batman-adv is receiving and sending the packets of its own ether type
on a very early/low level. Therefore we need to add explicit hooks to
give netfilter/ebtables a chance to filter them.
//git revert 660d20261343e0b2ff57e51e50d7eb0e557d5e5b
//Signed-off-by: Linus Lüssing <linus.luessing(a)web.de>
//Reported-by: Antonio Quartulli <ordex(a)ritirata.org>
---
hard-interface.c | 70 ++++++++++++++++++++++++++++++------------------------
send.c | 8 ++++-
2 files changed, 45 insertions(+), 33 deletions(-)
diff --git a/hard-interface.c b/hard-interface.c
index ef95680..9153b19 100644
--- a/hard-interface.c
+++ b/hard-interface.c
@@ -30,6 +30,7 @@
#include "hash.h"
#include <linux/if_arp.h>
+#include <linux/netfilter_bridge.h>
#include "compat.h"
@@ -539,46 +540,29 @@ out:
return NOTIFY_DONE;
}
-/* receive a packet with the batman ethertype coming on a hard
- * interface */
-int batman_skb_recv(struct sk_buff *skb, struct net_device *dev,
- struct packet_type *ptype, struct net_device *orig_dev)
+static int batman_skb_recv_finish(struct sk_buff *skb)
{
- struct bat_priv *bat_priv;
struct batman_packet *batman_packet;
struct batman_if *batman_if;
+ struct bat_priv *bat_priv;
int ret;
- batman_if = container_of(ptype, struct batman_if, batman_adv_ptype);
- skb = skb_share_check(skb, GFP_ATOMIC);
-
- /* skb was released by skb_share_check() */
- if (!skb)
- goto err_out;
-
- /* packet should hold at least type and version */
- if (unlikely(!pskb_may_pull(skb, 2)))
+ batman_if = get_batman_if_by_netdev(skb->dev);
+ if (!batman_if)
goto err_free;
- /* expect a valid ethernet header here. */
- if (unlikely(skb->mac_len != sizeof(struct ethhdr)
- || !skb_mac_header(skb)))
+ if (!batman_if->soft_iface)
goto err_free;
- if (!batman_if->soft_iface)
+ /* discard frames on not active interfaces */
+ if (batman_if->if_status != IF_ACTIVE)
goto err_free;
bat_priv = netdev_priv(batman_if->soft_iface);
-
if (atomic_read(&bat_priv->mesh_state) != MESH_ACTIVE)
goto err_free;
- /* discard frames on not active interfaces */
- if (batman_if->if_status != IF_ACTIVE)
- goto err_free;
-
batman_packet = (struct batman_packet *)skb->data;
-
if (batman_packet->version != COMPAT_VERSION) {
bat_dbg(DBG_BATMAN, bat_priv,
"Drop packet: incompatible batman version (%i)\n",
@@ -624,18 +608,42 @@ int batman_skb_recv(struct sk_buff *skb, struct net_device *dev,
}
if (ret == NET_RX_DROP)
- kfree_skb(skb);
+ goto err_free;
+
+ return 0;
- /* return NET_RX_SUCCESS in any case as we
- * most probably dropped the packet for
- * routing-logical reasons. */
+err_free:
+ kfree_skb(skb);
+ return 0;
+}
- return NET_RX_SUCCESS;
+/* receive a packet with the batman ethertype coming on a hard
+ * interface */
+int batman_skb_recv(struct sk_buff *skb, struct net_device *dev,
+ struct packet_type *ptype, struct net_device *orig_dev)
+{
+ skb = skb_share_check(skb, GFP_ATOMIC);
+ /* skb was released by skb_share_check() */
+ if (!skb)
+ return 0;
+
+ /* packet should hold at least type and version */
+ if (unlikely(!pskb_may_pull(skb, 2)))
+ goto err_free;
+
+ /* expect a valid ethernet header here. */
+ if (unlikely(skb->mac_len != sizeof(struct ethhdr) ||
+ !skb_mac_header(skb)))
+ goto err_free;
+
+ /* if netfilter/ebtables wants to block incoming batman
+ * packets then give them a chance to do so here */
+ return NF_HOOK(PF_BRIDGE, NF_BR_LOCAL_IN, skb, dev,
+ NULL, batman_skb_recv_finish);
err_free:
kfree_skb(skb);
-err_out:
- return NET_RX_DROP;
+ return 0;
}
struct notifier_block hard_if_notifier = {
diff --git a/send.c b/send.c
index a96a786..11a009f 100644
--- a/send.c
+++ b/send.c
@@ -30,6 +30,7 @@
#include "aggregation.h"
#include "gateway_common.h"
#include "originator.h"
+#include <linux/netfilter_bridge.h>
#include "compat.h"
@@ -95,9 +96,12 @@ int send_skb_packet(struct sk_buff *skb,
/* dev_queue_xmit() returns a negative result on error. However on
* congestion and traffic shaping, it drops and returns NET_XMIT_DROP
- * (which is > 0). This will not be treated as an error. */
+ * (which is > 0). This will not be treated as an error.
+ * Also, if netfilter/ebtables wants to block outgoing batman
+ * packets then giving them a chance to do so here */
- return dev_queue_xmit(skb);
+ return NF_HOOK(PF_BRIDGE, NF_BR_LOCAL_OUT, skb, NULL, skb->dev,
+ dev_queue_xmit);
send_skb_err:
kfree_skb(skb);
return NET_XMIT_DROP;
--
1.7.1