![Sven Eckelmann](/assets/img/avatar_default.png)
Signed-off-by: Sven Eckelmann <sven@narfation.org> Signed-off-by: Antonio Quartulli <ordex@autistici.org>
727 lines
18 KiB
C
727 lines
18 KiB
C
/* Copyright (C) 2009-2012 B.A.T.M.A.N. contributors:
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*
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* Marek Lindner
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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, write to the Free Software
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* Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA
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* 02110-1301, USA
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*/
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#include "main.h"
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#include "sysfs.h"
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#include "gateway_client.h"
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#include "gateway_common.h"
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#include "hard-interface.h"
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#include "originator.h"
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#include "translation-table.h"
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#include "routing.h"
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#include <linux/ip.h>
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#include <linux/ipv6.h>
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#include <linux/udp.h>
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#include <linux/if_vlan.h>
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/* This is the offset of the options field in a dhcp packet starting at
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* the beginning of the dhcp header
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*/
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#define BATADV_DHCP_OPTIONS_OFFSET 240
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#define BATADV_DHCP_REQUEST 3
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static void batadv_gw_node_free_ref(struct batadv_gw_node *gw_node)
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{
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if (atomic_dec_and_test(&gw_node->refcount))
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kfree_rcu(gw_node, rcu);
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}
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static struct batadv_gw_node *
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batadv_gw_get_selected_gw_node(struct batadv_priv *bat_priv)
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{
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struct batadv_gw_node *gw_node;
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rcu_read_lock();
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gw_node = rcu_dereference(bat_priv->gw.curr_gw);
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if (!gw_node)
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goto out;
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if (!atomic_inc_not_zero(&gw_node->refcount))
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gw_node = NULL;
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out:
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rcu_read_unlock();
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return gw_node;
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}
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struct batadv_orig_node *
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batadv_gw_get_selected_orig(struct batadv_priv *bat_priv)
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{
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struct batadv_gw_node *gw_node;
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struct batadv_orig_node *orig_node = NULL;
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gw_node = batadv_gw_get_selected_gw_node(bat_priv);
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if (!gw_node)
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goto out;
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rcu_read_lock();
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orig_node = gw_node->orig_node;
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if (!orig_node)
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goto unlock;
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if (!atomic_inc_not_zero(&orig_node->refcount))
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orig_node = NULL;
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unlock:
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rcu_read_unlock();
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out:
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if (gw_node)
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batadv_gw_node_free_ref(gw_node);
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return orig_node;
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}
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static void batadv_gw_select(struct batadv_priv *bat_priv,
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struct batadv_gw_node *new_gw_node)
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{
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struct batadv_gw_node *curr_gw_node;
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spin_lock_bh(&bat_priv->gw.list_lock);
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if (new_gw_node && !atomic_inc_not_zero(&new_gw_node->refcount))
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new_gw_node = NULL;
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curr_gw_node = rcu_dereference_protected(bat_priv->gw.curr_gw, 1);
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rcu_assign_pointer(bat_priv->gw.curr_gw, new_gw_node);
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if (curr_gw_node)
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batadv_gw_node_free_ref(curr_gw_node);
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spin_unlock_bh(&bat_priv->gw.list_lock);
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}
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void batadv_gw_deselect(struct batadv_priv *bat_priv)
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{
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atomic_set(&bat_priv->gw.reselect, 1);
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}
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static struct batadv_gw_node *
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batadv_gw_get_best_gw_node(struct batadv_priv *bat_priv)
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{
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struct batadv_neigh_node *router;
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struct hlist_node *node;
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struct batadv_gw_node *gw_node, *curr_gw = NULL;
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uint32_t max_gw_factor = 0, tmp_gw_factor = 0;
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uint32_t gw_divisor;
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uint8_t max_tq = 0;
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int down, up;
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uint8_t tq_avg;
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struct batadv_orig_node *orig_node;
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gw_divisor = BATADV_TQ_LOCAL_WINDOW_SIZE * BATADV_TQ_LOCAL_WINDOW_SIZE;
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gw_divisor *= 64;
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rcu_read_lock();
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hlist_for_each_entry_rcu(gw_node, node, &bat_priv->gw.list, list) {
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if (gw_node->deleted)
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continue;
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orig_node = gw_node->orig_node;
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router = batadv_orig_node_get_router(orig_node);
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if (!router)
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continue;
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if (!atomic_inc_not_zero(&gw_node->refcount))
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goto next;
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tq_avg = router->tq_avg;
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switch (atomic_read(&bat_priv->gw_sel_class)) {
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case 1: /* fast connection */
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batadv_gw_bandwidth_to_kbit(orig_node->gw_flags,
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&down, &up);
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tmp_gw_factor = tq_avg * tq_avg * down * 100 * 100;
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tmp_gw_factor /= gw_divisor;
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if ((tmp_gw_factor > max_gw_factor) ||
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((tmp_gw_factor == max_gw_factor) &&
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(tq_avg > max_tq))) {
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if (curr_gw)
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batadv_gw_node_free_ref(curr_gw);
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curr_gw = gw_node;
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atomic_inc(&curr_gw->refcount);
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}
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break;
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default: /* 2: stable connection (use best statistic)
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* 3: fast-switch (use best statistic but change as
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* soon as a better gateway appears)
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* XX: late-switch (use best statistic but change as
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* soon as a better gateway appears which has
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* $routing_class more tq points)
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*/
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if (tq_avg > max_tq) {
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if (curr_gw)
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batadv_gw_node_free_ref(curr_gw);
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curr_gw = gw_node;
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atomic_inc(&curr_gw->refcount);
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}
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break;
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}
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if (tq_avg > max_tq)
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max_tq = tq_avg;
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if (tmp_gw_factor > max_gw_factor)
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max_gw_factor = tmp_gw_factor;
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batadv_gw_node_free_ref(gw_node);
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next:
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batadv_neigh_node_free_ref(router);
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}
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rcu_read_unlock();
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return curr_gw;
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}
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void batadv_gw_election(struct batadv_priv *bat_priv)
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{
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struct batadv_gw_node *curr_gw = NULL, *next_gw = NULL;
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struct batadv_neigh_node *router = NULL;
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char gw_addr[18] = { '\0' };
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/* The batman daemon checks here if we already passed a full originator
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* cycle in order to make sure we don't choose the first gateway we
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* hear about. This check is based on the daemon's uptime which we
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* don't have.
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*/
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if (atomic_read(&bat_priv->gw_mode) != BATADV_GW_MODE_CLIENT)
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goto out;
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curr_gw = batadv_gw_get_selected_gw_node(bat_priv);
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if (!batadv_atomic_dec_not_zero(&bat_priv->gw.reselect) && curr_gw)
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goto out;
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next_gw = batadv_gw_get_best_gw_node(bat_priv);
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if (curr_gw == next_gw)
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goto out;
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if (next_gw) {
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sprintf(gw_addr, "%pM", next_gw->orig_node->orig);
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router = batadv_orig_node_get_router(next_gw->orig_node);
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if (!router) {
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batadv_gw_deselect(bat_priv);
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goto out;
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}
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}
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if ((curr_gw) && (!next_gw)) {
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batadv_dbg(BATADV_DBG_BATMAN, bat_priv,
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"Removing selected gateway - no gateway in range\n");
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batadv_throw_uevent(bat_priv, BATADV_UEV_GW, BATADV_UEV_DEL,
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NULL);
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} else if ((!curr_gw) && (next_gw)) {
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batadv_dbg(BATADV_DBG_BATMAN, bat_priv,
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"Adding route to gateway %pM (gw_flags: %i, tq: %i)\n",
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next_gw->orig_node->orig,
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next_gw->orig_node->gw_flags, router->tq_avg);
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batadv_throw_uevent(bat_priv, BATADV_UEV_GW, BATADV_UEV_ADD,
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gw_addr);
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} else {
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batadv_dbg(BATADV_DBG_BATMAN, bat_priv,
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"Changing route to gateway %pM (gw_flags: %i, tq: %i)\n",
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next_gw->orig_node->orig,
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next_gw->orig_node->gw_flags, router->tq_avg);
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batadv_throw_uevent(bat_priv, BATADV_UEV_GW, BATADV_UEV_CHANGE,
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gw_addr);
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}
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batadv_gw_select(bat_priv, next_gw);
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out:
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if (curr_gw)
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batadv_gw_node_free_ref(curr_gw);
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if (next_gw)
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batadv_gw_node_free_ref(next_gw);
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if (router)
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batadv_neigh_node_free_ref(router);
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}
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void batadv_gw_check_election(struct batadv_priv *bat_priv,
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struct batadv_orig_node *orig_node)
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{
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struct batadv_orig_node *curr_gw_orig;
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struct batadv_neigh_node *router_gw = NULL, *router_orig = NULL;
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uint8_t gw_tq_avg, orig_tq_avg;
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curr_gw_orig = batadv_gw_get_selected_orig(bat_priv);
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if (!curr_gw_orig)
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goto deselect;
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router_gw = batadv_orig_node_get_router(curr_gw_orig);
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if (!router_gw)
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goto deselect;
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/* this node already is the gateway */
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if (curr_gw_orig == orig_node)
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goto out;
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router_orig = batadv_orig_node_get_router(orig_node);
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if (!router_orig)
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goto out;
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gw_tq_avg = router_gw->tq_avg;
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orig_tq_avg = router_orig->tq_avg;
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/* the TQ value has to be better */
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if (orig_tq_avg < gw_tq_avg)
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goto out;
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/* if the routing class is greater than 3 the value tells us how much
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* greater the TQ value of the new gateway must be
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*/
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if ((atomic_read(&bat_priv->gw_sel_class) > 3) &&
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(orig_tq_avg - gw_tq_avg < atomic_read(&bat_priv->gw_sel_class)))
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goto out;
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batadv_dbg(BATADV_DBG_BATMAN, bat_priv,
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"Restarting gateway selection: better gateway found (tq curr: %i, tq new: %i)\n",
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gw_tq_avg, orig_tq_avg);
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deselect:
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batadv_gw_deselect(bat_priv);
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out:
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if (curr_gw_orig)
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batadv_orig_node_free_ref(curr_gw_orig);
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if (router_gw)
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batadv_neigh_node_free_ref(router_gw);
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if (router_orig)
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batadv_neigh_node_free_ref(router_orig);
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return;
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}
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static void batadv_gw_node_add(struct batadv_priv *bat_priv,
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struct batadv_orig_node *orig_node,
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uint8_t new_gwflags)
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{
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struct batadv_gw_node *gw_node;
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int down, up;
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gw_node = kzalloc(sizeof(*gw_node), GFP_ATOMIC);
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if (!gw_node)
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return;
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INIT_HLIST_NODE(&gw_node->list);
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gw_node->orig_node = orig_node;
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atomic_set(&gw_node->refcount, 1);
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spin_lock_bh(&bat_priv->gw.list_lock);
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hlist_add_head_rcu(&gw_node->list, &bat_priv->gw.list);
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spin_unlock_bh(&bat_priv->gw.list_lock);
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batadv_gw_bandwidth_to_kbit(new_gwflags, &down, &up);
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batadv_dbg(BATADV_DBG_BATMAN, bat_priv,
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"Found new gateway %pM -> gw_class: %i - %i%s/%i%s\n",
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orig_node->orig, new_gwflags,
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(down > 2048 ? down / 1024 : down),
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(down > 2048 ? "MBit" : "KBit"),
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(up > 2048 ? up / 1024 : up),
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(up > 2048 ? "MBit" : "KBit"));
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}
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void batadv_gw_node_update(struct batadv_priv *bat_priv,
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struct batadv_orig_node *orig_node,
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uint8_t new_gwflags)
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{
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struct hlist_node *node;
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struct batadv_gw_node *gw_node, *curr_gw;
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/* Note: We don't need a NULL check here, since curr_gw never gets
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* dereferenced. If curr_gw is NULL we also should not exit as we may
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* have this gateway in our list (duplication check!) even though we
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* have no currently selected gateway.
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*/
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curr_gw = batadv_gw_get_selected_gw_node(bat_priv);
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rcu_read_lock();
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hlist_for_each_entry_rcu(gw_node, node, &bat_priv->gw.list, list) {
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if (gw_node->orig_node != orig_node)
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continue;
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batadv_dbg(BATADV_DBG_BATMAN, bat_priv,
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"Gateway class of originator %pM changed from %i to %i\n",
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orig_node->orig, gw_node->orig_node->gw_flags,
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new_gwflags);
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gw_node->deleted = 0;
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if (new_gwflags == BATADV_NO_FLAGS) {
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gw_node->deleted = jiffies;
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batadv_dbg(BATADV_DBG_BATMAN, bat_priv,
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"Gateway %pM removed from gateway list\n",
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orig_node->orig);
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if (gw_node == curr_gw)
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goto deselect;
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}
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goto unlock;
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}
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if (new_gwflags == BATADV_NO_FLAGS)
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goto unlock;
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batadv_gw_node_add(bat_priv, orig_node, new_gwflags);
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goto unlock;
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deselect:
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batadv_gw_deselect(bat_priv);
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unlock:
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rcu_read_unlock();
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if (curr_gw)
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batadv_gw_node_free_ref(curr_gw);
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}
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void batadv_gw_node_delete(struct batadv_priv *bat_priv,
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struct batadv_orig_node *orig_node)
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{
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batadv_gw_node_update(bat_priv, orig_node, 0);
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}
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void batadv_gw_node_purge(struct batadv_priv *bat_priv)
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{
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struct batadv_gw_node *gw_node, *curr_gw;
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struct hlist_node *node, *node_tmp;
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unsigned long timeout = msecs_to_jiffies(2 * BATADV_PURGE_TIMEOUT);
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int do_deselect = 0;
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curr_gw = batadv_gw_get_selected_gw_node(bat_priv);
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spin_lock_bh(&bat_priv->gw.list_lock);
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hlist_for_each_entry_safe(gw_node, node, node_tmp,
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&bat_priv->gw.list, list) {
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if (((!gw_node->deleted) ||
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(time_before(jiffies, gw_node->deleted + timeout))) &&
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atomic_read(&bat_priv->mesh_state) == BATADV_MESH_ACTIVE)
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continue;
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if (curr_gw == gw_node)
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do_deselect = 1;
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hlist_del_rcu(&gw_node->list);
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batadv_gw_node_free_ref(gw_node);
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}
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spin_unlock_bh(&bat_priv->gw.list_lock);
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/* gw_deselect() needs to acquire the gw_list_lock */
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if (do_deselect)
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batadv_gw_deselect(bat_priv);
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if (curr_gw)
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batadv_gw_node_free_ref(curr_gw);
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}
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/* fails if orig_node has no router */
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static int batadv_write_buffer_text(struct batadv_priv *bat_priv,
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struct seq_file *seq,
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const struct batadv_gw_node *gw_node)
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{
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struct batadv_gw_node *curr_gw;
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struct batadv_neigh_node *router;
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int down, up, ret = -1;
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batadv_gw_bandwidth_to_kbit(gw_node->orig_node->gw_flags, &down, &up);
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router = batadv_orig_node_get_router(gw_node->orig_node);
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if (!router)
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goto out;
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curr_gw = batadv_gw_get_selected_gw_node(bat_priv);
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ret = seq_printf(seq, "%s %pM (%3i) %pM [%10s]: %3i - %i%s/%i%s\n",
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(curr_gw == gw_node ? "=>" : " "),
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gw_node->orig_node->orig,
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router->tq_avg, router->addr,
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router->if_incoming->net_dev->name,
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gw_node->orig_node->gw_flags,
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(down > 2048 ? down / 1024 : down),
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(down > 2048 ? "MBit" : "KBit"),
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(up > 2048 ? up / 1024 : up),
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(up > 2048 ? "MBit" : "KBit"));
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batadv_neigh_node_free_ref(router);
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if (curr_gw)
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batadv_gw_node_free_ref(curr_gw);
|
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out:
|
|
return ret;
|
|
}
|
|
|
|
int batadv_gw_client_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_hard_iface *primary_if;
|
|
struct batadv_gw_node *gw_node;
|
|
struct hlist_node *node;
|
|
int gw_count = 0, ret = 0;
|
|
|
|
primary_if = batadv_primary_if_get_selected(bat_priv);
|
|
if (!primary_if) {
|
|
ret = seq_printf(seq,
|
|
"BATMAN mesh %s disabled - please specify interfaces to enable it\n",
|
|
net_dev->name);
|
|
goto out;
|
|
}
|
|
|
|
if (primary_if->if_status != BATADV_IF_ACTIVE) {
|
|
ret = seq_printf(seq,
|
|
"BATMAN mesh %s disabled - primary interface not active\n",
|
|
net_dev->name);
|
|
goto out;
|
|
}
|
|
|
|
seq_printf(seq,
|
|
" %-12s (%s/%i) %17s [%10s]: gw_class ... [B.A.T.M.A.N. adv %s, MainIF/MAC: %s/%pM (%s)]\n",
|
|
"Gateway", "#", BATADV_TQ_MAX_VALUE, "Nexthop", "outgoingIF",
|
|
BATADV_SOURCE_VERSION, primary_if->net_dev->name,
|
|
primary_if->net_dev->dev_addr, net_dev->name);
|
|
|
|
rcu_read_lock();
|
|
hlist_for_each_entry_rcu(gw_node, node, &bat_priv->gw.list, list) {
|
|
if (gw_node->deleted)
|
|
continue;
|
|
|
|
/* fails if orig_node has no router */
|
|
if (batadv_write_buffer_text(bat_priv, seq, gw_node) < 0)
|
|
continue;
|
|
|
|
gw_count++;
|
|
}
|
|
rcu_read_unlock();
|
|
|
|
if (gw_count == 0)
|
|
seq_printf(seq, "No gateways in range ...\n");
|
|
|
|
out:
|
|
if (primary_if)
|
|
batadv_hardif_free_ref(primary_if);
|
|
return ret;
|
|
}
|
|
|
|
static bool batadv_is_type_dhcprequest(struct sk_buff *skb, int header_len)
|
|
{
|
|
int ret = false;
|
|
unsigned char *p;
|
|
int pkt_len;
|
|
|
|
if (skb_linearize(skb) < 0)
|
|
goto out;
|
|
|
|
pkt_len = skb_headlen(skb);
|
|
|
|
if (pkt_len < header_len + BATADV_DHCP_OPTIONS_OFFSET + 1)
|
|
goto out;
|
|
|
|
p = skb->data + header_len + BATADV_DHCP_OPTIONS_OFFSET;
|
|
pkt_len -= header_len + BATADV_DHCP_OPTIONS_OFFSET + 1;
|
|
|
|
/* Access the dhcp option lists. Each entry is made up by:
|
|
* - octet 1: option type
|
|
* - octet 2: option data len (only if type != 255 and 0)
|
|
* - octet 3: option data
|
|
*/
|
|
while (*p != 255 && !ret) {
|
|
/* p now points to the first octet: option type */
|
|
if (*p == 53) {
|
|
/* type 53 is the message type option.
|
|
* Jump the len octet and go to the data octet
|
|
*/
|
|
if (pkt_len < 2)
|
|
goto out;
|
|
p += 2;
|
|
|
|
/* check if the message type is what we need */
|
|
if (*p == BATADV_DHCP_REQUEST)
|
|
ret = true;
|
|
break;
|
|
} else if (*p == 0) {
|
|
/* option type 0 (padding), just go forward */
|
|
if (pkt_len < 1)
|
|
goto out;
|
|
pkt_len--;
|
|
p++;
|
|
} else {
|
|
/* This is any other option. So we get the length... */
|
|
if (pkt_len < 1)
|
|
goto out;
|
|
pkt_len--;
|
|
p++;
|
|
|
|
/* ...and then we jump over the data */
|
|
if (pkt_len < 1 + (*p))
|
|
goto out;
|
|
pkt_len -= 1 + (*p);
|
|
p += 1 + (*p);
|
|
}
|
|
}
|
|
out:
|
|
return ret;
|
|
}
|
|
|
|
bool batadv_gw_is_dhcp_target(struct sk_buff *skb, unsigned int *header_len)
|
|
{
|
|
struct ethhdr *ethhdr;
|
|
struct iphdr *iphdr;
|
|
struct ipv6hdr *ipv6hdr;
|
|
struct udphdr *udphdr;
|
|
|
|
/* check for ethernet header */
|
|
if (!pskb_may_pull(skb, *header_len + ETH_HLEN))
|
|
return false;
|
|
ethhdr = (struct ethhdr *)skb->data;
|
|
*header_len += ETH_HLEN;
|
|
|
|
/* check for initial vlan header */
|
|
if (ntohs(ethhdr->h_proto) == ETH_P_8021Q) {
|
|
if (!pskb_may_pull(skb, *header_len + VLAN_HLEN))
|
|
return false;
|
|
ethhdr = (struct ethhdr *)(skb->data + VLAN_HLEN);
|
|
*header_len += VLAN_HLEN;
|
|
}
|
|
|
|
/* check for ip header */
|
|
switch (ntohs(ethhdr->h_proto)) {
|
|
case ETH_P_IP:
|
|
if (!pskb_may_pull(skb, *header_len + sizeof(*iphdr)))
|
|
return false;
|
|
iphdr = (struct iphdr *)(skb->data + *header_len);
|
|
*header_len += iphdr->ihl * 4;
|
|
|
|
/* check for udp header */
|
|
if (iphdr->protocol != IPPROTO_UDP)
|
|
return false;
|
|
|
|
break;
|
|
case ETH_P_IPV6:
|
|
if (!pskb_may_pull(skb, *header_len + sizeof(*ipv6hdr)))
|
|
return false;
|
|
ipv6hdr = (struct ipv6hdr *)(skb->data + *header_len);
|
|
*header_len += sizeof(*ipv6hdr);
|
|
|
|
/* check for udp header */
|
|
if (ipv6hdr->nexthdr != IPPROTO_UDP)
|
|
return false;
|
|
|
|
break;
|
|
default:
|
|
return false;
|
|
}
|
|
|
|
if (!pskb_may_pull(skb, *header_len + sizeof(*udphdr)))
|
|
return false;
|
|
udphdr = (struct udphdr *)(skb->data + *header_len);
|
|
*header_len += sizeof(*udphdr);
|
|
|
|
/* check for bootp port */
|
|
if ((ntohs(ethhdr->h_proto) == ETH_P_IP) &&
|
|
(ntohs(udphdr->dest) != 67))
|
|
return false;
|
|
|
|
if ((ntohs(ethhdr->h_proto) == ETH_P_IPV6) &&
|
|
(ntohs(udphdr->dest) != 547))
|
|
return false;
|
|
|
|
return true;
|
|
}
|
|
|
|
bool batadv_gw_out_of_range(struct batadv_priv *bat_priv,
|
|
struct sk_buff *skb, struct ethhdr *ethhdr)
|
|
{
|
|
struct batadv_neigh_node *neigh_curr = NULL, *neigh_old = NULL;
|
|
struct batadv_orig_node *orig_dst_node = NULL;
|
|
struct batadv_gw_node *curr_gw = NULL;
|
|
bool ret, out_of_range = false;
|
|
unsigned int header_len = 0;
|
|
uint8_t curr_tq_avg;
|
|
|
|
ret = batadv_gw_is_dhcp_target(skb, &header_len);
|
|
if (!ret)
|
|
goto out;
|
|
|
|
orig_dst_node = batadv_transtable_search(bat_priv, ethhdr->h_source,
|
|
ethhdr->h_dest);
|
|
if (!orig_dst_node)
|
|
goto out;
|
|
|
|
if (!orig_dst_node->gw_flags)
|
|
goto out;
|
|
|
|
ret = batadv_is_type_dhcprequest(skb, header_len);
|
|
if (!ret)
|
|
goto out;
|
|
|
|
switch (atomic_read(&bat_priv->gw_mode)) {
|
|
case BATADV_GW_MODE_SERVER:
|
|
/* If we are a GW then we are our best GW. We can artificially
|
|
* set the tq towards ourself as the maximum value
|
|
*/
|
|
curr_tq_avg = BATADV_TQ_MAX_VALUE;
|
|
break;
|
|
case BATADV_GW_MODE_CLIENT:
|
|
curr_gw = batadv_gw_get_selected_gw_node(bat_priv);
|
|
if (!curr_gw)
|
|
goto out;
|
|
|
|
/* packet is going to our gateway */
|
|
if (curr_gw->orig_node == orig_dst_node)
|
|
goto out;
|
|
|
|
/* If the dhcp packet has been sent to a different gw,
|
|
* we have to evaluate whether the old gw is still
|
|
* reliable enough
|
|
*/
|
|
neigh_curr = batadv_find_router(bat_priv, curr_gw->orig_node,
|
|
NULL);
|
|
if (!neigh_curr)
|
|
goto out;
|
|
|
|
curr_tq_avg = neigh_curr->tq_avg;
|
|
break;
|
|
case BATADV_GW_MODE_OFF:
|
|
default:
|
|
goto out;
|
|
}
|
|
|
|
neigh_old = batadv_find_router(bat_priv, orig_dst_node, NULL);
|
|
if (!neigh_old)
|
|
goto out;
|
|
|
|
if (curr_tq_avg - neigh_old->tq_avg > BATADV_GW_THRESHOLD)
|
|
out_of_range = true;
|
|
|
|
out:
|
|
if (orig_dst_node)
|
|
batadv_orig_node_free_ref(orig_dst_node);
|
|
if (curr_gw)
|
|
batadv_gw_node_free_ref(curr_gw);
|
|
if (neigh_old)
|
|
batadv_neigh_node_free_ref(neigh_old);
|
|
if (neigh_curr)
|
|
batadv_neigh_node_free_ref(neigh_curr);
|
|
return out_of_range;
|
|
}
|