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1875 lines
56 KiB
1875 lines
56 KiB
// SPDX-License-Identifier: GPL-2.0 |
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/* Copyright (C) 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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|
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#include "network-coding.h" |
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#include "main.h" |
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|
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#include <linux/atomic.h> |
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#include <linux/bitops.h> |
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#include <linux/byteorder/generic.h> |
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#include <linux/compiler.h> |
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#include <linux/errno.h> |
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#include <linux/etherdevice.h> |
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#include <linux/gfp.h> |
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#include <linux/if_ether.h> |
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#include <linux/if_packet.h> |
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#include <linux/init.h> |
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#include <linux/jhash.h> |
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#include <linux/jiffies.h> |
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#include <linux/kernel.h> |
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#include <linux/kref.h> |
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#include <linux/list.h> |
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#include <linux/lockdep.h> |
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#include <linux/net.h> |
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#include <linux/netdevice.h> |
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#include <linux/prandom.h> |
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#include <linux/printk.h> |
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#include <linux/rculist.h> |
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#include <linux/rcupdate.h> |
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#include <linux/skbuff.h> |
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#include <linux/slab.h> |
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#include <linux/spinlock.h> |
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#include <linux/stddef.h> |
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#include <linux/string.h> |
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#include <linux/workqueue.h> |
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#include <uapi/linux/batadv_packet.h> |
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|
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#include "hash.h" |
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#include "log.h" |
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#include "originator.h" |
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#include "routing.h" |
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#include "send.h" |
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#include "tvlv.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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/** |
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* batadv_nc_init() - one-time initialization for network coding |
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* |
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* Return: 0 on success or negative error number in case of failure |
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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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/** |
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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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u8 flags, |
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void *tvlv_value, u16 tvlv_value_len) |
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{ |
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if (flags & BATADV_TVLV_HANDLER_OGM_CIFNOTFND) |
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clear_bit(BATADV_ORIG_CAPA_HAS_NC, &orig->capabilities); |
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else |
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set_bit(BATADV_ORIG_CAPA_HAS_NC, &orig->capabilities); |
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} |
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/** |
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* batadv_nc_mesh_init() - initialise coding hash table and start housekeeping |
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* @bat_priv: the bat priv with all the soft interface information |
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* |
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* Return: 0 on success or negative error number in case of failure |
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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.decoding_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, 0); |
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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_release() - release nc_node from lists and queue for free |
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* after rcu grace period |
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* @ref: kref pointer of the nc_node |
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*/ |
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static void batadv_nc_node_release(struct kref *ref) |
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{ |
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struct batadv_nc_node *nc_node; |
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nc_node = container_of(ref, struct batadv_nc_node, refcount); |
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batadv_orig_node_put(nc_node->orig_node); |
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kfree_rcu(nc_node, rcu); |
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} |
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/** |
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* batadv_nc_node_put() - decrement the nc_node refcounter and possibly |
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* release it |
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* @nc_node: nc_node to be free'd |
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*/ |
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static void batadv_nc_node_put(struct batadv_nc_node *nc_node) |
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{ |
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if (!nc_node) |
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return; |
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kref_put(&nc_node->refcount, batadv_nc_node_release); |
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} |
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/** |
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* batadv_nc_path_release() - release nc_path from lists and queue for free |
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* after rcu grace period |
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* @ref: kref pointer of the nc_path |
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*/ |
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static void batadv_nc_path_release(struct kref *ref) |
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{ |
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struct batadv_nc_path *nc_path; |
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nc_path = container_of(ref, struct batadv_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_path_put() - decrement the nc_path refcounter and possibly |
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* release it |
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* @nc_path: nc_path to be free'd |
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*/ |
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static void batadv_nc_path_put(struct batadv_nc_path *nc_path) |
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{ |
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if (!nc_path) |
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return; |
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kref_put(&nc_path->refcount, batadv_nc_path_release); |
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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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* @dropped: whether the packet is freed because is dropped |
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*/ |
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static void batadv_nc_packet_free(struct batadv_nc_packet *nc_packet, |
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bool dropped) |
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{ |
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if (dropped) |
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kfree_skb(nc_packet->skb); |
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else |
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consume_skb(nc_packet->skb); |
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batadv_nc_path_put(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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* Return: 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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* Return: 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 |
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* 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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* Return: 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_put(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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/** |
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* batadv_nc_purge_orig_hash() - traverse entire originator hash to check if |
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* they 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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u32 i; |
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|
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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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|
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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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/** |
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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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u32 i; |
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|
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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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|
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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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|
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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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|
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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_put(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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/** |
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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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* Return: the selected index in the hash table for the given data. |
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*/ |
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static u32 batadv_nc_hash_choose(const void *data, u32 size) |
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{ |
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const struct batadv_nc_path *nc_path = data; |
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u32 hash = 0; |
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|
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hash = jhash(&nc_path->prev_hop, sizeof(nc_path->prev_hop), hash); |
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hash = jhash(&nc_path->next_hop, sizeof(nc_path->next_hop), hash); |
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|
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return hash % size; |
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} |
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|
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/** |
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* batadv_nc_hash_compare() - comparing function used in the network coding hash |
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* tables |
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* @node: node in the local table |
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* @data2: second object to compare the node to |
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* |
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* Return: true if the two entry are the same, false otherwise |
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*/ |
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static bool batadv_nc_hash_compare(const struct hlist_node *node, |
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const void *data2) |
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{ |
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const struct batadv_nc_path *nc_path1, *nc_path2; |
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|
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nc_path1 = container_of(node, struct batadv_nc_path, hash_entry); |
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nc_path2 = data2; |
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|
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/* Return 1 if the two keys are identical */ |
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if (!batadv_compare_eth(nc_path1->prev_hop, nc_path2->prev_hop)) |
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return false; |
|
|
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if (!batadv_compare_eth(nc_path1->next_hop, nc_path2->next_hop)) |
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return false; |
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|
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return true; |
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} |
|
|
|
/** |
|
* batadv_nc_hash_find() - search for an existing nc path and return it |
|
* @hash: hash table containing the nc path |
|
* @data: search key |
|
* |
|
* Return: 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 (!kref_get_unless_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_unicast_skb(nc_packet->skb, nc_packet->neigh_node); |
|
nc_packet->skb = NULL; |
|
batadv_nc_packet_free(nc_packet, false); |
|
} |
|
|
|
/** |
|
* 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. |
|
* |
|
* Return: 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; |
|
|
|
lockdep_assert_held(&nc_path->packet_list_lock); |
|
|
|
/* 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, true); |
|
|
|
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. |
|
* |
|
* Return: 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; |
|
|
|
lockdep_assert_held(&nc_path->packet_list_lock); |
|
|
|
/* 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 housekeeping 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 = to_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 |
|
* |
|
* Return: 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; |
|
u32 last_real_seqno; |
|
u8 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_put(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 |
|
* |
|
* Return: 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 (!kref_get_unless_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 |
|
* |
|
* Return: 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; |
|
|
|
/* 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; |
|
} |
|
|
|
spin_lock_bh(lock); |
|
|
|
/* 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) |
|
goto unlock; |
|
|
|
nc_node = kzalloc(sizeof(*nc_node), GFP_ATOMIC); |
|
if (!nc_node) |
|
goto unlock; |
|
|
|
/* Initialize nc_node */ |
|
INIT_LIST_HEAD(&nc_node->list); |
|
kref_init(&nc_node->refcount); |
|
ether_addr_copy(nc_node->addr, orig_node->orig); |
|
kref_get(&orig_neigh_node->refcount); |
|
nc_node->orig_node = orig_neigh_node; |
|
|
|
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 */ |
|
kref_get(&nc_node->refcount); |
|
list_add_tail_rcu(&nc_node->list, list); |
|
|
|
unlock: |
|
spin_unlock_bh(lock); |
|
|
|
return nc_node; |
|
} |
|
|
|
/** |
|
* 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; |
|
struct batadv_nc_node *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 (!test_bit(BATADV_ORIG_CAPA_HAS_NC, &orig_node->capabilities)) |
|
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: |
|
batadv_nc_node_put(in_nc_node); |
|
batadv_nc_node_put(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 |
|
* |
|
* Return: 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, |
|
u8 *src, |
|
u8 *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); |
|
kref_init(&nc_path->refcount); |
|
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 */ |
|
kref_get(&nc_path->refcount); |
|
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 |
|
* |
|
* Return: scaled tq value |
|
*/ |
|
static u8 batadv_nc_random_weight_tq(u8 tq) |
|
{ |
|
/* randomize the estimated packet loss (max TQ - estimated TQ) */ |
|
u8 rand_tq = prandom_u32_max(BATADV_TQ_MAX_VALUE + 1 - tq); |
|
|
|
/* 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 |
|
* |
|
* Return: 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) |
|
{ |
|
u8 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, *first_dest; |
|
struct batadv_neigh_node *router_coding = NULL, *second_dest; |
|
struct batadv_neigh_ifinfo *router_neigh_ifinfo = NULL; |
|
struct batadv_neigh_ifinfo *router_coding_ifinfo = NULL; |
|
u8 *first_source, *second_source; |
|
__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->neigh_node; |
|
first_source = nc_packet->nc_path->prev_hop; |
|
second_dest = neigh_node; |
|
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; |
|
first_source = ethhdr->h_source; |
|
second_dest = nc_packet->neigh_node; |
|
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->addr); |
|
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 */ |
|
consume_skb(skb_src); |
|
|
|
/* avoid duplicate free of skb from nc_packet */ |
|
nc_packet->skb = NULL; |
|
batadv_nc_packet_free(nc_packet, false); |
|
|
|
/* Send the coded packet and return true */ |
|
batadv_send_unicast_skb(skb_dest, first_dest); |
|
res = true; |
|
out: |
|
batadv_neigh_node_put(router_neigh); |
|
batadv_neigh_node_put(router_coding); |
|
batadv_neigh_ifinfo_put(router_neigh_ifinfo); |
|
batadv_neigh_ifinfo_put(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. |
|
* |
|
* Return: true if coding of a decoded packet is allowed. |
|
*/ |
|
static bool batadv_nc_skb_coding_possible(struct sk_buff *skb, u8 *dst, u8 *src) |
|
{ |
|
if (BATADV_SKB_CB(skb)->decoded && !batadv_compare_eth(dst, src)) |
|
return false; |
|
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 |
|
* |
|
* Return: 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, |
|
u8 *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 neighboring 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 |
|
* |
|
* Return: 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, |
|
u8 *eth_dst, |
|
u8 *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_put(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, |
|
u8 *eth_dst_new) |
|
{ |
|
struct ethhdr *ethhdr; |
|
|
|
/* Copy skb header to change the mac header */ |
|
skb = pskb_copy_for_clone(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 |
|
*/ |
|
consume_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 the 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. |
|
* |
|
* Return: 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 |
|
* |
|
* Return: 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 |
|
* |
|
* Return: 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_put(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_put(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 |
|
* |
|
* Return: 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; |
|
u8 *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, false); |
|
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 |
|
* |
|
* Return: 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; |
|
u8 *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 |
|
* |
|
* Return: NET_RX_SUCCESS if the packet has been consumed or NET_RX_DROP |
|
* otherwise. |
|
*/ |
|
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)) |
|
goto free_skb; |
|
|
|
/* Make sure we can access (and remove) header */ |
|
if (unlikely(!pskb_may_pull(skb, hdr_size))) |
|
goto free_skb; |
|
|
|
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)) |
|
goto free_skb; |
|
|
|
/* 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); |
|
goto free_skb; |
|
} |
|
|
|
/* 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, true); |
|
free_skb: |
|
kfree_skb(skb); |
|
|
|
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); |
|
}
|
|
|