lib/nexthop_group.h

   1 /*
   2  * Nexthop Group structure definition.
   3  * Copyright (C) 2018 Cumulus Networks, Inc.
   4  *                    Donald Sharp
   5  *
   6  * This program 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 Free
   8  * Software Foundation; either version 2 of the License, or (at your option)
   9  * any later version.
  10  *
  11  * This program is distributed in the hope that it will be useful, but WITHOUT
  12  * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
  13  * FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License for
  14  * 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 __NEXTHOP_GROUP__
  22 #define __NEXTHOP_GROUP__
  23
  24 #include <vty.h>
  25 #include "json.h"
  26
  27 #ifdef __cplusplus
  28 extern "C" {
  29 #endif
  30
  31 /*
  32  * What is a nexthop group?
  33  *
  34  * A nexthop group is a collection of nexthops that make up
  35  * the ECMP path for the route.
  36  *
  37  * This module provides a proper abstraction to this idea.
  38  */
  39 struct nexthop_group {
  40         struct nexthop *nexthop;
  41 };
  42
  43 struct nexthop_group *nexthop_group_new(void);
  44 void nexthop_group_delete(struct nexthop_group **nhg);
  45
  46 void nexthop_group_copy(struct nexthop_group *to,
  47                         const struct nexthop_group *from);
  48
  49 /*
  50  * Copy a list of nexthops in 'nh' to an nhg, enforcing canonical sort order
  51  */
  52 void nexthop_group_copy_nh_sorted(struct nexthop_group *nhg,
  53                                   const struct nexthop *nh);
  54
  55 void copy_nexthops(struct nexthop **tnh, const struct nexthop *nh,
  56                    struct nexthop *rparent);
  57
  58 uint32_t nexthop_group_hash_no_recurse(const struct nexthop_group *nhg);
  59 uint32_t nexthop_group_hash(const struct nexthop_group *nhg);
  60 void nexthop_group_mark_duplicates(struct nexthop_group *nhg);
  61
  62 /* Add a nexthop to a list, enforcing the canonical sort order. */
  63 void nexthop_group_add_sorted(struct nexthop_group *nhg,
  64                               struct nexthop *nexthop);
  65
  66 /* The following for loop allows to iterate over the nexthop
  67  * structure of routes.
  68  *
  69  * head:      The pointer to the first nexthop in the chain.
  70  *
  71  * nexthop:   The pointer to the current nexthop, either in the
  72  *            top-level chain or in a resolved chain.
  73  */
  74 #define ALL_NEXTHOPS(head, nhop)                                        \
  75         (nhop) = (head.nexthop);                                        \
  76         (nhop);                                                         \
  77         (nhop) = nexthop_next(nhop)
  78
  79 #define ALL_NEXTHOPS_PTR(head, nhop)                                    \
  80         (nhop) = ((head)->nexthop);                                     \
  81         (nhop);                                                         \
  82         (nhop) = nexthop_next(nhop)
  83
  84
  85 #define NHGC_NAME_SIZE 80
  86
  87 struct nexthop_group_cmd {
  88
  89         RB_ENTRY(nexthop_group_cmd) nhgc_entry;
  90
  91         char name[NHGC_NAME_SIZE];
  92
  93         /* Name of group containing backup nexthops (if set) */
  94         char backup_list_name[NHGC_NAME_SIZE];
  95
  96         struct nexthop_group nhg;
  97
  98         struct list *nhg_list;
  99
 100         QOBJ_FIELDS;
 101 };
 102 RB_HEAD(nhgc_entry_head, nexthp_group_cmd);
 103 RB_PROTOTYPE(nhgc_entry_head, nexthop_group_cmd, nhgc_entry,
 104              nexthop_group_cmd_compare)
 105 DECLARE_QOBJ_TYPE(nexthop_group_cmd);
 106
 107 /*
 108  * Initialize nexthop_groups.  If you are interested in when
 109  * a nexthop_group is added/deleted/modified, then set the
 110  * appropriate callback functions to handle it in your
 111  * code
 112  */
 113 void nexthop_group_init(
 114         void (*create)(const char *name),
 115         void (*add_nexthop)(const struct nexthop_group_cmd *nhgc,
 116                             const struct nexthop *nhop),
 117         void (*del_nexthop)(const struct nexthop_group_cmd *nhgc,
 118                             const struct nexthop *nhop),
 119         void (*destroy)(const char *name));
 120
 121 void nexthop_group_enable_vrf(struct vrf *vrf);
 122 void nexthop_group_disable_vrf(struct vrf *vrf);
 123 void nexthop_group_interface_state_change(struct interface *ifp,
 124                                           ifindex_t oldifindex);
 125
 126 extern struct nexthop *nexthop_exists(const struct nexthop_group *nhg,
 127                                       const struct nexthop *nh);
 128 /* This assumes ordered */
 129 extern bool nexthop_group_equal_no_recurse(const struct nexthop_group *nhg1,
 130                                            const struct nexthop_group *nhg2);
 131
 132 /* This assumes ordered */
 133 extern bool nexthop_group_equal(const struct nexthop_group *nhg1,
 134                                 const struct nexthop_group *nhg2);
 135
 136 extern struct nexthop_group_cmd *nhgc_find(const char *name);
 137
 138 extern void nexthop_group_write_nexthop_simple(struct vty *vty,
 139                                                const struct nexthop *nh,
 140                                                char *altifname);
 141 extern void nexthop_group_write_nexthop(struct vty *vty,
 142                                         const struct nexthop *nh);
 143
 144 extern void nexthop_group_json_nexthop(json_object *j,
 145                                        const struct nexthop *nh);
 146
 147 /* Return the number of nexthops in this nhg */
 148 extern uint8_t nexthop_group_nexthop_num(const struct nexthop_group *nhg);
 149 extern uint8_t
 150 nexthop_group_nexthop_num_no_recurse(const struct nexthop_group *nhg);
 151 extern uint8_t
 152 nexthop_group_active_nexthop_num(const struct nexthop_group *nhg);
 153 extern uint8_t
 154 nexthop_group_active_nexthop_num_no_recurse(const struct nexthop_group *nhg);
 155
 156 #ifdef __cplusplus
 157 }
 158 #endif
 159
 160 #endif