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) : ((type) | 1)
  57
  58 /* Nexthop label structure. */
  59 struct nexthop_label {
  60         u_int8_t num_labels;
  61         u_int8_t reserved[3];
  62         mpls_label_t label[0]; /* 1 or more labels. */
  63 };
  64
  65 /* Nexthop structure. */
  66 struct nexthop {
  67         struct nexthop *next;
  68         struct nexthop *prev;
  69
  70         /* Interface index. */
  71         ifindex_t ifindex;
  72
  73         enum nexthop_types_t type;
  74
  75         u_char flags;
  76 #define NEXTHOP_FLAG_ACTIVE     (1 << 0) /* This nexthop is alive. */
  77 #define NEXTHOP_FLAG_FIB        (1 << 1) /* FIB nexthop. */
  78 #define NEXTHOP_FLAG_RECURSIVE  (1 << 2) /* Recursive nexthop. */
  79 #define NEXTHOP_FLAG_ONLINK     (1 << 3) /* Nexthop should be installed onlink. */
  80 #define NEXTHOP_FLAG_MATCHED    (1 << 4) /* Already matched vs a nexthop */
  81 #define NEXTHOP_FLAG_FILTERED   (1 << 5) /* rmap filtered, used by static only */
  82 #define NEXTHOP_FLAG_DUPLICATE  (1 << 6) /* nexthop duplicates another active one */
  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 nexthop_label *nh_label;
 110 };
 111
 112 /* The following for loop allows to iterate over the nexthop
 113  * structure of routes.
 114  *
 115  * head:      The pointer to the first nexthop in the chain.
 116  *
 117  * nexthop:   The pointer to the current nexthop, either in the
 118  *            top-level chain or in a resolved chain.
 119  */
 120 #define ALL_NEXTHOPS(head, nexthop)                                            \
 121         (nexthop) = (head);                                                    \
 122         (nexthop);                                                             \
 123         (nexthop) = nexthop_next(nexthop)
 124
 125 extern int zebra_rnh_ip_default_route;
 126 extern int zebra_rnh_ipv6_default_route;
 127
 128 static inline int nh_resolve_via_default(int family)
 129 {
 130         if (((family == AF_INET) && zebra_rnh_ip_default_route)
 131             || ((family == AF_INET6) && zebra_rnh_ipv6_default_route))
 132                 return 1;
 133         else
 134                 return 0;
 135 }
 136
 137 struct nexthop *nexthop_new(void);
 138 void nexthop_add(struct nexthop **target, struct nexthop *nexthop);
 139
 140 void copy_nexthops(struct nexthop **tnh, struct nexthop *nh,
 141                    struct nexthop *rparent);
 142 void nexthop_free(struct nexthop *nexthop);
 143 void nexthops_free(struct nexthop *nexthop);
 144
 145 void nexthop_add_labels(struct nexthop *, enum lsp_types_t, u_int8_t,
 146                         mpls_label_t *);
 147 void nexthop_del_labels(struct nexthop *);
 148
 149 extern const char *nexthop_type_to_str(enum nexthop_types_t nh_type);
 150 extern int nexthop_same_no_recurse(const struct nexthop *next1,
 151                                    const struct nexthop *next2);
 152 extern int nexthop_labels_match(struct nexthop *nh1, struct nexthop *nh2);
 153 extern int nexthop_same_firsthop (struct nexthop *next1, struct nexthop *next2);
 154
 155 extern const char *nexthop2str(struct nexthop *nexthop, char *str, int size);
 156 extern struct nexthop *nexthop_next(struct nexthop *nexthop);
 157 extern unsigned int nexthop_level(struct nexthop *nexthop);
 158 #endif /*_LIB_NEXTHOP_H */