blob: 066dc8b388177c6fea09d0fb0bd4b8ba91d9e5ab [file] [log] [blame]
/*
* Copyright (C) 2007-2010 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 "device.h"
#include "translation-table.h"
#include "originator.h"
#include "types.h"
#include "ring_buffer.h"
#include "vis.h"
#include "aggregation.h"
DECLARE_WAIT_QUEUE_HEAD(thread_wait);
void slide_own_bcast_window(struct batman_if *batman_if)
{
HASHIT(hashit);
struct orig_node *orig_node;
TYPE_OF_WORD *word;
unsigned long flags;
spin_lock_irqsave(&orig_hash_lock, flags);
while (hash_iterate(orig_hash, &hashit)) {
orig_node = hashit.bucket->data;
word = &(orig_node->bcast_own[batman_if->if_num * NUM_WORDS]);
bit_get_packet(word, 1, 0);
orig_node->bcast_own_sum[batman_if->if_num] =
bit_packet_count(word);
}
spin_unlock_irqrestore(&orig_hash_lock, flags);
}
static void update_HNA(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(orig_node,
"originator changed hna");
if ((hna_buff_len > 0) && (hna_buff != NULL))
hna_global_add_orig(orig_node, hna_buff, hna_buff_len);
}
}
static void update_route(struct orig_node *orig_node,
struct neigh_node *neigh_node,
unsigned char *hna_buff, int hna_buff_len)
{
/* route deleted */
if ((orig_node->router != NULL) && (neigh_node == NULL)) {
bat_dbg(DBG_ROUTES, "Deleting route towards: %pM\n",
orig_node->orig);
hna_global_del_orig(orig_node, "originator timed out");
/* route added */
} else if ((orig_node->router == NULL) && (neigh_node != NULL)) {
bat_dbg(DBG_ROUTES,
"Adding route towards: %pM (via %pM)\n",
orig_node->orig, neigh_node->addr);
hna_global_add_orig(orig_node, hna_buff, hna_buff_len);
/* route changed */
} else {
bat_dbg(DBG_ROUTES,
"Changing route towards: %pM "
"(now via %pM - was via %pM)\n",
orig_node->orig, neigh_node->addr,
orig_node->router->addr);
}
orig_node->router = neigh_node;
}
void update_routes(struct orig_node *orig_node,
struct neigh_node *neigh_node,
unsigned char *hna_buff, int hna_buff_len)
{
if (orig_node == NULL)
return;
if (orig_node->router != neigh_node)
update_route(orig_node, neigh_node, hna_buff, hna_buff_len);
/* may be just HNA changed */
else
update_HNA(orig_node, hna_buff, hna_buff_len);
}
static int isBidirectionalNeigh(struct orig_node *orig_node,
struct orig_node *orig_neigh_node,
struct batman_packet *batman_packet,
struct batman_if *if_incoming)
{
struct neigh_node *neigh_node = NULL, *tmp_neigh_node = NULL;
unsigned char total_count;
if (orig_node == orig_neigh_node) {
list_for_each_entry(tmp_neigh_node,
&orig_node->neigh_list,
list) {
if (compare_orig(tmp_neigh_node->addr,
orig_neigh_node->orig) &&
(tmp_neigh_node->if_incoming == if_incoming))
neigh_node = tmp_neigh_node;
}
if (!neigh_node)
neigh_node = create_neighbor(orig_node,
orig_neigh_node,
orig_neigh_node->orig,
if_incoming);
/* create_neighbor failed, return 0 */
if (!neigh_node)
return 0;
neigh_node->last_valid = jiffies;
} else {
/* find packet count of corresponding one hop neighbor */
list_for_each_entry(tmp_neigh_node,
&orig_neigh_node->neigh_list, list) {
if (compare_orig(tmp_neigh_node->addr,
orig_neigh_node->orig) &&
(tmp_neigh_node->if_incoming == if_incoming))
neigh_node = tmp_neigh_node;
}
if (!neigh_node)
neigh_node = create_neighbor(orig_neigh_node,
orig_neigh_node,
orig_neigh_node->orig,
if_incoming);
/* create_neighbor failed, return 0 */
if (!neigh_node)
return 0;
}
orig_node->last_valid = jiffies;
/* pay attention to not get a value bigger than 100 % */
total_count = (orig_neigh_node->bcast_own_sum[if_incoming->if_num] >
neigh_node->real_packet_count ?
neigh_node->real_packet_count :
orig_neigh_node->bcast_own_sum[if_incoming->if_num]);
/* 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_node->real_packet_count < TQ_LOCAL_BIDRECT_RECV_MINIMUM))
orig_neigh_node->tq_own = 0;
else
/* neigh_node->real_packet_count is never zero as we
* only purge old information when getting new
* information */
orig_neigh_node->tq_own = (TQ_MAX_VALUE * total_count) /
neigh_node->real_packet_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
*/
orig_neigh_node->tq_asym_penalty =
TQ_MAX_VALUE -
(TQ_MAX_VALUE *
(TQ_LOCAL_WINDOW_SIZE - neigh_node->real_packet_count) *
(TQ_LOCAL_WINDOW_SIZE - neigh_node->real_packet_count) *
(TQ_LOCAL_WINDOW_SIZE - neigh_node->real_packet_count)) /
(TQ_LOCAL_WINDOW_SIZE *
TQ_LOCAL_WINDOW_SIZE *
TQ_LOCAL_WINDOW_SIZE);
batman_packet->tq = ((batman_packet->tq *
orig_neigh_node->tq_own *
orig_neigh_node->tq_asym_penalty) /
(TQ_MAX_VALUE * TQ_MAX_VALUE));
bat_dbg(DBG_BATMAN,
"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_node->real_packet_count, orig_neigh_node->tq_own,
orig_neigh_node->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)
return 1;
return 0;
}
static void update_orig(struct orig_node *orig_node, struct ethhdr *ethhdr,
struct batman_packet *batman_packet,
struct batman_if *if_incoming,
unsigned char *hna_buff, int hna_buff_len,
char is_duplicate)
{
struct neigh_node *neigh_node = NULL, *tmp_neigh_node = NULL;
int tmp_hna_buff_len;
bat_dbg(DBG_BATMAN, "update_originator(): "
"Searching and updating originator entry of received packet\n");
list_for_each_entry(tmp_neigh_node, &orig_node->neigh_list, list) {
if (compare_orig(tmp_neigh_node->addr, ethhdr->h_source) &&
(tmp_neigh_node->if_incoming == if_incoming)) {
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(ethhdr->h_source);
if (!orig_tmp)
return;
neigh_node = create_neighbor(orig_node,
orig_tmp,
ethhdr->h_source, if_incoming);
if (!neigh_node)
return;
} else
bat_dbg(DBG_BATMAN,
"Updating existing last-hop neighbor of originator\n");
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;
}
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->router->orig_node->bcast_own_sum[if_incoming->if_num]
>= neigh_node->orig_node->bcast_own_sum[if_incoming->if_num])))
goto update_hna;
update_routes(orig_node, neigh_node, hna_buff, tmp_hna_buff_len);
return;
update_hna:
update_routes(orig_node, orig_node->router, hna_buff, tmp_hna_buff_len);
}
/* 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(int16_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,
"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 batman_if *if_incoming)
{
struct orig_node *orig_node;
struct neigh_node *tmp_neigh_node;
char is_duplicate = 0;
int16_t seq_diff;
int need_update = 0;
int set_mark;
orig_node = get_orig_node(batman_packet->orig);
if (orig_node == NULL)
return 0;
seq_diff = batman_packet->seqno - orig_node->last_real_seqno;
/* signalize caller that the packet is to be dropped. */
if (window_protected(seq_diff, &orig_node->batman_seqno_reset))
return -1;
list_for_each_entry(tmp_neigh_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_orig(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(tmp_neigh_node->real_bits,
seq_diff, set_mark);
tmp_neigh_node->real_packet_count =
bit_packet_count(tmp_neigh_node->real_bits);
}
if (need_update) {
bat_dbg(DBG_BATMAN, "updating last_seqno: old %d, new %d\n",
orig_node->last_real_seqno, batman_packet->seqno);
orig_node->last_real_seqno = batman_packet->seqno;
}
return is_duplicate;
}
void receive_bat_packet(struct ethhdr *ethhdr,
struct batman_packet *batman_packet,
unsigned char *hna_buff, int hna_buff_len,
struct batman_if *if_incoming)
{
struct batman_if *batman_if;
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;
unsigned short 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_orig(ethhdr->h_source,
batman_packet->orig) ? 1 : 0);
bat_dbg(DBG_BATMAN, "Received BATMAN packet via NB: %pM, IF: %s [%s] "
"(from OG: %pM, via prev OG: %pM, seqno %d, tq %d, "
"TTL %d, V %d, IDF %d)\n",
ethhdr->h_source, if_incoming->dev, if_incoming->addr_str,
batman_packet->orig, batman_packet->prev_sender,
batman_packet->seqno, batman_packet->tq, batman_packet->ttl,
batman_packet->version, has_directlink_flag);
list_for_each_entry_rcu(batman_if, &if_list, list) {
if (batman_if->if_status != IF_ACTIVE)
continue;
if (compare_orig(ethhdr->h_source,
batman_if->net_dev->dev_addr))
is_my_addr = 1;
if (compare_orig(batman_packet->orig,
batman_if->net_dev->dev_addr))
is_my_orig = 1;
if (compare_orig(batman_packet->prev_sender,
batman_if->net_dev->dev_addr))
is_my_oldorig = 1;
if (compare_orig(ethhdr->h_source, broadcastAddr))
is_broadcast = 1;
}
if (batman_packet->version != COMPAT_VERSION) {
bat_dbg(DBG_BATMAN,
"Drop packet: incompatible batman version (%i)\n",
batman_packet->version);
return;
}
if (is_my_addr) {
bat_dbg(DBG_BATMAN,
"Drop packet: received my own broadcast (sender: %pM"
")\n",
ethhdr->h_source);
return;
}
if (is_broadcast) {
bat_dbg(DBG_BATMAN, "Drop packet: "
"ignoring all packets with broadcast source addr (sender: %pM"
")\n", ethhdr->h_source);
return;
}
if (is_my_orig) {
TYPE_OF_WORD *word;
int offset;
orig_neigh_node = get_orig_node(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_orig(if_incoming->net_dev->dev_addr,
batman_packet->orig) &&
(batman_packet->seqno - if_incoming_seqno + 2 == 0)) {
offset = if_incoming->if_num * NUM_WORDS;
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);
}
bat_dbg(DBG_BATMAN, "Drop packet: "
"originator packet from myself (via neighbor)\n");
return;
}
if (is_my_oldorig) {
bat_dbg(DBG_BATMAN,
"Drop packet: ignoring all rebroadcast echos (sender: "
"%pM)\n", ethhdr->h_source);
return;
}
orig_node = get_orig_node(batman_packet->orig);
if (orig_node == NULL)
return;
is_duplicate = count_real_packets(ethhdr, batman_packet, if_incoming);
if (is_duplicate == -1) {
bat_dbg(DBG_BATMAN,
"Drop packet: packet within seqno protection time "
"(sender: %pM)\n", ethhdr->h_source);
return;
}
if (batman_packet->tq == 0) {
bat_dbg(DBG_BATMAN,
"Drop packet: originator packet with tq equal 0\n");
return;
}
/* avoid temporary routing loops */
if ((orig_node->router) &&
(orig_node->router->orig_node->router) &&
(compare_orig(orig_node->router->addr,
batman_packet->prev_sender)) &&
!(compare_orig(batman_packet->orig, batman_packet->prev_sender)) &&
(compare_orig(orig_node->router->addr,
orig_node->router->orig_node->router->addr))) {
bat_dbg(DBG_BATMAN,
"Drop packet: ignoring all rebroadcast packets that "
"may make me loop (sender: %pM)\n", ethhdr->h_source);
return;
}
/* if sender is a direct neighbor the sender mac equals
* originator mac */
orig_neigh_node = (is_single_hop_neigh ?
orig_node : get_orig_node(ethhdr->h_source));
if (orig_neigh_node == NULL)
return;
/* 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 == NULL)) {
bat_dbg(DBG_BATMAN, "Drop packet: OGM via unknown neighbor!\n");
return;
}
is_bidirectional = isBidirectionalNeigh(orig_node, orig_neigh_node,
batman_packet, if_incoming);
/* 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(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, "Forwarding packet: "
"rebroadcast neighbor packet with direct link flag\n");
return;
}
/* multihop originator */
if (!is_bidirectional) {
bat_dbg(DBG_BATMAN,
"Drop packet: not received via bidirectional link\n");
return;
}
if (is_duplicate) {
bat_dbg(DBG_BATMAN, "Drop packet: duplicate packet received\n");
return;
}
bat_dbg(DBG_BATMAN,
"Forwarding packet: rebroadcast originator packet\n");
schedule_forward_packet(orig_node, ethhdr, batman_packet,
0, hna_buff_len, if_incoming);
}
int recv_bat_packet(struct sk_buff *skb,
struct batman_if *batman_if)
{
struct ethhdr *ethhdr;
unsigned long flags;
struct sk_buff *skb_old;
/* drop packet if it has not necessary minimum size */
if (skb_headlen(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_bcast(ethhdr->h_dest))
return NET_RX_DROP;
/* packet with broadcast sender address */
if (is_bcast(ethhdr->h_source))
return NET_RX_DROP;
/* TODO: we use headlen instead of "length", because
* only this data is paged in. */
/* create a copy of the skb, if needed, to modify it. */
if (!skb_clone_writable(skb, skb_headlen(skb))) {
skb_old = skb;
skb = skb_copy(skb, GFP_ATOMIC);
if (!skb)
return NET_RX_DROP;
ethhdr = (struct ethhdr *)skb_mac_header(skb);
kfree_skb(skb_old);
}
spin_lock_irqsave(&orig_hash_lock, flags);
receive_aggr_bat_packet(ethhdr,
skb->data,
skb_headlen(skb),
batman_if);
spin_unlock_irqrestore(&orig_hash_lock, flags);
kfree_skb(skb);
return NET_RX_SUCCESS;
}
static int recv_my_icmp_packet(struct sk_buff *skb)
{
struct orig_node *orig_node;
struct icmp_packet *icmp_packet;
struct ethhdr *ethhdr;
struct sk_buff *skb_old;
struct batman_if *batman_if;
int ret;
unsigned long flags;
uint8_t dstaddr[ETH_ALEN];
icmp_packet = (struct icmp_packet *)skb->data;
ethhdr = (struct ethhdr *)skb_mac_header(skb);
/* add data to device queue */
if (icmp_packet->msg_type != ECHO_REQUEST) {
bat_device_receive_packet(icmp_packet);
return NET_RX_DROP;
}
/* answer echo request (ping) */
/* get routing information */
spin_lock_irqsave(&orig_hash_lock, flags);
orig_node = ((struct orig_node *)hash_find(orig_hash,
icmp_packet->orig));
ret = NET_RX_DROP;
if ((orig_node != NULL) &&
(orig_node->router != NULL)) {
/* don't lock while sending the packets ... we therefore
* copy the required data before sending */
batman_if = orig_node->router->if_incoming;
memcpy(dstaddr, orig_node->router->addr, ETH_ALEN);
spin_unlock_irqrestore(&orig_hash_lock, flags);
/* create a copy of the skb, if needed, to modify it. */
skb_old = NULL;
if (!skb_clone_writable(skb, sizeof(struct icmp_packet))) {
skb_old = skb;
skb = skb_copy(skb, GFP_ATOMIC);
if (!skb)
return NET_RX_DROP;
icmp_packet = (struct icmp_packet *)skb->data;
ethhdr = (struct ethhdr *)skb_mac_header(skb);
kfree_skb(skb_old);
}
memcpy(icmp_packet->dst, icmp_packet->orig, ETH_ALEN);
memcpy(icmp_packet->orig, ethhdr->h_dest, ETH_ALEN);
icmp_packet->msg_type = ECHO_REPLY;
icmp_packet->ttl = TTL;
send_skb_packet(skb, batman_if, dstaddr);
ret = NET_RX_SUCCESS;
} else
spin_unlock_irqrestore(&orig_hash_lock, flags);
return ret;
}
static int recv_icmp_ttl_exceeded(struct sk_buff *skb)
{
struct orig_node *orig_node;
struct icmp_packet *icmp_packet;
struct ethhdr *ethhdr;
struct sk_buff *skb_old;
struct batman_if *batman_if;
int ret;
unsigned long flags;
uint8_t dstaddr[ETH_ALEN];
icmp_packet = (struct icmp_packet *)skb->data;
ethhdr = (struct ethhdr *)skb_mac_header(skb);
/* send TTL exceeded if packet is an echo request (traceroute) */
if (icmp_packet->msg_type != ECHO_REQUEST) {
printk(KERN_WARNING "batman-adv:"
"Warning - can't forward icmp packet from %pM to %pM: "
"ttl exceeded\n",
icmp_packet->orig, icmp_packet->dst);
return NET_RX_DROP;
}
/* get routing information */
spin_lock_irqsave(&orig_hash_lock, flags);
orig_node = ((struct orig_node *)
hash_find(orig_hash, icmp_packet->orig));
ret = NET_RX_DROP;
if ((orig_node != NULL) &&
(orig_node->router != NULL)) {
/* don't lock while sending the packets ... we therefore
* copy the required data before sending */
batman_if = orig_node->router->if_incoming;
memcpy(dstaddr, orig_node->router->addr, ETH_ALEN);
spin_unlock_irqrestore(&orig_hash_lock, flags);
/* create a copy of the skb, if needed, to modify it. */
if (!skb_clone_writable(skb, sizeof(struct icmp_packet))) {
skb_old = skb;
skb = skb_copy(skb, GFP_ATOMIC);
if (!skb)
return NET_RX_DROP;
icmp_packet = (struct icmp_packet *) skb->data;
ethhdr = (struct ethhdr *)skb_mac_header(skb);
kfree_skb(skb_old);
}
memcpy(icmp_packet->dst, icmp_packet->orig, ETH_ALEN);
memcpy(icmp_packet->orig, ethhdr->h_dest, ETH_ALEN);
icmp_packet->msg_type = TTL_EXCEEDED;
icmp_packet->ttl = TTL;
send_skb_packet(skb, batman_if, dstaddr);
ret = NET_RX_SUCCESS;
} else
spin_unlock_irqrestore(&orig_hash_lock, flags);
return ret;
}
int recv_icmp_packet(struct sk_buff *skb)
{
struct icmp_packet *icmp_packet;
struct ethhdr *ethhdr;
struct orig_node *orig_node;
struct sk_buff *skb_old;
struct batman_if *batman_if;
int hdr_size = sizeof(struct icmp_packet);
int ret;
unsigned long flags;
uint8_t dstaddr[ETH_ALEN];
/* drop packet if it has not necessary minimum size */
if (skb_headlen(skb) < hdr_size)
return NET_RX_DROP;
ethhdr = (struct ethhdr *)skb_mac_header(skb);
/* packet with unicast indication but broadcast recipient */
if (is_bcast(ethhdr->h_dest))
return NET_RX_DROP;
/* packet with broadcast sender address */
if (is_bcast(ethhdr->h_source))
return NET_RX_DROP;
/* not for me */
if (!is_my_mac(ethhdr->h_dest))
return NET_RX_DROP;
icmp_packet = (struct icmp_packet *)skb->data;
/* packet for me */
if (is_my_mac(icmp_packet->dst))
return recv_my_icmp_packet(skb);
/* TTL exceeded */
if (icmp_packet->ttl < 2)
return recv_icmp_ttl_exceeded(skb);
ret = NET_RX_DROP;
/* get routing information */
spin_lock_irqsave(&orig_hash_lock, flags);
orig_node = ((struct orig_node *)
hash_find(orig_hash, icmp_packet->dst));
if ((orig_node != NULL) &&
(orig_node->router != NULL)) {
/* don't lock while sending the packets ... we therefore
* copy the required data before sending */
batman_if = orig_node->router->if_incoming;
memcpy(dstaddr, orig_node->router->addr, ETH_ALEN);
spin_unlock_irqrestore(&orig_hash_lock, flags);
/* create a copy of the skb, if needed, to modify it. */
if (!skb_clone_writable(skb, sizeof(struct icmp_packet))) {
skb_old = skb;
skb = skb_copy(skb, GFP_ATOMIC);
if (!skb)
return NET_RX_DROP;
icmp_packet = (struct icmp_packet *)skb->data;
ethhdr = (struct ethhdr *)skb_mac_header(skb);
kfree_skb(skb_old);
}
/* decrement ttl */
icmp_packet->ttl--;
/* route it */
send_skb_packet(skb, batman_if, dstaddr);
ret = NET_RX_SUCCESS;
} else
spin_unlock_irqrestore(&orig_hash_lock, flags);
return ret;
}
int recv_unicast_packet(struct sk_buff *skb)
{
struct unicast_packet *unicast_packet;
struct orig_node *orig_node;
struct ethhdr *ethhdr;
struct batman_if *batman_if;
struct sk_buff *skb_old;
uint8_t dstaddr[ETH_ALEN];
int hdr_size = sizeof(struct unicast_packet);
int ret;
unsigned long flags;
/* drop packet if it has not necessary minimum size */
if (skb_headlen(skb) < hdr_size)
return NET_RX_DROP;
ethhdr = (struct ethhdr *) skb_mac_header(skb);
/* packet with unicast indication but broadcast recipient */
if (is_bcast(ethhdr->h_dest))
return NET_RX_DROP;
/* packet with broadcast sender address */
if (is_bcast(ethhdr->h_source))
return NET_RX_DROP;
/* not for me */
if (!is_my_mac(ethhdr->h_dest))
return NET_RX_DROP;
unicast_packet = (struct unicast_packet *) skb->data;
/* packet for me */
if (is_my_mac(unicast_packet->dest)) {
interface_rx(skb, hdr_size);
return NET_RX_SUCCESS;
}
/* TTL exceeded */
if (unicast_packet->ttl < 2) {
printk(KERN_WARNING "batman-adv:Warning - "
"can't forward unicast packet from %pM to %pM: "
"ttl exceeded\n",
ethhdr->h_source, unicast_packet->dest);
return NET_RX_DROP;
}
ret = NET_RX_DROP;
/* get routing information */
spin_lock_irqsave(&orig_hash_lock, flags);
orig_node = ((struct orig_node *)
hash_find(orig_hash, unicast_packet->dest));
if ((orig_node != NULL) &&
(orig_node->router != NULL)) {
/* don't lock while sending the packets ... we therefore
* copy the required data before sending */
batman_if = orig_node->router->if_incoming;
memcpy(dstaddr, orig_node->router->addr, ETH_ALEN);
spin_unlock_irqrestore(&orig_hash_lock, flags);
/* create a copy of the skb, if needed, to modify it. */
if (!skb_clone_writable(skb, sizeof(struct unicast_packet))) {
skb_old = skb;
skb = skb_copy(skb, GFP_ATOMIC);
if (!skb)
return NET_RX_DROP;
unicast_packet = (struct unicast_packet *)skb->data;
ethhdr = (struct ethhdr *)skb_mac_header(skb);
kfree_skb(skb_old);
}
/* decrement ttl */
unicast_packet->ttl--;
/* route it */
send_skb_packet(skb, batman_if, dstaddr);
ret = NET_RX_SUCCESS;
} else
spin_unlock_irqrestore(&orig_hash_lock, flags);
return ret;
}
int recv_bcast_packet(struct sk_buff *skb)
{
struct orig_node *orig_node;
struct bcast_packet *bcast_packet;
struct ethhdr *ethhdr;
int hdr_size = sizeof(struct bcast_packet);
int16_t seq_diff;
unsigned long flags;
/* drop packet if it has not necessary minimum size */
if (skb_headlen(skb) < hdr_size)
return NET_RX_DROP;
ethhdr = (struct ethhdr *)skb_mac_header(skb);
/* packet with broadcast indication but unicast recipient */
if (!is_bcast(ethhdr->h_dest))
return NET_RX_DROP;
/* packet with broadcast sender address */
if (is_bcast(ethhdr->h_source))
return NET_RX_DROP;
/* ignore broadcasts sent by myself */
if (is_my_mac(ethhdr->h_source))
return NET_RX_DROP;
bcast_packet = (struct bcast_packet *)skb->data;
/* ignore broadcasts originated by myself */
if (is_my_mac(bcast_packet->orig))
return NET_RX_DROP;
spin_lock_irqsave(&orig_hash_lock, flags);
orig_node = ((struct orig_node *)
hash_find(orig_hash, bcast_packet->orig));
if (orig_node == NULL) {
spin_unlock_irqrestore(&orig_hash_lock, flags);
return NET_RX_DROP;
}
/* check whether the packet is a duplicate */
if (get_bit_status(orig_node->bcast_bits,
orig_node->last_bcast_seqno,
ntohs(bcast_packet->seqno))) {
spin_unlock_irqrestore(&orig_hash_lock, flags);
return NET_RX_DROP;
}
seq_diff = ntohs(bcast_packet->seqno) - orig_node->last_bcast_seqno;
/* check whether the packet is old and the host just restarted. */
if (window_protected(seq_diff, &orig_node->bcast_seqno_reset)) {
spin_unlock_irqrestore(&orig_hash_lock, flags);
return NET_RX_DROP;
}
/* mark broadcast in flood history, update window position
* if required. */
if (bit_get_packet(orig_node->bcast_bits, seq_diff, 1))
orig_node->last_bcast_seqno = ntohs(bcast_packet->seqno);
spin_unlock_irqrestore(&orig_hash_lock, flags);
/* rebroadcast packet */
add_bcast_packet_to_list(skb);
/* broadcast for me */
interface_rx(skb, hdr_size);
return NET_RX_SUCCESS;
}
int recv_vis_packet(struct sk_buff *skb)
{
struct vis_packet *vis_packet;
struct ethhdr *ethhdr;
struct bat_priv *bat_priv;
int hdr_size = sizeof(struct vis_packet);
if (skb_headlen(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;
/* FIXME: each batman_if will be attached to a softif */
bat_priv = netdev_priv(soft_device);
switch (vis_packet->vis_type) {
case VIS_TYPE_SERVER_SYNC:
/* TODO: handle fragmented skbs properly */
receive_server_sync_packet(bat_priv, vis_packet,
skb_headlen(skb));
break;
case VIS_TYPE_CLIENT_UPDATE:
/* TODO: handle fragmented skbs properly */
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;
}