bgpd: Enable support for BGP IPV6 multipath.
This commit adds these two commands:
maximum-paths <1-MULTIPATH_NUM>
maximum-paths ibgp <1-MULTIPATH_NUM>
under address-family ipv6 mode. In addition adding the ability
to pass multiple paths down into zebra from bgp.
Signed-off-by: Ayan Banerjee <ayan@cumulusnetworks.com>
Signed-off-by: Dinesh G Dutt <ddutt@cumulusnetworks.com>
Reviewed-by: Scott Feldman <sfeldma@cumulusnetworks.com>
diff --git a/bgpd/bgp_zebra.c b/bgpd/bgp_zebra.c
index 85380f0..583604a 100644
--- a/bgpd/bgp_zebra.c
+++ b/bgpd/bgp_zebra.c
@@ -46,6 +46,7 @@
/* Growable buffer for nexthops sent to zebra */
struct stream *bgp_nexthop_buf = NULL;
+struct stream *bgp_ifindices_buf = NULL;
/* Router-id update message from zebra. */
static int
@@ -662,6 +663,7 @@
struct peer *peer;
struct bgp_info *mpinfo;
size_t oldsize, newsize;
+ u_int32_t nhcount;
if (zclient->sock < 0)
return;
@@ -682,26 +684,27 @@
|| 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);
+ nhcount = 1 + bgp_info_mpath_count (info);
if (p->family == AF_INET)
{
struct zapi_ipv4 api;
struct in_addr *nexthop;
+ /* resize nexthop buffer size if necessary */
+ if ((oldsize = stream_get_size (bgp_nexthop_buf)) <
+ (sizeof (struct in_addr *) * nhcount))
+ {
+ newsize = (sizeof (struct in_addr *) * nhcount);
+ newsize = stream_resize (bgp_nexthop_buf, newsize);
+ if (newsize == oldsize)
+ {
+ zlog_err ("can't resize nexthop buffer");
+ return;
+ }
+ }
+ stream_reset (bgp_nexthop_buf);
+
api.vrf_id = VRF_DEFAULT;
api.flags = flags;
nexthop = &info->attr->nexthop;
@@ -717,7 +720,7 @@
api.message = 0;
api.safi = safi;
SET_FLAG (api.message, ZAPI_MESSAGE_NEXTHOP);
- api.nexthop_num = 1 + bgp_info_mpath_count (info);
+ api.nexthop_num = nhcount;
api.nexthop = (struct in_addr **)STREAM_DATA (bgp_nexthop_buf);
api.ifindex_num = 0;
SET_FLAG (api.message, ZAPI_MESSAGE_METRIC);
@@ -757,10 +760,39 @@
ifindex_t ifindex;
struct in6_addr *nexthop;
struct zapi_ipv6 api;
+ int valid_nh_count = 0;
+
+ /* resize nexthop buffer size if necessary */
+ if ((oldsize = stream_get_size (bgp_nexthop_buf)) <
+ (sizeof (struct in6_addr *) * nhcount))
+ {
+ newsize = (sizeof (struct in6_addr *) * nhcount);
+ newsize = stream_resize (bgp_nexthop_buf, newsize);
+ if (newsize == oldsize)
+ {
+ zlog_err ("can't resize nexthop buffer");
+ return;
+ }
+ }
+ stream_reset (bgp_nexthop_buf);
+
+ /* resize ifindices buffer size if necessary */
+ if ((oldsize = stream_get_size (bgp_ifindices_buf)) <
+ (sizeof (unsigned int) * nhcount))
+ {
+ newsize = (sizeof (unsigned int) * nhcount);
+ newsize = stream_resize (bgp_ifindices_buf, newsize);
+ if (newsize == oldsize)
+ {
+ zlog_err ("can't resize nexthop buffer");
+ return;
+ }
+ }
+ stream_reset (bgp_ifindices_buf);
ifindex = 0;
nexthop = NULL;
-
+
assert (info->attr->extra);
/* Only global address nexthop exists. */
@@ -791,6 +823,62 @@
else if (info->peer->nexthop.ifp)
ifindex = info->peer->nexthop.ifp->ifindex;
}
+ stream_put (bgp_nexthop_buf, &nexthop, sizeof (struct in6_addr *));
+ stream_put (bgp_ifindices_buf, &ifindex, sizeof (unsigned int));
+ valid_nh_count++;
+
+ for (mpinfo = bgp_info_mpath_first (info); mpinfo;
+ mpinfo = bgp_info_mpath_next (mpinfo))
+ {
+ /* Only global address nexthop exists. */
+ if (mpinfo->attr->extra->mp_nexthop_len == 16)
+ {
+ nexthop = &mpinfo->attr->extra->mp_nexthop_global;
+ }
+ /* If both global and link-local address present. */
+ if (mpinfo->attr->extra->mp_nexthop_len == 32)
+ {
+ /* Workaround for Cisco's nexthop bug. */
+ if (IN6_IS_ADDR_UNSPECIFIED (&mpinfo->attr->extra->mp_nexthop_global)
+ && mpinfo->peer->su_remote->sa.sa_family == AF_INET6)
+ {
+ nexthop = &mpinfo->peer->su_remote->sin6.sin6_addr;
+ }
+ else
+ {
+ nexthop = &mpinfo->attr->extra->mp_nexthop_local;
+ }
+
+ if (mpinfo->peer->nexthop.ifp)
+ {
+ ifindex = mpinfo->peer->nexthop.ifp->ifindex;
+ }
+ }
+ if (nexthop == NULL)
+ {
+ continue;
+ }
+
+ if (IN6_IS_ADDR_LINKLOCAL (nexthop) && ! ifindex)
+ {
+ if (mpinfo->peer->ifname)
+ {
+ ifindex = if_nametoindex (mpinfo->peer->ifname);
+ }
+ else if (mpinfo->peer->nexthop.ifp)
+ {
+ ifindex = mpinfo->peer->nexthop.ifp->ifindex;
+ }
+ }
+ if (ifindex == 0)
+ {
+ continue;
+ }
+
+ stream_put (bgp_nexthop_buf, &nexthop, sizeof (struct in6_addr *));
+ stream_put (bgp_ifindices_buf, &ifindex, sizeof (unsigned int));
+ valid_nh_count++;
+ }
/* Make Zebra API structure. */
api.vrf_id = VRF_DEFAULT;
@@ -799,11 +887,11 @@
api.message = 0;
api.safi = safi;
SET_FLAG (api.message, ZAPI_MESSAGE_NEXTHOP);
- api.nexthop_num = 1;
- api.nexthop = &nexthop;
+ api.nexthop_num = valid_nh_count;
+ api.nexthop = (struct in6_addr **)STREAM_DATA (bgp_nexthop_buf);
SET_FLAG (api.message, ZAPI_MESSAGE_IFINDEX);
- api.ifindex_num = 1;
- api.ifindex = &ifindex;
+ api.ifindex_num = valid_nh_count;
+ api.ifindex = (ifindex_t *)STREAM_DATA (bgp_ifindices_buf);
SET_FLAG (api.message, ZAPI_MESSAGE_METRIC);
api.metric = info->attr->med;
@@ -1071,6 +1159,7 @@
zclient->ipv6_route_delete = zebra_read_ipv6;
bgp_nexthop_buf = stream_new(BGP_NEXTHOP_BUF_SIZE);
+ bgp_ifindices_buf = stream_new(BGP_IFINDICES_BUF_SIZE);
}
void