Re: [PATCH net-next] bridge: multicast to unicast
From: Linus LÃssing
Date: Mon Jan 09 2017 - 07:43:11 EST
On Mon, Jan 09, 2017 at 09:05:49AM +0100, Johannes Berg wrote:
> On Sat, 2017-01-07 at 16:15 +0100, Linus LÃssing wrote:
>
> > Actually, I do not quite understand that remark in the mac80211
> > multicast-to-unicast patch. IP should not care about the ethernet
> > header?
>
> But it does, for example RFC 1122 states:
>
> ÂÂÂÂÂÂÂÂÂWhen a host sends a datagram to a link-layer broadcast address,
> ÂÂÂÂÂÂÂÂÂthe IP destination address MUST be a legal IP broadcast or IP
> ÂÂÂÂÂÂÂÂÂmulticast address.
>
> ÂÂÂÂÂÂÂÂA host SHOULD silently discard a datagram that is received via
> ÂÂÂÂÂÂÂÂÂa link-layer broadcast (see Section 2.4) but does not specify
> ÂÂÂÂÂÂÂÂÂan IP multicast or broadcast destination address.
This example is the other way round. It specifies how the IP
destination should look like in case of link-layer broadcast. Not
how the link-layer destination should look like in case of a
multicast/broadcast IP destination.
Any other examples?