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 /* Maximum next hop string length - gateway + ifindex */
  30 #define NEXTHOP_STRLEN (INET6_ADDRSTRLEN + 30)
  31
  32 union g_addr {
  33         struct in_addr ipv4;
  34         struct in6_addr ipv6;
  35 };
  36
  37 enum nexthop_types_t {
  38         NEXTHOP_TYPE_IFINDEX = 1,  /* Directly connected.  */
  39         NEXTHOP_TYPE_IPV4,       /* IPv4 nexthop.  */
  40         NEXTHOP_TYPE_IPV4_IFINDEX, /* IPv4 nexthop with ifindex.  */
  41         NEXTHOP_TYPE_IPV6,       /* IPv6 nexthop.  */
  42         NEXTHOP_TYPE_IPV6_IFINDEX, /* IPv6 nexthop with ifindex.  */
  43         NEXTHOP_TYPE_BLACKHOLE,    /* Null0 nexthop.  */
  44 };
  45
  46 enum blackhole_type {
  47         BLACKHOLE_UNSPEC = 0,
  48         BLACKHOLE_NULL,
  49         BLACKHOLE_REJECT,
  50         BLACKHOLE_ADMINPROHIB,
  51 };
  52
  53 /* IPV[46] -> IPV[46]_IFINDEX */
  54 #define NEXTHOP_FIRSTHOPTYPE(type)                                             \
  55         ((type) == NEXTHOP_TYPE_IFINDEX || (type) == NEXTHOP_TYPE_BLACKHOLE)   \
  56                 ? (type)                                                       \
  57                 : ((type) | 1)
  58
  59 /* Nexthop structure. */
  60 struct nexthop {
  61         struct nexthop *next;
  62         struct nexthop *prev;
  63
  64         /*
  65          * What vrf is this nexthop associated with?
  66          */
  67         vrf_id_t vrf_id;
  68
  69         /* Interface index. */
  70         ifindex_t ifindex;
  71
  72         enum nexthop_types_t type;
  73
  74         uint8_t flags;
  75 #define NEXTHOP_FLAG_ACTIVE     (1 << 0) /* This nexthop is alive. */
  76 #define NEXTHOP_FLAG_FIB        (1 << 1) /* FIB nexthop. */
  77 #define NEXTHOP_FLAG_RECURSIVE  (1 << 2) /* Recursive nexthop. */
  78 #define NEXTHOP_FLAG_ONLINK     (1 << 3) /* Nexthop should be installed onlink. */
  79 #define NEXTHOP_FLAG_MATCHED    (1 << 4) /* Already matched vs a nexthop */
  80 #define NEXTHOP_FLAG_FILTERED   (1 << 5) /* rmap filtered, used by static only */
  81 #define NEXTHOP_FLAG_DUPLICATE  (1 << 6) /* nexthop duplicates another active one */
  82 #define NEXTHOP_FLAG_EVPN_RVTEP (1 << 7) /* EVPN remote vtep nexthop */
  83 #define NEXTHOP_IS_ACTIVE(flags)                                               \
  84         (CHECK_FLAG(flags, NEXTHOP_FLAG_ACTIVE)                                \
  85          && !CHECK_FLAG(flags, NEXTHOP_FLAG_DUPLICATE))
  86
  87         /* Nexthop address */
  88         union {
  89                 union g_addr gate;
  90                 enum blackhole_type bh_type;
  91         };
  92         union g_addr src;
  93         union g_addr rmap_src; /* Src is set via routemap */
  94
  95         /* Nexthops obtained by recursive resolution.
  96          *
  97          * If the nexthop struct needs to be resolved recursively,
  98          * NEXTHOP_FLAG_RECURSIVE will be set in flags and the nexthops
  99          * obtained by recursive resolution will be added to `resolved'.
 100          */
 101         struct nexthop *resolved;
 102         /* Recursive parent */
 103         struct nexthop *rparent;
 104
 105         /* Type of label(s), if any */
 106         enum lsp_types_t nh_label_type;
 107
 108         /* Label(s) associated with this nexthop. */
 109         struct mpls_label_stack *nh_label;
 110 };
 111
 112 struct nexthop *nexthop_new(void);
 113
 114 void nexthop_free(struct nexthop *nexthop);
 115 void nexthops_free(struct nexthop *nexthop);
 116
 117 void nexthop_add_labels(struct nexthop *, enum lsp_types_t, uint8_t,
 118                         mpls_label_t *);
 119 void nexthop_del_labels(struct nexthop *);
 120
 121 /*
 122  * Hash a nexthop. Suitable for use with hash tables.
 123  *
 124  * This function uses the following values when computing the hash:
 125  * - vrf_id
 126  * - ifindex
 127  * - type
 128  * - gate
 129  *
 130  * nexthop
 131  *    The nexthop to hash
 132  *
 133  * Returns:
 134  *    32-bit hash of nexthop
 135  */
 136 uint32_t nexthop_hash(struct nexthop *nexthop);
 137
 138 extern bool nexthop_same(const struct nexthop *nh1, const struct nexthop *nh2);
 139
 140 extern const char *nexthop_type_to_str(enum nexthop_types_t nh_type);
 141 extern int nexthop_same_no_recurse(const struct nexthop *next1,
 142                                    const struct nexthop *next2);
 143 extern int nexthop_labels_match(struct nexthop *nh1, struct nexthop *nh2);
 144 extern int nexthop_same_firsthop(struct nexthop *next1, struct nexthop *next2);
 145
 146 extern const char *nexthop2str(const struct nexthop *nexthop, char *str, int size);
 147 extern struct nexthop *nexthop_next(struct nexthop *nexthop);
 148 extern unsigned int nexthop_level(struct nexthop *nexthop);
 149 #endif /*_LIB_NEXTHOP_H */