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linux/net/batman-adv/bat_iv_ogm.c

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/* Copyright (C) 2007-2012 B.A.T.M.A.N. contributors:
*
* Marek Lindner, Simon Wunderlich
*
* This program is free software; you can redistribute it and/or
* modify it under the terms of version 2 of the GNU General Public
* License as published by the Free Software Foundation.
*
* This program is distributed in the hope that it will be useful, but
* WITHOUT ANY WARRANTY; without even the implied warranty of
* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
* General Public License for more details.
*
* You should have received a copy of the GNU General Public License
* along with this program; if not, write to the Free Software
* Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA
* 02110-1301, USA
*/
#include "main.h"
#include "translation-table.h"
#include "ring_buffer.h"
#include "originator.h"
#include "routing.h"
#include "gateway_common.h"
#include "gateway_client.h"
#include "hard-interface.h"
#include "send.h"
#include "bat_algo.h"
static struct neigh_node *batadv_iv_ogm_neigh_new(struct hard_iface *hard_iface,
const uint8_t *neigh_addr,
struct orig_node *orig_node,
struct orig_node *orig_neigh,
__be32 seqno)
{
struct neigh_node *neigh_node;
neigh_node = batadv_neigh_node_new(hard_iface, neigh_addr,
ntohl(seqno));
if (!neigh_node)
goto out;
INIT_LIST_HEAD(&neigh_node->bonding_list);
neigh_node->orig_node = orig_neigh;
neigh_node->if_incoming = hard_iface;
spin_lock_bh(&orig_node->neigh_list_lock);
hlist_add_head_rcu(&neigh_node->list, &orig_node->neigh_list);
spin_unlock_bh(&orig_node->neigh_list_lock);
out:
return neigh_node;
}
static int batadv_iv_ogm_iface_enable(struct hard_iface *hard_iface)
{
struct batman_ogm_packet *batman_ogm_packet;
uint32_t random_seqno;
int res = -ENOMEM;
/* randomize initial seqno to avoid collision */
get_random_bytes(&random_seqno, sizeof(random_seqno));
atomic_set(&hard_iface->seqno, random_seqno);
hard_iface->packet_len = BATMAN_OGM_HLEN;
hard_iface->packet_buff = kmalloc(hard_iface->packet_len, GFP_ATOMIC);
if (!hard_iface->packet_buff)
goto out;
batman_ogm_packet = (struct batman_ogm_packet *)hard_iface->packet_buff;
batman_ogm_packet->header.packet_type = BAT_IV_OGM;
batman_ogm_packet->header.version = COMPAT_VERSION;
batman_ogm_packet->header.ttl = 2;
batman_ogm_packet->flags = NO_FLAGS;
batman_ogm_packet->tq = TQ_MAX_VALUE;
batman_ogm_packet->tt_num_changes = 0;
batman_ogm_packet->ttvn = 0;
res = 0;
out:
return res;
}
static void batadv_iv_ogm_iface_disable(struct hard_iface *hard_iface)
{
kfree(hard_iface->packet_buff);
hard_iface->packet_buff = NULL;
}
static void batadv_iv_ogm_iface_update_mac(struct hard_iface *hard_iface)
{
struct batman_ogm_packet *batman_ogm_packet;
batman_ogm_packet = (struct batman_ogm_packet *)hard_iface->packet_buff;
memcpy(batman_ogm_packet->orig,
hard_iface->net_dev->dev_addr, ETH_ALEN);
memcpy(batman_ogm_packet->prev_sender,
hard_iface->net_dev->dev_addr, ETH_ALEN);
}
static void batadv_iv_ogm_primary_iface_set(struct hard_iface *hard_iface)
{
struct batman_ogm_packet *batman_ogm_packet;
batman_ogm_packet = (struct batman_ogm_packet *)hard_iface->packet_buff;
batman_ogm_packet->flags = PRIMARIES_FIRST_HOP;
batman_ogm_packet->header.ttl = TTL;
}
/* when do we schedule our own ogm to be sent */
static unsigned long
batadv_iv_ogm_emit_send_time(const struct bat_priv *bat_priv)
{
return jiffies + msecs_to_jiffies(
atomic_read(&bat_priv->orig_interval) -
JITTER + (random32() % 2*JITTER));
}
/* when do we schedule a ogm packet to be sent */
static unsigned long batadv_iv_ogm_fwd_send_time(void)
{
return jiffies + msecs_to_jiffies(random32() % (JITTER/2));
}
/* apply hop penalty for a normal link */
static uint8_t batadv_hop_penalty(uint8_t tq, const struct bat_priv *bat_priv)
{
int hop_penalty = atomic_read(&bat_priv->hop_penalty);
return (tq * (TQ_MAX_VALUE - hop_penalty)) / (TQ_MAX_VALUE);
}
/* is there another aggregated packet here? */
static int batadv_iv_ogm_aggr_packet(int buff_pos, int packet_len,
int tt_num_changes)
{
int next_buff_pos = 0;
next_buff_pos += buff_pos + BATMAN_OGM_HLEN;
next_buff_pos += batadv_tt_len(tt_num_changes);
return (next_buff_pos <= packet_len) &&
(next_buff_pos <= MAX_AGGREGATION_BYTES);
}
/* send a batman ogm to a given interface */
static void batadv_iv_ogm_send_to_if(struct forw_packet *forw_packet,
struct hard_iface *hard_iface)
{
struct bat_priv *bat_priv = netdev_priv(hard_iface->soft_iface);
char *fwd_str;
uint8_t packet_num;
int16_t buff_pos;
struct batman_ogm_packet *batman_ogm_packet;
struct sk_buff *skb;
if (hard_iface->if_status != IF_ACTIVE)
return;
packet_num = 0;
buff_pos = 0;
batman_ogm_packet = (struct batman_ogm_packet *)forw_packet->skb->data;
/* adjust all flags and log packets */
while (batadv_iv_ogm_aggr_packet(buff_pos, forw_packet->packet_len,
batman_ogm_packet->tt_num_changes)) {
/* we might have aggregated direct link packets with an
* ordinary base packet
*/
if ((forw_packet->direct_link_flags & (1 << packet_num)) &&
(forw_packet->if_incoming == hard_iface))
batman_ogm_packet->flags |= DIRECTLINK;
else
batman_ogm_packet->flags &= ~DIRECTLINK;
fwd_str = (packet_num > 0 ? "Forwarding" : (forw_packet->own ?
"Sending own" :
"Forwarding"));
batadv_dbg(DBG_BATMAN, bat_priv,
"%s %spacket (originator %pM, seqno %u, TQ %d, TTL %d, IDF %s, ttvn %d) on interface %s [%pM]\n",
fwd_str, (packet_num > 0 ? "aggregated " : ""),
batman_ogm_packet->orig,
ntohl(batman_ogm_packet->seqno),
batman_ogm_packet->tq, batman_ogm_packet->header.ttl,
(batman_ogm_packet->flags & DIRECTLINK ?
"on" : "off"),
batman_ogm_packet->ttvn, hard_iface->net_dev->name,
hard_iface->net_dev->dev_addr);
buff_pos += BATMAN_OGM_HLEN;
buff_pos += batadv_tt_len(batman_ogm_packet->tt_num_changes);
packet_num++;
batman_ogm_packet = (struct batman_ogm_packet *)
(forw_packet->skb->data + buff_pos);
}
/* create clone because function is called more than once */
skb = skb_clone(forw_packet->skb, GFP_ATOMIC);
if (skb) {
batadv_inc_counter(bat_priv, BAT_CNT_MGMT_TX);
batadv_add_counter(bat_priv, BAT_CNT_MGMT_TX_BYTES,
skb->len + ETH_HLEN);
batadv_send_skb_packet(skb, hard_iface, batadv_broadcast_addr);
}
}
/* send a batman ogm packet */
static void batadv_iv_ogm_emit(struct forw_packet *forw_packet)
{
struct hard_iface *hard_iface;
struct net_device *soft_iface;
struct bat_priv *bat_priv;
struct hard_iface *primary_if = NULL;
struct batman_ogm_packet *batman_ogm_packet;
unsigned char directlink;
batman_ogm_packet = (struct batman_ogm_packet *)
(forw_packet->skb->data);
directlink = (batman_ogm_packet->flags & DIRECTLINK ? 1 : 0);
if (!forw_packet->if_incoming) {
pr_err("Error - can't forward packet: incoming iface not specified\n");
goto out;
}
soft_iface = forw_packet->if_incoming->soft_iface;
bat_priv = netdev_priv(soft_iface);
if (forw_packet->if_incoming->if_status != IF_ACTIVE)
goto out;
primary_if = batadv_primary_if_get_selected(bat_priv);
if (!primary_if)
goto out;
/* multihomed peer assumed
* non-primary OGMs are only broadcasted on their interface
*/
if ((directlink && (batman_ogm_packet->header.ttl == 1)) ||
(forw_packet->own && (forw_packet->if_incoming != primary_if))) {
/* FIXME: what about aggregated packets ? */
batadv_dbg(DBG_BATMAN, bat_priv,
"%s packet (originator %pM, seqno %u, TTL %d) on interface %s [%pM]\n",
(forw_packet->own ? "Sending own" : "Forwarding"),
batman_ogm_packet->orig,
ntohl(batman_ogm_packet->seqno),
batman_ogm_packet->header.ttl,
forw_packet->if_incoming->net_dev->name,
forw_packet->if_incoming->net_dev->dev_addr);
/* skb is only used once and than forw_packet is free'd */
batadv_send_skb_packet(forw_packet->skb,
forw_packet->if_incoming,
batadv_broadcast_addr);
forw_packet->skb = NULL;
goto out;
}
/* broadcast on every interface */
rcu_read_lock();
list_for_each_entry_rcu(hard_iface, &batadv_hardif_list, list) {
if (hard_iface->soft_iface != soft_iface)
continue;
batadv_iv_ogm_send_to_if(forw_packet, hard_iface);
}
rcu_read_unlock();
out:
if (primary_if)
batadv_hardif_free_ref(primary_if);
}
/* return true if new_packet can be aggregated with forw_packet */
static bool
batadv_iv_ogm_can_aggregate(const struct batman_ogm_packet *new_bat_ogm_packet,
struct bat_priv *bat_priv,
int packet_len, unsigned long send_time,
bool directlink,
const struct hard_iface *if_incoming,
const struct forw_packet *forw_packet)
{
struct batman_ogm_packet *batman_ogm_packet;
int aggregated_bytes = forw_packet->packet_len + packet_len;
struct hard_iface *primary_if = NULL;
bool res = false;
batman_ogm_packet = (struct batman_ogm_packet *)forw_packet->skb->data;
/* we can aggregate the current packet to this aggregated packet
* if:
*
* - the send time is within our MAX_AGGREGATION_MS time
* - the resulting packet wont be bigger than
* MAX_AGGREGATION_BYTES
*/
if (time_before(send_time, forw_packet->send_time) &&
time_after_eq(send_time + msecs_to_jiffies(MAX_AGGREGATION_MS),
forw_packet->send_time) &&
(aggregated_bytes <= MAX_AGGREGATION_BYTES)) {
/* check aggregation compatibility
* -> direct link packets are broadcasted on
* their interface only
* -> aggregate packet if the current packet is
* a "global" packet as well as the base
* packet
*/
primary_if = batadv_primary_if_get_selected(bat_priv);
if (!primary_if)
goto out;
/* packets without direct link flag and high TTL
* are flooded through the net
*/
if ((!directlink) &&
(!(batman_ogm_packet->flags & DIRECTLINK)) &&
(batman_ogm_packet->header.ttl != 1) &&
/* own packets originating non-primary
* interfaces leave only that interface
*/
((!forw_packet->own) ||
(forw_packet->if_incoming == primary_if))) {
res = true;
goto out;
}
/* if the incoming packet is sent via this one
* interface only - we still can aggregate
*/
if ((directlink) &&
(new_bat_ogm_packet->header.ttl == 1) &&
(forw_packet->if_incoming == if_incoming) &&
/* packets from direct neighbors or
* own secondary interface packets
* (= secondary interface packets in general)
*/
(batman_ogm_packet->flags & DIRECTLINK ||
(forw_packet->own &&
forw_packet->if_incoming != primary_if))) {
res = true;
goto out;
}
}
out:
if (primary_if)
batadv_hardif_free_ref(primary_if);
return res;
}
/* create a new aggregated packet and add this packet to it */
static void batadv_iv_ogm_aggregate_new(const unsigned char *packet_buff,
int packet_len, unsigned long send_time,
bool direct_link,
struct hard_iface *if_incoming,
int own_packet)
{
struct bat_priv *bat_priv = netdev_priv(if_incoming->soft_iface);
struct forw_packet *forw_packet_aggr;
unsigned char *skb_buff;
if (!atomic_inc_not_zero(&if_incoming->refcount))
return;
/* own packet should always be scheduled */
if (!own_packet) {
if (!atomic_dec_not_zero(&bat_priv->batman_queue_left)) {
batadv_dbg(DBG_BATMAN, bat_priv,
"batman packet queue full\n");
goto out;
}
}
forw_packet_aggr = kmalloc(sizeof(*forw_packet_aggr), GFP_ATOMIC);
if (!forw_packet_aggr) {
if (!own_packet)
atomic_inc(&bat_priv->batman_queue_left);
goto out;
}
if ((atomic_read(&bat_priv->aggregated_ogms)) &&
(packet_len < MAX_AGGREGATION_BYTES))
forw_packet_aggr->skb = dev_alloc_skb(MAX_AGGREGATION_BYTES +
ETH_HLEN);
else
forw_packet_aggr->skb = dev_alloc_skb(packet_len + ETH_HLEN);
if (!forw_packet_aggr->skb) {
if (!own_packet)
atomic_inc(&bat_priv->batman_queue_left);
kfree(forw_packet_aggr);
goto out;
}
skb_reserve(forw_packet_aggr->skb, ETH_HLEN);
INIT_HLIST_NODE(&forw_packet_aggr->list);
skb_buff = skb_put(forw_packet_aggr->skb, packet_len);
forw_packet_aggr->packet_len = packet_len;
memcpy(skb_buff, packet_buff, packet_len);
forw_packet_aggr->own = own_packet;
forw_packet_aggr->if_incoming = if_incoming;
forw_packet_aggr->num_packets = 0;
forw_packet_aggr->direct_link_flags = NO_FLAGS;
forw_packet_aggr->send_time = send_time;
/* save packet direct link flag status */
if (direct_link)
forw_packet_aggr->direct_link_flags |= 1;
/* add new packet to packet list */
spin_lock_bh(&bat_priv->forw_bat_list_lock);
hlist_add_head(&forw_packet_aggr->list, &bat_priv->forw_bat_list);
spin_unlock_bh(&bat_priv->forw_bat_list_lock);
/* start timer for this packet */
INIT_DELAYED_WORK(&forw_packet_aggr->delayed_work,
batadv_send_outstanding_bat_ogm_packet);
queue_delayed_work(batadv_event_workqueue,
&forw_packet_aggr->delayed_work,
send_time - jiffies);
return;
out:
batadv_hardif_free_ref(if_incoming);
}
/* aggregate a new packet into the existing ogm packet */
static void batadv_iv_ogm_aggregate(struct forw_packet *forw_packet_aggr,
const unsigned char *packet_buff,
int packet_len, bool direct_link)
{
unsigned char *skb_buff;
skb_buff = skb_put(forw_packet_aggr->skb, packet_len);
memcpy(skb_buff, packet_buff, packet_len);
forw_packet_aggr->packet_len += packet_len;
forw_packet_aggr->num_packets++;
/* save packet direct link flag status */
if (direct_link)
forw_packet_aggr->direct_link_flags |=
(1 << forw_packet_aggr->num_packets);
}
static void batadv_iv_ogm_queue_add(struct bat_priv *bat_priv,
unsigned char *packet_buff,
int packet_len,
struct hard_iface *if_incoming,
int own_packet, unsigned long send_time)
{
/* _aggr -> pointer to the packet we want to aggregate with
* _pos -> pointer to the position in the queue
*/
struct forw_packet *forw_packet_aggr = NULL, *forw_packet_pos = NULL;
struct hlist_node *tmp_node;
struct batman_ogm_packet *batman_ogm_packet;
bool direct_link;
batman_ogm_packet = (struct batman_ogm_packet *)packet_buff;
direct_link = batman_ogm_packet->flags & DIRECTLINK ? 1 : 0;
/* find position for the packet in the forward queue */
spin_lock_bh(&bat_priv->forw_bat_list_lock);
/* own packets are not to be aggregated */
if ((atomic_read(&bat_priv->aggregated_ogms)) && (!own_packet)) {
hlist_for_each_entry(forw_packet_pos, tmp_node,
&bat_priv->forw_bat_list, list) {
if (batadv_iv_ogm_can_aggregate(batman_ogm_packet,
bat_priv, packet_len,
send_time, direct_link,
if_incoming,
forw_packet_pos)) {
forw_packet_aggr = forw_packet_pos;
break;
}
}
}
/* nothing to aggregate with - either aggregation disabled or no
* suitable aggregation packet found
*/
if (!forw_packet_aggr) {
/* the following section can run without the lock */
spin_unlock_bh(&bat_priv->forw_bat_list_lock);
/* if we could not aggregate this packet with one of the others
* we hold it back for a while, so that it might be aggregated
* later on
*/
if ((!own_packet) &&
(atomic_read(&bat_priv->aggregated_ogms)))
send_time += msecs_to_jiffies(MAX_AGGREGATION_MS);
batadv_iv_ogm_aggregate_new(packet_buff, packet_len,
send_time, direct_link,
if_incoming, own_packet);
} else {
batadv_iv_ogm_aggregate(forw_packet_aggr, packet_buff,
packet_len, direct_link);
spin_unlock_bh(&bat_priv->forw_bat_list_lock);
}
}
static void batadv_iv_ogm_forward(struct orig_node *orig_node,
const struct ethhdr *ethhdr,
struct batman_ogm_packet *batman_ogm_packet,
bool is_single_hop_neigh,
bool is_from_best_next_hop,
struct hard_iface *if_incoming)
{
struct bat_priv *bat_priv = netdev_priv(if_incoming->soft_iface);
uint8_t tt_num_changes;
if (batman_ogm_packet->header.ttl <= 1) {
batadv_dbg(DBG_BATMAN, bat_priv, "ttl exceeded\n");
return;
}
if (!is_from_best_next_hop) {
/* Mark the forwarded packet when it is not coming from our
* best next hop. We still need to forward the packet for our
* neighbor link quality detection to work in case the packet
* originated from a single hop neighbor. Otherwise we can
* simply drop the ogm.
*/
if (is_single_hop_neigh)
batman_ogm_packet->flags |= NOT_BEST_NEXT_HOP;
else
return;
}
tt_num_changes = batman_ogm_packet->tt_num_changes;
batman_ogm_packet->header.ttl--;
memcpy(batman_ogm_packet->prev_sender, ethhdr->h_source, ETH_ALEN);
/* apply hop penalty */
batman_ogm_packet->tq = batadv_hop_penalty(batman_ogm_packet->tq,
bat_priv);
batadv_dbg(DBG_BATMAN, bat_priv,
"Forwarding packet: tq: %i, ttl: %i\n",
batman_ogm_packet->tq, batman_ogm_packet->header.ttl);
/* switch of primaries first hop flag when forwarding */
batman_ogm_packet->flags &= ~PRIMARIES_FIRST_HOP;
if (is_single_hop_neigh)
batman_ogm_packet->flags |= DIRECTLINK;
else
batman_ogm_packet->flags &= ~DIRECTLINK;
batadv_iv_ogm_queue_add(bat_priv, (unsigned char *)batman_ogm_packet,
BATMAN_OGM_HLEN + batadv_tt_len(tt_num_changes),
if_incoming, 0, batadv_iv_ogm_fwd_send_time());
}
static void batadv_iv_ogm_schedule(struct hard_iface *hard_iface)
{
struct bat_priv *bat_priv = netdev_priv(hard_iface->soft_iface);
struct batman_ogm_packet *batman_ogm_packet;
struct hard_iface *primary_if;
int vis_server, tt_num_changes = 0;
vis_server = atomic_read(&bat_priv->vis_mode);
primary_if = batadv_primary_if_get_selected(bat_priv);
if (hard_iface == primary_if)
tt_num_changes = batadv_tt_append_diff(bat_priv,
&hard_iface->packet_buff,
&hard_iface->packet_len,
BATMAN_OGM_HLEN);
batman_ogm_packet = (struct batman_ogm_packet *)hard_iface->packet_buff;
/* change sequence number to network order */
batman_ogm_packet->seqno =
htonl((uint32_t)atomic_read(&hard_iface->seqno));
atomic_inc(&hard_iface->seqno);
batman_ogm_packet->ttvn = atomic_read(&bat_priv->ttvn);
batman_ogm_packet->tt_crc = htons(bat_priv->tt_crc);
if (tt_num_changes >= 0)
batman_ogm_packet->tt_num_changes = tt_num_changes;
if (vis_server == VIS_TYPE_SERVER_SYNC)
batman_ogm_packet->flags |= VIS_SERVER;
else
batman_ogm_packet->flags &= ~VIS_SERVER;
if ((hard_iface == primary_if) &&
(atomic_read(&bat_priv->gw_mode) == GW_MODE_SERVER))
batman_ogm_packet->gw_flags =
(uint8_t)atomic_read(&bat_priv->gw_bandwidth);
else
batman_ogm_packet->gw_flags = NO_FLAGS;
batadv_slide_own_bcast_window(hard_iface);
batadv_iv_ogm_queue_add(bat_priv, hard_iface->packet_buff,
hard_iface->packet_len, hard_iface, 1,
batadv_iv_ogm_emit_send_time(bat_priv));
if (primary_if)
batadv_hardif_free_ref(primary_if);
}
static void
batadv_iv_ogm_orig_update(struct bat_priv *bat_priv,
struct orig_node *orig_node,
const struct ethhdr *ethhdr,
const struct batman_ogm_packet *batman_ogm_packet,
struct hard_iface *if_incoming,
const unsigned char *tt_buff,
int is_duplicate)
{
struct neigh_node *neigh_node = NULL, *tmp_neigh_node = NULL;
struct neigh_node *router = NULL;
struct orig_node *orig_node_tmp;
struct hlist_node *node;
uint8_t bcast_own_sum_orig, bcast_own_sum_neigh;
uint8_t *neigh_addr;
batadv_dbg(DBG_BATMAN, bat_priv,
"update_originator(): Searching and updating originator entry of received packet\n");
rcu_read_lock();
hlist_for_each_entry_rcu(tmp_neigh_node, node,
&orig_node->neigh_list, list) {
neigh_addr = tmp_neigh_node->addr;
if (batadv_compare_eth(neigh_addr, ethhdr->h_source) &&
tmp_neigh_node->if_incoming == if_incoming &&
atomic_inc_not_zero(&tmp_neigh_node->refcount)) {
if (neigh_node)
batadv_neigh_node_free_ref(neigh_node);
neigh_node = tmp_neigh_node;
continue;
}
if (is_duplicate)
continue;
spin_lock_bh(&tmp_neigh_node->lq_update_lock);
batadv_ring_buffer_set(tmp_neigh_node->tq_recv,
&tmp_neigh_node->tq_index, 0);
tmp_neigh_node->tq_avg =
batadv_ring_buffer_avg(tmp_neigh_node->tq_recv);
spin_unlock_bh(&tmp_neigh_node->lq_update_lock);
}
if (!neigh_node) {
struct orig_node *orig_tmp;
orig_tmp = batadv_get_orig_node(bat_priv, ethhdr->h_source);
if (!orig_tmp)
goto unlock;
neigh_node = batadv_iv_ogm_neigh_new(if_incoming,
ethhdr->h_source,
orig_node, orig_tmp,
batman_ogm_packet->seqno);
batadv_orig_node_free_ref(orig_tmp);
if (!neigh_node)
goto unlock;
} else
batadv_dbg(DBG_BATMAN, bat_priv,
"Updating existing last-hop neighbor of originator\n");
rcu_read_unlock();
orig_node->flags = batman_ogm_packet->flags;
neigh_node->last_seen = jiffies;
spin_lock_bh(&neigh_node->lq_update_lock);
batadv_ring_buffer_set(neigh_node->tq_recv,
&neigh_node->tq_index,
batman_ogm_packet->tq);
neigh_node->tq_avg = batadv_ring_buffer_avg(neigh_node->tq_recv);
spin_unlock_bh(&neigh_node->lq_update_lock);
if (!is_duplicate) {
orig_node->last_ttl = batman_ogm_packet->header.ttl;
neigh_node->last_ttl = batman_ogm_packet->header.ttl;
}
batadv_bonding_candidate_add(orig_node, neigh_node);
/* if this neighbor already is our next hop there is nothing
* to change
*/
router = batadv_orig_node_get_router(orig_node);
if (router == neigh_node)
goto update_tt;
/* if this neighbor does not offer a better TQ we won't consider it */
if (router && (router->tq_avg > neigh_node->tq_avg))
goto update_tt;
/* if the TQ is the same and the link not more symmetric we
* won't consider it either
*/
if (router && (neigh_node->tq_avg == router->tq_avg)) {
orig_node_tmp = router->orig_node;
spin_lock_bh(&orig_node_tmp->ogm_cnt_lock);
bcast_own_sum_orig =
orig_node_tmp->bcast_own_sum[if_incoming->if_num];
spin_unlock_bh(&orig_node_tmp->ogm_cnt_lock);
orig_node_tmp = neigh_node->orig_node;
spin_lock_bh(&orig_node_tmp->ogm_cnt_lock);
bcast_own_sum_neigh =
orig_node_tmp->bcast_own_sum[if_incoming->if_num];
spin_unlock_bh(&orig_node_tmp->ogm_cnt_lock);
if (bcast_own_sum_orig >= bcast_own_sum_neigh)
goto update_tt;
}
batadv_update_route(bat_priv, orig_node, neigh_node);
update_tt:
/* I have to check for transtable changes only if the OGM has been
* sent through a primary interface
*/
if (((batman_ogm_packet->orig != ethhdr->h_source) &&
(batman_ogm_packet->header.ttl > 2)) ||
(batman_ogm_packet->flags & PRIMARIES_FIRST_HOP))
batadv_tt_update_orig(bat_priv, orig_node, tt_buff,
batman_ogm_packet->tt_num_changes,
batman_ogm_packet->ttvn,
ntohs(batman_ogm_packet->tt_crc));
if (orig_node->gw_flags != batman_ogm_packet->gw_flags)
batadv_gw_node_update(bat_priv, orig_node,
batman_ogm_packet->gw_flags);
orig_node->gw_flags = batman_ogm_packet->gw_flags;
/* restart gateway selection if fast or late switching was enabled */
if ((orig_node->gw_flags) &&
(atomic_read(&bat_priv->gw_mode) == GW_MODE_CLIENT) &&
(atomic_read(&bat_priv->gw_sel_class) > 2))
batadv_gw_check_election(bat_priv, orig_node);
goto out;
unlock:
rcu_read_unlock();
out:
if (neigh_node)
batadv_neigh_node_free_ref(neigh_node);
if (router)
batadv_neigh_node_free_ref(router);
}
static int batadv_iv_ogm_calc_tq(struct orig_node *orig_node,
struct orig_node *orig_neigh_node,
struct batman_ogm_packet *batman_ogm_packet,
struct hard_iface *if_incoming)
{
struct bat_priv *bat_priv = netdev_priv(if_incoming->soft_iface);
struct neigh_node *neigh_node = NULL, *tmp_neigh_node;
struct hlist_node *node;
uint8_t total_count;
uint8_t orig_eq_count, neigh_rq_count, tq_own;
int tq_asym_penalty, ret = 0;
/* find corresponding one hop neighbor */
rcu_read_lock();
hlist_for_each_entry_rcu(tmp_neigh_node, node,
&orig_neigh_node->neigh_list, list) {
if (!batadv_compare_eth(tmp_neigh_node->addr,
orig_neigh_node->orig))
continue;
if (tmp_neigh_node->if_incoming != if_incoming)
continue;
if (!atomic_inc_not_zero(&tmp_neigh_node->refcount))
continue;
neigh_node = tmp_neigh_node;
break;
}
rcu_read_unlock();
if (!neigh_node)
neigh_node = batadv_iv_ogm_neigh_new(if_incoming,
orig_neigh_node->orig,
orig_neigh_node,
orig_neigh_node,
batman_ogm_packet->seqno);
if (!neigh_node)
goto out;
/* if orig_node is direct neighbor update neigh_node last_seen */
if (orig_node == orig_neigh_node)
neigh_node->last_seen = jiffies;
orig_node->last_seen = jiffies;
/* find packet count of corresponding one hop neighbor */
spin_lock_bh(&orig_node->ogm_cnt_lock);
orig_eq_count = orig_neigh_node->bcast_own_sum[if_incoming->if_num];
neigh_rq_count = neigh_node->real_packet_count;
spin_unlock_bh(&orig_node->ogm_cnt_lock);
/* pay attention to not get a value bigger than 100 % */
total_count = (orig_eq_count > neigh_rq_count ?
neigh_rq_count : orig_eq_count);
/* if we have too few packets (too less data) we set tq_own to zero
* if we receive too few packets it is not considered bidirectional
*/
if ((total_count < TQ_LOCAL_BIDRECT_SEND_MINIMUM) ||
(neigh_rq_count < TQ_LOCAL_BIDRECT_RECV_MINIMUM))
tq_own = 0;
else
/* neigh_node->real_packet_count is never zero as we
* only purge old information when getting new
* information
*/
tq_own = (TQ_MAX_VALUE * total_count) / neigh_rq_count;
/* 1 - ((1-x) ** 3), normalized to TQ_MAX_VALUE this does
* affect the nearly-symmetric links only a little, but
* punishes asymmetric links more. This will give a value
* between 0 and TQ_MAX_VALUE
*/
tq_asym_penalty = TQ_MAX_VALUE - (TQ_MAX_VALUE *
(TQ_LOCAL_WINDOW_SIZE - neigh_rq_count) *
(TQ_LOCAL_WINDOW_SIZE - neigh_rq_count) *
(TQ_LOCAL_WINDOW_SIZE - neigh_rq_count)) /
(TQ_LOCAL_WINDOW_SIZE *
TQ_LOCAL_WINDOW_SIZE *
TQ_LOCAL_WINDOW_SIZE);
batman_ogm_packet->tq = ((batman_ogm_packet->tq * tq_own
* tq_asym_penalty) /
(TQ_MAX_VALUE * TQ_MAX_VALUE));
batadv_dbg(DBG_BATMAN, bat_priv,
"bidirectional: orig = %-15pM neigh = %-15pM => own_bcast = %2i, real recv = %2i, local tq: %3i, asym_penalty: %3i, total tq: %3i\n",
orig_node->orig, orig_neigh_node->orig, total_count,
neigh_rq_count, tq_own,
tq_asym_penalty, batman_ogm_packet->tq);
/* if link has the minimum required transmission quality
* consider it bidirectional
*/
if (batman_ogm_packet->tq >= TQ_TOTAL_BIDRECT_LIMIT)
ret = 1;
out:
if (neigh_node)
batadv_neigh_node_free_ref(neigh_node);
return ret;
}
/* processes a batman packet for all interfaces, adjusts the sequence number and
* finds out whether it is a duplicate.
* returns:
* 1 the packet is a duplicate
* 0 the packet has not yet been received
* -1 the packet is old and has been received while the seqno window
* was protected. Caller should drop it.
*/
static int
batadv_iv_ogm_update_seqnos(const struct ethhdr *ethhdr,
const struct batman_ogm_packet *batman_ogm_packet,
const struct hard_iface *if_incoming)
{
struct bat_priv *bat_priv = netdev_priv(if_incoming->soft_iface);
struct orig_node *orig_node;
struct neigh_node *tmp_neigh_node;
struct hlist_node *node;
int is_duplicate = 0;
int32_t seq_diff;
int need_update = 0;
int set_mark, ret = -1;
uint32_t seqno = ntohl(batman_ogm_packet->seqno);
uint8_t *neigh_addr;
orig_node = batadv_get_orig_node(bat_priv, batman_ogm_packet->orig);
if (!orig_node)
return 0;
spin_lock_bh(&orig_node->ogm_cnt_lock);
seq_diff = seqno - orig_node->last_real_seqno;
/* signalize caller that the packet is to be dropped. */
if (!hlist_empty(&orig_node->neigh_list) &&
batadv_window_protected(bat_priv, seq_diff,
&orig_node->batman_seqno_reset))
goto out;
rcu_read_lock();
hlist_for_each_entry_rcu(tmp_neigh_node, node,
&orig_node->neigh_list, list) {
is_duplicate |= batadv_test_bit(tmp_neigh_node->real_bits,
orig_node->last_real_seqno,
seqno);
neigh_addr = tmp_neigh_node->addr;
if (batadv_compare_eth(neigh_addr, ethhdr->h_source) &&
tmp_neigh_node->if_incoming == if_incoming)
set_mark = 1;
else
set_mark = 0;
/* if the window moved, set the update flag. */
need_update |= batadv_bit_get_packet(bat_priv,
tmp_neigh_node->real_bits,
seq_diff, set_mark);
tmp_neigh_node->real_packet_count =
bitmap_weight(tmp_neigh_node->real_bits,
TQ_LOCAL_WINDOW_SIZE);
}
rcu_read_unlock();
if (need_update) {
batadv_dbg(DBG_BATMAN, bat_priv,
"updating last_seqno: old %u, new %u\n",
orig_node->last_real_seqno, seqno);
orig_node->last_real_seqno = seqno;
}
ret = is_duplicate;
out:
spin_unlock_bh(&orig_node->ogm_cnt_lock);
batadv_orig_node_free_ref(orig_node);
return ret;
}
static void batadv_iv_ogm_process(const struct ethhdr *ethhdr,
struct batman_ogm_packet *batman_ogm_packet,
const unsigned char *tt_buff,
struct hard_iface *if_incoming)
{
struct bat_priv *bat_priv = netdev_priv(if_incoming->soft_iface);
struct hard_iface *hard_iface;
struct orig_node *orig_neigh_node, *orig_node;
struct neigh_node *router = NULL, *router_router = NULL;
struct neigh_node *orig_neigh_router = NULL;
int has_directlink_flag;
int is_my_addr = 0, is_my_orig = 0, is_my_oldorig = 0;
int is_broadcast = 0, is_bidirect;
bool is_single_hop_neigh = false;
bool is_from_best_next_hop = false;
int is_duplicate, sameseq, simlar_ttl;
uint32_t if_incoming_seqno;
uint8_t *prev_sender;
/* Silently drop when the batman packet is actually not a
* correct packet.
*
* This might happen if a packet is padded (e.g. Ethernet has a
* minimum frame length of 64 byte) and the aggregation interprets
* it as an additional length.
*
* TODO: A more sane solution would be to have a bit in the
* batman_ogm_packet to detect whether the packet is the last
* packet in an aggregation. Here we expect that the padding
* is always zero (or not 0x01)
*/
if (batman_ogm_packet->header.packet_type != BAT_IV_OGM)
return;
/* could be changed by schedule_own_packet() */
if_incoming_seqno = atomic_read(&if_incoming->seqno);
has_directlink_flag = (batman_ogm_packet->flags & DIRECTLINK ? 1 : 0);
if (batadv_compare_eth(ethhdr->h_source, batman_ogm_packet->orig))
is_single_hop_neigh = true;
batadv_dbg(DBG_BATMAN, bat_priv,
"Received BATMAN packet via NB: %pM, IF: %s [%pM] (from OG: %pM, via prev OG: %pM, seqno %u, ttvn %u, crc %u, changes %u, td %d, TTL %d, V %d, IDF %d)\n",
ethhdr->h_source, if_incoming->net_dev->name,
if_incoming->net_dev->dev_addr, batman_ogm_packet->orig,
batman_ogm_packet->prev_sender,
ntohl(batman_ogm_packet->seqno), batman_ogm_packet->ttvn,
ntohs(batman_ogm_packet->tt_crc),
batman_ogm_packet->tt_num_changes, batman_ogm_packet->tq,
batman_ogm_packet->header.ttl,
batman_ogm_packet->header.version, has_directlink_flag);
rcu_read_lock();
list_for_each_entry_rcu(hard_iface, &batadv_hardif_list, list) {
if (hard_iface->if_status != IF_ACTIVE)
continue;
if (hard_iface->soft_iface != if_incoming->soft_iface)
continue;
if (batadv_compare_eth(ethhdr->h_source,
hard_iface->net_dev->dev_addr))
is_my_addr = 1;
if (batadv_compare_eth(batman_ogm_packet->orig,
hard_iface->net_dev->dev_addr))
is_my_orig = 1;
if (batadv_compare_eth(batman_ogm_packet->prev_sender,
hard_iface->net_dev->dev_addr))
is_my_oldorig = 1;
if (is_broadcast_ether_addr(ethhdr->h_source))
is_broadcast = 1;
}
rcu_read_unlock();
if (batman_ogm_packet->header.version != COMPAT_VERSION) {
batadv_dbg(DBG_BATMAN, bat_priv,
"Drop packet: incompatible batman version (%i)\n",
batman_ogm_packet->header.version);
return;
}
if (is_my_addr) {
batadv_dbg(DBG_BATMAN, bat_priv,
"Drop packet: received my own broadcast (sender: %pM)\n",
ethhdr->h_source);
return;
}
if (is_broadcast) {
batadv_dbg(DBG_BATMAN, bat_priv,
"Drop packet: ignoring all packets with broadcast source addr (sender: %pM)\n",
ethhdr->h_source);
return;
}
if (is_my_orig) {
unsigned long *word;
int offset;
int32_t bit_pos;
orig_neigh_node = batadv_get_orig_node(bat_priv,
ethhdr->h_source);
if (!orig_neigh_node)
return;
/* neighbor has to indicate direct link and it has to
* come via the corresponding interface
* save packet seqno for bidirectional check
*/
if (has_directlink_flag &&
batadv_compare_eth(if_incoming->net_dev->dev_addr,
batman_ogm_packet->orig)) {
offset = if_incoming->if_num * NUM_WORDS;
spin_lock_bh(&orig_neigh_node->ogm_cnt_lock);
word = &(orig_neigh_node->bcast_own[offset]);
bit_pos = if_incoming_seqno - 2;
bit_pos -= ntohl(batman_ogm_packet->seqno);
batadv_set_bit(word, bit_pos);
orig_neigh_node->bcast_own_sum[if_incoming->if_num] =
bitmap_weight(word, TQ_LOCAL_WINDOW_SIZE);
spin_unlock_bh(&orig_neigh_node->ogm_cnt_lock);
}
batadv_dbg(DBG_BATMAN, bat_priv,
"Drop packet: originator packet from myself (via neighbor)\n");
batadv_orig_node_free_ref(orig_neigh_node);
return;
}
if (is_my_oldorig) {
batadv_dbg(DBG_BATMAN, bat_priv,
"Drop packet: ignoring all rebroadcast echos (sender: %pM)\n",
ethhdr->h_source);
return;
}
if (batman_ogm_packet->flags & NOT_BEST_NEXT_HOP) {
batadv_dbg(DBG_BATMAN, bat_priv,
"Drop packet: ignoring all packets not forwarded from the best next hop (sender: %pM)\n",
ethhdr->h_source);
return;
}
orig_node = batadv_get_orig_node(bat_priv, batman_ogm_packet->orig);
if (!orig_node)
return;
is_duplicate = batadv_iv_ogm_update_seqnos(ethhdr, batman_ogm_packet,
if_incoming);
if (is_duplicate == -1) {
batadv_dbg(DBG_BATMAN, bat_priv,
"Drop packet: packet within seqno protection time (sender: %pM)\n",
ethhdr->h_source);
goto out;
}
if (batman_ogm_packet->tq == 0) {
batadv_dbg(DBG_BATMAN, bat_priv,
"Drop packet: originator packet with tq equal 0\n");
goto out;
}
router = batadv_orig_node_get_router(orig_node);
if (router)
router_router = batadv_orig_node_get_router(router->orig_node);
if ((router && router->tq_avg != 0) &&
(batadv_compare_eth(router->addr, ethhdr->h_source)))
is_from_best_next_hop = true;
prev_sender = batman_ogm_packet->prev_sender;
/* avoid temporary routing loops */
if (router && router_router &&
(batadv_compare_eth(router->addr, prev_sender)) &&
!(batadv_compare_eth(batman_ogm_packet->orig, prev_sender)) &&
(batadv_compare_eth(router->addr, router_router->addr))) {
batadv_dbg(DBG_BATMAN, bat_priv,
"Drop packet: ignoring all rebroadcast packets that may make me loop (sender: %pM)\n",
ethhdr->h_source);
goto out;
}
/* if sender is a direct neighbor the sender mac equals
* originator mac
*/
orig_neigh_node = (is_single_hop_neigh ?
orig_node :
batadv_get_orig_node(bat_priv, ethhdr->h_source));
if (!orig_neigh_node)
goto out;
orig_neigh_router = batadv_orig_node_get_router(orig_neigh_node);
/* drop packet if sender is not a direct neighbor and if we
* don't route towards it
*/
if (!is_single_hop_neigh && (!orig_neigh_router)) {
batadv_dbg(DBG_BATMAN, bat_priv,
"Drop packet: OGM via unknown neighbor!\n");
goto out_neigh;
}
is_bidirect = batadv_iv_ogm_calc_tq(orig_node, orig_neigh_node,
batman_ogm_packet, if_incoming);
batadv_bonding_save_primary(orig_node, orig_neigh_node,
batman_ogm_packet);
/* update ranking if it is not a duplicate or has the same
* seqno and similar ttl as the non-duplicate
*/
sameseq = orig_node->last_real_seqno == ntohl(batman_ogm_packet->seqno);
simlar_ttl = orig_node->last_ttl - 3 <= batman_ogm_packet->header.ttl;
if (is_bidirect && (!is_duplicate || (sameseq && simlar_ttl)))
batadv_iv_ogm_orig_update(bat_priv, orig_node, ethhdr,
batman_ogm_packet, if_incoming,
tt_buff, is_duplicate);
/* is single hop (direct) neighbor */
if (is_single_hop_neigh) {
/* mark direct link on incoming interface */
batadv_iv_ogm_forward(orig_node, ethhdr, batman_ogm_packet,
is_single_hop_neigh,
is_from_best_next_hop, if_incoming);
batadv_dbg(DBG_BATMAN, bat_priv,
"Forwarding packet: rebroadcast neighbor packet with direct link flag\n");
goto out_neigh;
}
/* multihop originator */
if (!is_bidirect) {
batadv_dbg(DBG_BATMAN, bat_priv,
"Drop packet: not received via bidirectional link\n");
goto out_neigh;
}
if (is_duplicate) {
batadv_dbg(DBG_BATMAN, bat_priv,
"Drop packet: duplicate packet received\n");
goto out_neigh;
}
batadv_dbg(DBG_BATMAN, bat_priv,
"Forwarding packet: rebroadcast originator packet\n");
batadv_iv_ogm_forward(orig_node, ethhdr, batman_ogm_packet,
is_single_hop_neigh, is_from_best_next_hop,
if_incoming);
out_neigh:
if ((orig_neigh_node) && (!is_single_hop_neigh))
batadv_orig_node_free_ref(orig_neigh_node);
out:
if (router)
batadv_neigh_node_free_ref(router);
if (router_router)
batadv_neigh_node_free_ref(router_router);
if (orig_neigh_router)
batadv_neigh_node_free_ref(orig_neigh_router);
batadv_orig_node_free_ref(orig_node);
}
static int batadv_iv_ogm_receive(struct sk_buff *skb,
struct hard_iface *if_incoming)
{
struct bat_priv *bat_priv = netdev_priv(if_incoming->soft_iface);
struct batman_ogm_packet *batman_ogm_packet;
struct ethhdr *ethhdr;
int buff_pos = 0, packet_len;
unsigned char *tt_buff, *packet_buff;
bool ret;
ret = batadv_check_management_packet(skb, if_incoming, BATMAN_OGM_HLEN);
if (!ret)
return NET_RX_DROP;
/* did we receive a B.A.T.M.A.N. IV OGM packet on an interface
* that does not have B.A.T.M.A.N. IV enabled ?
*/
if (bat_priv->bat_algo_ops->bat_ogm_emit != batadv_iv_ogm_emit)
return NET_RX_DROP;
batadv_inc_counter(bat_priv, BAT_CNT_MGMT_RX);
batadv_add_counter(bat_priv, BAT_CNT_MGMT_RX_BYTES,
skb->len + ETH_HLEN);
packet_len = skb_headlen(skb);
ethhdr = (struct ethhdr *)skb_mac_header(skb);
packet_buff = skb->data;
batman_ogm_packet = (struct batman_ogm_packet *)packet_buff;
/* unpack the aggregated packets and process them one by one */
do {
tt_buff = packet_buff + buff_pos + BATMAN_OGM_HLEN;
batadv_iv_ogm_process(ethhdr, batman_ogm_packet, tt_buff,
if_incoming);
buff_pos += BATMAN_OGM_HLEN;
buff_pos += batadv_tt_len(batman_ogm_packet->tt_num_changes);
batman_ogm_packet = (struct batman_ogm_packet *)
(packet_buff + buff_pos);
} while (batadv_iv_ogm_aggr_packet(buff_pos, packet_len,
batman_ogm_packet->tt_num_changes));
kfree_skb(skb);
return NET_RX_SUCCESS;
}
static struct bat_algo_ops batadv_batman_iv __read_mostly = {
.name = "BATMAN_IV",
.bat_iface_enable = batadv_iv_ogm_iface_enable,
.bat_iface_disable = batadv_iv_ogm_iface_disable,
.bat_iface_update_mac = batadv_iv_ogm_iface_update_mac,
.bat_primary_iface_set = batadv_iv_ogm_primary_iface_set,
.bat_ogm_schedule = batadv_iv_ogm_schedule,
.bat_ogm_emit = batadv_iv_ogm_emit,
};
int __init batadv_iv_init(void)
{
int ret;
/* batman originator packet */
ret = batadv_recv_handler_register(BAT_IV_OGM, batadv_iv_ogm_receive);
if (ret < 0)
goto out;
ret = batadv_algo_register(&batadv_batman_iv);
if (ret < 0)
goto handler_unregister;
goto out;
handler_unregister:
batadv_recv_handler_unregister(BAT_IV_OGM);
out:
return ret;
}
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