bgpd: merge osr/google-bgp-multipath

this patchset allows collapsing multiple received routes in BGP into one
multipath route that will, if readvertised, contain an aggregate of all
received attributes.

1 files changed, 80 insertions, 0 deletions

diff --git a/bgpd/bgp_mpath.h b/bgpd/bgp_mpath.h
new file mode 100644
index 00000000..37b9ac8b
--- /dev/null
+++ b/bgpd/bgp_mpath.h
@@ -0,0 +1,80 @@
+/* $QuaggaId: Format:%an, %ai, %h$ $
+ *
+ * BGP Multipath
+ * Copyright (C) 2010 Google Inc.
+ *
+ * This file is part of Quagga
+ *
+ * Quagga 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.
+ *
+ * Quagga 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 Quagga; see the file COPYING.  If not, write to the Free
+ * Software Foundation, Inc., 59 Temple Place - Suite 330, Boston, MA
+ * 02111-1307, USA.
+ */
+
+#ifndef _QUAGGA_BGP_MPATH_H
+#define _QUAGGA_BGP_MPATH_H
+
+/* BGP default maximum-paths */
+#define BGP_DEFAULT_MAXPATHS 1
+
+/* Supplemental information linked to bgp_info for keeping track of
+ * multipath selections, lazily allocated to save memory
+ */
+struct bgp_info_mpath
+{
+  /* Points to the first multipath (on bestpath) or the next multipath */
+  struct bgp_info_mpath *mp_next;
+
+  /* Points to the previous multipath or NULL on bestpath */
+  struct bgp_info_mpath *mp_prev;
+
+  /* Points to bgp_info associated with this multipath info */
+  struct bgp_info *mp_info;
+
+  /* When attached to best path, the number of selected multipaths */
+  u_int32_t mp_count;
+
+  /* Aggregated attribute for advertising multipath route */
+  struct attr *mp_attr;
+};
+
+/* Functions to support maximum-paths configuration */
+extern int bgp_maximum_paths_set (struct bgp *, afi_t, safi_t, int, u_int16_t);
+extern int bgp_maximum_paths_unset (struct bgp *, afi_t, safi_t, int);
+
+/* Functions used by bgp_best_selection to record current
+ * multipath selections
+ */
+extern void bgp_mp_list_init (struct list *);
+extern void bgp_mp_list_clear (struct list *);
+extern void bgp_mp_list_add (struct list *, struct bgp_info *);
+extern void bgp_mp_dmed_deselect (struct bgp_info *);
+extern void bgp_info_mpath_update (struct bgp_node *, struct bgp_info *,
+                                   struct bgp_info *, struct list *,
+                                   struct bgp_maxpaths_cfg *);
+extern void bgp_info_mpath_aggregate_update (struct bgp_info *,
+                                             struct bgp_info *);
+
+/* Unlink and free multipath information associated with a bgp_info */
+extern void bgp_info_mpath_dequeue (struct bgp_info *);
+extern void bgp_info_mpath_free (struct bgp_info_mpath **);
+
+/* Walk list of multipaths associated with a best path */
+extern struct bgp_info *bgp_info_mpath_first (struct bgp_info *);
+extern struct bgp_info *bgp_info_mpath_next (struct bgp_info *);
+
+/* Accessors for multipath information */
+extern u_int32_t bgp_info_mpath_count (struct bgp_info *);
+extern struct attr *bgp_info_mpath_attr (struct bgp_info *);
+
+#endif /* _QUAGGA_BGP_MPATH_H */