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![Antonio Quartulli](/assets/img/avatar_default.png)
On some architectures ether_addr_copy() is slightly faster than memcpy() therefore use the former when possible. Signed-off-by: Antonio Quartulli <antonio@meshcoding.com> Signed-off-by: Marek Lindner <mareklindner@neomailbox.ch>
1936 lines
57 KiB
C
1936 lines
57 KiB
C
/* Copyright (C) 2012-2014 B.A.T.M.A.N. contributors:
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*
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* Martin Hundebøll, Jeppe Ledet-Pedersen
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*
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* This program is free software; you can redistribute it and/or
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* modify it under the terms of version 2 of the GNU General Public
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* License as published by the Free Software Foundation.
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*
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* This program is distributed in the hope that it will be useful, but
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* WITHOUT ANY WARRANTY; without even the implied warranty of
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* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
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* General Public License for more details.
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*
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* You should have received a copy of the GNU General Public License
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* along with this program; if not, see <http://www.gnu.org/licenses/>.
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*/
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#include <linux/debugfs.h>
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#include "main.h"
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#include "hash.h"
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#include "network-coding.h"
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#include "send.h"
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#include "originator.h"
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#include "hard-interface.h"
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#include "routing.h"
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static struct lock_class_key batadv_nc_coding_hash_lock_class_key;
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static struct lock_class_key batadv_nc_decoding_hash_lock_class_key;
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static void batadv_nc_worker(struct work_struct *work);
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static int batadv_nc_recv_coded_packet(struct sk_buff *skb,
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struct batadv_hard_iface *recv_if);
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/**
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* batadv_nc_init - one-time initialization for network coding
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*/
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int __init batadv_nc_init(void)
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{
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int ret;
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/* Register our packet type */
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ret = batadv_recv_handler_register(BATADV_CODED,
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batadv_nc_recv_coded_packet);
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return ret;
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}
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/**
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* batadv_nc_start_timer - initialise the nc periodic worker
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* @bat_priv: the bat priv with all the soft interface information
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*/
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static void batadv_nc_start_timer(struct batadv_priv *bat_priv)
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{
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queue_delayed_work(batadv_event_workqueue, &bat_priv->nc.work,
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msecs_to_jiffies(10));
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}
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/**
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* batadv_nc_tvlv_container_update - update the network coding tvlv container
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* after network coding setting change
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* @bat_priv: the bat priv with all the soft interface information
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*/
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static void batadv_nc_tvlv_container_update(struct batadv_priv *bat_priv)
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{
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char nc_mode;
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nc_mode = atomic_read(&bat_priv->network_coding);
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switch (nc_mode) {
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case 0:
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batadv_tvlv_container_unregister(bat_priv, BATADV_TVLV_NC, 1);
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break;
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case 1:
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batadv_tvlv_container_register(bat_priv, BATADV_TVLV_NC, 1,
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NULL, 0);
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break;
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}
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}
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/**
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* batadv_nc_status_update - update the network coding tvlv container after
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* network coding setting change
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* @net_dev: the soft interface net device
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*/
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void batadv_nc_status_update(struct net_device *net_dev)
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{
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struct batadv_priv *bat_priv = netdev_priv(net_dev);
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batadv_nc_tvlv_container_update(bat_priv);
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}
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/**
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* batadv_nc_tvlv_ogm_handler_v1 - process incoming nc tvlv container
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* @bat_priv: the bat priv with all the soft interface information
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* @orig: the orig_node of the ogm
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* @flags: flags indicating the tvlv state (see batadv_tvlv_handler_flags)
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* @tvlv_value: tvlv buffer containing the gateway data
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* @tvlv_value_len: tvlv buffer length
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*/
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static void batadv_nc_tvlv_ogm_handler_v1(struct batadv_priv *bat_priv,
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struct batadv_orig_node *orig,
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uint8_t flags,
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void *tvlv_value,
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uint16_t tvlv_value_len)
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{
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if (flags & BATADV_TVLV_HANDLER_OGM_CIFNOTFND)
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orig->capabilities &= ~BATADV_ORIG_CAPA_HAS_NC;
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else
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orig->capabilities |= BATADV_ORIG_CAPA_HAS_NC;
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}
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/**
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* batadv_nc_mesh_init - initialise coding hash table and start house keeping
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* @bat_priv: the bat priv with all the soft interface information
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*/
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int batadv_nc_mesh_init(struct batadv_priv *bat_priv)
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{
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bat_priv->nc.timestamp_fwd_flush = jiffies;
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bat_priv->nc.timestamp_sniffed_purge = jiffies;
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if (bat_priv->nc.coding_hash || bat_priv->nc.decoding_hash)
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return 0;
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bat_priv->nc.coding_hash = batadv_hash_new(128);
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if (!bat_priv->nc.coding_hash)
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goto err;
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batadv_hash_set_lock_class(bat_priv->nc.coding_hash,
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&batadv_nc_coding_hash_lock_class_key);
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bat_priv->nc.decoding_hash = batadv_hash_new(128);
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if (!bat_priv->nc.decoding_hash)
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goto err;
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batadv_hash_set_lock_class(bat_priv->nc.coding_hash,
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&batadv_nc_decoding_hash_lock_class_key);
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INIT_DELAYED_WORK(&bat_priv->nc.work, batadv_nc_worker);
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batadv_nc_start_timer(bat_priv);
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batadv_tvlv_handler_register(bat_priv, batadv_nc_tvlv_ogm_handler_v1,
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NULL, BATADV_TVLV_NC, 1,
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BATADV_TVLV_HANDLER_OGM_CIFNOTFND);
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batadv_nc_tvlv_container_update(bat_priv);
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return 0;
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err:
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return -ENOMEM;
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}
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/**
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* batadv_nc_init_bat_priv - initialise the nc specific bat_priv variables
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* @bat_priv: the bat priv with all the soft interface information
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*/
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void batadv_nc_init_bat_priv(struct batadv_priv *bat_priv)
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{
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atomic_set(&bat_priv->network_coding, 1);
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bat_priv->nc.min_tq = 200;
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bat_priv->nc.max_fwd_delay = 10;
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bat_priv->nc.max_buffer_time = 200;
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}
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/**
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* batadv_nc_init_orig - initialise the nc fields of an orig_node
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* @orig_node: the orig_node which is going to be initialised
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*/
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void batadv_nc_init_orig(struct batadv_orig_node *orig_node)
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{
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INIT_LIST_HEAD(&orig_node->in_coding_list);
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INIT_LIST_HEAD(&orig_node->out_coding_list);
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spin_lock_init(&orig_node->in_coding_list_lock);
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spin_lock_init(&orig_node->out_coding_list_lock);
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}
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/**
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* batadv_nc_node_free_rcu - rcu callback to free an nc node and remove
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* its refcount on the orig_node
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* @rcu: rcu pointer of the nc node
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*/
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static void batadv_nc_node_free_rcu(struct rcu_head *rcu)
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{
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struct batadv_nc_node *nc_node;
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nc_node = container_of(rcu, struct batadv_nc_node, rcu);
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batadv_orig_node_free_ref(nc_node->orig_node);
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kfree(nc_node);
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}
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/**
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* batadv_nc_node_free_ref - decrements the nc node refcounter and possibly
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* frees it
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* @nc_node: the nc node to free
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*/
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static void batadv_nc_node_free_ref(struct batadv_nc_node *nc_node)
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{
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if (atomic_dec_and_test(&nc_node->refcount))
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call_rcu(&nc_node->rcu, batadv_nc_node_free_rcu);
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}
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/**
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* batadv_nc_path_free_ref - decrements the nc path refcounter and possibly
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* frees it
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* @nc_path: the nc node to free
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*/
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static void batadv_nc_path_free_ref(struct batadv_nc_path *nc_path)
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{
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if (atomic_dec_and_test(&nc_path->refcount))
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kfree_rcu(nc_path, rcu);
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}
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/**
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* batadv_nc_packet_free - frees nc packet
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* @nc_packet: the nc packet to free
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*/
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static void batadv_nc_packet_free(struct batadv_nc_packet *nc_packet)
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{
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if (nc_packet->skb)
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kfree_skb(nc_packet->skb);
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batadv_nc_path_free_ref(nc_packet->nc_path);
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kfree(nc_packet);
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}
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/**
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* batadv_nc_to_purge_nc_node - checks whether an nc node has to be purged
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* @bat_priv: the bat priv with all the soft interface information
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* @nc_node: the nc node to check
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*
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* Returns true if the entry has to be purged now, false otherwise
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*/
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static bool batadv_nc_to_purge_nc_node(struct batadv_priv *bat_priv,
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struct batadv_nc_node *nc_node)
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{
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if (atomic_read(&bat_priv->mesh_state) != BATADV_MESH_ACTIVE)
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return true;
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return batadv_has_timed_out(nc_node->last_seen, BATADV_NC_NODE_TIMEOUT);
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}
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/**
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* batadv_nc_to_purge_nc_path_coding - checks whether an nc path has timed out
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* @bat_priv: the bat priv with all the soft interface information
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* @nc_path: the nc path to check
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*
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* Returns true if the entry has to be purged now, false otherwise
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*/
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static bool batadv_nc_to_purge_nc_path_coding(struct batadv_priv *bat_priv,
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struct batadv_nc_path *nc_path)
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{
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if (atomic_read(&bat_priv->mesh_state) != BATADV_MESH_ACTIVE)
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return true;
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/* purge the path when no packets has been added for 10 times the
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* max_fwd_delay time
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*/
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return batadv_has_timed_out(nc_path->last_valid,
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bat_priv->nc.max_fwd_delay * 10);
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}
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/**
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* batadv_nc_to_purge_nc_path_decoding - checks whether an nc path has timed out
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* @bat_priv: the bat priv with all the soft interface information
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* @nc_path: the nc path to check
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*
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* Returns true if the entry has to be purged now, false otherwise
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*/
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static bool batadv_nc_to_purge_nc_path_decoding(struct batadv_priv *bat_priv,
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struct batadv_nc_path *nc_path)
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{
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if (atomic_read(&bat_priv->mesh_state) != BATADV_MESH_ACTIVE)
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return true;
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/* purge the path when no packets has been added for 10 times the
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* max_buffer time
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*/
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return batadv_has_timed_out(nc_path->last_valid,
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bat_priv->nc.max_buffer_time*10);
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}
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/**
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* batadv_nc_purge_orig_nc_nodes - go through list of nc nodes and purge stale
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* entries
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* @bat_priv: the bat priv with all the soft interface information
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* @list: list of nc nodes
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* @lock: nc node list lock
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* @to_purge: function in charge to decide whether an entry has to be purged or
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* not. This function takes the nc node as argument and has to return
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* a boolean value: true if the entry has to be deleted, false
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* otherwise
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*/
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static void
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batadv_nc_purge_orig_nc_nodes(struct batadv_priv *bat_priv,
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struct list_head *list,
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spinlock_t *lock,
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bool (*to_purge)(struct batadv_priv *,
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struct batadv_nc_node *))
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{
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struct batadv_nc_node *nc_node, *nc_node_tmp;
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/* For each nc_node in list */
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spin_lock_bh(lock);
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list_for_each_entry_safe(nc_node, nc_node_tmp, list, list) {
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/* if an helper function has been passed as parameter,
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* ask it if the entry has to be purged or not
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*/
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if (to_purge && !to_purge(bat_priv, nc_node))
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continue;
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batadv_dbg(BATADV_DBG_NC, bat_priv,
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"Removing nc_node %pM -> %pM\n",
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nc_node->addr, nc_node->orig_node->orig);
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list_del_rcu(&nc_node->list);
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batadv_nc_node_free_ref(nc_node);
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}
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spin_unlock_bh(lock);
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}
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/**
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* batadv_nc_purge_orig - purges all nc node data attached of the given
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* originator
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* @bat_priv: the bat priv with all the soft interface information
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* @orig_node: orig_node with the nc node entries to be purged
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* @to_purge: function in charge to decide whether an entry has to be purged or
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* not. This function takes the nc node as argument and has to return
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* a boolean value: true is the entry has to be deleted, false
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* otherwise
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*/
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void batadv_nc_purge_orig(struct batadv_priv *bat_priv,
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struct batadv_orig_node *orig_node,
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bool (*to_purge)(struct batadv_priv *,
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struct batadv_nc_node *))
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{
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/* Check ingoing nc_node's of this orig_node */
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batadv_nc_purge_orig_nc_nodes(bat_priv, &orig_node->in_coding_list,
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&orig_node->in_coding_list_lock,
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to_purge);
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/* Check outgoing nc_node's of this orig_node */
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batadv_nc_purge_orig_nc_nodes(bat_priv, &orig_node->out_coding_list,
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&orig_node->out_coding_list_lock,
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to_purge);
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}
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/**
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* batadv_nc_purge_orig_hash - traverse entire originator hash to check if they
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* have timed out nc nodes
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* @bat_priv: the bat priv with all the soft interface information
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*/
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static void batadv_nc_purge_orig_hash(struct batadv_priv *bat_priv)
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{
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struct batadv_hashtable *hash = bat_priv->orig_hash;
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struct hlist_head *head;
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struct batadv_orig_node *orig_node;
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uint32_t i;
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if (!hash)
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return;
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/* For each orig_node */
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for (i = 0; i < hash->size; i++) {
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head = &hash->table[i];
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rcu_read_lock();
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hlist_for_each_entry_rcu(orig_node, head, hash_entry)
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batadv_nc_purge_orig(bat_priv, orig_node,
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batadv_nc_to_purge_nc_node);
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rcu_read_unlock();
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}
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}
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/**
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* batadv_nc_purge_paths - traverse all nc paths part of the hash and remove
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* unused ones
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* @bat_priv: the bat priv with all the soft interface information
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* @hash: hash table containing the nc paths to check
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* @to_purge: function in charge to decide whether an entry has to be purged or
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* not. This function takes the nc node as argument and has to return
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* a boolean value: true is the entry has to be deleted, false
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* otherwise
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*/
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static void batadv_nc_purge_paths(struct batadv_priv *bat_priv,
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struct batadv_hashtable *hash,
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bool (*to_purge)(struct batadv_priv *,
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struct batadv_nc_path *))
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{
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struct hlist_head *head;
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struct hlist_node *node_tmp;
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struct batadv_nc_path *nc_path;
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spinlock_t *lock; /* Protects lists in hash */
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uint32_t i;
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for (i = 0; i < hash->size; i++) {
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head = &hash->table[i];
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lock = &hash->list_locks[i];
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/* For each nc_path in this bin */
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spin_lock_bh(lock);
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hlist_for_each_entry_safe(nc_path, node_tmp, head, hash_entry) {
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/* if an helper function has been passed as parameter,
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* ask it if the entry has to be purged or not
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*/
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if (to_purge && !to_purge(bat_priv, nc_path))
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continue;
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/* purging an non-empty nc_path should never happen, but
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* is observed under high CPU load. Delay the purging
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* until next iteration to allow the packet_list to be
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* emptied first.
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*/
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if (!unlikely(list_empty(&nc_path->packet_list))) {
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net_ratelimited_function(printk,
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KERN_WARNING
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"Skipping free of non-empty nc_path (%pM -> %pM)!\n",
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nc_path->prev_hop,
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nc_path->next_hop);
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continue;
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}
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/* nc_path is unused, so remove it */
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batadv_dbg(BATADV_DBG_NC, bat_priv,
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"Remove nc_path %pM -> %pM\n",
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nc_path->prev_hop, nc_path->next_hop);
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hlist_del_rcu(&nc_path->hash_entry);
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batadv_nc_path_free_ref(nc_path);
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}
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spin_unlock_bh(lock);
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}
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}
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/**
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* batadv_nc_hash_key_gen - computes the nc_path hash key
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* @key: buffer to hold the final hash key
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* @src: source ethernet mac address going into the hash key
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* @dst: destination ethernet mac address going into the hash key
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*/
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static void batadv_nc_hash_key_gen(struct batadv_nc_path *key, const char *src,
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const char *dst)
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{
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memcpy(key->prev_hop, src, sizeof(key->prev_hop));
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memcpy(key->next_hop, dst, sizeof(key->next_hop));
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}
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/**
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* batadv_nc_hash_choose - compute the hash value for an nc path
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* @data: data to hash
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* @size: size of the hash table
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*
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* Returns the selected index in the hash table for the given data.
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*/
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static uint32_t batadv_nc_hash_choose(const void *data, uint32_t size)
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{
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const struct batadv_nc_path *nc_path = data;
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uint32_t hash = 0;
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hash = batadv_hash_bytes(hash, &nc_path->prev_hop,
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sizeof(nc_path->prev_hop));
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hash = batadv_hash_bytes(hash, &nc_path->next_hop,
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sizeof(nc_path->next_hop));
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hash += (hash << 3);
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hash ^= (hash >> 11);
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hash += (hash << 15);
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return hash % size;
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}
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|
/**
|
|
* batadv_nc_hash_compare - comparing function used in the network coding hash
|
|
* tables
|
|
* @node: node in the local table
|
|
* @data2: second object to compare the node to
|
|
*
|
|
* Returns 1 if the two entry are the same, 0 otherwise
|
|
*/
|
|
static int batadv_nc_hash_compare(const struct hlist_node *node,
|
|
const void *data2)
|
|
{
|
|
const struct batadv_nc_path *nc_path1, *nc_path2;
|
|
|
|
nc_path1 = container_of(node, struct batadv_nc_path, hash_entry);
|
|
nc_path2 = data2;
|
|
|
|
/* Return 1 if the two keys are identical */
|
|
if (memcmp(nc_path1->prev_hop, nc_path2->prev_hop,
|
|
sizeof(nc_path1->prev_hop)) != 0)
|
|
return 0;
|
|
|
|
if (memcmp(nc_path1->next_hop, nc_path2->next_hop,
|
|
sizeof(nc_path1->next_hop)) != 0)
|
|
return 0;
|
|
|
|
return 1;
|
|
}
|
|
|
|
/**
|
|
* batadv_nc_hash_find - search for an existing nc path and return it
|
|
* @hash: hash table containing the nc path
|
|
* @data: search key
|
|
*
|
|
* Returns the nc_path if found, NULL otherwise.
|
|
*/
|
|
static struct batadv_nc_path *
|
|
batadv_nc_hash_find(struct batadv_hashtable *hash,
|
|
void *data)
|
|
{
|
|
struct hlist_head *head;
|
|
struct batadv_nc_path *nc_path, *nc_path_tmp = NULL;
|
|
int index;
|
|
|
|
if (!hash)
|
|
return NULL;
|
|
|
|
index = batadv_nc_hash_choose(data, hash->size);
|
|
head = &hash->table[index];
|
|
|
|
rcu_read_lock();
|
|
hlist_for_each_entry_rcu(nc_path, head, hash_entry) {
|
|
if (!batadv_nc_hash_compare(&nc_path->hash_entry, data))
|
|
continue;
|
|
|
|
if (!atomic_inc_not_zero(&nc_path->refcount))
|
|
continue;
|
|
|
|
nc_path_tmp = nc_path;
|
|
break;
|
|
}
|
|
rcu_read_unlock();
|
|
|
|
return nc_path_tmp;
|
|
}
|
|
|
|
/**
|
|
* batadv_nc_send_packet - send non-coded packet and free nc_packet struct
|
|
* @nc_packet: the nc packet to send
|
|
*/
|
|
static void batadv_nc_send_packet(struct batadv_nc_packet *nc_packet)
|
|
{
|
|
batadv_send_skb_packet(nc_packet->skb,
|
|
nc_packet->neigh_node->if_incoming,
|
|
nc_packet->nc_path->next_hop);
|
|
nc_packet->skb = NULL;
|
|
batadv_nc_packet_free(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
|
|
* @nc_packet: the nc packet to be checked
|
|
*
|
|
* Checks whether the given nc packet has hit its forward timeout. If so, the
|
|
* packet is no longer delayed, immediately sent 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_fwd_flush(struct batadv_priv *bat_priv,
|
|
struct batadv_nc_path *nc_path,
|
|
struct batadv_nc_packet *nc_packet)
|
|
{
|
|
unsigned long timeout = bat_priv->nc.max_fwd_delay;
|
|
|
|
/* 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))
|
|
return false;
|
|
|
|
/* Send packet */
|
|
batadv_inc_counter(bat_priv, BATADV_CNT_FORWARD);
|
|
batadv_add_counter(bat_priv, BATADV_CNT_FORWARD_BYTES,
|
|
nc_packet->skb->len + ETH_HLEN);
|
|
list_del(&nc_packet->list);
|
|
batadv_nc_send_packet(nc_packet);
|
|
|
|
return true;
|
|
}
|
|
|
|
/**
|
|
* batadv_nc_process_nc_paths - traverse given nc packet pool and free timed out
|
|
* nc packets
|
|
* @bat_priv: the bat priv with all the soft interface information
|
|
* @hash: to be processed hash table
|
|
* @process_fn: Function called to process given nc packet. Should return true
|
|
* to encourage this function to proceed with the next packet.
|
|
* Otherwise the rest of the current queue is skipped.
|
|
*/
|
|
static void
|
|
batadv_nc_process_nc_paths(struct batadv_priv *bat_priv,
|
|
struct batadv_hashtable *hash,
|
|
bool (*process_fn)(struct batadv_priv *,
|
|
struct batadv_nc_path *,
|
|
struct batadv_nc_packet *))
|
|
{
|
|
struct hlist_head *head;
|
|
struct batadv_nc_packet *nc_packet, *nc_packet_tmp;
|
|
struct batadv_nc_path *nc_path;
|
|
bool ret;
|
|
int i;
|
|
|
|
if (!hash)
|
|
return;
|
|
|
|
/* Loop hash table bins */
|
|
for (i = 0; i < hash->size; i++) {
|
|
head = &hash->table[i];
|
|
|
|
/* Loop coding paths */
|
|
rcu_read_lock();
|
|
hlist_for_each_entry_rcu(nc_path, head, hash_entry) {
|
|
/* Loop packets */
|
|
spin_lock_bh(&nc_path->packet_list_lock);
|
|
list_for_each_entry_safe(nc_packet, nc_packet_tmp,
|
|
&nc_path->packet_list, list) {
|
|
ret = process_fn(bat_priv, nc_path, nc_packet);
|
|
if (!ret)
|
|
break;
|
|
}
|
|
spin_unlock_bh(&nc_path->packet_list_lock);
|
|
}
|
|
rcu_read_unlock();
|
|
}
|
|
}
|
|
|
|
/**
|
|
* batadv_nc_worker - periodic task for house keeping related to network coding
|
|
* @work: kernel work struct
|
|
*/
|
|
static void batadv_nc_worker(struct work_struct *work)
|
|
{
|
|
struct delayed_work *delayed_work;
|
|
struct batadv_priv_nc *priv_nc;
|
|
struct batadv_priv *bat_priv;
|
|
unsigned long timeout;
|
|
|
|
delayed_work = container_of(work, struct delayed_work, work);
|
|
priv_nc = container_of(delayed_work, struct batadv_priv_nc, work);
|
|
bat_priv = container_of(priv_nc, struct batadv_priv, nc);
|
|
|
|
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;
|
|
|
|
if (batadv_has_timed_out(bat_priv->nc.timestamp_fwd_flush, timeout)) {
|
|
batadv_nc_process_nc_paths(bat_priv, bat_priv->nc.coding_hash,
|
|
batadv_nc_fwd_flush);
|
|
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);
|
|
}
|
|
|
|
/**
|
|
* batadv_can_nc_with_orig - checks whether the given orig node is suitable for
|
|
* coding or not
|
|
* @bat_priv: the bat priv with all the soft interface information
|
|
* @orig_node: neighboring orig node which may be used as nc candidate
|
|
* @ogm_packet: incoming ogm packet also used for the checks
|
|
*
|
|
* Returns true if:
|
|
* 1) The OGM must have the most recent sequence number.
|
|
* 2) The TTL must be decremented by one and only one.
|
|
* 3) The OGM must be received from the first hop from orig_node.
|
|
* 4) The TQ value of the OGM must be above bat_priv->nc.min_tq.
|
|
*/
|
|
static bool batadv_can_nc_with_orig(struct batadv_priv *bat_priv,
|
|
struct batadv_orig_node *orig_node,
|
|
struct batadv_ogm_packet *ogm_packet)
|
|
{
|
|
struct batadv_orig_ifinfo *orig_ifinfo;
|
|
uint32_t last_real_seqno;
|
|
uint8_t last_ttl;
|
|
|
|
orig_ifinfo = batadv_orig_ifinfo_get(orig_node, BATADV_IF_DEFAULT);
|
|
if (!orig_ifinfo)
|
|
return false;
|
|
|
|
last_ttl = orig_ifinfo->last_ttl;
|
|
last_real_seqno = orig_ifinfo->last_real_seqno;
|
|
batadv_orig_ifinfo_free_ref(orig_ifinfo);
|
|
|
|
if (last_real_seqno != ntohl(ogm_packet->seqno))
|
|
return false;
|
|
if (last_ttl != ogm_packet->ttl + 1)
|
|
return false;
|
|
if (!batadv_compare_eth(ogm_packet->orig, ogm_packet->prev_sender))
|
|
return false;
|
|
if (ogm_packet->tq < bat_priv->nc.min_tq)
|
|
return false;
|
|
|
|
return true;
|
|
}
|
|
|
|
/**
|
|
* batadv_nc_find_nc_node - search for an existing nc node and return it
|
|
* @orig_node: orig node originating the ogm packet
|
|
* @orig_neigh_node: neighboring orig node from which we received the ogm packet
|
|
* (can be equal to orig_node)
|
|
* @in_coding: traverse incoming or outgoing network coding list
|
|
*
|
|
* Returns the nc_node if found, NULL otherwise.
|
|
*/
|
|
static struct batadv_nc_node
|
|
*batadv_nc_find_nc_node(struct batadv_orig_node *orig_node,
|
|
struct batadv_orig_node *orig_neigh_node,
|
|
bool in_coding)
|
|
{
|
|
struct batadv_nc_node *nc_node, *nc_node_out = NULL;
|
|
struct list_head *list;
|
|
|
|
if (in_coding)
|
|
list = &orig_neigh_node->in_coding_list;
|
|
else
|
|
list = &orig_neigh_node->out_coding_list;
|
|
|
|
/* Traverse list of nc_nodes to orig_node */
|
|
rcu_read_lock();
|
|
list_for_each_entry_rcu(nc_node, list, list) {
|
|
if (!batadv_compare_eth(nc_node->addr, orig_node->orig))
|
|
continue;
|
|
|
|
if (!atomic_inc_not_zero(&nc_node->refcount))
|
|
continue;
|
|
|
|
/* Found a match */
|
|
nc_node_out = nc_node;
|
|
break;
|
|
}
|
|
rcu_read_unlock();
|
|
|
|
return nc_node_out;
|
|
}
|
|
|
|
/**
|
|
* batadv_nc_get_nc_node - retrieves an nc node or creates the entry if it was
|
|
* not found
|
|
* @bat_priv: the bat priv with all the soft interface information
|
|
* @orig_node: orig node originating the ogm packet
|
|
* @orig_neigh_node: neighboring orig node from which we received the ogm packet
|
|
* (can be equal to orig_node)
|
|
* @in_coding: traverse incoming or outgoing network coding list
|
|
*
|
|
* Returns the nc_node if found or created, NULL in case of an error.
|
|
*/
|
|
static struct batadv_nc_node
|
|
*batadv_nc_get_nc_node(struct batadv_priv *bat_priv,
|
|
struct batadv_orig_node *orig_node,
|
|
struct batadv_orig_node *orig_neigh_node,
|
|
bool in_coding)
|
|
{
|
|
struct batadv_nc_node *nc_node;
|
|
spinlock_t *lock; /* Used to lock list selected by "int in_coding" */
|
|
struct list_head *list;
|
|
|
|
/* Check if nc_node is already added */
|
|
nc_node = batadv_nc_find_nc_node(orig_node, orig_neigh_node, in_coding);
|
|
|
|
/* Node found */
|
|
if (nc_node)
|
|
return nc_node;
|
|
|
|
nc_node = kzalloc(sizeof(*nc_node), GFP_ATOMIC);
|
|
if (!nc_node)
|
|
return NULL;
|
|
|
|
if (!atomic_inc_not_zero(&orig_neigh_node->refcount))
|
|
goto free;
|
|
|
|
/* Initialize nc_node */
|
|
INIT_LIST_HEAD(&nc_node->list);
|
|
ether_addr_copy(nc_node->addr, orig_node->orig);
|
|
nc_node->orig_node = orig_neigh_node;
|
|
atomic_set(&nc_node->refcount, 2);
|
|
|
|
/* Select ingoing or outgoing coding node */
|
|
if (in_coding) {
|
|
lock = &orig_neigh_node->in_coding_list_lock;
|
|
list = &orig_neigh_node->in_coding_list;
|
|
} else {
|
|
lock = &orig_neigh_node->out_coding_list_lock;
|
|
list = &orig_neigh_node->out_coding_list;
|
|
}
|
|
|
|
batadv_dbg(BATADV_DBG_NC, bat_priv, "Adding nc_node %pM -> %pM\n",
|
|
nc_node->addr, nc_node->orig_node->orig);
|
|
|
|
/* Add nc_node to orig_node */
|
|
spin_lock_bh(lock);
|
|
list_add_tail_rcu(&nc_node->list, list);
|
|
spin_unlock_bh(lock);
|
|
|
|
return nc_node;
|
|
|
|
free:
|
|
kfree(nc_node);
|
|
return NULL;
|
|
}
|
|
|
|
/**
|
|
* batadv_nc_update_nc_node - updates stored incoming and outgoing nc node structs
|
|
* (best called on incoming OGMs)
|
|
* @bat_priv: the bat priv with all the soft interface information
|
|
* @orig_node: orig node originating the ogm packet
|
|
* @orig_neigh_node: neighboring orig node from which we received the ogm packet
|
|
* (can be equal to orig_node)
|
|
* @ogm_packet: incoming ogm packet
|
|
* @is_single_hop_neigh: orig_node is a single hop neighbor
|
|
*/
|
|
void batadv_nc_update_nc_node(struct batadv_priv *bat_priv,
|
|
struct batadv_orig_node *orig_node,
|
|
struct batadv_orig_node *orig_neigh_node,
|
|
struct batadv_ogm_packet *ogm_packet,
|
|
int is_single_hop_neigh)
|
|
{
|
|
struct batadv_nc_node *in_nc_node = NULL, *out_nc_node = NULL;
|
|
|
|
/* Check if network coding is enabled */
|
|
if (!atomic_read(&bat_priv->network_coding))
|
|
goto out;
|
|
|
|
/* check if orig node is network coding enabled */
|
|
if (!(orig_node->capabilities & BATADV_ORIG_CAPA_HAS_NC))
|
|
goto out;
|
|
|
|
/* accept ogms from 'good' neighbors and single hop neighbors */
|
|
if (!batadv_can_nc_with_orig(bat_priv, orig_node, ogm_packet) &&
|
|
!is_single_hop_neigh)
|
|
goto out;
|
|
|
|
/* Add orig_node as in_nc_node on hop */
|
|
in_nc_node = batadv_nc_get_nc_node(bat_priv, orig_node,
|
|
orig_neigh_node, true);
|
|
if (!in_nc_node)
|
|
goto out;
|
|
|
|
in_nc_node->last_seen = jiffies;
|
|
|
|
/* Add hop as out_nc_node on orig_node */
|
|
out_nc_node = batadv_nc_get_nc_node(bat_priv, orig_neigh_node,
|
|
orig_node, false);
|
|
if (!out_nc_node)
|
|
goto out;
|
|
|
|
out_nc_node->last_seen = jiffies;
|
|
|
|
out:
|
|
if (in_nc_node)
|
|
batadv_nc_node_free_ref(in_nc_node);
|
|
if (out_nc_node)
|
|
batadv_nc_node_free_ref(out_nc_node);
|
|
}
|
|
|
|
/**
|
|
* batadv_nc_get_path - get existing nc_path or allocate a new one
|
|
* @bat_priv: the bat priv with all the soft interface information
|
|
* @hash: hash table containing the nc path
|
|
* @src: ethernet source address - first half of the nc path search key
|
|
* @dst: ethernet destination address - second half of the nc path search key
|
|
*
|
|
* Returns pointer to nc_path if the path was found or created, returns NULL
|
|
* on error.
|
|
*/
|
|
static struct batadv_nc_path *batadv_nc_get_path(struct batadv_priv *bat_priv,
|
|
struct batadv_hashtable *hash,
|
|
uint8_t *src,
|
|
uint8_t *dst)
|
|
{
|
|
int hash_added;
|
|
struct batadv_nc_path *nc_path, nc_path_key;
|
|
|
|
batadv_nc_hash_key_gen(&nc_path_key, src, dst);
|
|
|
|
/* Search for existing nc_path */
|
|
nc_path = batadv_nc_hash_find(hash, (void *)&nc_path_key);
|
|
|
|
if (nc_path) {
|
|
/* Set timestamp to delay removal of nc_path */
|
|
nc_path->last_valid = jiffies;
|
|
return nc_path;
|
|
}
|
|
|
|
/* No existing nc_path was found; create a new */
|
|
nc_path = kzalloc(sizeof(*nc_path), GFP_ATOMIC);
|
|
|
|
if (!nc_path)
|
|
return NULL;
|
|
|
|
/* Initialize nc_path */
|
|
INIT_LIST_HEAD(&nc_path->packet_list);
|
|
spin_lock_init(&nc_path->packet_list_lock);
|
|
atomic_set(&nc_path->refcount, 2);
|
|
nc_path->last_valid = jiffies;
|
|
ether_addr_copy(nc_path->next_hop, dst);
|
|
ether_addr_copy(nc_path->prev_hop, src);
|
|
|
|
batadv_dbg(BATADV_DBG_NC, bat_priv, "Adding nc_path %pM -> %pM\n",
|
|
nc_path->prev_hop,
|
|
nc_path->next_hop);
|
|
|
|
/* Add nc_path to hash table */
|
|
hash_added = batadv_hash_add(hash, batadv_nc_hash_compare,
|
|
batadv_nc_hash_choose, &nc_path_key,
|
|
&nc_path->hash_entry);
|
|
|
|
if (hash_added < 0) {
|
|
kfree(nc_path);
|
|
return NULL;
|
|
}
|
|
|
|
return nc_path;
|
|
}
|
|
|
|
/**
|
|
* batadv_nc_random_weight_tq - scale the receivers TQ-value to avoid unfair
|
|
* selection of a receiver with slightly lower TQ than the other
|
|
* @tq: to be weighted tq value
|
|
*/
|
|
static uint8_t batadv_nc_random_weight_tq(uint8_t tq)
|
|
{
|
|
uint8_t rand_val, rand_tq;
|
|
|
|
get_random_bytes(&rand_val, sizeof(rand_val));
|
|
|
|
/* randomize the estimated packet loss (max TQ - estimated TQ) */
|
|
rand_tq = rand_val * (BATADV_TQ_MAX_VALUE - tq);
|
|
|
|
/* normalize the randomized packet loss */
|
|
rand_tq /= BATADV_TQ_MAX_VALUE;
|
|
|
|
/* convert to (randomized) estimated tq again */
|
|
return BATADV_TQ_MAX_VALUE - rand_tq;
|
|
}
|
|
|
|
/**
|
|
* batadv_nc_memxor - XOR destination with source
|
|
* @dst: byte array to XOR into
|
|
* @src: byte array to XOR from
|
|
* @len: length of destination array
|
|
*/
|
|
static void batadv_nc_memxor(char *dst, const char *src, unsigned int len)
|
|
{
|
|
unsigned int i;
|
|
|
|
for (i = 0; i < len; ++i)
|
|
dst[i] ^= src[i];
|
|
}
|
|
|
|
/**
|
|
* batadv_nc_code_packets - code a received unicast_packet with an nc packet
|
|
* into a coded_packet and send it
|
|
* @bat_priv: the bat priv with all the soft interface information
|
|
* @skb: data skb to forward
|
|
* @ethhdr: pointer to the ethernet header inside the skb
|
|
* @nc_packet: structure containing the packet to the skb can be coded with
|
|
* @neigh_node: next hop to forward packet to
|
|
*
|
|
* Returns true if both packets are consumed, false otherwise.
|
|
*/
|
|
static bool batadv_nc_code_packets(struct batadv_priv *bat_priv,
|
|
struct sk_buff *skb,
|
|
struct ethhdr *ethhdr,
|
|
struct batadv_nc_packet *nc_packet,
|
|
struct batadv_neigh_node *neigh_node)
|
|
{
|
|
uint8_t tq_weighted_neigh, tq_weighted_coding, tq_tmp;
|
|
struct sk_buff *skb_dest, *skb_src;
|
|
struct batadv_unicast_packet *packet1;
|
|
struct batadv_unicast_packet *packet2;
|
|
struct batadv_coded_packet *coded_packet;
|
|
struct batadv_neigh_node *neigh_tmp, *router_neigh;
|
|
struct batadv_neigh_node *router_coding = NULL;
|
|
struct batadv_neigh_ifinfo *router_neigh_ifinfo = NULL;
|
|
struct batadv_neigh_ifinfo *router_coding_ifinfo = NULL;
|
|
uint8_t *first_source, *first_dest, *second_source, *second_dest;
|
|
__be32 packet_id1, packet_id2;
|
|
size_t count;
|
|
bool res = false;
|
|
int coding_len;
|
|
int unicast_size = sizeof(*packet1);
|
|
int coded_size = sizeof(*coded_packet);
|
|
int header_add = coded_size - unicast_size;
|
|
|
|
/* TODO: do we need to consider the outgoing interface for
|
|
* coded packets?
|
|
*/
|
|
router_neigh = batadv_orig_router_get(neigh_node->orig_node,
|
|
BATADV_IF_DEFAULT);
|
|
if (!router_neigh)
|
|
goto out;
|
|
|
|
router_neigh_ifinfo = batadv_neigh_ifinfo_get(router_neigh,
|
|
BATADV_IF_DEFAULT);
|
|
if (!router_neigh_ifinfo)
|
|
goto out;
|
|
|
|
neigh_tmp = nc_packet->neigh_node;
|
|
router_coding = batadv_orig_router_get(neigh_tmp->orig_node,
|
|
BATADV_IF_DEFAULT);
|
|
if (!router_coding)
|
|
goto out;
|
|
|
|
router_coding_ifinfo = batadv_neigh_ifinfo_get(router_coding,
|
|
BATADV_IF_DEFAULT);
|
|
if (!router_coding_ifinfo)
|
|
goto out;
|
|
|
|
tq_tmp = router_neigh_ifinfo->bat_iv.tq_avg;
|
|
tq_weighted_neigh = batadv_nc_random_weight_tq(tq_tmp);
|
|
tq_tmp = router_coding_ifinfo->bat_iv.tq_avg;
|
|
tq_weighted_coding = batadv_nc_random_weight_tq(tq_tmp);
|
|
|
|
/* Select one destination for the MAC-header dst-field based on
|
|
* weighted TQ-values.
|
|
*/
|
|
if (tq_weighted_neigh >= tq_weighted_coding) {
|
|
/* Destination from nc_packet is selected for MAC-header */
|
|
first_dest = nc_packet->nc_path->next_hop;
|
|
first_source = nc_packet->nc_path->prev_hop;
|
|
second_dest = neigh_node->addr;
|
|
second_source = ethhdr->h_source;
|
|
packet1 = (struct batadv_unicast_packet *)nc_packet->skb->data;
|
|
packet2 = (struct batadv_unicast_packet *)skb->data;
|
|
packet_id1 = nc_packet->packet_id;
|
|
packet_id2 = batadv_skb_crc32(skb,
|
|
skb->data + sizeof(*packet2));
|
|
} else {
|
|
/* Destination for skb is selected for MAC-header */
|
|
first_dest = neigh_node->addr;
|
|
first_source = ethhdr->h_source;
|
|
second_dest = nc_packet->nc_path->next_hop;
|
|
second_source = nc_packet->nc_path->prev_hop;
|
|
packet1 = (struct batadv_unicast_packet *)skb->data;
|
|
packet2 = (struct batadv_unicast_packet *)nc_packet->skb->data;
|
|
packet_id1 = batadv_skb_crc32(skb,
|
|
skb->data + sizeof(*packet1));
|
|
packet_id2 = nc_packet->packet_id;
|
|
}
|
|
|
|
/* Instead of zero padding the smallest data buffer, we
|
|
* code into the largest.
|
|
*/
|
|
if (skb->len <= nc_packet->skb->len) {
|
|
skb_dest = nc_packet->skb;
|
|
skb_src = skb;
|
|
} else {
|
|
skb_dest = skb;
|
|
skb_src = nc_packet->skb;
|
|
}
|
|
|
|
/* coding_len is used when decoding the packet shorter packet */
|
|
coding_len = skb_src->len - unicast_size;
|
|
|
|
if (skb_linearize(skb_dest) < 0 || skb_linearize(skb_src) < 0)
|
|
goto out;
|
|
|
|
skb_push(skb_dest, header_add);
|
|
|
|
coded_packet = (struct batadv_coded_packet *)skb_dest->data;
|
|
skb_reset_mac_header(skb_dest);
|
|
|
|
coded_packet->packet_type = BATADV_CODED;
|
|
coded_packet->version = BATADV_COMPAT_VERSION;
|
|
coded_packet->ttl = packet1->ttl;
|
|
|
|
/* Info about first unicast packet */
|
|
ether_addr_copy(coded_packet->first_source, first_source);
|
|
ether_addr_copy(coded_packet->first_orig_dest, packet1->dest);
|
|
coded_packet->first_crc = packet_id1;
|
|
coded_packet->first_ttvn = packet1->ttvn;
|
|
|
|
/* Info about second unicast packet */
|
|
ether_addr_copy(coded_packet->second_dest, second_dest);
|
|
ether_addr_copy(coded_packet->second_source, second_source);
|
|
ether_addr_copy(coded_packet->second_orig_dest, packet2->dest);
|
|
coded_packet->second_crc = packet_id2;
|
|
coded_packet->second_ttl = packet2->ttl;
|
|
coded_packet->second_ttvn = packet2->ttvn;
|
|
coded_packet->coded_len = htons(coding_len);
|
|
|
|
/* This is where the magic happens: Code skb_src into skb_dest */
|
|
batadv_nc_memxor(skb_dest->data + coded_size,
|
|
skb_src->data + unicast_size, coding_len);
|
|
|
|
/* Update counters accordingly */
|
|
if (BATADV_SKB_CB(skb_src)->decoded &&
|
|
BATADV_SKB_CB(skb_dest)->decoded) {
|
|
/* Both packets are recoded */
|
|
count = skb_src->len + ETH_HLEN;
|
|
count += skb_dest->len + ETH_HLEN;
|
|
batadv_add_counter(bat_priv, BATADV_CNT_NC_RECODE, 2);
|
|
batadv_add_counter(bat_priv, BATADV_CNT_NC_RECODE_BYTES, count);
|
|
} else if (!BATADV_SKB_CB(skb_src)->decoded &&
|
|
!BATADV_SKB_CB(skb_dest)->decoded) {
|
|
/* Both packets are newly coded */
|
|
count = skb_src->len + ETH_HLEN;
|
|
count += skb_dest->len + ETH_HLEN;
|
|
batadv_add_counter(bat_priv, BATADV_CNT_NC_CODE, 2);
|
|
batadv_add_counter(bat_priv, BATADV_CNT_NC_CODE_BYTES, count);
|
|
} else if (BATADV_SKB_CB(skb_src)->decoded &&
|
|
!BATADV_SKB_CB(skb_dest)->decoded) {
|
|
/* skb_src recoded and skb_dest is newly coded */
|
|
batadv_inc_counter(bat_priv, BATADV_CNT_NC_RECODE);
|
|
batadv_add_counter(bat_priv, BATADV_CNT_NC_RECODE_BYTES,
|
|
skb_src->len + ETH_HLEN);
|
|
batadv_inc_counter(bat_priv, BATADV_CNT_NC_CODE);
|
|
batadv_add_counter(bat_priv, BATADV_CNT_NC_CODE_BYTES,
|
|
skb_dest->len + ETH_HLEN);
|
|
} else if (!BATADV_SKB_CB(skb_src)->decoded &&
|
|
BATADV_SKB_CB(skb_dest)->decoded) {
|
|
/* skb_src is newly coded and skb_dest is recoded */
|
|
batadv_inc_counter(bat_priv, BATADV_CNT_NC_CODE);
|
|
batadv_add_counter(bat_priv, BATADV_CNT_NC_CODE_BYTES,
|
|
skb_src->len + ETH_HLEN);
|
|
batadv_inc_counter(bat_priv, BATADV_CNT_NC_RECODE);
|
|
batadv_add_counter(bat_priv, BATADV_CNT_NC_RECODE_BYTES,
|
|
skb_dest->len + ETH_HLEN);
|
|
}
|
|
|
|
/* skb_src is now coded into skb_dest, so free it */
|
|
kfree_skb(skb_src);
|
|
|
|
/* avoid duplicate free of skb from nc_packet */
|
|
nc_packet->skb = NULL;
|
|
batadv_nc_packet_free(nc_packet);
|
|
|
|
/* Send the coded packet and return true */
|
|
batadv_send_skb_packet(skb_dest, neigh_node->if_incoming, first_dest);
|
|
res = true;
|
|
out:
|
|
if (router_neigh)
|
|
batadv_neigh_node_free_ref(router_neigh);
|
|
if (router_coding)
|
|
batadv_neigh_node_free_ref(router_coding);
|
|
if (router_neigh_ifinfo)
|
|
batadv_neigh_ifinfo_free_ref(router_neigh_ifinfo);
|
|
if (router_coding_ifinfo)
|
|
batadv_neigh_ifinfo_free_ref(router_coding_ifinfo);
|
|
return res;
|
|
}
|
|
|
|
/**
|
|
* batadv_nc_skb_coding_possible - true if a decoded skb is available at dst.
|
|
* @skb: data skb to forward
|
|
* @dst: destination mac address of the other skb to code with
|
|
* @src: source mac address of skb
|
|
*
|
|
* Whenever we network code a packet we have to check whether we received it in
|
|
* a network coded form. If so, we may not be able to use it for coding because
|
|
* some neighbors may also have received (overheard) the packet in the network
|
|
* coded form without being able to decode it. It is hard to know which of the
|
|
* neighboring nodes was able to decode the packet, therefore we can only
|
|
* re-code the packet if the source of the previous encoded packet is involved.
|
|
* Since the source encoded the packet we can be certain it has all necessary
|
|
* decode information.
|
|
*
|
|
* Returns true if coding of a decoded packet is allowed.
|
|
*/
|
|
static bool batadv_nc_skb_coding_possible(struct sk_buff *skb,
|
|
uint8_t *dst, uint8_t *src)
|
|
{
|
|
if (BATADV_SKB_CB(skb)->decoded && !batadv_compare_eth(dst, src))
|
|
return false;
|
|
else
|
|
return true;
|
|
}
|
|
|
|
/**
|
|
* batadv_nc_path_search - Find the coding path matching in_nc_node and
|
|
* out_nc_node to retrieve a buffered packet that can be used for coding.
|
|
* @bat_priv: the bat priv with all the soft interface information
|
|
* @in_nc_node: pointer to skb next hop's neighbor nc node
|
|
* @out_nc_node: pointer to skb source's neighbor nc node
|
|
* @skb: data skb to forward
|
|
* @eth_dst: next hop mac address of skb
|
|
*
|
|
* Returns true if coding of a decoded skb is allowed.
|
|
*/
|
|
static struct batadv_nc_packet *
|
|
batadv_nc_path_search(struct batadv_priv *bat_priv,
|
|
struct batadv_nc_node *in_nc_node,
|
|
struct batadv_nc_node *out_nc_node,
|
|
struct sk_buff *skb,
|
|
uint8_t *eth_dst)
|
|
{
|
|
struct batadv_nc_path *nc_path, nc_path_key;
|
|
struct batadv_nc_packet *nc_packet_out = NULL;
|
|
struct batadv_nc_packet *nc_packet, *nc_packet_tmp;
|
|
struct batadv_hashtable *hash = bat_priv->nc.coding_hash;
|
|
int idx;
|
|
|
|
if (!hash)
|
|
return NULL;
|
|
|
|
/* Create almost path key */
|
|
batadv_nc_hash_key_gen(&nc_path_key, in_nc_node->addr,
|
|
out_nc_node->addr);
|
|
idx = batadv_nc_hash_choose(&nc_path_key, hash->size);
|
|
|
|
/* Check for coding opportunities in this nc_path */
|
|
rcu_read_lock();
|
|
hlist_for_each_entry_rcu(nc_path, &hash->table[idx], hash_entry) {
|
|
if (!batadv_compare_eth(nc_path->prev_hop, in_nc_node->addr))
|
|
continue;
|
|
|
|
if (!batadv_compare_eth(nc_path->next_hop, out_nc_node->addr))
|
|
continue;
|
|
|
|
spin_lock_bh(&nc_path->packet_list_lock);
|
|
if (list_empty(&nc_path->packet_list)) {
|
|
spin_unlock_bh(&nc_path->packet_list_lock);
|
|
continue;
|
|
}
|
|
|
|
list_for_each_entry_safe(nc_packet, nc_packet_tmp,
|
|
&nc_path->packet_list, list) {
|
|
if (!batadv_nc_skb_coding_possible(nc_packet->skb,
|
|
eth_dst,
|
|
in_nc_node->addr))
|
|
continue;
|
|
|
|
/* Coding opportunity is found! */
|
|
list_del(&nc_packet->list);
|
|
nc_packet_out = nc_packet;
|
|
break;
|
|
}
|
|
|
|
spin_unlock_bh(&nc_path->packet_list_lock);
|
|
break;
|
|
}
|
|
rcu_read_unlock();
|
|
|
|
return nc_packet_out;
|
|
}
|
|
|
|
/**
|
|
* batadv_nc_skb_src_search - Loops through the list of neighoring nodes of the
|
|
* skb's sender (may be equal to the originator).
|
|
* @bat_priv: the bat priv with all the soft interface information
|
|
* @skb: data skb to forward
|
|
* @eth_dst: next hop mac address of skb
|
|
* @eth_src: source mac address of skb
|
|
* @in_nc_node: pointer to skb next hop's neighbor nc node
|
|
*
|
|
* Returns an nc packet if a suitable coding packet was found, NULL otherwise.
|
|
*/
|
|
static struct batadv_nc_packet *
|
|
batadv_nc_skb_src_search(struct batadv_priv *bat_priv,
|
|
struct sk_buff *skb,
|
|
uint8_t *eth_dst,
|
|
uint8_t *eth_src,
|
|
struct batadv_nc_node *in_nc_node)
|
|
{
|
|
struct batadv_orig_node *orig_node;
|
|
struct batadv_nc_node *out_nc_node;
|
|
struct batadv_nc_packet *nc_packet = NULL;
|
|
|
|
orig_node = batadv_orig_hash_find(bat_priv, eth_src);
|
|
if (!orig_node)
|
|
return NULL;
|
|
|
|
rcu_read_lock();
|
|
list_for_each_entry_rcu(out_nc_node,
|
|
&orig_node->out_coding_list, list) {
|
|
/* Check if the skb is decoded and if recoding is possible */
|
|
if (!batadv_nc_skb_coding_possible(skb,
|
|
out_nc_node->addr, eth_src))
|
|
continue;
|
|
|
|
/* Search for an opportunity in this nc_path */
|
|
nc_packet = batadv_nc_path_search(bat_priv, in_nc_node,
|
|
out_nc_node, skb, eth_dst);
|
|
if (nc_packet)
|
|
break;
|
|
}
|
|
rcu_read_unlock();
|
|
|
|
batadv_orig_node_free_ref(orig_node);
|
|
return nc_packet;
|
|
}
|
|
|
|
/**
|
|
* 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 = eth_hdr(skb);
|
|
ether_addr_copy(ethhdr->h_source, ethhdr->h_dest);
|
|
ether_addr_copy(ethhdr->h_dest, eth_dst_new);
|
|
|
|
/* 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
|
|
* @ethhdr: pointer to the ethernet header inside the skb
|
|
*
|
|
* Loops through list of neighboring nodes the next hop has a good connection to
|
|
* (receives OGMs with a sufficient quality). We need to find a neighbor of our
|
|
* next hop that potentially sent a packet which our next hop also received
|
|
* (overheard) and has stored for later decoding.
|
|
*
|
|
* Returns true if the skb was consumed (encoded packet sent) or false otherwise
|
|
*/
|
|
static bool batadv_nc_skb_dst_search(struct sk_buff *skb,
|
|
struct batadv_neigh_node *neigh_node,
|
|
struct ethhdr *ethhdr)
|
|
{
|
|
struct net_device *netdev = neigh_node->if_incoming->soft_iface;
|
|
struct batadv_priv *bat_priv = netdev_priv(netdev);
|
|
struct batadv_orig_node *orig_node = neigh_node->orig_node;
|
|
struct batadv_nc_node *nc_node;
|
|
struct batadv_nc_packet *nc_packet = NULL;
|
|
|
|
rcu_read_lock();
|
|
list_for_each_entry_rcu(nc_node, &orig_node->in_coding_list, list) {
|
|
/* Search for coding opportunity with this in_nc_node */
|
|
nc_packet = batadv_nc_skb_src_search(bat_priv, skb,
|
|
neigh_node->addr,
|
|
ethhdr->h_source, nc_node);
|
|
|
|
/* Opportunity was found, so stop searching */
|
|
if (nc_packet)
|
|
break;
|
|
}
|
|
rcu_read_unlock();
|
|
|
|
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))
|
|
return true;
|
|
|
|
/* out of mem ? Coding failed - we have to free the buffered packet
|
|
* to avoid memleaks. The skb passed as argument will be dealt with
|
|
* by the calling function.
|
|
*/
|
|
batadv_nc_send_packet(nc_packet);
|
|
return false;
|
|
}
|
|
|
|
/**
|
|
* batadv_nc_skb_add_to_path - buffer skb for later encoding / decoding
|
|
* @skb: skb to add to path
|
|
* @nc_path: path to add skb to
|
|
* @neigh_node: next hop to forward packet to
|
|
* @packet_id: checksum to identify packet
|
|
*
|
|
* Returns true if the packet was buffered or false in case of an error.
|
|
*/
|
|
static bool batadv_nc_skb_add_to_path(struct sk_buff *skb,
|
|
struct batadv_nc_path *nc_path,
|
|
struct batadv_neigh_node *neigh_node,
|
|
__be32 packet_id)
|
|
{
|
|
struct batadv_nc_packet *nc_packet;
|
|
|
|
nc_packet = kzalloc(sizeof(*nc_packet), GFP_ATOMIC);
|
|
if (!nc_packet)
|
|
return false;
|
|
|
|
/* Initialize nc_packet */
|
|
nc_packet->timestamp = jiffies;
|
|
nc_packet->packet_id = packet_id;
|
|
nc_packet->skb = skb;
|
|
nc_packet->neigh_node = neigh_node;
|
|
nc_packet->nc_path = nc_path;
|
|
|
|
/* Add coding packet to list */
|
|
spin_lock_bh(&nc_path->packet_list_lock);
|
|
list_add_tail(&nc_packet->list, &nc_path->packet_list);
|
|
spin_unlock_bh(&nc_path->packet_list_lock);
|
|
|
|
return true;
|
|
}
|
|
|
|
/**
|
|
* batadv_nc_skb_forward - try to code a packet or add it to the coding packet
|
|
* buffer
|
|
* @skb: data skb to forward
|
|
* @neigh_node: next hop to forward packet to
|
|
*
|
|
* Returns true if the skb was consumed (encoded packet sent) or false otherwise
|
|
*/
|
|
bool batadv_nc_skb_forward(struct sk_buff *skb,
|
|
struct batadv_neigh_node *neigh_node)
|
|
{
|
|
const struct net_device *netdev = neigh_node->if_incoming->soft_iface;
|
|
struct batadv_priv *bat_priv = netdev_priv(netdev);
|
|
struct batadv_unicast_packet *packet;
|
|
struct batadv_nc_path *nc_path;
|
|
struct ethhdr *ethhdr = eth_hdr(skb);
|
|
__be32 packet_id;
|
|
u8 *payload;
|
|
|
|
/* Check if network coding is enabled */
|
|
if (!atomic_read(&bat_priv->network_coding))
|
|
goto out;
|
|
|
|
/* We only handle unicast packets */
|
|
payload = skb_network_header(skb);
|
|
packet = (struct batadv_unicast_packet *)payload;
|
|
if (packet->packet_type != BATADV_UNICAST)
|
|
goto out;
|
|
|
|
/* Try to find a coding opportunity and send the skb if one is found */
|
|
if (batadv_nc_skb_dst_search(skb, neigh_node, ethhdr))
|
|
return true;
|
|
|
|
/* Find or create a nc_path for this src-dst pair */
|
|
nc_path = batadv_nc_get_path(bat_priv,
|
|
bat_priv->nc.coding_hash,
|
|
ethhdr->h_source,
|
|
neigh_node->addr);
|
|
|
|
if (!nc_path)
|
|
goto out;
|
|
|
|
/* Add skb to nc_path */
|
|
packet_id = batadv_skb_crc32(skb, payload + sizeof(*packet));
|
|
if (!batadv_nc_skb_add_to_path(skb, nc_path, neigh_node, packet_id))
|
|
goto free_nc_path;
|
|
|
|
/* Packet is consumed */
|
|
return true;
|
|
|
|
free_nc_path:
|
|
batadv_nc_path_free_ref(nc_path);
|
|
out:
|
|
/* Packet is not consumed */
|
|
return false;
|
|
}
|
|
|
|
/**
|
|
* 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 = eth_hdr(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->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 = eth_hdr(skb);
|
|
|
|
if (batadv_is_my_mac(bat_priv, 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_skb_decode_packet - decode given skb using the decode data stored
|
|
* in nc_packet
|
|
* @bat_priv: the bat priv with all the soft interface information
|
|
* @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 batadv_priv *bat_priv, 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;
|
|
int err;
|
|
|
|
/* Save headers temporarily */
|
|
memcpy(&coded_packet_tmp, skb->data, sizeof(coded_packet_tmp));
|
|
memcpy(ðhdr_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 = eth_hdr(skb);
|
|
*ethhdr = ethhdr_tmp;
|
|
|
|
/* Select the correct unicast header information based on the location
|
|
* of our mac address in the coded_packet header
|
|
*/
|
|
if (batadv_is_my_mac(bat_priv, 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
|
|
*/
|
|
ether_addr_copy(ethhdr->h_dest, coded_packet_tmp.second_dest);
|
|
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.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) {
|
|
err = pskb_trim_rcsum(skb, coding_len + h_size);
|
|
if (err)
|
|
return NULL;
|
|
}
|
|
|
|
/* Create decoded unicast packet */
|
|
unicast_packet = (struct batadv_unicast_packet *)skb->data;
|
|
unicast_packet->packet_type = BATADV_UNICAST;
|
|
unicast_packet->version = BATADV_COMPAT_VERSION;
|
|
unicast_packet->ttl = ttl;
|
|
ether_addr_copy(unicast_packet->dest, orig_dest);
|
|
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 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(bat_priv, 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, &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 = eth_hdr(skb);
|
|
|
|
/* Verify frame is destined for us */
|
|
if (!batadv_is_my_mac(bat_priv, ethhdr->h_dest) &&
|
|
!batadv_is_my_mac(bat_priv, coded_packet->second_dest))
|
|
return NET_RX_DROP;
|
|
|
|
/* Update stat counter */
|
|
if (batadv_is_my_mac(bat_priv, 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(bat_priv, 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_mesh_free - clean up network coding memory
|
|
* @bat_priv: the bat priv with all the soft interface information
|
|
*/
|
|
void batadv_nc_mesh_free(struct batadv_priv *bat_priv)
|
|
{
|
|
batadv_tvlv_container_unregister(bat_priv, BATADV_TVLV_NC, 1);
|
|
batadv_tvlv_handler_unregister(bat_priv, BATADV_TVLV_NC, 1);
|
|
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);
|
|
}
|
|
|
|
/**
|
|
* batadv_nc_nodes_seq_print_text - print the nc node information
|
|
* @seq: seq file to print on
|
|
* @offset: not used
|
|
*/
|
|
int batadv_nc_nodes_seq_print_text(struct seq_file *seq, void *offset)
|
|
{
|
|
struct net_device *net_dev = (struct net_device *)seq->private;
|
|
struct batadv_priv *bat_priv = netdev_priv(net_dev);
|
|
struct batadv_hashtable *hash = bat_priv->orig_hash;
|
|
struct batadv_hard_iface *primary_if;
|
|
struct hlist_head *head;
|
|
struct batadv_orig_node *orig_node;
|
|
struct batadv_nc_node *nc_node;
|
|
int i;
|
|
|
|
primary_if = batadv_seq_print_text_primary_if_get(seq);
|
|
if (!primary_if)
|
|
goto out;
|
|
|
|
/* Traverse list of originators */
|
|
for (i = 0; i < hash->size; i++) {
|
|
head = &hash->table[i];
|
|
|
|
/* For each orig_node in this bin */
|
|
rcu_read_lock();
|
|
hlist_for_each_entry_rcu(orig_node, head, hash_entry) {
|
|
/* no need to print the orig node if it does not have
|
|
* network coding neighbors
|
|
*/
|
|
if (list_empty(&orig_node->in_coding_list) &&
|
|
list_empty(&orig_node->out_coding_list))
|
|
continue;
|
|
|
|
seq_printf(seq, "Node: %pM\n", orig_node->orig);
|
|
|
|
seq_puts(seq, " Ingoing: ");
|
|
/* For each in_nc_node to this orig_node */
|
|
list_for_each_entry_rcu(nc_node,
|
|
&orig_node->in_coding_list,
|
|
list)
|
|
seq_printf(seq, "%pM ",
|
|
nc_node->addr);
|
|
seq_puts(seq, "\n");
|
|
|
|
seq_puts(seq, " Outgoing: ");
|
|
/* For out_nc_node to this orig_node */
|
|
list_for_each_entry_rcu(nc_node,
|
|
&orig_node->out_coding_list,
|
|
list)
|
|
seq_printf(seq, "%pM ",
|
|
nc_node->addr);
|
|
seq_puts(seq, "\n\n");
|
|
}
|
|
rcu_read_unlock();
|
|
}
|
|
|
|
out:
|
|
if (primary_if)
|
|
batadv_hardif_free_ref(primary_if);
|
|
return 0;
|
|
}
|
|
|
|
/**
|
|
* batadv_nc_init_debugfs - create nc folder and related files in debugfs
|
|
* @bat_priv: the bat priv with all the soft interface information
|
|
*/
|
|
int batadv_nc_init_debugfs(struct batadv_priv *bat_priv)
|
|
{
|
|
struct dentry *nc_dir, *file;
|
|
|
|
nc_dir = debugfs_create_dir("nc", bat_priv->debug_dir);
|
|
if (!nc_dir)
|
|
goto out;
|
|
|
|
file = debugfs_create_u8("min_tq", S_IRUGO | S_IWUSR, nc_dir,
|
|
&bat_priv->nc.min_tq);
|
|
if (!file)
|
|
goto out;
|
|
|
|
file = debugfs_create_u32("max_fwd_delay", S_IRUGO | S_IWUSR, nc_dir,
|
|
&bat_priv->nc.max_fwd_delay);
|
|
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:
|
|
return -ENOMEM;
|
|
}
|