[B.A.T.M.A.N.] [PATCH] batman-adv: Revert "Adding netfilter-bridge hooks"

[Sven Eckelmann <sven.eckelmann@gmx.de>]

The netfilter hook seems to be misused and may not filter everything as
expected. Also the ethernet bridge tables are not yet capable to
understand batman-adv packet correctly.

It was only added for testing purposes and can be removed again.

Reported-by: Vasiliy Kulikov <segooon@gmail.com>
Signed-off-by: Sven Eckelmann <sven.eckelmann@gmx.de>
---
I got the information that Linus Luessing acked that change and will
provide that patch for testing purposes somewhere else.

I prefer to get it reverted because it also made the patch
"batman-adv: register the batman-adv packet type per interface"
useless.

 batman-adv/hard-interface.c |   72 +++++++++++++++++++------------------------
 batman-adv/send.c           |    8 +---
 2 files changed, 34 insertions(+), 46 deletions(-)

diff --git a/batman-adv/hard-interface.c b/batman-adv/hard-interface.c
index 063d34d..edbfddf 100644
--- a/batman-adv/hard-interface.c
+++ b/batman-adv/hard-interface.c
@@ -30,7 +30,6 @@
 #include "hash.h"
 
 #include <linux/if_arp.h>
-#include <linux/netfilter_bridge.h>
 
 #include "compat.h"
 
@@ -495,29 +494,46 @@ out:
 	return NOTIFY_DONE;
 }
 
-static int batman_skb_recv_finish(struct sk_buff *skb)
+/* 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)
 {
+	struct bat_priv *bat_priv;
 	struct batman_packet *batman_packet;
 	struct batman_if *batman_if;
-	struct bat_priv *bat_priv;
 	int ret;
 
-	batman_if = get_batman_if_by_netdev(skb->dev);
-	if (!batman_if)
+	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)))
+		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 (!batman_if->soft_iface)
 		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;
 
-	bat_priv = netdev_priv(batman_if->soft_iface);
-	if (atomic_read(&bat_priv->mesh_state) != MESH_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",
@@ -563,42 +579,18 @@ static int batman_skb_recv_finish(struct sk_buff *skb)
 	}
 
 	if (ret == NET_RX_DROP)
-		goto err_free;
+		kfree_skb(skb);
 
-	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;
-}
-
-/* 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;
+	return NET_RX_SUCCESS;
 
-	/* 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);
-	return 0;
+err_out:
+	return NET_RX_DROP;
 }
 
 struct notifier_block hard_if_notifier = {
diff --git a/batman-adv/send.c b/batman-adv/send.c
index 283c6bb..92eb421 100644
--- a/batman-adv/send.c
+++ b/batman-adv/send.c
@@ -29,7 +29,6 @@
 #include "vis.h"
 #include "aggregation.h"
 #include "gateway_common.h"
-#include <linux/netfilter_bridge.h>
 
 #include "compat.h"
 
@@ -94,12 +93,9 @@ 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.
-	 * Also, if netfilter/ebtables wants to block outgoing batman
-	 * packets then giving them a chance to do so here */
+	 * (which is > 0). This will not be treated as an error. */
 
-	return NF_HOOK(PF_BRIDGE, NF_BR_LOCAL_OUT, skb, NULL, skb->dev,
-		       dev_queue_xmit);
+	return dev_queue_xmit(skb);
 send_skb_err:
 	kfree_skb(skb);
 	return NET_XMIT_DROP;
-- 
1.7.1