1 files changed, 410 insertions, 0 deletions

diff --git a/net/batman-adv/send.c b/net/batman-adv/send.c
new file mode 100644
index 00000000..af7a6741
--- /dev/null
+++ b/net/batman-adv/send.c
@@ -0,0 +1,410 @@
+/*
+ * Copyright (C) 2007-2012 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 "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"
+
+static void send_outstanding_bcast_packet(struct work_struct *work);
+
+/* send out an already prepared packet to the given address via the
+ * specified batman interface */
+int send_skb_packet(struct sk_buff *skb, struct hard_iface *hard_iface,
+		    const uint8_t *dst_addr)
+{
+	struct ethhdr *ethhdr;
+
+	if (hard_iface->if_status != 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_warning("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 (my_skb_head_push(skb, sizeof(*ethhdr)) < 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;
+
+	/* 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;
+}
+
+static void realloc_packet_buffer(struct hard_iface *hard_iface,
+				  int new_len)
+{
+	unsigned char *new_buff;
+
+	new_buff = kmalloc(new_len, GFP_ATOMIC);
+
+	/* keep old buffer if kmalloc should fail */
+	if (new_buff) {
+		memcpy(new_buff, hard_iface->packet_buff,
+		       BATMAN_OGM_LEN);
+
+		kfree(hard_iface->packet_buff);
+		hard_iface->packet_buff = new_buff;
+		hard_iface->packet_len = new_len;
+	}
+}
+
+/* when calling this function (hard_iface == primary_if) has to be true */
+static int prepare_packet_buffer(struct bat_priv *bat_priv,
+				  struct hard_iface *hard_iface)
+{
+	int new_len;
+
+	new_len = BATMAN_OGM_LEN +
+		  tt_len((uint8_t)atomic_read(&bat_priv->tt_local_changes));
+
+	/* if we have too many changes for one packet don't send any
+	 * and wait for the tt table request which will be fragmented */
+	if (new_len > hard_iface->soft_iface->mtu)
+		new_len = BATMAN_OGM_LEN;
+
+	realloc_packet_buffer(hard_iface, new_len);
+
+	atomic_set(&bat_priv->tt_crc, tt_local_crc(bat_priv));
+
+	/* reset the sending counter */
+	atomic_set(&bat_priv->tt_ogm_append_cnt, TT_OGM_APPEND_MAX);
+
+	return tt_changes_fill_buffer(bat_priv,
+				      hard_iface->packet_buff + BATMAN_OGM_LEN,
+				      hard_iface->packet_len - BATMAN_OGM_LEN);
+}
+
+static int reset_packet_buffer(struct bat_priv *bat_priv,
+				struct hard_iface *hard_iface)
+{
+	realloc_packet_buffer(hard_iface, BATMAN_OGM_LEN);
+	return 0;
+}
+
+void schedule_bat_ogm(struct hard_iface *hard_iface)
+{
+	struct bat_priv *bat_priv = netdev_priv(hard_iface->soft_iface);
+	struct hard_iface *primary_if;
+	int tt_num_changes = -1;
+
+	if ((hard_iface->if_status == IF_NOT_IN_USE) ||
+	    (hard_iface->if_status == 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 == IF_TO_BE_ACTIVATED)
+		hard_iface->if_status = IF_ACTIVE;
+
+	primary_if = primary_if_get_selected(bat_priv);
+
+	if (hard_iface == primary_if) {
+		/* if at least one change happened */
+		if (atomic_read(&bat_priv->tt_local_changes) > 0) {
+			tt_commit_changes(bat_priv);
+			tt_num_changes = prepare_packet_buffer(bat_priv,
+							       hard_iface);
+		}
+
+		/* if the changes have been sent often enough */
+		if (!atomic_dec_not_zero(&bat_priv->tt_ogm_append_cnt))
+			tt_num_changes = reset_packet_buffer(bat_priv,
+							     hard_iface);
+	}
+
+	if (primary_if)
+		hardif_free_ref(primary_if);
+
+	bat_priv->bat_algo_ops->bat_ogm_schedule(hard_iface, tt_num_changes);
+}
+
+static void forw_packet_free(struct forw_packet *forw_packet)
+{
+	if (forw_packet->skb)
+		kfree_skb(forw_packet->skb);
+	if (forw_packet->if_incoming)
+		hardif_free_ref(forw_packet->if_incoming);
+	kfree(forw_packet);
+}
+
+static void _add_bcast_packet_to_list(struct bat_priv *bat_priv,
+				      struct 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 */
+	INIT_DELAYED_WORK(&forw_packet->delayed_work,
+			  send_outstanding_bcast_packet);
+	queue_delayed_work(bat_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 add_bcast_packet_to_list(struct bat_priv *bat_priv,
+			     const struct sk_buff *skb, unsigned long delay)
+{
+	struct hard_iface *primary_if = NULL;
+	struct forw_packet *forw_packet;
+	struct bcast_packet *bcast_packet;
+	struct sk_buff *newskb;
+
+	if (!atomic_dec_not_zero(&bat_priv->bcast_queue_left)) {
+		bat_dbg(DBG_BATMAN, bat_priv, "bcast packet queue full\n");
+		goto out;
+	}
+
+	primary_if = 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 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;
+
+	_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)
+		hardif_free_ref(primary_if);
+	return NETDEV_TX_BUSY;
+}
+
+static void send_outstanding_bcast_packet(struct work_struct *work)
+{
+	struct hard_iface *hard_iface;
+	struct delayed_work *delayed_work =
+		container_of(work, struct delayed_work, work);
+	struct forw_packet *forw_packet =
+		container_of(delayed_work, struct forw_packet, delayed_work);
+	struct sk_buff *skb1;
+	struct net_device *soft_iface = forw_packet->if_incoming->soft_iface;
+	struct bat_priv *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) == MESH_DEACTIVATING)
+		goto out;
+
+	/* rebroadcast packet */
+	rcu_read_lock();
+	list_for_each_entry_rcu(hard_iface, &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)
+			send_skb_packet(skb1, hard_iface, broadcast_addr);
+	}
+	rcu_read_unlock();
+
+	forw_packet->num_packets++;
+
+	/* if we still have some more bcasts to send */
+	if (forw_packet->num_packets < 3) {
+		_add_bcast_packet_to_list(bat_priv, forw_packet,
+					  ((5 * HZ) / 1000));
+		return;
+	}
+
+out:
+	forw_packet_free(forw_packet);
+	atomic_inc(&bat_priv->bcast_queue_left);
+}
+
+void send_outstanding_bat_ogm_packet(struct work_struct *work)
+{
+	struct delayed_work *delayed_work =
+		container_of(work, struct delayed_work, work);
+	struct forw_packet *forw_packet =
+		container_of(delayed_work, struct forw_packet, delayed_work);
+	struct bat_priv *bat_priv;
+
+	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) == 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)
+		schedule_bat_ogm(forw_packet->if_incoming);
+
+out:
+	/* don't count own packet */
+	if (!forw_packet->own)
+		atomic_inc(&bat_priv->batman_queue_left);
+
+	forw_packet_free(forw_packet);
+}
+
+void purge_outstanding_packets(struct bat_priv *bat_priv,
+			       const struct hard_iface *hard_iface)
+{
+	struct forw_packet *forw_packet;
+	struct hlist_node *tmp_node, *safe_tmp_node;
+	bool pending;
+
+	if (hard_iface)
+		bat_dbg(DBG_BATMAN, bat_priv,
+			"purge_outstanding_packets(): %s\n",
+			hard_iface->net_dev->name);
+	else
+		bat_dbg(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, tmp_node, 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);
+
+		/**
+		 * 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);
+			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, tmp_node, 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);
+			forw_packet_free(forw_packet);
+		}
+	}
+	spin_unlock_bh(&bat_priv->forw_bat_list_lock);
+}