bgpd/bgp_mpath.h

   1 /* $QuaggaId: Format:%an, %ai, %h$ $
   2  *
   3  * BGP Multipath
   4  * Copyright (C) 2010 Google Inc.
   5  *
   6  * This file is part of Quagga
   7  *
   8  * Quagga is free software; you can redistribute it and/or modify it
   9  * under the terms of the GNU General Public License as published by the
  10  * Free Software Foundation; either version 2, or (at your option) any
  11  * later version.
  12  *
  13  * Quagga is distributed in the hope that it will be useful, but
  14  * WITHOUT ANY WARRANTY; without even the implied warranty of
  15  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
  16  * General Public License for more details.
  17  *
  18  * You should have received a copy of the GNU General Public License
  19  * along with Quagga; see the file COPYING.  If not, write to the Free
  20  * Software Foundation, Inc., 59 Temple Place - Suite 330, Boston, MA
  21  * 02111-1307, USA.
  22  */
  23
  24 #ifndef _QUAGGA_BGP_MPATH_H
  25 #define _QUAGGA_BGP_MPATH_H
  26
  27 /* Supplemental information linked to bgp_info for keeping track of
  28  * multipath selections, lazily allocated to save memory
  29  */
  30 struct bgp_info_mpath
  31 {
  32   /* Points to the first multipath (on bestpath) or the next multipath */
  33   struct bgp_info_mpath *mp_next;
  34
  35   /* Points to the previous multipath or NULL on bestpath */
  36   struct bgp_info_mpath *mp_prev;
  37
  38   /* Points to bgp_info associated with this multipath info */
  39   struct bgp_info *mp_info;
  40
  41   /* When attached to best path, the number of selected multipaths */
  42   u_int32_t mp_count;
  43
  44   /* Aggregated attribute for advertising multipath route */
  45   struct attr *mp_attr;
  46 };
  47
  48 /* Functions to support maximum-paths configuration */
  49 extern int bgp_maximum_paths_set (struct bgp *, afi_t, safi_t, int, u_int16_t,
  50                                   u_int16_t);
  51 extern int bgp_maximum_paths_unset (struct bgp *, afi_t, safi_t, int);
  52
  53 /* Functions used by bgp_best_selection to record current
  54  * multipath selections
  55  */
  56 extern int bgp_info_nexthop_cmp (struct bgp_info *bi1, struct bgp_info *bi2);
  57 extern void bgp_mp_list_init (struct list *);
  58 extern void bgp_mp_list_clear (struct list *);
  59 extern void bgp_mp_list_add (struct list *, struct bgp_info *);
  60 extern void bgp_mp_dmed_deselect (struct bgp_info *);
  61 extern void bgp_info_mpath_update (struct bgp_node *, struct bgp_info *,
  62                                    struct bgp_info *, struct list *,
  63                                    struct bgp_maxpaths_cfg *);
  64 extern void bgp_info_mpath_aggregate_update (struct bgp_info *,
  65                                              struct bgp_info *);
  66
  67 /* Unlink and free multipath information associated with a bgp_info */
  68 extern void bgp_info_mpath_dequeue (struct bgp_info *);
  69 extern void bgp_info_mpath_free (struct bgp_info_mpath **);
  70
  71 /* Walk list of multipaths associated with a best path */
  72 extern struct bgp_info *bgp_info_mpath_first (struct bgp_info *);
  73 extern struct bgp_info *bgp_info_mpath_next (struct bgp_info *);
  74
  75 /* Accessors for multipath information */
  76 extern u_int32_t bgp_info_mpath_count (struct bgp_info *);
  77 extern struct attr *bgp_info_mpath_attr (struct bgp_info *);
  78
  79 #endif /* _QUAGGA_BGP_MPATH_H */