How can I redirect/forward all the UDP/TCP traffic on one interface to another interface in OpenWrt

Posted by Sina Sou on Server Fault See other posts from Server Fault or by Sina Sou
Published on 2013-10-26T14:55:24Z Indexed on 2013/10/26 15:56 UTC
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I am new to networking and I have a measurement device (D) that periodically sends all its readings over few UDP multicast sockets (with different multicast IP addresses and different port numbers).

That device even listens to a TCP socket simultaneously to modify its configuration on port 7234.

Since the device has just a Ethernet interface for communication and I want to make it work wireless, I decided to use a very small wireless open-wrt based router that attaches to the device (D) and redirect/forward all the network traffic(Both UDP/TCP) to the router wireless interface.

In order to simplify the problem assume that the Device (D) establishes following sockets (at the same time)

UM_SOCK1: UDP mcast socket on 239.1.2.3 port# 50620 UM_SOCK2: UDP mcast socket on 239.1.2.4 port# 50640 TC_SOCK3: TCP DHCP/STATIC ip address 192.168.1.200 port 7234

And (D) is connected to Open-Wrt router (R) via interface en01 (Ethernet) the router has it own wireless interface on (wlan0)

I want all the traffic from interface pass through wlan01 and vice versa (bi-directional) en01 <----> wlan01

What would be the minimum iptables or ... commands that I need to make this possible?

Even I am wondering if traffic directing can be made easier like if the direction is not going to be based on IP addresses(not desired if the device is connected via DHCP)

I would rather redirection to be Interface(en0) based or on MAC address (The best solution since my device has unique MAC address)?

Thanks

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