can: gw: make routing to the incoming CAN interface configurable
Introduce new configuration flag CGW_FLAGS_CAN_IIF_TX_OK to configure if a
CAN sk_buff that has been routed with can-gw is allowed to be send back to
the originating CAN interface.
Signed-off-by: Oliver Hartkopp <socketcan@hartkopp.net>
Signed-off-by: Marc Kleine-Budde <mkl@pengutronix.de>
diff --git a/net/can/gw.c b/net/can/gw.c
index 574dda78e..37a3efb 100644
--- a/net/can/gw.c
+++ b/net/can/gw.c
@@ -52,6 +52,7 @@
#include <linux/skbuff.h>
#include <linux/can.h>
#include <linux/can/core.h>
+#include <linux/can/skb.h>
#include <linux/can/gw.h>
#include <net/rtnetlink.h>
#include <net/net_namespace.h>
@@ -347,6 +348,13 @@
return;
}
+ /* is sending the skb back to the incoming interface not allowed? */
+ if (!(gwj->flags & CGW_FLAGS_CAN_IIF_TX_OK) &&
+ skb_headroom(skb) == sizeof(struct can_skb_priv) &&
+ (((struct can_skb_priv *)(skb->head))->ifindex ==
+ gwj->dst.dev->ifindex))
+ return;
+
/*
* clone the given skb, which has not been done in can_rcv()
*