/* 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 = eth_hdr(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 NET_XMIT_SUCCESS on success, NET_XMIT_DROP on failure, or
* NET_XMIT_POLICED if the skb is buffered for later transmit.
*/
int 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;
int ret = NET_XMIT_DROP;
/* batadv_find_router() increases neigh_nodes refcount if found. */
neigh_node = batadv_find_router(bat_priv, orig_node, recv_if);
if (!neigh_node)
return ret;
/* try to network code the packet, if it is received on an interface
* (i.e. being forwarded). If the packet originates from this node or if
* network coding fails, then send the packet as usual.
*/
if (recv_if && batadv_nc_skb_forward(skb, neigh_node)) {
ret = NET_XMIT_POLICED;
} else {
batadv_send_skb_packet(skb, neigh_node->if_incoming,
neigh_node->addr);
ret = NET_XMIT_SUCCESS;
}
batadv_neigh_node_free_ref(neigh_node);
return ret;
}
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)
{
/* 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;
if (forw_packet->num_packets >= hard_iface->num_bcasts)
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 < BATADV_NUM_BCASTS_MAX) {
_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);
}
