isisd/isis_lfa.h

   1 /*
   2  * Copyright (C) 2020  NetDEF, Inc.
   3  *                     Renato Westphal
   4  *
   5  * This program is free software; you can redistribute it and/or modify it
   6  * under the terms of the GNU General Public License as published by the Free
   7  * Software Foundation; either version 2 of the License, or (at your option)
   8  * any later version.
   9  *
  10  * This program is distributed in the hope that it will be useful, but WITHOUT
  11  * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
  12  * FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License for
  13  * more details.
  14  *
  15  * You should have received a copy of the GNU General Public License along
  16  * with this program; see the file COPYING; if not, write to the Free Software
  17  * Foundation, Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA
  18  */
  19
  20 #ifndef _FRR_ISIS_LFA_H
  21 #define _FRR_ISIS_LFA_H
  22
  23 #include "lib/typesafe.h"
  24
  25 PREDECL_RBTREE_UNIQ(lfa_tiebreaker_tree)
  26
  27 enum lfa_tiebreaker_type {
  28         LFA_TIEBREAKER_DOWNSTREAM = 0,
  29         LFA_TIEBREAKER_LOWEST_METRIC,
  30         LFA_TIEBREAKER_NODE_PROTECTING,
  31 };
  32
  33 struct lfa_tiebreaker {
  34         struct lfa_tiebreaker_tree_item entry;
  35         uint8_t index;
  36         enum lfa_tiebreaker_type type;
  37         struct isis_area *area;
  38 };
  39 int lfa_tiebreaker_cmp(const struct lfa_tiebreaker *a,
  40                        const struct lfa_tiebreaker *b);
  41 DECLARE_RBTREE_UNIQ(lfa_tiebreaker_tree, struct lfa_tiebreaker, entry,
  42                     lfa_tiebreaker_cmp)
  43
  44 enum isis_tilfa_sid_type {
  45         TILFA_SID_PREFIX = 1,
  46         TILFA_SID_ADJ,
  47 };
  48
  49 struct isis_tilfa_sid {
  50         enum isis_tilfa_sid_type type;
  51         union {
  52                 struct {
  53                         uint32_t value;
  54                         bool remote;
  55                         uint8_t remote_sysid[ISIS_SYS_ID_LEN];
  56                 } index;
  57                 mpls_label_t label;
  58         } value;
  59 };
  60
  61 enum spf_prefix_priority {
  62         SPF_PREFIX_PRIO_CRITICAL = 0,
  63         SPF_PREFIX_PRIO_HIGH,
  64         SPF_PREFIX_PRIO_MEDIUM,
  65         SPF_PREFIX_PRIO_LOW,
  66         SPF_PREFIX_PRIO_MAX,
  67 };
  68
  69 struct spf_prefix_priority_acl {
  70         char *name;
  71         struct access_list *list_v4;
  72         struct access_list *list_v6;
  73 };
  74
  75 RB_HEAD(isis_spf_nodes, isis_spf_node);
  76 RB_PROTOTYPE(isis_spf_nodes, isis_spf_node, entry, isis_spf_node_compare)
  77 struct isis_spf_node {
  78         RB_ENTRY(isis_spf_node) entry;
  79
  80         /* Node's System ID. */
  81         uint8_t sysid[ISIS_SYS_ID_LEN];
  82
  83         /* Local adjacencies over which this node is reachable. */
  84         struct list *adjacencies;
  85
  86         /* Best metric of all adjacencies used to reach this node. */
  87         uint32_t best_metric;
  88
  89         struct {
  90                 /* Node's forward SPT. */
  91                 struct isis_spftree *spftree;
  92
  93                 /* Node's reverse SPT. */
  94                 struct isis_spftree *spftree_reverse;
  95
  96                 /* Node's P-space. */
  97                 struct isis_spf_nodes p_space;
  98         } lfa;
  99 };
 100
 101 enum lfa_protection_type {
 102         LFA_LINK_PROTECTION = 1,
 103         LFA_NODE_PROTECTION,
 104 };
 105
 106 struct lfa_protected_resource {
 107         /* The protection type. */
 108         enum lfa_protection_type type;
 109
 110         /* The protected adjacency (might be a pseudonode). */
 111         uint8_t adjacency[ISIS_SYS_ID_LEN + 1];
 112
 113         /* List of nodes reachable over the protected interface. */
 114         struct isis_spf_nodes nodes;
 115 };
 116
 117 /* Forward declaration(s). */
 118 struct isis_vertex;
 119
 120 /* Prototypes. */
 121 void isis_spf_node_list_init(struct isis_spf_nodes *nodes);
 122 void isis_spf_node_list_clear(struct isis_spf_nodes *nodes);
 123 struct isis_spf_node *isis_spf_node_new(struct isis_spf_nodes *nodes,
 124                                         const uint8_t *sysid);
 125 struct isis_spf_node *isis_spf_node_find(const struct isis_spf_nodes *nodes,
 126                                          const uint8_t *sysid);
 127 void isis_lfa_tiebreakers_init(struct isis_area *area, int level);
 128 void isis_lfa_tiebreakers_clear(struct isis_area *area, int level);
 129 struct lfa_tiebreaker *isis_lfa_tiebreaker_add(struct isis_area *area,
 130                                                int level, uint8_t index,
 131                                                enum lfa_tiebreaker_type type);
 132 void isis_lfa_tiebreaker_delete(struct isis_area *area, int level,
 133                                 struct lfa_tiebreaker *tie_b);
 134 void isis_lfa_excluded_ifaces_init(struct isis_circuit *circuit, int level);
 135 void isis_lfa_excluded_ifaces_clear(struct isis_circuit *circuit, int level);
 136 void isis_lfa_excluded_iface_add(struct isis_circuit *circuit, int level,
 137                                  const char *ifname);
 138 void isis_lfa_excluded_iface_delete(struct isis_circuit *circuit, int level,
 139                                     const char *ifname);
 140 bool isis_lfa_excluded_iface_check(struct isis_circuit *circuit, int level,
 141                                    const char *ifname);
 142 bool isis_lfa_excise_adj_check(const struct isis_spftree *spftree,
 143                                const uint8_t *id);
 144 bool isis_lfa_excise_node_check(const struct isis_spftree *spftree,
 145                                 const uint8_t *id);
 146 struct isis_spftree *isis_spf_reverse_run(const struct isis_spftree *spftree);
 147 int isis_spf_run_neighbors(struct isis_spftree *spftree);
 148 void isis_lfa_compute(struct isis_area *area, struct isis_circuit *circuit,
 149                       struct isis_spftree *spftree,
 150                       struct lfa_protected_resource *resource);
 151 void isis_spf_run_lfa(struct isis_area *area, struct isis_spftree *spftree);
 152 int isis_tilfa_check(struct isis_spftree *spftree, struct isis_vertex *vertex);
 153 struct isis_spftree *
 154 isis_tilfa_compute(struct isis_area *area, struct isis_spftree *spftree,
 155                    struct isis_spftree *spftree_reverse,
 156                    struct lfa_protected_resource *protected_resource);
 157
 158 #endif /* _FRR_ISIS_LFA_H */