BGP: Allow receiving multicast routes

1 files changed, 45 insertions, 27 deletions

diff --git a/proto/bgp/packets.c b/proto/bgp/packets.c
index 1a1e7b7..8e657cc 100644
--- a/proto/bgp/packets.c
+++ b/proto/bgp/packets.c
@@ -6,7 +6,7 @@
  *	Can be freely distributed and used under the terms of the GNU GPL.
  */
 
-#undef LOCAL_DEBUG
+#define LOCAL_DEBUG
 
 #include "nest/bird.h"
 #include "nest/iface.h"
@@ -228,7 +228,7 @@ bgp_create_open(struct bgp_conn *conn, byte *buf)
 }
 
 static unsigned int
-bgp_encode_prefixes(struct bgp_proto *p, byte *w, struct bgp_bucket *buck, unsigned int remains)
+bgp_encode_prefixes(struct bgp_bucket_info *bi, byte *w, struct bgp_bucket *buck, unsigned int remains)
 {
   byte *start = w;
   ip_addr a;
@@ -246,20 +246,20 @@ bgp_encode_prefixes(struct bgp_proto *p, byte *w, struct bgp_bucket *buck, unsig
       w += bytes;
       remains -= bytes + 1;
       rem_node(&px->bucket_node);
-      fib_delete(&p->prefix_fib, px);
+      fib_delete(&bi->prefix_fib, px);
     }
   return w - start;
 }
 
 static void
-bgp_flush_prefixes(struct bgp_proto *p, struct bgp_bucket *buck)
+bgp_flush_prefixes(struct bgp_proto *p, struct bgp_bucket_info *bi, struct bgp_bucket *buck)
 {
   while (!EMPTY_LIST(buck->prefixes))
     {
       struct bgp_prefix *px = SKIP_BACK(struct bgp_prefix, bucket_node, HEAD(buck->prefixes));
       log(L_ERR "%s: - route %I/%d skipped", p->p.name, px->n.prefix, px->n.pxlen);
       rem_node(&px->bucket_node);
-      fib_delete(&p->prefix_fib, px);
+      fib_delete(&bi->prefix_fib, px);
     }
 }
 
@@ -269,6 +269,7 @@ static byte *
 bgp_create_update(struct bgp_conn *conn, byte *buf)
 {
   struct bgp_proto *p = conn->bgp;
+  struct bgp_bucket_info *bi = &p->unicast_buckets;
   struct bgp_bucket *buck;
   int remains = BGP_MAX_PACKET_LENGTH - BGP_HEADER_LENGTH - 4;
   byte *w;
@@ -277,10 +278,10 @@ bgp_create_update(struct bgp_conn *conn, byte *buf)
   int a_size = 0;
 
   w = buf+2;
-  if ((buck = p->withdraw_bucket) && !EMPTY_LIST(buck->prefixes))
+  if ((buck = bi->withdraw_bucket) && !EMPTY_LIST(buck->prefixes))
     {
       DBG("Withdrawn routes:\n");
-      wd_size = bgp_encode_prefixes(p, w, buck, remains);
+      wd_size = bgp_encode_prefixes(bi, w, buck, remains);
       w += wd_size;
       remains -= wd_size;
     }
@@ -288,13 +289,13 @@ bgp_create_update(struct bgp_conn *conn, byte *buf)
 
   if (remains >= 3072)
     {
-      while ((buck = (struct bgp_bucket *) HEAD(p->bucket_queue))->send_node.next)
+      while ((buck = (struct bgp_bucket *) HEAD(bi->bucket_queue))->send_node.next)
 	{
 	  if (EMPTY_LIST(buck->prefixes))
 	    {
 	      DBG("Deleting empty bucket %p\n", buck);
 	      rem_node(&buck->send_node);
-	      bgp_free_bucket(p, buck);
+	      bgp_free_bucket(bi, buck);
 	      continue;
 	    }
 
@@ -304,15 +305,15 @@ bgp_create_update(struct bgp_conn *conn, byte *buf)
 	  if (a_size < 0)
 	    {
 	      log(L_ERR "%s: Attribute list too long, skipping corresponding routes", p->p.name);
-	      bgp_flush_prefixes(p, buck);
+	      bgp_flush_prefixes(p, bi, buck);
 	      rem_node(&buck->send_node);
-	      bgp_free_bucket(p, buck);
+	      bgp_free_bucket(bi, buck);
 	      continue;
 	    }
 
 	  put_u16(w, a_size);
 	  w += a_size + 2;
-	  r_size = bgp_encode_prefixes(p, w, buck, remains - a_size);
+	  r_size = bgp_encode_prefixes(bi, w, buck, remains - a_size);
 	  w += r_size;
 	  break;
 	}
@@ -337,6 +338,7 @@ static byte *
 bgp_create_update(struct bgp_conn *conn, byte *buf)
 {
   struct bgp_proto *p = conn->bgp;
+  struct bgp_bucket_info *bi = &p->unicast_buckets;
   struct bgp_bucket *buck;
   int size, second, rem_stored;
   int remains = BGP_MAX_PACKET_LENGTH - BGP_HEADER_LENGTH - 4;
@@ -349,14 +351,14 @@ bgp_create_update(struct bgp_conn *conn, byte *buf)
   put_u16(buf, 0);
   w = buf+4;
 
-  if ((buck = p->withdraw_bucket) && !EMPTY_LIST(buck->prefixes))
+  if ((buck = bi->withdraw_bucket) && !EMPTY_LIST(buck->prefixes))
     {
       DBG("Withdrawn routes:\n");
       tmp = bgp_attach_attr_wa(&ea, bgp_linpool, BA_MP_UNREACH_NLRI, remains-8);
       *tmp++ = 0;
       *tmp++ = BGP_AF_IPV6;
-      *tmp++ = 1;
-      ea->attrs[0].u.ptr->length = 3 + bgp_encode_prefixes(p, tmp, buck, remains-11);
+      *tmp++ = BGP_SAF_UNICAST;
+      ea->attrs[0].u.ptr->length = 3 + bgp_encode_prefixes(bi, tmp, buck, remains-11);
       size = bgp_encode_attrs(p, w, ea, remains);
       ASSERT(size >= 0);
       w += size;
@@ -365,13 +367,13 @@ bgp_create_update(struct bgp_conn *conn, byte *buf)
 
   if (remains >= 3072)
     {
-      while ((buck = (struct bgp_bucket *) HEAD(p->bucket_queue))->send_node.next)
+      while ((buck = (struct bgp_bucket *) HEAD(bi->bucket_queue))->send_node.next)
 	{
 	  if (EMPTY_LIST(buck->prefixes))
 	    {
 	      DBG("Deleting empty bucket %p\n", buck);
 	      rem_node(&buck->send_node);
-	      bgp_free_bucket(p, buck);
+	      bgp_free_bucket(bi, buck);
 	      continue;
 	    }
 
@@ -383,9 +385,9 @@ bgp_create_update(struct bgp_conn *conn, byte *buf)
 	  if (size < 0)
 	    {
 	      log(L_ERR "%s: Attribute list too long, skipping corresponding routes", p->p.name);
-	      bgp_flush_prefixes(p, buck);
+	      bgp_flush_prefixes(p, bi, buck);
 	      rem_node(&buck->send_node);
-	      bgp_free_bucket(p, buck);
+	      bgp_free_bucket(bi, buck);
 	      continue;
 	    }
 	  w += size;
@@ -433,9 +435,9 @@ bgp_create_update(struct bgp_conn *conn, byte *buf)
 			  log(L_ERR "%s: Missing link-local next hop address, skipping corresponding routes", p->p.name);
 			  w = w_stored;
 			  remains = rem_stored;
-			  bgp_flush_prefixes(p, buck);
+			  bgp_flush_prefixes(p, bi, buck);
 			  rem_node(&buck->send_node);
-			  bgp_free_bucket(p, buck);
+			  bgp_free_bucket(bi, buck);
 			  continue;
 			case MLL_IGNORE:
 			  break;
@@ -467,7 +469,7 @@ bgp_create_update(struct bgp_conn *conn, byte *buf)
 	    }
 
 	  *tmp++ = 0;			/* No SNPA information */
-	  tmp += bgp_encode_prefixes(p, tmp, buck, remains - (8+3+32+1));
+	  tmp += bgp_encode_prefixes(bi, tmp, buck, remains - (8+3+32+1));
 	  ea->attrs[0].u.ptr->length = tmp - tstart;
 	  size = bgp_encode_attrs(p, w, ea, remains);
 	  ASSERT(size >= 0);
@@ -804,6 +806,7 @@ bgp_rx_open(struct bgp_conn *conn, byte *pkt, int len)
   conn->keepalive_time = p->cf->keepalive_time ? : conn->hold_time / 3;
   p->remote_id = id;
   p->as4_session = conn->want_as4_support && conn->peer_as4_support;
+  p->multicast_session = conn->want_multicast_support && conn->peer_multicast_support;
 
   DBG("BGP: Hold timer set to %d, keepalive to %d, AS to %d, ID to %x, AS4 session to %d\n", conn->hold_time, conn->keepalive_time, p->remote_as, p->remote_id, p->as4_session);
 
@@ -930,7 +933,7 @@ bgp_do_rx_update(struct bgp_conn *conn,
     }							\
   else							\
     af = 0;						\
-  if (af == BGP_AF_IPV6)
+  if (af == BGP_AF)
 
 static void
 bgp_do_rx_update(struct bgp_conn *conn,
@@ -947,6 +950,7 @@ bgp_do_rx_update(struct bgp_conn *conn,
   ip_addr prefix;
   net *n;
   int err = 0, pxlen;
+  int multicast;
 
   p->mp_reach_len = 0;
   p->mp_unreach_len = 0;
@@ -956,17 +960,30 @@ bgp_do_rx_update(struct bgp_conn *conn,
 
   DO_NLRI(mp_unreach)
     {
+      multicast = (sub == BGP_SAF_MULTICAST);
+
+      if (multicast)
+	ASSERT(p->multicast_session);
+
       while (len)
 	{
 	  DECODE_PREFIX(x, len);
-	  DBG("Withdraw %I/%d\n", prefix, pxlen);
-	  if (n = net_find(p->p.table, prefix, pxlen))
+	  DBG("Withdraw %I/%d%s\n", prefix, pxlen, multicast ? " MC" : "");
+	  if (n = net_find_cast(p->p.table, prefix, pxlen, multicast ? RTC_MULTICAST : RTC_UNICAST))
 	    rte_update(p->p.table, n, &p->p, &p->p, NULL);
 	}
     }
 
   DO_NLRI(mp_reach)
     {
+      multicast = (sub == BGP_SAF_MULTICAST);
+
+      if (multicast)
+	{
+	  ASSERT(p->multicast_session);
+	  a0->cast = RTC_MULTICAST;
+	}
+
       /* Create fake NEXT_HOP attribute */
       if (len < 1 || (*x != 16 && *x != 32) || len < *x + 2)
 	goto bad;
@@ -991,13 +1008,14 @@ bgp_do_rx_update(struct bgp_conn *conn,
       if (bgp_set_next_hop(p, a0))
 	{
 	  a = rta_lookup(a0);
+
 	  while (len)
 	    {
 	      rte *e;
 	      DECODE_PREFIX(x, len);
-	      DBG("Add %I/%d\n", prefix, pxlen);
+	      DBG("Add %I/%d%s\n", prefix, pxlen, multicast ? " MC" : "");
 	      e = rte_get_temp(rta_clone(a));
-	      n = net_get(p->p.table, prefix, pxlen);
+	      n = net_get_cast(p->p.table, prefix, pxlen, multicast ? RTC_MULTICAST : RTC_UNICAST);
 	      e->net = n;
 	      e->pflags = 0;
 	      rte_update(p->p.table, n, &p->p, &p->p, e);