linux/net/batman-adv/routing.c

1536 lines
40 KiB
C

/*
* Copyright (C) 2007-2011 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 "routing.h"
#include "send.h"
#include "hash.h"
#include "soft-interface.h"
#include "hard-interface.h"
#include "icmp_socket.h"
#include "translation-table.h"
#include "originator.h"
#include "ring_buffer.h"
#include "vis.h"
#include "aggregation.h"
#include "gateway_common.h"
#include "gateway_client.h"
#include "unicast.h"
void slide_own_bcast_window(struct hard_iface *hard_iface)
{
struct bat_priv *bat_priv = netdev_priv(hard_iface->soft_iface);
struct hashtable_t *hash = bat_priv->orig_hash;
struct hlist_node *node;
struct hlist_head *head;
struct orig_node *orig_node;
unsigned long *word;
int i;
size_t word_index;
for (i = 0; i < hash->size; i++) {
head = &hash->table[i];
rcu_read_lock();
hlist_for_each_entry_rcu(orig_node, node, head, hash_entry) {
spin_lock_bh(&orig_node->ogm_cnt_lock);
word_index = hard_iface->if_num * NUM_WORDS;
word = &(orig_node->bcast_own[word_index]);
bit_get_packet(bat_priv, word, 1, 0);
orig_node->bcast_own_sum[hard_iface->if_num] =
bit_packet_count(word);
spin_unlock_bh(&orig_node->ogm_cnt_lock);
}
rcu_read_unlock();
}
}
static void update_HNA(struct bat_priv *bat_priv, struct orig_node *orig_node,
unsigned char *hna_buff, int hna_buff_len)
{
if ((hna_buff_len != orig_node->hna_buff_len) ||
((hna_buff_len > 0) &&
(orig_node->hna_buff_len > 0) &&
(memcmp(orig_node->hna_buff, hna_buff, hna_buff_len) != 0))) {
if (orig_node->hna_buff_len > 0)
hna_global_del_orig(bat_priv, orig_node,
"originator changed hna");
if ((hna_buff_len > 0) && (hna_buff))
hna_global_add_orig(bat_priv, orig_node,
hna_buff, hna_buff_len);
}
}
static void update_route(struct bat_priv *bat_priv,
struct orig_node *orig_node,
struct neigh_node *neigh_node,
unsigned char *hna_buff, int hna_buff_len)
{
struct neigh_node *neigh_node_tmp;
/* route deleted */
if ((orig_node->router) && (!neigh_node)) {
bat_dbg(DBG_ROUTES, bat_priv, "Deleting route towards: %pM\n",
orig_node->orig);
hna_global_del_orig(bat_priv, orig_node,
"originator timed out");
/* route added */
} else if ((!orig_node->router) && (neigh_node)) {
bat_dbg(DBG_ROUTES, bat_priv,
"Adding route towards: %pM (via %pM)\n",
orig_node->orig, neigh_node->addr);
hna_global_add_orig(bat_priv, orig_node,
hna_buff, hna_buff_len);
/* route changed */
} else {
bat_dbg(DBG_ROUTES, bat_priv,
"Changing route towards: %pM "
"(now via %pM - was via %pM)\n",
orig_node->orig, neigh_node->addr,
orig_node->router->addr);
}
if (neigh_node && !atomic_inc_not_zero(&neigh_node->refcount))
neigh_node = NULL;
neigh_node_tmp = orig_node->router;
orig_node->router = neigh_node;
if (neigh_node_tmp)
neigh_node_free_ref(neigh_node_tmp);
}
void update_routes(struct bat_priv *bat_priv, struct orig_node *orig_node,
struct neigh_node *neigh_node, unsigned char *hna_buff,
int hna_buff_len)
{
if (!orig_node)
return;
if (orig_node->router != neigh_node)
update_route(bat_priv, orig_node, neigh_node,
hna_buff, hna_buff_len);
/* may be just HNA changed */
else
update_HNA(bat_priv, orig_node, hna_buff, hna_buff_len);
}
static int is_bidirectional_neigh(struct orig_node *orig_node,
struct orig_node *orig_neigh_node,
struct batman_packet *batman_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;
unsigned char total_count;
uint8_t orig_eq_count, neigh_rq_count, tq_own;
int tq_asym_penalty, ret = 0;
if (orig_node == orig_neigh_node) {
rcu_read_lock();
hlist_for_each_entry_rcu(tmp_neigh_node, node,
&orig_node->neigh_list, list) {
if (!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;
}
rcu_read_unlock();
if (!neigh_node)
neigh_node = create_neighbor(orig_node,
orig_neigh_node,
orig_neigh_node->orig,
if_incoming);
if (!neigh_node)
goto out;
neigh_node->last_valid = jiffies;
} else {
/* find packet count of corresponding one hop neighbor */
rcu_read_lock();
hlist_for_each_entry_rcu(tmp_neigh_node, node,
&orig_neigh_node->neigh_list, list) {
if (!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;
}
rcu_read_unlock();
if (!neigh_node)
neigh_node = create_neighbor(orig_neigh_node,
orig_neigh_node,
orig_neigh_node->orig,
if_incoming);
if (!neigh_node)
goto out;
}
orig_node->last_valid = jiffies;
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_packet->tq = ((batman_packet->tq * tq_own * tq_asym_penalty) /
(TQ_MAX_VALUE * TQ_MAX_VALUE));
bat_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_packet->tq);
/* if link has the minimum required transmission quality
* consider it bidirectional */
if (batman_packet->tq >= TQ_TOTAL_BIDRECT_LIMIT)
ret = 1;
out:
if (neigh_node)
neigh_node_free_ref(neigh_node);
return ret;
}
/* caller must hold the neigh_list_lock */
void bonding_candidate_del(struct orig_node *orig_node,
struct neigh_node *neigh_node)
{
/* this neighbor is not part of our candidate list */
if (list_empty(&neigh_node->bonding_list))
goto out;
list_del_rcu(&neigh_node->bonding_list);
INIT_LIST_HEAD(&neigh_node->bonding_list);
neigh_node_free_ref(neigh_node);
atomic_dec(&orig_node->bond_candidates);
out:
return;
}
static void bonding_candidate_add(struct orig_node *orig_node,
struct neigh_node *neigh_node)
{
struct hlist_node *node;
struct neigh_node *tmp_neigh_node;
uint8_t best_tq, interference_candidate = 0;
spin_lock_bh(&orig_node->neigh_list_lock);
/* only consider if it has the same primary address ... */
if (!compare_eth(orig_node->orig,
neigh_node->orig_node->primary_addr))
goto candidate_del;
if (!orig_node->router)
goto candidate_del;
best_tq = orig_node->router->tq_avg;
/* ... and is good enough to be considered */
if (neigh_node->tq_avg < best_tq - BONDING_TQ_THRESHOLD)
goto candidate_del;
/**
* check if we have another candidate with the same mac address or
* interface. If we do, we won't select this candidate because of
* possible interference.
*/
hlist_for_each_entry_rcu(tmp_neigh_node, node,
&orig_node->neigh_list, list) {
if (tmp_neigh_node == neigh_node)
continue;
/* we only care if the other candidate is even
* considered as candidate. */
if (list_empty(&tmp_neigh_node->bonding_list))
continue;
if ((neigh_node->if_incoming == tmp_neigh_node->if_incoming) ||
(compare_eth(neigh_node->addr, tmp_neigh_node->addr))) {
interference_candidate = 1;
break;
}
}
/* don't care further if it is an interference candidate */
if (interference_candidate)
goto candidate_del;
/* this neighbor already is part of our candidate list */
if (!list_empty(&neigh_node->bonding_list))
goto out;
if (!atomic_inc_not_zero(&neigh_node->refcount))
goto out;
list_add_rcu(&neigh_node->bonding_list, &orig_node->bond_list);
atomic_inc(&orig_node->bond_candidates);
goto out;
candidate_del:
bonding_candidate_del(orig_node, neigh_node);
out:
spin_unlock_bh(&orig_node->neigh_list_lock);
return;
}
/* copy primary address for bonding */
static void bonding_save_primary(struct orig_node *orig_node,
struct orig_node *orig_neigh_node,
struct batman_packet *batman_packet)
{
if (!(batman_packet->flags & PRIMARIES_FIRST_HOP))
return;
memcpy(orig_neigh_node->primary_addr, orig_node->orig, ETH_ALEN);
}
static void update_orig(struct bat_priv *bat_priv,
struct orig_node *orig_node,
struct ethhdr *ethhdr,
struct batman_packet *batman_packet,
struct hard_iface *if_incoming,
unsigned char *hna_buff, int hna_buff_len,
char is_duplicate)
{
struct neigh_node *neigh_node = NULL, *tmp_neigh_node = NULL;
struct orig_node *orig_node_tmp;
struct hlist_node *node;
int tmp_hna_buff_len;
uint8_t bcast_own_sum_orig, bcast_own_sum_neigh;
bat_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) {
if (compare_eth(tmp_neigh_node->addr, ethhdr->h_source) &&
(tmp_neigh_node->if_incoming == if_incoming) &&
atomic_inc_not_zero(&tmp_neigh_node->refcount)) {
if (neigh_node)
neigh_node_free_ref(neigh_node);
neigh_node = tmp_neigh_node;
continue;
}
if (is_duplicate)
continue;
ring_buffer_set(tmp_neigh_node->tq_recv,
&tmp_neigh_node->tq_index, 0);
tmp_neigh_node->tq_avg =
ring_buffer_avg(tmp_neigh_node->tq_recv);
}
if (!neigh_node) {
struct orig_node *orig_tmp;
orig_tmp = get_orig_node(bat_priv, ethhdr->h_source);
if (!orig_tmp)
goto unlock;
neigh_node = create_neighbor(orig_node, orig_tmp,
ethhdr->h_source, if_incoming);
orig_node_free_ref(orig_tmp);
if (!neigh_node)
goto unlock;
} else
bat_dbg(DBG_BATMAN, bat_priv,
"Updating existing last-hop neighbor of originator\n");
rcu_read_unlock();
orig_node->flags = batman_packet->flags;
neigh_node->last_valid = jiffies;
ring_buffer_set(neigh_node->tq_recv,
&neigh_node->tq_index,
batman_packet->tq);
neigh_node->tq_avg = ring_buffer_avg(neigh_node->tq_recv);
if (!is_duplicate) {
orig_node->last_ttl = batman_packet->ttl;
neigh_node->last_ttl = batman_packet->ttl;
}
bonding_candidate_add(orig_node, neigh_node);
tmp_hna_buff_len = (hna_buff_len > batman_packet->num_hna * ETH_ALEN ?
batman_packet->num_hna * ETH_ALEN : hna_buff_len);
/* if this neighbor already is our next hop there is nothing
* to change */
if (orig_node->router == neigh_node)
goto update_hna;
/* if this neighbor does not offer a better TQ we won't consider it */
if ((orig_node->router) &&
(orig_node->router->tq_avg > neigh_node->tq_avg))
goto update_hna;
/* if the TQ is the same and the link not more symetric we
* won't consider it either */
if ((orig_node->router) &&
(neigh_node->tq_avg == orig_node->router->tq_avg)) {
orig_node_tmp = orig_node->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_hna;
}
update_routes(bat_priv, orig_node, neigh_node,
hna_buff, tmp_hna_buff_len);
goto update_gw;
update_hna:
update_routes(bat_priv, orig_node, orig_node->router,
hna_buff, tmp_hna_buff_len);
update_gw:
if (orig_node->gw_flags != batman_packet->gw_flags)
gw_node_update(bat_priv, orig_node, batman_packet->gw_flags);
orig_node->gw_flags = batman_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))
gw_check_election(bat_priv, orig_node);
goto out;
unlock:
rcu_read_unlock();
out:
if (neigh_node)
neigh_node_free_ref(neigh_node);
}
/* checks whether the host restarted and is in the protection time.
* returns:
* 0 if the packet is to be accepted
* 1 if the packet is to be ignored.
*/
static int window_protected(struct bat_priv *bat_priv,
int32_t seq_num_diff,
unsigned long *last_reset)
{
if ((seq_num_diff <= -TQ_LOCAL_WINDOW_SIZE)
|| (seq_num_diff >= EXPECTED_SEQNO_RANGE)) {
if (time_after(jiffies, *last_reset +
msecs_to_jiffies(RESET_PROTECTION_MS))) {
*last_reset = jiffies;
bat_dbg(DBG_BATMAN, bat_priv,
"old packet received, start protection\n");
return 0;
} else
return 1;
}
return 0;
}
/* 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 char count_real_packets(struct ethhdr *ethhdr,
struct batman_packet *batman_packet,
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;
char is_duplicate = 0;
int32_t seq_diff;
int need_update = 0;
int set_mark, ret = -1;
orig_node = get_orig_node(bat_priv, batman_packet->orig);
if (!orig_node)
return 0;
spin_lock_bh(&orig_node->ogm_cnt_lock);
seq_diff = batman_packet->seqno - orig_node->last_real_seqno;
/* signalize caller that the packet is to be dropped. */
if (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 |= get_bit_status(tmp_neigh_node->real_bits,
orig_node->last_real_seqno,
batman_packet->seqno);
if (compare_eth(tmp_neigh_node->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 |= bit_get_packet(bat_priv,
tmp_neigh_node->real_bits,
seq_diff, set_mark);
tmp_neigh_node->real_packet_count =
bit_packet_count(tmp_neigh_node->real_bits);
}
rcu_read_unlock();
if (need_update) {
bat_dbg(DBG_BATMAN, bat_priv,
"updating last_seqno: old %d, new %d\n",
orig_node->last_real_seqno, batman_packet->seqno);
orig_node->last_real_seqno = batman_packet->seqno;
}
ret = is_duplicate;
out:
spin_unlock_bh(&orig_node->ogm_cnt_lock);
orig_node_free_ref(orig_node);
return ret;
}
void receive_bat_packet(struct ethhdr *ethhdr,
struct batman_packet *batman_packet,
unsigned char *hna_buff, int hna_buff_len,
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;
char has_directlink_flag;
char is_my_addr = 0, is_my_orig = 0, is_my_oldorig = 0;
char is_broadcast = 0, is_bidirectional, is_single_hop_neigh;
char is_duplicate;
uint32_t if_incoming_seqno;
/* 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_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_packet->packet_type != BAT_PACKET)
return;
/* could be changed by schedule_own_packet() */
if_incoming_seqno = atomic_read(&if_incoming->seqno);
has_directlink_flag = (batman_packet->flags & DIRECTLINK ? 1 : 0);
is_single_hop_neigh = (compare_eth(ethhdr->h_source,
batman_packet->orig) ? 1 : 0);
bat_dbg(DBG_BATMAN, bat_priv,
"Received BATMAN packet via NB: %pM, IF: %s [%pM] "
"(from OG: %pM, via prev OG: %pM, seqno %d, tq %d, "
"TTL %d, V %d, IDF %d)\n",
ethhdr->h_source, if_incoming->net_dev->name,
if_incoming->net_dev->dev_addr, batman_packet->orig,
batman_packet->prev_sender, batman_packet->seqno,
batman_packet->tq, batman_packet->ttl, batman_packet->version,
has_directlink_flag);
rcu_read_lock();
list_for_each_entry_rcu(hard_iface, &hardif_list, list) {
if (hard_iface->if_status != IF_ACTIVE)
continue;
if (hard_iface->soft_iface != if_incoming->soft_iface)
continue;
if (compare_eth(ethhdr->h_source,
hard_iface->net_dev->dev_addr))
is_my_addr = 1;
if (compare_eth(batman_packet->orig,
hard_iface->net_dev->dev_addr))
is_my_orig = 1;
if (compare_eth(batman_packet->prev_sender,
hard_iface->net_dev->dev_addr))
is_my_oldorig = 1;
if (compare_eth(ethhdr->h_source, broadcast_addr))
is_broadcast = 1;
}
rcu_read_unlock();
if (batman_packet->version != COMPAT_VERSION) {
bat_dbg(DBG_BATMAN, bat_priv,
"Drop packet: incompatible batman version (%i)\n",
batman_packet->version);
return;
}
if (is_my_addr) {
bat_dbg(DBG_BATMAN, bat_priv,
"Drop packet: received my own broadcast (sender: %pM"
")\n",
ethhdr->h_source);
return;
}
if (is_broadcast) {
bat_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;
orig_neigh_node = 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 */
/* if received seqno equals last send seqno save new
* seqno for bidirectional check */
if (has_directlink_flag &&
compare_eth(if_incoming->net_dev->dev_addr,
batman_packet->orig) &&
(batman_packet->seqno - if_incoming_seqno + 2 == 0)) {
offset = if_incoming->if_num * NUM_WORDS;
spin_lock_bh(&orig_neigh_node->ogm_cnt_lock);
word = &(orig_neigh_node->bcast_own[offset]);
bit_mark(word, 0);
orig_neigh_node->bcast_own_sum[if_incoming->if_num] =
bit_packet_count(word);
spin_unlock_bh(&orig_neigh_node->ogm_cnt_lock);
}
bat_dbg(DBG_BATMAN, bat_priv, "Drop packet: "
"originator packet from myself (via neighbor)\n");
orig_node_free_ref(orig_neigh_node);
return;
}
if (is_my_oldorig) {
bat_dbg(DBG_BATMAN, bat_priv,
"Drop packet: ignoring all rebroadcast echos (sender: "
"%pM)\n", ethhdr->h_source);
return;
}
orig_node = get_orig_node(bat_priv, batman_packet->orig);
if (!orig_node)
return;
is_duplicate = count_real_packets(ethhdr, batman_packet, if_incoming);
if (is_duplicate == -1) {
bat_dbg(DBG_BATMAN, bat_priv,
"Drop packet: packet within seqno protection time "
"(sender: %pM)\n", ethhdr->h_source);
goto out;
}
if (batman_packet->tq == 0) {
bat_dbg(DBG_BATMAN, bat_priv,
"Drop packet: originator packet with tq equal 0\n");
goto out;
}
/* avoid temporary routing loops */
if ((orig_node->router) &&
(orig_node->router->orig_node->router) &&
(compare_eth(orig_node->router->addr,
batman_packet->prev_sender)) &&
!(compare_eth(batman_packet->orig, batman_packet->prev_sender)) &&
(compare_eth(orig_node->router->addr,
orig_node->router->orig_node->router->addr))) {
bat_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 :
get_orig_node(bat_priv, ethhdr->h_source));
if (!orig_neigh_node)
goto out;
/* drop packet if sender is not a direct neighbor and if we
* don't route towards it */
if (!is_single_hop_neigh && (!orig_neigh_node->router)) {
bat_dbg(DBG_BATMAN, bat_priv,
"Drop packet: OGM via unknown neighbor!\n");
goto out_neigh;
}
is_bidirectional = is_bidirectional_neigh(orig_node, orig_neigh_node,
batman_packet, if_incoming);
bonding_save_primary(orig_node, orig_neigh_node, batman_packet);
/* update ranking if it is not a duplicate or has the same
* seqno and similar ttl as the non-duplicate */
if (is_bidirectional &&
(!is_duplicate ||
((orig_node->last_real_seqno == batman_packet->seqno) &&
(orig_node->last_ttl - 3 <= batman_packet->ttl))))
update_orig(bat_priv, orig_node, ethhdr, batman_packet,
if_incoming, hna_buff, hna_buff_len, is_duplicate);
/* is single hop (direct) neighbor */
if (is_single_hop_neigh) {
/* mark direct link on incoming interface */
schedule_forward_packet(orig_node, ethhdr, batman_packet,
1, hna_buff_len, if_incoming);
bat_dbg(DBG_BATMAN, bat_priv, "Forwarding packet: "
"rebroadcast neighbor packet with direct link flag\n");
goto out_neigh;
}
/* multihop originator */
if (!is_bidirectional) {
bat_dbg(DBG_BATMAN, bat_priv,
"Drop packet: not received via bidirectional link\n");
goto out_neigh;
}
if (is_duplicate) {
bat_dbg(DBG_BATMAN, bat_priv,
"Drop packet: duplicate packet received\n");
goto out_neigh;
}
bat_dbg(DBG_BATMAN, bat_priv,
"Forwarding packet: rebroadcast originator packet\n");
schedule_forward_packet(orig_node, ethhdr, batman_packet,
0, hna_buff_len, if_incoming);
out_neigh:
if ((orig_neigh_node) && (!is_single_hop_neigh))
orig_node_free_ref(orig_neigh_node);
out:
orig_node_free_ref(orig_node);
}
int recv_bat_packet(struct sk_buff *skb, struct hard_iface *hard_iface)
{
struct ethhdr *ethhdr;
/* drop packet if it has not necessary minimum size */
if (unlikely(!pskb_may_pull(skb, sizeof(struct batman_packet))))
return NET_RX_DROP;
ethhdr = (struct ethhdr *)skb_mac_header(skb);
/* packet with broadcast indication but unicast recipient */
if (!is_broadcast_ether_addr(ethhdr->h_dest))
return NET_RX_DROP;
/* packet with broadcast sender address */
if (is_broadcast_ether_addr(ethhdr->h_source))
return NET_RX_DROP;
/* create a copy of the skb, if needed, to modify it. */
if (skb_cow(skb, 0) < 0)
return NET_RX_DROP;
/* keep skb linear */
if (skb_linearize(skb) < 0)
return NET_RX_DROP;
ethhdr = (struct ethhdr *)skb_mac_header(skb);
receive_aggr_bat_packet(ethhdr,
skb->data,
skb_headlen(skb),
hard_iface);
kfree_skb(skb);
return NET_RX_SUCCESS;
}
static int recv_my_icmp_packet(struct bat_priv *bat_priv,
struct sk_buff *skb, size_t icmp_len)
{
struct orig_node *orig_node = NULL;
struct neigh_node *neigh_node = NULL;
struct icmp_packet_rr *icmp_packet;
int ret = NET_RX_DROP;
icmp_packet = (struct icmp_packet_rr *)skb->data;
/* add data to device queue */
if (icmp_packet->msg_type != ECHO_REQUEST) {
bat_socket_receive_packet(icmp_packet, icmp_len);
goto out;
}
if (!bat_priv->primary_if)
goto out;
/* answer echo request (ping) */
/* get routing information */
rcu_read_lock();
orig_node = orig_hash_find(bat_priv, icmp_packet->orig);
if (!orig_node)
goto unlock;
neigh_node = orig_node->router;
if (!neigh_node)
goto unlock;
if (!atomic_inc_not_zero(&neigh_node->refcount)) {
neigh_node = NULL;
goto unlock;
}
rcu_read_unlock();
/* create a copy of the skb, if needed, to modify it. */
if (skb_cow(skb, sizeof(struct ethhdr)) < 0)
goto out;
icmp_packet = (struct icmp_packet_rr *)skb->data;
memcpy(icmp_packet->dst, icmp_packet->orig, ETH_ALEN);
memcpy(icmp_packet->orig,
bat_priv->primary_if->net_dev->dev_addr, ETH_ALEN);
icmp_packet->msg_type = ECHO_REPLY;
icmp_packet->ttl = TTL;
send_skb_packet(skb, neigh_node->if_incoming, neigh_node->addr);
ret = NET_RX_SUCCESS;
goto out;
unlock:
rcu_read_unlock();
out:
if (neigh_node)
neigh_node_free_ref(neigh_node);
if (orig_node)
orig_node_free_ref(orig_node);
return ret;
}
static int recv_icmp_ttl_exceeded(struct bat_priv *bat_priv,
struct sk_buff *skb)
{
struct orig_node *orig_node = NULL;
struct neigh_node *neigh_node = NULL;
struct icmp_packet *icmp_packet;
int ret = NET_RX_DROP;
icmp_packet = (struct icmp_packet *)skb->data;
/* send TTL exceeded if packet is an echo request (traceroute) */
if (icmp_packet->msg_type != ECHO_REQUEST) {
pr_debug("Warning - can't forward icmp packet from %pM to "
"%pM: ttl exceeded\n", icmp_packet->orig,
icmp_packet->dst);
goto out;
}
if (!bat_priv->primary_if)
goto out;
/* get routing information */
rcu_read_lock();
orig_node = orig_hash_find(bat_priv, icmp_packet->orig);
if (!orig_node)
goto unlock;
neigh_node = orig_node->router;
if (!neigh_node)
goto unlock;
if (!atomic_inc_not_zero(&neigh_node->refcount)) {
neigh_node = NULL;
goto unlock;
}
rcu_read_unlock();
/* create a copy of the skb, if needed, to modify it. */
if (skb_cow(skb, sizeof(struct ethhdr)) < 0)
goto out;
icmp_packet = (struct icmp_packet *)skb->data;
memcpy(icmp_packet->dst, icmp_packet->orig, ETH_ALEN);
memcpy(icmp_packet->orig,
bat_priv->primary_if->net_dev->dev_addr, ETH_ALEN);
icmp_packet->msg_type = TTL_EXCEEDED;
icmp_packet->ttl = TTL;
send_skb_packet(skb, neigh_node->if_incoming, neigh_node->addr);
ret = NET_RX_SUCCESS;
goto out;
unlock:
rcu_read_unlock();
out:
if (neigh_node)
neigh_node_free_ref(neigh_node);
if (orig_node)
orig_node_free_ref(orig_node);
return ret;
}
int recv_icmp_packet(struct sk_buff *skb, struct hard_iface *recv_if)
{
struct bat_priv *bat_priv = netdev_priv(recv_if->soft_iface);
struct icmp_packet_rr *icmp_packet;
struct ethhdr *ethhdr;
struct orig_node *orig_node = NULL;
struct neigh_node *neigh_node = NULL;
int hdr_size = sizeof(struct icmp_packet);
int ret = NET_RX_DROP;
/**
* we truncate all incoming icmp packets if they don't match our size
*/
if (skb->len >= sizeof(struct icmp_packet_rr))
hdr_size = sizeof(struct icmp_packet_rr);
/* drop packet if it has not necessary minimum size */
if (unlikely(!pskb_may_pull(skb, hdr_size)))
goto out;
ethhdr = (struct ethhdr *)skb_mac_header(skb);
/* packet with unicast indication but broadcast recipient */
if (is_broadcast_ether_addr(ethhdr->h_dest))
goto out;
/* packet with broadcast sender address */
if (is_broadcast_ether_addr(ethhdr->h_source))
goto out;
/* not for me */
if (!is_my_mac(ethhdr->h_dest))
goto out;
icmp_packet = (struct icmp_packet_rr *)skb->data;
/* add record route information if not full */
if ((hdr_size == sizeof(struct icmp_packet_rr)) &&
(icmp_packet->rr_cur < BAT_RR_LEN)) {
memcpy(&(icmp_packet->rr[icmp_packet->rr_cur]),
ethhdr->h_dest, ETH_ALEN);
icmp_packet->rr_cur++;
}
/* packet for me */
if (is_my_mac(icmp_packet->dst))
return recv_my_icmp_packet(bat_priv, skb, hdr_size);
/* TTL exceeded */
if (icmp_packet->ttl < 2)
return recv_icmp_ttl_exceeded(bat_priv, skb);
/* get routing information */
rcu_read_lock();
orig_node = orig_hash_find(bat_priv, icmp_packet->dst);
if (!orig_node)
goto unlock;
neigh_node = orig_node->router;
if (!neigh_node)
goto unlock;
if (!atomic_inc_not_zero(&neigh_node->refcount)) {
neigh_node = NULL;
goto unlock;
}
rcu_read_unlock();
/* create a copy of the skb, if needed, to modify it. */
if (skb_cow(skb, sizeof(struct ethhdr)) < 0)
goto out;
icmp_packet = (struct icmp_packet_rr *)skb->data;
/* decrement ttl */
icmp_packet->ttl--;
/* route it */
send_skb_packet(skb, neigh_node->if_incoming, neigh_node->addr);
ret = NET_RX_SUCCESS;
goto out;
unlock:
rcu_read_unlock();
out:
if (neigh_node)
neigh_node_free_ref(neigh_node);
if (orig_node)
orig_node_free_ref(orig_node);
return ret;
}
/* find a suitable router for this originator, and use
* bonding if possible. increases the found neighbors
* refcount.*/
struct neigh_node *find_router(struct bat_priv *bat_priv,
struct orig_node *orig_node,
struct hard_iface *recv_if)
{
struct orig_node *primary_orig_node;
struct orig_node *router_orig;
struct neigh_node *router, *first_candidate, *tmp_neigh_node;
static uint8_t zero_mac[ETH_ALEN] = {0, 0, 0, 0, 0, 0};
int bonding_enabled;
if (!orig_node)
return NULL;
if (!orig_node->router)
return NULL;
/* without bonding, the first node should
* always choose the default router. */
bonding_enabled = atomic_read(&bat_priv->bonding);
rcu_read_lock();
/* select default router to output */
router = orig_node->router;
router_orig = orig_node->router->orig_node;
if (!router_orig || !atomic_inc_not_zero(&router->refcount)) {
rcu_read_unlock();
return NULL;
}
if ((!recv_if) && (!bonding_enabled))
goto return_router;
/* if we have something in the primary_addr, we can search
* for a potential bonding candidate. */
if (compare_eth(router_orig->primary_addr, zero_mac))
goto return_router;
/* find the orig_node which has the primary interface. might
* even be the same as our router_orig in many cases */
if (compare_eth(router_orig->primary_addr, router_orig->orig)) {
primary_orig_node = router_orig;
} else {
primary_orig_node = orig_hash_find(bat_priv,
router_orig->primary_addr);
if (!primary_orig_node)
goto return_router;
orig_node_free_ref(primary_orig_node);
}
/* with less than 2 candidates, we can't do any
* bonding and prefer the original router. */
if (atomic_read(&primary_orig_node->bond_candidates) < 2)
goto return_router;
/* all nodes between should choose a candidate which
* is is not on the interface where the packet came
* in. */
neigh_node_free_ref(router);
first_candidate = NULL;
router = NULL;
if (bonding_enabled) {
/* in the bonding case, send the packets in a round
* robin fashion over the remaining interfaces. */
list_for_each_entry_rcu(tmp_neigh_node,
&primary_orig_node->bond_list, bonding_list) {
if (!first_candidate)
first_candidate = tmp_neigh_node;
/* recv_if == NULL on the first node. */
if (tmp_neigh_node->if_incoming != recv_if &&
atomic_inc_not_zero(&tmp_neigh_node->refcount)) {
router = tmp_neigh_node;
break;
}
}
/* use the first candidate if nothing was found. */
if (!router && first_candidate &&
atomic_inc_not_zero(&first_candidate->refcount))
router = first_candidate;
if (!router) {
rcu_read_unlock();
return NULL;
}
/* selected should point to the next element
* after the current router */
spin_lock_bh(&primary_orig_node->neigh_list_lock);
/* this is a list_move(), which unfortunately
* does not exist as rcu version */
list_del_rcu(&primary_orig_node->bond_list);
list_add_rcu(&primary_orig_node->bond_list,
&router->bonding_list);
spin_unlock_bh(&primary_orig_node->neigh_list_lock);
} else {
/* if bonding is disabled, use the best of the
* remaining candidates which are not using
* this interface. */
list_for_each_entry_rcu(tmp_neigh_node,
&primary_orig_node->bond_list, bonding_list) {
if (!first_candidate)
first_candidate = tmp_neigh_node;
/* recv_if == NULL on the first node. */
if (tmp_neigh_node->if_incoming == recv_if)
continue;
if (!atomic_inc_not_zero(&tmp_neigh_node->refcount))
continue;
/* if we don't have a router yet
* or this one is better, choose it. */
if ((!router) ||
(tmp_neigh_node->tq_avg > router->tq_avg)) {
/* decrement refcount of
* previously selected router */
if (router)
neigh_node_free_ref(router);
router = tmp_neigh_node;
atomic_inc_not_zero(&router->refcount);
}
neigh_node_free_ref(tmp_neigh_node);
}
/* use the first candidate if nothing was found. */
if (!router && first_candidate &&
atomic_inc_not_zero(&first_candidate->refcount))
router = first_candidate;
}
return_router:
rcu_read_unlock();
return router;
}
static int check_unicast_packet(struct sk_buff *skb, int hdr_size)
{
struct ethhdr *ethhdr;
/* drop packet if it has not necessary minimum size */
if (unlikely(!pskb_may_pull(skb, hdr_size)))
return -1;
ethhdr = (struct ethhdr *)skb_mac_header(skb);
/* packet with unicast indication but broadcast recipient */
if (is_broadcast_ether_addr(ethhdr->h_dest))
return -1;
/* packet with broadcast sender address */
if (is_broadcast_ether_addr(ethhdr->h_source))
return -1;
/* not for me */
if (!is_my_mac(ethhdr->h_dest))
return -1;
return 0;
}
int route_unicast_packet(struct sk_buff *skb, struct hard_iface *recv_if)
{
struct bat_priv *bat_priv = netdev_priv(recv_if->soft_iface);
struct orig_node *orig_node = NULL;
struct neigh_node *neigh_node = NULL;
struct unicast_packet *unicast_packet;
struct ethhdr *ethhdr = (struct ethhdr *)skb_mac_header(skb);
int ret = NET_RX_DROP;
struct sk_buff *new_skb;
unicast_packet = (struct unicast_packet *)skb->data;
/* TTL exceeded */
if (unicast_packet->ttl < 2) {
pr_debug("Warning - can't forward unicast packet from %pM to "
"%pM: ttl exceeded\n", ethhdr->h_source,
unicast_packet->dest);
goto out;
}
/* get routing information */
rcu_read_lock();
orig_node = orig_hash_find(bat_priv, unicast_packet->dest);
if (!orig_node)
goto unlock;
rcu_read_unlock();
/* find_router() increases neigh_nodes refcount if found. */
neigh_node = find_router(bat_priv, orig_node, recv_if);
if (!neigh_node)
goto out;
/* create a copy of the skb, if needed, to modify it. */
if (skb_cow(skb, sizeof(struct ethhdr)) < 0)
goto out;
unicast_packet = (struct unicast_packet *)skb->data;
if (unicast_packet->packet_type == BAT_UNICAST &&
atomic_read(&bat_priv->fragmentation) &&
skb->len > neigh_node->if_incoming->net_dev->mtu) {
ret = frag_send_skb(skb, bat_priv,
neigh_node->if_incoming, neigh_node->addr);
goto out;
}
if (unicast_packet->packet_type == BAT_UNICAST_FRAG &&
frag_can_reassemble(skb, neigh_node->if_incoming->net_dev->mtu)) {
ret = frag_reassemble_skb(skb, bat_priv, &new_skb);
if (ret == NET_RX_DROP)
goto out;
/* packet was buffered for late merge */
if (!new_skb) {
ret = NET_RX_SUCCESS;
goto out;
}
skb = new_skb;
unicast_packet = (struct unicast_packet *)skb->data;
}
/* decrement ttl */
unicast_packet->ttl--;
/* route it */
send_skb_packet(skb, neigh_node->if_incoming, neigh_node->addr);
ret = NET_RX_SUCCESS;
goto out;
unlock:
rcu_read_unlock();
out:
if (neigh_node)
neigh_node_free_ref(neigh_node);
if (orig_node)
orig_node_free_ref(orig_node);
return ret;
}
int recv_unicast_packet(struct sk_buff *skb, struct hard_iface *recv_if)
{
struct unicast_packet *unicast_packet;
int hdr_size = sizeof(struct unicast_packet);
if (check_unicast_packet(skb, hdr_size) < 0)
return NET_RX_DROP;
unicast_packet = (struct unicast_packet *)skb->data;
/* packet for me */
if (is_my_mac(unicast_packet->dest)) {
interface_rx(recv_if->soft_iface, skb, recv_if, hdr_size);
return NET_RX_SUCCESS;
}
return route_unicast_packet(skb, recv_if);
}
int recv_ucast_frag_packet(struct sk_buff *skb, struct hard_iface *recv_if)
{
struct bat_priv *bat_priv = netdev_priv(recv_if->soft_iface);
struct unicast_frag_packet *unicast_packet;
int hdr_size = sizeof(struct unicast_frag_packet);
struct sk_buff *new_skb = NULL;
int ret;
if (check_unicast_packet(skb, hdr_size) < 0)
return NET_RX_DROP;
unicast_packet = (struct unicast_frag_packet *)skb->data;
/* packet for me */
if (is_my_mac(unicast_packet->dest)) {
ret = frag_reassemble_skb(skb, bat_priv, &new_skb);
if (ret == NET_RX_DROP)
return NET_RX_DROP;
/* packet was buffered for late merge */
if (!new_skb)
return NET_RX_SUCCESS;
interface_rx(recv_if->soft_iface, new_skb, recv_if,
sizeof(struct unicast_packet));
return NET_RX_SUCCESS;
}
return route_unicast_packet(skb, recv_if);
}
int recv_bcast_packet(struct sk_buff *skb, struct hard_iface *recv_if)
{
struct bat_priv *bat_priv = netdev_priv(recv_if->soft_iface);
struct orig_node *orig_node = NULL;
struct bcast_packet *bcast_packet;
struct ethhdr *ethhdr;
int hdr_size = sizeof(struct bcast_packet);
int ret = NET_RX_DROP;
int32_t seq_diff;
/* drop packet if it has not necessary minimum size */
if (unlikely(!pskb_may_pull(skb, hdr_size)))
goto out;
ethhdr = (struct ethhdr *)skb_mac_header(skb);
/* packet with broadcast indication but unicast recipient */
if (!is_broadcast_ether_addr(ethhdr->h_dest))
goto out;
/* packet with broadcast sender address */
if (is_broadcast_ether_addr(ethhdr->h_source))
goto out;
/* ignore broadcasts sent by myself */
if (is_my_mac(ethhdr->h_source))
goto out;
bcast_packet = (struct bcast_packet *)skb->data;
/* ignore broadcasts originated by myself */
if (is_my_mac(bcast_packet->orig))
goto out;
if (bcast_packet->ttl < 2)
goto out;
rcu_read_lock();
orig_node = orig_hash_find(bat_priv, bcast_packet->orig);
if (!orig_node)
goto rcu_unlock;
rcu_read_unlock();
spin_lock_bh(&orig_node->bcast_seqno_lock);
/* check whether the packet is a duplicate */
if (get_bit_status(orig_node->bcast_bits, orig_node->last_bcast_seqno,
ntohl(bcast_packet->seqno)))
goto spin_unlock;
seq_diff = ntohl(bcast_packet->seqno) - orig_node->last_bcast_seqno;
/* check whether the packet is old and the host just restarted. */
if (window_protected(bat_priv, seq_diff,
&orig_node->bcast_seqno_reset))
goto spin_unlock;
/* mark broadcast in flood history, update window position
* if required. */
if (bit_get_packet(bat_priv, orig_node->bcast_bits, seq_diff, 1))
orig_node->last_bcast_seqno = ntohl(bcast_packet->seqno);
spin_unlock_bh(&orig_node->bcast_seqno_lock);
/* rebroadcast packet */
add_bcast_packet_to_list(bat_priv, skb);
/* broadcast for me */
interface_rx(recv_if->soft_iface, skb, recv_if, hdr_size);
ret = NET_RX_SUCCESS;
goto out;
rcu_unlock:
rcu_read_unlock();
goto out;
spin_unlock:
spin_unlock_bh(&orig_node->bcast_seqno_lock);
out:
if (orig_node)
orig_node_free_ref(orig_node);
return ret;
}
int recv_vis_packet(struct sk_buff *skb, struct hard_iface *recv_if)
{
struct vis_packet *vis_packet;
struct ethhdr *ethhdr;
struct bat_priv *bat_priv = netdev_priv(recv_if->soft_iface);
int hdr_size = sizeof(struct vis_packet);
/* keep skb linear */
if (skb_linearize(skb) < 0)
return NET_RX_DROP;
if (unlikely(!pskb_may_pull(skb, hdr_size)))
return NET_RX_DROP;
vis_packet = (struct vis_packet *)skb->data;
ethhdr = (struct ethhdr *)skb_mac_header(skb);
/* not for me */
if (!is_my_mac(ethhdr->h_dest))
return NET_RX_DROP;
/* ignore own packets */
if (is_my_mac(vis_packet->vis_orig))
return NET_RX_DROP;
if (is_my_mac(vis_packet->sender_orig))
return NET_RX_DROP;
switch (vis_packet->vis_type) {
case VIS_TYPE_SERVER_SYNC:
receive_server_sync_packet(bat_priv, vis_packet,
skb_headlen(skb));
break;
case VIS_TYPE_CLIENT_UPDATE:
receive_client_update_packet(bat_priv, vis_packet,
skb_headlen(skb));
break;
default: /* ignore unknown packet */
break;
}
/* We take a copy of the data in the packet, so we should
always free the skbuf. */
return NET_RX_DROP;
}