Adding upstream version 8.4.4.upstream/8.4.4upstream

Signed-off-by: Daniel Baumann <daniel.baumann@progress-linux.org>

1 files changed, 1315 insertions, 0 deletions

diff --git a/bgpd/bgp_updgrp_packet.c b/bgpd/bgp_updgrp_packet.c
new file mode 100644
index 0000000..344aea1
--- /dev/null
+++ b/bgpd/bgp_updgrp_packet.c
@@ -0,0 +1,1315 @@
+/**
+ * bgp_updgrp_packet.c: BGP update group packet handling routines
+ *
+ * @copyright Copyright (C) 2014 Cumulus Networks, Inc.
+ *
+ * @author Avneesh Sachdev <avneesh@sproute.net>
+ * @author Rajesh Varadarajan <rajesh@sproute.net>
+ * @author Pradosh Mohapatra <pradosh@sproute.net>
+ *
+ * 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 <zebra.h>
+
+#include "prefix.h"
+#include "thread.h"
+#include "buffer.h"
+#include "stream.h"
+#include "command.h"
+#include "sockunion.h"
+#include "network.h"
+#include "memory.h"
+#include "filter.h"
+#include "routemap.h"
+#include "log.h"
+#include "plist.h"
+#include "linklist.h"
+#include "workqueue.h"
+#include "hash.h"
+#include "queue.h"
+#include "mpls.h"
+
+#include "bgpd/bgpd.h"
+#include "bgpd/bgp_debug.h"
+#include "bgpd/bgp_errors.h"
+#include "bgpd/bgp_fsm.h"
+#include "bgpd/bgp_route.h"
+#include "bgpd/bgp_packet.h"
+#include "bgpd/bgp_advertise.h"
+#include "bgpd/bgp_updgrp.h"
+#include "bgpd/bgp_nexthop.h"
+#include "bgpd/bgp_nht.h"
+#include "bgpd/bgp_mplsvpn.h"
+#include "bgpd/bgp_label.h"
+#include "bgpd/bgp_addpath.h"
+
+/********************
+ * PRIVATE FUNCTIONS
+ ********************/
+
+/********************
+ * PUBLIC FUNCTIONS
+ ********************/
+struct bpacket *bpacket_alloc(void)
+{
+	struct bpacket *pkt;
+
+	pkt = XCALLOC(MTYPE_BGP_PACKET, sizeof(struct bpacket));
+
+	return pkt;
+}
+
+void bpacket_free(struct bpacket *pkt)
+{
+	if (pkt->buffer)
+		stream_free(pkt->buffer);
+	pkt->buffer = NULL;
+	XFREE(MTYPE_BGP_PACKET, pkt);
+}
+
+void bpacket_queue_init(struct bpacket_queue *q)
+{
+	TAILQ_INIT(&(q->pkts));
+}
+
+/*
+ * bpacket_queue_add_packet
+ *
+ * Internal function of bpacket_queue - and adds a
+ * packet entry to the end of the list.
+ *
+ * Users of bpacket_queue should use bpacket_queue_add instead.
+ */
+static void bpacket_queue_add_packet(struct bpacket_queue *q,
+				     struct bpacket *pkt)
+{
+	struct bpacket *last_pkt;
+
+	if (TAILQ_EMPTY(&(q->pkts)))
+		TAILQ_INSERT_TAIL(&(q->pkts), pkt, pkt_train);
+	else {
+		last_pkt = bpacket_queue_last(q);
+		TAILQ_INSERT_AFTER(&(q->pkts), last_pkt, pkt, pkt_train);
+	}
+	q->curr_count++;
+	if (q->hwm_count < q->curr_count)
+		q->hwm_count = q->curr_count;
+}
+
+/*
+ * Adds a packet to the bpacket_queue.
+ *
+ * The stream passed is consumed by this function. So, the caller should
+ * not free or use the stream after
+ * invoking this function.
+ */
+struct bpacket *bpacket_queue_add(struct bpacket_queue *q, struct stream *s,
+				  struct bpacket_attr_vec_arr *vecarrp)
+{
+	struct bpacket *pkt;
+	struct bpacket *last_pkt;
+
+
+	pkt = bpacket_alloc();
+	if (TAILQ_EMPTY(&(q->pkts))) {
+		pkt->ver = 1;
+		pkt->buffer = s;
+		if (vecarrp)
+			memcpy(&pkt->arr, vecarrp,
+			       sizeof(struct bpacket_attr_vec_arr));
+		else
+			bpacket_attr_vec_arr_reset(&pkt->arr);
+		bpacket_queue_add_packet(q, pkt);
+		return pkt;
+	}
+
+	/*
+	 * Fill in the new information into the current sentinel and create a
+	 * new sentinel.
+	 */
+	last_pkt = bpacket_queue_last(q);
+	assert(last_pkt->buffer == NULL);
+	last_pkt->buffer = s;
+	if (vecarrp)
+		memcpy(&last_pkt->arr, vecarrp,
+		       sizeof(struct bpacket_attr_vec_arr));
+	else
+		bpacket_attr_vec_arr_reset(&last_pkt->arr);
+
+	pkt->ver = last_pkt->ver;
+	pkt->ver++;
+	bpacket_queue_add_packet(q, pkt);
+
+	return last_pkt;
+}
+
+struct bpacket *bpacket_queue_first(struct bpacket_queue *q)
+{
+	return (TAILQ_FIRST(&(q->pkts)));
+}
+
+struct bpacket *bpacket_queue_last(struct bpacket_queue *q)
+{
+	return TAILQ_LAST(&(q->pkts), pkt_queue);
+}
+
+struct bpacket *bpacket_queue_remove(struct bpacket_queue *q)
+{
+	struct bpacket *first;
+
+	first = bpacket_queue_first(q);
+	if (first) {
+		TAILQ_REMOVE(&(q->pkts), first, pkt_train);
+		q->curr_count--;
+	}
+	return first;
+}
+
+unsigned int bpacket_queue_length(struct bpacket_queue *q)
+{
+	return q->curr_count - 1;
+}
+
+unsigned int bpacket_queue_hwm_length(struct bpacket_queue *q)
+{
+	return q->hwm_count - 1;
+}
+
+bool bpacket_queue_is_full(struct bgp *bgp, struct bpacket_queue *q)
+{
+	if (q->curr_count >= bgp->default_subgroup_pkt_queue_max)
+		return true;
+	return false;
+}
+
+void bpacket_add_peer(struct bpacket *pkt, struct peer_af *paf)
+{
+	if (!pkt || !paf)
+		return;
+
+	LIST_INSERT_HEAD(&(pkt->peers), paf, pkt_train);
+	paf->next_pkt_to_send = pkt;
+}
+
+/*
+ * bpacket_queue_cleanup
+ */
+void bpacket_queue_cleanup(struct bpacket_queue *q)
+{
+	struct bpacket *pkt;
+
+	while ((pkt = bpacket_queue_remove(q))) {
+		bpacket_free(pkt);
+	}
+}
+
+/*
+ * bpacket_queue_compact
+ *
+ * Delete packets that do not need to be transmitted to any peer from
+ * the queue.
+ *
+ * @return the number of packets deleted.
+ */
+static int bpacket_queue_compact(struct bpacket_queue *q)
+{
+	int num_deleted;
+	struct bpacket *pkt, *removed_pkt;
+
+	num_deleted = 0;
+
+	while (1) {
+		pkt = bpacket_queue_first(q);
+		if (!pkt)
+			break;
+
+		/*
+		 * Don't delete the sentinel.
+		 */
+		if (!pkt->buffer)
+			break;
+
+		if (!LIST_EMPTY(&(pkt->peers)))
+			break;
+
+		removed_pkt = bpacket_queue_remove(q);
+		assert(pkt == removed_pkt);
+		bpacket_free(removed_pkt);
+
+		num_deleted++;
+	}
+
+	return num_deleted;
+}
+
+void bpacket_queue_advance_peer(struct peer_af *paf)
+{
+	struct bpacket *pkt;
+	struct bpacket *old_pkt;
+
+	old_pkt = paf->next_pkt_to_send;
+	if (old_pkt->buffer == NULL)
+		/* Already at end of list */
+		return;
+
+	LIST_REMOVE(paf, pkt_train);
+	pkt = TAILQ_NEXT(old_pkt, pkt_train);
+	bpacket_add_peer(pkt, paf);
+
+	if (!bpacket_queue_compact(PAF_PKTQ(paf)))
+		return;
+
+	/*
+	 * Deleted one or more packets. Check if we can now merge this
+	 * peer's subgroup into another subgroup.
+	 */
+	update_subgroup_check_merge(paf->subgroup, "advanced peer in queue");
+}
+
+/*
+ * bpacket_queue_remove_peer
+ *
+ * Remove the peer from the packet queue of the subgroup it belongs
+ * to.
+ */
+void bpacket_queue_remove_peer(struct peer_af *paf)
+{
+	struct bpacket_queue *q;
+
+	q = PAF_PKTQ(paf);
+	assert(q);
+
+	LIST_REMOVE(paf, pkt_train);
+	paf->next_pkt_to_send = NULL;
+
+	bpacket_queue_compact(q);
+}
+
+unsigned int bpacket_queue_virtual_length(struct peer_af *paf)
+{
+	struct bpacket *pkt;
+	struct bpacket *last;
+	struct bpacket_queue *q;
+
+	pkt = paf->next_pkt_to_send;
+	if (!pkt || (pkt->buffer == NULL))
+		/* Already at end of list */
+		return 0;
+
+	q = PAF_PKTQ(paf);
+	if (TAILQ_EMPTY(&(q->pkts)))
+		return 0;
+
+	last = TAILQ_LAST(&(q->pkts), pkt_queue);
+	if (last->ver >= pkt->ver)
+		return last->ver - pkt->ver;
+
+	/* sequence # rolled over */
+	return (UINT_MAX - pkt->ver + 1) + last->ver;
+}
+
+/*
+ * Dump the bpacket queue
+ */
+void bpacket_queue_show_vty(struct bpacket_queue *q, struct vty *vty)
+{
+	struct bpacket *pkt;
+	struct peer_af *paf;
+
+	pkt = bpacket_queue_first(q);
+	while (pkt) {
+		vty_out(vty, "  Packet %p ver %u buffer %p\n", pkt, pkt->ver,
+			pkt->buffer);
+
+		LIST_FOREACH (paf, &(pkt->peers), pkt_train) {
+			vty_out(vty, "      - %s\n", paf->peer->host);
+		}
+		pkt = bpacket_next(pkt);
+	}
+	return;
+}
+
+struct stream *bpacket_reformat_for_peer(struct bpacket *pkt,
+					 struct peer_af *paf)
+{
+	struct stream *s = NULL;
+	bpacket_attr_vec *vec;
+	struct peer *peer;
+	struct bgp_filter *filter;
+
+	s = stream_dup(pkt->buffer);
+	peer = PAF_PEER(paf);
+
+	vec = &pkt->arr.entries[BGP_ATTR_VEC_NH];
+
+	if (!CHECK_FLAG(vec->flags, BPKT_ATTRVEC_FLAGS_UPDATED))
+		return s;
+
+	uint8_t nhlen;
+	afi_t nhafi;
+	int route_map_sets_nh;
+
+	nhlen = stream_getc_from(s, vec->offset);
+	filter = &peer->filter[paf->afi][paf->safi];
+
+	if (peer_cap_enhe(peer, paf->afi, paf->safi))
+		nhafi = AFI_IP6;
+	else
+		nhafi = BGP_NEXTHOP_AFI_FROM_NHLEN(nhlen);
+
+	if (nhafi == AFI_IP) {
+		struct in_addr v4nh, *mod_v4nh;
+		int nh_modified = 0;
+		size_t offset_nh = vec->offset + 1;
+
+		route_map_sets_nh =
+			(CHECK_FLAG(vec->flags,
+				    BPKT_ATTRVEC_FLAGS_RMAP_IPV4_NH_CHANGED)
+			 || CHECK_FLAG(
+				 vec->flags,
+				 BPKT_ATTRVEC_FLAGS_RMAP_NH_PEER_ADDRESS));
+
+		switch (nhlen) {
+		case BGP_ATTR_NHLEN_IPV4:
+			break;
+		case BGP_ATTR_NHLEN_VPNV4:
+			offset_nh += 8;
+			break;
+		default:
+			/* TODO: handle IPv6 nexthops */
+			flog_warn(
+				EC_BGP_INVALID_NEXTHOP_LENGTH,
+				"%s: %s: invalid MP nexthop length (AFI IP): %u",
+				__func__, peer->host, nhlen);
+			stream_free(s);
+			return NULL;
+		}
+
+		stream_get_from(&v4nh, s, offset_nh, IPV4_MAX_BYTELEN);
+		mod_v4nh = &v4nh;
+
+		/*
+		 * If route-map has set the nexthop, that is normally
+		 * used; if it is specified as peer-address, the peering
+		 * address is picked up. Otherwise, if NH is unavailable
+		 * from attribute, the peering addr is picked up; the
+		 * "NH unavailable" case also covers next-hop-self and
+		 * some other scenarios - see subgroup_announce_check().
+		 * In all other cases, use the nexthop carried in the
+		 * attribute unless it is EBGP non-multiaccess and there
+		 * is no next-hop-unchanged setting or the peer is EBGP
+		 * and the route-map that changed the next-hop value
+		 * was applied inbound rather than outbound. Updates to
+		 * an EBGP peer should only modify the next-hop if it
+		 * was set in an outbound route-map to that peer.
+		 * Note: It is assumed route-map cannot set the nexthop
+		 * to an invalid value.
+		 */
+		if (route_map_sets_nh
+		    && ((peer->sort != BGP_PEER_EBGP)
+			|| ROUTE_MAP_OUT(filter))) {
+			if (CHECK_FLAG(
+				    vec->flags,
+				    BPKT_ATTRVEC_FLAGS_RMAP_NH_PEER_ADDRESS)) {
+				mod_v4nh = &peer->nexthop.v4;
+				nh_modified = 1;
+			}
+		} else if (v4nh.s_addr == INADDR_ANY) {
+			mod_v4nh = &peer->nexthop.v4;
+			nh_modified = 1;
+		} else if (peer->sort == BGP_PEER_EBGP
+			   && (bgp_multiaccess_check_v4(v4nh, peer) == 0)
+			   && !CHECK_FLAG(vec->flags,
+					  BPKT_ATTRVEC_FLAGS_RMAP_NH_UNCHANGED)
+			   && !peer_af_flag_check(
+				   peer, paf->afi, paf->safi,
+				   PEER_FLAG_NEXTHOP_UNCHANGED)) {
+			/* NOTE: not handling case where NH has new AFI
+			 */
+			mod_v4nh = &peer->nexthop.v4;
+			nh_modified = 1;
+		}
+
+		if (nh_modified) /* allow for VPN RD */
+			stream_put_in_addr_at(s, offset_nh, mod_v4nh);
+
+		if (bgp_debug_update(peer, NULL, NULL, 0))
+			zlog_debug("u%" PRIu64 ":s%" PRIu64
+				   " %s send UPDATE w/ nexthop %pI4%s",
+				   PAF_SUBGRP(paf)->update_group->id,
+				   PAF_SUBGRP(paf)->id, peer->host, mod_v4nh,
+				   (nhlen == BGP_ATTR_NHLEN_VPNV4 ? " and RD"
+								  : ""));
+	} else if (nhafi == AFI_IP6) {
+		struct in6_addr v6nhglobal, *mod_v6nhg;
+		struct in6_addr v6nhlocal, *mod_v6nhl;
+		int gnh_modified, lnh_modified;
+		size_t offset_nhglobal = vec->offset + 1;
+		size_t offset_nhlocal = vec->offset + 1;
+
+		gnh_modified = lnh_modified = 0;
+		mod_v6nhg = &v6nhglobal;
+		mod_v6nhl = &v6nhlocal;
+
+		route_map_sets_nh =
+			(CHECK_FLAG(vec->flags,
+				    BPKT_ATTRVEC_FLAGS_RMAP_IPV6_GNH_CHANGED)
+			 || CHECK_FLAG(
+				 vec->flags,
+				 BPKT_ATTRVEC_FLAGS_RMAP_NH_PEER_ADDRESS));
+
+		/*
+		 * The logic here is rather similar to that for IPv4, the
+		 * additional work being to handle 1 or 2 nexthops.
+		 * Also, 3rd party nexthop is not propagated for EBGP
+		 * right now.
+		 */
+		switch (nhlen) {
+		case BGP_ATTR_NHLEN_IPV6_GLOBAL:
+			break;
+		case BGP_ATTR_NHLEN_IPV6_GLOBAL_AND_LL:
+			offset_nhlocal += IPV6_MAX_BYTELEN;
+			break;
+		case BGP_ATTR_NHLEN_VPNV6_GLOBAL:
+			offset_nhglobal += 8;
+			break;
+		case BGP_ATTR_NHLEN_VPNV6_GLOBAL_AND_LL:
+			offset_nhglobal += 8;
+			offset_nhlocal += 8 * 2 + IPV6_MAX_BYTELEN;
+			break;
+		default:
+			/* TODO: handle IPv4 nexthops */
+			flog_warn(
+				EC_BGP_INVALID_NEXTHOP_LENGTH,
+				"%s: %s: invalid MP nexthop length (AFI IP6): %u",
+				__func__, peer->host, nhlen);
+			stream_free(s);
+			return NULL;
+		}
+
+		stream_get_from(&v6nhglobal, s, offset_nhglobal,
+				IPV6_MAX_BYTELEN);
+
+		/*
+		 * Updates to an EBGP peer should only modify the
+		 * next-hop if it was set in an outbound route-map
+		 * to that peer.
+		 */
+		if (route_map_sets_nh
+		    && ((peer->sort != BGP_PEER_EBGP)
+			|| ROUTE_MAP_OUT(filter))) {
+			if (CHECK_FLAG(
+				    vec->flags,
+				    BPKT_ATTRVEC_FLAGS_RMAP_NH_PEER_ADDRESS)) {
+				mod_v6nhg = &peer->nexthop.v6_global;
+				gnh_modified = 1;
+			}
+		} else if (IN6_IS_ADDR_UNSPECIFIED(&v6nhglobal)) {
+			mod_v6nhg = &peer->nexthop.v6_global;
+			gnh_modified = 1;
+		} else if ((peer->sort == BGP_PEER_EBGP)
+			   && (!bgp_multiaccess_check_v6(v6nhglobal, peer))
+			   && !CHECK_FLAG(vec->flags,
+					  BPKT_ATTRVEC_FLAGS_RMAP_NH_UNCHANGED)
+			   && !peer_af_flag_check(
+				   peer, paf->afi, paf->safi,
+				   PEER_FLAG_NEXTHOP_UNCHANGED)) {
+			/* NOTE: not handling case where NH has new AFI
+			 */
+			mod_v6nhg = &peer->nexthop.v6_global;
+			gnh_modified = 1;
+		}
+
+		if (IN6_IS_ADDR_UNSPECIFIED(mod_v6nhg)) {
+			if (peer->nexthop.v4.s_addr != INADDR_ANY) {
+				ipv4_to_ipv4_mapped_ipv6(mod_v6nhg,
+							 peer->nexthop.v4);
+			}
+		}
+
+		if (IS_MAPPED_IPV6(&peer->nexthop.v6_global)) {
+			mod_v6nhg = &peer->nexthop.v6_global;
+			gnh_modified = 1;
+		}
+
+		if (nhlen == BGP_ATTR_NHLEN_IPV6_GLOBAL_AND_LL
+		    || nhlen == BGP_ATTR_NHLEN_VPNV6_GLOBAL_AND_LL) {
+			stream_get_from(&v6nhlocal, s, offset_nhlocal,
+					IPV6_MAX_BYTELEN);
+			if (IN6_IS_ADDR_UNSPECIFIED(&v6nhlocal)) {
+				mod_v6nhl = &peer->nexthop.v6_local;
+				lnh_modified = 1;
+			}
+		}
+
+		if (gnh_modified)
+			stream_put_in6_addr_at(s, offset_nhglobal, mod_v6nhg);
+		if (lnh_modified)
+			stream_put_in6_addr_at(s, offset_nhlocal, mod_v6nhl);
+
+		if (bgp_debug_update(peer, NULL, NULL, 0)) {
+			if (nhlen == BGP_ATTR_NHLEN_IPV6_GLOBAL_AND_LL
+			    || nhlen == BGP_ATTR_NHLEN_VPNV6_GLOBAL_AND_LL)
+				zlog_debug(
+					"u%" PRIu64 ":s%" PRIu64
+					" %s send UPDATE w/ mp_nexthops %pI6, %pI6%s",
+					PAF_SUBGRP(paf)->update_group->id,
+					PAF_SUBGRP(paf)->id, peer->host,
+					mod_v6nhg, mod_v6nhl,
+					(nhlen == BGP_ATTR_NHLEN_VPNV6_GLOBAL_AND_LL
+						 ? " and RD"
+						 : ""));
+			else
+				zlog_debug(
+					"u%" PRIu64 ":s%" PRIu64
+					" %s send UPDATE w/ mp_nexthop %pI6%s",
+					PAF_SUBGRP(paf)->update_group->id,
+					PAF_SUBGRP(paf)->id, peer->host,
+					mod_v6nhg,
+					(nhlen == BGP_ATTR_NHLEN_VPNV6_GLOBAL
+						 ? " and RD"
+						 : ""));
+		}
+	} else if (paf->afi == AFI_L2VPN) {
+		struct in_addr v4nh, *mod_v4nh;
+		int nh_modified = 0;
+
+		stream_get_from(&v4nh, s, vec->offset + 1, 4);
+		mod_v4nh = &v4nh;
+
+		/* No route-map changes allowed for EVPN nexthops. */
+		if (v4nh.s_addr == INADDR_ANY) {
+			mod_v4nh = &peer->nexthop.v4;
+			nh_modified = 1;
+		}
+
+		if (nh_modified)
+			stream_put_in_addr_at(s, vec->offset + 1, mod_v4nh);
+
+		if (bgp_debug_update(peer, NULL, NULL, 0))
+			zlog_debug("u%" PRIu64 ":s%" PRIu64
+				   " %s send UPDATE w/ nexthop %pI4",
+				   PAF_SUBGRP(paf)->update_group->id,
+				   PAF_SUBGRP(paf)->id, peer->host, mod_v4nh);
+	}
+
+	return s;
+}
+
+/*
+ * Update the vecarr offsets to go beyond 'pos' bytes, i.e. add 'pos'
+ * to each offset.
+ */
+static void bpacket_attr_vec_arr_update(struct bpacket_attr_vec_arr *vecarr,
+					size_t pos)
+{
+	int i;
+
+	if (!vecarr)
+		return;
+
+	for (i = 0; i < BGP_ATTR_VEC_MAX; i++)
+		vecarr->entries[i].offset += pos;
+}
+
+/*
+ * Return if there are packets to build for this subgroup.
+ */
+bool subgroup_packets_to_build(struct update_subgroup *subgrp)
+{
+	struct bgp_advertise *adv;
+
+	if (!subgrp)
+		return false;
+
+	adv = bgp_adv_fifo_first(&subgrp->sync->withdraw);
+	if (adv)
+		return true;
+
+	adv = bgp_adv_fifo_first(&subgrp->sync->update);
+	if (adv)
+		return true;
+
+	return false;
+}
+
+/* Make BGP update packet.  */
+struct bpacket *subgroup_update_packet(struct update_subgroup *subgrp)
+{
+	struct bpacket_attr_vec_arr vecarr;
+	struct bpacket *pkt;
+	struct peer *peer;
+	struct stream *s;
+	struct stream *snlri;
+	struct stream *packet;
+	struct bgp_adj_out *adj;
+	struct bgp_advertise *adv;
+	struct bgp_dest *dest = NULL;
+	struct bgp_path_info *path = NULL;
+	bgp_size_t total_attr_len = 0;
+	unsigned long attrlen_pos = 0;
+	size_t mpattrlen_pos = 0;
+	size_t mpattr_pos = 0;
+	afi_t afi;
+	safi_t safi;
+	int space_remaining = 0;
+	int space_needed = 0;
+	char send_attr_str[BUFSIZ];
+	int send_attr_printed = 0;
+	int num_pfx = 0;
+	bool addpath_capable = false;
+	int addpath_overhead = 0;
+	uint32_t addpath_tx_id = 0;
+	struct prefix_rd *prd = NULL;
+	mpls_label_t label = MPLS_INVALID_LABEL, *label_pnt = NULL;
+	uint32_t num_labels = 0;
+
+	if (!subgrp)
+		return NULL;
+
+	if (bpacket_queue_is_full(SUBGRP_INST(subgrp), SUBGRP_PKTQ(subgrp)))
+		return NULL;
+
+	peer = SUBGRP_PEER(subgrp);
+	afi = SUBGRP_AFI(subgrp);
+	safi = SUBGRP_SAFI(subgrp);
+	s = subgrp->work;
+	stream_reset(s);
+	snlri = subgrp->scratch;
+	stream_reset(snlri);
+
+	bpacket_attr_vec_arr_reset(&vecarr);
+
+	addpath_capable = bgp_addpath_encode_tx(peer, afi, safi);
+	addpath_overhead = addpath_capable ? BGP_ADDPATH_ID_LEN : 0;
+
+	adv = bgp_adv_fifo_first(&subgrp->sync->update);
+	while (adv) {
+		const struct prefix *dest_p;
+
+		assert(adv->dest);
+		dest = adv->dest;
+		dest_p = bgp_dest_get_prefix(dest);
+		adj = adv->adj;
+		addpath_tx_id = adj->addpath_tx_id;
+		path = adv->pathi;
+
+		space_remaining = STREAM_CONCAT_REMAIN(s, snlri, STREAM_SIZE(s))
+				  - BGP_MAX_PACKET_SIZE_OVERFLOW;
+		space_needed =
+			BGP_NLRI_LENGTH + addpath_overhead
+			+ bgp_packet_mpattr_prefix_size(afi, safi, dest_p);
+
+		/* When remaining space can't include NLRI and it's length.  */
+		if (space_remaining < space_needed)
+			break;
+
+		/* If packet is empty, set attribute. */
+		if (stream_empty(s)) {
+			struct peer *from = NULL;
+
+			if (path)
+				from = path->peer;
+
+			/* 1: Write the BGP message header - 16 bytes marker, 2
+			 * bytes length,
+			 * one byte message type.
+			 */
+			bgp_packet_set_marker(s, BGP_MSG_UPDATE);
+
+			/* 2: withdrawn routes length */
+			stream_putw(s, 0);
+
+			/* 3: total attributes length - attrlen_pos stores the
+			 * position */
+			attrlen_pos = stream_get_endp(s);
+			stream_putw(s, 0);
+
+			/* 4: if there is MP_REACH_NLRI attribute, that should
+			 * be the first
+			 * attribute, according to
+			 * draft-ietf-idr-error-handling. Save the
+			 * position.
+			 */
+			mpattr_pos = stream_get_endp(s);
+
+			/* 5: Encode all the attributes, except MP_REACH_NLRI
+			 * attr. */
+			total_attr_len = bgp_packet_attribute(
+				NULL, peer, s, adv->baa->attr, &vecarr, NULL,
+				afi, safi, from, NULL, NULL, 0, 0, 0);
+
+			space_remaining =
+				STREAM_CONCAT_REMAIN(s, snlri, STREAM_SIZE(s))
+				- BGP_MAX_PACKET_SIZE_OVERFLOW;
+			space_needed = BGP_NLRI_LENGTH + addpath_overhead
+				       + bgp_packet_mpattr_prefix_size(
+					       afi, safi, dest_p);
+
+			/* If the attributes alone do not leave any room for
+			 * NLRI then
+			 * return */
+			if (space_remaining < space_needed) {
+				flog_err(
+					EC_BGP_UPDGRP_ATTR_LEN,
+					"u%" PRIu64 ":s%" PRIu64" attributes too long, cannot send UPDATE",
+					subgrp->update_group->id, subgrp->id);
+
+				/* Flush the FIFO update queue */
+				while (adv)
+					adv = bgp_advertise_clean_subgroup(
+						subgrp, adj);
+				return NULL;
+			}
+
+			if (BGP_DEBUG(update, UPDATE_OUT)
+			    || BGP_DEBUG(update, UPDATE_PREFIX)) {
+				memset(send_attr_str, 0, BUFSIZ);
+				send_attr_printed = 0;
+				bgp_dump_attr(adv->baa->attr, send_attr_str,
+					      sizeof(send_attr_str));
+			}
+		}
+
+		if ((afi == AFI_IP && safi == SAFI_UNICAST)
+		    && !peer_cap_enhe(peer, afi, safi))
+			stream_put_prefix_addpath(s, dest_p, addpath_capable,
+						  addpath_tx_id);
+		else {
+			/* Encode the prefix in MP_REACH_NLRI attribute */
+			if (dest->pdest)
+				prd = (struct prefix_rd *)bgp_dest_get_prefix(
+					dest->pdest);
+
+			if (safi == SAFI_LABELED_UNICAST) {
+				label = bgp_adv_label(dest, path, peer, afi,
+						      safi);
+				label_pnt = &label;
+				num_labels = 1;
+			} else if (path && path->extra) {
+				label_pnt = &path->extra->label[0];
+				num_labels = path->extra->num_labels;
+			}
+
+			if (stream_empty(snlri))
+				mpattrlen_pos = bgp_packet_mpattr_start(
+					snlri, peer, afi, safi, &vecarr,
+					adv->baa->attr);
+
+			bgp_packet_mpattr_prefix(snlri, afi, safi, dest_p, prd,
+						 label_pnt, num_labels,
+						 addpath_capable, addpath_tx_id,
+						 adv->baa->attr);
+		}
+
+		num_pfx++;
+
+		if (bgp_debug_update(NULL, dest_p, subgrp->update_group, 0)) {
+			char pfx_buf[BGP_PRD_PATH_STRLEN];
+
+			if (!send_attr_printed) {
+				zlog_debug("u%" PRIu64 ":s%" PRIu64" send UPDATE w/ attr: %s",
+					   subgrp->update_group->id, subgrp->id,
+					   send_attr_str);
+				if (!stream_empty(snlri)) {
+					iana_afi_t pkt_afi;
+					iana_safi_t pkt_safi;
+
+					pkt_afi = afi_int2iana(afi);
+					pkt_safi = safi_int2iana(safi);
+					zlog_debug(
+						"u%" PRIu64 ":s%" PRIu64
+						" send MP_REACH for afi/safi %s/%s",
+						subgrp->update_group->id,
+						subgrp->id,
+						iana_afi2str(pkt_afi),
+						iana_safi2str(pkt_safi));
+				}
+
+				send_attr_printed = 1;
+			}
+
+			bgp_debug_rdpfxpath2str(afi, safi, prd, dest_p,
+						label_pnt, num_labels,
+						addpath_capable, addpath_tx_id,
+						&adv->baa->attr->evpn_overlay,
+						pfx_buf, sizeof(pfx_buf));
+			zlog_debug("u%" PRIu64 ":s%" PRIu64 " send UPDATE %s",
+				   subgrp->update_group->id, subgrp->id,
+				   pfx_buf);
+		}
+
+		/* Synchnorize attribute.  */
+		if (adj->attr)
+			bgp_attr_unintern(&adj->attr);
+		else
+			subgrp->scount++;
+
+		adj->attr = bgp_attr_intern(adv->baa->attr);
+		adv = bgp_advertise_clean_subgroup(subgrp, adj);
+	}
+
+	if (!stream_empty(s)) {
+		if (!stream_empty(snlri)) {
+			bgp_packet_mpattr_end(snlri, mpattrlen_pos);
+			total_attr_len += stream_get_endp(snlri);
+		}
+
+		/* set the total attribute length correctly */
+		stream_putw_at(s, attrlen_pos, total_attr_len);
+
+		if (!stream_empty(snlri)) {
+			packet = stream_dupcat(s, snlri, mpattr_pos);
+			bpacket_attr_vec_arr_update(&vecarr, mpattr_pos);
+		} else
+			packet = stream_dup(s);
+		bgp_packet_set_size(packet);
+		if (bgp_debug_update(NULL, NULL, subgrp->update_group, 0))
+			zlog_debug(
+				"u%" PRIu64 ":s%" PRIu64
+				" send UPDATE len %zd (max message len: %hu) numpfx %d",
+				subgrp->update_group->id, subgrp->id,
+				(stream_get_endp(packet)
+				 - stream_get_getp(packet)),
+				peer->max_packet_size, num_pfx);
+		pkt = bpacket_queue_add(SUBGRP_PKTQ(subgrp), packet, &vecarr);
+		stream_reset(s);
+		stream_reset(snlri);
+		return pkt;
+	}
+	return NULL;
+}
+
+/* Make BGP withdraw packet.  */
+/* For ipv4 unicast:
+   16-octet marker | 2-octet length | 1-octet type |
+    2-octet withdrawn route length | withdrawn prefixes | 2-octet attrlen (=0)
+*/
+/* For other afi/safis:
+   16-octet marker | 2-octet length | 1-octet type |
+    2-octet withdrawn route length (=0) | 2-octet attrlen |
+     mp_unreach attr type | attr len | afi | safi | withdrawn prefixes
+*/
+struct bpacket *subgroup_withdraw_packet(struct update_subgroup *subgrp)
+{
+	struct bpacket *pkt;
+	struct stream *s;
+	struct bgp_adj_out *adj;
+	struct bgp_advertise *adv;
+	struct peer *peer;
+	struct bgp_dest *dest;
+	bgp_size_t unfeasible_len;
+	bgp_size_t total_attr_len;
+	size_t mp_start = 0;
+	size_t attrlen_pos = 0;
+	size_t mplen_pos = 0;
+	uint8_t first_time = 1;
+	afi_t afi;
+	safi_t safi;
+	int space_remaining = 0;
+	int space_needed = 0;
+	int num_pfx = 0;
+	bool addpath_capable = false;
+	int addpath_overhead = 0;
+	uint32_t addpath_tx_id = 0;
+	const struct prefix_rd *prd = NULL;
+
+
+	if (!subgrp)
+		return NULL;
+
+	if (bpacket_queue_is_full(SUBGRP_INST(subgrp), SUBGRP_PKTQ(subgrp)))
+		return NULL;
+
+	peer = SUBGRP_PEER(subgrp);
+	afi = SUBGRP_AFI(subgrp);
+	safi = SUBGRP_SAFI(subgrp);
+	s = subgrp->work;
+	stream_reset(s);
+	addpath_capable = bgp_addpath_encode_tx(peer, afi, safi);
+	addpath_overhead = addpath_capable ? BGP_ADDPATH_ID_LEN : 0;
+
+	while ((adv = bgp_adv_fifo_first(&subgrp->sync->withdraw)) != NULL) {
+		const struct prefix *dest_p;
+
+		assert(adv->dest);
+		adj = adv->adj;
+		dest = adv->dest;
+		dest_p = bgp_dest_get_prefix(dest);
+		addpath_tx_id = adj->addpath_tx_id;
+
+		space_remaining =
+			STREAM_WRITEABLE(s) - BGP_MAX_PACKET_SIZE_OVERFLOW;
+		space_needed =
+			BGP_NLRI_LENGTH + addpath_overhead + BGP_TOTAL_ATTR_LEN
+			+ bgp_packet_mpattr_prefix_size(afi, safi, dest_p);
+
+		if (space_remaining < space_needed)
+			break;
+
+		if (stream_empty(s)) {
+			bgp_packet_set_marker(s, BGP_MSG_UPDATE);
+			stream_putw(s, 0); /* unfeasible routes length */
+		} else
+			first_time = 0;
+
+		if (afi == AFI_IP && safi == SAFI_UNICAST
+		    && !peer_cap_enhe(peer, afi, safi))
+			stream_put_prefix_addpath(s, dest_p, addpath_capable,
+						  addpath_tx_id);
+		else {
+			if (dest->pdest)
+				prd = (struct prefix_rd *)bgp_dest_get_prefix(
+					dest->pdest);
+
+			/* If first time, format the MP_UNREACH header
+			 */
+			if (first_time) {
+				iana_afi_t pkt_afi;
+				iana_safi_t pkt_safi;
+
+				pkt_afi = afi_int2iana(afi);
+				pkt_safi = safi_int2iana(safi);
+
+				attrlen_pos = stream_get_endp(s);
+				/* total attr length = 0 for now.
+				 * reevaluate later */
+				stream_putw(s, 0);
+				mp_start = stream_get_endp(s);
+				mplen_pos = bgp_packet_mpunreach_start(s, afi,
+								       safi);
+				if (bgp_debug_update(NULL, NULL,
+						     subgrp->update_group, 0))
+					zlog_debug(
+						"u%" PRIu64 ":s%" PRIu64
+						" send MP_UNREACH for afi/safi %s/%s",
+						subgrp->update_group->id,
+						subgrp->id,
+						iana_afi2str(pkt_afi),
+						iana_safi2str(pkt_safi));
+			}
+
+			bgp_packet_mpunreach_prefix(s, dest_p, afi, safi, prd,
+						    NULL, 0, addpath_capable,
+						    addpath_tx_id, NULL);
+		}
+
+		num_pfx++;
+
+		if (bgp_debug_update(NULL, dest_p, subgrp->update_group, 0)) {
+			char pfx_buf[BGP_PRD_PATH_STRLEN];
+
+			bgp_debug_rdpfxpath2str(afi, safi, prd, dest_p, NULL, 0,
+						addpath_capable, addpath_tx_id,
+						NULL, pfx_buf, sizeof(pfx_buf));
+			zlog_debug("u%" PRIu64 ":s%" PRIu64" send UPDATE %s -- unreachable",
+				   subgrp->update_group->id, subgrp->id,
+				   pfx_buf);
+		}
+
+		subgrp->scount--;
+
+		bgp_adj_out_remove_subgroup(dest, adj, subgrp);
+	}
+
+	if (!stream_empty(s)) {
+		if (afi == AFI_IP && safi == SAFI_UNICAST
+		    && !peer_cap_enhe(peer, afi, safi)) {
+			unfeasible_len = stream_get_endp(s) - BGP_HEADER_SIZE
+					 - BGP_UNFEASIBLE_LEN;
+			stream_putw_at(s, BGP_HEADER_SIZE, unfeasible_len);
+			stream_putw(s, 0);
+		} else {
+			/* Set the mp_unreach attr's length */
+			bgp_packet_mpunreach_end(s, mplen_pos);
+
+			/* Set total path attribute length. */
+			total_attr_len = stream_get_endp(s) - mp_start;
+			stream_putw_at(s, attrlen_pos, total_attr_len);
+		}
+		bgp_packet_set_size(s);
+		if (bgp_debug_update(NULL, NULL, subgrp->update_group, 0))
+			zlog_debug("u%" PRIu64 ":s%" PRIu64" send UPDATE (withdraw) len %zd numpfx %d",
+				   subgrp->update_group->id, subgrp->id,
+				   (stream_get_endp(s) - stream_get_getp(s)),
+				   num_pfx);
+		pkt = bpacket_queue_add(SUBGRP_PKTQ(subgrp), stream_dup(s),
+					NULL);
+		stream_reset(s);
+		return pkt;
+	}
+
+	return NULL;
+}
+
+void subgroup_default_update_packet(struct update_subgroup *subgrp,
+				    struct attr *attr, struct peer *from)
+{
+	struct stream *s;
+	struct peer *peer;
+	struct prefix p;
+	unsigned long pos;
+	bgp_size_t total_attr_len;
+	afi_t afi;
+	safi_t safi;
+	struct bpacket_attr_vec_arr vecarr;
+	bool addpath_capable = false;
+
+	if (DISABLE_BGP_ANNOUNCE)
+		return;
+
+	if (!subgrp)
+		return;
+
+	peer = SUBGRP_PEER(subgrp);
+	afi = SUBGRP_AFI(subgrp);
+	safi = SUBGRP_SAFI(subgrp);
+	bpacket_attr_vec_arr_reset(&vecarr);
+	addpath_capable = bgp_addpath_encode_tx(peer, afi, safi);
+
+	memset(&p, 0, sizeof(p));
+	p.family = afi2family(afi);
+	p.prefixlen = 0;
+
+	/* Logging the attribute. */
+	if (bgp_debug_update(NULL, &p, subgrp->update_group, 0)) {
+		char attrstr[BUFSIZ];
+		/* ' with addpath ID '          17
+		 * max strlen of uint32       + 10
+		 * +/- (just in case)         +  1
+		 * null terminator            +  1
+		 * ============================ 29 */
+		char tx_id_buf[30];
+
+		attrstr[0] = '\0';
+
+		bgp_dump_attr(attr, attrstr, sizeof(attrstr));
+
+		if (addpath_capable)
+			snprintf(tx_id_buf, sizeof(tx_id_buf),
+				 " with addpath ID %u",
+				 BGP_ADDPATH_TX_ID_FOR_DEFAULT_ORIGINATE);
+		else
+			tx_id_buf[0] = '\0';
+
+		zlog_debug("u%" PRIu64 ":s%" PRIu64 " send UPDATE %pFX%s %s",
+			   (SUBGRP_UPDGRP(subgrp))->id, subgrp->id, &p,
+			   tx_id_buf, attrstr);
+	}
+
+	s = stream_new(peer->max_packet_size);
+
+	/* Make BGP update packet. */
+	bgp_packet_set_marker(s, BGP_MSG_UPDATE);
+
+	/* Unfeasible Routes Length. */
+	stream_putw(s, 0);
+
+	/* Make place for total attribute length.  */
+	pos = stream_get_endp(s);
+	stream_putw(s, 0);
+	total_attr_len = bgp_packet_attribute(
+		NULL, peer, s, attr, &vecarr, &p, afi, safi, from, NULL, NULL,
+		0, addpath_capable, BGP_ADDPATH_TX_ID_FOR_DEFAULT_ORIGINATE);
+
+	/* Set Total Path Attribute Length. */
+	stream_putw_at(s, pos, total_attr_len);
+
+	/* NLRI set. */
+	if (p.family == AF_INET && safi == SAFI_UNICAST
+	    && !peer_cap_enhe(peer, afi, safi))
+		stream_put_prefix_addpath(
+			s, &p, addpath_capable,
+			BGP_ADDPATH_TX_ID_FOR_DEFAULT_ORIGINATE);
+
+	/* Set size. */
+	bgp_packet_set_size(s);
+
+	(void)bpacket_queue_add(SUBGRP_PKTQ(subgrp), s, &vecarr);
+	subgroup_trigger_write(subgrp);
+
+	if (!CHECK_FLAG(subgrp->sflags,
+			SUBGRP_STATUS_PEER_DEFAULT_ORIGINATED)) {
+		subgrp->scount++;
+		SET_FLAG(subgrp->sflags, SUBGRP_STATUS_PEER_DEFAULT_ORIGINATED);
+	}
+}
+
+void subgroup_default_withdraw_packet(struct update_subgroup *subgrp)
+{
+	struct peer *peer;
+	struct stream *s;
+	struct prefix p;
+	unsigned long attrlen_pos = 0;
+	unsigned long cp;
+	bgp_size_t unfeasible_len;
+	bgp_size_t total_attr_len = 0;
+	size_t mp_start = 0;
+	size_t mplen_pos = 0;
+	afi_t afi;
+	safi_t safi;
+	bool addpath_capable = false;
+
+	if (DISABLE_BGP_ANNOUNCE)
+		return;
+
+	peer = SUBGRP_PEER(subgrp);
+	afi = SUBGRP_AFI(subgrp);
+	safi = SUBGRP_SAFI(subgrp);
+	addpath_capable = bgp_addpath_encode_tx(peer, afi, safi);
+
+	memset(&p, 0, sizeof(p));
+	p.family = afi2family(afi);
+	p.prefixlen = 0;
+
+	if (bgp_debug_update(NULL, &p, subgrp->update_group, 0)) {
+		/* ' with addpath ID '          17
+		 * max strlen of uint32       + 10
+		 * +/- (just in case)         +  1
+		 * null terminator            +  1
+		 * ============================ 29 */
+		char tx_id_buf[30];
+
+		if (addpath_capable)
+			snprintf(tx_id_buf, sizeof(tx_id_buf),
+				 " with addpath ID %u",
+				 BGP_ADDPATH_TX_ID_FOR_DEFAULT_ORIGINATE);
+
+		zlog_debug("u%" PRIu64 ":s%" PRIu64
+			   " send UPDATE %pFX%s -- unreachable",
+			   (SUBGRP_UPDGRP(subgrp))->id, subgrp->id, &p,
+			   tx_id_buf);
+	}
+
+	s = stream_new(peer->max_packet_size);
+
+	/* Make BGP update packet. */
+	bgp_packet_set_marker(s, BGP_MSG_UPDATE);
+
+	/* Unfeasible Routes Length. */;
+	cp = stream_get_endp(s);
+	stream_putw(s, 0);
+
+	/* Withdrawn Routes. */
+	if (p.family == AF_INET && safi == SAFI_UNICAST
+	    && !peer_cap_enhe(peer, afi, safi)) {
+		stream_put_prefix_addpath(
+			s, &p, addpath_capable,
+			BGP_ADDPATH_TX_ID_FOR_DEFAULT_ORIGINATE);
+
+		unfeasible_len = stream_get_endp(s) - cp - 2;
+
+		/* Set unfeasible len.  */
+		stream_putw_at(s, cp, unfeasible_len);
+
+		/* Set total path attribute length. */
+		stream_putw(s, 0);
+	} else {
+		attrlen_pos = stream_get_endp(s);
+		stream_putw(s, 0);
+		mp_start = stream_get_endp(s);
+		mplen_pos = bgp_packet_mpunreach_start(s, afi, safi);
+		bgp_packet_mpunreach_prefix(
+			s, &p, afi, safi, NULL, NULL, 0, addpath_capable,
+			BGP_ADDPATH_TX_ID_FOR_DEFAULT_ORIGINATE, NULL);
+
+		/* Set the mp_unreach attr's length */
+		bgp_packet_mpunreach_end(s, mplen_pos);
+
+		/* Set total path attribute length. */
+		total_attr_len = stream_get_endp(s) - mp_start;
+		stream_putw_at(s, attrlen_pos, total_attr_len);
+	}
+
+	bgp_packet_set_size(s);
+
+	(void)bpacket_queue_add(SUBGRP_PKTQ(subgrp), s, NULL);
+	subgroup_trigger_write(subgrp);
+
+	if (CHECK_FLAG(subgrp->sflags, SUBGRP_STATUS_PEER_DEFAULT_ORIGINATED)) {
+		subgrp->scount--;
+		UNSET_FLAG(subgrp->sflags,
+			   SUBGRP_STATUS_PEER_DEFAULT_ORIGINATED);
+	}
+}
+
+static void
+bpacket_vec_arr_inherit_attr_flags(struct bpacket_attr_vec_arr *vecarr,
+				   enum bpacket_attr_vec_type type,
+				   struct attr *attr)
+{
+	if (CHECK_FLAG(attr->rmap_change_flags,
+		       BATTR_RMAP_NEXTHOP_PEER_ADDRESS))
+		SET_FLAG(vecarr->entries[BGP_ATTR_VEC_NH].flags,
+			 BPKT_ATTRVEC_FLAGS_RMAP_NH_PEER_ADDRESS);
+
+	if (CHECK_FLAG(attr->rmap_change_flags, BATTR_REFLECTED))
+		SET_FLAG(vecarr->entries[BGP_ATTR_VEC_NH].flags,
+			 BPKT_ATTRVEC_FLAGS_REFLECTED);
+
+	if (CHECK_FLAG(attr->rmap_change_flags, BATTR_RMAP_NEXTHOP_UNCHANGED))
+		SET_FLAG(vecarr->entries[BGP_ATTR_VEC_NH].flags,
+			 BPKT_ATTRVEC_FLAGS_RMAP_NH_UNCHANGED);
+
+	if (CHECK_FLAG(attr->rmap_change_flags, BATTR_RMAP_IPV4_NHOP_CHANGED))
+		SET_FLAG(vecarr->entries[BGP_ATTR_VEC_NH].flags,
+			 BPKT_ATTRVEC_FLAGS_RMAP_IPV4_NH_CHANGED);
+
+	if (CHECK_FLAG(attr->rmap_change_flags,
+		       BATTR_RMAP_IPV6_GLOBAL_NHOP_CHANGED))
+		SET_FLAG(vecarr->entries[BGP_ATTR_VEC_NH].flags,
+			 BPKT_ATTRVEC_FLAGS_RMAP_IPV6_GNH_CHANGED);
+
+	if (CHECK_FLAG(attr->rmap_change_flags,
+		       BATTR_RMAP_IPV6_LL_NHOP_CHANGED))
+		SET_FLAG(vecarr->entries[BGP_ATTR_VEC_NH].flags,
+			 BPKT_ATTRVEC_FLAGS_RMAP_IPV6_LNH_CHANGED);
+}
+
+/* Reset the Attributes vector array. The vector array is used to override
+ * certain output parameters in the packet for a particular peer
+ */
+void bpacket_attr_vec_arr_reset(struct bpacket_attr_vec_arr *vecarr)
+{
+	int i;
+
+	if (!vecarr)
+		return;
+
+	i = 0;
+	while (i < BGP_ATTR_VEC_MAX) {
+		vecarr->entries[i].flags = 0;
+		vecarr->entries[i].offset = 0;
+		i++;
+	}
+}
+
+/* Setup a particular node entry in the vecarr */
+void bpacket_attr_vec_arr_set_vec(struct bpacket_attr_vec_arr *vecarr,
+				  enum bpacket_attr_vec_type type,
+				  struct stream *s, struct attr *attr)
+{
+	if (!vecarr)
+		return;
+	assert(type < BGP_ATTR_VEC_MAX);
+
+	SET_FLAG(vecarr->entries[type].flags, BPKT_ATTRVEC_FLAGS_UPDATED);
+	vecarr->entries[type].offset = stream_get_endp(s);
+	if (attr)
+		bpacket_vec_arr_inherit_attr_flags(vecarr, type, attr);
+}