bgpd/bgp_damp.h

   1 // SPDX-License-Identifier: GPL-2.0-or-later
   2 /* BGP flap dampening
   3  * Copyright (C) 2001 IP Infusion Inc.
   4  */
   5
   6 #ifndef _QUAGGA_BGP_DAMP_H
   7 #define _QUAGGA_BGP_DAMP_H
   8
   9 #include "bgpd/bgp_table.h"
  10
  11 /* Structure maintained on a per-route basis. */
  12 struct bgp_damp_info {
  13         /* Doubly linked list.  This information must be linked to
  14            reuse_list or no_reuse_list.  */
  15         struct bgp_damp_info *next;
  16         struct bgp_damp_info *prev;
  17
  18         /* Figure-of-merit.  */
  19         unsigned int penalty;
  20
  21         /* Number of flapping.  */
  22         unsigned int flap;
  23
  24         /* First flap time  */
  25         time_t start_time;
  26
  27         /* Last time penalty was updated.  */
  28         time_t t_updated;
  29
  30         /* Time of route start to be suppressed.  */
  31         time_t suppress_time;
  32
  33         /* Back reference to bgp_path_info. */
  34         struct bgp_path_info *path;
  35
  36         /* Back reference to bgp_node. */
  37         struct bgp_dest *dest;
  38
  39         /* Current index in the reuse_list. */
  40         int index;
  41
  42         /* Last time message type. */
  43         uint8_t lastrecord;
  44 #define BGP_RECORD_UPDATE       1U
  45 #define BGP_RECORD_WITHDRAW     2U
  46
  47         afi_t afi;
  48         safi_t safi;
  49 };
  50
  51 /* Specified parameter set configuration. */
  52 struct bgp_damp_config {
  53         /* Value over which routes suppressed.  */
  54         unsigned int suppress_value;
  55
  56         /* Value below which suppressed routes reused.  */
  57         unsigned int reuse_limit;
  58
  59         /* Max time a route can be suppressed.  */
  60         time_t max_suppress_time;
  61
  62         /* Time during which accumulated penalty reduces by half.  */
  63         time_t half_life;
  64
  65         /* Non-configurable parameters but fixed at implementation time.
  66          * To change this values, init_bgp_damp() should be modified.
  67          */
  68         time_t tmax; /* Max time previous instability retained */
  69         unsigned int reuse_list_size;  /* Number of reuse lists */
  70         unsigned int reuse_index_size; /* Size of reuse index array */
  71
  72         /* Non-configurable parameters.  Most of these are calculated from
  73          * the configurable parameters above.
  74          */
  75         unsigned int ceiling;             /* Max value a penalty can attain */
  76         unsigned int decay_rate_per_tick; /* Calculated from half-life */
  77         unsigned int decay_array_size; /* Calculated using config parameters */
  78         double scale_factor;
  79         unsigned int reuse_scale_factor;
  80
  81         /* Decay array per-set based. */
  82         double *decay_array;
  83
  84         /* Reuse index array per-set based. */
  85         int *reuse_index;
  86
  87         /* Reuse list array per-set based. */
  88         struct bgp_damp_info **reuse_list;
  89         int reuse_offset;
  90
  91         /* All dampening information which is not on reuse list.  */
  92         struct bgp_damp_info *no_reuse_list;
  93
  94         /* Reuse timer thread per-set base. */
  95         struct event *t_reuse;
  96
  97         afi_t afi;
  98         safi_t safi;
  99 };
 100
 101 #define BGP_DAMP_NONE           0
 102 #define BGP_DAMP_USED           1
 103 #define BGP_DAMP_SUPPRESSED     2
 104
 105 /* Time granularity for reuse lists */
 106 #define DELTA_REUSE               10
 107
 108 /* Time granularity for decay arrays */
 109 #define DELTA_T                    5
 110
 111 #define DEFAULT_PENALTY         1000
 112
 113 #define DEFAULT_HALF_LIFE         15
 114 #define DEFAULT_REUSE            750
 115 #define DEFAULT_SUPPRESS        2000
 116
 117 #define REUSE_LIST_SIZE          256
 118 #define REUSE_ARRAY_SIZE        1024
 119
 120 extern int bgp_damp_enable(struct bgp *bgp, afi_t afi, safi_t safi, time_t half,
 121                            unsigned int reuse, unsigned int suppress,
 122                            time_t max);
 123 extern int bgp_damp_disable(struct bgp *bgp, afi_t afi, safi_t safi);
 124 extern int bgp_damp_withdraw(struct bgp_path_info *path, struct bgp_dest *dest,
 125                              afi_t afi, safi_t safi, int attr_change);
 126 extern int bgp_damp_update(struct bgp_path_info *path, struct bgp_dest *dest,
 127                            afi_t afi, safi_t saff);
 128 extern void bgp_damp_info_free(struct bgp_damp_info *path, int withdraw,
 129                                afi_t afi, safi_t safi);
 130 extern void bgp_damp_info_clean(afi_t afi, safi_t safi);
 131 extern int bgp_damp_decay(time_t tdiff, int penalty,
 132                           struct bgp_damp_config *damp);
 133 extern void bgp_config_write_damp(struct vty *vty, afi_t afi, safi_t safi);
 134 extern void bgp_damp_info_vty(struct vty *vty, struct bgp_path_info *path,
 135                               afi_t afi, safi_t safi, json_object *json_path);
 136 extern const char *bgp_damp_reuse_time_vty(struct vty *vty,
 137                                            struct bgp_path_info *path,
 138                                            char *timebuf, size_t len, afi_t afi,
 139                                            safi_t safi, bool use_json,
 140                                            json_object *json);
 141 extern int bgp_show_dampening_parameters(struct vty *vty, afi_t afi,
 142                                          safi_t safi, uint16_t show_flags);
 143
 144 #endif /* _QUAGGA_BGP_DAMP_H */