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_group_copy(struct nexthop_group *to,
  46                         struct nexthop_group *from);
  47
  48 /*
  49  * Copy a list of nexthops in 'nh' to an nhg, enforcing canonical sort order
  50  */
  51 void nexthop_group_copy_nh_sorted(struct nexthop_group *nhg,
  52                                   const struct nexthop *nh);
  53
  54 void copy_nexthops(struct nexthop **tnh, const struct nexthop *nh,
  55                    struct nexthop *rparent);
  56
  57 uint32_t nexthop_group_hash_no_recurse(const struct nexthop_group *nhg);
  58 uint32_t nexthop_group_hash(const struct nexthop_group *nhg);
  59 void nexthop_group_mark_duplicates(struct nexthop_group *nhg);
  60 void nexthop_group_add_sorted(struct nexthop_group *nhg,
  61                               struct nexthop *nexthop);
  62
  63 /* The following for loop allows to iterate over the nexthop
  64  * structure of routes.
  65  *
  66  * head:      The pointer to the first nexthop in the chain.
  67  *
  68  * nexthop:   The pointer to the current nexthop, either in the
  69  *            top-level chain or in a resolved chain.
  70  */
  71 #define ALL_NEXTHOPS(head, nhop)                                        \
  72         (nhop) = (head.nexthop);                                        \
  73         (nhop);                                                         \
  74         (nhop) = nexthop_next(nhop)
  75
  76 #define ALL_NEXTHOPS_PTR(head, nhop)                                    \
  77         (nhop) = ((head)->nexthop);                                     \
  78         (nhop);                                                         \
  79         (nhop) = nexthop_next(nhop)
  80
  81
  82 struct nexthop_group_cmd {
  83
  84         RB_ENTRY(nexthop_group_cmd) nhgc_entry;
  85
  86         char name[80];
  87
  88         struct nexthop_group nhg;
  89
  90         struct list *nhg_list;
  91
  92         QOBJ_FIELDS
  93 };
  94 RB_HEAD(nhgc_entry_head, nexthp_group_cmd);
  95 RB_PROTOTYPE(nhgc_entry_head, nexthop_group_cmd, nhgc_entry,
  96              nexthop_group_cmd_compare)
  97 DECLARE_QOBJ_TYPE(nexthop_group_cmd)
  98
  99 /*
 100  * Initialize nexthop_groups.  If you are interested in when
 101  * a nexthop_group is added/deleted/modified, then set the
 102  * appropriate callback functions to handle it in your
 103  * code
 104  */
 105 void nexthop_group_init(
 106         void (*create)(const char *name),
 107         void (*add_nexthop)(const struct nexthop_group_cmd *nhgc,
 108                             const struct nexthop *nhop),
 109         void (*del_nexthop)(const struct nexthop_group_cmd *nhgc,
 110                             const struct nexthop *nhop),
 111         void (*destroy)(const char *name));
 112
 113 void nexthop_group_enable_vrf(struct vrf *vrf);
 114 void nexthop_group_disable_vrf(struct vrf *vrf);
 115 void nexthop_group_interface_state_change(struct interface *ifp,
 116                                           ifindex_t oldifindex);
 117
 118 extern struct nexthop *nexthop_exists(const struct nexthop_group *nhg,
 119                                       const struct nexthop *nh);
 120 /* This assumes ordered */
 121 extern bool nexthop_group_equal_no_recurse(const struct nexthop_group *nhg1,
 122                                            const struct nexthop_group *nhg2);
 123
 124 /* This assumes ordered */
 125 extern bool nexthop_group_equal(const struct nexthop_group *nhg1,
 126                                 const struct nexthop_group *nhg2);
 127
 128 extern struct nexthop_group_cmd *nhgc_find(const char *name);
 129
 130 extern void nexthop_group_write_nexthop(struct vty *vty, struct nexthop *nh);
 131
 132 /* Return the number of nexthops in this nhg */
 133 extern uint8_t nexthop_group_nexthop_num(const struct nexthop_group *nhg);
 134 extern uint8_t
 135 nexthop_group_nexthop_num_no_recurse(const struct nexthop_group *nhg);
 136 extern uint8_t
 137 nexthop_group_active_nexthop_num(const struct nexthop_group *nhg);
 138 extern uint8_t
 139 nexthop_group_active_nexthop_num_no_recurse(const struct nexthop_group *nhg);
 140
 141 #ifdef __cplusplus
 142 }
 143 #endif
 144
 145 #endif