batman-adv: tvlv - basic infrastructure
The goal is to provide the infrastructure for sending, receiving and
parsing information 'containers' while preserving backward
compatibility. TVLV (based on the commonly known Type Length Value
technique) was chosen as the format for those containers. Even if a
node does not know the tvlv type of a certain container it can simply
skip the current container and proceed with the next. Past experience
has shown features evolve over time, so a 'version' field was added
right from the start to allow differentiating between feature
variants - hence the name: T(ype) V(ersion) L(ength) V(alue).
This patch introduces the basic TVLV infrastructure:
* register / unregister tvlv containers to be sent with each OGM
(on primary interfaces only)
* register / unregister callback handlers to be called upon
finding the corresponding tvlv type in a tvlv buffer
* unicast tvlv send / receive API calls
Signed-off-by: Marek Lindner <lindner_marek@yahoo.de>
Signed-off-by: Spyros Gasteratos <morfeas3000@gmail.com>
Signed-off-by: Antonio Quartulli <antonio@meshcoding.com>
diff --git a/net/batman-adv/bat_iv_ogm.c b/net/batman-adv/bat_iv_ogm.c
index 0a8a80c..f7dd7e5 100644
--- a/net/batman-adv/bat_iv_ogm.c
+++ b/net/batman-adv/bat_iv_ogm.c
@@ -207,12 +207,12 @@
/* is there another aggregated packet here? */
static int batadv_iv_ogm_aggr_packet(int buff_pos, int packet_len,
- int tt_num_changes)
+ __be16 tvlv_len)
{
int next_buff_pos = 0;
next_buff_pos += buff_pos + BATADV_OGM_HLEN;
- next_buff_pos += batadv_tt_len(tt_num_changes);
+ next_buff_pos += ntohs(tvlv_len);
return (next_buff_pos <= packet_len) &&
(next_buff_pos <= BATADV_MAX_AGGREGATION_BYTES);
@@ -240,7 +240,7 @@
/* adjust all flags and log packets */
while (batadv_iv_ogm_aggr_packet(buff_pos, forw_packet->packet_len,
- batadv_ogm_packet->tt_num_changes)) {
+ batadv_ogm_packet->tvlv_len)) {
/* we might have aggregated direct link packets with an
* ordinary base packet
*/
@@ -267,7 +267,7 @@
hard_iface->net_dev->dev_addr);
buff_pos += BATADV_OGM_HLEN;
- buff_pos += batadv_tt_len(batadv_ogm_packet->tt_num_changes);
+ buff_pos += ntohs(batadv_ogm_packet->tvlv_len);
packet_num++;
packet_pos = forw_packet->skb->data + buff_pos;
batadv_ogm_packet = (struct batadv_ogm_packet *)packet_pos;
@@ -601,7 +601,7 @@
struct batadv_hard_iface *if_incoming)
{
struct batadv_priv *bat_priv = netdev_priv(if_incoming->soft_iface);
- uint8_t tt_num_changes;
+ uint16_t tvlv_len;
if (batadv_ogm_packet->header.ttl <= 1) {
batadv_dbg(BATADV_DBG_BATMAN, bat_priv, "ttl exceeded\n");
@@ -621,7 +621,7 @@
return;
}
- tt_num_changes = batadv_ogm_packet->tt_num_changes;
+ tvlv_len = ntohs(batadv_ogm_packet->tvlv_len);
batadv_ogm_packet->header.ttl--;
memcpy(batadv_ogm_packet->prev_sender, ethhdr->h_source, ETH_ALEN);
@@ -642,7 +642,7 @@
batadv_ogm_packet->flags &= ~BATADV_DIRECTLINK;
batadv_iv_ogm_queue_add(bat_priv, (unsigned char *)batadv_ogm_packet,
- BATADV_OGM_HLEN + batadv_tt_len(tt_num_changes),
+ BATADV_OGM_HLEN + tvlv_len,
if_incoming, 0, batadv_iv_ogm_fwd_send_time());
}
@@ -691,16 +691,18 @@
int vis_server, tt_num_changes = 0;
uint32_t seqno;
uint8_t bandwidth;
+ uint16_t tvlv_len = 0;
vis_server = atomic_read(&bat_priv->vis_mode);
primary_if = batadv_primary_if_get_selected(bat_priv);
if (hard_iface == primary_if)
- tt_num_changes = batadv_tt_append_diff(bat_priv, ogm_buff,
- ogm_buff_len,
- BATADV_OGM_HLEN);
+ tvlv_len = batadv_tvlv_container_ogm_append(bat_priv, ogm_buff,
+ ogm_buff_len,
+ BATADV_OGM_HLEN);
batadv_ogm_packet = (struct batadv_ogm_packet *)(*ogm_buff);
+ batadv_ogm_packet->tvlv_len = htons(tvlv_len);
/* change sequence number to network order */
seqno = (uint32_t)atomic_read(&hard_iface->bat_iv.ogm_seqno);
@@ -1254,6 +1256,8 @@
goto out;
}
+ batadv_tvlv_ogm_receive(bat_priv, batadv_ogm_packet, orig_node);
+
/* if sender is a direct neighbor the sender mac equals
* originator mac
*/
@@ -1350,9 +1354,9 @@
struct batadv_ogm_packet *batadv_ogm_packet;
struct ethhdr *ethhdr;
int buff_pos = 0, packet_len;
- unsigned char *tt_buff, *packet_buff;
- bool ret;
+ unsigned char *tvlv_buff, *packet_buff;
uint8_t *packet_pos;
+ bool ret;
ret = batadv_check_management_packet(skb, if_incoming, BATADV_OGM_HLEN);
if (!ret)
@@ -1375,14 +1379,14 @@
/* unpack the aggregated packets and process them one by one */
while (batadv_iv_ogm_aggr_packet(buff_pos, packet_len,
- batadv_ogm_packet->tt_num_changes)) {
- tt_buff = packet_buff + buff_pos + BATADV_OGM_HLEN;
+ batadv_ogm_packet->tvlv_len)) {
+ tvlv_buff = packet_buff + buff_pos + BATADV_OGM_HLEN;
- batadv_iv_ogm_process(ethhdr, batadv_ogm_packet, tt_buff,
- if_incoming);
+ batadv_iv_ogm_process(ethhdr, batadv_ogm_packet,
+ tvlv_buff, if_incoming);
buff_pos += BATADV_OGM_HLEN;
- buff_pos += batadv_tt_len(batadv_ogm_packet->tt_num_changes);
+ buff_pos += ntohs(batadv_ogm_packet->tvlv_len);
packet_pos = packet_buff + buff_pos;
batadv_ogm_packet = (struct batadv_ogm_packet *)packet_pos;