diff options
Diffstat (limited to 'pimd/pim_upstream.c')
| -rw-r--r-- | pimd/pim_upstream.c | 101 |
1 files changed, 78 insertions, 23 deletions
diff --git a/pimd/pim_upstream.c b/pimd/pim_upstream.c index fdb7363042..e9382be33f 100644 --- a/pimd/pim_upstream.c +++ b/pimd/pim_upstream.c @@ -561,6 +561,63 @@ void pim_upstream_register_reevaluate(struct pim_instance *pim) } } +/* RFC7761, Section 4.2 “Data Packet Forwarding Rules” says we should + * forward a S - + * 1. along the SPT if SPTbit is set + * 2. and along the RPT if SPTbit is not set + * If forwarding is hw accelerated i.e. control and dataplane components + * are separate you may not be able to reliably set SPT bit on intermediate + * routers while still fowarding on the (S,G,rpt). + * + * This macro is a slight deviation on the RFC and uses "traffic-agnostic" + * criteria to decide between using the RPT vs. SPT for forwarding. + */ +void pim_upstream_update_use_rpt(struct pim_upstream *up, + bool update_mroute) +{ + bool old_use_rpt; + bool new_use_rpt; + + if (up->sg.src.s_addr == INADDR_ANY) + return; + + old_use_rpt = !!PIM_UPSTREAM_FLAG_TEST_USE_RPT(up->flags); + + /* We will use the SPT (IIF=RPF_interface(S) if - + * 1. We have decided to join the SPT + * 2. We are FHR + * 3. Source is directly connected + * 4. We are RP (parent's IIF is lo or vrf-device) + * In all other cases the source will stay along the RPT and + * IIF=RPF_interface(RP). + */ + if (up->join_state == PIM_UPSTREAM_JOINED || + PIM_UPSTREAM_FLAG_TEST_FHR(up->flags) || + pim_if_connected_to_source( + up->rpf.source_nexthop.interface, + up->sg.src) || + /* XXX - need to switch this to a more efficient + * lookup API + */ + I_am_RP(up->pim, up->sg.grp)) + /* use SPT */ + PIM_UPSTREAM_FLAG_UNSET_USE_RPT(up->flags); + else + /* use RPT */ + PIM_UPSTREAM_FLAG_SET_USE_RPT(up->flags); + + new_use_rpt = !!PIM_UPSTREAM_FLAG_TEST_USE_RPT(up->flags); + if (old_use_rpt != new_use_rpt) { + if (PIM_DEBUG_PIM_EVENTS) + zlog_debug("%s switched from %s to %s", + up->sg_str, + old_use_rpt?"RPT":"SPT", + new_use_rpt?"RPT":"SPT"); + if (update_mroute) + pim_upstream_mroute_add(up->channel_oil, __func__); + } +} + void pim_upstream_switch(struct pim_instance *pim, struct pim_upstream *up, enum pim_upstream_state new_state) { @@ -642,6 +699,9 @@ void pim_upstream_switch(struct pim_instance *pim, struct pim_upstream *up, 0 /* prune */); join_timer_stop(up); } + + if (old_state != new_state) + pim_upstream_update_use_rpt(up, true /*update_mroute*/); } int pim_upstream_compare(void *arg1, void *arg2) @@ -693,6 +753,7 @@ static struct pim_upstream *pim_upstream_new(struct pim_instance *pim, up = XCALLOC(MTYPE_PIM_UPSTREAM, sizeof(*up)); + up->pim = pim; up->sg = *sg; pim_str_sg_set(sg, up->sg_str); if (ch) @@ -776,6 +837,8 @@ static struct pim_upstream *pim_upstream_new(struct pim_instance *pim, pim_ifp->mroute_vif_index, __PRETTY_FUNCTION__); } + pim_upstream_update_use_rpt(up, + false /*update_mroute*/); } listnode_add_sort(pim->upstream_list, up); @@ -802,35 +865,26 @@ struct pim_upstream *pim_upstream_find(struct pim_instance *pim, } struct pim_upstream *pim_upstream_find_or_add(struct prefix_sg *sg, - struct interface *incoming, - int flags, const char *name) + struct interface *incoming, + int flags, const char *name) { - struct pim_upstream *up; - struct pim_interface *pim_ifp; - - pim_ifp = incoming->info; - - up = pim_upstream_find(pim_ifp->pim, sg); + struct pim_interface *pim_ifp = incoming->info; - if (up) { - if (!(up->flags & flags)) { - up->flags |= flags; - up->ref_count++; - if (PIM_DEBUG_PIM_TRACE) - zlog_debug( - "%s(%s): upstream %s ref count %d increment", - __PRETTY_FUNCTION__, name, up->sg_str, - up->ref_count); - } - } else - up = pim_upstream_add(pim_ifp->pim, sg, incoming, flags, name, - NULL); - - return up; + return (pim_upstream_add(pim_ifp->pim, sg, incoming, flags, name, + NULL)); } void pim_upstream_ref(struct pim_upstream *up, int flags, const char *name) { + /* when we go from non-FHR to FHR we need to re-eval traffic + * forwarding path + */ + if (!PIM_UPSTREAM_FLAG_TEST_FHR(up->flags) && + PIM_UPSTREAM_FLAG_TEST_FHR(flags)) { + PIM_UPSTREAM_FLAG_SET_FHR(up->flags); + pim_upstream_update_use_rpt(up, true /*update_mroute*/); + } + up->flags |= flags; ++up->ref_count; if (PIM_DEBUG_PIM_TRACE) @@ -1146,6 +1200,7 @@ static void pim_upstream_fhr_kat_start(struct pim_upstream *up) PIM_UPSTREAM_FLAG_SET_FHR(up->flags); if (up->reg_state == PIM_REG_NOINFO) pim_register_join(up); + pim_upstream_update_use_rpt(up, true /*update_mroute*/); } } |