blob: 1d3d954847fdaa4dc18c7fce12ea6d27ba23e2e0 [file] [log] [blame]
/*
* Copyright (C) 2008-2010 B.A.T.M.A.N. contributors:
*
* 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 "send.h"
#include "translation-table.h"
#include "vis.h"
#include "soft-interface.h"
#include "hard-interface.h"
#include "hash.h"
/* Returns the smallest signed integer in two's complement with the sizeof x */
#define smallest_signed_int(x) (1u << (7u + 8u * (sizeof(x) - 1u)))
/* Checks if a sequence number x is a predecessor/successor of y.
they handle overflows/underflows and can correctly check for a
predecessor/successor unless the variable sequence number has grown by
more then 2**(bitwidth(x)-1)-1.
This means that for a uint8_t with the maximum value 255, it would think:
* when adding nothing - it is neither a predecessor nor a successor
* before adding more than 127 to the starting value - it is a predecessor,
* when adding 128 - it is neither a predecessor nor a successor,
* after adding more than 127 to the starting value - it is a successor */
#define seq_before(x, y) ({typeof(x) _dummy = (x - y); \
_dummy > smallest_signed_int(_dummy); })
#define seq_after(x, y) seq_before(y, x)
struct hashtable_t *vis_hash;
DEFINE_SPINLOCK(vis_hash_lock);
static DEFINE_SPINLOCK(recv_list_lock);
static struct vis_info *my_vis_info;
static struct list_head send_list; /* always locked with vis_hash_lock */
static void start_vis_timer(void);
/* free the info */
static void free_info(struct kref *ref)
{
struct vis_info *info = container_of(ref, struct vis_info, refcount);
struct recvlist_node *entry, *tmp;
unsigned long flags;
list_del_init(&info->send_list);
spin_lock_irqsave(&recv_list_lock, flags);
list_for_each_entry_safe(entry, tmp, &info->recv_list, list) {
list_del(&entry->list);
kfree(entry);
}
spin_unlock_irqrestore(&recv_list_lock, flags);
kfree(info);
}
/* Compare two vis packets, used by the hashing algorithm */
static int vis_info_cmp(void *data1, void *data2)
{
struct vis_info *d1, *d2;
d1 = data1;
d2 = data2;
return compare_orig(d1->packet.vis_orig, d2->packet.vis_orig);
}
/* hash function to choose an entry in a hash table of given size */
/* hash algorithm from http://en.wikipedia.org/wiki/Hash_table */
static int vis_info_choose(void *data, int size)
{
struct vis_info *vis_info = data;
unsigned char *key;
uint32_t hash = 0;
size_t i;
key = vis_info->packet.vis_orig;
for (i = 0; i < ETH_ALEN; i++) {
hash += key[i];
hash += (hash << 10);
hash ^= (hash >> 6);
}
hash += (hash << 3);
hash ^= (hash >> 11);
hash += (hash << 15);
return hash % size;
}
/* insert interface to the list of interfaces of one originator, if it
* does not already exist in the list */
static void vis_data_insert_interface(const uint8_t *interface,
struct hlist_head *if_list,
bool primary)
{
struct if_list_entry *entry;
struct hlist_node *pos;
hlist_for_each_entry(entry, pos, if_list, list) {
if (compare_orig(entry->addr, (void *)interface))
return;
}
/* its a new address, add it to the list */
entry = kmalloc(sizeof(*entry), GFP_KERNEL);
if (!entry)
return;
memcpy(entry->addr, interface, ETH_ALEN);
entry->primary = primary;
hlist_add_head(&entry->list, if_list);
}
static ssize_t vis_data_read_prim_sec(char *buff, struct hlist_head *if_list)
{
struct if_list_entry *entry;
struct hlist_node *pos;
char tmp_addr_str[ETH_STR_LEN];
size_t len = 0;
hlist_for_each_entry(entry, pos, if_list, list) {
if (entry->primary)
len += sprintf(buff + len, "PRIMARY, ");
else {
addr_to_string(tmp_addr_str, entry->addr);
len += sprintf(buff + len, "SEC %s, ", tmp_addr_str);
}
}
return len;
}
/* read an entry */
static ssize_t vis_data_read_entry(char *buff, struct vis_info_entry *entry,
uint8_t *src, bool primary)
{
char to[40];
addr_to_string(to, entry->dest);
if (primary && entry->quality == 0)
return sprintf(buff, "HNA %s, ", to);
else if (compare_orig(entry->src, src))
return sprintf(buff, "TQ %s %d, ", to, entry->quality);
return 0;
}
ssize_t vis_fill_buffer_text(struct net_device *net_dev, char *buff,
size_t count, loff_t off)
{
HASHIT(hashit);
struct vis_info *info;
struct vis_info_entry *entries;
struct bat_priv *bat_priv = netdev_priv(net_dev);
HLIST_HEAD(vis_if_list);
struct if_list_entry *entry;
struct hlist_node *pos, *n;
size_t hdr_len, tmp_len;
int i, bytes_written = 0;
char tmp_addr_str[ETH_STR_LEN];
unsigned long flags;
int vis_server = atomic_read(&bat_priv->vis_mode);
if ((!bat_priv->primary_if) ||
(vis_server == VIS_TYPE_CLIENT_UPDATE))
return 0;
hdr_len = 0;
spin_lock_irqsave(&vis_hash_lock, flags);
while (hash_iterate(vis_hash, &hashit)) {
info = hashit.bucket->data;
entries = (struct vis_info_entry *)
((char *)info + sizeof(struct vis_info));
/* estimated line length */
if (count < bytes_written + 200)
break;
for (i = 0; i < info->packet.entries; i++) {
if (entries[i].quality == 0)
continue;
vis_data_insert_interface(entries[i].src, &vis_if_list,
compare_orig(entries[i].src,
info->packet.vis_orig));
}
hlist_for_each_entry(entry, pos, &vis_if_list, list) {
addr_to_string(tmp_addr_str, entry->addr);
tmp_len = sprintf(buff + bytes_written,
"%s,", tmp_addr_str);
for (i = 0; i < info->packet.entries; i++)
tmp_len += vis_data_read_entry(
buff + bytes_written + tmp_len,
&entries[i], entry->addr,
entry->primary);
/* add primary/secondary records */
if (compare_orig(entry->addr, info->packet.vis_orig))
tmp_len += vis_data_read_prim_sec(
buff + bytes_written + tmp_len,
&vis_if_list);
tmp_len += sprintf(buff + bytes_written + tmp_len,
"\n");
hdr_len += tmp_len;
if (off >= hdr_len)
continue;
bytes_written += tmp_len;
}
hlist_for_each_entry_safe(entry, pos, n, &vis_if_list, list) {
hlist_del(&entry->list);
kfree(entry);
}
}
spin_unlock_irqrestore(&vis_hash_lock, flags);
return bytes_written;
}
/* add the info packet to the send list, if it was not
* already linked in. */
static void send_list_add(struct vis_info *info)
{
if (list_empty(&info->send_list)) {
kref_get(&info->refcount);
list_add_tail(&info->send_list, &send_list);
}
}
/* delete the info packet from the send list, if it was
* linked in. */
static void send_list_del(struct vis_info *info)
{
if (!list_empty(&info->send_list)) {
list_del_init(&info->send_list);
kref_put(&info->refcount, free_info);
}
}
/* tries to add one entry to the receive list. */
static void recv_list_add(struct list_head *recv_list, char *mac)
{
struct recvlist_node *entry;
unsigned long flags;
entry = kmalloc(sizeof(struct recvlist_node), GFP_ATOMIC);
if (!entry)
return;
memcpy(entry->mac, mac, ETH_ALEN);
spin_lock_irqsave(&recv_list_lock, flags);
list_add_tail(&entry->list, recv_list);
spin_unlock_irqrestore(&recv_list_lock, flags);
}
/* returns 1 if this mac is in the recv_list */
static int recv_list_is_in(struct list_head *recv_list, char *mac)
{
struct recvlist_node *entry;
unsigned long flags;
spin_lock_irqsave(&recv_list_lock, flags);
list_for_each_entry(entry, recv_list, list) {
if (memcmp(entry->mac, mac, ETH_ALEN) == 0) {
spin_unlock_irqrestore(&recv_list_lock, flags);
return 1;
}
}
spin_unlock_irqrestore(&recv_list_lock, flags);
return 0;
}
/* try to add the packet to the vis_hash. return NULL if invalid (e.g. too old,
* broken.. ). vis hash must be locked outside. is_new is set when the packet
* is newer than old entries in the hash. */
static struct vis_info *add_packet(struct vis_packet *vis_packet,
int vis_info_len, int *is_new,
int make_broadcast)
{
struct vis_info *info, *old_info;
struct vis_info search_elem;
*is_new = 0;
/* sanity check */
if (vis_hash == NULL)
return NULL;
/* see if the packet is already in vis_hash */
memcpy(search_elem.packet.vis_orig, vis_packet->vis_orig, ETH_ALEN);
old_info = hash_find(vis_hash, &search_elem);
if (old_info != NULL) {
if (!seq_after(vis_packet->seqno, old_info->packet.seqno)) {
if (old_info->packet.seqno == vis_packet->seqno) {
recv_list_add(&old_info->recv_list,
vis_packet->sender_orig);
return old_info;
} else {
/* newer packet is already in hash. */
return NULL;
}
}
/* remove old entry */
hash_remove(vis_hash, old_info);
send_list_del(old_info);
kref_put(&old_info->refcount, free_info);
}
info = kmalloc(sizeof(struct vis_info) + vis_info_len, GFP_ATOMIC);
if (info == NULL)
return NULL;
kref_init(&info->refcount);
INIT_LIST_HEAD(&info->send_list);
INIT_LIST_HEAD(&info->recv_list);
info->first_seen = jiffies;
memcpy(&info->packet, vis_packet,
sizeof(struct vis_packet) + vis_info_len);
/* initialize and add new packet. */
*is_new = 1;
/* Make it a broadcast packet, if required */
if (make_broadcast)
memcpy(info->packet.target_orig, broadcastAddr, ETH_ALEN);
/* repair if entries is longer than packet. */
if (info->packet.entries * sizeof(struct vis_info_entry) > vis_info_len)
info->packet.entries = vis_info_len /
sizeof(struct vis_info_entry);
recv_list_add(&info->recv_list, info->packet.sender_orig);
/* try to add it */
if (hash_add(vis_hash, info) < 0) {
/* did not work (for some reason) */
kref_put(&old_info->refcount, free_info);
info = NULL;
}
return info;
}
/* handle the server sync packet, forward if needed. */
void receive_server_sync_packet(struct bat_priv *bat_priv,
struct vis_packet *vis_packet,
int vis_info_len)
{
struct vis_info *info;
int is_new, make_broadcast;
unsigned long flags;
int vis_server = atomic_read(&bat_priv->vis_mode);
make_broadcast = (vis_server == VIS_TYPE_SERVER_SYNC);
spin_lock_irqsave(&vis_hash_lock, flags);
info = add_packet(vis_packet, vis_info_len, &is_new, make_broadcast);
if (info == NULL)
goto end;
/* only if we are server ourselves and packet is newer than the one in
* hash.*/
if (vis_server == VIS_TYPE_SERVER_SYNC && is_new)
send_list_add(info);
end:
spin_unlock_irqrestore(&vis_hash_lock, flags);
}
/* handle an incoming client update packet and schedule forward if needed. */
void receive_client_update_packet(struct bat_priv *bat_priv,
struct vis_packet *vis_packet,
int vis_info_len)
{
struct vis_info *info;
int is_new;
unsigned long flags;
int vis_server = atomic_read(&bat_priv->vis_mode);
int are_target = 0;
/* clients shall not broadcast. */
if (is_bcast(vis_packet->target_orig))
return;
/* Are we the target for this VIS packet? */
if (vis_server == VIS_TYPE_SERVER_SYNC &&
is_my_mac(vis_packet->target_orig))
are_target = 1;
spin_lock_irqsave(&vis_hash_lock, flags);
info = add_packet(vis_packet, vis_info_len, &is_new, are_target);
if (info == NULL)
goto end;
/* note that outdated packets will be dropped at this point. */
/* send only if we're the target server or ... */
if (are_target && is_new) {
info->packet.vis_type = VIS_TYPE_SERVER_SYNC; /* upgrade! */
send_list_add(info);
/* ... we're not the recipient (and thus need to forward). */
} else if (!is_my_mac(info->packet.target_orig)) {
send_list_add(info);
}
end:
spin_unlock_irqrestore(&vis_hash_lock, flags);
}
/* Walk the originators and find the VIS server with the best tq. Set the packet
* address to its address and return the best_tq.
*
* Must be called with the originator hash locked */
static int find_best_vis_server(struct vis_info *info)
{
HASHIT(hashit);
struct orig_node *orig_node;
int best_tq = -1;
while (hash_iterate(orig_hash, &hashit)) {
orig_node = hashit.bucket->data;
if ((orig_node != NULL) &&
(orig_node->router != NULL) &&
(orig_node->flags & VIS_SERVER) &&
(orig_node->router->tq_avg > best_tq)) {
best_tq = orig_node->router->tq_avg;
memcpy(info->packet.target_orig, orig_node->orig,
ETH_ALEN);
}
}
return best_tq;
}
/* Return true if the vis packet is full. */
static bool vis_packet_full(struct vis_info *info)
{
if (info->packet.entries + 1 >
(1000 - sizeof(struct vis_info)) / sizeof(struct vis_info_entry))
return true;
return false;
}
/* generates a packet of own vis data,
* returns 0 on success, -1 if no packet could be generated */
static int generate_vis_packet(struct bat_priv *bat_priv)
{
HASHIT(hashit_local);
HASHIT(hashit_global);
struct orig_node *orig_node;
struct vis_info *info = (struct vis_info *)my_vis_info;
struct vis_info_entry *entry, *entry_array;
struct hna_local_entry *hna_local_entry;
int best_tq = -1;
unsigned long flags;
info->first_seen = jiffies;
info->packet.vis_type = atomic_read(&bat_priv->vis_mode);
spin_lock_irqsave(&orig_hash_lock, flags);
memcpy(info->packet.target_orig, broadcastAddr, ETH_ALEN);
info->packet.ttl = TTL;
info->packet.seqno++;
info->packet.entries = 0;
if (info->packet.vis_type == VIS_TYPE_CLIENT_UPDATE) {
best_tq = find_best_vis_server(info);
if (best_tq < 0) {
spin_unlock_irqrestore(&orig_hash_lock, flags);
return -1;
}
}
entry_array = (struct vis_info_entry *)
((char *)info + sizeof(struct vis_info));
while (hash_iterate(orig_hash, &hashit_global)) {
orig_node = hashit_global.bucket->data;
if (orig_node->router != NULL
&& compare_orig(orig_node->router->addr,
orig_node->orig)
&& (orig_node->router->if_incoming->if_status ==
IF_ACTIVE)
&& orig_node->router->tq_avg > 0) {
/* fill one entry into buffer. */
entry = &entry_array[info->packet.entries];
memcpy(entry->src,
orig_node->router->if_incoming->net_dev->dev_addr,
ETH_ALEN);
memcpy(entry->dest, orig_node->orig, ETH_ALEN);
entry->quality = orig_node->router->tq_avg;
info->packet.entries++;
if (vis_packet_full(info)) {
spin_unlock_irqrestore(&orig_hash_lock, flags);
return 0;
}
}
}
spin_unlock_irqrestore(&orig_hash_lock, flags);
spin_lock_irqsave(&hna_local_hash_lock, flags);
while (hash_iterate(hna_local_hash, &hashit_local)) {
hna_local_entry = hashit_local.bucket->data;
entry = &entry_array[info->packet.entries];
memset(entry->src, 0, ETH_ALEN);
memcpy(entry->dest, hna_local_entry->addr, ETH_ALEN);
entry->quality = 0; /* 0 means HNA */
info->packet.entries++;
if (vis_packet_full(info)) {
spin_unlock_irqrestore(&hna_local_hash_lock, flags);
return 0;
}
}
spin_unlock_irqrestore(&hna_local_hash_lock, flags);
return 0;
}
/* free old vis packets. Must be called with this vis_hash_lock
* held */
static void purge_vis_packets(void)
{
HASHIT(hashit);
struct vis_info *info;
while (hash_iterate(vis_hash, &hashit)) {
info = hashit.bucket->data;
if (info == my_vis_info) /* never purge own data. */
continue;
if (time_after(jiffies,
info->first_seen + (VIS_TIMEOUT*HZ)/1000)) {
hash_remove_bucket(vis_hash, &hashit);
send_list_del(info);
kref_put(&info->refcount, free_info);
}
}
}
static void broadcast_vis_packet(struct vis_info *info, int packet_length)
{
HASHIT(hashit);
struct orig_node *orig_node;
unsigned long flags;
struct batman_if *batman_if;
uint8_t dstaddr[ETH_ALEN];
spin_lock_irqsave(&orig_hash_lock, flags);
/* send to all routers in range. */
while (hash_iterate(orig_hash, &hashit)) {
orig_node = hashit.bucket->data;
/* if it's a vis server and reachable, send it. */
if ((!orig_node) || (!orig_node->router))
continue;
if (!(orig_node->flags & VIS_SERVER))
continue;
/* don't send it if we already received the packet from
* this node. */
if (recv_list_is_in(&info->recv_list, orig_node->orig))
continue;
memcpy(info->packet.target_orig, orig_node->orig, ETH_ALEN);
batman_if = orig_node->router->if_incoming;
memcpy(dstaddr, orig_node->router->addr, ETH_ALEN);
spin_unlock_irqrestore(&orig_hash_lock, flags);
send_raw_packet((unsigned char *)&info->packet,
packet_length, batman_if, dstaddr);
spin_lock_irqsave(&orig_hash_lock, flags);
}
spin_unlock_irqrestore(&orig_hash_lock, flags);
memcpy(info->packet.target_orig, broadcastAddr, ETH_ALEN);
}
static void unicast_vis_packet(struct vis_info *info, int packet_length)
{
struct orig_node *orig_node;
unsigned long flags;
struct batman_if *batman_if;
uint8_t dstaddr[ETH_ALEN];
spin_lock_irqsave(&orig_hash_lock, flags);
orig_node = ((struct orig_node *)
hash_find(orig_hash, info->packet.target_orig));
if ((!orig_node) || (!orig_node->router))
goto out;
/* 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);
send_raw_packet((unsigned char *)&info->packet,
packet_length, batman_if, dstaddr);
return;
out:
spin_unlock_irqrestore(&orig_hash_lock, flags);
}
/* only send one vis packet. called from send_vis_packets() */
static void send_vis_packet(struct vis_info *info)
{
int packet_length;
if (info->packet.ttl < 2) {
printk(KERN_WARNING "batman-adv: Error - can't send vis packet: ttl exceeded\n");
return;
}
memcpy(info->packet.sender_orig, mainIfAddr, ETH_ALEN);
info->packet.ttl--;
packet_length = sizeof(struct vis_packet) +
info->packet.entries * sizeof(struct vis_info_entry);
if (is_bcast(info->packet.target_orig))
broadcast_vis_packet(info, packet_length);
else
unicast_vis_packet(info, packet_length);
info->packet.ttl++; /* restore TTL */
}
/* called from timer; send (and maybe generate) vis packet. */
static void send_vis_packets(struct work_struct *work)
{
struct vis_info *info, *temp;
unsigned long flags;
/* FIXME: each batman_if will be attached to a softif */
struct bat_priv *bat_priv = netdev_priv(soft_device);
spin_lock_irqsave(&vis_hash_lock, flags);
purge_vis_packets();
if (generate_vis_packet(bat_priv) == 0) {
/* schedule if generation was successful */
send_list_add(my_vis_info);
}
list_for_each_entry_safe(info, temp, &send_list, send_list) {
kref_get(&info->refcount);
spin_unlock_irqrestore(&vis_hash_lock, flags);
send_vis_packet(info);
spin_lock_irqsave(&vis_hash_lock, flags);
send_list_del(info);
kref_put(&info->refcount, free_info);
}
spin_unlock_irqrestore(&vis_hash_lock, flags);
start_vis_timer();
}
static DECLARE_DELAYED_WORK(vis_timer_wq, send_vis_packets);
/* init the vis server. this may only be called when if_list is already
* initialized (e.g. bat0 is initialized, interfaces have been added) */
int vis_init(void)
{
unsigned long flags;
if (vis_hash)
return 1;
spin_lock_irqsave(&vis_hash_lock, flags);
vis_hash = hash_new(256, vis_info_cmp, vis_info_choose);
if (!vis_hash) {
printk(KERN_ERR "batman-adv:Can't initialize vis_hash\n");
goto err;
}
my_vis_info = kmalloc(1000, GFP_ATOMIC);
if (!my_vis_info) {
printk(KERN_ERR "batman-adv:Can't initialize vis packet\n");
goto err;
}
/* prefill the vis info */
my_vis_info->first_seen = jiffies - atomic_read(&vis_interval);
INIT_LIST_HEAD(&my_vis_info->recv_list);
INIT_LIST_HEAD(&my_vis_info->send_list);
kref_init(&my_vis_info->refcount);
my_vis_info->packet.version = COMPAT_VERSION;
my_vis_info->packet.packet_type = BAT_VIS;
my_vis_info->packet.ttl = TTL;
my_vis_info->packet.seqno = 0;
my_vis_info->packet.entries = 0;
INIT_LIST_HEAD(&send_list);
memcpy(my_vis_info->packet.vis_orig, mainIfAddr, ETH_ALEN);
memcpy(my_vis_info->packet.sender_orig, mainIfAddr, ETH_ALEN);
if (hash_add(vis_hash, my_vis_info) < 0) {
printk(KERN_ERR
"batman-adv:Can't add own vis packet into hash\n");
/* not in hash, need to remove it manually. */
kref_put(&my_vis_info->refcount, free_info);
goto err;
}
spin_unlock_irqrestore(&vis_hash_lock, flags);
start_vis_timer();
return 1;
err:
spin_unlock_irqrestore(&vis_hash_lock, flags);
vis_quit();
return 0;
}
/* Decrease the reference count on a hash item info */
static void free_info_ref(void *data)
{
struct vis_info *info = data;
send_list_del(info);
kref_put(&info->refcount, free_info);
}
/* shutdown vis-server */
void vis_quit(void)
{
unsigned long flags;
if (!vis_hash)
return;
cancel_delayed_work_sync(&vis_timer_wq);
spin_lock_irqsave(&vis_hash_lock, flags);
/* properly remove, kill timers ... */
hash_delete(vis_hash, free_info_ref);
vis_hash = NULL;
my_vis_info = NULL;
spin_unlock_irqrestore(&vis_hash_lock, flags);
}
/* schedule packets for (re)transmission */
static void start_vis_timer(void)
{
queue_delayed_work(bat_event_workqueue, &vis_timer_wq,
(atomic_read(&vis_interval) * HZ) / 1000);
}