Johannes Berg
2017-Jan-09 08:05 UTC
[Bridge] [PATCH net-next] bridge: multicast to unicast
On Sat, 2017-01-07 at 16:15 +0100, Linus L?ssing 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: ?????????When a host sends a datagram to a link-layer broadcast address, ?????????the IP destination address MUST be a legal IP broadcast or IP ?????????multicast address. ????????A host SHOULD silently discard a datagram that is received via ?????????a link-layer broadcast (see Section 2.4) but does not specify ?????????an IP multicast or broadcast destination address. You can probably find other examples too. johannes
Linus Lüssing
2017-Jan-09 12:42 UTC
[Bridge] [PATCH net-next] bridge: multicast to unicast
On Mon, Jan 09, 2017 at 09:05:49AM +0100, Johannes Berg wrote:> On Sat, 2017-01-07 at 16:15 +0100, Linus L?ssing 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: > > ?????????When a host sends a datagram to a link-layer broadcast address, > ?????????the IP destination address MUST be a legal IP broadcast or IP > ?????????multicast address. > > ????????A host SHOULD silently discard a datagram that is received via > ?????????a link-layer broadcast (see Section 2.4) but does not specify > ?????????an 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?