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 enum isis_tilfa_sid_type {
  24         TILFA_SID_PREFIX = 1,
  25         TILFA_SID_ADJ,
  26 };
  27
  28 struct isis_tilfa_sid {
  29         enum isis_tilfa_sid_type type;
  30         union {
  31                 uint32_t index;
  32                 mpls_label_t label;
  33         } value;
  34 };
  35
  36 RB_HEAD(isis_spf_nodes, isis_spf_node);
  37 RB_PROTOTYPE(isis_spf_nodes, isis_spf_node, entry, isis_spf_node_compare)
  38 struct isis_spf_node {
  39         RB_ENTRY(isis_spf_node) entry;
  40
  41         /* Node's System ID. */
  42         uint8_t sysid[ISIS_SYS_ID_LEN];
  43
  44         /* Local adjacencies over which this node is reachable. */
  45         struct list *adjacencies;
  46
  47         /* Best metric of all adjacencies used to reach this node. */
  48         uint32_t best_metric;
  49
  50         struct {
  51                 /* Node's forward SPT. */
  52                 struct isis_spftree *spftree;
  53
  54                 /* Node's reverse SPT. */
  55                 struct isis_spftree *spftree_reverse;
  56
  57                 /* Node's P-space. */
  58                 struct isis_spf_nodes p_space;
  59         } lfa;
  60 };
  61
  62 enum lfa_protection_type {
  63         LFA_LINK_PROTECTION = 1,
  64         LFA_NODE_PROTECTION,
  65 };
  66
  67 struct lfa_protected_resource {
  68         /* The protection type. */
  69         enum lfa_protection_type type;
  70
  71         /* The protected adjacency (might be a pseudonode). */
  72         uint8_t adjacency[ISIS_SYS_ID_LEN + 1];
  73
  74         /* List of nodes reachable over the protected interface. */
  75         struct isis_spf_nodes nodes;
  76 };
  77
  78 /* Forward declaration(s). */
  79 struct isis_vertex;
  80
  81 /* Prototypes. */
  82 void isis_spf_node_list_init(struct isis_spf_nodes *nodes);
  83 void isis_spf_node_list_clear(struct isis_spf_nodes *nodes);
  84 struct isis_spf_node *isis_spf_node_new(struct isis_spf_nodes *nodes,
  85                                         const uint8_t *sysid);
  86 struct isis_spf_node *isis_spf_node_find(const struct isis_spf_nodes *nodes,
  87                                          const uint8_t *sysid);
  88 bool isis_lfa_excise_adj_check(const struct isis_spftree *spftree,
  89                                const uint8_t *id);
  90 bool isis_lfa_excise_node_check(const struct isis_spftree *spftree,
  91                                 const uint8_t *id);
  92 struct isis_spftree *isis_spf_reverse_run(const struct isis_spftree *spftree);
  93 int isis_spf_run_neighbors(struct isis_spftree *spftree);
  94 void isis_spf_run_lfa(struct isis_area *area, struct isis_spftree *spftree);
  95 int isis_lfa_check(struct isis_spftree *spftree, struct isis_vertex *vertex);
  96 struct isis_spftree *
  97 isis_tilfa_compute(struct isis_area *area, struct isis_spftree *spftree,
  98                    struct isis_spftree *spftree_reverse,
  99                    struct lfa_protected_resource *protected_resource);
 100
 101 #endif /* _FRR_ISIS_LFA_H */