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 along
  17  * with this program; see the file COPYING; if not, write to the Free Software
  18  * Foundation, Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA
  19  */
  20
  21 #ifndef _QUAGGA_BGP_DAMP_H
  22 #define _QUAGGA_BGP_DAMP_H
  23
  24 #include "bgpd/bgp_table.h"
  25
  26 /* Structure maintained on a per-route basis. */
  27 struct bgp_damp_info {
  28         /* Doubly linked list.  This information must be linked to
  29            reuse_list or no_reuse_list.  */
  30         struct bgp_damp_info *next;
  31         struct bgp_damp_info *prev;
  32
  33         /* Figure-of-merit.  */
  34         unsigned int penalty;
  35
  36         /* Number of flapping.  */
  37         unsigned int flap;
  38
  39         /* First flap time  */
  40         time_t start_time;
  41
  42         /* Last time penalty was updated.  */
  43         time_t t_updated;
  44
  45         /* Time of route start to be suppressed.  */
  46         time_t suppress_time;
  47
  48         /* Back reference to bgp_path_info. */
  49         struct bgp_path_info *path;
  50
  51         /* Back reference to bgp_node. */
  52         struct bgp_dest *dest;
  53
  54         /* Current index in the reuse_list. */
  55         int index;
  56
  57         /* Last time message type. */
  58         uint8_t lastrecord;
  59 #define BGP_RECORD_UPDATE       1U
  60 #define BGP_RECORD_WITHDRAW     2U
  61
  62         afi_t afi;
  63         safi_t safi;
  64 };
  65
  66 /* Specified parameter set configuration. */
  67 struct bgp_damp_config {
  68         /* Value over which routes suppressed.  */
  69         unsigned int suppress_value;
  70
  71         /* Value below which suppressed routes reused.  */
  72         unsigned int reuse_limit;
  73
  74         /* Max time a route can be suppressed.  */
  75         time_t max_suppress_time;
  76
  77         /* Time during which accumulated penalty reduces by half.  */
  78         time_t half_life;
  79
  80         /* Non-configurable parameters but fixed at implementation time.
  81          * To change this values, init_bgp_damp() should be modified.
  82          */
  83         time_t tmax; /* Max time previous instability retained */
  84         unsigned int reuse_list_size;  /* Number of reuse lists */
  85         unsigned int reuse_index_size; /* Size of reuse index array */
  86
  87         /* Non-configurable parameters.  Most of these are calculated from
  88          * the configurable parameters above.
  89          */
  90         unsigned int ceiling;             /* Max value a penalty can attain */
  91         unsigned int decay_rate_per_tick; /* Calculated from half-life */
  92         unsigned int decay_array_size; /* Calculated using config parameters */
  93         double scale_factor;
  94         unsigned int reuse_scale_factor;
  95
  96         /* Decay array per-set based. */
  97         double *decay_array;
  98
  99         /* Reuse index array per-set based. */
 100         int *reuse_index;
 101
 102         /* Reuse list array per-set based. */
 103         struct bgp_damp_info **reuse_list;
 104         int reuse_offset;
 105
 106         /* All dampening information which is not on reuse list.  */
 107         struct bgp_damp_info *no_reuse_list;
 108
 109         /* Reuse timer thread per-set base. */
 110         struct thread *t_reuse;
 111
 112         afi_t afi;
 113         safi_t safi;
 114 };
 115
 116 #define BGP_DAMP_NONE           0
 117 #define BGP_DAMP_USED           1
 118 #define BGP_DAMP_SUPPRESSED     2
 119
 120 /* Time granularity for reuse lists */
 121 #define DELTA_REUSE               10
 122
 123 /* Time granularity for decay arrays */
 124 #define DELTA_T                    5
 125
 126 #define DEFAULT_PENALTY         1000
 127
 128 #define DEFAULT_HALF_LIFE         15
 129 #define DEFAULT_REUSE            750
 130 #define DEFAULT_SUPPRESS        2000
 131
 132 #define REUSE_LIST_SIZE          256
 133 #define REUSE_ARRAY_SIZE        1024
 134
 135 extern int bgp_damp_enable(struct bgp *, afi_t, safi_t, time_t, unsigned int,
 136                            unsigned int, time_t);
 137 extern int bgp_damp_disable(struct bgp *, afi_t, safi_t);
 138 extern int bgp_damp_withdraw(struct bgp_path_info *path, struct bgp_dest *dest,
 139                              afi_t afi, safi_t safi, int attr_change);
 140 extern int bgp_damp_update(struct bgp_path_info *path, struct bgp_dest *dest,
 141                            afi_t afi, safi_t saff);
 142 extern void bgp_damp_info_free(struct bgp_damp_info *path, int withdraw,
 143                                afi_t afi, safi_t safi);
 144 extern void bgp_damp_info_clean(afi_t afi, safi_t safi);
 145 extern int bgp_damp_decay(time_t, int, struct bgp_damp_config *damp);
 146 extern void bgp_config_write_damp(struct vty *, afi_t afi, safi_t safi);
 147 extern void bgp_damp_info_vty(struct vty *vty, struct bgp_path_info *path,
 148                               afi_t afi, safi_t safi, json_object *json_path);
 149 extern const char *bgp_damp_reuse_time_vty(struct vty *vty,
 150                                            struct bgp_path_info *path,
 151                                            char *timebuf, size_t len, afi_t afi,
 152                                            safi_t safi, bool use_json,
 153                                            json_object *json);
 154 extern int bgp_show_dampening_parameters(struct vty *vty, afi_t, safi_t,
 155                                          uint16_t);
 156
 157 #endif /* _QUAGGA_BGP_DAMP_H */