bgpd: Modify the BGP to zebra route announcement to support multipath
routes. Use a growable buffer (bgp_nexthop_buf) to collect nexthops
that are included in the announcement. Use the BGP_INFO_MULTIPATH_CHG
flag to trigger zebra announcement so zebra will be updated if the
multipath set changes. Display all multipath nexthops in
'debug bgp zebra' output.
* bgpd/bgp_main.c
* bgp_exit(): Free bgp_nexthop_buf when exiting
* bgpd/bgp_route.c
* bgp_process_rsclient(): Clear BGP_INFO_MULTIPATH_CHG after processing
* bgp_process_main(): Check BGP_INFO_MULTIPATH_CHG to trigger zebra
announcement and clear aftr processing
* bgpd/bgp_zebra.c
* bgp_nexthop_buf: Growable buffer used to collect nexthops for zebra
announcement
* bgp_zebra_announce(): Grow bgp_nexthop_buf if needed. Include
multipath count in zebra announcement and add all nexthops to
bgp_nexthop_buf. Pass bgp_nexthop_buf data to zebra announcement.
Added nexthops to debug output.
* bgp_zebra_init(): Initialize bgp_nexthop_buf at startup
* bgpd/bgp_zebra.h
* BGP_NEXTHOP_BUF_SIZE: Default initial bgp_nexthop_buf size has room
for 8 nexthops
diff --git a/bgpd/bgp_main.c b/bgpd/bgp_main.c
index 1a460c6..e5fa79d 100644
--- a/bgpd/bgp_main.c
+++ b/bgpd/bgp_main.c
@@ -35,6 +35,7 @@
#include "routemap.h"
#include "filter.h"
#include "plist.h"
+#include "stream.h"
#include "bgpd/bgpd.h"
#include "bgpd/bgp_attr.h"
@@ -47,6 +48,7 @@
#include "bgpd/bgp_clist.h"
#include "bgpd/bgp_debug.h"
#include "bgpd/bgp_filter.h"
+#include "bgpd/bgp_zebra.h"
/* bgpd options, we use GNU getopt library. */
static const struct option longopts[] =
@@ -293,6 +295,8 @@
zclient_free (zclient);
if (zlookup)
zclient_free (zlookup);
+ if (bgp_nexthop_buf)
+ stream_free (bgp_nexthop_buf);
/* reverse bgp_master_init */
if (master)
diff --git a/bgpd/bgp_route.c b/bgpd/bgp_route.c
index ec17dc6..f3e4622 100644
--- a/bgpd/bgp_route.c
+++ b/bgpd/bgp_route.c
@@ -1487,7 +1487,8 @@
{
bgp_info_set_flag (rn, new_select, BGP_INFO_SELECTED);
bgp_info_unset_flag (rn, new_select, BGP_INFO_ATTR_CHANGED);
- }
+ UNSET_FLAG (new_select->flags, BGP_INFO_MULTIPATH_CHG);
+ }
bgp_process_announce_selected (rsclient, new_select, rn,
afi, safi);
@@ -1501,6 +1502,7 @@
{
bgp_info_set_flag (rn, new_select, BGP_INFO_SELECTED);
bgp_info_unset_flag (rn, new_select, BGP_INFO_ATTR_CHANGED);
+ UNSET_FLAG (new_select->flags, BGP_INFO_MULTIPATH_CHG);
}
bgp_process_announce_selected (rsclient, new_select, rn, afi, safi);
}
@@ -1537,9 +1539,11 @@
{
if (! CHECK_FLAG (old_select->flags, BGP_INFO_ATTR_CHANGED))
{
- if (CHECK_FLAG (old_select->flags, BGP_INFO_IGP_CHANGED))
+ if (CHECK_FLAG (old_select->flags, BGP_INFO_IGP_CHANGED) ||
+ CHECK_FLAG (old_select->flags, BGP_INFO_MULTIPATH_CHG))
bgp_zebra_announce (p, old_select, bgp);
+ UNSET_FLAG (old_select->flags, BGP_INFO_MULTIPATH_CHG);
UNSET_FLAG (rn->flags, BGP_NODE_PROCESS_SCHEDULED);
return WQ_SUCCESS;
}
@@ -1551,6 +1555,7 @@
{
bgp_info_set_flag (rn, new_select, BGP_INFO_SELECTED);
bgp_info_unset_flag (rn, new_select, BGP_INFO_ATTR_CHANGED);
+ UNSET_FLAG (new_select->flags, BGP_INFO_MULTIPATH_CHG);
}
diff --git a/bgpd/bgp_zebra.c b/bgpd/bgp_zebra.c
index f3baeee..6c21230 100644
--- a/bgpd/bgp_zebra.c
+++ b/bgpd/bgp_zebra.c
@@ -37,11 +37,15 @@
#include "bgpd/bgp_zebra.h"
#include "bgpd/bgp_fsm.h"
#include "bgpd/bgp_debug.h"
+#include "bgpd/bgp_mpath.h"
/* All information about zebra. */
struct zclient *zclient = NULL;
struct in_addr router_id_zebra;
+/* Growable buffer for nexthops sent to zebra */
+struct stream *bgp_nexthop_buf = NULL;
+
/* Router-id update message from zebra. */
static int
bgp_router_id_update (int command, struct zclient *zclient, zebra_size_t length)
@@ -645,6 +649,8 @@
int flags;
u_char distance;
struct peer *peer;
+ struct bgp_info *mpinfo;
+ size_t oldsize, newsize;
if (zclient->sock < 0)
return;
@@ -665,6 +671,21 @@
|| CHECK_FLAG (peer->flags, PEER_FLAG_DISABLE_CONNECTED_CHECK))
SET_FLAG (flags, ZEBRA_FLAG_INTERNAL);
+ /* resize nexthop buffer size if necessary */
+ if ((oldsize = stream_get_size (bgp_nexthop_buf)) <
+ (sizeof (struct in_addr *) * (bgp_info_mpath_count (info) + 1)))
+ {
+ newsize = (sizeof (struct in_addr *) * (bgp_info_mpath_count (info) + 1));
+ newsize = stream_resize (bgp_nexthop_buf, newsize);
+ if (newsize == oldsize)
+ {
+ zlog_err ("can't resize nexthop buffer");
+ return;
+ }
+ }
+
+ stream_reset (bgp_nexthop_buf);
+
if (p->family == AF_INET)
{
struct zapi_ipv4 api;
@@ -672,12 +693,19 @@
api.flags = flags;
nexthop = &info->attr->nexthop;
+ stream_put (bgp_nexthop_buf, &nexthop, sizeof (struct in_addr *));
+ for (mpinfo = bgp_info_mpath_first (info); mpinfo;
+ mpinfo = bgp_info_mpath_next (mpinfo))
+ {
+ nexthop = &mpinfo->attr->nexthop;
+ stream_put (bgp_nexthop_buf, &nexthop, sizeof (struct in_addr *));
+ }
api.type = ZEBRA_ROUTE_BGP;
api.message = 0;
SET_FLAG (api.message, ZAPI_MESSAGE_NEXTHOP);
- api.nexthop_num = 1;
- api.nexthop = &nexthop;
+ api.nexthop_num = 1 + bgp_info_mpath_count (info);
+ api.nexthop = (struct in_addr **)STREAM_DATA (bgp_nexthop_buf);
api.ifindex_num = 0;
SET_FLAG (api.message, ZAPI_MESSAGE_METRIC);
api.metric = info->attr->med;
@@ -692,12 +720,18 @@
if (BGP_DEBUG(zebra, ZEBRA))
{
+ int i;
char buf[2][INET_ADDRSTRLEN];
- zlog_debug("Zebra send: IPv4 route add %s/%d nexthop %s metric %u",
+ zlog_debug("Zebra send: IPv4 route add %s/%d nexthop %s metric %u"
+ " count %d",
inet_ntop(AF_INET, &p->u.prefix4, buf[0], sizeof(buf[0])),
p->prefixlen,
- inet_ntop(AF_INET, nexthop, buf[1], sizeof(buf[1])),
- api.metric);
+ inet_ntop(AF_INET, api.nexthop[0], buf[1], sizeof(buf[1])),
+ api.metric, api.nexthop_num);
+ for (i = 1; i < api.nexthop_num; i++)
+ zlog_debug("Zebra send: IPv4 route add [nexthop %d] %s",
+ i, inet_ntop(AF_INET, api.nexthop[i], buf[1],
+ sizeof(buf[1])));
}
zapi_ipv4_route (ZEBRA_IPV4_ROUTE_ADD, zclient,
@@ -1043,4 +1077,6 @@
/* Interface related init. */
if_init ();
+
+ bgp_nexthop_buf = stream_new(BGP_NEXTHOP_BUF_SIZE);
}
diff --git a/bgpd/bgp_zebra.h b/bgpd/bgp_zebra.h
index 5172cb8..461255e 100644
--- a/bgpd/bgp_zebra.h
+++ b/bgpd/bgp_zebra.h
@@ -21,6 +21,10 @@
#ifndef _QUAGGA_BGP_ZEBRA_H
#define _QUAGGA_BGP_ZEBRA_H
+#define BGP_NEXTHOP_BUF_SIZE (8 * sizeof (struct in_addr *))
+
+extern struct stream *bgp_nexthop_buf;
+
extern void bgp_zebra_init (void);
extern int bgp_if_update_all (void);
extern int bgp_config_write_maxpaths (struct vty *, struct bgp *, afi_t,