Re: protocol handler for a proprietary protocol

Chris Friesen wrote:
Tauno Voipio wrote:

The tun/tap driver is in reverse to what the OP wants to do.
The tun/tap creates a pseudo-interface to connect to the network
stack toward the internals of the host, but the OP wants to
connect to the link level interface (Ethernet). The packet
socket is the correct method here.


If you set up ethernet bridging you can forward the packets injected via tun/tap out a real ethernet device.

<nitpicking>

Sending network layer packets to another host is forwarding,
sending data link layer packets directly to another interface is
bridging.

</nitpicking>

The bridging is set up so that there will be a new pseudo-interface,
the bridge, named from br0 onward. The IP properties are set to the
bridge interface, and the IP packets are handled like the packets
to / from a real data link interface. The data-link frames are
'forwarded' between the members of the bridge without ever visiting
the IP layer. An important detail is that the bridge component
interfaces shall not have IP addresses or routings of their own
anymore. This applies to the bridged tap interface as well.

The bridge interface is included into the normal routing tables
of the IP layer as any other data link interface, and the packets
can be forwarded to an interface not in the same bridge (and back,
of course).

--

Tauno Voipio
tauno voipio (at) iki fi
.

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