL) != NET_XMIT_DROP)
+		ret = true;
+
+out:
+	if (skb && !ret)
+		kfree_skb(skb);
+	if (orig_node)
+		batadv_orig_node_free_ref(orig_node);
+}
+
+/**
+ * batadv_get_vid - extract the VLAN identifier from skb if any
+ * @skb: the buffer containing the packet
+ * @header_len: length of the batman header preceding the ethernet header
+ *
+ * If the packet embedded in the skb is vlan tagged this function returns the
+ * VID with the BATADV_VLAN_HAS_TAG flag. Otherwise BATADV_NO_FLAGS is returned.
+ */
+unsigned short batadv_get_vid(struct sk_buff *skb, size_t header_len)
+{
+	struct ethhdr *ethhdr = (struct ethhdr *)(skb->data + header_len);
+	struct vlan_ethhdr *vhdr;
+	unsigned short vid;
+
+	if (ethhdr->h_proto != htons(ETH_P_8021Q))
+		return BATADV_NO_FLAGS;
+
+	if (!pskb_may_pull(skb, header_len + VLAN_ETH_HLEN))
+		return BATADV_NO_FLAGS;
+
+	vhdr = (struct vlan_ethhdr *)(skb->data + header_len);
+	vid = ntohs(vhdr->h_vlan_TCI) & VLAN_VID_MASK;
+	vid |= BATADV_VLAN_HAS_TAG;
+
+	return vid;
+}
+
 static int batadv_param_set_ra(const char *val, const struct kernel_param *kp)
 {
 	struct batadv_algo_ops *bat_algo_ops;