/* check for CLAIM frame, return 1 if handled */
static int batadv_handle_claim(struct batadv_priv *bat_priv,
struct batadv_hard_iface *primary_if,
uint8_t *backbone_addr, uint8_t *claim_addr,
unsigned short vid)
{
struct batadv_bla_backbone_gw *backbone_gw;
/* register the gateway if not yet available, and add the claim. */
backbone_gw = batadv_bla_get_backbone_gw(bat_priv, backbone_addr, vid,
false);
if (unlikely(!backbone_gw))
return 1;
/* this must be a CLAIM frame */
batadv_bla_add_claim(bat_priv, claim_addr, vid, backbone_gw);
if (batadv_compare_eth(backbone_addr, primary_if->net_dev->dev_addr))
batadv_bla_send_claim(bat_priv, claim_addr, vid,
BATADV_CLAIM_TYPE_CLAIM);
/* TODO: we could call something like tt_local_del() here. */
batadv_backbone_gw_free_ref(backbone_gw);
return 1;
}
/**
* batadv_bla_is_backbone_gw
* @skb: the frame to be checked
* @orig_node: the orig_node of the frame
* @hdr_size: maximum length of the frame
*
* bla_is_backbone_gw inspects the skb for the VLAN ID and returns 1
* if the orig_node is also a gateway on the soft interface, otherwise it
* returns 0.
*/
int batadv_bla_is_backbone_gw(struct sk_buff *skb,
struct batadv_orig_node *orig_node, int hdr_size)
{
struct ethhdr *ethhdr;
struct vlan_ethhdr *vhdr;
struct batadv_bla_backbone_gw *backbone_gw;
short vid = -1;
if (!atomic_read(&orig_node->bat_priv->bridge_loop_avoidance))
return 0;
/* first, find out the vid. */
if (!pskb_may_pull(skb, hdr_size + ETH_HLEN))
return 0;
ethhdr = (struct ethhdr *)(((uint8_t *)skb->data) + hdr_size);
if (ntohs(ethhdr->h_proto) == ETH_P_8021Q) {
if (!pskb_may_pull(skb, hdr_size + sizeof(struct vlan_ethhdr)))
return 0;
vhdr = (struct vlan_ethhdr *)(skb->data + hdr_size);
vid = ntohs(vhdr->h_vlan_TCI) & VLAN_VID_MASK;
}
/* see if this originator is a backbone gw for this VLAN */
backbone_gw = batadv_backbone_hash_find(orig_node->bat_priv,
orig_node->orig, vid);
if (!backbone_gw)
return 0;
batadv_backbone_gw_free_ref(backbone_gw);
return 1;
}
/* check for UNCLAIM frame, return 1 if handled */
static int batadv_handle_unclaim(struct batadv_priv *bat_priv,
struct batadv_hard_iface *primary_if,
uint8_t *backbone_addr,
uint8_t *claim_addr, unsigned short vid)
{
struct batadv_bla_backbone_gw *backbone_gw;
/* unclaim in any case if it is our own */
if (primary_if && batadv_compare_eth(backbone_addr,
primary_if->net_dev->dev_addr))
batadv_bla_send_claim(bat_priv, claim_addr, vid,
BATADV_CLAIM_TYPE_UNCLAIM);
backbone_gw = batadv_backbone_hash_find(bat_priv, backbone_addr, vid);
if (!backbone_gw)
return 1;
/* this must be an UNCLAIM frame */
batadv_dbg(BATADV_DBG_BLA, bat_priv,
"handle_unclaim(): UNCLAIM %pM on vid %d (sent by %pM)...\n",
claim_addr, BATADV_PRINT_VID(vid), backbone_gw->orig);
batadv_bla_del_claim(bat_priv, claim_addr, vid);
batadv_backbone_gw_free_ref(backbone_gw);
return 1;
}
/**
* batadv_bla_add_claim - Adds a claim in the claim hash
* @bat_priv: the bat priv with all the soft interface information
* @mac: the mac address of the claim
* @vid: the VLAN ID of the frame
* @backbone_gw: the backbone gateway which claims it
*/
static void batadv_bla_add_claim(struct batadv_priv *bat_priv,
const uint8_t *mac, const unsigned short vid,
struct batadv_bla_backbone_gw *backbone_gw)
{
struct batadv_bla_claim *claim;
struct batadv_bla_claim search_claim;
int hash_added;
ether_addr_copy(search_claim.addr, mac);
search_claim.vid = vid;
claim = batadv_claim_hash_find(bat_priv, &search_claim);
/* create a new claim entry if it does not exist yet. */
if (!claim) {
claim = kzalloc(sizeof(*claim), GFP_ATOMIC);
if (!claim)
return;
ether_addr_copy(claim->addr, mac);
claim->vid = vid;
claim->lasttime = jiffies;
claim->backbone_gw = backbone_gw;
atomic_set(&claim->refcount, 2);
batadv_dbg(BATADV_DBG_BLA, bat_priv,
"bla_add_claim(): adding new entry %pM, vid %d to hash ...\n",
mac, BATADV_PRINT_VID(vid));
hash_added = batadv_hash_add(bat_priv->bla.claim_hash,
batadv_compare_claim,
batadv_choose_claim, claim,
&claim->hash_entry);
if (unlikely(hash_added != 0)) {
/* only local changes happened. */
kfree(claim);
return;
}
} else {
claim->lasttime = jiffies;
if (claim->backbone_gw == backbone_gw)
/* no need to register a new backbone */
goto claim_free_ref;
batadv_dbg(BATADV_DBG_BLA, bat_priv,
"bla_add_claim(): changing ownership for %pM, vid %d\n",
mac, BATADV_PRINT_VID(vid));
claim->backbone_gw->crc ^= crc16(0, claim->addr, ETH_ALEN);
batadv_backbone_gw_free_ref(claim->backbone_gw);
}
/* set (new) backbone gw */
atomic_inc(&backbone_gw->refcount);
claim->backbone_gw = backbone_gw;
backbone_gw->crc ^= crc16(0, claim->addr, ETH_ALEN);
backbone_gw->lasttime = jiffies;
claim_free_ref:
batadv_claim_free_ref(claim);
}
/* finally deinitialize the claim */
static void batadv_claim_free_rcu(struct rcu_head *rcu)
{
struct batadv_bla_claim *claim;
claim = container_of(rcu, struct batadv_bla_claim, rcu);
batadv_backbone_gw_free_ref(claim->backbone_gw);
kfree(claim);
}
/* update or add the own backbone gw to make sure we announce
* where we receive other backbone gws
*/
static void
batadv_bla_update_own_backbone_gw(struct batadv_priv *bat_priv,
struct batadv_hard_iface *primary_if,
unsigned short vid)
{
struct batadv_bla_backbone_gw *backbone_gw;
backbone_gw = batadv_bla_get_backbone_gw(bat_priv,
primary_if->net_dev->dev_addr,
vid, true);
if (unlikely(!backbone_gw))
return;
backbone_gw->lasttime = jiffies;
batadv_backbone_gw_free_ref(backbone_gw);
}
/* check for ANNOUNCE frame, return 1 if handled */
static int batadv_handle_announce(struct batadv_priv *bat_priv,
uint8_t *an_addr, uint8_t *backbone_addr,
unsigned short vid)
{
struct batadv_bla_backbone_gw *backbone_gw;
uint16_t crc;
if (memcmp(an_addr, batadv_announce_mac, 4) != 0)
return 0;
backbone_gw = batadv_bla_get_backbone_gw(bat_priv, backbone_addr, vid,
false);
if (unlikely(!backbone_gw))
return 1;
/* handle as ANNOUNCE frame */
backbone_gw->lasttime = jiffies;
crc = ntohs(*((__be16 *)(&an_addr[4])));
batadv_dbg(BATADV_DBG_BLA, bat_priv,
"handle_announce(): ANNOUNCE vid %d (sent by %pM)... CRC = %#.4x\n",
BATADV_PRINT_VID(vid), backbone_gw->orig, crc);
if (backbone_gw->crc != crc) {
batadv_dbg(BATADV_DBG_BLA, backbone_gw->bat_priv,
"handle_announce(): CRC FAILED for %pM/%d (my = %#.4x, sent = %#.4x)\n",
backbone_gw->orig,
BATADV_PRINT_VID(backbone_gw->vid),
backbone_gw->crc, crc);
batadv_bla_send_request(backbone_gw);
} else {
/* if we have sent a request and the crc was OK,
* we can allow traffic again.
*/
if (atomic_read(&backbone_gw->request_sent)) {
atomic_dec(&backbone_gw->bat_priv->bla.num_requests);
atomic_set(&backbone_gw->request_sent, 0);
}
}
batadv_backbone_gw_free_ref(backbone_gw);
return 1;
}
/* Check when we last heard from other nodes, and remove them in case of
* a time out, or clean all backbone gws if now is set.
*/
static void batadv_bla_purge_backbone_gw(struct batadv_priv *bat_priv, int now)
{
struct batadv_bla_backbone_gw *backbone_gw;
struct hlist_node *node_tmp;
struct hlist_head *head;
struct batadv_hashtable *hash;
spinlock_t *list_lock; /* protects write access to the hash lists */
int i;
hash = bat_priv->bla.backbone_hash;
if (!hash)
return;
for (i = 0; i < hash->size; i++) {
head = &hash->table[i];
list_lock = &hash->list_locks[i];
spin_lock_bh(list_lock);
hlist_for_each_entry_safe(backbone_gw, node_tmp,
head, hash_entry) {
if (now)
goto purge_now;
if (!batadv_has_timed_out(backbone_gw->lasttime,
BATADV_BLA_BACKBONE_TIMEOUT))
continue;
batadv_dbg(BATADV_DBG_BLA, backbone_gw->bat_priv,
"bla_purge_backbone_gw(): backbone gw %pM timed out\n",
backbone_gw->orig);
purge_now:
/* don't wait for the pending request anymore */
if (atomic_read(&backbone_gw->request_sent))
atomic_dec(&bat_priv->bla.num_requests);
batadv_bla_del_backbone_claims(backbone_gw);
hlist_del_rcu(&backbone_gw->hash_entry);
batadv_backbone_gw_free_ref(backbone_gw);
}
spin_unlock_bh(list_lock);
}
}
/* @bat_priv: the bat priv with all the soft interface information
* @vid: the vid where the request came on
*
* Repeat all of our own claims, and finally send an ANNOUNCE frame
* to allow the requester another check if the CRC is correct now.
*/
static void batadv_bla_answer_request(struct batadv_priv *bat_priv,
struct batadv_hard_iface *primary_if,
short vid)
{
struct hlist_node *node;
struct hlist_head *head;
struct batadv_hashtable *hash;
struct batadv_claim *claim;
struct batadv_backbone_gw *backbone_gw;
int i;
batadv_dbg(BATADV_DBG_BLA, bat_priv,
"bla_answer_request(): received a claim request, send all of our own claims again\n");
backbone_gw = batadv_backbone_hash_find(bat_priv,
primary_if->net_dev->dev_addr,
vid);
if (!backbone_gw)
return;
hash = bat_priv->bla.claim_hash;
for (i = 0; i < hash->size; i++) {
head = &hash->table[i];
rcu_read_lock();
hlist_for_each_entry_rcu(claim, node, head, hash_entry) {
/* only own claims are interesting */
if (claim->backbone_gw != backbone_gw)
continue;
batadv_bla_send_claim(bat_priv, claim->addr, claim->vid,
BATADV_CLAIM_TYPE_CLAIM);
}
rcu_read_unlock();
}
/* finally, send an announcement frame */
batadv_bla_send_announce(bat_priv, backbone_gw);
batadv_backbone_gw_free_ref(backbone_gw);
}
/**
* batadv_bla_is_backbone_gw
* @skb: the frame to be checked
* @orig_node: the orig_node of the frame
* @hdr_size: maximum length of the frame
*
* bla_is_backbone_gw inspects the skb for the VLAN ID and returns 1
* if the orig_node is also a gateway on the soft interface, otherwise it
* returns 0.
*/
int batadv_bla_is_backbone_gw(struct sk_buff *skb,
struct batadv_orig_node *orig_node, int hdr_size)
{
struct batadv_bla_backbone_gw *backbone_gw;
unsigned short vid;
if (!atomic_read(&orig_node->bat_priv->bridge_loop_avoidance))
return 0;
/* first, find out the vid. */
if (!pskb_may_pull(skb, hdr_size + ETH_HLEN))
return 0;
vid = batadv_get_vid(skb, hdr_size);
/* see if this originator is a backbone gw for this VLAN */
backbone_gw = batadv_backbone_hash_find(orig_node->bat_priv,
orig_node->orig, vid);
if (!backbone_gw)
return 0;
batadv_backbone_gw_free_ref(backbone_gw);
return 1;
}
/* finally deinitialize the claim */
static void batadv_claim_release(struct batadv_bla_claim *claim)
{
batadv_backbone_gw_free_ref(claim->backbone_gw);
kfree_rcu(claim, rcu);
}
