itojun@iijlab.net writes:

> 	sys/net/if_ethersubr.c has IFF_SIMPLEX checks for broadcast cases
> 	(M_BCAST) and not for multicast (M_MCAST).  are there specific
> 	reasons for this?   if multicast handling was introduced after
> 	IFF_SIMPLEX is invented, it may be a bug in L2 multicast support.

Unless explicitly disabled, multicast packets are looped back in L3,
aren't they?

enami.