can-gw: add netlink based CAN routing

This patch adds a CAN Gateway/Router to route (and modify) CAN frames.

It is based on the PF_CAN core infrastructure for msg filtering and msg
sending and can optionally modify routed CAN frames on the fly.
CAN frames can *only* be routed between CAN network interfaces (one hop).
They can be modified with AND/OR/XOR/SET operations as configured by the
netlink configuration interface known e.g. from iptables. From the netlink
view this can-gw implements RTM_{NEW|DEL|GET}ROUTE for PF_CAN.

The CAN specific userspace tool to manage CAN routing entries can be found in
the CAN utils http://svn.berlios.de/wsvn/socketcan/trunk/can-utils/cangw.c
at the SocketCAN SVN on BerliOS.

Signed-off-by: Oliver Hartkopp <socketcan@hartkopp.net>
Signed-off-by: David S. Miller <davem@davemloft.net>

1 files changed, 11 insertions, 0 deletions

diff --git a/net/can/Kconfig b/net/can/Kconfig
index 89395b2c8bca..03200699d274 100644
--- a/net/can/Kconfig
+++ b/net/can/Kconfig
@@ -40,5 +40,16 @@ config CAN_BCM
           CAN messages are used on the bus (e.g. in automotive environments).
           To use the Broadcast Manager, use AF_CAN with protocol CAN_BCM.
 
+config CAN_GW
+        tristate "CAN Gateway/Router (with netlink configuration)"
+        depends on CAN
+        default N
+        ---help---
+          The CAN Gateway/Router is used to route (and modify) CAN frames.
+          It is based on the PF_CAN core infrastructure for msg filtering and
+          msg sending and can optionally modify routed CAN frames on the fly.
+          CAN frames can be routed between CAN network interfaces (one hop).
+          They can be modified with AND/OR/XOR/SET operations as configured
+          by the netlink configuration interface known e.g. from iptables.
 
 source "drivers/net/can/Kconfig"