1 files changed, 386 insertions, 0 deletions
diff --git a/net/batman-adv/send.c b/net/batman-adv/send.c
new file mode 100644
index 00000000..263cfd1c
--- /dev/null
+++ b/net/batman-adv/send.c
@@ -0,0 +1,386 @@
+/* Copyright (C) 2007-2013 B.A.T.M.A.N. contributors:
+ *
+ * Marek Lindner, Simon Wunderlich
+ *
+ * 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 "main.h"
+#include "distributed-arp-table.h"
+#include "send.h"
+#include "routing.h"
+#include "translation-table.h"
+#include "soft-interface.h"
+#include "hard-interface.h"
+#include "vis.h"
+#include "gateway_common.h"
+#include "originator.h"
+#include "network-coding.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
+ * specified batman interface
+ */
+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)
+		goto send_skb_err;
+
+	if (unlikely(!hard_iface->net_dev))
+		goto send_skb_err;
+
+	if (!(hard_iface->net_dev->flags & IFF_UP)) {
+		pr_warn("Interface %s is not up - can't send packet via that interface!\n",
+			hard_iface->net_dev->name);
+		goto send_skb_err;
+	}
+
+	/* push to the ethernet header. */
+	if (batadv_skb_head_push(skb, ETH_HLEN) < 0)
+		goto send_skb_err;
+
+	skb_reset_mac_header(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(ETH_P_BATMAN);
+
+	skb_set_network_header(skb, ETH_HLEN);
+	skb->priority = TC_PRIO_CONTROL;
+	skb->protocol = __constant_htons(ETH_P_BATMAN);
+
+	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.
+	 */
+	return dev_queue_xmit(skb);
+send_skb_err:
+	kfree_skb(skb);
+	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);
+
+	if ((hard_iface->if_status == BATADV_IF_NOT_IN_USE) ||
+	    (hard_iface->if_status == BATADV_IF_TO_BE_REMOVED))
+		return;
+
+	/* the interface gets activated here to avoid race conditions between
+	 * the moment of activating the interface in
+	 * hardif_activate_interface() where the originator mac is set and
+	 * outdated packets (especially uninitialized mac addresses) in the
+	 * packet queue
+	 */
+	if (hard_iface->if_status == BATADV_IF_TO_BE_ACTIVATED)
+		hard_iface->if_status = BATADV_IF_ACTIVE;
+
+	bat_priv->bat_algo_ops->bat_ogm_schedule(hard_iface);
+}
+
+static void batadv_forw_packet_free(struct batadv_forw_packet *forw_packet)
+{
+	if (forw_packet->skb)
+		kfree_skb(forw_packet->skb);
+	if (forw_packet->if_incoming)
+		batadv_hardif_free_ref(forw_packet->if_incoming);
+	kfree(forw_packet);
+}
+
+static void
+_batadv_add_bcast_packet_to_list(struct batadv_priv *bat_priv,
+				 struct batadv_forw_packet *forw_packet,
+				 unsigned long send_time)
+{
+	INIT_HLIST_NODE(&forw_packet->list);
+
+	/* add new packet to packet list */
+	spin_lock_bh(&bat_priv->forw_bcast_list_lock);
+	hlist_add_head(&forw_packet->list, &bat_priv->forw_bcast_list);
+	spin_unlock_bh(&bat_priv->forw_bcast_list_lock);
+
+	/* start timer for this packet */
+	queue_delayed_work(batadv_event_workqueue, &forw_packet->delayed_work,
+			   send_time);
+}
+
+/* add a broadcast packet to the queue and setup timers. broadcast packets
+ * are sent multiple times to increase probability for being received.
+ *
+ * This function returns NETDEV_TX_OK on success and NETDEV_TX_BUSY on
+ * errors.
+ *
+ * The skb is not consumed, so the caller should make sure that the
+ * skb is freed.
+ */
+int batadv_add_bcast_packet_to_list(struct batadv_priv *bat_priv,
+				    const struct sk_buff *skb,
+				    unsigned long delay)
+{
+	struct batadv_hard_iface *primary_if = NULL;
+	struct batadv_forw_packet *forw_packet;
+	struct batadv_bcast_packet *bcast_packet;
+	struct sk_buff *newskb;
+
+	if (!batadv_atomic_dec_not_zero(&bat_priv->bcast_queue_left)) {
+		batadv_dbg(BATADV_DBG_BATMAN, bat_priv,
+			   "bcast packet queue full\n");
+		goto out;
+	}
+
+	primary_if = batadv_primary_if_get_selected(bat_priv);
+	if (!primary_if)
+		goto out_and_inc;
+
+	forw_packet = kmalloc(sizeof(*forw_packet), GFP_ATOMIC);
+
+	if (!forw_packet)
+		goto out_and_inc;
+
+	newskb = skb_copy(skb, GFP_ATOMIC);
+	if (!newskb)
+		goto packet_free;
+
+	/* as we have a copy now, it is safe to decrease the TTL */
+	bcast_packet = (struct batadv_bcast_packet *)newskb->data;
+	bcast_packet->header.ttl--;
+
+	skb_reset_mac_header(newskb);
+
+	forw_packet->skb = newskb;
+	forw_packet->if_incoming = primary_if;
+
+	/* how often did we send the bcast packet ? */
+	forw_packet->num_packets = 0;
+
+	INIT_DELAYED_WORK(&forw_packet->delayed_work,
+			  batadv_send_outstanding_bcast_packet);
+
+	_batadv_add_bcast_packet_to_list(bat_priv, forw_packet, delay);
+	return NETDEV_TX_OK;
+
+packet_free:
+	kfree(forw_packet);
+out_and_inc:
+	atomic_inc(&bat_priv->bcast_queue_left);
+out:
+	if (primary_if)
+		batadv_hardif_free_ref(primary_if);
+	return NETDEV_TX_BUSY;
+}
+
+static void batadv_send_outstanding_bcast_packet(struct work_struct *work)
+{
+	struct batadv_hard_iface *hard_iface;
+	struct delayed_work *delayed_work;
+	struct batadv_forw_packet *forw_packet;
+	struct sk_buff *skb1;
+	struct net_device *soft_iface;
+	struct batadv_priv *bat_priv;
+
+	delayed_work = container_of(work, struct delayed_work, work);
+	forw_packet = container_of(delayed_work, struct batadv_forw_packet,
+				   delayed_work);
+	soft_iface = forw_packet->if_incoming->soft_iface;
+	bat_priv = netdev_priv(soft_iface);
+
+	spin_lock_bh(&bat_priv->forw_bcast_list_lock);
+	hlist_del(&forw_packet->list);
+	spin_unlock_bh(&bat_priv->forw_bcast_list_lock);
+
+	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) {
+		if (hard_iface->soft_iface != soft_iface)
+			continue;
+
+		/* send a copy of the saved skb */
+		skb1 = skb_clone(forw_packet->skb, GFP_ATOMIC);
+		if (skb1)
+			batadv_send_skb_packet(skb1, hard_iface,
+					       batadv_broadcast_addr);
+	}
+	rcu_read_unlock();
+
+	forw_packet->num_packets++;
+
+	/* if we still have some more bcasts to send */
+	if (forw_packet->num_packets < 3) {
+		_batadv_add_bcast_packet_to_list(bat_priv, forw_packet,
+						 msecs_to_jiffies(5));
+		return;
+	}
+
+out:
+	batadv_forw_packet_free(forw_packet);
+	atomic_inc(&bat_priv->bcast_queue_left);
+}
+
+void batadv_send_outstanding_bat_ogm_packet(struct work_struct *work)
+{
+	struct delayed_work *delayed_work;
+	struct batadv_forw_packet *forw_packet;
+	struct batadv_priv *bat_priv;
+
+	delayed_work = container_of(work, struct delayed_work, work);
+	forw_packet = container_of(delayed_work, struct batadv_forw_packet,
+				   delayed_work);
+	bat_priv = netdev_priv(forw_packet->if_incoming->soft_iface);
+	spin_lock_bh(&bat_priv->forw_bat_list_lock);
+	hlist_del(&forw_packet->list);
+	spin_unlock_bh(&bat_priv->forw_bat_list_lock);
+
+	if (atomic_read(&bat_priv->mesh_state) == BATADV_MESH_DEACTIVATING)
+		goto out;
+
+	bat_priv->bat_algo_ops->bat_ogm_emit(forw_packet);
+
+	/* we have to have at least one packet in the queue
+	 * to determine the queues wake up time unless we are
+	 * shutting down
+	 */
+	if (forw_packet->own)
+		batadv_schedule_bat_ogm(forw_packet->if_incoming);
+
+out:
+	/* don't count own packet */
+	if (!forw_packet->own)
+		atomic_inc(&bat_priv->batman_queue_left);
+
+	batadv_forw_packet_free(forw_packet);
+}
+
+void
+batadv_purge_outstanding_packets(struct batadv_priv *bat_priv,
+				 const struct batadv_hard_iface *hard_iface)
+{
+	struct batadv_forw_packet *forw_packet;
+	struct hlist_node *safe_tmp_node;
+	bool pending;
+
+	if (hard_iface)
+		batadv_dbg(BATADV_DBG_BATMAN, bat_priv,
+			   "purge_outstanding_packets(): %s\n",
+			   hard_iface->net_dev->name);
+	else
+		batadv_dbg(BATADV_DBG_BATMAN, bat_priv,
+			   "purge_outstanding_packets()\n");
+
+	/* free bcast list */
+	spin_lock_bh(&bat_priv->forw_bcast_list_lock);
+	hlist_for_each_entry_safe(forw_packet, safe_tmp_node,
+				  &bat_priv->forw_bcast_list, list) {
+		/* if purge_outstanding_packets() was called with an argument
+		 * we delete only packets belonging to the given interface
+		 */
+		if ((hard_iface) &&
+		    (forw_packet->if_incoming != hard_iface))
+			continue;
+
+		spin_unlock_bh(&bat_priv->forw_bcast_list_lock);
+
+		/* batadv_send_outstanding_bcast_packet() will lock the list to
+		 * delete the item from the list
+		 */
+		pending = cancel_delayed_work_sync(&forw_packet->delayed_work);
+		spin_lock_bh(&bat_priv->forw_bcast_list_lock);
+
+		if (pending) {
+			hlist_del(&forw_packet->list);
+			batadv_forw_packet_free(forw_packet);
+		}
+	}
+	spin_unlock_bh(&bat_priv->forw_bcast_list_lock);
+
+	/* free batman packet list */
+	spin_lock_bh(&bat_priv->forw_bat_list_lock);
+	hlist_for_each_entry_safe(forw_packet, safe_tmp_node,
+				  &bat_priv->forw_bat_list, list) {
+		/* if purge_outstanding_packets() was called with an argument
+		 * we delete only packets belonging to the given interface
+		 */
+		if ((hard_iface) &&
+		    (forw_packet->if_incoming != hard_iface))
+			continue;
+
+		spin_unlock_bh(&bat_priv->forw_bat_list_lock);
+
+		/* send_outstanding_bat_packet() will lock the list to
+		 * delete the item from the list
+		 */
+		pending = cancel_delayed_work_sync(&forw_packet->delayed_work);
+		spin_lock_bh(&bat_priv->forw_bat_list_lock);
+
+		if (pending) {
+			hlist_del(&forw_packet->list);
+			batadv_forw_packet_free(forw_packet);
+		}
+	}
+	spin_unlock_bh(&bat_priv->forw_bat_list_lock);
+}