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 struct nhg_resilience {
  32         uint16_t buckets;
  33         uint32_t idle_timer;
  34         uint32_t unbalanced_timer;
  35         uint64_t unbalanced_time;
  36 };
  37
  38 /*
  39  * What is a nexthop group?
  40  *
  41  * A nexthop group is a collection of nexthops that make up
  42  * the ECMP path for the route.
  43  *
  44  * This module provides a proper abstraction to this idea.
  45  */
  46 struct nexthop_group {
  47         struct nexthop *nexthop;
  48
  49         struct nhg_resilience nhgr;
  50 };
  51
  52 struct nexthop_group *nexthop_group_new(void);
  53 void nexthop_group_delete(struct nexthop_group **nhg);
  54
  55 void nexthop_group_copy(struct nexthop_group *to,
  56                         const struct nexthop_group *from);
  57
  58 /*
  59  * Copy a list of nexthops in 'nh' to an nhg, enforcing canonical sort order
  60  */
  61 void nexthop_group_copy_nh_sorted(struct nexthop_group *nhg,
  62                                   const struct nexthop *nh);
  63
  64 void copy_nexthops(struct nexthop **tnh, const struct nexthop *nh,
  65                    struct nexthop *rparent);
  66
  67 uint32_t nexthop_group_hash_no_recurse(const struct nexthop_group *nhg);
  68 uint32_t nexthop_group_hash(const struct nexthop_group *nhg);
  69 void nexthop_group_mark_duplicates(struct nexthop_group *nhg);
  70
  71 /* Add a nexthop to a list, enforcing the canonical sort order. */
  72 void nexthop_group_add_sorted(struct nexthop_group *nhg,
  73                               struct nexthop *nexthop);
  74
  75 /* The following for loop allows to iterate over the nexthop
  76  * structure of routes.
  77  *
  78  * head:      The pointer to the first nexthop in the chain.
  79  *
  80  * nexthop:   The pointer to the current nexthop, either in the
  81  *            top-level chain or in a resolved chain.
  82  */
  83 #define ALL_NEXTHOPS(head, nhop)                                        \
  84         (nhop) = (head.nexthop);                                        \
  85         (nhop);                                                         \
  86         (nhop) = nexthop_next(nhop)
  87
  88 #define ALL_NEXTHOPS_PTR(head, nhop)                                    \
  89         (nhop) = ((head)->nexthop);                                     \
  90         (nhop);                                                         \
  91         (nhop) = nexthop_next(nhop)
  92
  93
  94 #define NHGC_NAME_SIZE 80
  95
  96 struct nexthop_group_cmd {
  97
  98         RB_ENTRY(nexthop_group_cmd) nhgc_entry;
  99
 100         char name[NHGC_NAME_SIZE];
 101
 102         /* Name of group containing backup nexthops (if set) */
 103         char backup_list_name[NHGC_NAME_SIZE];
 104
 105         struct nexthop_group nhg;
 106
 107         struct list *nhg_list;
 108
 109         QOBJ_FIELDS;
 110 };
 111 RB_HEAD(nhgc_entry_head, nexthp_group_cmd);
 112 RB_PROTOTYPE(nhgc_entry_head, nexthop_group_cmd, nhgc_entry,
 113              nexthop_group_cmd_compare)
 114 DECLARE_QOBJ_TYPE(nexthop_group_cmd);
 115
 116 /*
 117  * Initialize nexthop_groups.  If you are interested in when
 118  * a nexthop_group is added/deleted/modified, then set the
 119  * appropriate callback functions to handle it in your
 120  * code
 121  *
 122  * create - The creation of the nexthop group
 123  * modify - Modification of the nexthop group when not changing a nexthop
 124  *          ( resilience as an example )
 125  * add_nexthop - A nexthop is added to the NHG
 126  * del_nexthop - A nexthop is deleted from the NHG
 127  * destroy - The NHG is deleted
 128  */
 129 void nexthop_group_init(
 130         void (*create)(const char *name),
 131         void (*modify)(const struct nexthop_group_cmd *nhgc),
 132         void (*add_nexthop)(const struct nexthop_group_cmd *nhgc,
 133                             const struct nexthop *nhop),
 134         void (*del_nexthop)(const struct nexthop_group_cmd *nhgc,
 135                             const struct nexthop *nhop),
 136         void (*destroy)(const char *name));
 137
 138 void nexthop_group_enable_vrf(struct vrf *vrf);
 139 void nexthop_group_disable_vrf(struct vrf *vrf);
 140 void nexthop_group_interface_state_change(struct interface *ifp,
 141                                           ifindex_t oldifindex);
 142
 143 extern struct nexthop *nexthop_exists(const struct nexthop_group *nhg,
 144                                       const struct nexthop *nh);
 145 /* This assumes ordered */
 146 extern bool nexthop_group_equal_no_recurse(const struct nexthop_group *nhg1,
 147                                            const struct nexthop_group *nhg2);
 148
 149 /* This assumes ordered */
 150 extern bool nexthop_group_equal(const struct nexthop_group *nhg1,
 151                                 const struct nexthop_group *nhg2);
 152
 153 extern struct nexthop_group_cmd *nhgc_find(const char *name);
 154
 155 extern void nexthop_group_write_nexthop_simple(struct vty *vty,
 156                                                const struct nexthop *nh,
 157                                                char *altifname);
 158 extern void nexthop_group_write_nexthop(struct vty *vty,
 159                                         const struct nexthop *nh);
 160
 161 extern void nexthop_group_json_nexthop(json_object *j,
 162                                        const struct nexthop *nh);
 163
 164 /* Return the number of nexthops in this nhg */
 165 extern uint8_t nexthop_group_nexthop_num(const struct nexthop_group *nhg);
 166 extern uint8_t
 167 nexthop_group_nexthop_num_no_recurse(const struct nexthop_group *nhg);
 168 extern uint8_t
 169 nexthop_group_active_nexthop_num(const struct nexthop_group *nhg);
 170 extern uint8_t
 171 nexthop_group_active_nexthop_num_no_recurse(const struct nexthop_group *nhg);
 172
 173 #ifdef __cplusplus
 174 }
 175 #endif
 176
 177 #endif