bgpd: added bgp_nexthop_afi()

Signed-off-by: Daniel Walton <dwalton@cumulusnetworks.com>
Added bgp_nexthop_afi() to have one place that determines what the
Nexthop AFI is for bgp_packet_mpattr_start()

diff --git a/bgpd/bgp_attr.c b/bgpd/bgp_attr.c
index d80b9f237b1a1d51ab0b7e5c64c4d6d22ba61bb7..5c444869b4d2e8c0e22c44b3e0db938262b05bc8 100644 (file)
--- a/bgpd/bgp_attr.c
+++ b/bgpd/bgp_attr.c
@@ -2827,10 +2827,6 @@ bgp_packet_mpattr_start (struct stream *s, afi_t afi, safi_t safi, afi_t nh_afi,
 
   stream_putw (s, pkt_afi);    /* AFI */
   stream_putc (s, pkt_safi);   /* SAFI */
-  if (afi == AFI_L2VPN)
-    nh_afi = AFI_L2VPN;
-  else if (nh_afi == AFI_MAX)
-    nh_afi = BGP_NEXTHOP_AFI_FROM_NHLEN(attr->extra->mp_nexthop_len);
 
   /* Nexthop */
   switch (nh_afi)
@@ -3099,6 +3095,27 @@ bgp_packet_mpattr_end (struct stream *s, size_t sizep)
   stream_putw_at (s, sizep, (stream_get_endp (s) - sizep) - 2);
 }
 
+
+/* Return the Nexthop AFI that should be used */
+afi_t
+bgp_nexthop_afi (struct peer *peer, afi_t afi, safi_t safi, struct attr *attr)
+{
+  afi_t nh_afi;
+
+  if (peer_cap_enhe(peer, afi, safi)) {
+    nh_afi = AFI_IP6;
+  } else {
+    if (afi == AFI_L2VPN)
+      nh_afi = AFI_L2VPN;
+    else if (safi == SAFI_LABELED_UNICAST)
+      nh_afi = afi;
+    else
+      nh_afi = BGP_NEXTHOP_AFI_FROM_NHLEN(attr->extra->mp_nexthop_len);
+  }
+
+  return nh_afi;
+}
+
 /* Make attribute packet. */
 bgp_size_t
 bgp_packet_attribute (struct bgp *bgp, struct peer *peer,
@@ -3115,6 +3132,7 @@ bgp_packet_attribute (struct bgp *bgp, struct peer *peer,
   int send_as4_path = 0;
   int send_as4_aggregator = 0;
   int use32bit = (CHECK_FLAG (peer->cap, PEER_CAP_AS4_RCV)) ? 1 : 0;
+  afi_t nh_afi;
 
   if (! bgp)
     bgp = peer->bgp;
@@ -3127,10 +3145,8 @@ bgp_packet_attribute (struct bgp *bgp, struct peer *peer,
     {
       size_t mpattrlen_pos = 0;
 
-      mpattrlen_pos = bgp_packet_mpattr_start(s, afi, safi,
-                                              (peer_cap_enhe(peer, afi, safi) ? AFI_IP6 :
-                                               AFI_MAX), /* get from NH */
-                                              vecarr, attr);
+      nh_afi = bgp_nexthop_afi(peer, afi, safi, attr);
+      mpattrlen_pos = bgp_packet_mpattr_start(s, afi, safi, nh_afi, vecarr, attr);
       bgp_packet_mpattr_prefix(s, afi, safi, p, prd, tag,
                                addpath_encode, addpath_tx_id, attr);
       bgp_packet_mpattr_end(s, mpattrlen_pos);

diff --git a/bgpd/bgp_attr.h b/bgpd/bgp_attr.h
index 1df1faf93937cea2950ca8686979a06b1b0e9b9b..2931b2f2b65509e2174e9b55a5a5ca26a4644d0f 100644 (file)
--- a/bgpd/bgp_attr.h
+++ b/bgpd/bgp_attr.h
@@ -249,6 +249,8 @@ extern struct attr *bgp_attr_default_set (struct attr *attr, u_char);
 extern struct attr *bgp_attr_aggregate_intern (struct bgp *, u_char,
                                         struct aspath *, 
                                         struct community *, int as_set, u_char);
+extern afi_t bgp_nexthop_afi (struct peer *peer, afi_t afi, safi_t safi,
+                              struct attr *attr);
 extern bgp_size_t bgp_packet_attribute (struct bgp *bgp, struct peer *,
                                        struct stream *, struct attr *,
                                        struct bpacket_attr_vec_arr *vecarr,

diff --git a/bgpd/bgp_updgrp_packet.c b/bgpd/bgp_updgrp_packet.c
index f734763b70034e2841b67b8a09fbafd18c6d41cc..8a4824f85967f0bc1adba535fa9fbf45088d3acd 100644 (file)
--- a/bgpd/bgp_updgrp_packet.c
+++ b/bgpd/bgp_updgrp_packet.c
@@ -656,6 +656,7 @@ subgroup_update_packet (struct update_subgroup *subgrp)
   u_int32_t addpath_tx_id = 0;
   struct prefix_rd *prd = NULL;
   char label_buf[20];
+  afi_t nh_afi;
 
   if (!subgrp)
     return NULL;
@@ -767,11 +768,11 @@ subgroup_update_packet (struct update_subgroup *subgrp)
           if (bgp_labeled_safi(safi))
             sprintf (label_buf, "label %u", label_pton(tag));
 
-         if (stream_empty (snlri))
-           mpattrlen_pos = bgp_packet_mpattr_start (snlri, afi, safi,
-                                                     (peer_cap_enhe(peer, afi, safi) ? AFI_IP6 :
-                                                      AFI_MAX), /* get from NH */
+         if (stream_empty (snlri)) {
+            nh_afi = bgp_nexthop_afi(peer, afi, safi, adv->baa->attr);
+            mpattrlen_pos = bgp_packet_mpattr_start (snlri, afi, safi, nh_afi,
                                                      &vecarr, adv->baa->attr);
+          }
 
           bgp_packet_mpattr_prefix (snlri, afi, safi, &rn->p, prd,
                                     tag, addpath_encode, addpath_tx_id, adv->baa->attr);