batman-adv: Explicitly mark the common header structure
All batman-adv packets have a common 3 byte header. It can be used to share
some code between different code paths, but it was never explicit stated that
this header has to be always the same for all packets. Therefore, new code
changes always have the problem that they may accidently introduce regressions
by moving some elements around.
A new structure is introduced that contains the common header and makes it
easier visible that these 3 bytes have to be the same for all on-wire packets.
Signed-off-by: Sven Eckelmann <sven@narfation.org>
Signed-off-by: Marek Lindner <lindner_marek@yahoo.de>
diff --git a/net/batman-adv/bat_iv_ogm.c b/net/batman-adv/bat_iv_ogm.c
index 3512e25..d60e1ba 100644
--- a/net/batman-adv/bat_iv_ogm.c
+++ b/net/batman-adv/bat_iv_ogm.c
@@ -38,10 +38,10 @@
hard_iface->packet_buff = kmalloc(hard_iface->packet_len, GFP_ATOMIC);
batman_ogm_packet = (struct batman_ogm_packet *)hard_iface->packet_buff;
- batman_ogm_packet->packet_type = BAT_OGM;
- batman_ogm_packet->version = COMPAT_VERSION;
+ batman_ogm_packet->header.packet_type = BAT_OGM;
+ batman_ogm_packet->header.version = COMPAT_VERSION;
+ batman_ogm_packet->header.ttl = 2;
batman_ogm_packet->flags = NO_FLAGS;
- batman_ogm_packet->ttl = 2;
batman_ogm_packet->tq = TQ_MAX_VALUE;
batman_ogm_packet->tt_num_changes = 0;
batman_ogm_packet->ttvn = 0;
@@ -53,7 +53,7 @@
batman_ogm_packet = (struct batman_ogm_packet *)hard_iface->packet_buff;
batman_ogm_packet->flags = PRIMARIES_FIRST_HOP;
- batman_ogm_packet->ttl = TTL;
+ batman_ogm_packet->header.ttl = TTL;
}
void bat_ogm_update_mac(struct hard_iface *hard_iface)
@@ -137,7 +137,7 @@
fwd_str, (packet_num > 0 ? "aggregated " : ""),
batman_ogm_packet->orig,
ntohl(batman_ogm_packet->seqno),
- batman_ogm_packet->tq, batman_ogm_packet->ttl,
+ batman_ogm_packet->tq, batman_ogm_packet->header.ttl,
(batman_ogm_packet->flags & DIRECTLINK ?
"on" : "off"),
batman_ogm_packet->ttvn, hard_iface->net_dev->name,
@@ -188,7 +188,7 @@
/* multihomed peer assumed */
/* non-primary OGMs are only broadcasted on their interface */
- if ((directlink && (batman_ogm_packet->ttl == 1)) ||
+ if ((directlink && (batman_ogm_packet->header.ttl == 1)) ||
(forw_packet->own && (forw_packet->if_incoming != primary_if))) {
/* FIXME: what about aggregated packets ? */
@@ -198,7 +198,7 @@
(forw_packet->own ? "Sending own" : "Forwarding"),
batman_ogm_packet->orig,
ntohl(batman_ogm_packet->seqno),
- batman_ogm_packet->ttl,
+ batman_ogm_packet->header.ttl,
forw_packet->if_incoming->net_dev->name,
forw_packet->if_incoming->net_dev->dev_addr);
@@ -272,7 +272,7 @@
* are flooded through the net */
if ((!directlink) &&
(!(batman_ogm_packet->flags & DIRECTLINK)) &&
- (batman_ogm_packet->ttl != 1) &&
+ (batman_ogm_packet->header.ttl != 1) &&
/* own packets originating non-primary
* interfaces leave only that interface */
@@ -285,7 +285,7 @@
/* if the incoming packet is sent via this one
* interface only - we still can aggregate */
if ((directlink) &&
- (new_batman_ogm_packet->ttl == 1) &&
+ (new_batman_ogm_packet->header.ttl == 1) &&
(forw_packet->if_incoming == if_incoming) &&
/* packets from direct neighbors or
@@ -471,7 +471,7 @@
uint8_t in_tq, in_ttl, tq_avg = 0;
uint8_t tt_num_changes;
- if (batman_ogm_packet->ttl <= 1) {
+ if (batman_ogm_packet->header.ttl <= 1) {
bat_dbg(DBG_BATMAN, bat_priv, "ttl exceeded\n");
return;
}
@@ -479,10 +479,10 @@
router = orig_node_get_router(orig_node);
in_tq = batman_ogm_packet->tq;
- in_ttl = batman_ogm_packet->ttl;
+ in_ttl = batman_ogm_packet->header.ttl;
tt_num_changes = batman_ogm_packet->tt_num_changes;
- batman_ogm_packet->ttl--;
+ batman_ogm_packet->header.ttl--;
memcpy(batman_ogm_packet->prev_sender, ethhdr->h_source, ETH_ALEN);
/* rebroadcast tq of our best ranking neighbor to ensure the rebroadcast
@@ -494,7 +494,8 @@
batman_ogm_packet->tq = router->tq_avg;
if (router->last_ttl)
- batman_ogm_packet->ttl = router->last_ttl - 1;
+ batman_ogm_packet->header.ttl =
+ router->last_ttl - 1;
}
tq_avg = router->tq_avg;
@@ -510,7 +511,7 @@
"Forwarding packet: tq_orig: %i, tq_avg: %i, "
"tq_forw: %i, ttl_orig: %i, ttl_forw: %i\n",
in_tq, tq_avg, batman_ogm_packet->tq, in_ttl - 1,
- batman_ogm_packet->ttl);
+ batman_ogm_packet->header.ttl);
batman_ogm_packet->seqno = htonl(batman_ogm_packet->seqno);
batman_ogm_packet->tt_crc = htons(batman_ogm_packet->tt_crc);
@@ -642,8 +643,8 @@
spin_unlock_bh(&neigh_node->tq_lock);
if (!is_duplicate) {
- orig_node->last_ttl = batman_ogm_packet->ttl;
- neigh_node->last_ttl = batman_ogm_packet->ttl;
+ orig_node->last_ttl = batman_ogm_packet->header.ttl;
+ neigh_node->last_ttl = batman_ogm_packet->header.ttl;
}
bonding_candidate_add(orig_node, neigh_node);
@@ -683,7 +684,7 @@
/* I have to check for transtable changes only if the OGM has been
* sent through a primary interface */
if (((batman_ogm_packet->orig != ethhdr->h_source) &&
- (batman_ogm_packet->ttl > 2)) ||
+ (batman_ogm_packet->header.ttl > 2)) ||
(batman_ogm_packet->flags & PRIMARIES_FIRST_HOP))
tt_update_orig(bat_priv, orig_node, tt_buff,
batman_ogm_packet->tt_num_changes,
@@ -918,7 +919,7 @@
* packet in an aggregation. Here we expect that the padding
* is always zero (or not 0x01)
*/
- if (batman_ogm_packet->packet_type != BAT_OGM)
+ if (batman_ogm_packet->header.packet_type != BAT_OGM)
return;
/* could be changed by schedule_own_packet() */
@@ -938,8 +939,8 @@
batman_ogm_packet->prev_sender, batman_ogm_packet->seqno,
batman_ogm_packet->ttvn, batman_ogm_packet->tt_crc,
batman_ogm_packet->tt_num_changes, batman_ogm_packet->tq,
- batman_ogm_packet->ttl, batman_ogm_packet->version,
- has_directlink_flag);
+ batman_ogm_packet->header.ttl,
+ batman_ogm_packet->header.version, has_directlink_flag);
rcu_read_lock();
list_for_each_entry_rcu(hard_iface, &hardif_list, list) {
@@ -966,10 +967,10 @@
}
rcu_read_unlock();
- if (batman_ogm_packet->version != COMPAT_VERSION) {
+ if (batman_ogm_packet->header.version != COMPAT_VERSION) {
bat_dbg(DBG_BATMAN, bat_priv,
"Drop packet: incompatible batman version (%i)\n",
- batman_ogm_packet->version);
+ batman_ogm_packet->header.version);
return;
}
@@ -1091,7 +1092,7 @@
if (is_bidirectional &&
(!is_duplicate ||
((orig_node->last_real_seqno == batman_ogm_packet->seqno) &&
- (orig_node->last_ttl - 3 <= batman_ogm_packet->ttl))))
+ (orig_node->last_ttl - 3 <= batman_ogm_packet->header.ttl))))
bat_ogm_orig_update(bat_priv, orig_node, ethhdr,
batman_ogm_packet, if_incoming,
tt_buff, is_duplicate);