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         /* Weight of the nexthop ( for unequal cost ECMP ) */
 115         uint8_t weight;
 116 };
 117
 118 struct nexthop *nexthop_new(void);
 119
 120 void nexthop_free(struct nexthop *nexthop);
 121 void nexthops_free(struct nexthop *nexthop);
 122
 123 void nexthop_add_labels(struct nexthop *, enum lsp_types_t, uint8_t,
 124                         mpls_label_t *);
 125 void nexthop_del_labels(struct nexthop *);
 126
 127 /*
 128  * Allocate a new nexthop object and initialize it from various args.
 129  */
 130 struct nexthop *nexthop_from_ifindex(ifindex_t ifindex, vrf_id_t vrf_id);
 131 struct nexthop *nexthop_from_ipv4(const struct in_addr *ipv4,
 132                                   const struct in_addr *src,
 133                                   vrf_id_t vrf_id);
 134 struct nexthop *nexthop_from_ipv4_ifindex(const struct in_addr *ipv4,
 135                                           const struct in_addr *src,
 136                                           ifindex_t ifindex, vrf_id_t vrf_id);
 137 struct nexthop *nexthop_from_ipv6(const struct in6_addr *ipv6,
 138                                   vrf_id_t vrf_id);
 139 struct nexthop *nexthop_from_ipv6_ifindex(const struct in6_addr *ipv6,
 140                                           ifindex_t ifindex, vrf_id_t vrf_id);
 141 struct nexthop *nexthop_from_blackhole(enum blackhole_type bh_type);
 142
 143 /*
 144  * Hash a nexthop. Suitable for use with hash tables.
 145  *
 146  * This function uses the following values when computing the hash:
 147  * - vrf_id
 148  * - ifindex
 149  * - type
 150  * - gate
 151  *
 152  * nexthop
 153  *    The nexthop to hash
 154  *
 155  * Returns:
 156  *    32-bit hash of nexthop
 157  */
 158 uint32_t nexthop_hash(const struct nexthop *nexthop);
 159 /*
 160  * Hash a nexthop only on word-sized attributes:
 161  * - vrf_id
 162  * - ifindex
 163  * - type
 164  * - (some) flags
 165  */
 166 uint32_t nexthop_hash_quick(const struct nexthop *nexthop);
 167
 168 extern bool nexthop_same(const struct nexthop *nh1, const struct nexthop *nh2);
 169 extern bool nexthop_same_no_labels(const struct nexthop *nh1,
 170                                    const struct nexthop *nh2);
 171 extern int nexthop_cmp(const struct nexthop *nh1, const struct nexthop *nh2);
 172 extern int nexthop_g_addr_cmp(enum nexthop_types_t type,
 173                               const union g_addr *addr1,
 174                               const union g_addr *addr2);
 175
 176 extern const char *nexthop_type_to_str(enum nexthop_types_t nh_type);
 177 extern bool nexthop_labels_match(const struct nexthop *nh1,
 178                                  const struct nexthop *nh2);
 179 extern int nexthop_same_firsthop(struct nexthop *next1, struct nexthop *next2);
 180
 181 extern const char *nexthop2str(const struct nexthop *nexthop,
 182                                char *str, int size);
 183 extern struct nexthop *nexthop_next(const struct nexthop *nexthop);
 184 extern struct nexthop *
 185 nexthop_next_active_resolved(const struct nexthop *nexthop);
 186 extern unsigned int nexthop_level(struct nexthop *nexthop);
 187 /* Copies to an already allocated nexthop struct */
 188 extern void nexthop_copy(struct nexthop *copy, const struct nexthop *nexthop,
 189                          struct nexthop *rparent);
 190 /* Copies to an already allocated nexthop struct, not including recurse info */
 191 extern void nexthop_copy_no_recurse(struct nexthop *copy,
 192                                     const struct nexthop *nexthop,
 193                                     struct nexthop *rparent);
 194 /* Duplicates a nexthop and returns the newly allocated nexthop */
 195 extern struct nexthop *nexthop_dup(const struct nexthop *nexthop,
 196                                    struct nexthop *rparent);
 197 /* Duplicates a nexthop and returns the newly allocated nexthop */
 198 extern struct nexthop *nexthop_dup_no_recurse(const struct nexthop *nexthop,
 199                                               struct nexthop *rparent);
 200
 201 #ifdef __cplusplus
 202 }
 203 #endif
 204
 205 #endif /*_LIB_NEXTHOP_H */