lib/nexthop_group.h

   1 // SPDX-License-Identifier: GPL-2.0-or-later
   2 /*
   3  * Nexthop Group structure definition.
   4  * Copyright (C) 2018 Cumulus Networks, Inc.
   5  *                    Donald Sharp
   6  */
   7
   8 #ifndef __NEXTHOP_GROUP__
   9 #define __NEXTHOP_GROUP__
  10
  11 #include <vty.h>
  12 #include "json.h"
  13
  14 #ifdef __cplusplus
  15 extern "C" {
  16 #endif
  17
  18 struct nhg_resilience {
  19         uint16_t buckets;
  20         uint32_t idle_timer;
  21         uint32_t unbalanced_timer;
  22         uint64_t unbalanced_time;
  23 };
  24
  25 /*
  26  * What is a nexthop group?
  27  *
  28  * A nexthop group is a collection of nexthops that make up
  29  * the ECMP path for the route.
  30  *
  31  * This module provides a proper abstraction to this idea.
  32  */
  33 struct nexthop_group {
  34         struct nexthop *nexthop;
  35
  36         struct nhg_resilience nhgr;
  37 };
  38
  39 struct nexthop_group *nexthop_group_new(void);
  40 void nexthop_group_delete(struct nexthop_group **nhg);
  41
  42 void nexthop_group_copy(struct nexthop_group *to,
  43                         const struct nexthop_group *from);
  44
  45 /*
  46  * Copy a list of nexthops in 'nh' to an nhg, enforcing canonical sort order
  47  */
  48 void nexthop_group_copy_nh_sorted(struct nexthop_group *nhg,
  49                                   const struct nexthop *nh);
  50
  51 void copy_nexthops(struct nexthop **tnh, const struct nexthop *nh,
  52                    struct nexthop *rparent);
  53
  54 uint32_t nexthop_group_hash_no_recurse(const struct nexthop_group *nhg);
  55 uint32_t nexthop_group_hash(const struct nexthop_group *nhg);
  56 void nexthop_group_mark_duplicates(struct nexthop_group *nhg);
  57
  58 /* Add a nexthop to a list, enforcing the canonical sort order. */
  59 void nexthop_group_add_sorted(struct nexthop_group *nhg,
  60                               struct nexthop *nexthop);
  61
  62 /* The following for loop allows to iterate over the nexthop
  63  * structure of routes.
  64  *
  65  * head:      The pointer to the first nexthop in the chain.
  66  *
  67  * nexthop:   The pointer to the current nexthop, either in the
  68  *            top-level chain or in a resolved chain.
  69  */
  70 #define ALL_NEXTHOPS(head, nhop)                                        \
  71         (nhop) = (head.nexthop);                                        \
  72         (nhop);                                                         \
  73         (nhop) = nexthop_next(nhop)
  74
  75 #define ALL_NEXTHOPS_PTR(head, nhop)                                    \
  76         (nhop) = ((head)->nexthop);                                     \
  77         (nhop);                                                         \
  78         (nhop) = nexthop_next(nhop)
  79
  80
  81 #define NHGC_NAME_SIZE 80
  82
  83 struct nexthop_group_cmd {
  84
  85         RB_ENTRY(nexthop_group_cmd) nhgc_entry;
  86
  87         char name[NHGC_NAME_SIZE];
  88
  89         /* Name of group containing backup nexthops (if set) */
  90         char backup_list_name[NHGC_NAME_SIZE];
  91
  92         struct nexthop_group nhg;
  93
  94         struct list *nhg_list;
  95
  96         QOBJ_FIELDS;
  97 };
  98 RB_HEAD(nhgc_entry_head, nexthp_group_cmd);
  99 RB_PROTOTYPE(nhgc_entry_head, nexthop_group_cmd, nhgc_entry,
 100              nexthop_group_cmd_compare)
 101 DECLARE_QOBJ_TYPE(nexthop_group_cmd);
 102
 103 /*
 104  * Initialize nexthop_groups.  If you are interested in when
 105  * a nexthop_group is added/deleted/modified, then set the
 106  * appropriate callback functions to handle it in your
 107  * code
 108  *
 109  * create - The creation of the nexthop group
 110  * modify - Modification of the nexthop group when not changing a nexthop
 111  *          ( resilience as an example )
 112  * add_nexthop - A nexthop is added to the NHG
 113  * del_nexthop - A nexthop is deleted from the NHG
 114  * destroy - The NHG is deleted
 115  */
 116 void nexthop_group_init(
 117         void (*create)(const char *name),
 118         void (*modify)(const struct nexthop_group_cmd *nhgc),
 119         void (*add_nexthop)(const struct nexthop_group_cmd *nhgc,
 120                             const struct nexthop *nhop),
 121         void (*del_nexthop)(const struct nexthop_group_cmd *nhgc,
 122                             const struct nexthop *nhop),
 123         void (*destroy)(const char *name));
 124
 125 void nexthop_group_enable_vrf(struct vrf *vrf);
 126 void nexthop_group_disable_vrf(struct vrf *vrf);
 127 void nexthop_group_interface_state_change(struct interface *ifp,
 128                                           ifindex_t oldifindex);
 129
 130 extern struct nexthop *nexthop_exists(const struct nexthop_group *nhg,
 131                                       const struct nexthop *nh);
 132 /* This assumes ordered */
 133 extern bool nexthop_group_equal_no_recurse(const struct nexthop_group *nhg1,
 134                                            const struct nexthop_group *nhg2);
 135
 136 /* This assumes ordered */
 137 extern bool nexthop_group_equal(const struct nexthop_group *nhg1,
 138                                 const struct nexthop_group *nhg2);
 139
 140 extern struct nexthop_group_cmd *nhgc_find(const char *name);
 141
 142 extern void nexthop_group_write_nexthop_simple(struct vty *vty,
 143                                                const struct nexthop *nh,
 144                                                char *altifname);
 145 extern void nexthop_group_write_nexthop(struct vty *vty,
 146                                         const struct nexthop *nh);
 147
 148 extern void nexthop_group_json_nexthop(json_object *j,
 149                                        const struct nexthop *nh);
 150
 151 /* Return the number of nexthops in this nhg */
 152 extern uint8_t nexthop_group_nexthop_num(const struct nexthop_group *nhg);
 153 extern uint8_t
 154 nexthop_group_nexthop_num_no_recurse(const struct nexthop_group *nhg);
 155 extern uint8_t
 156 nexthop_group_active_nexthop_num(const struct nexthop_group *nhg);
 157 extern uint8_t
 158 nexthop_group_active_nexthop_num_no_recurse(const struct nexthop_group *nhg);
 159
 160 extern bool nexthop_group_has_label(const struct nexthop_group *nhg);
 161
 162 #ifdef __cplusplus
 163 }
 164 #endif
 165
 166 #endif