batman-adv: Receive fragmented packets and merge

Fragments arriving at their destination are buffered for later merge.
Merged packets are passed to the main receive function as had they never
been fragmented.

Fragments are forwarded without merging if the MTU of the outgoing
interface is smaller than the size of the merged packet.

Signed-off-by: Martin Hundebøll <martin@hundeboll.net>
Signed-off-by: Marek Lindner <lindner_marek@yahoo.de>
Signed-off-by: Antonio Quartulli <antonio@meshcoding.com>

1 files changed, 13 insertions, 1 deletions

diff --git a/net/batman-adv/originator.c b/net/batman-adv/originator.c
index 898b0ce82cc2..a591dc5c321e 100644
--- a/net/batman-adv/originator.c
+++ b/net/batman-adv/originator.c
@@ -28,6 +28,7 @@
 #include "soft-interface.h"
 #include "bridge_loop_avoidance.h"
 #include "network-coding.h"
+#include "fragmentation.h"
 
 /* hash class keys */
 static struct lock_class_key batadv_orig_hash_lock_class_key;
@@ -145,6 +146,8 @@ static void batadv_orig_node_free_rcu(struct rcu_head *rcu)
 	/* Free nc_nodes */
 	batadv_nc_purge_orig(orig_node->bat_priv, orig_node, NULL);
 
+	batadv_frag_purge_orig(orig_node, NULL);
+
 	batadv_tt_global_del_orig(orig_node->bat_priv, orig_node,
 				  "originator timed out");
 
@@ -215,7 +218,7 @@ struct batadv_orig_node *batadv_get_orig_node(struct batadv_priv *bat_priv,
 					      const uint8_t *addr)
 {
 	struct batadv_orig_node *orig_node;
-	int size;
+	int size, i;
 	int hash_added;
 	unsigned long reset_time;
 
@@ -267,6 +270,12 @@ struct batadv_orig_node *batadv_get_orig_node(struct batadv_priv *bat_priv,
 	size = bat_priv->num_ifaces * sizeof(uint8_t);
 	orig_node->bcast_own_sum = kzalloc(size, GFP_ATOMIC);
 
+	for (i = 0; i < BATADV_FRAG_BUFFER_COUNT; i++) {
+		INIT_HLIST_HEAD(&orig_node->fragments[i].head);
+		spin_lock_init(&orig_node->fragments[i].lock);
+		orig_node->fragments[i].size = 0;
+	}
+
 	if (!orig_node->bcast_own_sum)
 		goto free_bcast_own;
 
@@ -388,6 +397,9 @@ static void _batadv_purge_orig(struct batadv_priv *bat_priv)
 				batadv_orig_node_free_ref(orig_node);
 				continue;
 			}
+
+			batadv_frag_purge_orig(orig_node,
+					       batadv_frag_check_entry);
 		}
 		spin_unlock_bh(list_lock);
 	}