From 951b6632bcdd29490c111a79285911795adb41cb Mon Sep 17 00:00:00 2001
From: =?UTF-8?q?Linus=20L=C3=BCssing?= <linus.luessing@c0d3.blue>
Date: Sat, 31 Mar 2018 19:12:43 +0200
Subject: [PATCH] gluon-ebtables-limit-arp: do not add multicast addresses to
filter
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With the batman-adv multicast support compiled back in again we end up
with multicast addresses in the batman-adv translation table.
Currently we wrongly interpret multicast addresses returned by TT as a
unique host, too, which adds them with a source address filter to
ebtables as well. However, the source address of an ethernet frames is
never supposed to be a multicat one.
This leads to unnecessary entries in ebtables. Fixing this by ignoring
those MAC addreses returned by TT which have the multicast bit set.
Signed-off-by: Linus Lüssing <linus.luessing@c0d3.blue>
---
package/gluon-ebtables-limit-arp/src/gluon-arp-limiter.c | 3 +++
package/gluon-ebtables-limit-arp/src/mac.h | 5 +++++
2 files changed, 8 insertions(+)
diff --git a/package/gluon-ebtables-limit-arp/src/gluon-arp-limiter.c b/package/gluon-ebtables-limit-arp/src/gluon-arp-limiter.c
index af4acf48d..cbb6faf21 100644
--- a/package/gluon-ebtables-limit-arp/src/gluon-arp-limiter.c
+++ b/package/gluon-ebtables-limit-arp/src/gluon-arp-limiter.c
@@ -248,6 +248,9 @@ static void ebt_tl_update(void)
break;
}
+ if (mac_is_multicast(&mac))
+ continue;
+
ebt_add_mac(&mac);
}
diff --git a/package/gluon-ebtables-limit-arp/src/mac.h b/package/gluon-ebtables-limit-arp/src/mac.h
index e61917364..11567ade6 100644
--- a/package/gluon-ebtables-limit-arp/src/mac.h
+++ b/package/gluon-ebtables-limit-arp/src/mac.h
@@ -16,4 +16,9 @@ struct mac_addr {
int mac_aton(const char *cp, struct mac_addr *mac);
char *mac_ntoa(struct mac_addr *mac);
+static inline int mac_is_multicast(struct mac_addr *addr)
+{
+ return addr->storage[0] & 0x01;
+}
+
#endif /* _MAC_H_ */
--
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