diff options
Diffstat (limited to 'pimd/pim_tib.c')
| -rw-r--r-- | pimd/pim_tib.c | 168 |
1 files changed, 168 insertions, 0 deletions
diff --git a/pimd/pim_tib.c b/pimd/pim_tib.c new file mode 100644 index 0000000..4081786 --- /dev/null +++ b/pimd/pim_tib.c @@ -0,0 +1,168 @@ +// SPDX-License-Identifier: GPL-2.0-or-later +/* + * TIB (Tree Information Base) - just PIM <> IGMP/MLD glue for now + * Copyright (C) 2022 David Lamparter for NetDEF, Inc. + */ + +#include <zebra.h> + +#include "pim_tib.h" + +#include "pimd.h" +#include "pim_instance.h" +#include "pim_iface.h" +#include "pim_upstream.h" +#include "pim_oil.h" +#include "pim_nht.h" + +static struct channel_oil * +tib_sg_oil_setup(struct pim_instance *pim, pim_sgaddr sg, struct interface *oif) +{ + struct pim_interface *pim_oif = oif->info; + int input_iface_vif_index = 0; + pim_addr vif_source; + struct prefix grp; + struct pim_nexthop nexthop; + struct pim_upstream *up = NULL; + + if (!pim_rp_set_upstream_addr(pim, &vif_source, sg.src, sg.grp)) { + /* no PIM RP - create a dummy channel oil */ + return pim_channel_oil_add(pim, &sg, __func__); + } + + pim_addr_to_prefix(&grp, sg.grp); + + up = pim_upstream_find(pim, &sg); + if (up) { + memcpy(&nexthop, &up->rpf.source_nexthop, + sizeof(struct pim_nexthop)); + (void)pim_ecmp_nexthop_lookup(pim, &nexthop, vif_source, &grp, + 0); + if (nexthop.interface) + input_iface_vif_index = pim_if_find_vifindex_by_ifindex( + pim, nexthop.interface->ifindex); + } else + input_iface_vif_index = + pim_ecmp_fib_lookup_if_vif_index(pim, vif_source, &grp); + + if (PIM_DEBUG_ZEBRA) + zlog_debug("%s: NHT %pSG vif_source %pPAs vif_index:%d", + __func__, &sg, &vif_source, input_iface_vif_index); + + if (input_iface_vif_index < 1) { + if (PIM_DEBUG_GM_TRACE) + zlog_debug( + "%s %s: could not find input interface for %pSG", + __FILE__, __func__, &sg); + + return pim_channel_oil_add(pim, &sg, __func__); + } + + /* + * Protect IGMP against adding looped MFC entries created by both + * source and receiver attached to the same interface. See TODO T22. + * Block only when the intf is non DR DR must create upstream. + */ + if ((input_iface_vif_index == pim_oif->mroute_vif_index) && + !(PIM_I_am_DR(pim_oif))) { + /* ignore request for looped MFC entry */ + if (PIM_DEBUG_GM_TRACE) + zlog_debug( + "%s: ignoring request for looped MFC entry (S,G)=%pSG: oif=%s vif_index=%d", + __func__, &sg, oif->name, + input_iface_vif_index); + + return NULL; + } + + return pim_channel_oil_add(pim, &sg, __func__); +} + +bool tib_sg_gm_join(struct pim_instance *pim, pim_sgaddr sg, + struct interface *oif, struct channel_oil **oilp) +{ + struct pim_interface *pim_oif = oif->info; + + if (!pim_oif) { + if (PIM_DEBUG_GM_TRACE) + zlog_debug("%s: multicast not enabled on oif=%s?", + __func__, oif->name); + return false; + } + + if (!*oilp) + *oilp = tib_sg_oil_setup(pim, sg, oif); + if (!*oilp) + return false; + + if (PIM_I_am_DR(pim_oif) || PIM_I_am_DualActive(pim_oif)) { + int result; + + result = pim_channel_add_oif(*oilp, oif, PIM_OIF_FLAG_PROTO_GM, + __func__); + if (result) { + if (PIM_DEBUG_MROUTE) + zlog_warn("%s: add_oif() failed with return=%d", + __func__, result); + return false; + } + } else { + if (PIM_DEBUG_GM_TRACE) + zlog_debug( + "%s: %pSG was received on %s interface but we are not DR for that interface", + __func__, &sg, oif->name); + + return false; + } + /* + Feed IGMPv3-gathered local membership information into PIM + per-interface (S,G) state. + */ + if (!pim_ifchannel_local_membership_add(oif, &sg, false /*is_vxlan*/)) { + if (PIM_DEBUG_MROUTE) + zlog_warn( + "%s: Failure to add local membership for %pSG", + __func__, &sg); + + pim_channel_del_oif(*oilp, oif, PIM_OIF_FLAG_PROTO_GM, + __func__); + return false; + } + + return true; +} + +void tib_sg_gm_prune(struct pim_instance *pim, pim_sgaddr sg, + struct interface *oif, struct channel_oil **oilp) +{ + int result; + + /* + It appears that in certain circumstances that + igmp_source_forward_stop is called when IGMP forwarding + was not enabled in oif_flags for this outgoing interface. + Possibly because of multiple calls. When that happens, we + enter the below if statement and this function returns early + which in turn triggers the calling function to assert. + Making the call to pim_channel_del_oif and ignoring the return code + fixes the issue without ill effect, similar to + pim_forward_stop below. + */ + result = pim_channel_del_oif(*oilp, oif, PIM_OIF_FLAG_PROTO_GM, + __func__); + if (result) { + if (PIM_DEBUG_GM_TRACE) + zlog_debug( + "%s: pim_channel_del_oif() failed with return=%d", + __func__, result); + return; + } + + /* + Feed IGMPv3-gathered local membership information into PIM + per-interface (S,G) state. + */ + pim_ifchannel_local_membership_del(oif, &sg); + + pim_channel_oil_del(*oilp, __func__); +} |