On Tue, Mar 25, 2014 at 11:39:30AM +0100, Martin Pieuchot wrote:
> Why do we do a lookup on all the addresses of the systems to know if the
> destination address given to ether_output() is on the carp interface?
>
> If this address is on any of our interfaces we should not even end up
> here. Since both arp_rtrequest() and nd6_rtrequest() change the ifp
> of the route entries for our addresses to loopback, if `dst' is one
> of our addresses it won't be passed to ether_output() but looutput().
>
> ok?
I think this is OK and the check should die in a fire but...
What about bpf senders or more exotic things like MPLS?
I think ifa_ifwithaddr() will fail on them but I learned that some of
those checks are non obivous but needed.
> Index: net/if_ethersubr.c
> ===================================================================
> RCS file: /home/ncvs/src/sys/net/if_ethersubr.c,v
> retrieving revision 1.162
> diff -u -p -r1.162 if_ethersubr.c
> --- net/if_ethersubr.c 17 Feb 2014 14:48:48 -0000 1.162
> +++ net/if_ethersubr.c 24 Mar 2014 15:35:53 -0000
> @@ -226,27 +226,16 @@ ether_output(struct ifnet *ifp0, struct
> senderr(EBUSY);
> #endif
>
> + if ((ifp->if_flags & (IFF_UP|IFF_RUNNING)) != (IFF_UP|IFF_RUNNING))
> + senderr(ENETDOWN);
> +
> #if NCARP > 0
> if (ifp->if_type == IFT_CARP) {
> - struct ifaddr *ifa;
> -
> - /* loop back if this is going to the carp interface */
> - if (dst != NULL && LINK_STATE_IS_UP(ifp0->if_link_state) &&
> - (ifa = ifa_ifwithaddr(dst, ifp->if_rdomain)) != NULL &&
> - ifa->ifa_ifp == ifp0)
> - return (looutput(ifp0, m, dst, rt0));
> -
> ifp = ifp->if_carpdev;
> ac = (struct arpcom *)ifp;
> -
> - if ((ifp0->if_flags & (IFF_UP|IFF_RUNNING)) !=
> - (IFF_UP|IFF_RUNNING))
> - senderr(ENETDOWN);
> }
> #endif /* NCARP > 0 */
>
> - if ((ifp->if_flags & (IFF_UP|IFF_RUNNING)) != (IFF_UP|IFF_RUNNING))
> - senderr(ENETDOWN);
> if ((rt = rt0) != NULL) {
> if ((rt->rt_flags & RTF_UP) == 0) {
> if ((rt0 = rt = rtalloc1(dst, RT_REPORT,
>
--
:wq Claudio
