batman-adv: bla2 & gateway mode interaction fix

Signed-off-by: Marek Lindner <lindner_marek@yahoo.de>



git-svn-id: svn://svn.openwrt.org/openwrt/packages@33064 3c298f89-4303-0410-b956-a3cf2f4a3e73

net/batman-adv/Makefile

@@ -12,7 +12,7 @@ PKG_NAME:=batman-adv
 
 PKG_VERSION:=2012.2.0
 BATCTL_VERSION:=2012.2.0
-PKG_RELEASE:=3
+PKG_RELEASE:=4
 PKG_MD5SUM:=68967ed1df709de18ab795722dde9341
 BATCTL_MD5SUM:=7abd284098c514d3f2858e8a956c495e
 

net/batman-adv/patches/0005-batman-adv-check-incoming-packet-type-for-bla.patch

@@ -0,0 +1,121 @@
+From e32470167379db2ca7713108f1e917c531426eee Mon Sep 17 00:00:00 2001
+From: Simon Wunderlich <simon.wunderlich@s2003.tu-chemnitz.de>
+Date: Wed, 4 Jul 2012 20:38:19 +0200
+Subject: [PATCH] batman-adv: check incoming packet type for bla
+
+If the gateway functionality is used, some broadcast packets (DHCP
+requests) may be transmitted as unicast packets. As the bridge loop
+avoidance code now only considers the payload Ethernet destination,
+it may drop the DHCP request for clients which are claimed by other
+backbone gateways, because it falsely infers from the broadcast address
+that the right backbone gateway should havehandled the broadcast.
+
+Fix this by checking and delegating the batman-adv packet type used
+for transmission.
+
+Reported-by: Guido Iribarren <guidoiribarren@buenosaireslibre.org>
+Signed-off-by: Simon Wunderlich <siwu@hrz.tu-chemnitz.de>
+---
+ bridge_loop_avoidance.c |   15 +++++++++++----
+ bridge_loop_avoidance.h |    5 +++--
+ soft-interface.c        |    6 +++++-
+ 3 files changed, 19 insertions(+), 7 deletions(-)
+
+diff --git a/bridge_loop_avoidance.c b/bridge_loop_avoidance.c
+index 8bf9751..c5863f4 100644
+--- a/bridge_loop_avoidance.c
++++ b/bridge_loop_avoidance.c
+@@ -1351,6 +1351,7 @@ void bla_free(struct bat_priv *bat_priv)
+  * @bat_priv: the bat priv with all the soft interface information
+  * @skb: the frame to be checked
+  * @vid: the VLAN ID of the frame
++ * @is_bcast: the packet came in a broadcast packet type.
+  *
+  * bla_rx avoidance checks if:
+  *  * we have to race for a claim
+@@ -1361,7 +1362,8 @@ void bla_free(struct bat_priv *bat_priv)
+  * process the skb.
+  *
+  */
+-int bla_rx(struct bat_priv *bat_priv, struct sk_buff *skb, short vid)
++int bla_rx(struct bat_priv *bat_priv, struct sk_buff *skb, short vid,
++	   bool is_bcast)
+ {
+ 	struct ethhdr *ethhdr;
+ 	struct claim search_claim, *claim = NULL;
+@@ -1380,7 +1382,7 @@ int bla_rx(struct bat_priv *bat_priv, struct sk_buff *skb, short vid)
+ 
+ 	if (unlikely(atomic_read(&bat_priv->bla_num_requests)))
+ 		/* don't allow broadcasts while requests are in flight */
+-		if (is_multicast_ether_addr(ethhdr->h_dest))
++		if (is_multicast_ether_addr(ethhdr->h_dest) && is_bcast)
+ 			goto handled;
+ 
+ 	memcpy(search_claim.addr, ethhdr->h_source, ETH_ALEN);
+@@ -1406,8 +1408,13 @@ int bla_rx(struct bat_priv *bat_priv, struct sk_buff *skb, short vid)
+ 	}
+ 
+ 	/* if it is a broadcast ... */
+-	if (is_multicast_ether_addr(ethhdr->h_dest)) {
+-		/* ... drop it. the responsible gateway is in charge. */
++	if (is_multicast_ether_addr(ethhdr->h_dest) && is_bcast) {
++		/* ... drop it. the responsible gateway is in charge.
++		 *
++		 * We need to check is_bcast because with the gateway
++		 * feature, broadcasts (like DHCP requests) may be sent
++		 * using a unicast packet type.
++		 */
+ 		goto handled;
+ 	} else {
+ 		/* seems the client considers us as its best gateway.
+diff --git a/bridge_loop_avoidance.h b/bridge_loop_avoidance.h
+index e39f93a..dc5227b 100644
+--- a/bridge_loop_avoidance.h
++++ b/bridge_loop_avoidance.h
+@@ -23,7 +23,8 @@
+ #define _NET_BATMAN_ADV_BLA_H_
+ 
+ #ifdef CONFIG_BATMAN_ADV_BLA
+-int bla_rx(struct bat_priv *bat_priv, struct sk_buff *skb, short vid);
++int bla_rx(struct bat_priv *bat_priv, struct sk_buff *skb, short vid,
++	   bool is_bcast);
+ int bla_tx(struct bat_priv *bat_priv, struct sk_buff *skb, short vid);
+ int bla_is_backbone_gw(struct sk_buff *skb,
+ 		       struct orig_node *orig_node, int hdr_size);
+@@ -41,7 +42,7 @@ void bla_free(struct bat_priv *bat_priv);
+ #else /* ifdef CONFIG_BATMAN_ADV_BLA */
+ 
+ static inline int bla_rx(struct bat_priv *bat_priv, struct sk_buff *skb,
+-			 short vid)
++			 short vid, bool is_bcast)
+ {
+ 	return 0;
+ }
+diff --git a/soft-interface.c b/soft-interface.c
+index 6e2530b..a0ec0e4 100644
+--- a/soft-interface.c
++++ b/soft-interface.c
+@@ -256,7 +256,11 @@ void interface_rx(struct net_device *soft_iface,
+ 	struct bat_priv *bat_priv = netdev_priv(soft_iface);
+ 	struct ethhdr *ethhdr;
+ 	struct vlan_ethhdr *vhdr;
++	struct batman_header *batadv_header = (struct batman_header *)skb->data;
+ 	short vid __maybe_unused = -1;
++	bool is_bcast;
++
++	is_bcast = (batadv_header->packet_type == BAT_BCAST);
+ 
+ 	/* check if enough space is available for pulling, and pull */
+ 	if (!pskb_may_pull(skb, hdr_size))
+@@ -302,7 +306,7 @@ void interface_rx(struct net_device *soft_iface,
+ 	/* Let the bridge loop avoidance check the packet. If will
+ 	 * not handle it, we can safely push it up.
+ 	 */
+-	if (bla_rx(bat_priv, skb, vid))
++	if (bla_rx(bat_priv, skb, vid, is_bcast))
+ 		goto out;
+ 
+ 	netif_rx(skb);
+-- 
+1.7.9.1
+