bgpd/bgp_damp.h

   1 /* BGP flap dampening
   2    Copyright (C) 2001 IP Infusion Inc.
   3
   4 This file is part of GNU Zebra.
   5
   6 GNU Zebra is free software; you can redistribute it and/or modify it
   7 under the terms of the GNU General Public License as published by the
   8 Free Software Foundation; either version 2, or (at your option) any
   9 later version.
  10
  11 GNU Zebra is distributed in the hope that it will be useful, but
  12 WITHOUT ANY WARRANTY; without even the implied warranty of
  13 MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
  14 General Public License for more details.
  15
  16 You should have received a copy of the GNU General Public License
  17 along with GNU Zebra; see the file COPYING.  If not, write to the Free
  18 Software Foundation, Inc., 59 Temple Place - Suite 330, Boston, MA
  19 02111-1307, USA.  */
  20
  21 #ifndef _QUAGGA_BGP_DAMP_H
  22 #define _QUAGGA_BGP_DAMP_H
  23
  24 #include <json/json.h>
  25
  26 /* Structure maintained on a per-route basis. */
  27 struct bgp_damp_info
  28 {
  29   /* Doubly linked list.  This information must be linked to
  30      reuse_list or no_reuse_list.  */
  31   struct bgp_damp_info *next;
  32   struct bgp_damp_info *prev;
  33
  34   /* Figure-of-merit.  */
  35   unsigned int penalty;
  36
  37   /* Number of flapping.  */
  38   unsigned int flap;
  39
  40   /* First flap time  */
  41   time_t start_time;
  42
  43   /* Last time penalty was updated.  */
  44   time_t t_updated;
  45
  46   /* Time of route start to be suppressed.  */
  47   time_t suppress_time;
  48
  49   /* Back reference to bgp_info. */
  50   struct bgp_info *binfo;
  51
  52   /* Back reference to bgp_node. */
  53   struct bgp_node *rn;
  54
  55   /* Current index in the reuse_list. */
  56   int index;
  57
  58   /* Last time message type. */
  59   u_char lastrecord;
  60 #define BGP_RECORD_UPDATE       1U
  61 #define BGP_RECORD_WITHDRAW     2U
  62
  63   afi_t afi;
  64   safi_t safi;
  65 };
  66
  67 /* Specified parameter set configuration. */
  68 struct bgp_damp_config
  69 {
  70   /* Value over which routes suppressed.  */
  71   unsigned int suppress_value;
  72
  73   /* Value below which suppressed routes reused.  */
  74   unsigned int reuse_limit;
  75
  76   /* Max time a route can be suppressed.  */
  77   time_t max_suppress_time;
  78
  79   /* Time during which accumulated penalty reduces by half.  */
  80   time_t half_life;
  81
  82   /* Non-configurable parameters but fixed at implementation time.
  83    * To change this values, init_bgp_damp() should be modified.
  84    */
  85   time_t tmax;                   /* Max time previous instability retained */
  86   unsigned int reuse_list_size;  /* Number of reuse lists */
  87   unsigned int reuse_index_size; /* Size of reuse index array */
  88
  89   /* Non-configurable parameters.  Most of these are calculated from
  90    * the configurable parameters above.
  91    */
  92   unsigned int ceiling;                 /* Max value a penalty can attain */
  93   unsigned int decay_rate_per_tick;     /* Calculated from half-life */
  94   unsigned int decay_array_size; /* Calculated using config parameters */
  95   double scale_factor;
  96   unsigned int reuse_scale_factor;
  97
  98   /* Decay array per-set based. */
  99   double *decay_array;
 100
 101   /* Reuse index array per-set based. */
 102   int *reuse_index;
 103
 104   /* Reuse list array per-set based. */
 105   struct bgp_damp_info **reuse_list;
 106   int reuse_offset;
 107
 108   /* All dampening information which is not on reuse list.  */
 109   struct bgp_damp_info *no_reuse_list;
 110
 111   /* Reuse timer thread per-set base. */
 112   struct thread* t_reuse;
 113 };
 114
 115 #define BGP_DAMP_NONE           0
 116 #define BGP_DAMP_USED           1
 117 #define BGP_DAMP_SUPPRESSED     2
 118
 119 /* Time granularity for reuse lists */
 120 #define DELTA_REUSE               10
 121
 122 /* Time granularity for decay arrays */
 123 #define DELTA_T                    5
 124
 125 #define DEFAULT_PENALTY         1000
 126
 127 #define DEFAULT_HALF_LIFE         15
 128 #define DEFAULT_REUSE            750
 129 #define DEFAULT_SUPPRESS        2000
 130
 131 #define REUSE_LIST_SIZE          256
 132 #define REUSE_ARRAY_SIZE        1024
 133
 134 extern int bgp_damp_enable (struct bgp *, afi_t, safi_t, time_t, unsigned int,
 135                      unsigned int, time_t);
 136 extern int bgp_damp_disable (struct bgp *, afi_t, safi_t);
 137 extern int bgp_damp_withdraw (struct bgp_info *, struct bgp_node *,
 138                        afi_t, safi_t, int);
 139 extern int bgp_damp_update (struct bgp_info *, struct bgp_node *, afi_t, safi_t);
 140 extern int bgp_damp_scan (struct bgp_info *, afi_t, safi_t);
 141 extern void bgp_damp_info_free (struct bgp_damp_info *, int);
 142 extern void bgp_damp_info_clean (void);
 143 extern int bgp_damp_decay (time_t, int);
 144 extern void bgp_config_write_damp (struct vty *);
 145 extern void bgp_damp_info_vty (struct vty *, struct bgp_info *, json_object *json_path);
 146 extern const char * bgp_damp_reuse_time_vty (struct vty *, struct bgp_info *,
 147                                              char *, size_t);
 148
 149 #endif /* _QUAGGA_BGP_DAMP_H */