lib/nexthop.h

   1 /*
   2  * Nexthop structure definition.
   3  * Copyright (C) 1997, 98, 99, 2001 Kunihiro Ishiguro
   4  * Copyright (C) 2013 Cumulus Networks, Inc.
   5  *
   6  * This file is part of Quagga.
   7  *
   8  * Quagga is free software; you can redistribute it and/or modify it
   9  * under the terms of the GNU General Public License as published by the
  10  * Free Software Foundation; either version 2, or (at your option) any
  11  * later version.
  12  *
  13  * Quagga is distributed in the hope that it will be useful, but
  14  * WITHOUT ANY WARRANTY; without even the implied warranty of
  15  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
  16  * General Public License for more details.
  17  *
  18  * You should have received a copy of the GNU General Public License along
  19  * with this program; see the file COPYING; if not, write to the Free Software
  20  * Foundation, Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA
  21  */
  22
  23 #ifndef _LIB_NEXTHOP_H
  24 #define _LIB_NEXTHOP_H
  25
  26 #include "prefix.h"
  27 #include "mpls.h"
  28
  29 #ifdef __cplusplus
  30 extern "C" {
  31 #endif
  32
  33 /* Maximum next hop string length - gateway + ifindex */
  34 #define NEXTHOP_STRLEN (INET6_ADDRSTRLEN + 30)
  35
  36 union g_addr {
  37         struct in_addr ipv4;
  38         struct in6_addr ipv6;
  39 };
  40
  41 enum nexthop_types_t {
  42         NEXTHOP_TYPE_IFINDEX = 1,  /* Directly connected.  */
  43         NEXTHOP_TYPE_IPV4,       /* IPv4 nexthop.  */
  44         NEXTHOP_TYPE_IPV4_IFINDEX, /* IPv4 nexthop with ifindex.  */
  45         NEXTHOP_TYPE_IPV6,       /* IPv6 nexthop.  */
  46         NEXTHOP_TYPE_IPV6_IFINDEX, /* IPv6 nexthop with ifindex.  */
  47         NEXTHOP_TYPE_BLACKHOLE,    /* Null0 nexthop.  */
  48 };
  49
  50 enum blackhole_type {
  51         BLACKHOLE_UNSPEC = 0,
  52         BLACKHOLE_NULL,
  53         BLACKHOLE_REJECT,
  54         BLACKHOLE_ADMINPROHIB,
  55 };
  56
  57 /* IPV[46] -> IPV[46]_IFINDEX */
  58 #define NEXTHOP_FIRSTHOPTYPE(type)                                             \
  59         ((type) == NEXTHOP_TYPE_IFINDEX || (type) == NEXTHOP_TYPE_BLACKHOLE)   \
  60                 ? (type)                                                       \
  61                 : ((type) | 1)
  62
  63 /* Nexthop structure. */
  64 struct nexthop {
  65         struct nexthop *next;
  66         struct nexthop *prev;
  67
  68         /*
  69          * What vrf is this nexthop associated with?
  70          */
  71         vrf_id_t vrf_id;
  72
  73         /* Interface index. */
  74         ifindex_t ifindex;
  75
  76         enum nexthop_types_t type;
  77
  78         uint8_t flags;
  79 #define NEXTHOP_FLAG_ACTIVE     (1 << 0) /* This nexthop is alive. */
  80 #define NEXTHOP_FLAG_FIB        (1 << 1) /* FIB nexthop. */
  81 #define NEXTHOP_FLAG_RECURSIVE  (1 << 2) /* Recursive nexthop. */
  82 #define NEXTHOP_FLAG_ONLINK     (1 << 3) /* Nexthop should be installed onlink. */
  83 #define NEXTHOP_FLAG_MATCHED    (1 << 4) /* Already matched vs a nexthop */
  84 #define NEXTHOP_FLAG_DUPLICATE  (1 << 5) /* nexthop duplicates another active one */
  85 #define NEXTHOP_FLAG_RNH_FILTERED  (1 << 6) /* rmap filtered, used by rnh */
  86 #define NEXTHOP_IS_ACTIVE(flags)                                               \
  87         (CHECK_FLAG(flags, NEXTHOP_FLAG_ACTIVE)                                \
  88          && !CHECK_FLAG(flags, NEXTHOP_FLAG_DUPLICATE))
  89
  90         /* Nexthop address */
  91         union {
  92                 union g_addr gate;
  93                 enum blackhole_type bh_type;
  94         };
  95         union g_addr src;
  96         union g_addr rmap_src; /* Src is set via routemap */
  97
  98         /* Nexthops obtained by recursive resolution.
  99          *
 100          * If the nexthop struct needs to be resolved recursively,
 101          * NEXTHOP_FLAG_RECURSIVE will be set in flags and the nexthops
 102          * obtained by recursive resolution will be added to `resolved'.
 103          */
 104         struct nexthop *resolved;
 105         /* Recursive parent */
 106         struct nexthop *rparent;
 107
 108         /* Type of label(s), if any */
 109         enum lsp_types_t nh_label_type;
 110
 111         /* Label(s) associated with this nexthop. */
 112         struct mpls_label_stack *nh_label;
 113 };
 114
 115 struct nexthop *nexthop_new(void);
 116
 117 void nexthop_free(struct nexthop *nexthop);
 118 void nexthops_free(struct nexthop *nexthop);
 119
 120 void nexthop_add_labels(struct nexthop *, enum lsp_types_t, uint8_t,
 121                         mpls_label_t *);
 122 void nexthop_del_labels(struct nexthop *);
 123
 124 /*
 125  * Hash a nexthop. Suitable for use with hash tables.
 126  *
 127  * This function uses the following values when computing the hash:
 128  * - vrf_id
 129  * - ifindex
 130  * - type
 131  * - gate
 132  *
 133  * nexthop
 134  *    The nexthop to hash
 135  *
 136  * Returns:
 137  *    32-bit hash of nexthop
 138  */
 139 uint32_t nexthop_hash(const struct nexthop *nexthop);
 140
 141 extern bool nexthop_same(const struct nexthop *nh1, const struct nexthop *nh2);
 142 extern bool nexthop_same_no_labels(const struct nexthop *nh1,
 143                                    const struct nexthop *nh2);
 144 extern int nexthop_cmp(const struct nexthop *nh1, const struct nexthop *nh2);
 145
 146 extern const char *nexthop_type_to_str(enum nexthop_types_t nh_type);
 147 extern bool nexthop_labels_match(const struct nexthop *nh1,
 148                                  const struct nexthop *nh2);
 149 extern int nexthop_same_firsthop(struct nexthop *next1, struct nexthop *next2);
 150
 151 extern const char *nexthop2str(const struct nexthop *nexthop,
 152                                char *str, int size);
 153 extern struct nexthop *nexthop_next(struct nexthop *nexthop);
 154 extern unsigned int nexthop_level(struct nexthop *nexthop);
 155
 156 #ifdef __cplusplus
 157 }
 158 #endif
 159
 160 #endif /*_LIB_NEXTHOP_H */