Merge pull request #10940 from opensourcerouting/pim-5549-clarify

pimd: clarify RFC5549 nexthop handling (& fix for pim6d)
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Donald Sharp 2022-04-05 09:43:39 -04:00 committed by GitHub
commit 0e3aad23de
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@ -696,9 +696,7 @@ int pim_parse_nexthop_update(ZAPI_CALLBACK_ARGS)
int i;
struct pim_rpf rpf;
struct pim_nexthop_cache *pnc = NULL;
struct pim_neighbor *nbr = NULL;
struct interface *ifp = NULL;
struct interface *ifp1 = NULL;
struct vrf *vrf = vrf_lookup_by_id(vrf_id);
struct pim_instance *pim;
struct zapi_route nhr;
@ -739,11 +737,6 @@ int pim_parse_nexthop_update(ZAPI_CALLBACK_ARGS)
for (i = 0; i < nhr.nexthop_num; i++) {
nexthop = nexthop_from_zapi_nexthop(&nhr.nexthops[i]);
switch (nexthop->type) {
case NEXTHOP_TYPE_IPV4:
case NEXTHOP_TYPE_IPV4_IFINDEX:
case NEXTHOP_TYPE_IPV6:
case NEXTHOP_TYPE_BLACKHOLE:
break;
case NEXTHOP_TYPE_IFINDEX:
/*
* Connected route (i.e. no nexthop), use
@ -760,33 +753,46 @@ int pim_parse_nexthop_update(ZAPI_CALLBACK_ARGS)
pnc->rpf.rpf_addr.u.prefix6;
#endif
break;
case NEXTHOP_TYPE_IPV6_IFINDEX:
#if PIM_IPV == 4
/* RFC5549 IPv4-over-IPv6 nexthop handling:
* if we get an IPv6 nexthop in IPv4 PIM, hunt down a
* PIM neighbor and use that instead.
*/
case NEXTHOP_TYPE_IPV6_IFINDEX: {
struct interface *ifp1 = NULL;
struct pim_neighbor *nbr = NULL;
ifp1 = if_lookup_by_index(nexthop->ifindex,
pim->vrf->vrf_id);
if (!ifp1)
nbr = NULL;
else
/* FIXME: should really use nbr's
* secondary address list here
*/
nbr = pim_neighbor_find_if(ifp1);
/* Overwrite with Nbr address as NH addr */
if (nbr)
#if PIM_IPV == 4
nexthop->gate.ipv4 = nbr->source_addr;
#else
nexthop->gate.ipv6 = nbr->source_addr;
#endif
else {
else
// Mark nexthop address to 0 until PIM
// Nbr is resolved.
#if PIM_IPV == 4
nexthop->gate.ipv4 = PIMADDR_ANY;
#else
nexthop->gate.ipv6 = PIMADDR_ANY;
#endif
}
break;
}
#else
case NEXTHOP_TYPE_IPV6_IFINDEX:
#endif
case NEXTHOP_TYPE_IPV6:
case NEXTHOP_TYPE_IPV4:
case NEXTHOP_TYPE_IPV4_IFINDEX:
case NEXTHOP_TYPE_BLACKHOLE:
/* nothing to do for the other nexthop types */
break;
}
ifp = if_lookup_by_index(nexthop->ifindex,
pim->vrf->vrf_id);
@ -804,13 +810,18 @@ int pim_parse_nexthop_update(ZAPI_CALLBACK_ARGS)
continue;
}
if (PIM_DEBUG_PIM_NHT)
if (PIM_DEBUG_PIM_NHT) {
#if PIM_IPV == 4
pim_addr nhaddr = nexthop->gate.ipv4;
#else
pim_addr nhaddr = nexthop->gate.ipv6;
#endif
zlog_debug(
"%s: NHT addr %pFX(%s) %d-nhop via %pI4(%s) type %d distance:%u metric:%u ",
"%s: NHT addr %pFX(%s) %d-nhop via %pPA(%s) type %d distance:%u metric:%u ",
__func__, &match, pim->vrf->name, i + 1,
&nexthop->gate.ipv4, ifp->name,
nexthop->type, nhr.distance,
nhr.metric);
&nhaddr, ifp->name, nexthop->type,
nhr.distance, nhr.metric);
}
if (!ifp->info) {
/*