Merge git://git.kernel.org/pub/scm/linux/kernel/git/davem/net-next

Pull networking changes from David Miller:

1) Allow to dump, monitor, and change the bridge multicast database
   using netlink.  From Cong Wang.

2) RFC 5961 TCP blind data injection attack mitigation, from Eric
   Dumazet.

3) Networking user namespace support from Eric W. Biederman.

4) tuntap/virtio-net multiqueue support by Jason Wang.

5) Support for checksum offload of encapsulated packets (basically,
   tunneled traffic can still be checksummed by HW).  From Joseph
   Gasparakis.

6) Allow BPF filter access to VLAN tags, from Eric Dumazet and
   Daniel Borkmann.

7) Bridge port parameters over netlink and BPDU blocking support
   from Stephen Hemminger.

8) Improve data access patterns during inet socket demux by rearranging
   socket layout, from Eric Dumazet.

9) TIPC protocol updates and cleanups from Ying Xue, Paul Gortmaker, and
   Jon Maloy.

10) Update TCP socket hash sizing to be more in line with current day
    realities.  The existing heurstics were choosen a decade ago.
    From Eric Dumazet.

11) Fix races, queue bloat, and excessive wakeups in ATM and
    associated drivers, from Krzysztof Mazur and David Woodhouse.

12) Support DOVE (Distributed Overlay Virtual Ethernet) extensions
    in VXLAN driver, from David Stevens.

13) Add "oops_only" mode to netconsole, from Amerigo Wang.

14) Support set and query of VEB/VEPA bridge mode via PF_BRIDGE, also
    allow DCB netlink to work on namespaces other than the initial
    namespace.  From John Fastabend.

15) Support PTP in the Tigon3 driver, from Matt Carlson.

16) tun/vhost zero copy fixes and improvements, plus turn it on
    by default, from Michael S. Tsirkin.

17) Support per-association statistics in SCTP, from Michele
    Baldessari.

And many, many, driver updates, cleanups, and improvements.  Too
numerous to mention individually.

* git://git.kernel.org/pub/scm/linux/kernel/git/davem/net-next: (1722 commits)
  net/mlx4_en: Add support for destination MAC in steering rules
  net/mlx4_en: Use generic etherdevice.h functions.
  net: ethtool: Add destination MAC address to flow steering API
  bridge: add support of adding and deleting mdb entries
  bridge: notify mdb changes via netlink
  ndisc: Unexport ndisc_{build,send}_skb().
  uapi: add missing netconf.h to export list
  pkt_sched: avoid requeues if possible
  solos-pci: fix double-free of TX skb in DMA mode
  bnx2: Fix accidental reversions.
  bna: Driver Version Updated to 3.1.2.1
  bna: Firmware update
  bna: Add RX State
  bna: Rx Page Based Allocation
  bna: TX Intr Coalescing Fix
  bna: Tx and Rx Optimizations
  bna: Code Cleanup and Enhancements
  ath9k: check pdata variable before dereferencing it
  ath5k: RX timestamp is reported at end of frame
  ath9k_htc: RX timestamp is reported at end of frame
  ...

28 files changed, 2582 insertions, 647 deletions

diff --git a/net/batman-adv/Kconfig b/net/batman-adv/Kconfig
index 53f5244e28f8..8d8afb134b3a 100644
--- a/net/batman-adv/Kconfig
+++ b/net/batman-adv/Kconfig
@@ -6,6 +6,7 @@ config BATMAN_ADV
 	tristate "B.A.T.M.A.N. Advanced Meshing Protocol"
 	depends on NET
 	select CRC16
+	select LIBCRC32C
         default n
 	help
           B.A.T.M.A.N. (better approach to mobile ad-hoc networking) is
@@ -25,6 +26,16 @@ config BATMAN_ADV_BLA
 	  more than one mesh node in the same LAN, you can safely remove
 	  this feature and save some space.
 
+config BATMAN_ADV_DAT
+	bool "Distributed ARP Table"
+	depends on BATMAN_ADV && INET
+	default n
+	help
+	  This option enables DAT (Distributed ARP Table), a DHT based
+	  mechanism that increases ARP reliability on sparse wireless
+	  mesh networks. If you think that your network does not need
+	  this option you can safely remove it and save some space.
+
 config BATMAN_ADV_DEBUG
 	bool "B.A.T.M.A.N. debugging"
 	depends on BATMAN_ADV
diff --git a/net/batman-adv/Makefile b/net/batman-adv/Makefile
index 8676d2b1d574..e45e3b4e32e3 100644
--- a/net/batman-adv/Makefile
+++ b/net/batman-adv/Makefile
@@ -23,6 +23,7 @@ batman-adv-y += bat_iv_ogm.o
 batman-adv-y += bitarray.o
 batman-adv-$(CONFIG_BATMAN_ADV_BLA) += bridge_loop_avoidance.o
 batman-adv-y += debugfs.o
+batman-adv-$(CONFIG_BATMAN_ADV_DAT) += distributed-arp-table.o
 batman-adv-y += gateway_client.o
 batman-adv-y += gateway_common.o
 batman-adv-y += hard-interface.o
diff --git a/net/batman-adv/bat_iv_ogm.c b/net/batman-adv/bat_iv_ogm.c
index b02b75dae3a8..9f3925a85aab 100644
--- a/net/batman-adv/bat_iv_ogm.c
+++ b/net/batman-adv/bat_iv_ogm.c
@@ -57,20 +57,22 @@ out:
 static int batadv_iv_ogm_iface_enable(struct batadv_hard_iface *hard_iface)
 {
 	struct batadv_ogm_packet *batadv_ogm_packet;
+	unsigned char *ogm_buff;
 	uint32_t random_seqno;
 	int res = -ENOMEM;
 
 	/* randomize initial seqno to avoid collision */
 	get_random_bytes(&random_seqno, sizeof(random_seqno));
-	atomic_set(&hard_iface->seqno, random_seqno);
+	atomic_set(&hard_iface->bat_iv.ogm_seqno, random_seqno);
 
-	hard_iface->packet_len = BATADV_OGM_HLEN;
-	hard_iface->packet_buff = kmalloc(hard_iface->packet_len, GFP_ATOMIC);
-
-	if (!hard_iface->packet_buff)
+	hard_iface->bat_iv.ogm_buff_len = BATADV_OGM_HLEN;
+	ogm_buff = kmalloc(hard_iface->bat_iv.ogm_buff_len, GFP_ATOMIC);
+	if (!ogm_buff)
 		goto out;
 
-	batadv_ogm_packet = (struct batadv_ogm_packet *)hard_iface->packet_buff;
+	hard_iface->bat_iv.ogm_buff = ogm_buff;
+
+	batadv_ogm_packet = (struct batadv_ogm_packet *)ogm_buff;
 	batadv_ogm_packet->header.packet_type = BATADV_IV_OGM;
 	batadv_ogm_packet->header.version = BATADV_COMPAT_VERSION;
 	batadv_ogm_packet->header.ttl = 2;
@@ -87,15 +89,16 @@ out:
 
 static void batadv_iv_ogm_iface_disable(struct batadv_hard_iface *hard_iface)
 {
-	kfree(hard_iface->packet_buff);
-	hard_iface->packet_buff = NULL;
+	kfree(hard_iface->bat_iv.ogm_buff);
+	hard_iface->bat_iv.ogm_buff = NULL;
 }
 
 static void batadv_iv_ogm_iface_update_mac(struct batadv_hard_iface *hard_iface)
 {
 	struct batadv_ogm_packet *batadv_ogm_packet;
+	unsigned char *ogm_buff = hard_iface->bat_iv.ogm_buff;
 
-	batadv_ogm_packet = (struct batadv_ogm_packet *)hard_iface->packet_buff;
+	batadv_ogm_packet = (struct batadv_ogm_packet *)ogm_buff;
 	memcpy(batadv_ogm_packet->orig,
 	       hard_iface->net_dev->dev_addr, ETH_ALEN);
 	memcpy(batadv_ogm_packet->prev_sender,
@@ -106,8 +109,9 @@ static void
 batadv_iv_ogm_primary_iface_set(struct batadv_hard_iface *hard_iface)
 {
 	struct batadv_ogm_packet *batadv_ogm_packet;
+	unsigned char *ogm_buff = hard_iface->bat_iv.ogm_buff;
 
-	batadv_ogm_packet = (struct batadv_ogm_packet *)hard_iface->packet_buff;
+	batadv_ogm_packet = (struct batadv_ogm_packet *)ogm_buff;
 	batadv_ogm_packet->flags = BATADV_PRIMARIES_FIRST_HOP;
 	batadv_ogm_packet->header.ttl = BATADV_TTL;
 }
@@ -407,9 +411,11 @@ static void batadv_iv_ogm_aggregate_new(const unsigned char *packet_buff,
 
 	if ((atomic_read(&bat_priv->aggregated_ogms)) &&
 	    (packet_len < BATADV_MAX_AGGREGATION_BYTES))
-		skb_size = BATADV_MAX_AGGREGATION_BYTES + ETH_HLEN;
+		skb_size = BATADV_MAX_AGGREGATION_BYTES;
 	else
-		skb_size = packet_len + ETH_HLEN;
+		skb_size = packet_len;
+
+	skb_size += ETH_HLEN + NET_IP_ALIGN;
 
 	forw_packet_aggr->skb = dev_alloc_skb(skb_size);
 	if (!forw_packet_aggr->skb) {
@@ -418,7 +424,7 @@ static void batadv_iv_ogm_aggregate_new(const unsigned char *packet_buff,
 		kfree(forw_packet_aggr);
 		goto out;
 	}
-	skb_reserve(forw_packet_aggr->skb, ETH_HLEN);
+	skb_reserve(forw_packet_aggr->skb, ETH_HLEN + NET_IP_ALIGN);
 
 	INIT_HLIST_NODE(&forw_packet_aggr->list);
 
@@ -590,8 +596,10 @@ static void batadv_iv_ogm_forward(struct batadv_orig_node *orig_node,
 static void batadv_iv_ogm_schedule(struct batadv_hard_iface *hard_iface)
 {
 	struct batadv_priv *bat_priv = netdev_priv(hard_iface->soft_iface);
+	unsigned char **ogm_buff = &hard_iface->bat_iv.ogm_buff;
 	struct batadv_ogm_packet *batadv_ogm_packet;
 	struct batadv_hard_iface *primary_if;
+	int *ogm_buff_len = &hard_iface->bat_iv.ogm_buff_len;
 	int vis_server, tt_num_changes = 0;
 	uint32_t seqno;
 	uint8_t bandwidth;
@@ -600,17 +608,16 @@ static void batadv_iv_ogm_schedule(struct batadv_hard_iface *hard_iface)
 	primary_if = batadv_primary_if_get_selected(bat_priv);
 
 	if (hard_iface == primary_if)
-		tt_num_changes = batadv_tt_append_diff(bat_priv,
-						       &hard_iface->packet_buff,
-						       &hard_iface->packet_len,
+		tt_num_changes = batadv_tt_append_diff(bat_priv, ogm_buff,
+						       ogm_buff_len,
 						       BATADV_OGM_HLEN);
 
-	batadv_ogm_packet = (struct batadv_ogm_packet *)hard_iface->packet_buff;
+	batadv_ogm_packet = (struct batadv_ogm_packet *)(*ogm_buff);
 
 	/* change sequence number to network order */
-	seqno = (uint32_t)atomic_read(&hard_iface->seqno);
+	seqno = (uint32_t)atomic_read(&hard_iface->bat_iv.ogm_seqno);
 	batadv_ogm_packet->seqno = htonl(seqno);
-	atomic_inc(&hard_iface->seqno);
+	atomic_inc(&hard_iface->bat_iv.ogm_seqno);
 
 	batadv_ogm_packet->ttvn = atomic_read(&bat_priv->tt.vn);
 	batadv_ogm_packet->tt_crc = htons(bat_priv->tt.local_crc);
@@ -631,8 +638,8 @@ static void batadv_iv_ogm_schedule(struct batadv_hard_iface *hard_iface)
 	}
 
 	batadv_slide_own_bcast_window(hard_iface);
-	batadv_iv_ogm_queue_add(bat_priv, hard_iface->packet_buff,
-				hard_iface->packet_len, hard_iface, 1,
+	batadv_iv_ogm_queue_add(bat_priv, hard_iface->bat_iv.ogm_buff,
+				hard_iface->bat_iv.ogm_buff_len, hard_iface, 1,
 				batadv_iv_ogm_emit_send_time(bat_priv));
 
 	if (primary_if)
@@ -1015,7 +1022,7 @@ static void batadv_iv_ogm_process(const struct ethhdr *ethhdr,
 		return;
 
 	/* could be changed by schedule_own_packet() */
-	if_incoming_seqno = atomic_read(&if_incoming->seqno);
+	if_incoming_seqno = atomic_read(&if_incoming->bat_iv.ogm_seqno);
 
 	if (batadv_ogm_packet->flags & BATADV_DIRECTLINK)
 		has_directlink_flag = 1;
diff --git a/net/batman-adv/bitarray.c b/net/batman-adv/bitarray.c
index aea174cdbfbd..5453b17d8df2 100644
--- a/net/batman-adv/bitarray.c
+++ b/net/batman-adv/bitarray.c
@@ -79,20 +79,17 @@ int batadv_bit_get_packet(void *priv, unsigned long *seq_bits,
 	 * or the old packet got delayed somewhere in the network. The
 	 * packet should be dropped without calling this function if the
 	 * seqno window is protected.
+	 *
+	 * seq_num_diff <= -BATADV_TQ_LOCAL_WINDOW_SIZE
+	 * or
+	 * seq_num_diff >= BATADV_EXPECTED_SEQNO_RANGE
 	 */
-	if (seq_num_diff <= -BATADV_TQ_LOCAL_WINDOW_SIZE ||
-	    seq_num_diff >= BATADV_EXPECTED_SEQNO_RANGE) {
+	batadv_dbg(BATADV_DBG_BATMAN, bat_priv,
+		   "Other host probably restarted!\n");
 
-		batadv_dbg(BATADV_DBG_BATMAN, bat_priv,
-			   "Other host probably restarted!\n");
-
-		bitmap_zero(seq_bits, BATADV_TQ_LOCAL_WINDOW_SIZE);
-		if (set_mark)
-			batadv_set_bit(seq_bits, 0);
-
-		return 1;
-	}
+	bitmap_zero(seq_bits, BATADV_TQ_LOCAL_WINDOW_SIZE);
+	if (set_mark)
+		batadv_set_bit(seq_bits, 0);
 
-	/* never reached */
-	return 0;
+	return 1;
 }
diff --git a/net/batman-adv/bridge_loop_avoidance.c b/net/batman-adv/bridge_loop_avoidance.c
index fd8d5afec0dd..5aebe9327d68 100644
--- a/net/batman-adv/bridge_loop_avoidance.c
+++ b/net/batman-adv/bridge_loop_avoidance.c
@@ -40,15 +40,11 @@ static void batadv_bla_send_announce(struct batadv_priv *bat_priv,
 /* return the index of the claim */
 static inline uint32_t batadv_choose_claim(const void *data, uint32_t size)
 {
-	const unsigned char *key = data;
+	struct batadv_claim *claim = (struct batadv_claim *)data;
 	uint32_t hash = 0;
-	size_t i;
 
-	for (i = 0; i < ETH_ALEN + sizeof(short); i++) {
-		hash += key[i];
-		hash += (hash << 10);
-		hash ^= (hash >> 6);
-	}
+	hash = batadv_hash_bytes(hash, &claim->addr, sizeof(claim->addr));
+	hash = batadv_hash_bytes(hash, &claim->vid, sizeof(claim->vid));
 
 	hash += (hash << 3);
 	hash ^= (hash >> 11);
@@ -61,15 +57,11 @@ static inline uint32_t batadv_choose_claim(const void *data, uint32_t size)
 static inline uint32_t batadv_choose_backbone_gw(const void *data,
 						 uint32_t size)
 {
-	const unsigned char *key = data;
+	struct batadv_claim *claim = (struct batadv_claim *)data;
 	uint32_t hash = 0;
-	size_t i;
 
-	for (i = 0; i < ETH_ALEN + sizeof(short); i++) {
-		hash += key[i];
-		hash += (hash << 10);
-		hash ^= (hash >> 6);
-	}
+	hash = batadv_hash_bytes(hash, &claim->addr, sizeof(claim->addr));
+	hash = batadv_hash_bytes(hash, &claim->vid, sizeof(claim->vid));
 
 	hash += (hash << 3);
 	hash ^= (hash >> 11);
@@ -85,8 +77,15 @@ static int batadv_compare_backbone_gw(const struct hlist_node *node,
 {
 	const void *data1 = container_of(node, struct batadv_backbone_gw,
 					 hash_entry);
+	const struct batadv_backbone_gw *gw1 = data1, *gw2 = data2;
+
+	if (!batadv_compare_eth(gw1->orig, gw2->orig))
+		return 0;
+
+	if (gw1->vid != gw2->vid)
+		return 0;
 
-	return (memcmp(data1, data2, ETH_ALEN + sizeof(short)) == 0 ? 1 : 0);
+	return 1;
 }
 
 /* compares address and vid of two claims */
@@ -95,8 +94,15 @@ static int batadv_compare_claim(const struct hlist_node *node,
 {
 	const void *data1 = container_of(node, struct batadv_claim,
 					 hash_entry);
+	const struct batadv_claim *cl1 = data1, *cl2 = data2;
+
+	if (!batadv_compare_eth(cl1->addr, cl2->addr))
+		return 0;
+
+	if (cl1->vid != cl2->vid)
+		return 0;
 
-	return (memcmp(data1, data2, ETH_ALEN + sizeof(short)) == 0 ? 1 : 0);
+	return 1;
 }
 
 /* free a backbone gw */
@@ -362,7 +368,7 @@ out:
  */
 static struct batadv_backbone_gw *
 batadv_bla_get_backbone_gw(struct batadv_priv *bat_priv, uint8_t *orig,
-			   short vid)
+			   short vid, bool own_backbone)
 {
 	struct batadv_backbone_gw *entry;
 	struct batadv_orig_node *orig_node;
@@ -386,6 +392,7 @@ batadv_bla_get_backbone_gw(struct batadv_priv *bat_priv, uint8_t *orig,
 	entry->crc = BATADV_BLA_CRC_INIT;
 	entry->bat_priv = bat_priv;
 	atomic_set(&entry->request_sent, 0);
+	atomic_set(&entry->wait_periods, 0);
 	memcpy(entry->orig, orig, ETH_ALEN);
 
 	/* one for the hash, one for returning */
@@ -409,6 +416,16 @@ batadv_bla_get_backbone_gw(struct batadv_priv *bat_priv, uint8_t *orig,
 					  "became a backbone gateway");
 		batadv_orig_node_free_ref(orig_node);
 	}
+
+	if (own_backbone) {
+		batadv_bla_send_announce(bat_priv, entry);
+
+		/* this will be decreased in the worker thread */
+		atomic_inc(&entry->request_sent);
+		atomic_set(&entry->wait_periods, BATADV_BLA_WAIT_PERIODS);
+		atomic_inc(&bat_priv->bla.num_requests);
+	}
+
 	return entry;
 }
 
@@ -424,7 +441,7 @@ batadv_bla_update_own_backbone_gw(struct batadv_priv *bat_priv,
 
 	backbone_gw = batadv_bla_get_backbone_gw(bat_priv,
 						 primary_if->net_dev->dev_addr,
-						 vid);
+						 vid, true);
 	if (unlikely(!backbone_gw))
 		return;
 
@@ -632,7 +649,8 @@ static int batadv_handle_announce(struct batadv_priv *bat_priv,
 	if (memcmp(an_addr, batadv_announce_mac, 4) != 0)
 		return 0;
 
-	backbone_gw = batadv_bla_get_backbone_gw(bat_priv, backbone_addr, vid);
+	backbone_gw = batadv_bla_get_backbone_gw(bat_priv, backbone_addr, vid,
+						 false);
 
 	if (unlikely(!backbone_gw))
 		return 1;
@@ -730,7 +748,8 @@ static int batadv_handle_claim(struct batadv_priv *bat_priv,
 
 	/* register the gateway if not yet available, and add the claim. */
 
-	backbone_gw = batadv_bla_get_backbone_gw(bat_priv, backbone_addr, vid);
+	backbone_gw = batadv_bla_get_backbone_gw(bat_priv, backbone_addr, vid,
+						 false);
 
 	if (unlikely(!backbone_gw))
 		return 1;
@@ -1140,6 +1159,24 @@ static void batadv_bla_periodic_work(struct work_struct *work)
 			backbone_gw->lasttime = jiffies;
 
 			batadv_bla_send_announce(bat_priv, backbone_gw);
+
+			/* request_sent is only set after creation to avoid
+			 * problems when we are not yet known as backbone gw
+			 * in the backbone.
+			 *
+			 * We can reset this now after we waited some periods
+			 * to give bridge forward delays and bla group forming
+			 * some grace time.
+			 */
+
+			if (atomic_read(&backbone_gw->request_sent) == 0)
+				continue;
+
+			if (!atomic_dec_and_test(&backbone_gw->wait_periods))
+				continue;
+
+			atomic_dec(&backbone_gw->bat_priv->bla.num_requests);
+			atomic_set(&backbone_gw->request_sent, 0);
 		}
 		rcu_read_unlock();
 	}
@@ -1212,8 +1249,7 @@ int batadv_bla_init(struct batadv_priv *bat_priv)
 /**
  * batadv_bla_check_bcast_duplist
  * @bat_priv: the bat priv with all the soft interface information
- * @bcast_packet: encapsulated broadcast frame plus batman header
- * @bcast_packet_len: length of encapsulated broadcast frame plus batman header
+ * @skb: contains the bcast_packet to be checked
  *
  * check if it is on our broadcast list. Another gateway might
  * have sent the same packet because it is connected to the same backbone,
@@ -1225,20 +1261,17 @@ int batadv_bla_init(struct batadv_priv *bat_priv)
  * the same host however as this might be intended.
  */
 int batadv_bla_check_bcast_duplist(struct batadv_priv *bat_priv,
-				   struct batadv_bcast_packet *bcast_packet,
-				   int bcast_packet_len)
+				   struct sk_buff *skb)
 {
-	int i, length, curr, ret = 0;
-	uint8_t *content;
-	uint16_t crc;
+	int i, curr, ret = 0;
+	__be32 crc;
+	struct batadv_bcast_packet *bcast_packet;
 	struct batadv_bcast_duplist_entry *entry;
 
-	length = bcast_packet_len - sizeof(*bcast_packet);
-	content = (uint8_t *)bcast_packet;
-	content += sizeof(*bcast_packet);
+	bcast_packet = (struct batadv_bcast_packet *)skb->data;
 
 	/* calculate the crc ... */
-	crc = crc16(0, content, length);
+	crc = batadv_skb_crc32(skb, (u8 *)(bcast_packet + 1));
 
 	spin_lock_bh(&bat_priv->bla.bcast_duplist_lock);
 
@@ -1585,23 +1618,11 @@ int batadv_bla_claim_table_seq_print_text(struct seq_file *seq, void *offset)
 	struct hlist_head *head;
 	uint32_t i;
 	bool is_own;
-	int ret = 0;
 	uint8_t *primary_addr;
 
-	primary_if = batadv_primary_if_get_selected(bat_priv);
-	if (!primary_if) {
-		ret = seq_printf(seq,
-				 "BATMAN mesh %s disabled - please specify interfaces to enable it\n",
-				 net_dev->name);
-		goto out;
-	}
-
-	if (primary_if->if_status != BATADV_IF_ACTIVE) {
-		ret = seq_printf(seq,
-				 "BATMAN mesh %s disabled - primary interface not active\n",
-				 net_dev->name);
+	primary_if = batadv_seq_print_text_primary_if_get(seq);
+	if (!primary_if)
 		goto out;
-	}
 
 	primary_addr = primary_if->net_dev->dev_addr;
 	seq_printf(seq,
@@ -1628,7 +1649,7 @@ int batadv_bla_claim_table_seq_print_text(struct seq_file *seq, void *offset)
 out:
 	if (primary_if)
 		batadv_hardif_free_ref(primary_if);
-	return ret;
+	return 0;
 }
 
 int batadv_bla_backbone_table_seq_print_text(struct seq_file *seq, void *offset)
@@ -1643,23 +1664,11 @@ int batadv_bla_backbone_table_seq_print_text(struct seq_file *seq, void *offset)
 	int secs, msecs;
 	uint32_t i;
 	bool is_own;
-	int ret = 0;
 	uint8_t *primary_addr;
 
-	primary_if = batadv_primary_if_get_selected(bat_priv);
-	if (!primary_if) {
-		ret = seq_printf(seq,
-				 "BATMAN mesh %s disabled - please specify interfaces to enable it\n",
-				 net_dev->name);
-		goto out;
-	}
-
-	if (primary_if->if_status != BATADV_IF_ACTIVE) {
-		ret = seq_printf(seq,
-				 "BATMAN mesh %s disabled - primary interface not active\n",
-				 net_dev->name);
+	primary_if = batadv_seq_print_text_primary_if_get(seq);
+	if (!primary_if)
 		goto out;
-	}
 
 	primary_addr = primary_if->net_dev->dev_addr;
 	seq_printf(seq,
@@ -1693,5 +1702,5 @@ int batadv_bla_backbone_table_seq_print_text(struct seq_file *seq, void *offset)
 out:
 	if (primary_if)
 		batadv_hardif_free_ref(primary_if);
-	return ret;
+	return 0;
 }
diff --git a/net/batman-adv/bridge_loop_avoidance.h b/net/batman-adv/bridge_loop_avoidance.h
index 789cb73bde67..196d9a0254bc 100644
--- a/net/batman-adv/bridge_loop_avoidance.h
+++ b/net/batman-adv/bridge_loop_avoidance.h
@@ -31,8 +31,7 @@ int batadv_bla_backbone_table_seq_print_text(struct seq_file *seq,
 					     void *offset);
 int batadv_bla_is_backbone_gw_orig(struct batadv_priv *bat_priv, uint8_t *orig);
 int batadv_bla_check_bcast_duplist(struct batadv_priv *bat_priv,
-				   struct batadv_bcast_packet *bcast_packet,
-				   int hdr_size);
+				   struct sk_buff *skb);
 void batadv_bla_update_orig_address(struct batadv_priv *bat_priv,
 				    struct batadv_hard_iface *primary_if,
 				    struct batadv_hard_iface *oldif);
@@ -81,8 +80,7 @@ static inline int batadv_bla_is_backbone_gw_orig(struct batadv_priv *bat_priv,
 
 static inline int
 batadv_bla_check_bcast_duplist(struct batadv_priv *bat_priv,
-			       struct batadv_bcast_packet *bcast_packet,
-			       int hdr_size)
+			       struct sk_buff *skb)
 {
 	return 0;
 }
diff --git a/net/batman-adv/debugfs.c b/net/batman-adv/debugfs.c
index 391d4fb2026f..6f58ddd53bff 100644
--- a/net/batman-adv/debugfs.c
+++ b/net/batman-adv/debugfs.c
@@ -31,6 +31,7 @@
 #include "vis.h"
 #include "icmp_socket.h"
 #include "bridge_loop_avoidance.h"
+#include "distributed-arp-table.h"
 
 static struct dentry *batadv_debugfs;
 
@@ -99,15 +100,17 @@ int batadv_debug_log(struct batadv_priv *bat_priv, const char *fmt, ...)
 
 static int batadv_log_open(struct inode *inode, struct file *file)
 {
+	if (!try_module_get(THIS_MODULE))
+		return -EBUSY;
+
 	nonseekable_open(inode, file);
 	file->private_data = inode->i_private;
-	batadv_inc_module_count();
 	return 0;
 }
 
 static int batadv_log_release(struct inode *inode, struct file *file)
 {
-	batadv_dec_module_count();
+	module_put(THIS_MODULE);
 	return 0;
 }
 
@@ -278,6 +281,19 @@ static int batadv_bla_backbone_table_open(struct inode *inode,
 
 #endif
 
+#ifdef CONFIG_BATMAN_ADV_DAT
+/**
+ * batadv_dat_cache_open - Prepare file handler for reads from dat_chache
+ * @inode: inode which was opened
+ * @file: file handle to be initialized
+ */
+static int batadv_dat_cache_open(struct inode *inode, struct file *file)
+{
+	struct net_device *net_dev = (struct net_device *)inode->i_private;
+	return single_open(file, batadv_dat_cache_seq_print_text, net_dev);
+}
+#endif
+
 static int batadv_transtable_local_open(struct inode *inode, struct file *file)
 {
 	struct net_device *net_dev = (struct net_device *)inode->i_private;
@@ -307,7 +323,17 @@ struct batadv_debuginfo batadv_debuginfo_##_name = {	\
 		}					\
 };
 
+/* the following attributes are general and therefore they will be directly
+ * placed in the BATADV_DEBUGFS_SUBDIR subdirectory of debugfs
+ */
 static BATADV_DEBUGINFO(routing_algos, S_IRUGO, batadv_algorithms_open);
+
+static struct batadv_debuginfo *batadv_general_debuginfos[] = {
+	&batadv_debuginfo_routing_algos,
+	NULL,
+};
+
+/* The following attributes are per soft interface */
 static BATADV_DEBUGINFO(originators, S_IRUGO, batadv_originators_open);
 static BATADV_DEBUGINFO(gateways, S_IRUGO, batadv_gateways_open);
 static BATADV_DEBUGINFO(transtable_global, S_IRUGO,
@@ -317,6 +343,9 @@ static BATADV_DEBUGINFO(bla_claim_table, S_IRUGO, batadv_bla_claim_table_open);
 static BATADV_DEBUGINFO(bla_backbone_table, S_IRUGO,
 			batadv_bla_backbone_table_open);
 #endif
+#ifdef CONFIG_BATMAN_ADV_DAT
+static BATADV_DEBUGINFO(dat_cache, S_IRUGO, batadv_dat_cache_open);
+#endif
 static BATADV_DEBUGINFO(transtable_local, S_IRUGO,
 			batadv_transtable_local_open);
 static BATADV_DEBUGINFO(vis_data, S_IRUGO, batadv_vis_data_open);
@@ -329,6 +358,9 @@ static struct batadv_debuginfo *batadv_mesh_debuginfos[] = {
 	&batadv_debuginfo_bla_claim_table,
 	&batadv_debuginfo_bla_backbone_table,
 #endif
+#ifdef CONFIG_BATMAN_ADV_DAT
+	&batadv_debuginfo_dat_cache,
+#endif
 	&batadv_debuginfo_transtable_local,
 	&batadv_debuginfo_vis_data,
 	NULL,
@@ -336,7 +368,7 @@ static struct batadv_debuginfo *batadv_mesh_debuginfos[] = {
 
 void batadv_debugfs_init(void)
 {
-	struct batadv_debuginfo *bat_debug;
+	struct batadv_debuginfo **bat_debug;
 	struct dentry *file;
 
 	batadv_debugfs = debugfs_create_dir(BATADV_DEBUGFS_SUBDIR, NULL);
@@ -344,17 +376,23 @@ void batadv_debugfs_init(void)
 		batadv_debugfs = NULL;
 
 	if (!batadv_debugfs)
-		goto out;
+		goto err;
 
-	bat_debug = &batadv_debuginfo_routing_algos;
-	file = debugfs_create_file(bat_debug->attr.name,
-				   S_IFREG | bat_debug->attr.mode,
-				   batadv_debugfs, NULL, &bat_debug->fops);
-	if (!file)
-		pr_err("Can't add debugfs file: %s\n", bat_debug->attr.name);
+	for (bat_debug = batadv_general_debuginfos; *bat_debug; ++bat_debug) {
+		file = debugfs_create_file(((*bat_debug)->attr).name,
+					   S_IFREG | ((*bat_debug)->attr).mode,
+					   batadv_debugfs, NULL,
+					   &(*bat_debug)->fops);
+		if (!file) {
+			pr_err("Can't add general debugfs file: %s\n",
+			       ((*bat_debug)->attr).name);
+			goto err;
+		}
+	}
 
-out:
 	return;
+err:
+	debugfs_remove_recursive(batadv_debugfs);
 }
 
 void batadv_debugfs_destroy(void)
diff --git a/net/batman-adv/distributed-arp-table.c b/net/batman-adv/distributed-arp-table.c
new file mode 100644
index 000000000000..8e1d89d2b1c1
--- /dev/null
+++ b/net/batman-adv/distributed-arp-table.c
@@ -0,0 +1,1066 @@
+/* Copyright (C) 2011-2012 B.A.T.M.A.N. contributors:
+ *
+ * Antonio Quartulli
+ *
+ * This program is free software; you can redistribute it and/or
+ * modify it under the terms of version 2 of the GNU General Public
+ * License as published by the Free Software Foundation.
+ *
+ * This program is distributed in the hope that it will be useful, but
+ * WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
+ * General Public License for more details.
+ *
+ * You should have received a copy of the GNU General Public License
+ * along with this program; if not, write to the Free Software
+ * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA
+ * 02110-1301, USA
+ */
+
+#include <linux/if_ether.h>
+#include <linux/if_arp.h>
+#include <net/arp.h>
+
+#include "main.h"
+#include "hash.h"
+#include "distributed-arp-table.h"
+#include "hard-interface.h"
+#include "originator.h"
+#include "send.h"
+#include "types.h"
+#include "translation-table.h"
+#include "unicast.h"
+
+static void batadv_dat_purge(struct work_struct *work);
+
+/**
+ * batadv_dat_start_timer - initialise the DAT periodic worker
+ * @bat_priv: the bat priv with all the soft interface information
+ */
+static void batadv_dat_start_timer(struct batadv_priv *bat_priv)
+{
+	INIT_DELAYED_WORK(&bat_priv->dat.work, batadv_dat_purge);
+	queue_delayed_work(batadv_event_workqueue, &bat_priv->dat.work,
+			   msecs_to_jiffies(10000));
+}
+
+/**
+ * batadv_dat_entry_free_ref - decrements the dat_entry refcounter and possibly
+ * free it
+ * @dat_entry: the oentry to free
+ */
+static void batadv_dat_entry_free_ref(struct batadv_dat_entry *dat_entry)
+{
+	if (atomic_dec_and_test(&dat_entry->refcount))
+		kfree_rcu(dat_entry, rcu);
+}
+
+/**
+ * batadv_dat_to_purge - checks whether a dat_entry has to be purged or not
+ * @dat_entry: the entry to check
+ *
+ * Returns true if the entry has to be purged now, false otherwise
+ */
+static bool batadv_dat_to_purge(struct batadv_dat_entry *dat_entry)
+{
+	return batadv_has_timed_out(dat_entry->last_update,
+				    BATADV_DAT_ENTRY_TIMEOUT);
+}
+
+/**
+ * __batadv_dat_purge - delete entries from the DAT local storage
+ * @bat_priv: the bat priv with all the soft interface information
+ * @to_purge: function in charge to decide whether an entry has to be purged or
+ *	      not. This function takes the dat_entry as argument and has to
+ *	      returns a boolean value: true is the entry has to be deleted,
+ *	      false otherwise
+ *
+ * Loops over each entry in the DAT local storage and delete it if and only if
+ * the to_purge function passed as argument returns true
+ */
+static void __batadv_dat_purge(struct batadv_priv *bat_priv,
+			       bool (*to_purge)(struct batadv_dat_entry *))
+{
+	spinlock_t *list_lock; /* protects write access to the hash lists */
+	struct batadv_dat_entry *dat_entry;
+	struct hlist_node *node, *node_tmp;
+	struct hlist_head *head;
+	uint32_t i;
+
+	if (!bat_priv->dat.hash)
+		return;
+
+	for (i = 0; i < bat_priv->dat.hash->size; i++) {
+		head = &bat_priv->dat.hash->table[i];
+		list_lock = &bat_priv->dat.hash->list_locks[i];
+
+		spin_lock_bh(list_lock);
+		hlist_for_each_entry_safe(dat_entry, node, node_tmp, head,
+					  hash_entry) {
+			/* if an helper function has been passed as parameter,
+			 * ask it if the entry has to be purged or not
+			 */
+			if (to_purge && !to_purge(dat_entry))
+				continue;
+
+			hlist_del_rcu(node);
+			batadv_dat_entry_free_ref(dat_entry);
+		}
+		spin_unlock_bh(list_lock);
+	}
+}
+
+/**
+ * batadv_dat_purge - periodic task that deletes old entries from the local DAT
+ * hash table
+ * @work: kernel work struct
+ */
+static void batadv_dat_purge(struct work_struct *work)
+{
+	struct delayed_work *delayed_work;
+	struct batadv_priv_dat *priv_dat;
+	struct batadv_priv *bat_priv;
+
+	delayed_work = container_of(work, struct delayed_work, work);
+	priv_dat = container_of(delayed_work, struct batadv_priv_dat, work);
+	bat_priv = container_of(priv_dat, struct batadv_priv, dat);
+
+	__batadv_dat_purge(bat_priv, batadv_dat_to_purge);
+	batadv_dat_start_timer(bat_priv);
+}
+
+/**
+ * batadv_compare_dat - comparing function used in the local DAT hash table
+ * @node: node in the local table
+ * @data2: second object to compare the node to
+ *
+ * Returns 1 if the two entry are the same, 0 otherwise
+ */
+static int batadv_compare_dat(const struct hlist_node *node, const void *data2)
+{
+	const void *data1 = container_of(node, struct batadv_dat_entry,
+					 hash_entry);
+
+	return (memcmp(data1, data2, sizeof(__be32)) == 0 ? 1 : 0);
+}
+
+/**
+ * batadv_arp_hw_src - extract the hw_src field from an ARP packet
+ * @skb: ARP packet
+ * @hdr_size: size of the possible header before the ARP packet
+ *
+ * Returns the value of the hw_src field in the ARP packet
+ */
+static uint8_t *batadv_arp_hw_src(struct sk_buff *skb, int hdr_size)
+{
+	uint8_t *addr;
+
+	addr = (uint8_t *)(skb->data + hdr_size);
+	addr += ETH_HLEN + sizeof(struct arphdr);
+
+	return addr;
+}
+
+/**
+ * batadv_arp_ip_src - extract the ip_src field from an ARP packet
+ * @skb: ARP packet
+ * @hdr_size: size of the possible header before the ARP packet
+ *
+ * Returns the value of the ip_src field in the ARP packet
+ */
+static __be32 batadv_arp_ip_src(struct sk_buff *skb, int hdr_size)
+{
+	return *(__be32 *)(batadv_arp_hw_src(skb, hdr_size) + ETH_ALEN);
+}
+
+/**
+ * batadv_arp_hw_dst - extract the hw_dst field from an ARP packet
+ * @skb: ARP packet
+ * @hdr_size: size of the possible header before the ARP packet
+ *
+ * Returns the value of the hw_dst field in the ARP packet
+ */
+static uint8_t *batadv_arp_hw_dst(struct sk_buff *skb, int hdr_size)
+{
+	return batadv_arp_hw_src(skb, hdr_size) + ETH_ALEN + 4;
+}
+
+/**
+ * batadv_arp_ip_dst - extract the ip_dst field from an ARP packet
+ * @skb: ARP packet
+ * @hdr_size: size of the possible header before the ARP packet
+ *
+ * Returns the value of the ip_dst field in the ARP packet
+ */
+static __be32 batadv_arp_ip_dst(struct sk_buff *skb, int hdr_size)
+{
+	return *(__be32 *)(batadv_arp_hw_src(skb, hdr_size) + ETH_ALEN * 2 + 4);
+}
+
+/**
+ * batadv_hash_dat - compute the hash value for an IP address
+ * @data: data to hash
+ * @size: size of the hash table
+ *
+ * Returns the selected index in the hash table for the given data
+ */
+static uint32_t batadv_hash_dat(const void *data, uint32_t size)
+{
+	const unsigned char *key = data;
+	uint32_t hash = 0;
+	size_t i;
+
+	for (i = 0; i < 4; i++) {
+		hash += key[i];
+		hash += (hash << 10);
+		hash ^= (hash >> 6);
+	}
+
+	hash += (hash << 3);
+	hash ^= (hash >> 11);
+	hash += (hash << 15);
+
+	return hash % size;
+}
+
+/**
+ * batadv_dat_entry_hash_find - looks for a given dat_entry in the local hash
+ * table
+ * @bat_priv: the bat priv with all the soft interface information
+ * @ip: search key
+ *
+ * Returns the dat_entry if found, NULL otherwise
+ */
+static struct batadv_dat_entry *
+batadv_dat_entry_hash_find(struct batadv_priv *bat_priv, __be32 ip)
+{
+	struct hlist_head *head;
+	struct hlist_node *node;
+	struct batadv_dat_entry *dat_entry, *dat_entry_tmp = NULL;
+	struct batadv_hashtable *hash = bat_priv->dat.hash;
+	uint32_t index;
+
+	if (!hash)
+		return NULL;
+
+	index = batadv_hash_dat(&ip, hash->size);
+	head = &hash->table[index];
+
+	rcu_read_lock();
+	hlist_for_each_entry_rcu(dat_entry, node, head, hash_entry) {
+		if (dat_entry->ip != ip)
+			continue;
+
+		if (!atomic_inc_not_zero(&dat_entry->refcount))
+			continue;
+
+		dat_entry_tmp = dat_entry;
+		break;
+	}
+	rcu_read_unlock();
+
+	return dat_entry_tmp;
+}
+
+/**
+ * batadv_dat_entry_add - add a new dat entry or update it if already exists
+ * @bat_priv: the bat priv with all the soft interface information
+ * @ip: ipv4 to add/edit
+ * @mac_addr: mac address to assign to the given ipv4
+ */
+static void batadv_dat_entry_add(struct batadv_priv *bat_priv, __be32 ip,
+				 uint8_t *mac_addr)
+{
+	struct batadv_dat_entry *dat_entry;
+	int hash_added;
+
+	dat_entry = batadv_dat_entry_hash_find(bat_priv, ip);
+	/* if this entry is already known, just update it */
+	if (dat_entry) {
+		if (!batadv_compare_eth(dat_entry->mac_addr, mac_addr))
+			memcpy(dat_entry->mac_addr, mac_addr, ETH_ALEN);
+		dat_entry->last_update = jiffies;
+		batadv_dbg(BATADV_DBG_DAT, bat_priv,
+			   "Entry updated: %pI4 %pM\n", &dat_entry->ip,
+			   dat_entry->mac_addr);
+		goto out;
+	}
+
+	dat_entry = kmalloc(sizeof(*dat_entry), GFP_ATOMIC);
+	if (!dat_entry)
+		goto out;
+
+	dat_entry->ip = ip;
+	memcpy(dat_entry->mac_addr, mac_addr, ETH_ALEN);
+	dat_entry->last_update = jiffies;
+	atomic_set(&dat_entry->refcount, 2);
+
+	hash_added = batadv_hash_add(bat_priv->dat.hash, batadv_compare_dat,
+				     batadv_hash_dat, &dat_entry->ip,
+				     &dat_entry->hash_entry);
+
+	if (unlikely(hash_added != 0)) {
+		/* remove the reference for the hash */
+		batadv_dat_entry_free_ref(dat_entry);
+		goto out;
+	}
+
+	batadv_dbg(BATADV_DBG_DAT, bat_priv, "New entry added: %pI4 %pM\n",
+		   &dat_entry->ip, dat_entry->mac_addr);
+
+out:
+	if (dat_entry)
+		batadv_dat_entry_free_ref(dat_entry);
+}
+
+#ifdef CONFIG_BATMAN_ADV_DEBUG
+
+/**
+ * batadv_dbg_arp - print a debug message containing all the ARP packet details
+ * @bat_priv: the bat priv with all the soft interface information
+ * @skb: ARP packet
+ * @type: ARP type
+ * @hdr_size: size of the possible header before the ARP packet
+ * @msg: message to print together with the debugging information
+ */
+static void batadv_dbg_arp(struct batadv_priv *bat_priv, struct sk_buff *skb,
+			   uint16_t type, int hdr_size, char *msg)
+{
+	struct batadv_unicast_4addr_packet *unicast_4addr_packet;
+	struct batadv_bcast_packet *bcast_pkt;
+	uint8_t *orig_addr;
+	__be32 ip_src, ip_dst;
+
+	if (msg)
+		batadv_dbg(BATADV_DBG_DAT, bat_priv, "%s\n", msg);
+
+	ip_src = batadv_arp_ip_src(skb, hdr_size);
+	ip_dst = batadv_arp_ip_dst(skb, hdr_size);
+	batadv_dbg(BATADV_DBG_DAT, bat_priv,
+		   "ARP MSG = [src: %pM-%pI4 dst: %pM-%pI4]\n",
+		   batadv_arp_hw_src(skb, hdr_size), &ip_src,
+		   batadv_arp_hw_dst(skb, hdr_size), &ip_dst);
+
+	if (hdr_size == 0)
+		return;
+
+	/* if the ARP packet is encapsulated in a batman packet, let's print
+	 * some debug messages
+	 */
+	unicast_4addr_packet = (struct batadv_unicast_4addr_packet *)skb->data;
+
+	switch (unicast_4addr_packet->u.header.packet_type) {
+	case BATADV_UNICAST:
+		batadv_dbg(BATADV_DBG_DAT, bat_priv,
+			   "* encapsulated within a UNICAST packet\n");
+		break;
+	case BATADV_UNICAST_4ADDR:
+		batadv_dbg(BATADV_DBG_DAT, bat_priv,
+			   "* encapsulated within a UNICAST_4ADDR packet (src: %pM)\n",
+			   unicast_4addr_packet->src);
+		switch (unicast_4addr_packet->subtype) {
+		case BATADV_P_DAT_DHT_PUT:
+			batadv_dbg(BATADV_DBG_DAT, bat_priv, "* type: DAT_DHT_PUT\n");
+			break;
+		case BATADV_P_DAT_DHT_GET:
+			batadv_dbg(BATADV_DBG_DAT, bat_priv, "* type: DAT_DHT_GET\n");
+			break;
+		case BATADV_P_DAT_CACHE_REPLY:
+			batadv_dbg(BATADV_DBG_DAT, bat_priv,
+				   "* type: DAT_CACHE_REPLY\n");
+			break;
+		case BATADV_P_DATA:
+			batadv_dbg(BATADV_DBG_DAT, bat_priv, "* type: DATA\n");
+			break;
+		default:
+			batadv_dbg(BATADV_DBG_DAT, bat_priv, "* type: Unknown (%u)!\n",
+				   unicast_4addr_packet->u.header.packet_type);
+		}
+		break;
+	case BATADV_BCAST:
+		bcast_pkt = (struct batadv_bcast_packet *)unicast_4addr_packet;
+		orig_addr = bcast_pkt->orig;
+		batadv_dbg(BATADV_DBG_DAT, bat_priv,
+			   "* encapsulated within a BCAST packet (src: %pM)\n",
+			   orig_addr);
+		break;
+	default:
+		batadv_dbg(BATADV_DBG_DAT, bat_priv,
+			   "* encapsulated within an unknown packet type (0x%x)\n",
+			   unicast_4addr_packet->u.header.packet_type);
+	}
+}
+
+#else
+
+static void batadv_dbg_arp(struct batadv_priv *bat_priv, struct sk_buff *skb,
+			   uint16_t type, int hdr_size, char *msg)
+{
+}
+
+#endif /* CONFIG_BATMAN_ADV_DEBUG */
+
+/**
+ * batadv_is_orig_node_eligible - check whether a node can be a DHT candidate
+ * @res: the array with the already selected candidates
+ * @select: number of already selected candidates
+ * @tmp_max: address of the currently evaluated node
+ * @max: current round max address
+ * @last_max: address of the last selected candidate
+ * @candidate: orig_node under evaluation
+ * @max_orig_node: last selected candidate
+ *
+ * Returns true if the node has been elected as next candidate or false othrwise
+ */
+static bool batadv_is_orig_node_eligible(struct batadv_dat_candidate *res,
+					 int select, batadv_dat_addr_t tmp_max,
+					 batadv_dat_addr_t max,
+					 batadv_dat_addr_t last_max,
+					 struct batadv_orig_node *candidate,
+					 struct batadv_orig_node *max_orig_node)
+{
+	bool ret = false;
+	int j;
+
+	/* Check if this node has already been selected... */
+	for (j = 0; j < select; j++)
+		if (res[j].orig_node == candidate)
+			break;
+	/* ..and possibly skip it */
+	if (j < select)
+		goto out;
+	/* sanity check: has it already been selected? This should not happen */
+	if (tmp_max > last_max)
+		goto out;
+	/* check if during this iteration an originator with a closer dht
+	 * address has already been found
+	 */
+	if (tmp_max < max)
+		goto out;
+	/* this is an hash collision with the temporary selected node. Choose
+	 * the one with the lowest address
+	 */
+	if ((tmp_max == max) &&
+	    (batadv_compare_eth(candidate->orig, max_orig_node->orig) > 0))
+		goto out;
+
+	ret = true;
+out:
+	return ret;
+}
+
+/**
+ * batadv_choose_next_candidate - select the next DHT candidate
+ * @bat_priv: the bat priv with all the soft interface information
+ * @cands: candidates array
+ * @select: number of candidates already present in the array
+ * @ip_key: key to look up in the DHT
+ * @last_max: pointer where the address of the selected candidate will be saved
+ */
+static void batadv_choose_next_candidate(struct batadv_priv *bat_priv,
+					 struct batadv_dat_candidate *cands,
+					 int select, batadv_dat_addr_t ip_key,
+					 batadv_dat_addr_t *last_max)
+{
+	batadv_dat_addr_t max = 0, tmp_max = 0;
+	struct batadv_orig_node *orig_node, *max_orig_node = NULL;
+	struct batadv_hashtable *hash = bat_priv->orig_hash;
+	struct hlist_node *node;
+	struct hlist_head *head;
+	int i;
+
+	/* if no node is eligible as candidate, leave the candidate type as
+	 * NOT_FOUND
+	 */
+	cands[select].type = BATADV_DAT_CANDIDATE_NOT_FOUND;
+
+	/* iterate over the originator list and find the node with closest
+	 * dat_address which has not been selected yet
+	 */
+	for (i = 0; i < hash->size; i++) {
+		head = &hash->table[i];
+
+		rcu_read_lock();
+		hlist_for_each_entry_rcu(orig_node, node, head, hash_entry) {
+			/* the dht space is a ring and addresses are unsigned */
+			tmp_max = BATADV_DAT_ADDR_MAX - orig_node->dat_addr +
+				  ip_key;
+
+			if (!batadv_is_orig_node_eligible(cands, select,
+							  tmp_max, max,
+							  *last_max, orig_node,
+							  max_orig_node))
+				continue;
+
+			if (!atomic_inc_not_zero(&orig_node->refcount))
+				continue;
+
+			max = tmp_max;
+			if (max_orig_node)
+				batadv_orig_node_free_ref(max_orig_node);
+			max_orig_node = orig_node;
+		}
+		rcu_read_unlock();
+	}
+	if (max_orig_node) {
+		cands[select].type = BATADV_DAT_CANDIDATE_ORIG;
+		cands[select].orig_node = max_orig_node;
+		batadv_dbg(BATADV_DBG_DAT, bat_priv,
+			   "dat_select_candidates() %d: selected %pM addr=%u dist=%u\n",
+			   select, max_orig_node->orig, max_orig_node->dat_addr,
+			   max);
+	}
+	*last_max = max;
+}
+
+/**
+ * batadv_dat_select_candidates - selects the nodes which the DHT message has to
+ * be sent to
+ * @bat_priv: the bat priv with all the soft interface information
+ * @ip_dst: ipv4 to look up in the DHT
+ *
+ * An originator O is selected if and only if its DHT_ID value is one of three
+ * closest values (from the LEFT, with wrap around if needed) then the hash
+ * value of the key. ip_dst is the key.
+ *
+ * Returns the candidate array of size BATADV_DAT_CANDIDATE_NUM
+ */
+static struct batadv_dat_candidate *
+batadv_dat_select_candidates(struct batadv_priv *bat_priv, __be32 ip_dst)
+{
+	int select;
+	batadv_dat_addr_t last_max = BATADV_DAT_ADDR_MAX, ip_key;
+	struct batadv_dat_candidate *res;
+
+	if (!bat_priv->orig_hash)
+		return NULL;
+
+	res = kmalloc(BATADV_DAT_CANDIDATES_NUM * sizeof(*res), GFP_ATOMIC);
+	if (!res)
+		return NULL;
+
+	ip_key = (batadv_dat_addr_t)batadv_hash_dat(&ip_dst,
+						    BATADV_DAT_ADDR_MAX);
+
+	batadv_dbg(BATADV_DBG_DAT, bat_priv,
+		   "dat_select_candidates(): IP=%pI4 hash(IP)=%u\n", &ip_dst,
+		   ip_key);
+
+	for (select = 0; select < BATADV_DAT_CANDIDATES_NUM; select++)
+		batadv_choose_next_candidate(bat_priv, res, select, ip_key,
+					     &last_max);
+
+	return res;
+}
+
+/**
+ * batadv_dat_send_data - send a payload to the selected candidates
+ * @bat_priv: the bat priv with all the soft interface information
+ * @skb: payload to send
+ * @ip: the DHT key
+ * @packet_subtype: unicast4addr packet subtype to use
+ *
+ * In this function the skb is copied by means of pskb_copy() and is sent as
+ * unicast packet to each of the selected candidates
+ *
+ * Returns true if the packet is sent to at least one candidate, false otherwise
+ */
+static bool batadv_dat_send_data(struct batadv_priv *bat_priv,
+				 struct sk_buff *skb, __be32 ip,
+				 int packet_subtype)
+{
+	int i;
+	bool ret = false;
+	int send_status;
+	struct batadv_neigh_node *neigh_node = NULL;
+	struct sk_buff *tmp_skb;
+	struct batadv_dat_candidate *cand;
+
+	cand = batadv_dat_select_candidates(bat_priv, ip);
+	if (!cand)
+		goto out;
+
+	batadv_dbg(BATADV_DBG_DAT, bat_priv, "DHT_SEND for %pI4\n", &ip);
+
+	for (i = 0; i < BATADV_DAT_CANDIDATES_NUM; i++) {
+		if (cand[i].type == BATADV_DAT_CANDIDATE_NOT_FOUND)
+			continue;
+
+		neigh_node = batadv_orig_node_get_router(cand[i].orig_node);
+		if (!neigh_node)
+			goto free_orig;
+
+		tmp_skb = pskb_copy(skb, GFP_ATOMIC);
+		if (!batadv_unicast_4addr_prepare_skb(bat_priv, tmp_skb,
+						      cand[i].orig_node,
+						      packet_subtype)) {
+			kfree_skb(tmp_skb);
+			goto free_neigh;
+		}
+
+		send_status = batadv_send_skb_packet(tmp_skb,
+						     neigh_node->if_incoming,
+						     neigh_node->addr);
+		if (send_status == NET_XMIT_SUCCESS) {
+			/* count the sent packet */
+			switch (packet_subtype) {
+			case BATADV_P_DAT_DHT_GET:
+				batadv_inc_counter(bat_priv,
+						   BATADV_CNT_DAT_GET_TX);
+				break;
+			case BATADV_P_DAT_DHT_PUT:
+				batadv_inc_counter(bat_priv,
+						   BATADV_CNT_DAT_PUT_TX);
+				break;
+			}
+
+			/* packet sent to a candidate: return true */
+			ret = true;
+		}
+free_neigh:
+		batadv_neigh_node_free_ref(neigh_node);
+free_orig:
+		batadv_orig_node_free_ref(cand[i].orig_node);
+	}
+
+out:
+	kfree(cand);
+	return ret;
+}
+
+/**
+ * batadv_dat_hash_free - free the local DAT hash table
+ * @bat_priv: the bat priv with all the soft interface information
+ */
+static void batadv_dat_hash_free(struct batadv_priv *bat_priv)
+{
+	if (!bat_priv->dat.hash)
+		return;
+
+	__batadv_dat_purge(bat_priv, NULL);
+
+	batadv_hash_destroy(bat_priv->dat.hash);
+
+	bat_priv->dat.hash = NULL;
+}
+
+/**
+ * batadv_dat_init - initialise the DAT internals
+ * @bat_priv: the bat priv with all the soft interface information
+ */
+int batadv_dat_init(struct batadv_priv *bat_priv)
+{
+	if (bat_priv->dat.hash)
+		return 0;
+
+	bat_priv->dat.hash = batadv_hash_new(1024);
+
+	if (!bat_priv->dat.hash)
+		return -ENOMEM;
+
+	batadv_dat_start_timer(bat_priv);
+
+	return 0;
+}
+
+/**
+ * batadv_dat_free - free the DAT internals
+ * @bat_priv: the bat priv with all the soft interface information
+ */
+void batadv_dat_free(struct batadv_priv *bat_priv)
+{
+	cancel_delayed_work_sync(&bat_priv->dat.work);
+
+	batadv_dat_hash_free(bat_priv);
+}
+
+/**
+ * batadv_dat_cache_seq_print_text - print the local DAT hash table
+ * @seq: seq file to print on
+ * @offset: not used
+ */
+int batadv_dat_cache_seq_print_text(struct seq_file *seq, void *offset)
+{
+	struct net_device *net_dev = (struct net_device *)seq->private;
+	struct batadv_priv *bat_priv = netdev_priv(net_dev);
+	struct batadv_hashtable *hash = bat_priv->dat.hash;
+	struct batadv_dat_entry *dat_entry;
+	struct batadv_hard_iface *primary_if;
+	struct hlist_node *node;
+	struct hlist_head *head;
+	unsigned long last_seen_jiffies;
+	int last_seen_msecs, last_seen_secs, last_seen_mins;
+	uint32_t i;
+
+	primary_if = batadv_seq_print_text_primary_if_get(seq);
+	if (!primary_if)
+		goto out;
+
+	seq_printf(seq, "Distributed ARP Table (%s):\n", net_dev->name);
+	seq_printf(seq, "          %-7s          %-13s %5s\n", "IPv4", "MAC",
+		   "last-seen");
+
+	for (i = 0; i < hash->size; i++) {
+		head = &hash->table[i];
+
+		rcu_read_lock();
+		hlist_for_each_entry_rcu(dat_entry, node, head, hash_entry) {
+			last_seen_jiffies = jiffies - dat_entry->last_update;
+			last_seen_msecs = jiffies_to_msecs(last_seen_jiffies);
+			last_seen_mins = last_seen_msecs / 60000;
+			last_seen_msecs = last_seen_msecs % 60000;
+			last_seen_secs = last_seen_msecs / 1000;
+
+			seq_printf(seq, " * %15pI4 %14pM %6i:%02i\n",
+				   &dat_entry->ip, dat_entry->mac_addr,
+				   last_seen_mins, last_seen_secs);
+		}
+		rcu_read_unlock();
+	}
+
+out:
+	if (primary_if)
+		batadv_hardif_free_ref(primary_if);
+	return 0;
+}
+
+/**
+ * batadv_arp_get_type - parse an ARP packet and gets the type
+ * @bat_priv: the bat priv with all the soft interface information
+ * @skb: packet to analyse
+ * @hdr_size: size of the possible header before the ARP packet in the skb
+ *
+ * Returns the ARP type if the skb contains a valid ARP packet, 0 otherwise
+ */
+static uint16_t batadv_arp_get_type(struct batadv_priv *bat_priv,
+				    struct sk_buff *skb, int hdr_size)
+{
+	struct arphdr *arphdr;
+	struct ethhdr *ethhdr;
+	__be32 ip_src, ip_dst;
+	uint16_t type = 0;
+
+	/* pull the ethernet header */
+	if (unlikely(!pskb_may_pull(skb, hdr_size + ETH_HLEN)))
+		goto out;
+
+	ethhdr = (struct ethhdr *)(skb->data + hdr_size);
+
+	if (ethhdr->h_proto != htons(ETH_P_ARP))
+		goto out;
+
+	/* pull the ARP payload */
+	if (unlikely(!pskb_may_pull(skb, hdr_size + ETH_HLEN +
+				    arp_hdr_len(skb->dev))))
+		goto out;
+
+	arphdr = (struct arphdr *)(skb->data + hdr_size + ETH_HLEN);
+
+	/* Check whether the ARP packet carries a valid
+	 * IP information
+	 */
+	if (arphdr->ar_hrd != htons(ARPHRD_ETHER))
+		goto out;
+
+	if (arphdr->ar_pro != htons(ETH_P_IP))
+		goto out;
+
+	if (arphdr->ar_hln != ETH_ALEN)
+		goto out;
+
+	if (arphdr->ar_pln != 4)
+		goto out;
+
+	/* Check for bad reply/request. If the ARP message is not sane, DAT
+	 * will simply ignore it
+	 */
+	ip_src = batadv_arp_ip_src(skb, hdr_size);
+	ip_dst = batadv_arp_ip_dst(skb, hdr_size);
+	if (ipv4_is_loopback(ip_src) || ipv4_is_multicast(ip_src) ||
+	    ipv4_is_loopback(ip_dst) || ipv4_is_multicast(ip_dst))
+		goto out;
+
+	type = ntohs(arphdr->ar_op);
+out:
+	return type;
+}
+
+/**
+ * batadv_dat_snoop_outgoing_arp_request - snoop the ARP request and try to
+ * answer using DAT
+ * @bat_priv: the bat priv with all the soft interface information
+ * @skb: packet to check
+ *
+ * Returns true if the message has been sent to the dht candidates, false
+ * otherwise. In case of true the message has to be enqueued to permit the
+ * fallback
+ */
+bool batadv_dat_snoop_outgoing_arp_request(struct batadv_priv *bat_priv,
+					   struct sk_buff *skb)
+{
+	uint16_t type = 0;
+	__be32 ip_dst, ip_src;
+	uint8_t *hw_src;
+	bool ret = false;
+	struct batadv_dat_entry *dat_entry = NULL;
+	struct sk_buff *skb_new;
+	struct batadv_hard_iface *primary_if = NULL;
+
+	if (!atomic_read(&bat_priv->distributed_arp_table))
+		goto out;
+
+	type = batadv_arp_get_type(bat_priv, skb, 0);
+	/* If the node gets an ARP_REQUEST it has to send a DHT_GET unicast
+	 * message to the selected DHT candidates
+	 */
+	if (type != ARPOP_REQUEST)
+		goto out;
+
+	batadv_dbg_arp(bat_priv, skb, type, 0, "Parsing outgoing ARP REQUEST");
+
+	ip_src = batadv_arp_ip_src(skb, 0);
+	hw_src = batadv_arp_hw_src(skb, 0);
+	ip_dst = batadv_arp_ip_dst(skb, 0);
+
+	batadv_dat_entry_add(bat_priv, ip_src, hw_src);
+
+	dat_entry = batadv_dat_entry_hash_find(bat_priv, ip_dst);
+	if (dat_entry) {
+		primary_if = batadv_primary_if_get_selected(bat_priv);
+		if (!primary_if)
+			goto out;
+
+		skb_new = arp_create(ARPOP_REPLY, ETH_P_ARP, ip_src,
+				     primary_if->soft_iface, ip_dst, hw_src,
+				     dat_entry->mac_addr, hw_src);
+		if (!skb_new)
+			goto out;
+
+		skb_reset_mac_header(skb_new);
+		skb_new->protocol = eth_type_trans(skb_new,
+						   primary_if->soft_iface);
+		bat_priv->stats.rx_packets++;
+		bat_priv->stats.rx_bytes += skb->len + ETH_HLEN;
+		primary_if->soft_iface->last_rx = jiffies;
+
+		netif_rx(skb_new);
+		batadv_dbg(BATADV_DBG_DAT, bat_priv, "ARP request replied locally\n");
+		ret = true;
+	} else {
+		/* Send the request on the DHT */
+		ret = batadv_dat_send_data(bat_priv, skb, ip_dst,
+					   BATADV_P_DAT_DHT_GET);
+	}
+out:
+	if (dat_entry)
+		batadv_dat_entry_free_ref(dat_entry);
+	if (primary_if)
+		batadv_hardif_free_ref(primary_if);
+	return ret;
+}
+
+/**
+ * batadv_dat_snoop_incoming_arp_request - snoop the ARP request and try to
+ * answer using the local DAT storage
+ * @bat_priv: the bat priv with all the soft interface information
+ * @skb: packet to check
+ * @hdr_size: size of the encapsulation header
+ *
+ * Returns true if the request has been answered, false otherwise
+ */
+bool batadv_dat_snoop_incoming_arp_request(struct batadv_priv *bat_priv,
+					   struct sk_buff *skb, int hdr_size)
+{
+	uint16_t type;
+	__be32 ip_src, ip_dst;
+	uint8_t *hw_src;
+	struct sk_buff *skb_new;
+	struct batadv_hard_iface *primary_if = NULL;
+	struct batadv_dat_entry *dat_entry = NULL;
+	bool ret = false;
+	int err;
+
+	if (!atomic_read(&bat_priv->distributed_arp_table))
+		goto out;
+
+	type = batadv_arp_get_type(bat_priv, skb, hdr_size);
+	if (type != ARPOP_REQUEST)
+		goto out;
+
+	hw_src = batadv_arp_hw_src(skb, hdr_size);
+	ip_src = batadv_arp_ip_src(skb, hdr_size);
+	ip_dst = batadv_arp_ip_dst(skb, hdr_size);
+
+	batadv_dbg_arp(bat_priv, skb, type, hdr_size,
+		       "Parsing incoming ARP REQUEST");
+
+	batadv_dat_entry_add(bat_priv, ip_src, hw_src);
+
+	dat_entry = batadv_dat_entry_hash_find(bat_priv, ip_dst);
+	if (!dat_entry)
+		goto out;
+
+	primary_if = batadv_primary_if_get_selected(bat_priv);
+	if (!primary_if)
+		goto out;
+
+	skb_new = arp_create(ARPOP_REPLY, ETH_P_ARP, ip_src,
+			     primary_if->soft_iface, ip_dst, hw_src,
+			     dat_entry->mac_addr, hw_src);
+
+	if (!skb_new)
+		goto out;
+
+	/* to preserve backwards compatibility, here the node has to answer
+	 * using the same packet type it received for the request. This is due
+	 * to that if a node is not using the 4addr packet format it may not
+	 * support it.
+	 */
+	if (hdr_size == sizeof(struct batadv_unicast_4addr_packet))
+		err = batadv_unicast_4addr_send_skb(bat_priv, skb_new,
+						    BATADV_P_DAT_CACHE_REPLY);
+	else
+		err = batadv_unicast_send_skb(bat_priv, skb_new);
+
+	if (!err) {
+		batadv_inc_counter(bat_priv, BATADV_CNT_DAT_CACHED_REPLY_TX);
+		ret = true;
+	}
+out:
+	if (dat_entry)
+		batadv_dat_entry_free_ref(dat_entry);
+	if (primary_if)
+		batadv_hardif_free_ref(primary_if);
+	if (ret)
+		kfree_skb(skb);
+	return ret;
+}
+
+/**
+ * batadv_dat_snoop_outgoing_arp_reply - snoop the ARP reply and fill the DHT
+ * @bat_priv: the bat priv with all the soft interface information
+ * @skb: packet to check
+ */
+void batadv_dat_snoop_outgoing_arp_reply(struct batadv_priv *bat_priv,
+					 struct sk_buff *skb)
+{
+	uint16_t type;
+	__be32 ip_src, ip_dst;
+	uint8_t *hw_src, *hw_dst;
+
+	if (!atomic_read(&bat_priv->distributed_arp_table))
+		return;
+
+	type = batadv_arp_get_type(bat_priv, skb, 0);
+	if (type != ARPOP_REPLY)
+		return;
+
+	batadv_dbg_arp(bat_priv, skb, type, 0, "Parsing outgoing ARP REPLY");
+
+	hw_src = batadv_arp_hw_src(skb, 0);
+	ip_src = batadv_arp_ip_src(skb, 0);
+	hw_dst = batadv_arp_hw_dst(skb, 0);
+	ip_dst = batadv_arp_ip_dst(skb, 0);
+
+	batadv_dat_entry_add(bat_priv, ip_src, hw_src);
+	batadv_dat_entry_add(bat_priv, ip_dst, hw_dst);
+
+	/* Send the ARP reply to the candidates for both the IP addresses that
+	 * the node got within the ARP reply
+	 */
+	batadv_dat_send_data(bat_priv, skb, ip_src, BATADV_P_DAT_DHT_PUT);
+	batadv_dat_send_data(bat_priv, skb, ip_dst, BATADV_P_DAT_DHT_PUT);
+}
+/**
+ * batadv_dat_snoop_incoming_arp_reply - snoop the ARP reply and fill the local
+ * DAT storage only
+ * @bat_priv: the bat priv with all the soft interface information
+ * @skb: packet to check
+ * @hdr_size: siaze of the encapsulation header
+ */
+bool batadv_dat_snoop_incoming_arp_reply(struct batadv_priv *bat_priv,
+					 struct sk_buff *skb, int hdr_size)
+{
+	uint16_t type;
+	__be32 ip_src, ip_dst;
+	uint8_t *hw_src, *hw_dst;
+	bool ret = false;
+
+	if (!atomic_read(&bat_priv->distributed_arp_table))
+		goto out;
+
+	type = batadv_arp_get_type(bat_priv, skb, hdr_size);
+	if (type != ARPOP_REPLY)
+		goto out;
+
+	batadv_dbg_arp(bat_priv, skb, type, hdr_size,
+		       "Parsing incoming ARP REPLY");
+
+	hw_src = batadv_arp_hw_src(skb, hdr_size);
+	ip_src = batadv_arp_ip_src(skb, hdr_size);
+	hw_dst = batadv_arp_hw_dst(skb, hdr_size);
+	ip_dst = batadv_arp_ip_dst(skb, hdr_size);
+
+	/* Update our internal cache with both the IP addresses the node got
+	 * within the ARP reply
+	 */
+	batadv_dat_entry_add(bat_priv, ip_src, hw_src);
+	batadv_dat_entry_add(bat_priv, ip_dst, hw_dst);
+
+	/* if this REPLY is directed to a client of mine, let's deliver the
+	 * packet to the interface
+	 */
+	ret = !batadv_is_my_client(bat_priv, hw_dst);
+out:
+	/* if ret == false -> packet has to be delivered to the interface */
+	return ret;
+}
+
+/**
+ * batadv_dat_drop_broadcast_packet - check if an ARP request has to be dropped
+ * (because the node has already got the reply via DAT) or not
+ * @bat_priv: the bat priv with all the soft interface information
+ * @forw_packet: the broadcast packet
+ *
+ * Returns true if the node can drop the packet, false otherwise
+ */
+bool batadv_dat_drop_broadcast_packet(struct batadv_priv *bat_priv,
+				      struct batadv_forw_packet *forw_packet)
+{
+	uint16_t type;
+	__be32 ip_dst;
+	struct batadv_dat_entry *dat_entry = NULL;
+	bool ret = false;
+	const size_t bcast_len = sizeof(struct batadv_bcast_packet);
+
+	if (!atomic_read(&bat_priv->distributed_arp_table))
+		goto out;
+
+	/* If this packet is an ARP_REQUEST and the node already has the
+	 * information that it is going to ask, then the packet can be dropped
+	 */
+	if (forw_packet->num_packets)
+		goto out;
+
+	type = batadv_arp_get_type(bat_priv, forw_packet->skb, bcast_len);
+	if (type != ARPOP_REQUEST)
+		goto out;
+
+	ip_dst = batadv_arp_ip_dst(forw_packet->skb, bcast_len);
+	dat_entry = batadv_dat_entry_hash_find(bat_priv, ip_dst);
+	/* check if the node already got this entry */
+	if (!dat_entry) {
+		batadv_dbg(BATADV_DBG_DAT, bat_priv,
+			   "ARP Request for %pI4: fallback\n", &ip_dst);
+		goto out;
+	}
+
+	batadv_dbg(BATADV_DBG_DAT, bat_priv,
+		   "ARP Request for %pI4: fallback prevented\n", &ip_dst);
+	ret = true;
+
+out:
+	if (dat_entry)
+		batadv_dat_entry_free_ref(dat_entry);
+	return ret;
+}
diff --git a/net/batman-adv/distributed-arp-table.h b/net/batman-adv/distributed-arp-table.h
new file mode 100644
index 000000000000..d060c033e7de
--- /dev/null
+++ b/net/batman-adv/distributed-arp-table.h
@@ -0,0 +1,167 @@
+/* Copyright (C) 2011-2012 B.A.T.M.A.N. contributors:
+ *
+ * Antonio Quartulli
+ *
+ * This program is free software; you can redistribute it and/or
+ * modify it under the terms of version 2 of the GNU General Public
+ * License as published by the Free Software Foundation.
+ *
+ * This program is distributed in the hope that it will be useful, but
+ * WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
+ * General Public License for more details.
+ *
+ * You should have received a copy of the GNU General Public License
+ * along with this program; if not, write to the Free Software
+ * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA
+ * 02110-1301, USA
+ */
+
+#ifndef _NET_BATMAN_ADV_ARP_H_
+#define _NET_BATMAN_ADV_ARP_H_
+
+#ifdef CONFIG_BATMAN_ADV_DAT
+
+#include "types.h"
+#include "originator.h"
+
+#include <linux/if_arp.h>
+
+#define BATADV_DAT_ADDR_MAX ((batadv_dat_addr_t)~(batadv_dat_addr_t)0)
+
+bool batadv_dat_snoop_outgoing_arp_request(struct batadv_priv *bat_priv,
+					   struct sk_buff *skb);
+bool batadv_dat_snoop_incoming_arp_request(struct batadv_priv *bat_priv,
+					   struct sk_buff *skb, int hdr_size);
+void batadv_dat_snoop_outgoing_arp_reply(struct batadv_priv *bat_priv,
+					 struct sk_buff *skb);
+bool batadv_dat_snoop_incoming_arp_reply(struct batadv_priv *bat_priv,
+					 struct sk_buff *skb, int hdr_size);
+bool batadv_dat_drop_broadcast_packet(struct batadv_priv *bat_priv,
+				      struct batadv_forw_packet *forw_packet);
+
+/**
+ * batadv_dat_init_orig_node_addr - assign a DAT address to the orig_node
+ * @orig_node: the node to assign the DAT address to
+ */
+static inline void
+batadv_dat_init_orig_node_addr(struct batadv_orig_node *orig_node)
+{
+	uint32_t addr;
+
+	addr = batadv_choose_orig(orig_node->orig, BATADV_DAT_ADDR_MAX);
+	orig_node->dat_addr = (batadv_dat_addr_t)addr;
+}
+
+/**
+ * batadv_dat_init_own_addr - assign a DAT address to the node itself
+ * @bat_priv: the bat priv with all the soft interface information
+ * @primary_if: a pointer to the primary interface
+ */
+static inline void
+batadv_dat_init_own_addr(struct batadv_priv *bat_priv,
+			 struct batadv_hard_iface *primary_if)
+{
+	uint32_t addr;
+
+	addr = batadv_choose_orig(primary_if->net_dev->dev_addr,
+				  BATADV_DAT_ADDR_MAX);
+
+	bat_priv->dat.addr = (batadv_dat_addr_t)addr;
+}
+
+int batadv_dat_init(struct batadv_priv *bat_priv);
+void batadv_dat_free(struct batadv_priv *bat_priv);
+int batadv_dat_cache_seq_print_text(struct seq_file *seq, void *offset);
+
+/**
+ * batadv_dat_inc_counter - increment the correct DAT packet counter
+ * @bat_priv: the bat priv with all the soft interface information
+ * @subtype: the 4addr subtype of the packet to be counted
+ *
+ * Updates the ethtool statistics for the received packet if it is a DAT subtype
+ */
+static inline void batadv_dat_inc_counter(struct batadv_priv *bat_priv,
+					  uint8_t subtype)
+{
+	switch (subtype) {
+	case BATADV_P_DAT_DHT_GET:
+		batadv_inc_counter(bat_priv,
+				   BATADV_CNT_DAT_GET_RX);
+		break;
+	case BATADV_P_DAT_DHT_PUT:
+		batadv_inc_counter(bat_priv,
+				   BATADV_CNT_DAT_PUT_RX);
+		break;
+	}
+}
+
+#else
+
+static inline bool
+batadv_dat_snoop_outgoing_arp_request(struct batadv_priv *bat_priv,
+				      struct sk_buff *skb)
+{
+	return false;
+}
+
+static inline bool
+batadv_dat_snoop_incoming_arp_request(struct batadv_priv *bat_priv,
+				      struct sk_buff *skb, int hdr_size)
+{
+	return false;
+}
+
+static inline bool
+batadv_dat_snoop_outgoing_arp_reply(struct batadv_priv *bat_priv,
+				    struct sk_buff *skb)
+{
+	return false;
+}
+
+static inline bool
+batadv_dat_snoop_incoming_arp_reply(struct batadv_priv *bat_priv,
+				    struct sk_buff *skb, int hdr_size)
+{
+	return false;
+}
+
+static inline bool
+batadv_dat_drop_broadcast_packet(struct batadv_priv *bat_priv,
+				 struct batadv_forw_packet *forw_packet)
+{
+	return false;
+}
+
+static inline void
+batadv_dat_init_orig_node_addr(struct batadv_orig_node *orig_node)
+{
+}
+
+static inline void batadv_dat_init_own_addr(struct batadv_priv *bat_priv,
+					    struct batadv_hard_iface *iface)
+{
+}
+
+static inline void batadv_arp_change_timeout(struct net_device *soft_iface,
+					     const char *name)
+{
+}
+
+static inline int batadv_dat_init(struct batadv_priv *bat_priv)
+{
+	return 0;
+}
+
+static inline void batadv_dat_free(struct batadv_priv *bat_priv)
+{
+}
+
+static inline void batadv_dat_inc_counter(struct batadv_priv *bat_priv,
+					  uint8_t subtype)
+{
+}
+
+#endif /* CONFIG_BATMAN_ADV_DAT */
+
+#endif /* _NET_BATMAN_ADV_ARP_H_ */
diff --git a/net/batman-adv/gateway_client.c b/net/batman-adv/gateway_client.c
index 15d67abc10a4..dd07c7e3654f 100644
--- a/net/batman-adv/gateway_client.c
+++ b/net/batman-adv/gateway_client.c
@@ -477,22 +477,11 @@ int batadv_gw_client_seq_print_text(struct seq_file *seq, void *offset)
 	struct batadv_hard_iface *primary_if;
 	struct batadv_gw_node *gw_node;
 	struct hlist_node *node;
-	int gw_count = 0, ret = 0;
+	int gw_count = 0;
 
-	primary_if = batadv_primary_if_get_selected(bat_priv);
-	if (!primary_if) {
-		ret = seq_printf(seq,
-				 "BATMAN mesh %s disabled - please specify interfaces to enable it\n",
-				 net_dev->name);
+	primary_if = batadv_seq_print_text_primary_if_get(seq);
+	if (!primary_if)
 		goto out;
-	}
-
-	if (primary_if->if_status != BATADV_IF_ACTIVE) {
-		ret = seq_printf(seq,
-				 "BATMAN mesh %s disabled - primary interface not active\n",
-				 net_dev->name);
-		goto out;
-	}
 
 	seq_printf(seq,
 		   "      %-12s (%s/%i) %17s [%10s]: gw_class ... [B.A.T.M.A.N. adv %s, MainIF/MAC: %s/%pM (%s)]\n",
@@ -519,7 +508,7 @@ int batadv_gw_client_seq_print_text(struct seq_file *seq, void *offset)
 out:
 	if (primary_if)
 		batadv_hardif_free_ref(primary_if);
-	return ret;
+	return 0;
 }
 
 static bool batadv_is_type_dhcprequest(struct sk_buff *skb, int header_len)
diff --git a/net/batman-adv/hard-interface.c b/net/batman-adv/hard-interface.c
index d112fd6750b0..f1d37cd81815 100644
--- a/net/batman-adv/hard-interface.c
+++ b/net/batman-adv/hard-interface.c
@@ -18,6 +18,7 @@
  */
 
 #include "main.h"
+#include "distributed-arp-table.h"
 #include "hard-interface.h"
 #include "soft-interface.h"
 #include "send.h"
@@ -29,6 +30,7 @@
 #include "bridge_loop_avoidance.h"
 
 #include <linux/if_arp.h>
+#include <linux/if_ether.h>
 
 void batadv_hardif_free_rcu(struct rcu_head *rcu)
 {
@@ -58,6 +60,45 @@ out:
 	return hard_iface;
 }
 
+/**
+ * batadv_is_on_batman_iface - check if a device is a batman iface descendant
+ * @net_dev: the device to check
+ *
+ * If the user creates any virtual device on top of a batman-adv interface, it
+ * is important to prevent this new interface to be used to create a new mesh
+ * network (this behaviour would lead to a batman-over-batman configuration).
+ * This function recursively checks all the fathers of the device passed as
+ * argument looking for a batman-adv soft interface.
+ *
+ * Returns true if the device is descendant of a batman-adv mesh interface (or
+ * if it is a batman-adv interface itself), false otherwise
+ */
+static bool batadv_is_on_batman_iface(const struct net_device *net_dev)
+{
+	struct net_device *parent_dev;
+	bool ret;
+
+	/* check if this is a batman-adv mesh interface */
+	if (batadv_softif_is_valid(net_dev))
+		return true;
+
+	/* no more parents..stop recursion */
+	if (net_dev->iflink == net_dev->ifindex)
+		return false;
+
+	/* recurse over the parent device */
+	parent_dev = dev_get_by_index(&init_net, net_dev->iflink);
+	/* if we got a NULL parent_dev there is something broken.. */
+	if (WARN(!parent_dev, "Cannot find parent device"))
+		return false;
+
+	ret = batadv_is_on_batman_iface(parent_dev);
+
+	if (parent_dev)
+		dev_put(parent_dev);
+	return ret;
+}
+
 static int batadv_is_valid_iface(const struct net_device *net_dev)
 {
 	if (net_dev->flags & IFF_LOOPBACK)
@@ -70,7 +111,7 @@ static int batadv_is_valid_iface(const struct net_device *net_dev)
 		return 0;
 
 	/* no batman over batman */
-	if (batadv_softif_is_valid(net_dev))
+	if (batadv_is_on_batman_iface(net_dev))
 		return 0;
 
 	return 1;
@@ -109,6 +150,8 @@ static void batadv_primary_if_update_addr(struct batadv_priv *bat_priv,
 	if (!primary_if)
 		goto out;
 
+	batadv_dat_init_own_addr(bat_priv, primary_if);
+
 	skb = bat_priv->vis.my_info->skb_packet;
 	vis_packet = (struct batadv_vis_packet *)skb->data;
 	memcpy(vis_packet->vis_orig, primary_if->net_dev->dev_addr, ETH_ALEN);
@@ -269,7 +312,7 @@ int batadv_hardif_enable_interface(struct batadv_hard_iface *hard_iface,
 {
 	struct batadv_priv *bat_priv;
 	struct net_device *soft_iface;
-	__be16 ethertype = __constant_htons(BATADV_ETH_P_BATMAN);
+	__be16 ethertype = __constant_htons(ETH_P_BATMAN);
 	int ret;
 
 	if (hard_iface->if_status != BATADV_IF_NOT_IN_USE)
@@ -450,8 +493,8 @@ batadv_hardif_add_interface(struct net_device *net_dev)
 	/* This can't be called via a bat_priv callback because
 	 * we have no bat_priv yet.
 	 */
-	atomic_set(&hard_iface->seqno, 1);
-	hard_iface->packet_buff = NULL;
+	atomic_set(&hard_iface->bat_iv.ogm_seqno, 1);
+	hard_iface->bat_iv.ogm_buff = NULL;
 
 	return hard_iface;
 
diff --git a/net/batman-adv/hash.h b/net/batman-adv/hash.h
index 977de9c75fc2..e05333905afd 100644
--- a/net/batman-adv/hash.h
+++ b/net/batman-adv/hash.h
@@ -82,6 +82,28 @@ static inline void batadv_hash_delete(struct batadv_hashtable *hash,
 }
 
 /**
+ *	batadv_hash_bytes - hash some bytes and add them to the previous hash
+ *	@hash: previous hash value
+ *	@data: data to be hashed
+ *	@size: number of bytes to be hashed
+ *
+ *	Returns the new hash value.
+ */
+static inline uint32_t batadv_hash_bytes(uint32_t hash, void *data,
+					 uint32_t size)
+{
+	const unsigned char *key = data;
+	int i;
+
+	for (i = 0; i < size; i++) {
+		hash += key[i];
+		hash += (hash << 10);
+		hash ^= (hash >> 6);
+	}
+	return hash;
+}
+
+/**
  *	batadv_hash_add - adds data to the hashtable
  *	@hash: storage hash table
  *	@compare: callback to determine if 2 hash elements are identical
diff --git a/net/batman-adv/icmp_socket.c b/net/batman-adv/icmp_socket.c
index bde3cf747507..87ca8095b011 100644
--- a/net/batman-adv/icmp_socket.c
+++ b/net/batman-adv/icmp_socket.c
@@ -42,12 +42,16 @@ static int batadv_socket_open(struct inode *inode, struct file *file)
 	unsigned int i;
 	struct batadv_socket_client *socket_client;
 
+	if (!try_module_get(THIS_MODULE))
+		return -EBUSY;
+
 	nonseekable_open(inode, file);
 
 	socket_client = kmalloc(sizeof(*socket_client), GFP_KERNEL);
-
-	if (!socket_client)
+	if (!socket_client) {
+		module_put(THIS_MODULE);
 		return -ENOMEM;
+	}
 
 	for (i = 0; i < ARRAY_SIZE(batadv_socket_client_hash); i++) {
 		if (!batadv_socket_client_hash[i]) {
@@ -59,6 +63,7 @@ static int batadv_socket_open(struct inode *inode, struct file *file)
 	if (i == ARRAY_SIZE(batadv_socket_client_hash)) {
 		pr_err("Error - can't add another packet client: maximum number of clients reached\n");
 		kfree(socket_client);
+		module_put(THIS_MODULE);
 		return -EXFULL;
 	}
 
@@ -71,7 +76,6 @@ static int batadv_socket_open(struct inode *inode, struct file *file)
 
 	file->private_data = socket_client;
 
-	batadv_inc_module_count();
 	return 0;
 }
 
@@ -96,7 +100,7 @@ static int batadv_socket_release(struct inode *inode, struct file *file)
 	spin_unlock_bh(&socket_client->lock);
 
 	kfree(socket_client);
-	batadv_dec_module_count();
+	module_put(THIS_MODULE);
 
 	return 0;
 }
@@ -173,13 +177,13 @@ static ssize_t batadv_socket_write(struct file *file, const char __user *buff,
 	if (len >= sizeof(struct batadv_icmp_packet_rr))
 		packet_len = sizeof(struct batadv_icmp_packet_rr);
 
-	skb = dev_alloc_skb(packet_len + ETH_HLEN);
+	skb = dev_alloc_skb(packet_len + ETH_HLEN + NET_IP_ALIGN);
 	if (!skb) {
 		len = -ENOMEM;
 		goto out;
 	}
 
-	skb_reserve(skb, ETH_HLEN);
+	skb_reserve(skb, ETH_HLEN + NET_IP_ALIGN);
 	icmp_packet = (struct batadv_icmp_packet_rr *)skb_put(skb, packet_len);
 
 	if (copy_from_user(icmp_packet, buff, packet_len)) {
diff --git a/net/batman-adv/main.c b/net/batman-adv/main.c
index b4aa470bc4a6..f65a222b7b83 100644
--- a/net/batman-adv/main.c
+++ b/net/batman-adv/main.c
@@ -17,6 +17,8 @@
  * 02110-1301, USA
  */
 
+#include <linux/crc32c.h>
+#include <linux/highmem.h>
 #include "main.h"
 #include "sysfs.h"
 #include "debugfs.h"
@@ -29,6 +31,7 @@
 #include "hard-interface.h"
 #include "gateway_client.h"
 #include "bridge_loop_avoidance.h"
+#include "distributed-arp-table.h"
 #include "vis.h"
 #include "hash.h"
 #include "bat_algo.h"
@@ -128,6 +131,10 @@ int batadv_mesh_init(struct net_device *soft_iface)
 	if (ret < 0)
 		goto err;
 
+	ret = batadv_dat_init(bat_priv);
+	if (ret < 0)
+		goto err;
+
 	atomic_set(&bat_priv->gw.reselect, 0);
 	atomic_set(&bat_priv->mesh_state, BATADV_MESH_ACTIVE);
 
@@ -155,21 +162,13 @@ void batadv_mesh_free(struct net_device *soft_iface)
 
 	batadv_bla_free(bat_priv);
 
+	batadv_dat_free(bat_priv);
+
 	free_percpu(bat_priv->bat_counters);
 
 	atomic_set(&bat_priv->mesh_state, BATADV_MESH_INACTIVE);
 }
 
-void batadv_inc_module_count(void)
-{
-	try_module_get(THIS_MODULE);
-}
-
-void batadv_dec_module_count(void)
-{
-	module_put(THIS_MODULE);
-}
-
 int batadv_is_my_mac(const uint8_t *addr)
 {
 	const struct batadv_hard_iface *hard_iface;
@@ -188,6 +187,42 @@ int batadv_is_my_mac(const uint8_t *addr)
 	return 0;
 }
 
+/**
+ * batadv_seq_print_text_primary_if_get - called from debugfs table printing
+ *  function that requires the primary interface
+ * @seq: debugfs table seq_file struct
+ *
+ * Returns primary interface if found or NULL otherwise.
+ */
+struct batadv_hard_iface *
+batadv_seq_print_text_primary_if_get(struct seq_file *seq)
+{
+	struct net_device *net_dev = (struct net_device *)seq->private;
+	struct batadv_priv *bat_priv = netdev_priv(net_dev);
+	struct batadv_hard_iface *primary_if;
+
+	primary_if = batadv_primary_if_get_selected(bat_priv);
+
+	if (!primary_if) {
+		seq_printf(seq,
+			   "BATMAN mesh %s disabled - please specify interfaces to enable it\n",
+			   net_dev->name);
+		goto out;
+	}
+
+	if (primary_if->if_status == BATADV_IF_ACTIVE)
+		goto out;
+
+	seq_printf(seq,
+		   "BATMAN mesh %s disabled - primary interface not active\n",
+		   net_dev->name);
+	batadv_hardif_free_ref(primary_if);
+	primary_if = NULL;
+
+out:
+	return primary_if;
+}
+
 static int batadv_recv_unhandled_packet(struct sk_buff *skb,
 					struct batadv_hard_iface *recv_if)
 {
@@ -274,6 +309,8 @@ static void batadv_recv_handler_init(void)
 
 	/* batman icmp packet */
 	batadv_rx_handler[BATADV_ICMP] = batadv_recv_icmp_packet;
+	/* 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 */
@@ -385,6 +422,38 @@ int batadv_algo_seq_print_text(struct seq_file *seq, void *offset)
 	return 0;
 }
 
+/**
+ * batadv_skb_crc32 - calculate CRC32 of the whole packet and skip bytes in
+ *  the header
+ * @skb: skb pointing to fragmented socket buffers
+ * @payload_ptr: Pointer to position inside the head buffer of the skb
+ *  marking the start of the data to be CRC'ed
+ *
+ * payload_ptr must always point to an address in the skb head buffer and not to
+ * a fragment.
+ */
+__be32 batadv_skb_crc32(struct sk_buff *skb, u8 *payload_ptr)
+{
+	u32 crc = 0;
+	unsigned int from;
+	unsigned int to = skb->len;
+	struct skb_seq_state st;
+	const u8 *data;
+	unsigned int len;
+	unsigned int consumed = 0;
+
+	from = (unsigned int)(payload_ptr - skb->data);
+
+	skb_prepare_seq_read(skb, from, to, &st);
+	while ((len = skb_seq_read(consumed, &data, &st)) != 0) {
+		crc = crc32c(crc, data, len);
+		consumed += len;
+	}
+	skb_abort_seq_read(&st);
+
+	return htonl(crc);
+}
+
 static int batadv_param_set_ra(const char *val, const struct kernel_param *kp)
 {
 	struct batadv_algo_ops *bat_algo_ops;
diff --git a/net/batman-adv/main.h b/net/batman-adv/main.h
index d57b746219de..2f85577086a7 100644
--- a/net/batman-adv/main.h
+++ b/net/batman-adv/main.h
@@ -26,7 +26,7 @@
 #define BATADV_DRIVER_DEVICE "batman-adv"
 
 #ifndef BATADV_SOURCE_VERSION
-#define BATADV_SOURCE_VERSION "2012.4.0"
+#define BATADV_SOURCE_VERSION "2012.5.0"
 #endif
 
 /* B.A.T.M.A.N. parameters */
@@ -44,6 +44,7 @@
 #define BATADV_TT_LOCAL_TIMEOUT 3600000 /* in milliseconds */
 #define BATADV_TT_CLIENT_ROAM_TIMEOUT 600000 /* in milliseconds */
 #define BATADV_TT_CLIENT_TEMP_TIMEOUT 600000 /* in milliseconds */
+#define BATADV_DAT_ENTRY_TIMEOUT (5*60000) /* 5 mins in milliseconds */
 /* sliding packet range of received originator messages in sequence numbers
  * (should be a multiple of our word size)
  */
@@ -73,6 +74,11 @@
 
 #define BATADV_LOG_BUF_LEN 8192	  /* has to be a power of 2 */
 
+/* msecs after which an ARP_REQUEST is sent in broadcast as fallback */
+#define ARP_REQ_DELAY 250
+/* numbers of originator to contact for any PUT/GET DHT operation */
+#define BATADV_DAT_CANDIDATES_NUM 3
+
 #define BATADV_VIS_INTERVAL 5000	/* 5 seconds */
 
 /* how much worse secondary interfaces may be to be considered as bonding
@@ -89,6 +95,7 @@
 #define BATADV_BLA_PERIOD_LENGTH	10000	/* 10 seconds */
 #define BATADV_BLA_BACKBONE_TIMEOUT	(BATADV_BLA_PERIOD_LENGTH * 3)
 #define BATADV_BLA_CLAIM_TIMEOUT	(BATADV_BLA_PERIOD_LENGTH * 10)
+#define BATADV_BLA_WAIT_PERIODS		3
 
 #define BATADV_DUPLIST_SIZE		16
 #define BATADV_DUPLIST_TIMEOUT		500	/* 500 ms */
@@ -117,6 +124,9 @@ enum batadv_uev_type {
 
 #define BATADV_GW_THRESHOLD	50
 
+#define BATADV_DAT_CANDIDATE_NOT_FOUND	0
+#define BATADV_DAT_CANDIDATE_ORIG	1
+
 /* Debug Messages */
 #ifdef pr_fmt
 #undef pr_fmt
@@ -150,9 +160,9 @@ extern struct workqueue_struct *batadv_event_workqueue;
 
 int batadv_mesh_init(struct net_device *soft_iface);
 void batadv_mesh_free(struct net_device *soft_iface);
-void batadv_inc_module_count(void);
-void batadv_dec_module_count(void);
 int batadv_is_my_mac(const uint8_t *addr);
+struct batadv_hard_iface *
+batadv_seq_print_text_primary_if_get(struct seq_file *seq);
 int batadv_batman_skb_recv(struct sk_buff *skb, struct net_device *dev,
 			   struct packet_type *ptype,
 			   struct net_device *orig_dev);
@@ -164,14 +174,24 @@ void batadv_recv_handler_unregister(uint8_t packet_type);
 int batadv_algo_register(struct batadv_algo_ops *bat_algo_ops);
 int batadv_algo_select(struct batadv_priv *bat_priv, char *name);
 int batadv_algo_seq_print_text(struct seq_file *seq, void *offset);
+__be32 batadv_skb_crc32(struct sk_buff *skb, u8 *payload_ptr);
 
-/* all messages related to routing / flooding / broadcasting / etc */
+/**
+ * enum batadv_dbg_level - available log levels
+ * @BATADV_DBG_BATMAN: OGM and TQ computations related messages
+ * @BATADV_DBG_ROUTES: route added / changed / deleted
+ * @BATADV_DBG_TT: translation table messages
+ * @BATADV_DBG_BLA: bridge loop avoidance messages
+ * @BATADV_DBG_DAT: ARP snooping and DAT related messages
+ * @BATADV_DBG_ALL: the union of all the above log levels
+ */
 enum batadv_dbg_level {
 	BATADV_DBG_BATMAN = BIT(0),
-	BATADV_DBG_ROUTES = BIT(1), /* route added / changed / deleted */
-	BATADV_DBG_TT	  = BIT(2), /* translation table operations */
-	BATADV_DBG_BLA    = BIT(3), /* bridge loop avoidance */
-	BATADV_DBG_ALL    = 15,
+	BATADV_DBG_ROUTES = BIT(1),
+	BATADV_DBG_TT	  = BIT(2),
+	BATADV_DBG_BLA    = BIT(3),
+	BATADV_DBG_DAT    = BIT(4),
+	BATADV_DBG_ALL    = 31,
 };
 
 #ifdef CONFIG_BATMAN_ADV_DEBUG
diff --git a/net/batman-adv/originator.c b/net/batman-adv/originator.c
index ac9bdf8f80a6..8c32cf1c2dec 100644
--- a/net/batman-adv/originator.c
+++ b/net/batman-adv/originator.c
@@ -18,6 +18,7 @@
  */
 
 #include "main.h"
+#include "distributed-arp-table.h"
 #include "originator.h"
 #include "hash.h"
 #include "translation-table.h"
@@ -220,9 +221,9 @@ struct batadv_orig_node *batadv_get_orig_node(struct batadv_priv *bat_priv,
 	atomic_set(&orig_node->refcount, 2);
 
 	orig_node->tt_initialised = false;
-	orig_node->tt_poss_change = false;
 	orig_node->bat_priv = bat_priv;
 	memcpy(orig_node->orig, addr, ETH_ALEN);
+	batadv_dat_init_orig_node_addr(orig_node);
 	orig_node->router = NULL;
 	orig_node->tt_crc = 0;
 	atomic_set(&orig_node->last_ttvn, 0);
@@ -415,23 +416,10 @@ int batadv_orig_seq_print_text(struct seq_file *seq, void *offset)
 	int last_seen_msecs;
 	unsigned long last_seen_jiffies;
 	uint32_t i;
-	int ret = 0;
 
-	primary_if = batadv_primary_if_get_selected(bat_priv);
-
-	if (!primary_if) {
-		ret = seq_printf(seq,
-				 "BATMAN mesh %s disabled - please specify interfaces to enable it\n",
-				 net_dev->name);
-		goto out;
-	}
-
-	if (primary_if->if_status != BATADV_IF_ACTIVE) {
-		ret = seq_printf(seq,
-				 "BATMAN mesh %s disabled - primary interface not active\n",
-				 net_dev->name);
+	primary_if = batadv_seq_print_text_primary_if_get(seq);
+	if (!primary_if)
 		goto out;
-	}
 
 	seq_printf(seq, "[B.A.T.M.A.N. adv %s, MainIF/MAC: %s/%pM (%s)]\n",
 		   BATADV_SOURCE_VERSION, primary_if->net_dev->name,
@@ -485,7 +473,7 @@ next:
 out:
 	if (primary_if)
 		batadv_hardif_free_ref(primary_if);
-	return ret;
+	return 0;
 }
 
 static int batadv_orig_node_add_if(struct batadv_orig_node *orig_node,
diff --git a/net/batman-adv/packet.h b/net/batman-adv/packet.h
index 2d23a14c220e..cb6405bf755c 100644
--- a/net/batman-adv/packet.h
+++ b/net/batman-adv/packet.h
@@ -20,17 +20,30 @@
 #ifndef _NET_BATMAN_ADV_PACKET_H_
 #define _NET_BATMAN_ADV_PACKET_H_
 
-#define BATADV_ETH_P_BATMAN  0x4305 /* unofficial/not registered Ethertype */
-
 enum batadv_packettype {
-	BATADV_IV_OGM	    = 0x01,
-	BATADV_ICMP	    = 0x02,
-	BATADV_UNICAST	    = 0x03,
-	BATADV_BCAST	    = 0x04,
-	BATADV_VIS	    = 0x05,
-	BATADV_UNICAST_FRAG = 0x06,
-	BATADV_TT_QUERY	    = 0x07,
-	BATADV_ROAM_ADV	    = 0x08,
+	BATADV_IV_OGM		= 0x01,
+	BATADV_ICMP		= 0x02,
+	BATADV_UNICAST		= 0x03,
+	BATADV_BCAST		= 0x04,
+	BATADV_VIS		= 0x05,
+	BATADV_UNICAST_FRAG	= 0x06,
+	BATADV_TT_QUERY		= 0x07,
+	BATADV_ROAM_ADV		= 0x08,
+	BATADV_UNICAST_4ADDR	= 0x09,
+};
+
+/**
+ * enum batadv_subtype - packet subtype for unicast4addr
+ * @BATADV_P_DATA: user payload
+ * @BATADV_P_DAT_DHT_GET: DHT request message
+ * @BATADV_P_DAT_DHT_PUT: DHT store message
+ * @BATADV_P_DAT_CACHE_REPLY: ARP reply generated by DAT
+ */
+enum batadv_subtype {
+	BATADV_P_DATA			= 0x01,
+	BATADV_P_DAT_DHT_GET		= 0x02,
+	BATADV_P_DAT_DHT_PUT		= 0x03,
+	BATADV_P_DAT_CACHE_REPLY	= 0x04,
 };
 
 /* this file is included by batctl which needs these defines */
@@ -106,13 +119,16 @@ struct batadv_bla_claim_dst {
 	uint8_t magic[3];	/* FF:43:05 */
 	uint8_t type;		/* bla_claimframe */
 	__be16 group;		/* group id */
-} __packed;
+};
 
 struct batadv_header {
 	uint8_t  packet_type;
 	uint8_t  version;  /* batman version field */
 	uint8_t  ttl;
-} __packed;
+	/* the parent struct has to add a byte after the header to make
+	 * everything 4 bytes aligned again
+	 */
+};
 
 struct batadv_ogm_packet {
 	struct batadv_header header;
@@ -137,7 +153,7 @@ struct batadv_icmp_packet {
 	__be16   seqno;
 	uint8_t  uid;
 	uint8_t  reserved;
-} __packed;
+};
 
 #define BATADV_RR_LEN 16
 
@@ -153,13 +169,44 @@ struct batadv_icmp_packet_rr {
 	uint8_t  uid;
 	uint8_t  rr_cur;
 	uint8_t  rr[BATADV_RR_LEN][ETH_ALEN];
-} __packed;
+};
+
+/* All packet headers in front of an ethernet header have to be completely
+ * divisible by 2 but not by 4 to make the payload after the ethernet
+ * header again 4 bytes boundary aligned.
+ *
+ * A packing of 2 is necessary to avoid extra padding at the end of the struct
+ * caused by a structure member which is larger than two bytes. Otherwise
+ * the structure would not fulfill the previously mentioned rule to avoid the
+ * misalignment of the payload after the ethernet header. It may also lead to
+ * leakage of information when the padding it not initialized before sending.
+ */
+#pragma pack(2)
 
 struct batadv_unicast_packet {
 	struct batadv_header header;
 	uint8_t  ttvn; /* destination translation table version number */
 	uint8_t  dest[ETH_ALEN];
-} __packed;
+	/* "4 bytes boundary + 2 bytes" long to make the payload after the
+	 * following ethernet header again 4 bytes boundary aligned
+	 */
+};
+
+/**
+ * struct batadv_unicast_4addr_packet - extended unicast packet
+ * @u: common unicast packet header
+ * @src: address of the source
+ * @subtype: packet subtype
+ */
+struct batadv_unicast_4addr_packet {
+	struct batadv_unicast_packet u;
+	uint8_t src[ETH_ALEN];
+	uint8_t subtype;
+	uint8_t reserved;
+	/* "4 bytes boundary + 2 bytes" long to make the payload after the
+	 * following ethernet header again 4 bytes boundary aligned
+	 */
+};
 
 struct batadv_unicast_frag_packet {
 	struct batadv_header header;
@@ -176,7 +223,12 @@ struct batadv_bcast_packet {
 	uint8_t  reserved;
 	__be32   seqno;
 	uint8_t  orig[ETH_ALEN];
-} __packed;
+	/* "4 bytes boundary + 2 bytes" long to make the payload after the
+	 * following ethernet header again 4 bytes boundary aligned
+	 */
+};
+
+#pragma pack()
 
 struct batadv_vis_packet {
 	struct batadv_header header;
@@ -187,7 +239,7 @@ struct batadv_vis_packet {
 	uint8_t  vis_orig[ETH_ALEN];	/* originator reporting its neighbors */
 	uint8_t  target_orig[ETH_ALEN]; /* who should receive this packet */
 	uint8_t  sender_orig[ETH_ALEN]; /* who sent or forwarded this packet */
-} __packed;
+};
 
 struct batadv_tt_query_packet {
 	struct batadv_header header;
diff --git a/net/batman-adv/routing.c b/net/batman-adv/routing.c
index 376b4cc6ca82..1aa1722d0187 100644
--- a/net/batman-adv/routing.c
+++ b/net/batman-adv/routing.c
@@ -28,6 +28,7 @@
 #include "vis.h"
 #include "unicast.h"
 #include "bridge_loop_avoidance.h"
+#include "distributed-arp-table.h"
 
 static int batadv_route_unicast_packet(struct sk_buff *skb,
 				       struct batadv_hard_iface *recv_if);
@@ -284,7 +285,6 @@ static int batadv_recv_my_icmp_packet(struct batadv_priv *bat_priv,
 {
 	struct batadv_hard_iface *primary_if = NULL;
 	struct batadv_orig_node *orig_node = NULL;
-	struct batadv_neigh_node *router = NULL;
 	struct batadv_icmp_packet_rr *icmp_packet;
 	int ret = NET_RX_DROP;
 
@@ -306,10 +306,6 @@ static int batadv_recv_my_icmp_packet(struct batadv_priv *bat_priv,
 	if (!orig_node)
 		goto out;
 
-	router = batadv_orig_node_get_router(orig_node);
-	if (!router)
-		goto out;
-
 	/* create a copy of the skb, if needed, to modify it. */
 	if (skb_cow(skb, ETH_HLEN) < 0)
 		goto out;
@@ -321,14 +317,12 @@ static int batadv_recv_my_icmp_packet(struct batadv_priv *bat_priv,
 	icmp_packet->msg_type = BATADV_ECHO_REPLY;
 	icmp_packet->header.ttl = BATADV_TTL;
 
-	batadv_send_skb_packet(skb, router->if_incoming, router->addr);
-	ret = NET_RX_SUCCESS;
+	if (batadv_send_skb_to_orig(skb, orig_node, NULL))
+		ret = NET_RX_SUCCESS;
 
 out:
 	if (primary_if)
 		batadv_hardif_free_ref(primary_if);
-	if (router)
-		batadv_neigh_node_free_ref(router);
 	if (orig_node)
 		batadv_orig_node_free_ref(orig_node);
 	return ret;
@@ -339,7 +333,6 @@ static int batadv_recv_icmp_ttl_exceeded(struct batadv_priv *bat_priv,
 {
 	struct batadv_hard_iface *primary_if = NULL;
 	struct batadv_orig_node *orig_node = NULL;
-	struct batadv_neigh_node *router = NULL;
 	struct batadv_icmp_packet *icmp_packet;
 	int ret = NET_RX_DROP;
 
@@ -361,10 +354,6 @@ static int batadv_recv_icmp_ttl_exceeded(struct batadv_priv *bat_priv,
 	if (!orig_node)
 		goto out;
 
-	router = batadv_orig_node_get_router(orig_node);
-	if (!router)
-		goto out;
-
 	/* create a copy of the skb, if needed, to modify it. */
 	if (skb_cow(skb, ETH_HLEN) < 0)
 		goto out;
@@ -376,14 +365,12 @@ static int batadv_recv_icmp_ttl_exceeded(struct batadv_priv *bat_priv,
 	icmp_packet->msg_type = BATADV_TTL_EXCEEDED;
 	icmp_packet->header.ttl = BATADV_TTL;
 
-	batadv_send_skb_packet(skb, router->if_incoming, router->addr);
-	ret = NET_RX_SUCCESS;
+	if (batadv_send_skb_to_orig(skb, orig_node, NULL))
+		ret = NET_RX_SUCCESS;
 
 out:
 	if (primary_if)
 		batadv_hardif_free_ref(primary_if);
-	if (router)
-		batadv_neigh_node_free_ref(router);
 	if (orig_node)
 		batadv_orig_node_free_ref(orig_node);
 	return ret;
@@ -397,7 +384,6 @@ int batadv_recv_icmp_packet(struct sk_buff *skb,
 	struct batadv_icmp_packet_rr *icmp_packet;
 	struct ethhdr *ethhdr;
 	struct batadv_orig_node *orig_node = NULL;
-	struct batadv_neigh_node *router = NULL;
 	int hdr_size = sizeof(struct batadv_icmp_packet);
 	int ret = NET_RX_DROP;
 
@@ -446,10 +432,6 @@ int batadv_recv_icmp_packet(struct sk_buff *skb,
 	if (!orig_node)
 		goto out;
 
-	router = batadv_orig_node_get_router(orig_node);
-	if (!router)
-		goto out;
-
 	/* create a copy of the skb, if needed, to modify it. */
 	if (skb_cow(skb, ETH_HLEN) < 0)
 		goto out;
@@ -460,12 +442,10 @@ int batadv_recv_icmp_packet(struct sk_buff *skb,
 	icmp_packet->header.ttl--;
 
 	/* route it */
-	batadv_send_skb_packet(skb, router->if_incoming, router->addr);
-	ret = NET_RX_SUCCESS;
+	if (batadv_send_skb_to_orig(skb, orig_node, recv_if))
+		ret = NET_RX_SUCCESS;
 
 out:
-	if (router)
-		batadv_neigh_node_free_ref(router);
 	if (orig_node)
 		batadv_orig_node_free_ref(orig_node);
 	return ret;
@@ -549,25 +529,18 @@ batadv_find_ifalter_router(struct batadv_orig_node *primary_orig,
 		if (tmp_neigh_node->if_incoming == recv_if)
 			continue;
 
-		if (!atomic_inc_not_zero(&tmp_neigh_node->refcount))
+		if (router && tmp_neigh_node->tq_avg <= router->tq_avg)
 			continue;
 
-		/* if we don't have a router yet
-		 * or this one is better, choose it.
-		 */
-		if ((!router) ||
-		    (tmp_neigh_node->tq_avg > router->tq_avg)) {
-			/* decrement refcount of
-			 * previously selected router
-			 */
-			if (router)
-				batadv_neigh_node_free_ref(router);
+		if (!atomic_inc_not_zero(&tmp_neigh_node->refcount))
+			continue;
 
-			router = tmp_neigh_node;
-			atomic_inc_not_zero(&router->refcount);
-		}
+		/* decrement refcount of previously selected router */
+		if (router)
+			batadv_neigh_node_free_ref(router);
 
-		batadv_neigh_node_free_ref(tmp_neigh_node);
+		/* we found a better router (or at least one valid router) */
+		router = tmp_neigh_node;
 	}
 
 	/* use the first candidate if nothing was found. */
@@ -687,21 +660,8 @@ int batadv_recv_roam_adv(struct sk_buff *skb, struct batadv_hard_iface *recv_if)
 	struct batadv_priv *bat_priv = netdev_priv(recv_if->soft_iface);
 	struct batadv_roam_adv_packet *roam_adv_packet;
 	struct batadv_orig_node *orig_node;
-	struct ethhdr *ethhdr;
-
-	/* drop packet if it has not necessary minimum size */
-	if (unlikely(!pskb_may_pull(skb,
-				    sizeof(struct batadv_roam_adv_packet))))
-		goto out;
-
-	ethhdr = (struct ethhdr *)skb_mac_header(skb);
-
-	/* packet with unicast indication but broadcast recipient */
-	if (is_broadcast_ether_addr(ethhdr->h_dest))
-		goto out;
 
-	/* packet with broadcast sender address */
-	if (is_broadcast_ether_addr(ethhdr->h_source))
+	if (batadv_check_unicast_packet(skb, sizeof(*roam_adv_packet)) < 0)
 		goto out;
 
 	batadv_inc_counter(bat_priv, BATADV_CNT_TT_ROAM_ADV_RX);
@@ -730,12 +690,6 @@ int batadv_recv_roam_adv(struct sk_buff *skb, struct batadv_hard_iface *recv_if)
 			     BATADV_TT_CLIENT_ROAM,
 			     atomic_read(&orig_node->last_ttvn) + 1);
 
-	/* Roaming phase starts: I have new information but the ttvn has not
-	 * been incremented yet. This flag will make me check all the incoming
-	 * packets for the correct destination.
-	 */
-	bat_priv->tt.poss_change = true;
-
 	batadv_orig_node_free_ref(orig_node);
 out:
 	/* returning NET_RX_DROP will make the caller function kfree the skb */
@@ -907,8 +861,8 @@ static int batadv_route_unicast_packet(struct sk_buff *skb,
 			   skb->len + ETH_HLEN);
 
 	/* route it */
-	batadv_send_skb_packet(skb, neigh_node->if_incoming, neigh_node->addr);
-	ret = NET_RX_SUCCESS;
+	if (batadv_send_skb_to_orig(skb, orig_node, recv_if))
+		ret = NET_RX_SUCCESS;
 
 out:
 	if (neigh_node)
@@ -918,80 +872,161 @@ out:
 	return ret;
 }
 
+/**
+ * batadv_reroute_unicast_packet - update the unicast header for re-routing
+ * @bat_priv: the bat priv with all the soft interface information
+ * @unicast_packet: the unicast header to be updated
+ * @dst_addr: the payload destination
+ *
+ * Search the translation table for dst_addr and update the unicast header with
+ * the new corresponding information (originator address where the destination
+ * client currently is and its known TTVN)
+ *
+ * Returns true if the packet header has been updated, false otherwise
+ */
+static bool
+batadv_reroute_unicast_packet(struct batadv_priv *bat_priv,
+			      struct batadv_unicast_packet *unicast_packet,
+			      uint8_t *dst_addr)
+{
+	struct batadv_orig_node *orig_node = NULL;
+	struct batadv_hard_iface *primary_if = NULL;
+	bool ret = false;
+	uint8_t *orig_addr, orig_ttvn;
+
+	if (batadv_is_my_client(bat_priv, dst_addr)) {
+		primary_if = batadv_primary_if_get_selected(bat_priv);
+		if (!primary_if)
+			goto out;
+		orig_addr = primary_if->net_dev->dev_addr;
+		orig_ttvn = (uint8_t)atomic_read(&bat_priv->tt.vn);
+	} else {
+		orig_node = batadv_transtable_search(bat_priv, NULL, dst_addr);
+		if (!orig_node)
+			goto out;
+
+		if (batadv_compare_eth(orig_node->orig, unicast_packet->dest))
+			goto out;
+
+		orig_addr = orig_node->orig;
+		orig_ttvn = (uint8_t)atomic_read(&orig_node->last_ttvn);
+	}
+
+	/* update the packet header */
+	memcpy(unicast_packet->dest, orig_addr, ETH_ALEN);
+	unicast_packet->ttvn = orig_ttvn;
+
+	ret = true;
+out:
+	if (primary_if)
+		batadv_hardif_free_ref(primary_if);
+	if (orig_node)
+		batadv_orig_node_free_ref(orig_node);
+
+	return ret;
+}
+
 static int batadv_check_unicast_ttvn(struct batadv_priv *bat_priv,
 				     struct sk_buff *skb) {
-	uint8_t curr_ttvn;
+	uint8_t curr_ttvn, old_ttvn;
 	struct batadv_orig_node *orig_node;
 	struct ethhdr *ethhdr;
 	struct batadv_hard_iface *primary_if;
 	struct batadv_unicast_packet *unicast_packet;
-	bool tt_poss_change;
 	int is_old_ttvn;
 
-	/* I could need to modify it */
-	if (skb_cow(skb, sizeof(struct batadv_unicast_packet)) < 0)
+	/* check if there is enough data before accessing it */
+	if (pskb_may_pull(skb, sizeof(*unicast_packet) + ETH_HLEN) < 0)
+		return 0;
+
+	/* create a copy of the skb (in case of for re-routing) to modify it. */
+	if (skb_cow(skb, sizeof(*unicast_packet)) < 0)
 		return 0;
 
 	unicast_packet = (struct batadv_unicast_packet *)skb->data;
+	ethhdr = (struct ethhdr *)(skb->data + sizeof(*unicast_packet));
 
-	if (batadv_is_my_mac(unicast_packet->dest)) {
-		tt_poss_change = bat_priv->tt.poss_change;
-		curr_ttvn = (uint8_t)atomic_read(&bat_priv->tt.vn);
-	} else {
+	/* check if the destination client was served by this node and it is now
+	 * roaming. In this case, it means that the node has got a ROAM_ADV
+	 * message and that it knows the new destination in the mesh to re-route
+	 * the packet to
+	 */
+	if (batadv_tt_local_client_is_roaming(bat_priv, ethhdr->h_dest)) {
+		if (batadv_reroute_unicast_packet(bat_priv, unicast_packet,
+						  ethhdr->h_dest))
+			net_ratelimited_function(batadv_dbg, BATADV_DBG_TT,
+						 bat_priv,
+						 "Rerouting unicast packet to %pM (dst=%pM): Local Roaming\n",
+						 unicast_packet->dest,
+						 ethhdr->h_dest);
+		/* at this point the mesh destination should have been
+		 * substituted with the originator address found in the global
+		 * table. If not, let the packet go untouched anyway because
+		 * there is nothing the node can do
+		 */
+		return 1;
+	}
+
+	/* retrieve the TTVN known by this node for the packet destination. This
+	 * value is used later to check if the node which sent (or re-routed
+	 * last time) the packet had an updated information or not
+	 */
+	curr_ttvn = (uint8_t)atomic_read(&bat_priv->tt.vn);
+	if (!batadv_is_my_mac(unicast_packet->dest)) {
 		orig_node = batadv_orig_hash_find(bat_priv,
 						  unicast_packet->dest);
-
+		/* if it is not possible to find the orig_node representing the
+		 * destination, the packet can immediately be dropped as it will
+		 * not be possible to deliver it
+		 */
 		if (!orig_node)
 			return 0;
 
 		curr_ttvn = (uint8_t)atomic_read(&orig_node->last_ttvn);
-		tt_poss_change = orig_node->tt_poss_change;
 		batadv_orig_node_free_ref(orig_node);
 	}
 
-	/* Check whether I have to reroute the packet */
+	/* check if the TTVN contained in the packet is fresher than what the
+	 * node knows
+	 */
 	is_old_ttvn = batadv_seq_before(unicast_packet->ttvn, curr_ttvn);
-	if (is_old_ttvn || tt_poss_change) {
-		/* check if there is enough data before accessing it */
-		if (pskb_may_pull(skb, sizeof(struct batadv_unicast_packet) +
-				  ETH_HLEN) < 0)
-			return 0;
+	if (!is_old_ttvn)
+		return 1;
 
-		ethhdr = (struct ethhdr *)(skb->data + sizeof(*unicast_packet));
+	old_ttvn = unicast_packet->ttvn;
+	/* the packet was forged based on outdated network information. Its
+	 * destination can possibly be updated and forwarded towards the new
+	 * target host
+	 */
+	if (batadv_reroute_unicast_packet(bat_priv, unicast_packet,
+					  ethhdr->h_dest)) {
+		net_ratelimited_function(batadv_dbg, BATADV_DBG_TT, bat_priv,
+					 "Rerouting unicast packet to %pM (dst=%pM): TTVN mismatch old_ttvn=%u new_ttvn=%u\n",
+					 unicast_packet->dest, ethhdr->h_dest,
+					 old_ttvn, curr_ttvn);
+		return 1;
+	}
 
-		/* we don't have an updated route for this client, so we should
-		 * not try to reroute the packet!!
-		 */
-		if (batadv_tt_global_client_is_roaming(bat_priv,
-						       ethhdr->h_dest))
-			return 1;
+	/* the packet has not been re-routed: either the destination is
+	 * currently served by this node or there is no destination at all and
+	 * it is possible to drop the packet
+	 */
+	if (!batadv_is_my_client(bat_priv, ethhdr->h_dest))
+		return 0;
 
-		orig_node = batadv_transtable_search(bat_priv, NULL,
-						     ethhdr->h_dest);
-
-		if (!orig_node) {
-			if (!batadv_is_my_client(bat_priv, ethhdr->h_dest))
-				return 0;
-			primary_if = batadv_primary_if_get_selected(bat_priv);
-			if (!primary_if)
-				return 0;
-			memcpy(unicast_packet->dest,
-			       primary_if->net_dev->dev_addr, ETH_ALEN);
-			batadv_hardif_free_ref(primary_if);
-		} else {
-			memcpy(unicast_packet->dest, orig_node->orig,
-			       ETH_ALEN);
-			curr_ttvn = (uint8_t)atomic_read(&orig_node->last_ttvn);
-			batadv_orig_node_free_ref(orig_node);
-		}
+	/* update the header in order to let the packet be delivered to this
+	 * node's soft interface
+	 */
+	primary_if = batadv_primary_if_get_selected(bat_priv);
+	if (!primary_if)
+		return 0;
 
-		batadv_dbg(BATADV_DBG_ROUTES, bat_priv,
-			   "TTVN mismatch (old_ttvn %u new_ttvn %u)! Rerouting unicast packet (for %pM) to %pM\n",
-			   unicast_packet->ttvn, curr_ttvn, ethhdr->h_dest,
-			   unicast_packet->dest);
+	memcpy(unicast_packet->dest, primary_if->net_dev->dev_addr, ETH_ALEN);
+
+	batadv_hardif_free_ref(primary_if);
+
+	unicast_packet->ttvn = curr_ttvn;
 
-		unicast_packet->ttvn = curr_ttvn;
-	}
 	return 1;
 }
 
@@ -1000,7 +1035,19 @@ int batadv_recv_unicast_packet(struct sk_buff *skb,
 {
 	struct batadv_priv *bat_priv = netdev_priv(recv_if->soft_iface);
 	struct batadv_unicast_packet *unicast_packet;
+	struct batadv_unicast_4addr_packet *unicast_4addr_packet;
+	uint8_t *orig_addr;
+	struct batadv_orig_node *orig_node = NULL;
 	int hdr_size = sizeof(*unicast_packet);
+	bool is4addr;
+
+	unicast_packet = (struct batadv_unicast_packet *)skb->data;
+	unicast_4addr_packet = (struct batadv_unicast_4addr_packet *)skb->data;
+
+	is4addr = unicast_packet->header.packet_type == BATADV_UNICAST_4ADDR;
+	/* the caller function should have already pulled 2 bytes */
+	if (is4addr)
+		hdr_size = sizeof(*unicast_4addr_packet);
 
 	if (batadv_check_unicast_packet(skb, hdr_size) < 0)
 		return NET_RX_DROP;
@@ -1008,12 +1055,28 @@ int batadv_recv_unicast_packet(struct sk_buff *skb,
 	if (!batadv_check_unicast_ttvn(bat_priv, skb))
 		return NET_RX_DROP;
 
-	unicast_packet = (struct batadv_unicast_packet *)skb->data;
-
 	/* packet for me */
 	if (batadv_is_my_mac(unicast_packet->dest)) {
+		if (is4addr) {
+			batadv_dat_inc_counter(bat_priv,
+					       unicast_4addr_packet->subtype);
+			orig_addr = unicast_4addr_packet->src;
+			orig_node = batadv_orig_hash_find(bat_priv, orig_addr);
+		}
+
+		if (batadv_dat_snoop_incoming_arp_request(bat_priv, skb,
+							  hdr_size))
+			goto rx_success;
+		if (batadv_dat_snoop_incoming_arp_reply(bat_priv, skb,
+							hdr_size))
+			goto rx_success;
+
 		batadv_interface_rx(recv_if->soft_iface, skb, recv_if, hdr_size,
-				    NULL);
+				    orig_node);
+
+rx_success:
+		if (orig_node)
+			batadv_orig_node_free_ref(orig_node);
 
 		return NET_RX_SUCCESS;
 	}
@@ -1050,8 +1113,17 @@ int batadv_recv_ucast_frag_packet(struct sk_buff *skb,
 		if (!new_skb)
 			return NET_RX_SUCCESS;
 
+		if (batadv_dat_snoop_incoming_arp_request(bat_priv, new_skb,
+							  hdr_size))
+			goto rx_success;
+		if (batadv_dat_snoop_incoming_arp_reply(bat_priv, new_skb,
+							hdr_size))
+			goto rx_success;
+
 		batadv_interface_rx(recv_if->soft_iface, new_skb, recv_if,
 				    sizeof(struct batadv_unicast_packet), NULL);
+
+rx_success:
 		return NET_RX_SUCCESS;
 	}
 
@@ -1124,14 +1196,8 @@ int batadv_recv_bcast_packet(struct sk_buff *skb,
 
 	spin_unlock_bh(&orig_node->bcast_seqno_lock);
 
-	/* keep skb linear for crc calculation */
-	if (skb_linearize(skb) < 0)
-		goto out;
-
-	bcast_packet = (struct batadv_bcast_packet *)skb->data;
-
 	/* check whether this has been sent by another originator before */
-	if (batadv_bla_check_bcast_duplist(bat_priv, bcast_packet, skb->len))
+	if (batadv_bla_check_bcast_duplist(bat_priv, skb))
 		goto out;
 
 	/* rebroadcast packet */
@@ -1143,9 +1209,16 @@ int batadv_recv_bcast_packet(struct sk_buff *skb,
 	if (batadv_bla_is_backbone_gw(skb, orig_node, hdr_size))
 		goto out;
 
+	if (batadv_dat_snoop_incoming_arp_request(bat_priv, skb, hdr_size))
+		goto rx_success;
+	if (batadv_dat_snoop_incoming_arp_reply(bat_priv, skb, hdr_size))
+		goto rx_success;
+
 	/* broadcast for me */
 	batadv_interface_rx(recv_if->soft_iface, skb, recv_if, hdr_size,
 			    orig_node);
+
+rx_success:
 	ret = NET_RX_SUCCESS;
 	goto out;
 
diff --git a/net/batman-adv/send.c b/net/batman-adv/send.c
index 570a8bce0364..4425af9dad40 100644
--- a/net/batman-adv/send.c
+++ b/net/batman-adv/send.c
@@ -18,6 +18,7 @@
  */
 
 #include "main.h"
+#include "distributed-arp-table.h"
 #include "send.h"
 #include "routing.h"
 #include "translation-table.h"
@@ -27,6 +28,8 @@
 #include "gateway_common.h"
 #include "originator.h"
 
+#include <linux/if_ether.h>
+
 static void batadv_send_outstanding_bcast_packet(struct work_struct *work);
 
 /* send out an already prepared packet to the given address via the
@@ -59,11 +62,11 @@ int batadv_send_skb_packet(struct sk_buff *skb,
 	ethhdr = (struct ethhdr *)skb_mac_header(skb);
 	memcpy(ethhdr->h_source, hard_iface->net_dev->dev_addr, ETH_ALEN);
 	memcpy(ethhdr->h_dest, dst_addr, ETH_ALEN);
-	ethhdr->h_proto = __constant_htons(BATADV_ETH_P_BATMAN);
+	ethhdr->h_proto = __constant_htons(ETH_P_BATMAN);
 
 	skb_set_network_header(skb, ETH_HLEN);
 	skb->priority = TC_PRIO_CONTROL;
-	skb->protocol = __constant_htons(BATADV_ETH_P_BATMAN);
+	skb->protocol = __constant_htons(ETH_P_BATMAN);
 
 	skb->dev = hard_iface->net_dev;
 
@@ -77,6 +80,39 @@ send_skb_err:
 	return NET_XMIT_DROP;
 }
 
+/**
+ * batadv_send_skb_to_orig - Lookup next-hop and transmit skb.
+ * @skb: Packet to be transmitted.
+ * @orig_node: Final destination of the packet.
+ * @recv_if: Interface used when receiving the packet (can be NULL).
+ *
+ * Looks up the best next-hop towards the passed originator and passes the
+ * skb on for preparation of MAC header. If the packet originated from this
+ * host, NULL can be passed as recv_if and no interface alternating is
+ * attempted.
+ *
+ * Returns TRUE on success; FALSE otherwise.
+ */
+bool batadv_send_skb_to_orig(struct sk_buff *skb,
+			     struct batadv_orig_node *orig_node,
+			     struct batadv_hard_iface *recv_if)
+{
+	struct batadv_priv *bat_priv = orig_node->bat_priv;
+	struct batadv_neigh_node *neigh_node;
+
+	/* batadv_find_router() increases neigh_nodes refcount if found. */
+	neigh_node = batadv_find_router(bat_priv, orig_node, recv_if);
+	if (!neigh_node)
+		return false;
+
+	/* route it */
+	batadv_send_skb_packet(skb, neigh_node->if_incoming, neigh_node->addr);
+
+	batadv_neigh_node_free_ref(neigh_node);
+
+	return true;
+}
+
 void batadv_schedule_bat_ogm(struct batadv_hard_iface *hard_iface)
 {
 	struct batadv_priv *bat_priv = netdev_priv(hard_iface->soft_iface);
@@ -209,6 +245,9 @@ static void batadv_send_outstanding_bcast_packet(struct work_struct *work)
 	if (atomic_read(&bat_priv->mesh_state) == BATADV_MESH_DEACTIVATING)
 		goto out;
 
+	if (batadv_dat_drop_broadcast_packet(bat_priv, forw_packet))
+		goto out;
+
 	/* rebroadcast packet */
 	rcu_read_lock();
 	list_for_each_entry_rcu(hard_iface, &batadv_hardif_list, list) {
diff --git a/net/batman-adv/send.h b/net/batman-adv/send.h
index 643329b787ed..0078dece1abc 100644
--- a/net/batman-adv/send.h
+++ b/net/batman-adv/send.h
@@ -23,6 +23,9 @@
 int batadv_send_skb_packet(struct sk_buff *skb,
 			   struct batadv_hard_iface *hard_iface,
 			   const uint8_t *dst_addr);
+bool batadv_send_skb_to_orig(struct sk_buff *skb,
+			     struct batadv_orig_node *orig_node,
+			     struct batadv_hard_iface *recv_if);
 void batadv_schedule_bat_ogm(struct batadv_hard_iface *hard_iface);
 int batadv_add_bcast_packet_to_list(struct batadv_priv *bat_priv,
 				    const struct sk_buff *skb,
diff --git a/net/batman-adv/soft-interface.c b/net/batman-adv/soft-interface.c
index ce0684a1fc83..6b548fde8e04 100644
--- a/net/batman-adv/soft-interface.c
+++ b/net/batman-adv/soft-interface.c
@@ -20,6 +20,7 @@
 #include "main.h"
 #include "soft-interface.h"
 #include "hard-interface.h"
+#include "distributed-arp-table.h"
 #include "routing.h"
 #include "send.h"
 #include "debugfs.h"
@@ -33,6 +34,7 @@
 #include <linux/ethtool.h>
 #include <linux/etherdevice.h>
 #include <linux/if_vlan.h>
+#include <linux/if_ether.h>
 #include "unicast.h"
 #include "bridge_loop_avoidance.h"
 
@@ -145,14 +147,17 @@ static int batadv_interface_tx(struct sk_buff *skb,
 	struct batadv_hard_iface *primary_if = NULL;
 	struct batadv_bcast_packet *bcast_packet;
 	struct vlan_ethhdr *vhdr;
-	__be16 ethertype = __constant_htons(BATADV_ETH_P_BATMAN);
-	static const uint8_t stp_addr[ETH_ALEN] = {0x01, 0x80, 0xC2, 0x00, 0x00,
-						   0x00};
+	__be16 ethertype = __constant_htons(ETH_P_BATMAN);
+	static const uint8_t stp_addr[ETH_ALEN] = {0x01, 0x80, 0xC2, 0x00,
+						   0x00, 0x00};
+	static const uint8_t ectp_addr[ETH_ALEN] = {0xCF, 0x00, 0x00, 0x00,
+						    0x00, 0x00};
 	unsigned int header_len = 0;
 	int data_len = skb->len, ret;
 	short vid __maybe_unused = -1;
 	bool do_bcast = false;
 	uint32_t seqno;
+	unsigned long brd_delay = 1;
 
 	if (atomic_read(&bat_priv->mesh_state) != BATADV_MESH_ACTIVE)
 		goto dropped;
@@ -168,7 +173,7 @@ static int batadv_interface_tx(struct sk_buff *skb,
 			break;
 
 		/* fall through */
-	case BATADV_ETH_P_BATMAN:
+	case ETH_P_BATMAN:
 		goto dropped;
 	}
 
@@ -180,10 +185,16 @@ static int batadv_interface_tx(struct sk_buff *skb,
 
 	/* don't accept stp packets. STP does not help in meshes.
 	 * better use the bridge loop avoidance ...
+	 *
+	 * The same goes for ECTP sent at least by some Cisco Switches,
+	 * it might confuse the mesh when used with bridge loop avoidance.
 	 */
 	if (batadv_compare_eth(ethhdr->h_dest, stp_addr))
 		goto dropped;
 
+	if (batadv_compare_eth(ethhdr->h_dest, ectp_addr))
+		goto dropped;
+
 	if (is_multicast_ether_addr(ethhdr->h_dest)) {
 		do_bcast = true;
 
@@ -216,6 +227,13 @@ static int batadv_interface_tx(struct sk_buff *skb,
 		if (!primary_if)
 			goto dropped;
 
+		/* in case of ARP request, we do not immediately broadcasti the
+		 * packet, instead we first wait for DAT to try to retrieve the
+		 * correct ARP entry
+		 */
+		if (batadv_dat_snoop_outgoing_arp_request(bat_priv, skb))
+			brd_delay = msecs_to_jiffies(ARP_REQ_DELAY);
+
 		if (batadv_skb_head_push(skb, sizeof(*bcast_packet)) < 0)
 			goto dropped;
 
@@ -237,7 +255,7 @@ static int batadv_interface_tx(struct sk_buff *skb,
 		seqno = atomic_inc_return(&bat_priv->bcast_seqno);
 		bcast_packet->seqno = htonl(seqno);
 
-		batadv_add_bcast_packet_to_list(bat_priv, skb, 1);
+		batadv_add_bcast_packet_to_list(bat_priv, skb, brd_delay);
 
 		/* a copy is stored in the bcast list, therefore removing
 		 * the original skb.
@@ -252,7 +270,12 @@ static int batadv_interface_tx(struct sk_buff *skb,
 				goto dropped;
 		}
 
-		ret = batadv_unicast_send_skb(skb, bat_priv);
+		if (batadv_dat_snoop_outgoing_arp_request(bat_priv, skb))
+			goto dropped;
+
+		batadv_dat_snoop_outgoing_arp_reply(bat_priv, skb);
+
+		ret = batadv_unicast_send_skb(bat_priv, skb);
 		if (ret != 0)
 			goto dropped_freed;
 	}
@@ -280,7 +303,7 @@ void batadv_interface_rx(struct net_device *soft_iface,
 	struct vlan_ethhdr *vhdr;
 	struct batadv_header *batadv_header = (struct batadv_header *)skb->data;
 	short vid __maybe_unused = -1;
-	__be16 ethertype = __constant_htons(BATADV_ETH_P_BATMAN);
+	__be16 ethertype = __constant_htons(ETH_P_BATMAN);
 	bool is_bcast;
 
 	is_bcast = (batadv_header->packet_type == BATADV_BCAST);
@@ -303,7 +326,7 @@ void batadv_interface_rx(struct net_device *soft_iface,
 			break;
 
 		/* fall through */
-	case BATADV_ETH_P_BATMAN:
+	case ETH_P_BATMAN:
 		goto dropped;
 	}
 
@@ -347,7 +370,51 @@ out:
 	return;
 }
 
+/* batman-adv network devices have devices nesting below it and are a special
+ * "super class" of normal network devices; split their locks off into a
+ * separate class since they always nest.
+ */
+static struct lock_class_key batadv_netdev_xmit_lock_key;
+static struct lock_class_key batadv_netdev_addr_lock_key;
+
+/**
+ * batadv_set_lockdep_class_one - Set lockdep class for a single tx queue
+ * @dev: device which owns the tx queue
+ * @txq: tx queue to modify
+ * @_unused: always NULL
+ */
+static void batadv_set_lockdep_class_one(struct net_device *dev,
+					 struct netdev_queue *txq,
+					 void *_unused)
+{
+	lockdep_set_class(&txq->_xmit_lock, &batadv_netdev_xmit_lock_key);
+}
+
+/**
+ * batadv_set_lockdep_class - Set txq and addr_list lockdep class
+ * @dev: network device to modify
+ */
+static void batadv_set_lockdep_class(struct net_device *dev)
+{
+	lockdep_set_class(&dev->addr_list_lock, &batadv_netdev_addr_lock_key);
+	netdev_for_each_tx_queue(dev, batadv_set_lockdep_class_one, NULL);
+}
+
+/**
+ * batadv_softif_init - Late stage initialization of soft interface
+ * @dev: registered network device to modify
+ *
+ * Returns error code on failures
+ */
+static int batadv_softif_init(struct net_device *dev)
+{
+	batadv_set_lockdep_class(dev);
+
+	return 0;
+}
+
 static const struct net_device_ops batadv_netdev_ops = {
+	.ndo_init = batadv_softif_init,
 	.ndo_open = batadv_interface_open,
 	.ndo_stop = batadv_interface_release,
 	.ndo_get_stats = batadv_interface_stats,
@@ -414,6 +481,9 @@ struct net_device *batadv_softif_create(const char *name)
 	atomic_set(&bat_priv->aggregated_ogms, 1);
 	atomic_set(&bat_priv->bonding, 0);
 	atomic_set(&bat_priv->bridge_loop_avoidance, 0);
+#ifdef CONFIG_BATMAN_ADV_DAT
+	atomic_set(&bat_priv->distributed_arp_table, 1);
+#endif
 	atomic_set(&bat_priv->ap_isolation, 0);
 	atomic_set(&bat_priv->vis_mode, BATADV_VIS_TYPE_CLIENT_UPDATE);
 	atomic_set(&bat_priv->gw_mode, BATADV_GW_MODE_OFF);
@@ -436,7 +506,6 @@ struct net_device *batadv_softif_create(const char *name)
 #endif
 	bat_priv->tt.last_changeset = NULL;
 	bat_priv->tt.last_changeset_len = 0;
-	bat_priv->tt.poss_change = false;
 
 	bat_priv->primary_if = NULL;
 	bat_priv->num_ifaces = 0;
@@ -556,6 +625,13 @@ static const struct {
 	{ "tt_response_rx" },
 	{ "tt_roam_adv_tx" },
 	{ "tt_roam_adv_rx" },
+#ifdef CONFIG_BATMAN_ADV_DAT
+	{ "dat_get_tx" },
+	{ "dat_get_rx" },
+	{ "dat_put_tx" },
+	{ "dat_put_rx" },
+	{ "dat_cached_reply_tx" },
+#endif
 };
 
 static void batadv_get_strings(struct net_device *dev, uint32_t stringset,
diff --git a/net/batman-adv/sysfs.c b/net/batman-adv/sysfs.c
index 66518c75c217..84a55cb19b0b 100644
--- a/net/batman-adv/sysfs.c
+++ b/net/batman-adv/sysfs.c
@@ -20,6 +20,7 @@
 #include "main.h"
 #include "sysfs.h"
 #include "translation-table.h"
+#include "distributed-arp-table.h"
 #include "originator.h"
 #include "hard-interface.h"
 #include "gateway_common.h"
@@ -122,55 +123,6 @@ ssize_t batadv_show_##_name(struct kobject *kobj,			\
 			   batadv_store_##_name)
 
 
-#define BATADV_ATTR_HIF_STORE_UINT(_name, _min, _max, _post_func)	\
-ssize_t batadv_store_##_name(struct kobject *kobj,			\
-			     struct attribute *attr, char *buff,	\
-			     size_t count)				\
-{									\
-	struct net_device *net_dev = batadv_kobj_to_netdev(kobj);	\
-	struct batadv_hard_iface *hard_iface;				\
-	ssize_t length;							\
-									\
-	hard_iface = batadv_hardif_get_by_netdev(net_dev);		\
-	if (!hard_iface)						\
-		return 0;						\
-									\
-	length = __batadv_store_uint_attr(buff, count, _min, _max,	\
-					  _post_func, attr,		\
-					  &hard_iface->_name, net_dev);	\
-									\
-	batadv_hardif_free_ref(hard_iface);				\
-	return length;							\
-}
-
-#define BATADV_ATTR_HIF_SHOW_UINT(_name)				\
-ssize_t batadv_show_##_name(struct kobject *kobj,			\
-			    struct attribute *attr, char *buff)		\
-{									\
-	struct net_device *net_dev = batadv_kobj_to_netdev(kobj);	\
-	struct batadv_hard_iface *hard_iface;				\
-	ssize_t length;							\
-									\
-	hard_iface = batadv_hardif_get_by_netdev(net_dev);		\
-	if (!hard_iface)						\
-		return 0;						\
-									\
-	length = sprintf(buff, "%i\n", atomic_read(&hard_iface->_name));\
-									\
-	batadv_hardif_free_ref(hard_iface);				\
-	return length;							\
-}
-
-/* Use this, if you are going to set [name] in hard_iface to an
- * unsigned integer value
- */
-#define BATADV_ATTR_HIF_UINT(_name, _mode, _min, _max, _post_func)	\
-	static BATADV_ATTR_HIF_STORE_UINT(_name, _min, _max, _post_func)\
-	static BATADV_ATTR_HIF_SHOW_UINT(_name)				\
-	static BATADV_ATTR(_name, _mode, batadv_show_##_name,		\
-			   batadv_store_##_name)
-
-
 static int batadv_store_bool_attr(char *buff, size_t count,
 				  struct net_device *net_dev,
 				  const char *attr_name, atomic_t *attr)
@@ -469,6 +421,9 @@ BATADV_ATTR_SIF_BOOL(bonding, S_IRUGO | S_IWUSR, NULL);
 #ifdef CONFIG_BATMAN_ADV_BLA
 BATADV_ATTR_SIF_BOOL(bridge_loop_avoidance, S_IRUGO | S_IWUSR, NULL);
 #endif
+#ifdef CONFIG_BATMAN_ADV_DAT
+BATADV_ATTR_SIF_BOOL(distributed_arp_table, S_IRUGO | S_IWUSR, NULL);
+#endif
 BATADV_ATTR_SIF_BOOL(fragmentation, S_IRUGO | S_IWUSR, batadv_update_min_mtu);
 BATADV_ATTR_SIF_BOOL(ap_isolation, S_IRUGO | S_IWUSR, NULL);
 static BATADV_ATTR(vis_mode, S_IRUGO | S_IWUSR, batadv_show_vis_mode,
@@ -494,6 +449,9 @@ static struct batadv_attribute *batadv_mesh_attrs[] = {
 #ifdef CONFIG_BATMAN_ADV_BLA
 	&batadv_attr_bridge_loop_avoidance,
 #endif
+#ifdef CONFIG_BATMAN_ADV_DAT
+	&batadv_attr_distributed_arp_table,
+#endif
 	&batadv_attr_fragmentation,
 	&batadv_attr_ap_isolation,
 	&batadv_attr_vis_mode,
@@ -730,7 +688,7 @@ int batadv_throw_uevent(struct batadv_priv *bat_priv, enum batadv_uev_type type,
 			enum batadv_uev_action action, const char *data)
 {
 	int ret = -ENOMEM;
-	struct batadv_hard_iface *primary_if = NULL;
+	struct batadv_hard_iface *primary_if;
 	struct kobject *bat_kobj;
 	char *uevent_env[4] = { NULL, NULL, NULL, NULL };
 
diff --git a/net/batman-adv/translation-table.c b/net/batman-adv/translation-table.c
index baae71585804..22457a7952ba 100644
--- a/net/batman-adv/translation-table.c
+++ b/net/batman-adv/translation-table.c
@@ -238,92 +238,134 @@ static int batadv_tt_local_init(struct batadv_priv *bat_priv)
 	return 0;
 }
 
+static void batadv_tt_global_free(struct batadv_priv *bat_priv,
+				  struct batadv_tt_global_entry *tt_global,
+				  const char *message)
+{
+	batadv_dbg(BATADV_DBG_TT, bat_priv,
+		   "Deleting global tt entry %pM: %s\n",
+		   tt_global->common.addr, message);
+
+	batadv_hash_remove(bat_priv->tt.global_hash, batadv_compare_tt,
+			   batadv_choose_orig, tt_global->common.addr);
+	batadv_tt_global_entry_free_ref(tt_global);
+
+}
+
 void batadv_tt_local_add(struct net_device *soft_iface, const uint8_t *addr,
 			 int ifindex)
 {
 	struct batadv_priv *bat_priv = netdev_priv(soft_iface);
-	struct batadv_tt_local_entry *tt_local_entry = NULL;
-	struct batadv_tt_global_entry *tt_global_entry = NULL;
+	struct batadv_tt_local_entry *tt_local;
+	struct batadv_tt_global_entry *tt_global;
 	struct hlist_head *head;
 	struct hlist_node *node;
 	struct batadv_tt_orig_list_entry *orig_entry;
 	int hash_added;
+	bool roamed_back = false;
 
-	tt_local_entry = batadv_tt_local_hash_find(bat_priv, addr);
+	tt_local = batadv_tt_local_hash_find(bat_priv, addr);
+	tt_global = batadv_tt_global_hash_find(bat_priv, addr);
 
-	if (tt_local_entry) {
-		tt_local_entry->last_seen = jiffies;
-		/* possibly unset the BATADV_TT_CLIENT_PENDING flag */
-		tt_local_entry->common.flags &= ~BATADV_TT_CLIENT_PENDING;
-		goto out;
+	if (tt_local) {
+		tt_local->last_seen = jiffies;
+		if (tt_local->common.flags & BATADV_TT_CLIENT_PENDING) {
+			batadv_dbg(BATADV_DBG_TT, bat_priv,
+				   "Re-adding pending client %pM\n", addr);
+			/* whatever the reason why the PENDING flag was set,
+			 * this is a client which was enqueued to be removed in
+			 * this orig_interval. Since it popped up again, the
+			 * flag can be reset like it was never enqueued
+			 */
+			tt_local->common.flags &= ~BATADV_TT_CLIENT_PENDING;
+			goto add_event;
+		}
+
+		if (tt_local->common.flags & BATADV_TT_CLIENT_ROAM) {
+			batadv_dbg(BATADV_DBG_TT, bat_priv,
+				   "Roaming client %pM came back to its original location\n",
+				   addr);
+			/* the ROAM flag is set because this client roamed away
+			 * and the node got a roaming_advertisement message. Now
+			 * that the client popped up again at its original
+			 * location such flag can be unset
+			 */
+			tt_local->common.flags &= ~BATADV_TT_CLIENT_ROAM;
+			roamed_back = true;
+		}
+		goto check_roaming;
 	}
 
-	tt_local_entry = kmalloc(sizeof(*tt_local_entry), GFP_ATOMIC);
-	if (!tt_local_entry)
+	tt_local = kmalloc(sizeof(*tt_local), GFP_ATOMIC);
+	if (!tt_local)
 		goto out;
 
 	batadv_dbg(BATADV_DBG_TT, bat_priv,
 		   "Creating new local tt entry: %pM (ttvn: %d)\n", addr,
 		   (uint8_t)atomic_read(&bat_priv->tt.vn));
 
-	memcpy(tt_local_entry->common.addr, addr, ETH_ALEN);
-	tt_local_entry->common.flags = BATADV_NO_FLAGS;
+	memcpy(tt_local->common.addr, addr, ETH_ALEN);
+	tt_local->common.flags = BATADV_NO_FLAGS;
 	if (batadv_is_wifi_iface(ifindex))
-		tt_local_entry->common.flags |= BATADV_TT_CLIENT_WIFI;
-	atomic_set(&tt_local_entry->common.refcount, 2);
-	tt_local_entry->last_seen = jiffies;
-	tt_local_entry->common.added_at = tt_local_entry->last_seen;
+		tt_local->common.flags |= BATADV_TT_CLIENT_WIFI;
+	atomic_set(&tt_local->common.refcount, 2);
+	tt_local->last_seen = jiffies;
+	tt_local->common.added_at = tt_local->last_seen;
 
 	/* the batman interface mac address should never be purged */
 	if (batadv_compare_eth(addr, soft_iface->dev_addr))
-		tt_local_entry->common.flags |= BATADV_TT_CLIENT_NOPURGE;
+		tt_local->common.flags |= BATADV_TT_CLIENT_NOPURGE;
 
 	/* The local entry has to be marked as NEW to avoid to send it in
 	 * a full table response going out before the next ttvn increment
 	 * (consistency check)
 	 */
-	tt_local_entry->common.flags |= BATADV_TT_CLIENT_NEW;
+	tt_local->common.flags |= BATADV_TT_CLIENT_NEW;
 
 	hash_added = batadv_hash_add(bat_priv->tt.local_hash, batadv_compare_tt,
-				     batadv_choose_orig,
-				     &tt_local_entry->common,
-				     &tt_local_entry->common.hash_entry);
+				     batadv_choose_orig, &tt_local->common,
+				     &tt_local->common.hash_entry);
 
 	if (unlikely(hash_added != 0)) {
 		/* remove the reference for the hash */
-		batadv_tt_local_entry_free_ref(tt_local_entry);
+		batadv_tt_local_entry_free_ref(tt_local);
 		goto out;
 	}
 
-	batadv_tt_local_event(bat_priv, addr, tt_local_entry->common.flags);
+add_event:
+	batadv_tt_local_event(bat_priv, addr, tt_local->common.flags);
 
-	/* remove address from global hash if present */
-	tt_global_entry = batadv_tt_global_hash_find(bat_priv, addr);
-
-	/* Check whether it is a roaming! */
-	if (tt_global_entry) {
+check_roaming:
+	/* Check whether it is a roaming, but don't do anything if the roaming
+	 * process has already been handled
+	 */
+	if (tt_global && !(tt_global->common.flags & BATADV_TT_CLIENT_ROAM)) {
 		/* These node are probably going to update their tt table */
-		head = &tt_global_entry->orig_list;
+		head = &tt_global->orig_list;
 		rcu_read_lock();
 		hlist_for_each_entry_rcu(orig_entry, node, head, list) {
-			orig_entry->orig_node->tt_poss_change = true;
-
-			batadv_send_roam_adv(bat_priv,
-					     tt_global_entry->common.addr,
+			batadv_send_roam_adv(bat_priv, tt_global->common.addr,
 					     orig_entry->orig_node);
 		}
 		rcu_read_unlock();
-		/* The global entry has to be marked as ROAMING and
-		 * has to be kept for consistency purpose
-		 */
-		tt_global_entry->common.flags |= BATADV_TT_CLIENT_ROAM;
-		tt_global_entry->roam_at = jiffies;
+		if (roamed_back) {
+			batadv_tt_global_free(bat_priv, tt_global,
+					      "Roaming canceled");
+			tt_global = NULL;
+		} else {
+			/* The global entry has to be marked as ROAMING and
+			 * has to be kept for consistency purpose
+			 */
+			tt_global->common.flags |= BATADV_TT_CLIENT_ROAM;
+			tt_global->roam_at = jiffies;
+		}
 	}
+
 out:
-	if (tt_local_entry)
-		batadv_tt_local_entry_free_ref(tt_local_entry);
-	if (tt_global_entry)
-		batadv_tt_global_entry_free_ref(tt_global_entry);
+	if (tt_local)
+		batadv_tt_local_entry_free_ref(tt_local);
+	if (tt_global)
+		batadv_tt_global_entry_free_ref(tt_global);
 }
 
 static void batadv_tt_realloc_packet_buff(unsigned char **packet_buff,
@@ -434,22 +476,10 @@ int batadv_tt_local_seq_print_text(struct seq_file *seq, void *offset)
 	struct hlist_node *node;
 	struct hlist_head *head;
 	uint32_t i;
-	int ret = 0;
 
-	primary_if = batadv_primary_if_get_selected(bat_priv);
-	if (!primary_if) {
-		ret = seq_printf(seq,
-				 "BATMAN mesh %s disabled - please specify interfaces to enable it\n",
-				 net_dev->name);
-		goto out;
-	}
-
-	if (primary_if->if_status != BATADV_IF_ACTIVE) {
-		ret = seq_printf(seq,
-				 "BATMAN mesh %s disabled - primary interface not active\n",
-				 net_dev->name);
+	primary_if = batadv_seq_print_text_primary_if_get(seq);
+	if (!primary_if)
 		goto out;
-	}
 
 	seq_printf(seq,
 		   "Locally retrieved addresses (from %s) announced via TT (TTVN: %u):\n",
@@ -479,7 +509,7 @@ int batadv_tt_local_seq_print_text(struct seq_file *seq, void *offset)
 out:
 	if (primary_if)
 		batadv_hardif_free_ref(primary_if);
-	return ret;
+	return 0;
 }
 
 static void
@@ -501,24 +531,57 @@ batadv_tt_local_set_pending(struct batadv_priv *bat_priv,
 		   tt_local_entry->common.addr, message);
 }
 
-void batadv_tt_local_remove(struct batadv_priv *bat_priv, const uint8_t *addr,
-			    const char *message, bool roaming)
+/**
+ * batadv_tt_local_remove - logically remove an entry from the local table
+ * @bat_priv: the bat priv with all the soft interface information
+ * @addr: the MAC address of the client to remove
+ * @message: message to append to the log on deletion
+ * @roaming: true if the deletion is due to a roaming event
+ *
+ * Returns the flags assigned to the local entry before being deleted
+ */
+uint16_t batadv_tt_local_remove(struct batadv_priv *bat_priv,
+				const uint8_t *addr, const char *message,
+				bool roaming)
 {
-	struct batadv_tt_local_entry *tt_local_entry = NULL;
-	uint16_t flags;
+	struct batadv_tt_local_entry *tt_local_entry;
+	uint16_t flags, curr_flags = BATADV_NO_FLAGS;
 
 	tt_local_entry = batadv_tt_local_hash_find(bat_priv, addr);
 	if (!tt_local_entry)
 		goto out;
 
+	curr_flags = tt_local_entry->common.flags;
+
 	flags = BATADV_TT_CLIENT_DEL;
-	if (roaming)
+	/* if this global entry addition is due to a roaming, the node has to
+	 * mark the local entry as "roamed" in order to correctly reroute
+	 * packets later
+	 */
+	if (roaming) {
 		flags |= BATADV_TT_CLIENT_ROAM;
+		/* mark the local client as ROAMed */
+		tt_local_entry->common.flags |= BATADV_TT_CLIENT_ROAM;
+	}
+
+	if (!(tt_local_entry->common.flags & BATADV_TT_CLIENT_NEW)) {
+		batadv_tt_local_set_pending(bat_priv, tt_local_entry, flags,
+					    message);
+		goto out;
+	}
+	/* if this client has been added right now, it is possible to
+	 * immediately purge it
+	 */
+	batadv_tt_local_event(bat_priv, tt_local_entry->common.addr,
+			      curr_flags | BATADV_TT_CLIENT_DEL);
+	hlist_del_rcu(&tt_local_entry->common.hash_entry);
+	batadv_tt_local_entry_free_ref(tt_local_entry);
 
-	batadv_tt_local_set_pending(bat_priv, tt_local_entry, flags, message);
 out:
 	if (tt_local_entry)
 		batadv_tt_local_entry_free_ref(tt_local_entry);
+
+	return curr_flags;
 }
 
 static void batadv_tt_local_purge_list(struct batadv_priv *bat_priv,
@@ -721,12 +784,23 @@ int batadv_tt_global_add(struct batadv_priv *bat_priv,
 			 const unsigned char *tt_addr, uint8_t flags,
 			 uint8_t ttvn)
 {
-	struct batadv_tt_global_entry *tt_global_entry = NULL;
+	struct batadv_tt_global_entry *tt_global_entry;
+	struct batadv_tt_local_entry *tt_local_entry;
 	int ret = 0;
 	int hash_added;
 	struct batadv_tt_common_entry *common;
+	uint16_t local_flags;
 
 	tt_global_entry = batadv_tt_global_hash_find(bat_priv, tt_addr);
+	tt_local_entry = batadv_tt_local_hash_find(bat_priv, tt_addr);
+
+	/* if the node already has a local client for this entry, it has to wait
+	 * for a roaming advertisement instead of manually messing up the global
+	 * table
+	 */
+	if ((flags & BATADV_TT_CLIENT_TEMP) && tt_local_entry &&
+	    !(tt_local_entry->common.flags & BATADV_TT_CLIENT_NEW))
+		goto out;
 
 	if (!tt_global_entry) {
 		tt_global_entry = kzalloc(sizeof(*tt_global_entry), GFP_ATOMIC);
@@ -738,6 +812,12 @@ int batadv_tt_global_add(struct batadv_priv *bat_priv,
 
 		common->flags = flags;
 		tt_global_entry->roam_at = 0;
+		/* node must store current time in case of roaming. This is
+		 * needed to purge this entry out on timeout (if nobody claims
+		 * it)
+		 */
+		if (flags & BATADV_TT_CLIENT_ROAM)
+			tt_global_entry->roam_at = jiffies;
 		atomic_set(&common->refcount, 2);
 		common->added_at = jiffies;
 
@@ -755,19 +835,31 @@ int batadv_tt_global_add(struct batadv_priv *bat_priv,
 			goto out_remove;
 		}
 	} else {
+		common = &tt_global_entry->common;
 		/* If there is already a global entry, we can use this one for
 		 * our processing.
-		 * But if we are trying to add a temporary client we can exit
-		 * directly because the temporary information should never
-		 * override any already known client state (whatever it is)
+		 * But if we are trying to add a temporary client then here are
+		 * two options at this point:
+		 * 1) the global client is not a temporary client: the global
+		 *    client has to be left as it is, temporary information
+		 *    should never override any already known client state
+		 * 2) the global client is a temporary client: purge the
+		 *    originator list and add the new one orig_entry
 		 */
-		if (flags & BATADV_TT_CLIENT_TEMP)
-			goto out;
+		if (flags & BATADV_TT_CLIENT_TEMP) {
+			if (!(common->flags & BATADV_TT_CLIENT_TEMP))
+				goto out;
+			if (batadv_tt_global_entry_has_orig(tt_global_entry,
+							    orig_node))
+				goto out_remove;
+			batadv_tt_global_del_orig_list(tt_global_entry);
+			goto add_orig_entry;
+		}
 
 		/* if the client was temporary added before receiving the first
 		 * OGM announcing it, we have to clear the TEMP flag
 		 */
-		tt_global_entry->common.flags &= ~BATADV_TT_CLIENT_TEMP;
+		common->flags &= ~BATADV_TT_CLIENT_TEMP;
 
 		/* the change can carry possible "attribute" flags like the
 		 * TT_CLIENT_WIFI, therefore they have to be copied in the
@@ -782,33 +874,81 @@ int batadv_tt_global_add(struct batadv_priv *bat_priv,
 		 * We should first delete the old originator before adding the
 		 * new one.
 		 */
-		if (tt_global_entry->common.flags & BATADV_TT_CLIENT_ROAM) {
+		if (common->flags & BATADV_TT_CLIENT_ROAM) {
 			batadv_tt_global_del_orig_list(tt_global_entry);
-			tt_global_entry->common.flags &= ~BATADV_TT_CLIENT_ROAM;
+			common->flags &= ~BATADV_TT_CLIENT_ROAM;
 			tt_global_entry->roam_at = 0;
 		}
 	}
+add_orig_entry:
 	/* add the new orig_entry (if needed) or update it */
 	batadv_tt_global_orig_entry_add(tt_global_entry, orig_node, ttvn);
 
 	batadv_dbg(BATADV_DBG_TT, bat_priv,
 		   "Creating new global tt entry: %pM (via %pM)\n",
-		   tt_global_entry->common.addr, orig_node->orig);
+		   common->addr, orig_node->orig);
+	ret = 1;
 
 out_remove:
+
 	/* remove address from local hash if present */
-	batadv_tt_local_remove(bat_priv, tt_global_entry->common.addr,
-			       "global tt received",
-			       flags & BATADV_TT_CLIENT_ROAM);
-	ret = 1;
+	local_flags = batadv_tt_local_remove(bat_priv, tt_addr,
+					     "global tt received",
+					     !!(flags & BATADV_TT_CLIENT_ROAM));
+	tt_global_entry->common.flags |= local_flags & BATADV_TT_CLIENT_WIFI;
+
+	if (!(flags & BATADV_TT_CLIENT_ROAM))
+		/* this is a normal global add. Therefore the client is not in a
+		 * roaming state anymore.
+		 */
+		tt_global_entry->common.flags &= ~BATADV_TT_CLIENT_ROAM;
+
 out:
 	if (tt_global_entry)
 		batadv_tt_global_entry_free_ref(tt_global_entry);
+	if (tt_local_entry)
+		batadv_tt_local_entry_free_ref(tt_local_entry);
 	return ret;
 }
 
-/* print all orig nodes who announce the address for this global entry.
- * it is assumed that the caller holds rcu_read_lock();
+/* batadv_transtable_best_orig - Get best originator list entry from tt entry
+ * @tt_global_entry: global translation table entry to be analyzed
+ *
+ * This functon assumes the caller holds rcu_read_lock().
+ * Returns best originator list entry or NULL on errors.
+ */
+static struct batadv_tt_orig_list_entry *
+batadv_transtable_best_orig(struct batadv_tt_global_entry *tt_global_entry)
+{
+	struct batadv_neigh_node *router = NULL;
+	struct hlist_head *head;
+	struct hlist_node *node;
+	struct batadv_tt_orig_list_entry *orig_entry, *best_entry = NULL;
+	int best_tq = 0;
+
+	head = &tt_global_entry->orig_list;
+	hlist_for_each_entry_rcu(orig_entry, node, head, list) {
+		router = batadv_orig_node_get_router(orig_entry->orig_node);
+		if (!router)
+			continue;
+
+		if (router->tq_avg > best_tq) {
+			best_entry = orig_entry;
+			best_tq = router->tq_avg;
+		}
+
+		batadv_neigh_node_free_ref(router);
+	}
+
+	return best_entry;
+}
+
+/* batadv_tt_global_print_entry - print all orig nodes who announce the address
+ * for this global entry
+ * @tt_global_entry: global translation table entry to be printed
+ * @seq: debugfs table seq_file struct
+ *
+ * This functon assumes the caller holds rcu_read_lock().
  */
 static void
 batadv_tt_global_print_entry(struct batadv_tt_global_entry *tt_global_entry,
@@ -816,21 +956,37 @@ batadv_tt_global_print_entry(struct batadv_tt_global_entry *tt_global_entry,
 {
 	struct hlist_head *head;
 	struct hlist_node *node;
-	struct batadv_tt_orig_list_entry *orig_entry;
+	struct batadv_tt_orig_list_entry *orig_entry, *best_entry;
 	struct batadv_tt_common_entry *tt_common_entry;
 	uint16_t flags;
 	uint8_t last_ttvn;
 
 	tt_common_entry = &tt_global_entry->common;
+	flags = tt_common_entry->flags;
+
+	best_entry = batadv_transtable_best_orig(tt_global_entry);
+	if (best_entry) {
+		last_ttvn = atomic_read(&best_entry->orig_node->last_ttvn);
+		seq_printf(seq,	" %c %pM  (%3u) via %pM     (%3u)   [%c%c%c]\n",
+			   '*', tt_global_entry->common.addr,
+			   best_entry->ttvn, best_entry->orig_node->orig,
+			   last_ttvn,
+			   (flags & BATADV_TT_CLIENT_ROAM ? 'R' : '.'),
+			   (flags & BATADV_TT_CLIENT_WIFI ? 'W' : '.'),
+			   (flags & BATADV_TT_CLIENT_TEMP ? 'T' : '.'));
+	}
 
 	head = &tt_global_entry->orig_list;
 
 	hlist_for_each_entry_rcu(orig_entry, node, head, list) {
-		flags = tt_common_entry->flags;
+		if (best_entry == orig_entry)
+			continue;
+
 		last_ttvn = atomic_read(&orig_entry->orig_node->last_ttvn);
-		seq_printf(seq,	" * %pM  (%3u) via %pM     (%3u)   [%c%c%c]\n",
-			   tt_global_entry->common.addr, orig_entry->ttvn,
-			   orig_entry->orig_node->orig, last_ttvn,
+		seq_printf(seq,	" %c %pM  (%3u) via %pM     (%3u)   [%c%c%c]\n",
+			   '+', tt_global_entry->common.addr,
+			   orig_entry->ttvn, orig_entry->orig_node->orig,
+			   last_ttvn,
 			   (flags & BATADV_TT_CLIENT_ROAM ? 'R' : '.'),
 			   (flags & BATADV_TT_CLIENT_WIFI ? 'W' : '.'),
 			   (flags & BATADV_TT_CLIENT_TEMP ? 'T' : '.'));
@@ -848,22 +1004,10 @@ int batadv_tt_global_seq_print_text(struct seq_file *seq, void *offset)
 	struct hlist_node *node;
 	struct hlist_head *head;
 	uint32_t i;
-	int ret = 0;
-
-	primary_if = batadv_primary_if_get_selected(bat_priv);
-	if (!primary_if) {
-		ret = seq_printf(seq,
-				 "BATMAN mesh %s disabled - please specify interfaces to enable it\n",
-				 net_dev->name);
-		goto out;
-	}
 
-	if (primary_if->if_status != BATADV_IF_ACTIVE) {
-		ret = seq_printf(seq,
-				 "BATMAN mesh %s disabled - primary interface not active\n",
-				 net_dev->name);
+	primary_if = batadv_seq_print_text_primary_if_get(seq);
+	if (!primary_if)
 		goto out;
-	}
 
 	seq_printf(seq,
 		   "Globally announced TT entries received via the mesh %s\n",
@@ -887,7 +1031,7 @@ int batadv_tt_global_seq_print_text(struct seq_file *seq, void *offset)
 out:
 	if (primary_if)
 		batadv_hardif_free_ref(primary_if);
-	return ret;
+	return 0;
 }
 
 /* deletes the orig list of a tt_global_entry */
@@ -933,21 +1077,6 @@ batadv_tt_global_del_orig_entry(struct batadv_priv *bat_priv,
 	spin_unlock_bh(&tt_global_entry->list_lock);
 }
 
-static void
-batadv_tt_global_del_struct(struct batadv_priv *bat_priv,
-			    struct batadv_tt_global_entry *tt_global_entry,
-			    const char *message)
-{
-	batadv_dbg(BATADV_DBG_TT, bat_priv,
-		   "Deleting global tt entry %pM: %s\n",
-		   tt_global_entry->common.addr, message);
-
-	batadv_hash_remove(bat_priv->tt.global_hash, batadv_compare_tt,
-			   batadv_choose_orig, tt_global_entry->common.addr);
-	batadv_tt_global_entry_free_ref(tt_global_entry);
-
-}
-
 /* If the client is to be deleted, we check if it is the last origantor entry
  * within tt_global entry. If yes, we set the BATADV_TT_CLIENT_ROAM flag and the
  * timer, otherwise we simply remove the originator scheduled for deletion.
@@ -996,7 +1125,7 @@ static void batadv_tt_global_del(struct batadv_priv *bat_priv,
 				 const unsigned char *addr,
 				 const char *message, bool roaming)
 {
-	struct batadv_tt_global_entry *tt_global_entry = NULL;
+	struct batadv_tt_global_entry *tt_global_entry;
 	struct batadv_tt_local_entry *local_entry = NULL;
 
 	tt_global_entry = batadv_tt_global_hash_find(bat_priv, addr);
@@ -1008,8 +1137,8 @@ static void batadv_tt_global_del(struct batadv_priv *bat_priv,
 						orig_node, message);
 
 		if (hlist_empty(&tt_global_entry->orig_list))
-			batadv_tt_global_del_struct(bat_priv, tt_global_entry,
-						    message);
+			batadv_tt_global_free(bat_priv, tt_global_entry,
+					      message);
 
 		goto out;
 	}
@@ -1032,7 +1161,7 @@ static void batadv_tt_global_del(struct batadv_priv *bat_priv,
 	if (local_entry) {
 		/* local entry exists, case 2: client roamed to us. */
 		batadv_tt_global_del_orig_list(tt_global_entry);
-		batadv_tt_global_del_struct(bat_priv, tt_global_entry, message);
+		batadv_tt_global_free(bat_priv, tt_global_entry, message);
 	} else
 		/* no local entry exists, case 1: check for roaming */
 		batadv_tt_global_del_roaming(bat_priv, tt_global_entry,
@@ -1203,15 +1332,12 @@ struct batadv_orig_node *batadv_transtable_search(struct batadv_priv *bat_priv,
 	struct batadv_tt_local_entry *tt_local_entry = NULL;
 	struct batadv_tt_global_entry *tt_global_entry = NULL;
 	struct batadv_orig_node *orig_node = NULL;
-	struct batadv_neigh_node *router = NULL;
-	struct hlist_head *head;
-	struct hlist_node *node;
-	struct batadv_tt_orig_list_entry *orig_entry;
-	int best_tq;
+	struct batadv_tt_orig_list_entry *best_entry;
 
 	if (src && atomic_read(&bat_priv->ap_isolation)) {
 		tt_local_entry = batadv_tt_local_hash_find(bat_priv, src);
-		if (!tt_local_entry)
+		if (!tt_local_entry ||
+		    (tt_local_entry->common.flags & BATADV_TT_CLIENT_PENDING))
 			goto out;
 	}
 
@@ -1226,25 +1352,15 @@ struct batadv_orig_node *batadv_transtable_search(struct batadv_priv *bat_priv,
 	    _batadv_is_ap_isolated(tt_local_entry, tt_global_entry))
 		goto out;
 
-	best_tq = 0;
-
 	rcu_read_lock();
-	head = &tt_global_entry->orig_list;
-	hlist_for_each_entry_rcu(orig_entry, node, head, list) {
-		router = batadv_orig_node_get_router(orig_entry->orig_node);
-		if (!router)
-			continue;
-
-		if (router->tq_avg > best_tq) {
-			orig_node = orig_entry->orig_node;
-			best_tq = router->tq_avg;
-		}
-		batadv_neigh_node_free_ref(router);
-	}
+	best_entry = batadv_transtable_best_orig(tt_global_entry);
 	/* found anything? */
+	if (best_entry)
+		orig_node = best_entry->orig_node;
 	if (orig_node && !atomic_inc_not_zero(&orig_node->refcount))
 		orig_node = NULL;
 	rcu_read_unlock();
+
 out:
 	if (tt_global_entry)
 		batadv_tt_global_entry_free_ref(tt_global_entry);
@@ -1477,11 +1593,11 @@ batadv_tt_response_fill_table(uint16_t tt_len, uint8_t ttvn,
 	tt_tot = tt_len / sizeof(struct batadv_tt_change);
 
 	len = tt_query_size + tt_len;
-	skb = dev_alloc_skb(len + ETH_HLEN);
+	skb = dev_alloc_skb(len + ETH_HLEN + NET_IP_ALIGN);
 	if (!skb)
 		goto out;
 
-	skb_reserve(skb, ETH_HLEN);
+	skb_reserve(skb, ETH_HLEN + NET_IP_ALIGN);
 	tt_response = (struct batadv_tt_query_packet *)skb_put(skb, len);
 	tt_response->ttvn = ttvn;
 
@@ -1526,7 +1642,6 @@ static int batadv_send_tt_request(struct batadv_priv *bat_priv,
 {
 	struct sk_buff *skb = NULL;
 	struct batadv_tt_query_packet *tt_request;
-	struct batadv_neigh_node *neigh_node = NULL;
 	struct batadv_hard_iface *primary_if;
 	struct batadv_tt_req_node *tt_req_node = NULL;
 	int ret = 1;
@@ -1543,11 +1658,11 @@ static int batadv_send_tt_request(struct batadv_priv *bat_priv,
 	if (!tt_req_node)
 		goto out;
 
-	skb = dev_alloc_skb(sizeof(*tt_request) + ETH_HLEN);
+	skb = dev_alloc_skb(sizeof(*tt_request) + ETH_HLEN + NET_IP_ALIGN);
 	if (!skb)
 		goto out;
 
-	skb_reserve(skb, ETH_HLEN);
+	skb_reserve(skb, ETH_HLEN + NET_IP_ALIGN);
 
 	tt_req_len = sizeof(*tt_request);
 	tt_request = (struct batadv_tt_query_packet *)skb_put(skb, tt_req_len);
@@ -1564,23 +1679,15 @@ static int batadv_send_tt_request(struct batadv_priv *bat_priv,
 	if (full_table)
 		tt_request->flags |= BATADV_TT_FULL_TABLE;
 
-	neigh_node = batadv_orig_node_get_router(dst_orig_node);
-	if (!neigh_node)
-		goto out;
-
-	batadv_dbg(BATADV_DBG_TT, bat_priv,
-		   "Sending TT_REQUEST to %pM via %pM [%c]\n",
-		   dst_orig_node->orig, neigh_node->addr,
-		   (full_table ? 'F' : '.'));
+	batadv_dbg(BATADV_DBG_TT, bat_priv, "Sending TT_REQUEST to %pM [%c]\n",
+		   dst_orig_node->orig, (full_table ? 'F' : '.'));
 
 	batadv_inc_counter(bat_priv, BATADV_CNT_TT_REQUEST_TX);
 
-	batadv_send_skb_packet(skb, neigh_node->if_incoming, neigh_node->addr);
-	ret = 0;
+	if (batadv_send_skb_to_orig(skb, dst_orig_node, NULL))
+		ret = 0;
 
 out:
-	if (neigh_node)
-		batadv_neigh_node_free_ref(neigh_node);
 	if (primary_if)
 		batadv_hardif_free_ref(primary_if);
 	if (ret)
@@ -1598,9 +1705,8 @@ static bool
 batadv_send_other_tt_response(struct batadv_priv *bat_priv,
 			      struct batadv_tt_query_packet *tt_request)
 {
-	struct batadv_orig_node *req_dst_orig_node = NULL;
+	struct batadv_orig_node *req_dst_orig_node;
 	struct batadv_orig_node *res_dst_orig_node = NULL;
-	struct batadv_neigh_node *neigh_node = NULL;
 	struct batadv_hard_iface *primary_if = NULL;
 	uint8_t orig_ttvn, req_ttvn, ttvn;
 	int ret = false;
@@ -1626,10 +1732,6 @@ batadv_send_other_tt_response(struct batadv_priv *bat_priv,
 	if (!res_dst_orig_node)
 		goto out;
 
-	neigh_node = batadv_orig_node_get_router(res_dst_orig_node);
-	if (!neigh_node)
-		goto out;
-
 	primary_if = batadv_primary_if_get_selected(bat_priv);
 	if (!primary_if)
 		goto out;
@@ -1658,11 +1760,11 @@ batadv_send_other_tt_response(struct batadv_priv *bat_priv,
 		tt_tot = tt_len / sizeof(struct batadv_tt_change);
 
 		len = sizeof(*tt_response) + tt_len;
-		skb = dev_alloc_skb(len + ETH_HLEN);
+		skb = dev_alloc_skb(len + ETH_HLEN + NET_IP_ALIGN);
 		if (!skb)
 			goto unlock;
 
-		skb_reserve(skb, ETH_HLEN);
+		skb_reserve(skb, ETH_HLEN + NET_IP_ALIGN);
 		packet_pos = skb_put(skb, len);
 		tt_response = (struct batadv_tt_query_packet *)packet_pos;
 		tt_response->ttvn = req_ttvn;
@@ -1701,14 +1803,13 @@ batadv_send_other_tt_response(struct batadv_priv *bat_priv,
 		tt_response->flags |= BATADV_TT_FULL_TABLE;
 
 	batadv_dbg(BATADV_DBG_TT, bat_priv,
-		   "Sending TT_RESPONSE %pM via %pM for %pM (ttvn: %u)\n",
-		   res_dst_orig_node->orig, neigh_node->addr,
-		   req_dst_orig_node->orig, req_ttvn);
+		   "Sending TT_RESPONSE %pM for %pM (ttvn: %u)\n",
+		   res_dst_orig_node->orig, req_dst_orig_node->orig, req_ttvn);
 
 	batadv_inc_counter(bat_priv, BATADV_CNT_TT_RESPONSE_TX);
 
-	batadv_send_skb_packet(skb, neigh_node->if_incoming, neigh_node->addr);
-	ret = true;
+	if (batadv_send_skb_to_orig(skb, res_dst_orig_node, NULL))
+		ret = true;
 	goto out;
 
 unlock:
@@ -1719,8 +1820,6 @@ out:
 		batadv_orig_node_free_ref(res_dst_orig_node);
 	if (req_dst_orig_node)
 		batadv_orig_node_free_ref(req_dst_orig_node);
-	if (neigh_node)
-		batadv_neigh_node_free_ref(neigh_node);
 	if (primary_if)
 		batadv_hardif_free_ref(primary_if);
 	if (!ret)
@@ -1733,8 +1832,7 @@ static bool
 batadv_send_my_tt_response(struct batadv_priv *bat_priv,
 			   struct batadv_tt_query_packet *tt_request)
 {
-	struct batadv_orig_node *orig_node = NULL;
-	struct batadv_neigh_node *neigh_node = NULL;
+	struct batadv_orig_node *orig_node;
 	struct batadv_hard_iface *primary_if = NULL;
 	uint8_t my_ttvn, req_ttvn, ttvn;
 	int ret = false;
@@ -1759,10 +1857,6 @@ batadv_send_my_tt_response(struct batadv_priv *bat_priv,
 	if (!orig_node)
 		goto out;
 
-	neigh_node = batadv_orig_node_get_router(orig_node);
-	if (!neigh_node)
-		goto out;
-
 	primary_if = batadv_primary_if_get_selected(bat_priv);
 	if (!primary_if)
 		goto out;
@@ -1785,11 +1879,11 @@ batadv_send_my_tt_response(struct batadv_priv *bat_priv,
 		tt_tot = tt_len / sizeof(struct batadv_tt_change);
 
 		len = sizeof(*tt_response) + tt_len;
-		skb = dev_alloc_skb(len + ETH_HLEN);
+		skb = dev_alloc_skb(len + ETH_HLEN + NET_IP_ALIGN);
 		if (!skb)
 			goto unlock;
 
-		skb_reserve(skb, ETH_HLEN);
+		skb_reserve(skb, ETH_HLEN + NET_IP_ALIGN);
 		packet_pos = skb_put(skb, len);
 		tt_response = (struct batadv_tt_query_packet *)packet_pos;
 		tt_response->ttvn = req_ttvn;
@@ -1826,14 +1920,14 @@ batadv_send_my_tt_response(struct batadv_priv *bat_priv,
 		tt_response->flags |= BATADV_TT_FULL_TABLE;
 
 	batadv_dbg(BATADV_DBG_TT, bat_priv,
-		   "Sending TT_RESPONSE to %pM via %pM [%c]\n",
-		   orig_node->orig, neigh_node->addr,
+		   "Sending TT_RESPONSE to %pM [%c]\n",
+		   orig_node->orig,
 		   (tt_response->flags & BATADV_TT_FULL_TABLE ? 'F' : '.'));
 
 	batadv_inc_counter(bat_priv, BATADV_CNT_TT_RESPONSE_TX);
 
-	batadv_send_skb_packet(skb, neigh_node->if_incoming, neigh_node->addr);
-	ret = true;
+	if (batadv_send_skb_to_orig(skb, orig_node, NULL))
+		ret = true;
 	goto out;
 
 unlock:
@@ -1841,8 +1935,6 @@ unlock:
 out:
 	if (orig_node)
 		batadv_orig_node_free_ref(orig_node);
-	if (neigh_node)
-		batadv_neigh_node_free_ref(neigh_node);
 	if (primary_if)
 		batadv_hardif_free_ref(primary_if);
 	if (!ret)
@@ -1899,7 +1991,7 @@ static void _batadv_tt_update_changes(struct batadv_priv *bat_priv,
 static void batadv_tt_fill_gtable(struct batadv_priv *bat_priv,
 				  struct batadv_tt_query_packet *tt_response)
 {
-	struct batadv_orig_node *orig_node = NULL;
+	struct batadv_orig_node *orig_node;
 
 	orig_node = batadv_orig_hash_find(bat_priv, tt_response->src);
 	if (!orig_node)
@@ -1941,7 +2033,7 @@ static void batadv_tt_update_changes(struct batadv_priv *bat_priv,
 
 bool batadv_is_my_client(struct batadv_priv *bat_priv, const uint8_t *addr)
 {
-	struct batadv_tt_local_entry *tt_local_entry = NULL;
+	struct batadv_tt_local_entry *tt_local_entry;
 	bool ret = false;
 
 	tt_local_entry = batadv_tt_local_hash_find(bat_priv, addr);
@@ -1950,7 +2042,8 @@ bool batadv_is_my_client(struct batadv_priv *bat_priv, const uint8_t *addr)
 	/* Check if the client has been logically deleted (but is kept for
 	 * consistency purpose)
 	 */
-	if (tt_local_entry->common.flags & BATADV_TT_CLIENT_PENDING)
+	if ((tt_local_entry->common.flags & BATADV_TT_CLIENT_PENDING) ||
+	    (tt_local_entry->common.flags & BATADV_TT_CLIENT_ROAM))
 		goto out;
 	ret = true;
 out:
@@ -2001,10 +2094,6 @@ void batadv_handle_tt_response(struct batadv_priv *bat_priv,
 
 	/* Recalculate the CRC for this orig_node and store it */
 	orig_node->tt_crc = batadv_tt_global_crc(bat_priv, orig_node);
-	/* Roaming phase is over: tables are in sync again. I can
-	 * unset the flag
-	 */
-	orig_node->tt_poss_change = false;
 out:
 	if (orig_node)
 		batadv_orig_node_free_ref(orig_node);
@@ -2110,7 +2199,6 @@ unlock:
 static void batadv_send_roam_adv(struct batadv_priv *bat_priv, uint8_t *client,
 				 struct batadv_orig_node *orig_node)
 {
-	struct batadv_neigh_node *neigh_node = NULL;
 	struct sk_buff *skb = NULL;
 	struct batadv_roam_adv_packet *roam_adv_packet;
 	int ret = 1;
@@ -2123,11 +2211,11 @@ static void batadv_send_roam_adv(struct batadv_priv *bat_priv, uint8_t *client,
 	if (!batadv_tt_check_roam_count(bat_priv, client))
 		goto out;
 
-	skb = dev_alloc_skb(sizeof(*roam_adv_packet) + ETH_HLEN);
+	skb = dev_alloc_skb(sizeof(*roam_adv_packet) + ETH_HLEN + NET_IP_ALIGN);
 	if (!skb)
 		goto out;
 
-	skb_reserve(skb, ETH_HLEN);
+	skb_reserve(skb, ETH_HLEN + NET_IP_ALIGN);
 
 	roam_adv_packet = (struct batadv_roam_adv_packet *)skb_put(skb, len);
 
@@ -2143,23 +2231,17 @@ static void batadv_send_roam_adv(struct batadv_priv *bat_priv, uint8_t *client,
 	memcpy(roam_adv_packet->dst, orig_node->orig, ETH_ALEN);
 	memcpy(roam_adv_packet->client, client, ETH_ALEN);
 
-	neigh_node = batadv_orig_node_get_router(orig_node);
-	if (!neigh_node)
-		goto out;
-
 	batadv_dbg(BATADV_DBG_TT, bat_priv,
-		   "Sending ROAMING_ADV to %pM (client %pM) via %pM\n",
-		   orig_node->orig, client, neigh_node->addr);
+		   "Sending ROAMING_ADV to %pM (client %pM)\n",
+		   orig_node->orig, client);
 
 	batadv_inc_counter(bat_priv, BATADV_CNT_TT_ROAM_ADV_TX);
 
-	batadv_send_skb_packet(skb, neigh_node->if_incoming, neigh_node->addr);
-	ret = 0;
+	if (batadv_send_skb_to_orig(skb, orig_node, NULL))
+		ret = 0;
 
 out:
-	if (neigh_node)
-		batadv_neigh_node_free_ref(neigh_node);
-	if (ret)
+	if (ret && skb)
 		kfree_skb(skb);
 	return;
 }
@@ -2295,7 +2377,6 @@ static int batadv_tt_commit_changes(struct batadv_priv *bat_priv,
 	batadv_dbg(BATADV_DBG_TT, bat_priv,
 		   "Local changes committed, updating to ttvn %u\n",
 		   (uint8_t)atomic_read(&bat_priv->tt.vn));
-	bat_priv->tt.poss_change = false;
 
 	/* reset the sending counter */
 	atomic_set(&bat_priv->tt.ogm_append_cnt, BATADV_TT_OGM_APPEND_MAX);
@@ -2407,11 +2488,6 @@ void batadv_tt_update_orig(struct batadv_priv *bat_priv,
 		 */
 		if (orig_node->tt_crc != tt_crc)
 			goto request_table;
-
-		/* Roaming phase is over: tables are in sync again. I can
-		 * unset the flag
-		 */
-		orig_node->tt_poss_change = false;
 	} else {
 		/* if we missed more than one change or our tables are not
 		 * in sync anymore -> request fresh tt data
@@ -2444,12 +2520,38 @@ bool batadv_tt_global_client_is_roaming(struct batadv_priv *bat_priv,
 	if (!tt_global_entry)
 		goto out;
 
-	ret = tt_global_entry->common.flags & BATADV_TT_CLIENT_ROAM;
+	ret = !!(tt_global_entry->common.flags & BATADV_TT_CLIENT_ROAM);
 	batadv_tt_global_entry_free_ref(tt_global_entry);
 out:
 	return ret;
 }
 
+/**
+ * batadv_tt_local_client_is_roaming - tells whether the client is roaming
+ * @bat_priv: the bat priv with all the soft interface information
+ * @addr: the MAC address of the local client to query
+ *
+ * Returns true if the local client is known to be roaming (it is not served by
+ * this node anymore) or not. If yes, the client is still present in the table
+ * to keep the latter consistent with the node TTVN
+ */
+bool batadv_tt_local_client_is_roaming(struct batadv_priv *bat_priv,
+				       uint8_t *addr)
+{
+	struct batadv_tt_local_entry *tt_local_entry;
+	bool ret = false;
+
+	tt_local_entry = batadv_tt_local_hash_find(bat_priv, addr);
+	if (!tt_local_entry)
+		goto out;
+
+	ret = tt_local_entry->common.flags & BATADV_TT_CLIENT_ROAM;
+	batadv_tt_local_entry_free_ref(tt_local_entry);
+out:
+	return ret;
+
+}
+
 bool batadv_tt_add_temporary_global_entry(struct batadv_priv *bat_priv,
 					  struct batadv_orig_node *orig_node,
 					  const unsigned char *addr)
diff --git a/net/batman-adv/translation-table.h b/net/batman-adv/translation-table.h
index 811fffd4760c..46d4451a59ee 100644
--- a/net/batman-adv/translation-table.h
+++ b/net/batman-adv/translation-table.h
@@ -24,9 +24,9 @@ int batadv_tt_len(int changes_num);
 int batadv_tt_init(struct batadv_priv *bat_priv);
 void batadv_tt_local_add(struct net_device *soft_iface, const uint8_t *addr,
 			 int ifindex);
-void batadv_tt_local_remove(struct batadv_priv *bat_priv,
-			    const uint8_t *addr, const char *message,
-			    bool roaming);
+uint16_t batadv_tt_local_remove(struct batadv_priv *bat_priv,
+				const uint8_t *addr, const char *message,
+				bool roaming);
 int batadv_tt_local_seq_print_text(struct seq_file *seq, void *offset);
 void batadv_tt_global_add_orig(struct batadv_priv *bat_priv,
 			       struct batadv_orig_node *orig_node,
@@ -59,6 +59,8 @@ int batadv_tt_append_diff(struct batadv_priv *bat_priv,
 			  int packet_min_len);
 bool batadv_tt_global_client_is_roaming(struct batadv_priv *bat_priv,
 					uint8_t *addr);
+bool batadv_tt_local_client_is_roaming(struct batadv_priv *bat_priv,
+				       uint8_t *addr);
 bool batadv_tt_add_temporary_global_entry(struct batadv_priv *bat_priv,
 					  struct batadv_orig_node *orig_node,
 					  const unsigned char *addr);
diff --git a/net/batman-adv/types.h b/net/batman-adv/types.h
index ac1e07a80454..ae9ac9aca8c5 100644
--- a/net/batman-adv/types.h
+++ b/net/batman-adv/types.h
@@ -28,20 +28,41 @@
 	(ETH_HLEN + max(sizeof(struct batadv_unicast_packet), \
 			sizeof(struct batadv_bcast_packet)))
 
+#ifdef CONFIG_BATMAN_ADV_DAT
+
+/* batadv_dat_addr_t is the type used for all DHT addresses. If it is changed,
+ * BATADV_DAT_ADDR_MAX is changed as well.
+ *
+ * *Please be careful: batadv_dat_addr_t must be UNSIGNED*
+ */
+#define batadv_dat_addr_t uint16_t
+
+#endif /* CONFIG_BATMAN_ADV_DAT */
+
+/**
+ * struct batadv_hard_iface_bat_iv - per hard interface B.A.T.M.A.N. IV data
+ * @ogm_buff: buffer holding the OGM packet
+ * @ogm_buff_len: length of the OGM packet buffer
+ * @ogm_seqno: OGM sequence number - used to identify each OGM
+ */
+struct batadv_hard_iface_bat_iv {
+	unsigned char *ogm_buff;
+	int ogm_buff_len;
+	atomic_t ogm_seqno;
+};
+
 struct batadv_hard_iface {
 	struct list_head list;
 	int16_t if_num;
 	char if_status;
 	struct net_device *net_dev;
-	atomic_t seqno;
 	atomic_t frag_seqno;
-	unsigned char *packet_buff;
-	int packet_len;
 	struct kobject *hardif_obj;
 	atomic_t refcount;
 	struct packet_type batman_adv_ptype;
 	struct net_device *soft_iface;
 	struct rcu_head rcu;
+	struct batadv_hard_iface_bat_iv bat_iv;
 };
 
 /**
@@ -63,6 +84,9 @@ struct batadv_orig_node {
 	uint8_t orig[ETH_ALEN];
 	uint8_t primary_addr[ETH_ALEN];
 	struct batadv_neigh_node __rcu *router; /* rcu protected pointer */
+#ifdef CONFIG_BATMAN_ADV_DAT
+	batadv_dat_addr_t dat_addr;
+#endif
 	unsigned long *bcast_own;
 	uint8_t *bcast_own_sum;
 	unsigned long last_seen;
@@ -77,13 +101,6 @@ struct batadv_orig_node {
 	spinlock_t tt_buff_lock; /* protects tt_buff */
 	atomic_t tt_size;
 	bool tt_initialised;
-	/* The tt_poss_change flag is used to detect an ongoing roaming phase.
-	 * If true, then I sent a Roaming_adv to this orig_node and I have to
-	 * inspect every packet directed to it to check whether it is still
-	 * the true destination or not. This flag will be reset to false as
-	 * soon as I receive a new TTVN from this orig_node
-	 */
-	bool tt_poss_change;
 	uint32_t last_real_seqno;
 	uint8_t last_ttl;
 	DECLARE_BITMAP(bcast_bits, BATADV_TQ_LOCAL_WINDOW_SIZE);
@@ -139,7 +156,7 @@ struct batadv_neigh_node {
 #ifdef CONFIG_BATMAN_ADV_BLA
 struct batadv_bcast_duplist_entry {
 	uint8_t orig[ETH_ALEN];
-	uint16_t crc;
+	__be32 crc;
 	unsigned long entrytime;
 };
 #endif
@@ -162,6 +179,13 @@ enum batadv_counters {
 	BATADV_CNT_TT_RESPONSE_RX,
 	BATADV_CNT_TT_ROAM_ADV_TX,
 	BATADV_CNT_TT_ROAM_ADV_RX,
+#ifdef CONFIG_BATMAN_ADV_DAT
+	BATADV_CNT_DAT_GET_TX,
+	BATADV_CNT_DAT_GET_RX,
+	BATADV_CNT_DAT_PUT_TX,
+	BATADV_CNT_DAT_PUT_RX,
+	BATADV_CNT_DAT_CACHED_REPLY_TX,
+#endif
 	BATADV_CNT_NUM,
 };
 
@@ -181,7 +205,6 @@ struct batadv_priv_tt {
 	atomic_t vn;
 	atomic_t ogm_append_cnt;
 	atomic_t local_changes;
-	bool poss_change;
 	struct list_head changes_list;
 	struct batadv_hashtable *local_hash;
 	struct batadv_hashtable *global_hash;
@@ -228,6 +251,20 @@ struct batadv_priv_vis {
 	struct batadv_vis_info *my_info;
 };
 
+/**
+ * struct batadv_priv_dat - per mesh interface DAT private data
+ * @addr: node DAT address
+ * @hash: hashtable representing the local ARP cache
+ * @work: work queue callback item for cache purging
+ */
+#ifdef CONFIG_BATMAN_ADV_DAT
+struct batadv_priv_dat {
+	batadv_dat_addr_t addr;
+	struct batadv_hashtable *hash;
+	struct delayed_work work;
+};
+#endif
+
 struct batadv_priv {
 	atomic_t mesh_state;
 	struct net_device_stats stats;
@@ -237,6 +274,9 @@ struct batadv_priv {
 	atomic_t fragmentation;		/* boolean */
 	atomic_t ap_isolation;		/* boolean */
 	atomic_t bridge_loop_avoidance;	/* boolean */
+#ifdef CONFIG_BATMAN_ADV_DAT
+	atomic_t distributed_arp_table;	/* boolean */
+#endif
 	atomic_t vis_mode;		/* VIS_TYPE_* */
 	atomic_t gw_mode;		/* GW_MODE_* */
 	atomic_t gw_sel_class;		/* uint */
@@ -255,7 +295,7 @@ struct batadv_priv {
 	struct hlist_head forw_bcast_list;
 	struct batadv_hashtable *orig_hash;
 	spinlock_t forw_bat_list_lock; /* protects forw_bat_list */
-	spinlock_t forw_bcast_list_lock; /* protects  */
+	spinlock_t forw_bcast_list_lock; /* protects forw_bcast_list */
 	struct delayed_work orig_work;
 	struct batadv_hard_iface __rcu *primary_if;  /* rcu protected pointer */
 	struct batadv_algo_ops *bat_algo_ops;
@@ -265,6 +305,9 @@ struct batadv_priv {
 	struct batadv_priv_gw gw;
 	struct batadv_priv_tt tt;
 	struct batadv_priv_vis vis;
+#ifdef CONFIG_BATMAN_ADV_DAT
+	struct batadv_priv_dat dat;
+#endif
 };
 
 struct batadv_socket_client {
@@ -318,6 +361,7 @@ struct batadv_backbone_gw {
 	struct hlist_node hash_entry;
 	struct batadv_priv *bat_priv;
 	unsigned long lasttime;	/* last time we heard of this backbone gw */
+	atomic_t wait_periods;
 	atomic_t request_sent;
 	atomic_t refcount;
 	struct rcu_head rcu;
@@ -437,4 +481,36 @@ struct batadv_algo_ops {
 	void (*bat_ogm_emit)(struct batadv_forw_packet *forw_packet);
 };
 
+/**
+ * struct batadv_dat_entry - it is a single entry of batman-adv ARP backend. It
+ * is used to stored ARP entries needed for the global DAT cache
+ * @ip: the IPv4 corresponding to this DAT/ARP entry
+ * @mac_addr: the MAC address associated to the stored IPv4
+ * @last_update: time in jiffies when this entry was refreshed last time
+ * @hash_entry: hlist node for batadv_priv_dat::hash
+ * @refcount: number of contexts the object is used
+ * @rcu: struct used for freeing in an RCU-safe manner
+ */
+struct batadv_dat_entry {
+	__be32 ip;
+	uint8_t mac_addr[ETH_ALEN];
+	unsigned long last_update;
+	struct hlist_node hash_entry;
+	atomic_t refcount;
+	struct rcu_head rcu;
+};
+
+/**
+ * struct batadv_dat_candidate - candidate destination for DAT operations
+ * @type: the type of the selected candidate. It can one of the following:
+ *	  - BATADV_DAT_CANDIDATE_NOT_FOUND
+ *	  - BATADV_DAT_CANDIDATE_ORIG
+ * @orig_node: if type is BATADV_DAT_CANDIDATE_ORIG this field points to the
+ *	       corresponding originator node structure
+ */
+struct batadv_dat_candidate {
+	int type;
+	struct batadv_orig_node *orig_node;
+};
+
 #endif /* _NET_BATMAN_ADV_TYPES_H_ */
diff --git a/net/batman-adv/unicast.c b/net/batman-adv/unicast.c
index f39723281ca1..10aff49fcf25 100644
--- a/net/batman-adv/unicast.c
+++ b/net/batman-adv/unicast.c
@@ -291,14 +291,118 @@ out:
 	return ret;
 }
 
-int batadv_unicast_send_skb(struct sk_buff *skb, struct batadv_priv *bat_priv)
+/**
+ * batadv_unicast_push_and_fill_skb - extends the buffer and initializes the
+ * common fields for unicast packets
+ * @skb: packet
+ * @hdr_size: amount of bytes to push at the beginning of the skb
+ * @orig_node: the destination node
+ *
+ * Returns false if the buffer extension was not possible or true otherwise
+ */
+static bool batadv_unicast_push_and_fill_skb(struct sk_buff *skb, int hdr_size,
+					     struct batadv_orig_node *orig_node)
+{
+	struct batadv_unicast_packet *unicast_packet;
+	uint8_t ttvn = (uint8_t)atomic_read(&orig_node->last_ttvn);
+
+	if (batadv_skb_head_push(skb, hdr_size) < 0)
+		return false;
+
+	unicast_packet = (struct batadv_unicast_packet *)skb->data;
+	unicast_packet->header.version = BATADV_COMPAT_VERSION;
+	/* batman packet type: unicast */
+	unicast_packet->header.packet_type = BATADV_UNICAST;
+	/* set unicast ttl */
+	unicast_packet->header.ttl = BATADV_TTL;
+	/* copy the destination for faster routing */
+	memcpy(unicast_packet->dest, orig_node->orig, ETH_ALEN);
+	/* set the destination tt version number */
+	unicast_packet->ttvn = ttvn;
+
+	return true;
+}
+
+/**
+ * batadv_unicast_prepare_skb - encapsulate an skb with a unicast header
+ * @skb: the skb containing the payload to encapsulate
+ * @orig_node: the destination node
+ *
+ * Returns false if the payload could not be encapsulated or true otherwise
+ */
+static bool batadv_unicast_prepare_skb(struct sk_buff *skb,
+				       struct batadv_orig_node *orig_node)
+{
+	size_t uni_size = sizeof(struct batadv_unicast_packet);
+	return batadv_unicast_push_and_fill_skb(skb, uni_size, orig_node);
+}
+
+/**
+ * batadv_unicast_4addr_prepare_skb - encapsulate an skb with a unicast4addr
+ * header
+ * @bat_priv: the bat priv with all the soft interface information
+ * @skb: the skb containing the payload to encapsulate
+ * @orig_node: the destination node
+ * @packet_subtype: the batman 4addr packet subtype to use
+ *
+ * Returns false if the payload could not be encapsulated or true otherwise
+ */
+bool batadv_unicast_4addr_prepare_skb(struct batadv_priv *bat_priv,
+				      struct sk_buff *skb,
+				      struct batadv_orig_node *orig,
+				      int packet_subtype)
+{
+	struct batadv_hard_iface *primary_if;
+	struct batadv_unicast_4addr_packet *unicast_4addr_packet;
+	bool ret = false;
+
+	primary_if = batadv_primary_if_get_selected(bat_priv);
+	if (!primary_if)
+		goto out;
+
+	/* pull the header space and fill the unicast_packet substructure.
+	 * We can do that because the first member of the unicast_4addr_packet
+	 * is of type struct unicast_packet
+	 */
+	if (!batadv_unicast_push_and_fill_skb(skb,
+					      sizeof(*unicast_4addr_packet),
+					      orig))
+		goto out;
+
+	unicast_4addr_packet = (struct batadv_unicast_4addr_packet *)skb->data;
+	unicast_4addr_packet->u.header.packet_type = BATADV_UNICAST_4ADDR;
+	memcpy(unicast_4addr_packet->src, primary_if->net_dev->dev_addr,
+	       ETH_ALEN);
+	unicast_4addr_packet->subtype = packet_subtype;
+	unicast_4addr_packet->reserved = 0;
+
+	ret = true;
+out:
+	if (primary_if)
+		batadv_hardif_free_ref(primary_if);
+	return ret;
+}
+
+/**
+ * batadv_unicast_generic_send_skb - send an skb as unicast
+ * @bat_priv: the bat priv with all the soft interface information
+ * @skb: payload to send
+ * @packet_type: the batman unicast packet type to use
+ * @packet_subtype: the batman packet subtype. It is ignored if packet_type is
+ *		    not BATADV_UNICAT_4ADDR
+ *
+ * Returns 1 in case of error or 0 otherwise
+ */
+int batadv_unicast_generic_send_skb(struct batadv_priv *bat_priv,
+				    struct sk_buff *skb, int packet_type,
+				    int packet_subtype)
 {
 	struct ethhdr *ethhdr = (struct ethhdr *)skb->data;
 	struct batadv_unicast_packet *unicast_packet;
 	struct batadv_orig_node *orig_node;
 	struct batadv_neigh_node *neigh_node;
 	int data_len = skb->len;
-	int ret = 1;
+	int ret = NET_RX_DROP;
 	unsigned int dev_mtu;
 
 	/* get routing information */
@@ -324,21 +428,23 @@ find_router:
 	if (!neigh_node)
 		goto out;
 
-	if (batadv_skb_head_push(skb, sizeof(*unicast_packet)) < 0)
+	switch (packet_type) {
+	case BATADV_UNICAST:
+		batadv_unicast_prepare_skb(skb, orig_node);
+		break;
+	case BATADV_UNICAST_4ADDR:
+		batadv_unicast_4addr_prepare_skb(bat_priv, skb, orig_node,
+						 packet_subtype);
+		break;
+	default:
+		/* this function supports UNICAST and UNICAST_4ADDR only. It
+		 * should never be invoked with any other packet type
+		 */
 		goto out;
+	}
 
 	unicast_packet = (struct batadv_unicast_packet *)skb->data;
 
-	unicast_packet->header.version = BATADV_COMPAT_VERSION;
-	/* batman packet type: unicast */
-	unicast_packet->header.packet_type = BATADV_UNICAST;
-	/* set unicast ttl */
-	unicast_packet->header.ttl = BATADV_TTL;
-	/* copy the destination for faster routing */
-	memcpy(unicast_packet->dest, orig_node->orig, ETH_ALEN);
-	/* set the destination tt version number */
-	unicast_packet->ttvn = (uint8_t)atomic_read(&orig_node->last_ttvn);
-
 	/* inform the destination node that we are still missing a correct route
 	 * for this client. The destination will receive this packet and will
 	 * try to reroute it because the ttvn contained in the header is less
@@ -348,7 +454,9 @@ find_router:
 		unicast_packet->ttvn = unicast_packet->ttvn - 1;
 
 	dev_mtu = neigh_node->if_incoming->net_dev->mtu;
-	if (atomic_read(&bat_priv->fragmentation) &&
+	/* fragmentation mechanism only works for UNICAST (now) */
+	if (packet_type == BATADV_UNICAST &&
+	    atomic_read(&bat_priv->fragmentation) &&
 	    data_len + sizeof(*unicast_packet) > dev_mtu) {
 		/* send frag skb decreases ttl */
 		unicast_packet->header.ttl++;
@@ -358,16 +466,15 @@ find_router:
 		goto out;
 	}
 
-	batadv_send_skb_packet(skb, neigh_node->if_incoming, neigh_node->addr);
-	ret = 0;
-	goto out;
+	if (batadv_send_skb_to_orig(skb, orig_node, NULL))
+		ret = 0;
 
 out:
 	if (neigh_node)
 		batadv_neigh_node_free_ref(neigh_node);
 	if (orig_node)
 		batadv_orig_node_free_ref(orig_node);
-	if (ret == 1)
+	if (ret == NET_RX_DROP)
 		kfree_skb(skb);
 	return ret;
 }
diff --git a/net/batman-adv/unicast.h b/net/batman-adv/unicast.h
index 1c46e2eb1ef9..61abba58bd8f 100644
--- a/net/batman-adv/unicast.h
+++ b/net/batman-adv/unicast.h
@@ -29,10 +29,44 @@ int batadv_frag_reassemble_skb(struct sk_buff *skb,
 			       struct batadv_priv *bat_priv,
 			       struct sk_buff **new_skb);
 void batadv_frag_list_free(struct list_head *head);
-int batadv_unicast_send_skb(struct sk_buff *skb, struct batadv_priv *bat_priv);
 int batadv_frag_send_skb(struct sk_buff *skb, struct batadv_priv *bat_priv,
 			 struct batadv_hard_iface *hard_iface,
 			 const uint8_t dstaddr[]);
+bool batadv_unicast_4addr_prepare_skb(struct batadv_priv *bat_priv,
+				      struct sk_buff *skb,
+				      struct batadv_orig_node *orig_node,
+				      int packet_subtype);
+int batadv_unicast_generic_send_skb(struct batadv_priv *bat_priv,
+				    struct sk_buff *skb, int packet_type,
+				    int packet_subtype);
+
+
+/**
+ * batadv_unicast_send_skb - send the skb encapsulated in a unicast packet
+ * @bat_priv: the bat priv with all the soft interface information
+ * @skb: the payload to send
+ */
+static inline int batadv_unicast_send_skb(struct batadv_priv *bat_priv,
+					  struct sk_buff *skb)
+{
+	return batadv_unicast_generic_send_skb(bat_priv, skb, BATADV_UNICAST,
+					       0);
+}
+
+/**
+ * batadv_unicast_send_skb - send the skb encapsulated in a unicast4addr packet
+ * @bat_priv: the bat priv with all the soft interface information
+ * @skb: the payload to send
+ * @packet_subtype: the batman 4addr packet subtype to use
+ */
+static inline int batadv_unicast_4addr_send_skb(struct batadv_priv *bat_priv,
+						struct sk_buff *skb,
+						int packet_subtype)
+{
+	return batadv_unicast_generic_send_skb(bat_priv, skb,
+					       BATADV_UNICAST_4ADDR,
+					       packet_subtype);
+}
 
 static inline int batadv_frag_can_reassemble(const struct sk_buff *skb, int mtu)
 {
diff --git a/net/batman-adv/vis.c b/net/batman-adv/vis.c
index 5abd1454fb07..0f65a9de5f74 100644
--- a/net/batman-adv/vis.c
+++ b/net/batman-adv/vis.c
@@ -396,12 +396,12 @@ batadv_add_packet(struct batadv_priv *bat_priv,
 		return NULL;
 
 	len = sizeof(*packet) + vis_info_len;
-	info->skb_packet = dev_alloc_skb(len + ETH_HLEN);
+	info->skb_packet = dev_alloc_skb(len + ETH_HLEN + NET_IP_ALIGN);
 	if (!info->skb_packet) {
 		kfree(info);
 		return NULL;
 	}
-	skb_reserve(info->skb_packet, ETH_HLEN);
+	skb_reserve(info->skb_packet, ETH_HLEN + NET_IP_ALIGN);
 	packet = (struct batadv_vis_packet *)skb_put(info->skb_packet, len);
 
 	kref_init(&info->refcount);
@@ -698,15 +698,12 @@ static void batadv_purge_vis_packets(struct batadv_priv *bat_priv)
 static void batadv_broadcast_vis_packet(struct batadv_priv *bat_priv,
 					struct batadv_vis_info *info)
 {
-	struct batadv_neigh_node *router;
 	struct batadv_hashtable *hash = bat_priv->orig_hash;
 	struct hlist_node *node;
 	struct hlist_head *head;
 	struct batadv_orig_node *orig_node;
 	struct batadv_vis_packet *packet;
 	struct sk_buff *skb;
-	struct batadv_hard_iface *hard_iface;
-	uint8_t dstaddr[ETH_ALEN];
 	uint32_t i;
 
 
@@ -722,30 +719,20 @@ static void batadv_broadcast_vis_packet(struct batadv_priv *bat_priv,
 			if (!(orig_node->flags & BATADV_VIS_SERVER))
 				continue;
 
-			router = batadv_orig_node_get_router(orig_node);
-			if (!router)
-				continue;
-
 			/* don't send it if we already received the packet from
 			 * this node.
 			 */
 			if (batadv_recv_list_is_in(bat_priv, &info->recv_list,
-						   orig_node->orig)) {
-				batadv_neigh_node_free_ref(router);
+						   orig_node->orig))
 				continue;
-			}
 
 			memcpy(packet->target_orig, orig_node->orig, ETH_ALEN);
-			hard_iface = router->if_incoming;
-			memcpy(dstaddr, router->addr, ETH_ALEN);
-
-			batadv_neigh_node_free_ref(router);
-
 			skb = skb_clone(info->skb_packet, GFP_ATOMIC);
-			if (skb)
-				batadv_send_skb_packet(skb, hard_iface,
-						       dstaddr);
+			if (!skb)
+				continue;
 
+			if (!batadv_send_skb_to_orig(skb, orig_node, NULL))
+				kfree_skb(skb);
 		}
 		rcu_read_unlock();
 	}
@@ -755,7 +742,6 @@ static void batadv_unicast_vis_packet(struct batadv_priv *bat_priv,
 				      struct batadv_vis_info *info)
 {
 	struct batadv_orig_node *orig_node;
-	struct batadv_neigh_node *router = NULL;
 	struct sk_buff *skb;
 	struct batadv_vis_packet *packet;
 
@@ -765,17 +751,14 @@ static void batadv_unicast_vis_packet(struct batadv_priv *bat_priv,
 	if (!orig_node)
 		goto out;
 
-	router = batadv_orig_node_get_router(orig_node);
-	if (!router)
+	skb = skb_clone(info->skb_packet, GFP_ATOMIC);
+	if (!skb)
 		goto out;
 
-	skb = skb_clone(info->skb_packet, GFP_ATOMIC);
-	if (skb)
-		batadv_send_skb_packet(skb, router->if_incoming, router->addr);
+	if (!batadv_send_skb_to_orig(skb, orig_node, NULL))
+		kfree_skb(skb);
 
 out:
-	if (router)
-		batadv_neigh_node_free_ref(router);
 	if (orig_node)
 		batadv_orig_node_free_ref(orig_node);
 }
@@ -873,12 +856,13 @@ int batadv_vis_init(struct batadv_priv *bat_priv)
 	if (!bat_priv->vis.my_info)
 		goto err;
 
-	len = sizeof(*packet) + BATADV_MAX_VIS_PACKET_SIZE + ETH_HLEN;
+	len = sizeof(*packet) + BATADV_MAX_VIS_PACKET_SIZE;
+	len += ETH_HLEN + NET_IP_ALIGN;
 	bat_priv->vis.my_info->skb_packet = dev_alloc_skb(len);
 	if (!bat_priv->vis.my_info->skb_packet)
 		goto free_info;
 
-	skb_reserve(bat_priv->vis.my_info->skb_packet, ETH_HLEN);
+	skb_reserve(bat_priv->vis.my_info->skb_packet, ETH_HLEN + NET_IP_ALIGN);
 	tmp_skb = bat_priv->vis.my_info->skb_packet;
 	packet = (struct batadv_vis_packet *)skb_put(tmp_skb, sizeof(*packet));