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.
Signed-off-by: Linus Lüssing linus.luessing@web.de Reported-by: Antonio Quartulli ordex@ritirata.org --- batman-adv-kernelland/hard-interface.c | 17 +++++++++++++++-- batman-adv-kernelland/send.c | 8 ++++++-- 2 files changed, 21 insertions(+), 4 deletions(-)
diff --git a/batman-adv-kernelland/hard-interface.c b/batman-adv-kernelland/hard-interface.c index cc7fbae..6a64930 100644 --- a/batman-adv-kernelland/hard-interface.c +++ b/batman-adv-kernelland/hard-interface.c @@ -28,9 +28,11 @@ #include "bat_sysfs.h" #include "originator.h" #include "hash.h" -#include "compat.h"
#include <linux/if_arp.h> +#include <linux/netfilter_bridge.h> + +#include "compat.h"
#define MIN(x, y) ((x) < (y) ? (x) : (y))
@@ -433,6 +435,11 @@ out: return NOTIFY_DONE; }
+int batman_skb_recv_finish(struct sk_buff *skb) +{ + return NF_ACCEPT; +} + /* receive a packet with the batman ethertype coming on a hard * interface */ int batman_skb_recv(struct sk_buff *skb, struct net_device *dev, @@ -452,6 +459,13 @@ int batman_skb_recv(struct sk_buff *skb, struct net_device *dev, if (atomic_read(&module_state) != MODULE_ACTIVE) goto err_free;
+ /* if netfilter/ebtables wants to block incoming batman + * packets then give them a chance to do so here */ + ret = NF_HOOK(PF_BRIDGE, NF_BR_LOCAL_IN, skb, dev, NULL, + batman_skb_recv_finish); + if (ret != 1) + goto err_out; + /* packet should hold at least type and version */ if (unlikely(skb_headlen(skb) < 2)) goto err_free; @@ -531,7 +545,6 @@ err_out: return NET_RX_DROP; }
- struct notifier_block hard_if_notifier = { .notifier_call = hard_if_event, }; diff --git a/batman-adv-kernelland/send.c b/batman-adv-kernelland/send.c index 99d11fe..b0d3627 100644 --- a/batman-adv-kernelland/send.c +++ b/batman-adv-kernelland/send.c @@ -29,6 +29,7 @@ #include "vis.h" #include "aggregation.h" #include "gateway_common.h" +#include <linux/netfilter_bridge.h>
#include "compat.h"
@@ -93,9 +94,12 @@ 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;