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|
/* BGP Nexthop tracking
* Copyright (C) 2013 Cumulus Networks, Inc.
*
* 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 "command.h"
#include "thread.h"
#include "prefix.h"
#include "zclient.h"
#include "stream.h"
#include "network.h"
#include "log.h"
#include "memory.h"
#include "nexthop.h"
#include "vrf.h"
#include "filter.h"
#include "bgpd/bgpd.h"
#include "bgpd/bgp_table.h"
#include "bgpd/bgp_route.h"
#include "bgpd/bgp_attr.h"
#include "bgpd/bgp_nexthop.h"
#include "bgpd/bgp_debug.h"
#include "bgpd/bgp_errors.h"
#include "bgpd/bgp_nht.h"
#include "bgpd/bgp_fsm.h"
#include "bgpd/bgp_zebra.h"
#include "bgpd/bgp_flowspec_util.h"
#include "bgpd/bgp_evpn.h"
extern struct zclient *zclient;
static void register_zebra_rnh(struct bgp_nexthop_cache *bnc,
int is_bgp_static_route);
static void unregister_zebra_rnh(struct bgp_nexthop_cache *bnc,
int is_bgp_static_route);
static void evaluate_paths(struct bgp_nexthop_cache *bnc);
static int make_prefix(int afi, struct bgp_path_info *pi, struct prefix *p);
static int bgp_isvalid_nexthop(struct bgp_nexthop_cache *bnc)
{
return (bgp_zebra_num_connects() == 0
|| (bnc && CHECK_FLAG(bnc->flags, BGP_NEXTHOP_VALID)));
}
static int bgp_isvalid_labeled_nexthop(struct bgp_nexthop_cache *bnc)
{
return (bgp_zebra_num_connects() == 0
|| (bnc && CHECK_FLAG(bnc->flags, BGP_NEXTHOP_LABELED_VALID)));
}
static void bgp_unlink_nexthop_check(struct bgp_nexthop_cache *bnc)
{
if (LIST_EMPTY(&(bnc->paths)) && !bnc->nht_info) {
if (BGP_DEBUG(nht, NHT)) {
char buf[PREFIX2STR_BUFFER];
zlog_debug("bgp_unlink_nexthop: freeing bnc %s(%s)",
bnc_str(bnc, buf, PREFIX2STR_BUFFER),
bnc->bgp->name_pretty);
}
unregister_zebra_rnh(bnc,
CHECK_FLAG(bnc->flags, BGP_STATIC_ROUTE));
bgp_node_set_bgp_nexthop_info(bnc->node, NULL);
bgp_unlock_node(bnc->node);
bnc->node = NULL;
bnc_free(bnc);
}
}
void bgp_unlink_nexthop(struct bgp_path_info *path)
{
struct bgp_nexthop_cache *bnc = path->nexthop;
if (!bnc)
return;
path_nh_map(path, NULL, false);
bgp_unlink_nexthop_check(bnc);
}
void bgp_unlink_nexthop_by_peer(struct peer *peer)
{
struct prefix p;
struct bgp_node *rn;
struct bgp_nexthop_cache *bnc;
afi_t afi = family2afi(peer->su.sa.sa_family);
if (!sockunion2hostprefix(&peer->su, &p))
return;
rn = bgp_node_get(peer->bgp->nexthop_cache_table[afi], &p);
bnc = bgp_node_get_bgp_nexthop_info(rn);
if (!bnc)
return;
/* cleanup the peer reference */
bnc->nht_info = NULL;
bgp_unlink_nexthop_check(bnc);
}
/*
* A route and its nexthop might belong to different VRFs. Therefore,
* we need both the bgp_route and bgp_nexthop pointers.
*/
int bgp_find_or_add_nexthop(struct bgp *bgp_route, struct bgp *bgp_nexthop,
afi_t afi, struct bgp_path_info *pi,
struct peer *peer, int connected)
{
struct bgp_node *rn;
struct bgp_nexthop_cache *bnc;
struct prefix p;
int is_bgp_static_route = 0;
if (pi) {
is_bgp_static_route = ((pi->type == ZEBRA_ROUTE_BGP)
&& (pi->sub_type == BGP_ROUTE_STATIC))
? 1
: 0;
/* Since Extended Next-hop Encoding (RFC5549) support, we want
to derive
address-family from the next-hop. */
if (!is_bgp_static_route)
afi = BGP_ATTR_NEXTHOP_AFI_IP6(pi->attr) ? AFI_IP6
: AFI_IP;
/* This will return true if the global IPv6 NH is a link local
* addr */
if (make_prefix(afi, pi, &p) < 0)
return 1;
} else if (peer) {
if (!sockunion2hostprefix(&peer->su, &p)) {
if (BGP_DEBUG(nht, NHT)) {
zlog_debug(
"%s: Attempting to register with unknown AFI %d (not %d or %d)",
__FUNCTION__, afi, AFI_IP, AFI_IP6);
}
return 0;
}
} else
return 0;
if (is_bgp_static_route)
rn = bgp_node_get(bgp_nexthop->import_check_table[afi], &p);
else
rn = bgp_node_get(bgp_nexthop->nexthop_cache_table[afi], &p);
bnc = bgp_node_get_bgp_nexthop_info(rn);
if (!bnc) {
bnc = bnc_new();
bgp_node_set_bgp_nexthop_info(rn, bnc);
bnc->node = rn;
bnc->bgp = bgp_nexthop;
bgp_lock_node(rn);
if (BGP_DEBUG(nht, NHT)) {
char buf[PREFIX2STR_BUFFER];
zlog_debug("Allocated bnc %s(%s) peer %p",
bnc_str(bnc, buf, PREFIX2STR_BUFFER),
bnc->bgp->name_pretty, peer);
}
}
bgp_unlock_node(rn);
if (is_bgp_static_route) {
SET_FLAG(bnc->flags, BGP_STATIC_ROUTE);
/* If we're toggling the type, re-register */
if ((bgp_flag_check(bgp_route, BGP_FLAG_IMPORT_CHECK))
&& !CHECK_FLAG(bnc->flags, BGP_STATIC_ROUTE_EXACT_MATCH)) {
SET_FLAG(bnc->flags, BGP_STATIC_ROUTE_EXACT_MATCH);
UNSET_FLAG(bnc->flags, BGP_NEXTHOP_REGISTERED);
UNSET_FLAG(bnc->flags, BGP_NEXTHOP_VALID);
} else if ((!bgp_flag_check(bgp_route, BGP_FLAG_IMPORT_CHECK))
&& CHECK_FLAG(bnc->flags,
BGP_STATIC_ROUTE_EXACT_MATCH)) {
UNSET_FLAG(bnc->flags, BGP_STATIC_ROUTE_EXACT_MATCH);
UNSET_FLAG(bnc->flags, BGP_NEXTHOP_REGISTERED);
UNSET_FLAG(bnc->flags, BGP_NEXTHOP_VALID);
}
}
/* When nexthop is already known, but now requires 'connected'
* resolution,
* re-register it. The reverse scenario where the nexthop currently
* requires
* 'connected' resolution does not need a re-register (i.e., we treat
* 'connected-required' as an override) except in the scenario where
* this
* is actually a case of tracking a peer for connectivity (e.g., after
* disable connected-check).
* NOTE: We don't track the number of paths separately for 'connected-
* required' vs 'connected-not-required' as this change is not a common
* scenario.
*/
else if (connected && !CHECK_FLAG(bnc->flags, BGP_NEXTHOP_CONNECTED)) {
SET_FLAG(bnc->flags, BGP_NEXTHOP_CONNECTED);
UNSET_FLAG(bnc->flags, BGP_NEXTHOP_REGISTERED);
UNSET_FLAG(bnc->flags, BGP_NEXTHOP_VALID);
} else if (peer && !connected
&& CHECK_FLAG(bnc->flags, BGP_NEXTHOP_CONNECTED)) {
UNSET_FLAG(bnc->flags, BGP_NEXTHOP_CONNECTED);
UNSET_FLAG(bnc->flags, BGP_NEXTHOP_REGISTERED);
UNSET_FLAG(bnc->flags, BGP_NEXTHOP_VALID);
}
if (bgp_route->inst_type == BGP_INSTANCE_TYPE_VIEW) {
SET_FLAG(bnc->flags, BGP_NEXTHOP_REGISTERED);
SET_FLAG(bnc->flags, BGP_NEXTHOP_VALID);
} else if (!CHECK_FLAG(bnc->flags, BGP_NEXTHOP_REGISTERED) &&
!is_default_host_route(&bnc->node->p))
register_zebra_rnh(bnc, is_bgp_static_route);
if (pi && pi->nexthop != bnc) {
/* Unlink from existing nexthop cache, if any. This will also
* free
* the nexthop cache entry, if appropriate.
*/
bgp_unlink_nexthop(pi);
/* updates NHT pi list reference */
path_nh_map(pi, bnc, true);
if (CHECK_FLAG(bnc->flags, BGP_NEXTHOP_VALID) && bnc->metric)
(bgp_path_info_extra_get(pi))->igpmetric = bnc->metric;
else if (pi->extra)
pi->extra->igpmetric = 0;
} else if (peer)
bnc->nht_info = (void *)peer; /* NHT peer reference */
/*
* We are cheating here. Views have no associated underlying
* ability to detect nexthops. So when we have a view
* just tell everyone the nexthop is valid
*/
if (bgp_route->inst_type == BGP_INSTANCE_TYPE_VIEW)
return 1;
else
return (bgp_isvalid_nexthop(bnc));
}
void bgp_delete_connected_nexthop(afi_t afi, struct peer *peer)
{
struct bgp_node *rn;
struct bgp_nexthop_cache *bnc;
struct prefix p;
if (!peer)
return;
if (!sockunion2hostprefix(&peer->su, &p))
return;
rn = bgp_node_lookup(
peer->bgp->nexthop_cache_table[family2afi(p.family)], &p);
if (!rn) {
if (BGP_DEBUG(nht, NHT))
zlog_debug(
"Cannot find connected NHT node for peer %s(%s)",
peer->host, peer->bgp->name_pretty);
return;
}
bnc = bgp_node_get_bgp_nexthop_info(rn);
if (!bnc) {
if (BGP_DEBUG(nht, NHT))
zlog_debug(
"Cannot find connected NHT node for peer %s(%s) on route_node as expected",
peer->host, peer->bgp->name_pretty);
bgp_unlock_node(rn);
return;
}
bgp_unlock_node(rn);
if (bnc->nht_info != peer) {
if (BGP_DEBUG(nht, NHT))
zlog_debug(
"Connected NHT %p node for peer %s(%s) points to %p",
bnc, peer->host, bnc->bgp->name_pretty,
bnc->nht_info);
return;
}
bnc->nht_info = NULL;
if (LIST_EMPTY(&(bnc->paths))) {
if (BGP_DEBUG(nht, NHT))
zlog_debug(
"Freeing connected NHT node %p for peer %s(%s)",
bnc, peer->host, bnc->bgp->name_pretty);
unregister_zebra_rnh(bnc, 0);
bgp_node_set_bgp_nexthop_info(bnc->node, NULL);
bgp_unlock_node(bnc->node);
bnc_free(bnc);
}
}
void bgp_parse_nexthop_update(int command, vrf_id_t vrf_id)
{
struct bgp_node *rn = NULL;
struct bgp_nexthop_cache *bnc;
struct nexthop *nexthop;
struct nexthop *oldnh;
struct nexthop *nhlist_head = NULL;
struct nexthop *nhlist_tail = NULL;
int i;
struct bgp *bgp;
struct zapi_route nhr;
bgp = bgp_lookup_by_vrf_id(vrf_id);
if (!bgp) {
flog_err(
EC_BGP_NH_UPD,
"parse nexthop update: instance not found for vrf_id %u",
vrf_id);
return;
}
if (!zapi_nexthop_update_decode(zclient->ibuf, &nhr)) {
if (BGP_DEBUG(nht, NHT))
zlog_debug("%s[%s]: Failure to decode nexthop update",
__PRETTY_FUNCTION__, bgp->name_pretty);
return;
}
if (command == ZEBRA_NEXTHOP_UPDATE)
rn = bgp_node_lookup(
bgp->nexthop_cache_table[family2afi(nhr.prefix.family)],
&nhr.prefix);
else if (command == ZEBRA_IMPORT_CHECK_UPDATE)
rn = bgp_node_lookup(
bgp->import_check_table[family2afi(nhr.prefix.family)],
&nhr.prefix);
if (!rn) {
if (BGP_DEBUG(nht, NHT)) {
char buf[PREFIX2STR_BUFFER];
prefix2str(&nhr.prefix, buf, sizeof(buf));
zlog_debug("parse nexthop update(%s(%s)): rn not found",
buf, bgp->name_pretty);
}
return;
}
bnc = bgp_node_get_bgp_nexthop_info(rn);
if (!bnc) {
if (BGP_DEBUG(nht, NHT)) {
char buf[PREFIX2STR_BUFFER];
prefix2str(&nhr.prefix, buf, sizeof(buf));
zlog_debug(
"parse nexthop update(%s(%s)): bnc node info not found",
buf, bgp->name_pretty);
}
bgp_unlock_node(rn);
return;
}
bgp_unlock_node(rn);
bnc->last_update = bgp_clock();
bnc->change_flags = 0;
/* debug print the input */
if (BGP_DEBUG(nht, NHT)) {
char buf[PREFIX2STR_BUFFER];
prefix2str(&nhr.prefix, buf, sizeof(buf));
zlog_debug(
"%s(%u): Rcvd NH update %s - metric %d/%d #nhops %d/%d flags 0x%x",
bnc->bgp->name_pretty, vrf_id, buf, nhr.metric,
bnc->metric, nhr.nexthop_num, bnc->nexthop_num,
bnc->flags);
}
if (nhr.metric != bnc->metric)
bnc->change_flags |= BGP_NEXTHOP_METRIC_CHANGED;
if (nhr.nexthop_num != bnc->nexthop_num)
bnc->change_flags |= BGP_NEXTHOP_CHANGED;
if (nhr.nexthop_num) {
struct peer *peer = bnc->nht_info;
/* notify bgp fsm if nbr ip goes from invalid->valid */
if (!bnc->nexthop_num)
UNSET_FLAG(bnc->flags, BGP_NEXTHOP_PEER_NOTIFIED);
bnc->flags |= BGP_NEXTHOP_VALID;
bnc->metric = nhr.metric;
bnc->nexthop_num = nhr.nexthop_num;
bnc->flags &= ~BGP_NEXTHOP_LABELED_VALID; /* check below */
for (i = 0; i < nhr.nexthop_num; i++) {
int num_labels = 0;
nexthop = nexthop_from_zapi_nexthop(&nhr.nexthops[i]);
/*
* Turn on RA for the v6 nexthops
* we receive from bgp. This is to allow us
* to work with v4 routing over v6 nexthops
*/
if (peer && !peer->ifp
&& CHECK_FLAG(peer->flags,
PEER_FLAG_CAPABILITY_ENHE)
&& nhr.prefix.family == AF_INET6) {
struct interface *ifp;
ifp = if_lookup_by_index(nexthop->ifindex,
nexthop->vrf_id);
zclient_send_interface_radv_req(
zclient, nexthop->vrf_id, ifp, true,
BGP_UNNUM_DEFAULT_RA_INTERVAL);
}
/* There is at least one label-switched path */
if (nexthop->nh_label &&
nexthop->nh_label->num_labels) {
bnc->flags |= BGP_NEXTHOP_LABELED_VALID;
num_labels = nexthop->nh_label->num_labels;
}
if (BGP_DEBUG(nht, NHT)) {
char buf[NEXTHOP_STRLEN];
zlog_debug(
" nhop via %s (%d labels)",
nexthop2str(nexthop, buf, sizeof(buf)),
num_labels);
}
if (nhlist_tail) {
nhlist_tail->next = nexthop;
nhlist_tail = nexthop;
} else {
nhlist_tail = nexthop;
nhlist_head = nexthop;
}
/* No need to evaluate the nexthop if we have already
* determined
* that there has been a change.
*/
if (bnc->change_flags & BGP_NEXTHOP_CHANGED)
continue;
for (oldnh = bnc->nexthop; oldnh; oldnh = oldnh->next)
if (nexthop_same(oldnh, nexthop))
break;
if (!oldnh)
bnc->change_flags |= BGP_NEXTHOP_CHANGED;
}
bnc_nexthop_free(bnc);
bnc->nexthop = nhlist_head;
} else {
bnc->flags &= ~BGP_NEXTHOP_VALID;
bnc->nexthop_num = nhr.nexthop_num;
/* notify bgp fsm if nbr ip goes from valid->invalid */
UNSET_FLAG(bnc->flags, BGP_NEXTHOP_PEER_NOTIFIED);
bnc_nexthop_free(bnc);
bnc->nexthop = NULL;
}
evaluate_paths(bnc);
}
/*
* Cleanup nexthop registration and status information for BGP nexthops
* pertaining to this VRF. This is invoked upon VRF deletion.
*/
void bgp_cleanup_nexthops(struct bgp *bgp)
{
afi_t afi;
struct bgp_node *rn;
struct bgp_nexthop_cache *bnc;
for (afi = AFI_IP; afi < AFI_MAX; afi++) {
if (!bgp->nexthop_cache_table[afi])
continue;
for (rn = bgp_table_top(bgp->nexthop_cache_table[afi]); rn;
rn = bgp_route_next(rn)) {
bnc = bgp_node_get_bgp_nexthop_info(rn);
if (!bnc)
continue;
/* Clear relevant flags. */
UNSET_FLAG(bnc->flags, BGP_NEXTHOP_VALID);
UNSET_FLAG(bnc->flags, BGP_NEXTHOP_REGISTERED);
UNSET_FLAG(bnc->flags, BGP_NEXTHOP_PEER_NOTIFIED);
}
}
}
/**
* make_prefix - make a prefix structure from the path (essentially
* path's node.
*/
static int make_prefix(int afi, struct bgp_path_info *pi, struct prefix *p)
{
int is_bgp_static = ((pi->type == ZEBRA_ROUTE_BGP)
&& (pi->sub_type == BGP_ROUTE_STATIC))
? 1
: 0;
struct bgp_node *net = pi->net;
struct prefix *p_orig = &net->p;
if (p_orig->family == AF_FLOWSPEC) {
if (!pi->peer)
return -1;
return bgp_flowspec_get_first_nh(pi->peer->bgp,
pi, p);
}
memset(p, 0, sizeof(struct prefix));
switch (afi) {
case AFI_IP:
p->family = AF_INET;
if (is_bgp_static) {
p->u.prefix4 = pi->net->p.u.prefix4;
p->prefixlen = pi->net->p.prefixlen;
} else {
p->u.prefix4 = pi->attr->nexthop;
p->prefixlen = IPV4_MAX_BITLEN;
}
break;
case AFI_IP6:
p->family = AF_INET6;
if (is_bgp_static) {
p->u.prefix6 = pi->net->p.u.prefix6;
p->prefixlen = pi->net->p.prefixlen;
} else {
p->u.prefix6 = pi->attr->mp_nexthop_global;
p->prefixlen = IPV6_MAX_BITLEN;
}
break;
default:
if (BGP_DEBUG(nht, NHT)) {
zlog_debug(
"%s: Attempting to make prefix with unknown AFI %d (not %d or %d)",
__FUNCTION__, afi, AFI_IP, AFI_IP6);
}
break;
}
return 0;
}
/**
* sendmsg_zebra_rnh -- Format and send a nexthop register/Unregister
* command to Zebra.
* ARGUMENTS:
* struct bgp_nexthop_cache *bnc -- the nexthop structure.
* int command -- command to send to zebra
* RETURNS:
* void.
*/
static void sendmsg_zebra_rnh(struct bgp_nexthop_cache *bnc, int command)
{
struct prefix *p;
bool exact_match = false;
int ret;
if (!zclient)
return;
/* Don't try to register if Zebra doesn't know of this instance. */
if (!IS_BGP_INST_KNOWN_TO_ZEBRA(bnc->bgp)) {
if (BGP_DEBUG(zebra, ZEBRA))
zlog_debug("%s: No zebra instance to talk to, not installing NHT entry",
__PRETTY_FUNCTION__);
return;
}
if (!bgp_zebra_num_connects()) {
if (BGP_DEBUG(zebra, ZEBRA))
zlog_debug("%s: We have not connected yet, cannot send nexthops",
__PRETTY_FUNCTION__);
}
p = &(bnc->node->p);
if ((command == ZEBRA_NEXTHOP_REGISTER
|| command == ZEBRA_IMPORT_ROUTE_REGISTER)
&& (CHECK_FLAG(bnc->flags, BGP_NEXTHOP_CONNECTED)
|| CHECK_FLAG(bnc->flags, BGP_STATIC_ROUTE_EXACT_MATCH)))
exact_match = true;
if (BGP_DEBUG(zebra, ZEBRA)) {
char buf[PREFIX2STR_BUFFER];
prefix2str(p, buf, PREFIX2STR_BUFFER);
zlog_debug("%s: sending cmd %s for %s (vrf %s)",
__func__, zserv_command_string(command), buf,
bnc->bgp->name_pretty);
}
ret = zclient_send_rnh(zclient, command, p, exact_match,
bnc->bgp->vrf_id);
/* TBD: handle the failure */
if (ret < 0)
flog_warn(EC_BGP_ZEBRA_SEND,
"sendmsg_nexthop: zclient_send_message() failed");
if ((command == ZEBRA_NEXTHOP_REGISTER)
|| (command == ZEBRA_IMPORT_ROUTE_REGISTER))
SET_FLAG(bnc->flags, BGP_NEXTHOP_REGISTERED);
else if ((command == ZEBRA_NEXTHOP_UNREGISTER)
|| (command == ZEBRA_IMPORT_ROUTE_UNREGISTER))
UNSET_FLAG(bnc->flags, BGP_NEXTHOP_REGISTERED);
return;
}
/**
* register_zebra_rnh - register a NH/route with Zebra for notification
* when the route or the route to the nexthop changes.
* ARGUMENTS:
* struct bgp_nexthop_cache *bnc
* RETURNS:
* void.
*/
static void register_zebra_rnh(struct bgp_nexthop_cache *bnc,
int is_bgp_import_route)
{
/* Check if we have already registered */
if (bnc->flags & BGP_NEXTHOP_REGISTERED)
return;
if (is_bgp_import_route)
sendmsg_zebra_rnh(bnc, ZEBRA_IMPORT_ROUTE_REGISTER);
else
sendmsg_zebra_rnh(bnc, ZEBRA_NEXTHOP_REGISTER);
}
/**
* unregister_zebra_rnh -- Unregister the route/nexthop from Zebra.
* ARGUMENTS:
* struct bgp_nexthop_cache *bnc
* RETURNS:
* void.
*/
static void unregister_zebra_rnh(struct bgp_nexthop_cache *bnc,
int is_bgp_import_route)
{
/* Check if we have already registered */
if (!CHECK_FLAG(bnc->flags, BGP_NEXTHOP_REGISTERED))
return;
if (is_bgp_import_route)
sendmsg_zebra_rnh(bnc, ZEBRA_IMPORT_ROUTE_UNREGISTER);
else
sendmsg_zebra_rnh(bnc, ZEBRA_NEXTHOP_UNREGISTER);
}
/**
* evaluate_paths - Evaluate the paths/nets associated with a nexthop.
* ARGUMENTS:
* struct bgp_nexthop_cache *bnc -- the nexthop structure.
* RETURNS:
* void.
*/
static void evaluate_paths(struct bgp_nexthop_cache *bnc)
{
struct bgp_node *rn;
struct bgp_path_info *path;
int afi;
struct peer *peer = (struct peer *)bnc->nht_info;
struct bgp_table *table;
safi_t safi;
struct bgp *bgp_path;
if (BGP_DEBUG(nht, NHT)) {
char buf[PREFIX2STR_BUFFER];
bnc_str(bnc, buf, PREFIX2STR_BUFFER);
zlog_debug(
"NH update for %s(%s) - flags 0x%x chgflags 0x%x - evaluate paths",
buf, bnc->bgp->name_pretty, bnc->flags,
bnc->change_flags);
}
LIST_FOREACH (path, &(bnc->paths), nh_thread) {
if (!(path->type == ZEBRA_ROUTE_BGP
&& ((path->sub_type == BGP_ROUTE_NORMAL)
|| (path->sub_type == BGP_ROUTE_STATIC)
|| (path->sub_type == BGP_ROUTE_IMPORTED))))
continue;
rn = path->net;
assert(rn && bgp_node_table(rn));
afi = family2afi(rn->p.family);
table = bgp_node_table(rn);
safi = table->safi;
/*
* handle routes from other VRFs (they can have a
* nexthop in THIS VRF). bgp_path is the bgp instance
* that owns the route referencing this nexthop.
*/
bgp_path = table->bgp;
/*
* Path becomes valid/invalid depending on whether the nexthop
* reachable/unreachable.
*
* In case of unicast routes that were imported from vpn
* and that have labels, they are valid only if there are
* nexthops with labels
*/
int bnc_is_valid_nexthop = 0;
if (safi == SAFI_UNICAST &&
path->sub_type == BGP_ROUTE_IMPORTED &&
path->extra &&
path->extra->num_labels) {
bnc_is_valid_nexthop =
bgp_isvalid_labeled_nexthop(bnc) ? 1 : 0;
} else {
bnc_is_valid_nexthop =
bgp_isvalid_nexthop(bnc) ? 1 : 0;
}
if (BGP_DEBUG(nht, NHT)) {
char buf[PREFIX_STRLEN];
prefix2str(&rn->p, buf, PREFIX_STRLEN);
zlog_debug("%s: prefix %s (vrf %s) %svalid",
__func__, buf, bgp_path->name,
(bnc_is_valid_nexthop ? "" : "not "));
}
if ((CHECK_FLAG(path->flags, BGP_PATH_VALID) ? 1 : 0)
!= bnc_is_valid_nexthop) {
if (CHECK_FLAG(path->flags, BGP_PATH_VALID)) {
bgp_aggregate_decrement(bgp_path, &rn->p,
path, afi, safi);
bgp_path_info_unset_flag(rn, path,
BGP_PATH_VALID);
} else {
bgp_path_info_set_flag(rn, path,
BGP_PATH_VALID);
bgp_aggregate_increment(bgp_path, &rn->p,
path, afi, safi);
}
}
/* Copy the metric to the path. Will be used for bestpath
* computation */
if (bgp_isvalid_nexthop(bnc) && bnc->metric)
(bgp_path_info_extra_get(path))->igpmetric =
bnc->metric;
else if (path->extra)
path->extra->igpmetric = 0;
if (CHECK_FLAG(bnc->change_flags, BGP_NEXTHOP_METRIC_CHANGED)
|| CHECK_FLAG(bnc->change_flags, BGP_NEXTHOP_CHANGED))
SET_FLAG(path->flags, BGP_PATH_IGP_CHANGED);
if (safi == SAFI_EVPN &&
bgp_evpn_is_prefix_nht_supported(&rn->p)) {
if (CHECK_FLAG(path->flags, BGP_PATH_VALID))
bgp_evpn_import_route(bgp_path, afi, safi,
&rn->p, path);
else
bgp_evpn_unimport_route(bgp_path, afi, safi,
&rn->p, path);
}
bgp_process(bgp_path, rn, afi, safi);
}
if (peer && !CHECK_FLAG(bnc->flags, BGP_NEXTHOP_PEER_NOTIFIED)) {
if (BGP_DEBUG(nht, NHT))
zlog_debug("%s: Updating peer (%s(%s)) status with NHT",
__FUNCTION__, peer->host,
peer->bgp->name_pretty);
bgp_fsm_event_update(peer, bgp_isvalid_nexthop(bnc));
SET_FLAG(bnc->flags, BGP_NEXTHOP_PEER_NOTIFIED);
}
RESET_FLAG(bnc->change_flags);
}
/**
* path_nh_map - make or break path-to-nexthop association.
* ARGUMENTS:
* path - pointer to the path structure
* bnc - pointer to the nexthop structure
* make - if set, make the association. if unset, just break the existing
* association.
*/
void path_nh_map(struct bgp_path_info *path, struct bgp_nexthop_cache *bnc,
bool make)
{
if (path->nexthop) {
LIST_REMOVE(path, nh_thread);
path->nexthop->path_count--;
path->nexthop = NULL;
}
if (make) {
LIST_INSERT_HEAD(&(bnc->paths), path, nh_thread);
path->nexthop = bnc;
path->nexthop->path_count++;
}
}
/*
* This function is called to register nexthops to zebra
* as that we may have tried to install the nexthops
* before we actually have a zebra connection
*/
void bgp_nht_register_nexthops(struct bgp *bgp)
{
struct bgp_node *rn;
struct bgp_nexthop_cache *bnc;
afi_t afi;
for (afi = AFI_IP; afi < AFI_MAX; afi++) {
if (!bgp->nexthop_cache_table[afi])
continue;
for (rn = bgp_table_top(bgp->nexthop_cache_table[afi]); rn;
rn = bgp_route_next(rn)) {
bnc = bgp_node_get_bgp_nexthop_info(rn);
if (!bnc)
continue;
register_zebra_rnh(bnc, 0);
}
}
}
void bgp_nht_register_enhe_capability_interfaces(struct peer *peer)
{
struct bgp *bgp;
struct bgp_node *rn;
struct bgp_nexthop_cache *bnc;
struct nexthop *nhop;
struct interface *ifp;
struct prefix p;
if (peer->ifp)
return;
bgp = peer->bgp;
if (!bgp->nexthop_cache_table[AFI_IP6])
return;
if (!sockunion2hostprefix(&peer->su, &p)) {
if (BGP_DEBUG(nht, NHT))
zlog_debug("%s: Unable to convert prefix to sockunion",
__PRETTY_FUNCTION__);
return;
}
if (p.family != AF_INET6)
return;
rn = bgp_node_lookup(bgp->nexthop_cache_table[AFI_IP6], &p);
if (!rn)
return;
bnc = bgp_node_get_bgp_nexthop_info(rn);
if (!bnc)
return;
if (peer != bnc->nht_info)
return;
for (nhop = bnc->nexthop; nhop; nhop = nhop->next) {
ifp = if_lookup_by_index(nhop->ifindex,
nhop->vrf_id);
zclient_send_interface_radv_req(zclient,
nhop->vrf_id,
ifp, true,
BGP_UNNUM_DEFAULT_RA_INTERVAL);
}
}
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