From 28658c8967da9083be83af0a37be3b190bae79da Mon Sep 17 00:00:00 2001
From: Phil Oester <kernel@linuxace.com>
Date: Mon, 24 Jul 2006 22:54:14 -0700
Subject: [PATCH] [NETFILTER]: xt_pkttype: fix mismatches on locally generated
packets
Locally generated broadcast and multicast packets have pkttype set to
PACKET_LOOPBACK instead of PACKET_BROADCAST or PACKET_MULTICAST. This
causes the pkttype match to fail to match packets of either type.
The below patch remedies this by using the daddr as a hint as to
broadcast|multicast. While not pretty, this seems like the only way
to solve the problem short of just noting this as a limitation of the
match.
This resolves netfilter bugzilla #484
Signed-off-by: Phil Oester <kernel@linuxace.com>
Signed-off-by: Patrick McHardy <kaber@trash.net>
Signed-off-by: David S. Miller <davem@davemloft.net>
---
net/netfilter/xt_pkttype.c | 12 +++++++++++-
1 file changed, 11 insertions(+), 1 deletion(-)
diff --git a/net/netfilter/xt_pkttype.c b/net/netfilter/xt_pkttype.c
index 3ac703b5cb8ff..d2f5320a80bf6 100644
--- a/net/netfilter/xt_pkttype.c
+++ b/net/netfilter/xt_pkttype.c
@@ -9,6 +9,8 @@
#include <linux/skbuff.h>
#include <linux/if_ether.h>
#include <linux/if_packet.h>
+#include <linux/in.h>
+#include <linux/ip.h>
#include <linux/netfilter/xt_pkttype.h>
#include <linux/netfilter/x_tables.h>
@@ -28,9 +30,17 @@ static int match(const struct sk_buff *skb,
unsigned int protoff,
int *hotdrop)
{
+ u_int8_t type;
const struct xt_pkttype_info *info = matchinfo;
- return (skb->pkt_type == info->pkttype) ^ info->invert;
+ if (skb->pkt_type == PACKET_LOOPBACK)
+ type = (MULTICAST(skb->nh.iph->daddr)
+ ? PACKET_MULTICAST
+ : PACKET_BROADCAST);
+ else
+ type = skb->pkt_type;
+
+ return (type == info->pkttype) ^ info->invert;
}
static struct xt_match pkttype_match = {
--
2.30.2