[B.A.T.M.A.N.] [PATCH 02/21] batman-adv: add seqno maximum age and protection start flag parameters

Antonio Quartulli
2016-02-10T15:57:08Z

From: Simon Wunderlich <simon@open-mesh.com>

To allow future use of the window protected function with different
maximum sequence numbers, add a parameter to set this value which
was previously hardcoded. Another parameter added for future use is a
flag to return whether the protection window has started.

While at it, also fix the kerneldoc.

Signed-off-by: Simon Wunderlich <simon@open-mesh.com>
Signed-off-by: Marek Lindner <mareklindner@neomailbox.ch>
Signed-off-by: Antonio Quartulli <a@unstable.cc>
---
net/batman-adv/bat_iv_ogm.c | 3 ++-
net/batman-adv/main.h | 3 +++
net/batman-adv/routing.c | 13 ++++++++++---
net/batman-adv/routing.h | 3 ++-
4 files changed, 17 insertions(+), 5 deletions(-)

diff --git a/net/batman-adv/bat_iv_ogm.c b/net/batman-adv/bat_iv_ogm.c
index 3266bcb5bb06..23ce90e21a40 100644
--- a/net/batman-adv/bat_iv_ogm.c
+++ b/net/batman-adv/bat_iv_ogm.c
@@ -1315,7 +1315,8 @@ batadv_iv_ogm_update_seqnos(const struct ethhdr *ethhdr,
/* signalize caller that the packet is to be dropped. */
if (!hlist_empty(&orig_node->neigh_list) &&
batadv_window_protected(bat_priv, seq_diff,
- &orig_ifinfo->batman_seqno_reset)) {
+ BATADV_TQ_LOCAL_WINDOW_SIZE,
+ &orig_ifinfo->batman_seqno_reset, NULL)) {
ret = BATADV_PROTECTED;
goto out;
}
diff --git a/net/batman-adv/main.h b/net/batman-adv/main.h
index a7dc41a2709b..32dfc9e578af 100644
--- a/net/batman-adv/main.h
+++ b/net/batman-adv/main.h
@@ -35,6 +35,9 @@
/* Time To Live of broadcast messages */
#define BATADV_TTL 50

+/* maximum sequence number age of broadcast messages */
+#define BATADV_BCAST_MAX_AGE 64
+
/* purge originators after time in seconds if no valid packet comes in
* -> TODO: check influence on BATADV_TQ_LOCAL_WINDOW_SIZE
*/
diff --git a/net/batman-adv/routing.c b/net/batman-adv/routing.c
index f4b60b1fb50e..1c8b35df50cf 100644
--- a/net/batman-adv/routing.c
+++ b/net/batman-adv/routing.c
@@ -146,23 +146,29 @@ out:
* @bat_priv: the bat priv with all the soft interface information
* @seq_num_diff: difference between the current/received sequence number and
* the last sequence number
+ * @seq_old_max_diff: maximum age of sequence number not considered as restart
* @last_reset: jiffies timestamp of the last reset, will be updated when reset
* is detected
+ * @protection_started: is set to true if the protection window was started,
+ * doesn't change otherwise.
*
* Return:
* 0 if the packet is to be accepted.
* 1 if the packet is to be ignored.
*/
int batadv_window_protected(struct batadv_priv *bat_priv, s32 seq_num_diff,
- unsigned long *last_reset)
+ s32 seq_old_max_diff, unsigned long *last_reset,
+ bool *protection_started)
{
- if (seq_num_diff <= -BATADV_TQ_LOCAL_WINDOW_SIZE ||
+ if (seq_num_diff <= -seq_old_max_diff ||
seq_num_diff >= BATADV_EXPECTED_SEQNO_RANGE) {
if (!batadv_has_timed_out(*last_reset,
BATADV_RESET_PROTECTION_MS))
return 1;

*last_reset = jiffies;
+ if (protection_started)
+ *protection_started = true;
batadv_dbg(BATADV_DBG_BATMAN, bat_priv,
"old packet received, start protection\n");
}
@@ -1073,7 +1079,8 @@ int batadv_recv_bcast_packet(struct sk_buff *skb,

/* check whether the packet is old and the host just restarted. */
if (batadv_window_protected(bat_priv, seq_diff,
- &orig_node->bcast_seqno_reset))
+ BATADV_BCAST_MAX_AGE,
+ &orig_node->bcast_seqno_reset, NULL))
goto spin_unlock;

/* mark broadcast in flood history, update window position
diff --git a/net/batman-adv/routing.h b/net/batman-adv/routing.h
index c776e9655b9b..02a5caa84127 100644
--- a/net/batman-adv/routing.h
+++ b/net/batman-adv/routing.h
@@ -52,6 +52,7 @@ batadv_find_router(struct batadv_priv *bat_priv,
struct batadv_orig_node *orig_node,
struct batadv_hard_iface *recv_if);
int batadv_window_protected(struct batadv_priv *bat_priv, s32 seq_num_diff,
- unsigned long *last_reset);
+ s32 seq_old_max_diff, unsigned long *last_reset,
+ bool *protection_started);

#endif /* _NET_BATMAN_ADV_ROUTING_H_ */
--
2.7.1