On 28 April 2011 07:42, Claudio Jeker <cje...@diehard.n-r-g.com> wrote:
> On Thu, Apr 07, 2011 at 10:47:41AM -0300, Christiano F. Haesbaert wrote:
>> Keeping this up.
>>
>> On 17 March 2011 00:51, Christiano F. Haesbaert <haesba...@haesbaert.org>
>> wrote:
>> > On 12 June 2010 16:26, Christiano F. Haesbaert <haesba...@haesbaert.org>
>> wrote:
>> >> Hi,
>> >>
>> >> The following will disregard the routing table for multicast packets
>> >> when the application chose the interface with IP_MULTICAST_IF, if not,
>> >> normal lookup will take place.
>> >>
>> >> Ripd now no longer needs to explicitly add the mcast host route to
>> >> bypass the default reject to 224/4, follows the diff to remove it.
>> >>
>> >> Regarding the normal lookup when IP_MULTICAST_IF wan't set, UNP
>> >> regards it as a BSD descendant behaviour, I really don't know anything
>> >> else.
>> >>
>> >> I've tested it in a small setup, if someone could confirm it in a
>> >> scarier environment would be nice.
>> >>
>
> What about this version? It moves the multicast source selection before
> the route selection. IMO this is a nicer way to write this instead of
> making an already complex if statement totaly unreadable.
>
> In the end this will help more daemons to run with multicast_host=NO
> when doing multicast. It also matches the behaviour of SOCK_RAW sockets
> since those bypass this code and so don't suffer from the blackhole route
> added by /etc/netstart.
> --
> :wq Claudio
>
> Index: in_pcb.c
> ===================================================================
> RCS file: /cvs/src/sys/netinet/in_pcb.c,v
> retrieving revision 1.119
> diff -u -p -r1.119 in_pcb.c
> --- in_pcb.c 28 Apr 2011 09:56:27 -0000 1.119
> +++ in_pcb.c 28 Apr 2011 10:35:38 -0000
> @@ -824,6 +824,27 @@ in_selectsrc(struct sockaddr_in *sin, st
>
> ia = (struct in_ifaddr *)0;
> /*
> + * If the destination address is multicast and an outgoing
> + * interface has been set as a multicast option, use the
> + * address of that interface as our source address.
> + */
> + if (IN_MULTICAST(sin->sin_addr.s_addr) && mopts != NULL) {
> + struct ifnet *ifp;
> +
> + if (mopts->imo_multicast_ifp != NULL) {
> + ifp = mopts->imo_multicast_ifp;
> + TAILQ_FOREACH(ia, &in_ifaddr, ia_list)
> + if (ia->ia_ifp == ifp &&
> + rtable_l2(rtableid) == ifp->if_rdomain)
> + break;
> + if (ia == 0) {
> + *errorp = EADDRNOTAVAIL;
> + return NULL;
> + }
> + return satosin(&ia->ia_addr);
> + }
> + }
> + /*
> * If route is known or can be allocated now,
> * our src addr is taken from the i/f, else punt.
> */
> @@ -872,27 +893,6 @@ in_selectsrc(struct sockaddr_in *sin, st
> if (ia == 0) {
> *errorp = EADDRNOTAVAIL;
> return NULL;
> - }
> - }
> - /*
> - * If the destination address is multicast and an outgoing
> - * interface has been set as a multicast option, use the
> - * address of that interface as our source address.
> - */
> - if (IN_MULTICAST(sin->sin_addr.s_addr) && mopts != NULL) {
> - struct ip_moptions *imo;
> - struct ifnet *ifp;
> -
> - imo = mopts;
> - if (imo->imo_multicast_ifp != NULL) {
> - ifp = imo->imo_multicast_ifp;
> - TAILQ_FOREACH(ia, &in_ifaddr, ia_list)
> - if (ia->ia_ifp == ifp)
> - break;
> - if (ia == 0) {
> - *errorp = EADDRNOTAVAIL;
> - return NULL;
> - }
> }
> }
> return satosin(&ia->ia_addr);
>
Oh yeah, much nicer :D, I'll test it and report back.
