CATWOMAN: Network coding in batman-adv

index 21fe698..bbb91a5 100644
@@ -35,6 +35,7 @@
 #include "vis.h"
 #include "hash.h"
 #include "bat_algo.h"
+#include "network-coding.h"
 
 
 /* List manipulations on hardif_list have to be rtnl_lock()'ed,

@@ -135,6 +136,10 @@ int batadv_mesh_init(struct net_device *soft_iface)
 	if (ret < 0)
 		goto err;
 
+	ret = batadv_nc_init(bat_priv);
+	if (ret < 0)
+		goto err;
+
 	atomic_set(&bat_priv->gw.reselect, 0);
 	atomic_set(&bat_priv->mesh_state, BATADV_MESH_ACTIVE);
 

@@ -157,6 +162,7 @@ void batadv_mesh_free(struct net_device *soft_iface)
 
 	batadv_gw_node_purge(bat_priv);
 	batadv_originator_free(bat_priv);
+	batadv_nc_free(bat_priv);
 
 	batadv_tt_free(bat_priv);
 

index 08c5dd1..bf70aed 100644
@@ -187,6 +187,7 @@ __be32 batadv_skb_crc32(struct sk_buff *skb, u8 *payload_ptr);
  * @BATADV_DBG_TT: translation table messages
  * @BATADV_DBG_BLA: bridge loop avoidance messages
  * @BATADV_DBG_DAT: ARP snooping and DAT related messages
+ * @BATADV_DBG_NC: network coding related messages
  * @BATADV_DBG_ALL: the union of all the above log levels
  */
 enum batadv_dbg_level {

@@ -195,7 +196,8 @@ enum batadv_dbg_level {
 	BATADV_DBG_TT	  = BIT(2),
 	BATADV_DBG_BLA    = BIT(3),
 	BATADV_DBG_DAT    = BIT(4),
-	BATADV_DBG_ALL    = 31,
+	BATADV_DBG_NC	  = BIT(5),
+	BATADV_DBG_ALL    = 63,
 };
 
 #ifdef CONFIG_BATMAN_ADV_DEBUG

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index 2711e87..7188e07 100644
@@ -37,6 +37,7 @@
 #include <linux/if_ether.h>
 #include "unicast.h"
 #include "bridge_loop_avoidance.h"
+#include "network-coding.h"
 
 
 static int batadv_get_settings(struct net_device *dev, struct ethtool_cmd *cmd);

@@ -544,6 +545,8 @@ struct net_device *batadv_softif_create(const char *name)
 	if (ret < 0)
 		goto unreg_soft_iface;
 
+	batadv_nc_init_bat_priv(bat_priv);
+
 	ret = batadv_sysfs_add_meshif(soft_iface);
 	if (ret < 0)
 		goto unreg_soft_iface;

index afbba31..334bca9 100644
@@ -442,6 +442,9 @@ static BATADV_ATTR(gw_bandwidth, S_IRUGO | S_IWUSR, batadv_show_gw_bwidth,
 #ifdef CONFIG_BATMAN_ADV_DEBUG
 BATADV_ATTR_SIF_UINT(log_level, S_IRUGO | S_IWUSR, 0, BATADV_DBG_ALL, NULL);
 #endif
+#ifdef CONFIG_BATMAN_ADV_NC
+BATADV_ATTR_SIF_BOOL(network_coding, S_IRUGO | S_IWUSR, NULL);
+#endif
 
 static struct batadv_attribute *batadv_mesh_attrs[] = {
 	&batadv_attr_aggregated_ogms,

@@ -464,6 +467,9 @@ static struct batadv_attribute *batadv_mesh_attrs[] = {
 #ifdef CONFIG_BATMAN_ADV_DEBUG
 	&batadv_attr_log_level,
 #endif
+#ifdef CONFIG_BATMAN_ADV_NC
+	&batadv_attr_network_coding,
+#endif
 	NULL,
 };
 

index 4cd87a0..20de752 100644
@@ -428,6 +428,14 @@ struct batadv_priv_dat {
 #endif
 
 /**
+ * struct batadv_priv_nc - per mesh interface network coding private data
+ * @work: work queue callback item for cleanup
+ */
+struct batadv_priv_nc {
+	struct delayed_work work;
+};
+
+/**
  * struct batadv_priv - per mesh interface data
  * @mesh_state: current status of the mesh (inactive/active/deactivating)
  * @soft_iface: net device which holds this struct as private data

@@ -470,6 +478,8 @@ struct batadv_priv_dat {
  * @tt: translation table data
  * @vis: vis data
  * @dat: distributed arp table data
+ * @network_coding: enable/disable network coding
+ * @batadv_priv_nc: network coding private data
  */
 struct batadv_priv {
 	atomic_t mesh_state;

@@ -522,6 +532,10 @@ struct batadv_priv {
 #ifdef CONFIG_BATMAN_ADV_DAT
 	struct batadv_priv_dat dat;
 #endif
+#ifdef CONFIG_BATMAN_ADV_NC
+	atomic_t network_coding; /* boolean */
+	struct batadv_priv_nc nc;
+#endif /* CONFIG_BATMAN_ADV_NC */
 };
 
 /**

index 72fe1bb..7654b76 100644
@@ -27,6 +27,7 @@
 #include "hard-interface.h"
 #include "send.h"
 #include "bat_algo.h"
+#include "network-coding.h"
 
 static struct batadv_neigh_node *
 batadv_iv_ogm_neigh_new(struct batadv_hard_iface *hard_iface,

@@ -1189,6 +1190,10 @@ static void batadv_iv_ogm_process(const struct ethhdr *ethhdr,
 	if (!orig_neigh_node)
 		goto out;
 
+	/* Update nc_nodes of the originator */
+	batadv_nc_update_nc_node(bat_priv, orig_node, orig_neigh_node,
+				 batadv_ogm_packet, is_single_hop_neigh);
+
 	orig_neigh_router = batadv_orig_node_get_router(orig_neigh_node);
 
 	/* drop packet if sender is not a direct neighbor and if we

index 6ae8651..f186a55 100644
@@ -32,6 +32,7 @@
 #include "icmp_socket.h"
 #include "bridge_loop_avoidance.h"
 #include "distributed-arp-table.h"
+#include "network-coding.h"
 
 static struct dentry *batadv_debugfs;
 

@@ -310,6 +311,14 @@ struct batadv_debuginfo {
 	const struct file_operations fops;
 };
 
+#ifdef CONFIG_BATMAN_ADV_NC
+static int batadv_nc_nodes_open(struct inode *inode, struct file *file)
+{
+	struct net_device *net_dev = (struct net_device *)inode->i_private;
+	return single_open(file, batadv_nc_nodes_seq_print_text, net_dev);
+}
+#endif
+
 #define BATADV_DEBUGINFO(_name, _mode, _open)		\
 struct batadv_debuginfo batadv_debuginfo_##_name = {	\
 	.attr = { .name = __stringify(_name),		\

@@ -348,6 +357,9 @@ static BATADV_DEBUGINFO(dat_cache, S_IRUGO, batadv_dat_cache_open);
 static BATADV_DEBUGINFO(transtable_local, S_IRUGO,
 			batadv_transtable_local_open);
 static BATADV_DEBUGINFO(vis_data, S_IRUGO, batadv_vis_data_open);
+#ifdef CONFIG_BATMAN_ADV_NC
+static BATADV_DEBUGINFO(nc_nodes, S_IRUGO, batadv_nc_nodes_open);
+#endif
 
 static struct batadv_debuginfo *batadv_mesh_debuginfos[] = {
 	&batadv_debuginfo_originators,

@@ -362,6 +374,9 @@ static struct batadv_debuginfo *batadv_mesh_debuginfos[] = {
 #endif
 	&batadv_debuginfo_transtable_local,
 	&batadv_debuginfo_vis_data,
+#ifdef CONFIG_BATMAN_ADV_NC
+	&batadv_debuginfo_nc_nodes,
+#endif
 	NULL,
 };
 

@@ -431,6 +446,9 @@ int batadv_debugfs_add_meshif(struct net_device *dev)
 		}
 	}
 
+	if (batadv_nc_init_debugfs(bat_priv) < 0)
+		goto rem_attr;
+
 	return 0;
 rem_attr:
 	debugfs_remove_recursive(bat_priv->debug_dir);

index bf70aed..4e81d93 100644
@@ -105,6 +105,8 @@
 #define BATADV_RESET_PROTECTION_MS 30000
 #define BATADV_EXPECTED_SEQNO_RANGE	65536
 
+#define BATADV_NC_NODE_TIMEOUT 10000 /* Milliseconds */
+
 enum batadv_mesh_state {
 	BATADV_MESH_INACTIVE,
 	BATADV_MESH_ACTIVE,

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index 457ea44..9bedd50 100644
@@ -28,6 +28,7 @@
 #include "unicast.h"
 #include "soft-interface.h"
 #include "bridge_loop_avoidance.h"
+#include "network-coding.h"
 
 /* hash class keys */
 static struct lock_class_key batadv_orig_hash_lock_class_key;

@@ -142,6 +143,9 @@ static void batadv_orig_node_free_rcu(struct rcu_head *rcu)
 
 	spin_unlock_bh(&orig_node->neigh_list_lock);
 
+	/* Free nc_nodes */
+	batadv_nc_purge_orig(orig_node->bat_priv, orig_node, NULL);
+
 	batadv_frag_list_free(&orig_node->frag_list);
 	batadv_tt_global_del_orig(orig_node->bat_priv, orig_node,
 				  "originator timed out");

@@ -219,6 +223,8 @@ struct batadv_orig_node *batadv_get_orig_node(struct batadv_priv *bat_priv,
 	spin_lock_init(&orig_node->neigh_list_lock);
 	spin_lock_init(&orig_node->tt_buff_lock);
 
+	batadv_nc_init_orig(orig_node);
+
 	/* extra reference for return */
 	atomic_set(&orig_node->refcount, 2);
 

index 20de752..f759f33 100644
@@ -128,6 +128,10 @@ struct batadv_hard_iface {
  * @bond_list: list of bonding candidates
  * @refcount: number of contexts the object is used
  * @rcu: struct used for freeing in an RCU-safe manner
+ * @in_coding_list: list of nodes this orig can hear
+ * @out_coding_list: list of nodes that can hear this orig
+ * @in_coding_list_lock: protects in_coding_list
+ * @out_coding_list_lock: protects out_coding_list
  */
 struct batadv_orig_node {
 	uint8_t orig[ETH_ALEN];

@@ -171,6 +175,12 @@ struct batadv_orig_node {
 	struct list_head bond_list;
 	atomic_t refcount;
 	struct rcu_head rcu;
+#ifdef CONFIG_BATMAN_ADV_NC
+	struct list_head in_coding_list;
+	struct list_head out_coding_list;
+	spinlock_t in_coding_list_lock; /* Protects in_coding_list */
+	spinlock_t out_coding_list_lock; /* Protects out_coding_list */
+#endif
 };
 
 /**

@@ -430,9 +440,13 @@ struct batadv_priv_dat {
 /**
  * struct batadv_priv_nc - per mesh interface network coding private data
  * @work: work queue callback item for cleanup
+ * @debug_dir: dentry for nc subdir in batman-adv directory in debugfs
+ * @min_tq: only consider neighbors for encoding if neigh_tq > min_tq
  */
 struct batadv_priv_nc {
 	struct delayed_work work;
+	struct dentry *debug_dir;
+	u8 min_tq;
 };
 
 /**

@@ -716,6 +730,24 @@ struct batadv_tt_roam_node {
 };
 
 /**
+ * struct batadv_nc_node - network coding node
+ * @list: next and prev pointer for the list handling
+ * @addr: the node's mac address
+ * @refcount: number of contexts the object is used by
+ * @rcu: struct used for freeing in an RCU-safe manner
+ * @orig_node: pointer to corresponding orig node struct
+ * @last_seen: timestamp of last ogm received from this node
+ */
+struct batadv_nc_node {
+	struct list_head list;
+	uint8_t addr[ETH_ALEN];
+	atomic_t refcount;
+	struct rcu_head rcu;
+	struct batadv_orig_node *orig_node;
+	unsigned long last_seen;
+};
+
+/**
  * struct batadv_forw_packet - structure for bcast packets to be sent/forwarded
  * @list: list node for batadv_socket_client::queue_list
  * @send_time: execution time for delayed_work (packet sending)

index 6c8fec8..764878f 100644
@@ -74,4 +74,14 @@ void batadv_free_rcu_dat_entry(struct rcu_head *rcu)
 }
 #endif
 
+#ifdef CONFIG_BATMAN_ADV_NC
+void batadv_free_rcu_nc_path(struct rcu_head *rcu)
+{
+	struct batadv_nc_path *nc_path;
+
+	nc_path = container_of(rcu, struct batadv_nc_path, rcu);
+	kfree(nc_path);
+}
+#endif
+
 #endif /* < KERNEL_VERSION(3, 0, 0) */

index e21b310..48180e2 100644
@@ -145,6 +145,7 @@ void batadv_free_rcu_neigh_node(struct rcu_head *rcu);
 void batadv_free_rcu_tt_local_entry(struct rcu_head *rcu);
 void batadv_free_rcu_backbone_gw(struct rcu_head *rcu);
 void batadv_free_rcu_dat_entry(struct rcu_head *rcu);
+void batadv_free_rcu_nc_path(struct rcu_head *rcu);
 
 static inline void skb_reset_mac_len(struct sk_buff *skb)
 {

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index 55e5a7b..6e53cc8 100644
@@ -35,6 +35,9 @@ void batadv_nc_purge_orig(struct batadv_priv *bat_priv,
 					   struct batadv_nc_node *));
 void batadv_nc_init_bat_priv(struct batadv_priv *bat_priv);
 void batadv_nc_init_orig(struct batadv_orig_node *orig_node);
+bool batadv_nc_skb_forward(struct sk_buff *skb,
+			   struct batadv_neigh_node *neigh_node,
+			   struct ethhdr *ethhdr);
 int batadv_nc_nodes_seq_print_text(struct seq_file *seq, void *offset);
 int batadv_nc_init_debugfs(struct batadv_priv *bat_priv);
 

@@ -79,6 +82,13 @@ static inline void batadv_nc_init_orig(struct batadv_orig_node *orig_node)
 	return;
 }
 
+static inline bool batadv_nc_skb_forward(struct sk_buff *skb,
+					 struct batadv_neigh_node *neigh_node,
+					 struct ethhdr *ethhdr)
+{
+	return false;
+}
+
 static inline int batadv_nc_nodes_seq_print_text(struct seq_file *seq,
 						 void *offset)
 {

index 60ba03f..2765fc3 100644
@@ -29,6 +29,7 @@
 #include "unicast.h"
 #include "bridge_loop_avoidance.h"
 #include "distributed-arp-table.h"
+#include "network-coding.h"
 
 static int batadv_route_unicast_packet(struct sk_buff *skb,
 				       struct batadv_hard_iface *recv_if);

@@ -852,14 +853,17 @@ static int batadv_route_unicast_packet(struct sk_buff *skb,
 	/* decrement ttl */
 	unicast_packet->header.ttl--;
 
-	/* Update stats counter */
-	batadv_inc_counter(bat_priv, BATADV_CNT_FORWARD);
-	batadv_add_counter(bat_priv, BATADV_CNT_FORWARD_BYTES,
-			   skb->len + ETH_HLEN);
-
-	/* route it */
-	if (batadv_send_skb_to_orig(skb, orig_node, recv_if))
+	/* network code packet if possible */
+	if (batadv_nc_skb_forward(skb, neigh_node, ethhdr)) {
 		ret = NET_RX_SUCCESS;
+	} else if (batadv_send_skb_to_orig(skb, orig_node, recv_if)) {
+		ret = NET_RX_SUCCESS;
+
+		/* Update stats counter */
+		batadv_inc_counter(bat_priv, BATADV_CNT_FORWARD);
+		batadv_add_counter(bat_priv, BATADV_CNT_FORWARD_BYTES,
+				   skb->len + ETH_HLEN);
+	}
 
 out:
 	if (neigh_node)

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index 4e81d93..8a9caa0 100644
@@ -304,4 +304,10 @@ static inline uint64_t batadv_sum_counter(struct batadv_priv *bat_priv,
 	return sum;
 }
 
+/* Define a macro to reach the control buffer of the skb. The members of the
+ * control buffer are defined in struct batadv_skb_cb in types.h.
+ * The macro is inspired by the similar macro TCP_SKB_CB() in tcp.h.
+ */
+#define BATADV_SKB_CB(__skb)       ((struct batadv_skb_cb *)&((__skb)->cb[0]))
+
 #endif /* _NET_BATMAN_ADV_MAIN_H_ */

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index ed0aa89..a079958 100644
@@ -30,6 +30,7 @@ enum batadv_packettype {
 	BATADV_TT_QUERY		= 0x07,
 	BATADV_ROAM_ADV		= 0x08,
 	BATADV_UNICAST_4ADDR	= 0x09,
+	BATADV_CODED		= 0x0a,
 };
 
 /**

@@ -278,4 +279,36 @@ struct batadv_tt_change {
 	uint8_t addr[ETH_ALEN];
 } __packed;
 
+/**
+ * struct batadv_coded_packet - network coded packet
+ * @header: common batman packet header and ttl of first included packet
+ * @reserved: Align following fields to 2-byte boundaries
+ * @first_source: original source of first included packet
+ * @first_orig_dest: original destinal of first included packet
+ * @first_crc: checksum of first included packet
+ * @first_ttvn: tt-version number of first included packet
+ * @second_ttl: ttl of second packet
+ * @second_dest: second receiver of this coded packet
+ * @second_source: original source of second included packet
+ * @second_orig_dest: original destination of second included packet
+ * @second_crc: checksum of second included packet
+ * @second_ttvn: tt version number of second included packet
+ * @coded_len: length of network coded part of the payload
+ */
+struct batadv_coded_packet {
+	struct batadv_header header;
+	uint8_t  first_ttvn;
+	/* uint8_t  first_dest[ETH_ALEN]; - saved in mac header destination */
+	uint8_t  first_source[ETH_ALEN];
+	uint8_t  first_orig_dest[ETH_ALEN];
+	__be32   first_crc;
+	uint8_t  second_ttl;
+	uint8_t  second_ttvn;
+	uint8_t  second_dest[ETH_ALEN];
+	uint8_t  second_source[ETH_ALEN];
+	uint8_t  second_orig_dest[ETH_ALEN];
+	__be32   second_crc;
+	uint16_t coded_len;
+};
+
 #endif /* _NET_BATMAN_ADV_PACKET_H_ */

index 7188e07..7e463c3 100644
@@ -665,6 +665,12 @@ static const struct {
 	{ "dat_put_rx" },
 	{ "dat_cached_reply_tx" },
 #endif
+#ifdef CONFIG_BATMAN_ADV_NC
+	{ "nc_code" },
+	{ "nc_code_bytes" },
+	{ "nc_recode" },
+	{ "nc_recode_bytes" },
+#endif
 };
 
 static void batadv_get_strings(struct net_device *dev, uint32_t stringset,

index 6f19d08..8d72160 100644
@@ -275,6 +275,10 @@ struct batadv_bcast_duplist_entry {
  * @BATADV_CNT_DAT_PUT_RX: received dht PUT traffic packet counter
  * @BATADV_CNT_DAT_CACHED_REPLY_TX: transmitted dat cache reply traffic packet
  *  counter
+ * @BATADV_CNT_NC_CODE: transmitted nc-combined traffic packet counter
+ * @BATADV_CNT_NC_CODE_BYTES: transmitted nc-combined traffic bytes counter
+ * @BATADV_CNT_NC_RECODE: transmitted nc-recombined traffic packet counter
+ * @BATADV_CNT_NC_RECODE_BYTES: transmitted nc-recombined traffic bytes counter
  * @BATADV_CNT_NUM: number of traffic counters
  */
 enum batadv_counters {

@@ -302,6 +306,12 @@ enum batadv_counters {
 	BATADV_CNT_DAT_PUT_RX,
 	BATADV_CNT_DAT_CACHED_REPLY_TX,
 #endif
+#ifdef CONFIG_BATMAN_ADV_NC
+	BATADV_CNT_NC_CODE,
+	BATADV_CNT_NC_CODE_BYTES,
+	BATADV_CNT_NC_RECODE,
+	BATADV_CNT_NC_RECODE_BYTES,
+#endif
 	BATADV_CNT_NUM,
 };
 

@@ -797,6 +807,16 @@ struct batadv_nc_packet {
 };
 
 /**
+ * batadv_skb_cb - control buffer structure used to store private data relevant
+ *  to batman-adv in the skb->cb buffer in skbs.
+ * @decoded: Marks a skb as decoded, which is checked when searching for coding
+ *  opportunities in network-coding.c
+ */
+struct batadv_skb_cb {
+	bool decoded;
+};
+
+/**
  * struct batadv_forw_packet - structure for bcast packets to be sent/forwarded
  * @list: list node for batadv_socket_client::queue_list
  * @send_time: execution time for delayed_work (packet sending)

index 3c5249d..af96211 100644
@@ -27,6 +27,7 @@
 #include "hard-interface.h"
 
 static struct lock_class_key batadv_nc_coding_hash_lock_class_key;
+static struct lock_class_key batadv_nc_decoding_hash_lock_class_key;
 
 static void batadv_nc_worker(struct work_struct *work);
 

@@ -47,8 +48,9 @@ static void batadv_nc_start_timer(struct batadv_priv *bat_priv)
 int batadv_nc_init(struct batadv_priv *bat_priv)
 {
 	bat_priv->nc.timestamp_fwd_flush = jiffies;
+	bat_priv->nc.timestamp_sniffed_purge = jiffies;
 
-	if (bat_priv->nc.coding_hash)
+	if (bat_priv->nc.coding_hash || bat_priv->nc.decoding_hash)
 		return 0;
 
 	bat_priv->nc.coding_hash = batadv_hash_new(128);

@@ -58,6 +60,13 @@ int batadv_nc_init(struct batadv_priv *bat_priv)
 	batadv_hash_set_lock_class(bat_priv->nc.coding_hash,
 				   &batadv_nc_coding_hash_lock_class_key);
 
+	bat_priv->nc.decoding_hash = batadv_hash_new(128);
+	if (!bat_priv->nc.decoding_hash)
+		goto err;
+
+	batadv_hash_set_lock_class(bat_priv->nc.coding_hash,
+				   &batadv_nc_decoding_hash_lock_class_key);
+
 	INIT_DELAYED_WORK(&bat_priv->nc.work, batadv_nc_worker);
 	batadv_nc_start_timer(bat_priv);
 

@@ -76,6 +85,7 @@ void batadv_nc_init_bat_priv(struct batadv_priv *bat_priv)
 	atomic_set(&bat_priv->network_coding, 1);
 	bat_priv->nc.min_tq = 200;
 	bat_priv->nc.max_fwd_delay = 10;
+	bat_priv->nc.max_buffer_time = 200;
 }
 
 /**

@@ -176,6 +186,26 @@ static bool batadv_nc_to_purge_nc_path_coding(struct batadv_priv *bat_priv,
 }
 
 /**
+ * batadv_nc_to_purge_nc_path_decoding - checks whether an nc path has timed out
+ * @bat_priv: the bat priv with all the soft interface information
+ * @nc_path: the nc path to check
+ *
+ * Returns true if the entry has to be purged now, false otherwise
+ */
+static bool batadv_nc_to_purge_nc_path_decoding(struct batadv_priv *bat_priv,
+						struct batadv_nc_path *nc_path)
+{
+	if (atomic_read(&bat_priv->mesh_state) != BATADV_MESH_ACTIVE)
+		return true;
+
+	/* purge the path when no packets has been added for 10 times the
+	 * max_buffer time
+	 */
+	return batadv_has_timed_out(nc_path->last_valid,
+				    bat_priv->nc.max_buffer_time*10);
+}
+
+/**
  * batadv_nc_purge_orig_nc_nodes - go through list of nc nodes and purge stale
  *  entries
  * @bat_priv: the bat priv with all the soft interface information

@@ -446,6 +476,43 @@ static void batadv_nc_send_packet(struct batadv_nc_packet *nc_packet)
 }
 
 /**
+ * batadv_nc_sniffed_purge - Checks timestamp of given sniffed nc_packet.
+ * @bat_priv: the bat priv with all the soft interface information
+ * @nc_path: the nc path the packet belongs to
+ * @nc_packet: the nc packet to be checked
+ *
+ * Checks whether the given sniffed (overheard) nc_packet has hit its buffering
+ * timeout. If so, the packet is no longer kept and the entry deleted from the
+ * queue. Has to be called with the appropriate locks.
+ *
+ * Returns false as soon as the entry in the fifo queue has not been timed out
+ * yet and true otherwise.
+ */
+static bool batadv_nc_sniffed_purge(struct batadv_priv *bat_priv,
+				    struct batadv_nc_path *nc_path,
+				    struct batadv_nc_packet *nc_packet)
+{
+	unsigned long timeout = bat_priv->nc.max_buffer_time;
+	bool res = false;
+
+	/* Packets are added to tail, so the remaining packets did not time
+	 * out and we can stop processing the current queue
+	 */
+	if (atomic_read(&bat_priv->mesh_state) == BATADV_MESH_ACTIVE &&
+	    !batadv_has_timed_out(nc_packet->timestamp, timeout))
+		goto out;
+
+	/* purge nc packet */
+	list_del(&nc_packet->list);
+	batadv_nc_packet_free(nc_packet);
+
+	res = true;
+
+out:
+	return res;
+}
+
+/**
  * batadv_nc_fwd_flush - Checks the timestamp of the given nc packet.
  * @bat_priv: the bat priv with all the soft interface information
  * @nc_path: the nc path the packet belongs to

@@ -546,6 +613,8 @@ static void batadv_nc_worker(struct work_struct *work)
 	batadv_nc_purge_orig_hash(bat_priv);
 	batadv_nc_purge_paths(bat_priv, bat_priv->nc.coding_hash,
 			      batadv_nc_to_purge_nc_path_coding);
+	batadv_nc_purge_paths(bat_priv, bat_priv->nc.decoding_hash,
+			      batadv_nc_to_purge_nc_path_decoding);
 
 	timeout = bat_priv->nc.max_fwd_delay;
 

@@ -555,6 +624,13 @@ static void batadv_nc_worker(struct work_struct *work)
 		bat_priv->nc.timestamp_fwd_flush = jiffies;
 	}
 
+	if (batadv_has_timed_out(bat_priv->nc.timestamp_sniffed_purge,
+				 bat_priv->nc.max_buffer_time)) {
+		batadv_nc_process_nc_paths(bat_priv, bat_priv->nc.decoding_hash,
+					   batadv_nc_sniffed_purge);
+		bat_priv->nc.timestamp_sniffed_purge = jiffies;
+	}
+
 	/* Schedule a new check */
 	batadv_nc_start_timer(bat_priv);
 }

@@ -1151,6 +1227,41 @@ batadv_nc_skb_src_search(struct batadv_priv *bat_priv,
 }
 
 /**
+ * batadv_nc_skb_store_before_coding - set the ethernet src and dst of the
+ *  unicast skb before it is stored for use in later decoding
+ * @bat_priv: the bat priv with all the soft interface information
+ * @skb: data skb to store
+ * @eth_dst_new: new destination mac address of skb
+ */
+static void batadv_nc_skb_store_before_coding(struct batadv_priv *bat_priv,
+					      struct sk_buff *skb,
+					      uint8_t *eth_dst_new)
+{
+	struct ethhdr *ethhdr;
+
+	/* Copy skb header to change the mac header */
+	skb = pskb_copy(skb, GFP_ATOMIC);
+	if (!skb)
+		return;
+
+	/* Set the mac header as if we actually sent the packet uncoded */
+	ethhdr = (struct ethhdr *)skb_mac_header(skb);
+	memcpy(ethhdr->h_source, ethhdr->h_dest, ETH_ALEN);
+	memcpy(ethhdr->h_dest, eth_dst_new, ETH_ALEN);
+
+	/* Set data pointer to MAC header to mimic packets from our tx path */
+	skb_push(skb, ETH_HLEN);
+
+	/* Add the packet to the decoding packet pool */
+	batadv_nc_skb_store_for_decoding(bat_priv, skb);
+
+	/* batadv_nc_skb_store_for_decoding() clones the skb, so we must free
+	 * our ref
+	 */
+	kfree_skb(skb);
+}
+
+/**
  * batadv_nc_skb_dst_search - Loops through list of neighboring nodes to dst.
  * @skb: data skb to forward
  * @neigh_node: next hop to forward packet to

@@ -1189,6 +1300,12 @@ static bool batadv_nc_skb_dst_search(struct sk_buff *skb,
 	if (!nc_packet)
 		return false;
 
+	/* Save packets for later decoding */
+	batadv_nc_skb_store_before_coding(bat_priv, skb,
+					  neigh_node->addr);
+	batadv_nc_skb_store_before_coding(bat_priv, nc_packet->skb,
+					  nc_packet->neigh_node->addr);
+
 	/* Code and send packets */
 	if (batadv_nc_code_packets(bat_priv, skb, ethhdr, nc_packet,
 				   neigh_node))

@@ -1296,14 +1413,98 @@ out:
 }
 
 /**
+ * batadv_nc_skb_store_for_decoding - save a clone of the skb which can be used
+ *  when decoding coded packets
+ * @bat_priv: the bat priv with all the soft interface information
+ * @skb: data skb to store
+ */
+void batadv_nc_skb_store_for_decoding(struct batadv_priv *bat_priv,
+				      struct sk_buff *skb)
+{
+	struct batadv_unicast_packet *packet;
+	struct batadv_nc_path *nc_path;
+	struct ethhdr *ethhdr = (struct ethhdr *)skb_mac_header(skb);
+	__be32 packet_id;
+	u8 *payload;
+
+	/* Check if network coding is enabled */
+	if (!atomic_read(&bat_priv->network_coding))
+		goto out;
+
+	/* Check for supported packet type */
+	payload = skb_network_header(skb);
+	packet = (struct batadv_unicast_packet *)payload;
+	if (packet->header.packet_type != BATADV_UNICAST)
+		goto out;
+
+	/* Find existing nc_path or create a new */
+	nc_path = batadv_nc_get_path(bat_priv,
+				     bat_priv->nc.decoding_hash,
+				     ethhdr->h_source,
+				     ethhdr->h_dest);
+
+	if (!nc_path)
+		goto out;
+
+	/* Clone skb and adjust skb->data to point at batman header */
+	skb = skb_clone(skb, GFP_ATOMIC);
+	if (unlikely(!skb))
+		goto free_nc_path;
+
+	if (unlikely(!pskb_may_pull(skb, ETH_HLEN)))
+		goto free_skb;
+
+	if (unlikely(!skb_pull_rcsum(skb, ETH_HLEN)))
+		goto free_skb;
+
+	/* Add skb to nc_path */
+	packet_id = batadv_skb_crc32(skb, payload + sizeof(*packet));
+	if (!batadv_nc_skb_add_to_path(skb, nc_path, NULL, packet_id))
+		goto free_skb;
+
+	batadv_inc_counter(bat_priv, BATADV_CNT_NC_BUFFER);
+	return;
+
+free_skb:
+	kfree_skb(skb);
+free_nc_path:
+	batadv_nc_path_free_ref(nc_path);
+out:
+	return;
+}
+
+/**
+ * batadv_nc_skb_store_sniffed_unicast - check if a received unicast packet
+ *  should be saved in the decoding buffer and, if so, store it there
+ * @bat_priv: the bat priv with all the soft interface information
+ * @skb: unicast skb to store
+ */
+void batadv_nc_skb_store_sniffed_unicast(struct batadv_priv *bat_priv,
+					 struct sk_buff *skb)
+{
+	struct ethhdr *ethhdr = (struct ethhdr *)skb_mac_header(skb);
+
+	if (batadv_is_my_mac(ethhdr->h_dest))
+		return;
+
+	/* Set data pointer to MAC header to mimic packets from our tx path */
+	skb_push(skb, ETH_HLEN);
+
+	batadv_nc_skb_store_for_decoding(bat_priv, skb);
+}
+
+/**
  * batadv_nc_free - clean up network coding memory
  * @bat_priv: the bat priv with all the soft interface information
  */
 void batadv_nc_free(struct batadv_priv *bat_priv)
 {
 	cancel_delayed_work_sync(&bat_priv->nc.work);
+
 	batadv_nc_purge_paths(bat_priv, bat_priv->nc.coding_hash, NULL);
 	batadv_hash_destroy(bat_priv->nc.coding_hash);
+	batadv_nc_purge_paths(bat_priv, bat_priv->nc.decoding_hash, NULL);
+	batadv_hash_destroy(bat_priv->nc.decoding_hash);
 }
 
 /**

@@ -1385,6 +1586,11 @@ int batadv_nc_init_debugfs(struct batadv_priv *bat_priv)
 	if (!file)
 		goto out;
 
+	file = debugfs_create_u32("max_buffer_time", S_IRUGO | S_IWUSR, nc_dir,
+				  &bat_priv->nc.max_buffer_time);
+	if (!file)
+		goto out;
+
 	return 0;
 
 out:

index 6e53cc8..352c693 100644
@@ -38,6 +38,10 @@ void batadv_nc_init_orig(struct batadv_orig_node *orig_node);
 bool batadv_nc_skb_forward(struct sk_buff *skb,
 			   struct batadv_neigh_node *neigh_node,
 			   struct ethhdr *ethhdr);
+void batadv_nc_skb_store_for_decoding(struct batadv_priv *bat_priv,
+				      struct sk_buff *skb);
+void batadv_nc_skb_store_sniffed_unicast(struct batadv_priv *bat_priv,
+					 struct sk_buff *skb);
 int batadv_nc_nodes_seq_print_text(struct seq_file *seq, void *offset);
 int batadv_nc_init_debugfs(struct batadv_priv *bat_priv);
 

@@ -89,6 +93,20 @@ static inline bool batadv_nc_skb_forward(struct sk_buff *skb,
 	return false;
 }
 
+static inline void
+batadv_nc_skb_store_for_decoding(struct batadv_priv *bat_priv,
+				 struct sk_buff *skb)
+{
+	return;
+}
+
+static inline void
+batadv_nc_skb_store_sniffed_unicast(struct batadv_priv *bat_priv,
+				    struct sk_buff *skb)
+{
+	return;
+}
+
 static inline int batadv_nc_nodes_seq_print_text(struct seq_file *seq,
 						 void *offset)
 {

index 2765fc3..622b1f9 100644
@@ -1039,7 +1039,7 @@ int batadv_recv_unicast_packet(struct sk_buff *skb,
 	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);
+	int check, hdr_size = sizeof(*unicast_packet);
 	bool is4addr;
 
 	unicast_packet = (struct batadv_unicast_packet *)skb->data;

@@ -1050,7 +1050,16 @@ int batadv_recv_unicast_packet(struct sk_buff *skb,
 	if (is4addr)
 		hdr_size = sizeof(*unicast_4addr_packet);
 
-	if (batadv_check_unicast_packet(skb, hdr_size) < 0)
+	/* function returns -EREMOTE for promiscuous packets */
+	check = batadv_check_unicast_packet(skb, hdr_size);
+
+	/* Even though the packet is not for us, we might save it to use for
+	 * decoding a later received coded packet
+	 */
+	if (check == -EREMOTE)
+		batadv_nc_skb_store_sniffed_unicast(bat_priv, skb);
+
+	if (check < 0)
 		return NET_RX_DROP;
 
 	if (!batadv_check_unicast_ttvn(bat_priv, skb))

index 80ca65f..0a0bb45 100644
@@ -27,6 +27,7 @@
 #include "vis.h"
 #include "gateway_common.h"
 #include "originator.h"
+#include "network-coding.h"
 
 #include <linux/if_ether.h>
 

@@ -39,6 +40,7 @@ int batadv_send_skb_packet(struct sk_buff *skb,
 			   struct batadv_hard_iface *hard_iface,
 			   const uint8_t *dst_addr)
 {
+	struct batadv_priv *bat_priv = netdev_priv(hard_iface->soft_iface);
 	struct ethhdr *ethhdr;
 
 	if (hard_iface->if_status != BATADV_IF_ACTIVE)

@@ -70,6 +72,9 @@ int batadv_send_skb_packet(struct sk_buff *skb,
 
 	skb->dev = hard_iface->net_dev;
 
+	/* Save a clone of the skb to use when decoding coded packets */
+	batadv_nc_skb_store_for_decoding(bat_priv, skb);
+
 	/* dev_queue_xmit() returns a negative result on error.	 However on
 	 * congestion and traffic shaping, it drops and returns NET_XMIT_DROP
 	 * (which is > 0). This will not be treated as an error.

index 7e463c3..75204ec 100644
@@ -670,6 +670,7 @@ static const struct {
 	{ "nc_code_bytes" },
 	{ "nc_recode" },
 	{ "nc_recode_bytes" },
+	{ "nc_buffer" },
 #endif
 };
 

index 8d72160..08a3c30 100644
@@ -279,6 +279,7 @@ struct batadv_bcast_duplist_entry {
  * @BATADV_CNT_NC_CODE_BYTES: transmitted nc-combined traffic bytes counter
  * @BATADV_CNT_NC_RECODE: transmitted nc-recombined traffic packet counter
  * @BATADV_CNT_NC_RECODE_BYTES: transmitted nc-recombined traffic bytes counter
+ * @BATADV_CNT_NC_BUFFER: counter for packets buffered for later nc decoding
  * @BATADV_CNT_NUM: number of traffic counters
  */
 enum batadv_counters {

@@ -311,6 +312,7 @@ enum batadv_counters {
 	BATADV_CNT_NC_CODE_BYTES,
 	BATADV_CNT_NC_RECODE,
 	BATADV_CNT_NC_RECODE_BYTES,
+	BATADV_CNT_NC_BUFFER,
 #endif
 	BATADV_CNT_NUM,
 };

@@ -453,18 +455,27 @@ struct batadv_priv_dat {
  * @debug_dir: dentry for nc subdir in batman-adv directory in debugfs
  * @min_tq: only consider neighbors for encoding if neigh_tq > min_tq
  * @max_fwd_delay: maximum packet forward delay to allow coding of packets
+ * @max_buffer_time: buffer time for sniffed packets used to decoding
  * @timestamp_fwd_flush: timestamp of last forward packet queue flush
+ * @timestamp_sniffed_purge: timestamp of last sniffed packet queue purge
  * @coding_hash: Hash table used to buffer skbs while waiting for another
  *  incoming skb to code it with. Skbs are added to the buffer just before being
  *  forwarded in routing.c
+ * @decoding_hash: Hash table used to buffer skbs that might be needed to decode
+ *  a received coded skb. The buffer is used for 1) skbs arriving on the
+ *  soft-interface; 2) skbs overheard on the hard-interface; and 3) skbs
+ *  forwarded by batman-adv.
  */
 struct batadv_priv_nc {
 	struct delayed_work work;
 	struct dentry *debug_dir;
 	u8 min_tq;
 	u32 max_fwd_delay;
+	u32 max_buffer_time;
 	unsigned long timestamp_fwd_flush;
+	unsigned long timestamp_sniffed_purge;
 	struct batadv_hashtable *coding_hash;
+	struct batadv_hashtable *decoding_hash;
 };
 
 /**

index af96211..57069ae 100644
@@ -25,11 +25,14 @@
 #include "send.h"
 #include "originator.h"
 #include "hard-interface.h"
+#include "routing.h"
 
 static struct lock_class_key batadv_nc_coding_hash_lock_class_key;
 static struct lock_class_key batadv_nc_decoding_hash_lock_class_key;
 
 static void batadv_nc_worker(struct work_struct *work);
+static int batadv_nc_recv_coded_packet(struct sk_buff *skb,
+				       struct batadv_hard_iface *recv_if);
 
 /**
  * batadv_nc_start_timer - initialise the nc periodic worker

@@ -67,6 +70,11 @@ int batadv_nc_init(struct batadv_priv *bat_priv)
 	batadv_hash_set_lock_class(bat_priv->nc.coding_hash,
 				   &batadv_nc_decoding_hash_lock_class_key);
 
+	/* Register our packet type */
+	if (batadv_recv_handler_register(BATADV_CODED,
+					 batadv_nc_recv_coded_packet) < 0)
+		goto err;
+
 	INIT_DELAYED_WORK(&bat_priv->nc.work, batadv_nc_worker);
 	batadv_nc_start_timer(bat_priv);
 

@@ -1494,11 +1502,237 @@ void batadv_nc_skb_store_sniffed_unicast(struct batadv_priv *bat_priv,
 }
 
 /**
+ * batadv_nc_skb_decode_packet - decode given skb using the decode data stored
+ *  in nc_packet
+ * @skb: unicast skb to decode
+ * @nc_packet: decode data needed to decode the skb
+ *
+ * Returns pointer to decoded unicast packet if the packet was decoded or NULL
+ * in case of an error.
+ */
+static struct batadv_unicast_packet *
+batadv_nc_skb_decode_packet(struct sk_buff *skb,
+			    struct batadv_nc_packet *nc_packet)
+{
+	const int h_size = sizeof(struct batadv_unicast_packet);
+	const int h_diff = sizeof(struct batadv_coded_packet) - h_size;
+	struct batadv_unicast_packet *unicast_packet;
+	struct batadv_coded_packet coded_packet_tmp;
+	struct ethhdr *ethhdr, ethhdr_tmp;
+	uint8_t *orig_dest, ttl, ttvn;
+	unsigned int coding_len;
+
+	/* Save headers temporarily */
+	memcpy(&coded_packet_tmp, skb->data, sizeof(coded_packet_tmp));
+	memcpy(&ethhdr_tmp, skb_mac_header(skb), sizeof(ethhdr_tmp));
+
+	if (skb_cow(skb, 0) < 0)
+		return NULL;
+
+	if (unlikely(!skb_pull_rcsum(skb, h_diff)))
+		return NULL;
+
+	/* Data points to batman header, so set mac header 14 bytes before
+	 * and network to data
+	 */
+	skb_set_mac_header(skb, -ETH_HLEN);
+	skb_reset_network_header(skb);
+
+	/* Reconstruct original mac header */
+	ethhdr = (struct ethhdr *)skb_mac_header(skb);
+	memcpy(ethhdr, &ethhdr_tmp, sizeof(*ethhdr));
+
+	/* Select the correct unicast header information based on the location
+	 * of our mac address in the coded_packet header
+	 */
+	if (batadv_is_my_mac(coded_packet_tmp.second_dest)) {
+		/* If we are the second destination the packet was overheard,
+		 * so the Ethernet address must be copied to h_dest and
+		 * pkt_type changed from PACKET_OTHERHOST to PACKET_HOST
+		 */
+		memcpy(ethhdr->h_dest, coded_packet_tmp.second_dest, ETH_ALEN);
+		skb->pkt_type = PACKET_HOST;
+
+		orig_dest = coded_packet_tmp.second_orig_dest;
+		ttl = coded_packet_tmp.second_ttl;
+		ttvn = coded_packet_tmp.second_ttvn;
+	} else {
+		orig_dest = coded_packet_tmp.first_orig_dest;
+		ttl = coded_packet_tmp.header.ttl;
+		ttvn = coded_packet_tmp.first_ttvn;
+	}
+
+	coding_len = ntohs(coded_packet_tmp.coded_len);
+
+	if (coding_len > skb->len)
+		return NULL;
+
+	/* Here the magic is reversed:
+	 *   extract the missing packet from the received coded packet
+	 */
+	batadv_nc_memxor(skb->data + h_size,
+			 nc_packet->skb->data + h_size,
+			 coding_len);
+
+	/* Resize decoded skb if decoded with larger packet */
+	if (nc_packet->skb->len > coding_len + h_size)
+		pskb_trim_rcsum(skb, coding_len + h_size);
+
+	/* Create decoded unicast packet */
+	unicast_packet = (struct batadv_unicast_packet *)skb->data;
+	unicast_packet->header.packet_type = BATADV_UNICAST;
+	unicast_packet->header.version = BATADV_COMPAT_VERSION;
+	unicast_packet->header.ttl = ttl;
+	memcpy(unicast_packet->dest, orig_dest, ETH_ALEN);
+	unicast_packet->ttvn = ttvn;
+
+	batadv_nc_packet_free(nc_packet);
+	return unicast_packet;
+}
+
+/**
+ * batadv_nc_find_decoding_packet - search through buffered decoding data to
+ *  find the data needed to decode the coded packet
+ * @bat_priv: the bat priv with all the soft interface information
+ * @ethhdr: pointer to the ethernet header inside the coded packet
+ * @coded: coded packet we try to find decode data for
+ *
+ * Returns pointer to nc packet if the needed data was found or NULL otherwise.
+ */
+static struct batadv_nc_packet *
+batadv_nc_find_decoding_packet(struct batadv_priv *bat_priv,
+			       struct ethhdr *ethhdr,
+			       struct batadv_coded_packet *coded)
+{
+	struct batadv_hashtable *hash = bat_priv->nc.decoding_hash;
+	struct hlist_node *hnode;
+	struct batadv_nc_packet *tmp_nc_packet, *nc_packet = NULL;
+	struct batadv_nc_path *nc_path, nc_path_key;
+	uint8_t *dest, *source;
+	__be32 packet_id;
+	int index;
+
+	if (!hash)
+		return NULL;
+
+	/* Select the correct packet id based on the location of our mac-addr */
+	dest = ethhdr->h_source;
+	if (!batadv_is_my_mac(coded->second_dest)) {
+		source = coded->second_source;
+		packet_id = coded->second_crc;
+	} else {
+		source = coded->first_source;
+		packet_id = coded->first_crc;
+	}
+
+	batadv_nc_hash_key_gen(&nc_path_key, source, dest);
+	index = batadv_nc_hash_choose(&nc_path_key, hash->size);
+
+	/* Search for matching coding path */
+	rcu_read_lock();
+	hlist_for_each_entry_rcu(nc_path, hnode, &hash->table[index],
+				 hash_entry) {
+		/* Find matching nc_packet */
+		spin_lock_bh(&nc_path->packet_list_lock);
+		list_for_each_entry(tmp_nc_packet,
+				    &nc_path->packet_list, list) {
+			if (packet_id == tmp_nc_packet->packet_id) {
+				list_del(&tmp_nc_packet->list);
+
+				nc_packet = tmp_nc_packet;
+				break;
+			}
+		}
+		spin_unlock_bh(&nc_path->packet_list_lock);
+
+		if (nc_packet)
+			break;
+	}
+	rcu_read_unlock();
+
+	if (!nc_packet)
+		batadv_dbg(BATADV_DBG_NC, bat_priv,
+			   "No decoding packet found for %u\n", packet_id);
+
+	return nc_packet;
+}
+
+/**
+ * batadv_nc_recv_coded_packet - try to decode coded packet and enqueue the
+ *  resulting unicast packet
+ * @skb: incoming coded packet
+ * @recv_if: pointer to interface this packet was received on
+ */
+static int batadv_nc_recv_coded_packet(struct sk_buff *skb,
+				       struct batadv_hard_iface *recv_if)
+{
+	struct batadv_priv *bat_priv = netdev_priv(recv_if->soft_iface);
+	struct batadv_unicast_packet *unicast_packet;
+	struct batadv_coded_packet *coded_packet;
+	struct batadv_nc_packet *nc_packet;
+	struct ethhdr *ethhdr;
+	int hdr_size = sizeof(*coded_packet);
+
+	/* Check if network coding is enabled */
+	if (!atomic_read(&bat_priv->network_coding))
+		return NET_RX_DROP;
+
+	/* Make sure we can access (and remove) header */
+	if (unlikely(!pskb_may_pull(skb, hdr_size)))
+		return NET_RX_DROP;
+
+	coded_packet = (struct batadv_coded_packet *)skb->data;
+	ethhdr = (struct ethhdr *)skb_mac_header(skb);
+
+	/* Verify frame is destined for us */
+	if (!batadv_is_my_mac(ethhdr->h_dest) &&
+	    !batadv_is_my_mac(coded_packet->second_dest))
+		return NET_RX_DROP;
+
+	/* Update stat counter */
+	if (batadv_is_my_mac(coded_packet->second_dest))
+		batadv_inc_counter(bat_priv, BATADV_CNT_NC_SNIFFED);
+
+	nc_packet = batadv_nc_find_decoding_packet(bat_priv, ethhdr,
+						   coded_packet);
+	if (!nc_packet) {
+		batadv_inc_counter(bat_priv, BATADV_CNT_NC_DECODE_FAILED);
+		return NET_RX_DROP;
+	}
+
+	/* Make skb's linear, because decoding accesses the entire buffer */
+	if (skb_linearize(skb) < 0)
+		goto free_nc_packet;
+
+	if (skb_linearize(nc_packet->skb) < 0)
+		goto free_nc_packet;
+
+	/* Decode the packet */
+	unicast_packet = batadv_nc_skb_decode_packet(skb, nc_packet);
+	if (!unicast_packet) {
+		batadv_inc_counter(bat_priv, BATADV_CNT_NC_DECODE_FAILED);
+		goto free_nc_packet;
+	}
+
+	/* Mark packet as decoded to do correct recoding when forwarding */
+	BATADV_SKB_CB(skb)->decoded = true;
+	batadv_inc_counter(bat_priv, BATADV_CNT_NC_DECODE);
+	batadv_add_counter(bat_priv, BATADV_CNT_NC_DECODE_BYTES,
+			   skb->len + ETH_HLEN);
+	return batadv_recv_unicast_packet(skb, recv_if);
+
+free_nc_packet:
+	batadv_nc_packet_free(nc_packet);
+	return NET_RX_DROP;
+}
+
+/**
  * batadv_nc_free - clean up network coding memory
  * @bat_priv: the bat priv with all the soft interface information
  */
 void batadv_nc_free(struct batadv_priv *bat_priv)
 {
+	batadv_recv_handler_unregister(BATADV_CODED);
 	cancel_delayed_work_sync(&bat_priv->nc.work);
 
 	batadv_nc_purge_paths(bat_priv, bat_priv->nc.coding_hash, NULL);

index 75204ec..f93ae42 100644
@@ -671,6 +671,10 @@ static const struct {
 	{ "nc_recode" },
 	{ "nc_recode_bytes" },
 	{ "nc_buffer" },
+	{ "nc_decode" },
+	{ "nc_decode_bytes" },
+	{ "nc_decode_failed" },
+	{ "nc_sniffed" },
 #endif
 };
 

index 08a3c30..76dec7c 100644
@@ -280,6 +280,12 @@ struct batadv_bcast_duplist_entry {
  * @BATADV_CNT_NC_RECODE: transmitted nc-recombined traffic packet counter
  * @BATADV_CNT_NC_RECODE_BYTES: transmitted nc-recombined traffic bytes counter
  * @BATADV_CNT_NC_BUFFER: counter for packets buffered for later nc decoding
+ * @BATADV_CNT_NC_DECODE: received and nc-decoded traffic packet counter
+ * @BATADV_CNT_NC_DECODE_BYTES: received and nc-decoded traffic bytes counter
+ * @BATADV_CNT_NC_DECODE_FAILED: received and decode-failed traffic packet
+ *  counter
+ * @BATADV_CNT_NC_SNIFFED: counter for nc-decoded packets received in promisc
+ *  mode.
  * @BATADV_CNT_NUM: number of traffic counters
  */
 enum batadv_counters {

@@ -313,6 +319,10 @@ enum batadv_counters {
 	BATADV_CNT_NC_RECODE,
 	BATADV_CNT_NC_RECODE_BYTES,
 	BATADV_CNT_NC_BUFFER,
+	BATADV_CNT_NC_DECODE,
+	BATADV_CNT_NC_DECODE_BYTES,
+	BATADV_CNT_NC_DECODE_FAILED,
+	BATADV_CNT_NC_SNIFFED,
 #endif
 	BATADV_CNT_NUM,
 };