/** * bgp_updgrp_adv.c: BGP update group advertisement and adjacency * maintenance * * * @copyright Copyright (C) 2014 Cumulus Networks, Inc. * * @author Avneesh Sachdev * @author Rajesh Varadarajan * @author Pradosh Mohapatra * * This file is part of GNU Zebra. * * GNU Zebra is free software; you can redistribute it and/or modify it * under the terms of the GNU General Public License as published by the * Free Software Foundation; either version 2, or (at your option) any * later version. * * GNU Zebra is distributed in the hope that it will be useful, but * WITHOUT ANY WARRANTY; without even the implied warranty of * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU * General Public License for more details. * * You should have received a copy of the GNU General Public License along * with this program; see the file COPYING; if not, write to the Free Software * Foundation, Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA */ #include #include "command.h" #include "memory.h" #include "prefix.h" #include "hash.h" #include "thread.h" #include "queue.h" #include "routemap.h" #include "filter.h" #include "bgpd/bgpd.h" #include "bgpd/bgp_table.h" #include "bgpd/bgp_debug.h" #include "bgpd/bgp_route.h" #include "bgpd/bgp_advertise.h" #include "bgpd/bgp_attr.h" #include "bgpd/bgp_aspath.h" #include "bgpd/bgp_packet.h" #include "bgpd/bgp_fsm.h" #include "bgpd/bgp_mplsvpn.h" #include "bgpd/bgp_updgrp.h" #include "bgpd/bgp_advertise.h" #include "bgpd/bgp_addpath.h" /******************** * PRIVATE FUNCTIONS ********************/ static int bgp_adj_out_compare(const struct bgp_adj_out *o1, const struct bgp_adj_out *o2) { if (o1->subgroup < o2->subgroup) return -1; if (o1->subgroup > o2->subgroup) return 1; if (o1->addpath_tx_id < o2->addpath_tx_id) return -1; if (o1->addpath_tx_id > o2->addpath_tx_id) return 1; return 0; } RB_GENERATE(bgp_adj_out_rb, bgp_adj_out, adj_entry, bgp_adj_out_compare); static inline struct bgp_adj_out *adj_lookup(struct bgp_dest *dest, struct update_subgroup *subgrp, uint32_t addpath_tx_id) { struct bgp_adj_out lookup; if (!dest || !subgrp) return NULL; /* update-groups that do not support addpath will pass 0 for * addpath_tx_id. */ lookup.subgroup = subgrp; lookup.addpath_tx_id = addpath_tx_id; return RB_FIND(bgp_adj_out_rb, &dest->adj_out, &lookup); } static void adj_free(struct bgp_adj_out *adj) { TAILQ_REMOVE(&(adj->subgroup->adjq), adj, subgrp_adj_train); SUBGRP_DECR_STAT(adj->subgroup, adj_count); RB_REMOVE(bgp_adj_out_rb, &adj->dest->adj_out, adj); bgp_dest_unlock_node(adj->dest); XFREE(MTYPE_BGP_ADJ_OUT, adj); } static void subgrp_withdraw_stale_addpath(struct updwalk_context *ctx, struct update_subgroup *subgrp) { struct bgp_adj_out *adj, *adj_next; uint32_t id; struct bgp_path_info *pi; afi_t afi = SUBGRP_AFI(subgrp); safi_t safi = SUBGRP_SAFI(subgrp); struct peer *peer = SUBGRP_PEER(subgrp); /* Look through all of the paths we have advertised for this rn and send * a withdraw for the ones that are no longer present */ RB_FOREACH_SAFE (adj, bgp_adj_out_rb, &ctx->dest->adj_out, adj_next) { if (adj->subgroup != subgrp) continue; for (pi = bgp_dest_get_bgp_path_info(ctx->dest); pi; pi = pi->next) { id = bgp_addpath_id_for_peer(peer, afi, safi, &pi->tx_addpath); if (id == adj->addpath_tx_id) { break; } } if (!pi) { subgroup_process_announce_selected( subgrp, NULL, ctx->dest, adj->addpath_tx_id); } } } static int group_announce_route_walkcb(struct update_group *updgrp, void *arg) { struct updwalk_context *ctx = arg; struct update_subgroup *subgrp; struct bgp_path_info *pi; afi_t afi; safi_t safi; struct peer *peer; struct bgp_adj_out *adj, *adj_next; bool addpath_capable; afi = UPDGRP_AFI(updgrp); safi = UPDGRP_SAFI(updgrp); peer = UPDGRP_PEER(updgrp); addpath_capable = bgp_addpath_encode_tx(peer, afi, safi); if (BGP_DEBUG(update, UPDATE_OUT)) zlog_debug("%s: afi=%s, safi=%s, p=%pRN", __func__, afi2str(afi), safi2str(safi), bgp_dest_to_rnode(ctx->dest)); UPDGRP_FOREACH_SUBGRP (updgrp, subgrp) { /* * Skip the subgroups that have coalesce timer running. We will * walk the entire prefix table for those subgroups when the * coalesce timer fires. */ if (!subgrp->t_coalesce) { /* An update-group that uses addpath */ if (addpath_capable) { subgrp_withdraw_stale_addpath(ctx, subgrp); for (pi = bgp_dest_get_bgp_path_info(ctx->dest); pi; pi = pi->next) { /* Skip the bestpath for now */ if (pi == ctx->pi) continue; subgroup_process_announce_selected( subgrp, pi, ctx->dest, bgp_addpath_id_for_peer( peer, afi, safi, &pi->tx_addpath)); } /* Process the bestpath last so the "show [ip] * bgp neighbor x.x.x.x advertised" * output shows the attributes from the bestpath */ if (ctx->pi) subgroup_process_announce_selected( subgrp, ctx->pi, ctx->dest, bgp_addpath_id_for_peer( peer, afi, safi, &ctx->pi->tx_addpath)); } /* An update-group that does not use addpath */ else { if (ctx->pi) { subgroup_process_announce_selected( subgrp, ctx->pi, ctx->dest, bgp_addpath_id_for_peer( peer, afi, safi, &ctx->pi->tx_addpath)); } else { /* Find the addpath_tx_id of the path we * had advertised and * send a withdraw */ RB_FOREACH_SAFE (adj, bgp_adj_out_rb, &ctx->dest->adj_out, adj_next) { if (adj->subgroup == subgrp) { subgroup_process_announce_selected( subgrp, NULL, ctx->dest, adj->addpath_tx_id); } } } } } /* Notify BGP Conditional advertisement */ bgp_notify_conditional_adv_scanner(subgrp); } return UPDWALK_CONTINUE; } static void subgrp_show_adjq_vty(struct update_subgroup *subgrp, struct vty *vty, uint8_t flags) { struct bgp_table *table; struct bgp_adj_out *adj; unsigned long output_count; struct bgp_dest *dest; int header1 = 1; struct bgp *bgp; int header2 = 1; bgp = SUBGRP_INST(subgrp); if (!bgp) return; table = bgp->rib[SUBGRP_AFI(subgrp)][SUBGRP_SAFI(subgrp)]; output_count = 0; for (dest = bgp_table_top(table); dest; dest = bgp_route_next(dest)) { const struct prefix *dest_p = bgp_dest_get_prefix(dest); RB_FOREACH (adj, bgp_adj_out_rb, &dest->adj_out) { if (adj->subgroup != subgrp) continue; if (header1) { vty_out(vty, "BGP table version is %" PRIu64 ", local router ID is %pI4\n", table->version, &bgp->router_id); vty_out(vty, BGP_SHOW_SCODE_HEADER); vty_out(vty, BGP_SHOW_OCODE_HEADER); header1 = 0; } if (header2) { vty_out(vty, BGP_SHOW_HEADER); header2 = 0; } if ((flags & UPDWALK_FLAGS_ADVQUEUE) && adj->adv && adj->adv->baa) { route_vty_out_tmp( vty, dest, dest_p, adj->adv->baa->attr, SUBGRP_SAFI(subgrp), 0, NULL, false); output_count++; } if ((flags & UPDWALK_FLAGS_ADVERTISED) && adj->attr) { route_vty_out_tmp(vty, dest, dest_p, adj->attr, SUBGRP_SAFI(subgrp), 0, NULL, false); output_count++; } } } if (output_count != 0) vty_out(vty, "\nTotal number of prefixes %ld\n", output_count); } static int updgrp_show_adj_walkcb(struct update_group *updgrp, void *arg) { struct updwalk_context *ctx = arg; struct update_subgroup *subgrp; struct vty *vty; vty = ctx->vty; UPDGRP_FOREACH_SUBGRP (updgrp, subgrp) { if (ctx->subgrp_id && (ctx->subgrp_id != subgrp->id)) continue; vty_out(vty, "update group %" PRIu64 ", subgroup %" PRIu64 "\n", updgrp->id, subgrp->id); subgrp_show_adjq_vty(subgrp, vty, ctx->flags); } return UPDWALK_CONTINUE; } static void updgrp_show_adj(struct bgp *bgp, afi_t afi, safi_t safi, struct vty *vty, uint64_t id, uint8_t flags) { struct updwalk_context ctx; memset(&ctx, 0, sizeof(ctx)); ctx.vty = vty; ctx.subgrp_id = id; ctx.flags = flags; update_group_af_walk(bgp, afi, safi, updgrp_show_adj_walkcb, &ctx); } static void subgroup_coalesce_timer(struct thread *thread) { struct update_subgroup *subgrp; struct bgp *bgp; subgrp = THREAD_ARG(thread); if (bgp_debug_update(NULL, NULL, subgrp->update_group, 0)) zlog_debug("u%" PRIu64 ":s%" PRIu64" announcing routes upon coalesce timer expiry(%u ms)", (SUBGRP_UPDGRP(subgrp))->id, subgrp->id, subgrp->v_coalesce); subgrp->t_coalesce = NULL; subgrp->v_coalesce = 0; bgp = SUBGRP_INST(subgrp); subgroup_announce_route(subgrp); /* While the announce_route() may kick off the route advertisement timer * for * the members of the subgroup, we'd like to send the initial updates * much * faster (i.e., without enforcing MRAI). Also, if there were no routes * to * announce, this is the method currently employed to trigger the EOR. */ if (!bgp_update_delay_active(SUBGRP_INST(subgrp)) && !(BGP_SUPPRESS_FIB_ENABLED(bgp))) { struct peer_af *paf; struct peer *peer; SUBGRP_FOREACH_PEER (subgrp, paf) { peer = PAF_PEER(paf); THREAD_OFF(peer->t_routeadv); BGP_TIMER_ON(peer->t_routeadv, bgp_routeadv_timer, 0); } } } static int update_group_announce_walkcb(struct update_group *updgrp, void *arg) { struct update_subgroup *subgrp; UPDGRP_FOREACH_SUBGRP (updgrp, subgrp) { subgroup_announce_all(subgrp); } return UPDWALK_CONTINUE; } static int update_group_announce_rrc_walkcb(struct update_group *updgrp, void *arg) { struct update_subgroup *subgrp; afi_t afi; safi_t safi; struct peer *peer; afi = UPDGRP_AFI(updgrp); safi = UPDGRP_SAFI(updgrp); peer = UPDGRP_PEER(updgrp); /* Only announce if this is a group of route-reflector-clients */ if (CHECK_FLAG(peer->af_flags[afi][safi], PEER_FLAG_REFLECTOR_CLIENT)) { UPDGRP_FOREACH_SUBGRP (updgrp, subgrp) { subgroup_announce_all(subgrp); } } return UPDWALK_CONTINUE; } /******************** * PUBLIC FUNCTIONS ********************/ /** * Allocate an adj-out object. Do proper initialization of its fields, * primarily its association with the subgroup and the prefix. */ struct bgp_adj_out *bgp_adj_out_alloc(struct update_subgroup *subgrp, struct bgp_dest *dest, uint32_t addpath_tx_id) { struct bgp_adj_out *adj; adj = XCALLOC(MTYPE_BGP_ADJ_OUT, sizeof(struct bgp_adj_out)); adj->subgroup = subgrp; adj->addpath_tx_id = addpath_tx_id; RB_INSERT(bgp_adj_out_rb, &dest->adj_out, adj); bgp_dest_lock_node(dest); adj->dest = dest; TAILQ_INSERT_TAIL(&(subgrp->adjq), adj, subgrp_adj_train); SUBGRP_INCR_STAT(subgrp, adj_count); return adj; } struct bgp_advertise * bgp_advertise_clean_subgroup(struct update_subgroup *subgrp, struct bgp_adj_out *adj) { struct bgp_advertise *adv; struct bgp_advertise_attr *baa; struct bgp_advertise *next; struct bgp_adv_fifo_head *fhead; adv = adj->adv; baa = adv->baa; next = NULL; if (baa) { fhead = &subgrp->sync->update; /* Unlink myself from advertise attribute FIFO. */ bgp_advertise_delete(baa, adv); /* Fetch next advertise candidate. */ next = baa->adv; /* Unintern BGP advertise attribute. */ bgp_advertise_attr_unintern(subgrp->hash, baa); } else fhead = &subgrp->sync->withdraw; /* Unlink myself from advertisement FIFO. */ bgp_adv_fifo_del(fhead, adv); /* Free memory. */ bgp_advertise_free(adj->adv); adj->adv = NULL; return next; } void bgp_adj_out_set_subgroup(struct bgp_dest *dest, struct update_subgroup *subgrp, struct attr *attr, struct bgp_path_info *path) { struct bgp_adj_out *adj = NULL; struct bgp_advertise *adv; struct peer *peer; afi_t afi; safi_t safi; struct peer *adv_peer; struct peer_af *paf; struct bgp *bgp; uint32_t attr_hash = attrhash_key_make(attr); peer = SUBGRP_PEER(subgrp); afi = SUBGRP_AFI(subgrp); safi = SUBGRP_SAFI(subgrp); bgp = SUBGRP_INST(subgrp); if (DISABLE_BGP_ANNOUNCE) return; /* Look for adjacency information. */ adj = adj_lookup( dest, subgrp, bgp_addpath_id_for_peer(peer, afi, safi, &path->tx_addpath)); if (adj) { if (CHECK_FLAG(subgrp->sflags, SUBGRP_STATUS_TABLE_REPARSING)) subgrp->pscount++; } else { adj = bgp_adj_out_alloc( subgrp, dest, bgp_addpath_id_for_peer(peer, afi, safi, &path->tx_addpath)); if (!adj) return; subgrp->pscount++; } /* Check if we are sending the same route. This is needed to * avoid duplicate UPDATES. For instance, filtering communities * at egress, neighbors will see duplicate UPDATES despite * the route wasn't changed actually. * Do not suppress BGP UPDATES for route-refresh. */ if (CHECK_FLAG(bgp->flags, BGP_FLAG_SUPPRESS_DUPLICATES) && !CHECK_FLAG(subgrp->sflags, SUBGRP_STATUS_FORCE_UPDATES) && adj->attr_hash == attr_hash) { if (BGP_DEBUG(update, UPDATE_OUT)) { char attr_str[BUFSIZ] = {0}; bgp_dump_attr(attr, attr_str, sizeof(attr_str)); zlog_debug("%s suppress UPDATE w/ attr: %s", peer->host, attr_str); } /* * If BGP is skipping sending this value to it's peers * the version number should be updated just like it * would if it sent the data. Why? Because update * groups will not be coalesced until such time that * the version numbers are the same. * * Imagine a scenario with say 2 peers and they come * up and are placed in the same update group. Then * a new peer comes up a bit later. Then a prefix is * flapped that we decide for the first 2 peers are * mapped to and we decide not to send the data to * it. Then unless more network changes happen we * will never be able to coalesce the 3rd peer down */ subgrp->version = MAX(subgrp->version, dest->version); return; } if (adj->adv) bgp_advertise_clean_subgroup(subgrp, adj); adj->adv = bgp_advertise_new(); adv = adj->adv; adv->dest = dest; assert(adv->pathi == NULL); /* bgp_path_info adj_out reference */ adv->pathi = bgp_path_info_lock(path); adv->baa = bgp_advertise_attr_intern(subgrp->hash, attr); adv->adj = adj; adj->attr_hash = attr_hash; /* Add new advertisement to advertisement attribute list. */ bgp_advertise_add(adv->baa, adv); /* * If the update adv list is empty, trigger the member peers' * mrai timers so the socket writes can happen. */ if (!bgp_adv_fifo_count(&subgrp->sync->update)) { SUBGRP_FOREACH_PEER (subgrp, paf) { /* If there are no routes in the withdraw list, set * the flag PEER_STATUS_ADV_DELAY which will allow * more routes to be sent in the update message */ if (BGP_SUPPRESS_FIB_ENABLED(bgp)) { adv_peer = PAF_PEER(paf); if (!bgp_adv_fifo_count( &subgrp->sync->withdraw)) SET_FLAG(adv_peer->thread_flags, PEER_THREAD_SUBGRP_ADV_DELAY); else UNSET_FLAG(adv_peer->thread_flags, PEER_THREAD_SUBGRP_ADV_DELAY); } bgp_adjust_routeadv(PAF_PEER(paf)); } } bgp_adv_fifo_add_tail(&subgrp->sync->update, adv); subgrp->version = MAX(subgrp->version, dest->version); } /* The only time 'withdraw' will be false is if we are sending * the "neighbor x.x.x.x default-originate" default and need to clear * bgp_adj_out for the 0.0.0.0/0 route in the BGP table. */ void bgp_adj_out_unset_subgroup(struct bgp_dest *dest, struct update_subgroup *subgrp, char withdraw, uint32_t addpath_tx_id) { struct bgp_adj_out *adj; struct bgp_advertise *adv; bool trigger_write; if (DISABLE_BGP_ANNOUNCE) return; /* Lookup existing adjacency */ adj = adj_lookup(dest, subgrp, addpath_tx_id); if (adj != NULL) { /* Clean up previous advertisement. */ if (adj->adv) bgp_advertise_clean_subgroup(subgrp, adj); /* If default originate is enabled and the route is default * route, do not send withdraw. This will prevent deletion of * the default route at the peer. */ if (CHECK_FLAG(subgrp->sflags, SUBGRP_STATUS_DEFAULT_ORIGINATE) && is_default_prefix(bgp_dest_get_prefix(dest))) return; if (adj->attr && withdraw) { /* We need advertisement structure. */ adj->adv = bgp_advertise_new(); adv = adj->adv; adv->dest = dest; adv->adj = adj; /* Note if we need to trigger a packet write */ trigger_write = !bgp_adv_fifo_count(&subgrp->sync->withdraw); /* Add to synchronization entry for withdraw * announcement. */ bgp_adv_fifo_add_tail(&subgrp->sync->withdraw, adv); if (trigger_write) subgroup_trigger_write(subgrp); } else { /* Free allocated information. */ adj_free(adj); } if (!CHECK_FLAG(subgrp->sflags, SUBGRP_STATUS_TABLE_REPARSING)) subgrp->pscount--; } subgrp->version = MAX(subgrp->version, dest->version); } void bgp_adj_out_remove_subgroup(struct bgp_dest *dest, struct bgp_adj_out *adj, struct update_subgroup *subgrp) { if (adj->attr) bgp_attr_unintern(&adj->attr); if (adj->adv) bgp_advertise_clean_subgroup(subgrp, adj); adj_free(adj); } /* * Go through all the routes and clean up the adj/adv structures corresponding * to the subgroup. */ void subgroup_clear_table(struct update_subgroup *subgrp) { struct bgp_adj_out *aout, *taout; SUBGRP_FOREACH_ADJ_SAFE (subgrp, aout, taout) bgp_adj_out_remove_subgroup(aout->dest, aout, subgrp); } /* * subgroup_announce_table */ void subgroup_announce_table(struct update_subgroup *subgrp, struct bgp_table *table) { struct bgp_dest *dest; struct bgp_path_info *ri; struct attr attr; struct peer *peer; afi_t afi; safi_t safi; bool addpath_capable; struct bgp *bgp; bool advertise; peer = SUBGRP_PEER(subgrp); afi = SUBGRP_AFI(subgrp); safi = SUBGRP_SAFI(subgrp); bgp = SUBGRP_INST(subgrp); addpath_capable = bgp_addpath_encode_tx(peer, afi, safi); if (safi == SAFI_LABELED_UNICAST) safi = SAFI_UNICAST; if (!table) table = peer->bgp->rib[afi][safi]; if (safi != SAFI_MPLS_VPN && safi != SAFI_ENCAP && safi != SAFI_EVPN && CHECK_FLAG(peer->af_flags[afi][safi], PEER_FLAG_DEFAULT_ORIGINATE)) subgroup_default_originate(subgrp, 0); subgrp->pscount = 0; SET_FLAG(subgrp->sflags, SUBGRP_STATUS_TABLE_REPARSING); for (dest = bgp_table_top(table); dest; dest = bgp_route_next(dest)) { const struct prefix *dest_p = bgp_dest_get_prefix(dest); /* Check if the route can be advertised */ advertise = bgp_check_advertise(bgp, dest); for (ri = bgp_dest_get_bgp_path_info(dest); ri; ri = ri->next) { if (!bgp_check_selected(ri, peer, addpath_capable, afi, safi)) continue; if (subgroup_announce_check(dest, ri, subgrp, dest_p, &attr, NULL)) { /* Check if route can be advertised */ if (advertise) { if (!bgp_check_withdrawal(bgp, dest)) bgp_adj_out_set_subgroup( dest, subgrp, &attr, ri); else bgp_adj_out_unset_subgroup( dest, subgrp, 1, bgp_addpath_id_for_peer( peer, afi, safi, &ri->tx_addpath)); } } else { /* If default originate is enabled for * the peer, do not send explicit * withdraw. This will prevent deletion * of default route advertised through * default originate */ if (CHECK_FLAG(peer->af_flags[afi][safi], PEER_FLAG_DEFAULT_ORIGINATE) && is_default_prefix( bgp_dest_get_prefix(dest))) break; bgp_adj_out_unset_subgroup( dest, subgrp, 1, bgp_addpath_id_for_peer( peer, afi, safi, &ri->tx_addpath)); } } } UNSET_FLAG(subgrp->sflags, SUBGRP_STATUS_TABLE_REPARSING); /* * We walked through the whole table -- make sure our version number * is consistent with the one on the table. This should allow * subgroups to merge sooner if a peer comes up when the route node * with the largest version is no longer in the table. This also * covers the pathological case where all routes in the table have * now been deleted. */ subgrp->version = MAX(subgrp->version, table->version); /* * Start a task to merge the subgroup if necessary. */ update_subgroup_trigger_merge_check(subgrp, 0); } /* * subgroup_announce_route * * Refresh all routes out to a subgroup. */ void subgroup_announce_route(struct update_subgroup *subgrp) { struct bgp_dest *dest; struct bgp_table *table; struct peer *onlypeer; if (update_subgroup_needs_refresh(subgrp)) { update_subgroup_set_needs_refresh(subgrp, 0); } /* * First update is deferred until ORF or ROUTE-REFRESH is received */ onlypeer = ((SUBGRP_PCOUNT(subgrp) == 1) ? (SUBGRP_PFIRST(subgrp))->peer : NULL); if (onlypeer && CHECK_FLAG(onlypeer->af_sflags[SUBGRP_AFI(subgrp)] [SUBGRP_SAFI(subgrp)], PEER_STATUS_ORF_WAIT_REFRESH)) return; if (SUBGRP_SAFI(subgrp) != SAFI_MPLS_VPN && SUBGRP_SAFI(subgrp) != SAFI_ENCAP && SUBGRP_SAFI(subgrp) != SAFI_EVPN) subgroup_announce_table(subgrp, NULL); else for (dest = bgp_table_top(update_subgroup_rib(subgrp)); dest; dest = bgp_route_next(dest)) { table = bgp_dest_get_bgp_table_info(dest); if (!table) continue; subgroup_announce_table(subgrp, table); } } void subgroup_default_originate(struct update_subgroup *subgrp, int withdraw) { struct bgp *bgp; struct attr attr; struct attr *new_attr = &attr; struct prefix p; struct peer *from; struct bgp_dest *dest; struct bgp_path_info *pi; struct peer *peer; struct bgp_adj_out *adj; route_map_result_t ret = RMAP_DENYMATCH; route_map_result_t new_ret = RMAP_DENYMATCH; afi_t afi; safi_t safi; int pref = 65536; int new_pref = 0; if (!subgrp) return; peer = SUBGRP_PEER(subgrp); afi = SUBGRP_AFI(subgrp); safi = SUBGRP_SAFI(subgrp); if (!(afi == AFI_IP || afi == AFI_IP6)) return; bgp = peer->bgp; from = bgp->peer_self; bgp_attr_default_set(&attr, bgp, BGP_ORIGIN_IGP); /* make coverity happy */ assert(attr.aspath); attr.med = 0; attr.flag |= ATTR_FLAG_BIT(BGP_ATTR_MULTI_EXIT_DISC); if ((afi == AFI_IP6) || peer_cap_enhe(peer, afi, safi)) { /* IPv6 global nexthop must be included. */ attr.mp_nexthop_len = BGP_ATTR_NHLEN_IPV6_GLOBAL; /* If the peer is on shared nextwork and we have link-local nexthop set it. */ if (peer->shared_network && !IN6_IS_ADDR_UNSPECIFIED(&peer->nexthop.v6_local)) attr.mp_nexthop_len = BGP_ATTR_NHLEN_IPV6_GLOBAL_AND_LL; } if (peer->default_rmap[afi][safi].name) { struct bgp_path_info tmp_pi = {0}; tmp_pi.peer = bgp->peer_self; SET_FLAG(bgp->peer_self->rmap_type, PEER_RMAP_TYPE_DEFAULT); /* Iterate over the RIB to see if we can announce * the default route. We announce the default * route only if route-map has a match. */ for (dest = bgp_table_top(bgp->rib[afi][safi]); dest; dest = bgp_route_next(dest)) { if (!bgp_dest_has_bgp_path_info_data(dest)) continue; for (pi = bgp_dest_get_bgp_path_info(dest); pi; pi = pi->next) { struct attr tmp_attr = attr; tmp_pi.attr = &tmp_attr; new_ret = route_map_apply_ext( peer->default_rmap[afi][safi].map, bgp_dest_get_prefix(dest), pi, &tmp_pi, &new_pref); if (new_ret == RMAP_PERMITMATCH) { if (new_pref < pref) { pref = new_pref; bgp_attr_flush(new_attr); new_attr = bgp_attr_intern( tmp_pi.attr); bgp_attr_flush(tmp_pi.attr); } subgroup_announce_reset_nhop( (peer_cap_enhe(peer, afi, safi) ? AF_INET6 : AF_INET), new_attr); ret = new_ret; } else bgp_attr_flush(&tmp_attr); } } bgp->peer_self->rmap_type = 0; if (ret == RMAP_DENYMATCH) { /* * If its a implicit withdraw due to routemap * deny operation need to set the flag back. * This is a convertion of update flow to * withdraw flow. */ if (!withdraw && (!CHECK_FLAG(subgrp->sflags, SUBGRP_STATUS_DEFAULT_ORIGINATE))) SET_FLAG(subgrp->sflags, SUBGRP_STATUS_DEFAULT_ORIGINATE); withdraw = 1; } } /* Check if the default route is in local BGP RIB which is * installed through redistribute or network command */ memset(&p, 0, sizeof(p)); p.family = afi2family(afi); p.prefixlen = 0; dest = bgp_afi_node_lookup(bgp->rib[afi][safi], afi, safi, &p, NULL); if (withdraw) { /* Withdraw the default route advertised using default * originate */ if (CHECK_FLAG(subgrp->sflags, SUBGRP_STATUS_DEFAULT_ORIGINATE)) subgroup_default_withdraw_packet(subgrp); UNSET_FLAG(subgrp->sflags, SUBGRP_STATUS_DEFAULT_ORIGINATE); /* If default route is present in the local RIB, advertise the * route */ if (dest) { for (pi = bgp_dest_get_bgp_path_info(dest); pi; pi = pi->next) { if (CHECK_FLAG(pi->flags, BGP_PATH_SELECTED)) if (subgroup_announce_check( dest, pi, subgrp, bgp_dest_get_prefix(dest), &attr, NULL)) { struct attr *default_attr = bgp_attr_intern(&attr); bgp_adj_out_set_subgroup( dest, subgrp, default_attr, pi); } } bgp_dest_unlock_node(dest); } } else { if (!CHECK_FLAG(subgrp->sflags, SUBGRP_STATUS_DEFAULT_ORIGINATE)) { /* The 'neighbor x.x.x.x default-originate' default will * act as an * implicit withdraw for any previous UPDATEs sent for * 0.0.0.0/0 so * clear adj_out for the 0.0.0.0/0 prefix in the BGP * table. */ if (dest) { /* Remove the adjacency for the previously * advertised default route */ adj = adj_lookup( dest, subgrp, BGP_ADDPATH_TX_ID_FOR_DEFAULT_ORIGINATE); if (adj != NULL) { /* Clean up previous advertisement. */ if (adj->adv) bgp_advertise_clean_subgroup( subgrp, adj); /* Free allocated information. */ adj_free(adj); } bgp_dest_unlock_node(dest); } /* Advertise the default route */ if (bgp_in_graceful_shutdown(bgp)) bgp_attr_add_gshut_community(new_attr); SET_FLAG(subgrp->sflags, SUBGRP_STATUS_DEFAULT_ORIGINATE); subgroup_default_update_packet(subgrp, new_attr, from); } } aspath_unintern(&attr.aspath); } /* * Announce the BGP table to a subgroup. * * At startup, we try to optimize route announcement by coalescing the * peer-up events. This is done only the first time - from then on, * subgrp->v_coalesce will be set to zero and the normal logic * prevails. */ void subgroup_announce_all(struct update_subgroup *subgrp) { if (!subgrp) return; /* * If coalesce timer value is not set, announce routes immediately. */ if (!subgrp->v_coalesce) { if (bgp_debug_update(NULL, NULL, subgrp->update_group, 0)) zlog_debug("u%" PRIu64 ":s%" PRIu64" announcing all routes", subgrp->update_group->id, subgrp->id); subgroup_announce_route(subgrp); return; } /* * We should wait for the coalesce timer. Arm the timer if not done. */ if (!subgrp->t_coalesce) { thread_add_timer_msec(bm->master, subgroup_coalesce_timer, subgrp, subgrp->v_coalesce, &subgrp->t_coalesce); } } /* * Go through all update subgroups and set up the adv queue for the * input route. */ void group_announce_route(struct bgp *bgp, afi_t afi, safi_t safi, struct bgp_dest *dest, struct bgp_path_info *pi) { struct updwalk_context ctx; ctx.pi = pi; ctx.dest = dest; /* If suppress fib is enabled, the route will be advertised when * FIB status is received */ if (!bgp_check_advertise(bgp, dest)) return; update_group_af_walk(bgp, afi, safi, group_announce_route_walkcb, &ctx); } void update_group_show_adj_queue(struct bgp *bgp, afi_t afi, safi_t safi, struct vty *vty, uint64_t id) { updgrp_show_adj(bgp, afi, safi, vty, id, UPDWALK_FLAGS_ADVQUEUE); } void update_group_show_advertised(struct bgp *bgp, afi_t afi, safi_t safi, struct vty *vty, uint64_t id) { updgrp_show_adj(bgp, afi, safi, vty, id, UPDWALK_FLAGS_ADVERTISED); } void update_group_announce(struct bgp *bgp) { update_group_walk(bgp, update_group_announce_walkcb, NULL); } void update_group_announce_rrclients(struct bgp *bgp) { update_group_walk(bgp, update_group_announce_rrc_walkcb, NULL); }