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
  26 #ifdef __cplusplus
  27 extern "C" {
  28 #endif
  29
  30 /*
  31  * What is a nexthop group?
  32  *
  33  * A nexthop group is a collection of nexthops that make up
  34  * the ECMP path for the route.
  35  *
  36  * This module provides a proper abstraction to this idea.
  37  */
  38 struct nexthop_group {
  39         struct nexthop *nexthop;
  40 };
  41
  42 struct nexthop_group *nexthop_group_new(void);
  43 void nexthop_group_delete(struct nexthop_group **nhg);
  44
  45 void nexthop_add(struct nexthop **target, struct nexthop *nexthop);
  46 void nexthop_del(struct nexthop_group *nhg, struct nexthop *nexthop);
  47 void copy_nexthops(struct nexthop **tnh, const struct nexthop *nh,
  48                    struct nexthop *rparent);
  49
  50 uint32_t nexthop_group_hash(const struct nexthop_group *nhg);
  51
  52 /* The following for loop allows to iterate over the nexthop
  53  * structure of routes.
  54  *
  55  * head:      The pointer to the first nexthop in the chain.
  56  *
  57  * nexthop:   The pointer to the current nexthop, either in the
  58  *            top-level chain or in a resolved chain.
  59  */
  60 #define ALL_NEXTHOPS(head, nhop)                                        \
  61         (nhop) = (head.nexthop);                                        \
  62         (nhop);                                                         \
  63         (nhop) = nexthop_next(nhop)
  64
  65 #define ALL_NEXTHOPS_PTR(head, nhop)                                    \
  66         (nhop) = ((head)->nexthop);                                     \
  67         (nhop);                                                         \
  68         (nhop) = nexthop_next(nhop)
  69
  70
  71 struct nexthop_hold {
  72         char *nhvrf_name;
  73         union sockunion *addr;
  74         char *intf;
  75 };
  76
  77 struct nexthop_group_cmd {
  78
  79         RB_ENTRY(nexthop_group_cmd) nhgc_entry;
  80
  81         char name[80];
  82
  83         struct nexthop_group nhg;
  84
  85         struct list *nhg_list;
  86
  87         QOBJ_FIELDS
  88 };
  89 RB_HEAD(nhgc_entry_head, nexthp_group_cmd);
  90 RB_PROTOTYPE(nhgc_entry_head, nexthop_group_cmd, nhgc_entry,
  91              nexthop_group_cmd_compare)
  92 DECLARE_QOBJ_TYPE(nexthop_group_cmd)
  93
  94 /*
  95  * Initialize nexthop_groups.  If you are interested in when
  96  * a nexthop_group is added/deleted/modified, then set the
  97  * appropriate callback functions to handle it in your
  98  * code
  99  */
 100 void nexthop_group_init(
 101         void (*create)(const char *name),
 102         void (*add_nexthop)(const struct nexthop_group_cmd *nhgc,
 103                             const struct nexthop *nhop),
 104         void (*del_nexthop)(const struct nexthop_group_cmd *nhgc,
 105                             const struct nexthop *nhop),
 106         void (*destroy)(const char *name));
 107
 108 void nexthop_group_enable_vrf(struct vrf *vrf);
 109 void nexthop_group_disable_vrf(struct vrf *vrf);
 110 void nexthop_group_interface_state_change(struct interface *ifp,
 111                                           ifindex_t oldifindex);
 112
 113 extern struct nexthop *nexthop_exists(struct nexthop_group *nhg,
 114                                       struct nexthop *nh);
 115
 116 extern struct nexthop_group_cmd *nhgc_find(const char *name);
 117
 118 extern void nexthop_group_write_nexthop(struct vty *vty, struct nexthop *nh);
 119
 120 /* Return the number of nexthops in this nhg */
 121 extern uint8_t nexthop_group_nexthop_num(const struct nexthop_group *nhg);
 122 extern uint8_t
 123 nexthop_group_active_nexthop_num(const struct nexthop_group *nhg);
 124
 125 #ifdef __cplusplus
 126 }
 127 #endif
 128
 129 #endif