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 structure. */
  59 struct nexthop {
  60         struct nexthop *next;
  61         struct nexthop *prev;
  62
  63         /* Interface index. */
  64         ifindex_t ifindex;
  65
  66         enum nexthop_types_t type;
  67
  68         u_char flags;
  69 #define NEXTHOP_FLAG_ACTIVE     (1 << 0) /* This nexthop is alive. */
  70 #define NEXTHOP_FLAG_FIB        (1 << 1) /* FIB nexthop. */
  71 #define NEXTHOP_FLAG_RECURSIVE  (1 << 2) /* Recursive nexthop. */
  72 #define NEXTHOP_FLAG_ONLINK     (1 << 3) /* Nexthop should be installed onlink. */
  73 #define NEXTHOP_FLAG_MATCHED    (1 << 4) /* Already matched vs a nexthop */
  74 #define NEXTHOP_FLAG_FILTERED   (1 << 5) /* rmap filtered, used by static only */
  75 #define NEXTHOP_FLAG_DUPLICATE  (1 << 6) /* nexthop duplicates another active one */
  76 #define NEXTHOP_FLAG_EVPN_RVTEP (1 << 7) /* EVPN remote vtep nexthop */
  77 #define NEXTHOP_IS_ACTIVE(flags) \
  78         (CHECK_FLAG(flags, NEXTHOP_FLAG_ACTIVE) \
  79                 && !CHECK_FLAG(flags, NEXTHOP_FLAG_DUPLICATE))
  80
  81         /* Nexthop address */
  82         union {
  83                 union g_addr gate;
  84                 enum blackhole_type bh_type;
  85         };
  86         union g_addr src;
  87         union g_addr rmap_src; /* Src is set via routemap */
  88
  89         /* Nexthops obtained by recursive resolution.
  90          *
  91          * If the nexthop struct needs to be resolved recursively,
  92          * NEXTHOP_FLAG_RECURSIVE will be set in flags and the nexthops
  93          * obtained by recursive resolution will be added to `resolved'.
  94          */
  95         struct nexthop *resolved;
  96         /* Recursive parent */
  97         struct nexthop *rparent;
  98
  99         /* Type of label(s), if any */
 100         enum lsp_types_t nh_label_type;
 101
 102         /* Label(s) associated with this nexthop. */
 103         struct mpls_label_stack *nh_label;
 104 };
 105
 106 /* The following for loop allows to iterate over the nexthop
 107  * structure of routes.
 108  *
 109  * head:      The pointer to the first nexthop in the chain.
 110  *
 111  * nexthop:   The pointer to the current nexthop, either in the
 112  *            top-level chain or in a resolved chain.
 113  */
 114 #define ALL_NEXTHOPS(head, nexthop)                                            \
 115         (nexthop) = (head);                                                    \
 116         (nexthop);                                                             \
 117         (nexthop) = nexthop_next(nexthop)
 118
 119 extern int zebra_rnh_ip_default_route;
 120 extern int zebra_rnh_ipv6_default_route;
 121
 122 static inline int nh_resolve_via_default(int family)
 123 {
 124         if (((family == AF_INET) && zebra_rnh_ip_default_route)
 125             || ((family == AF_INET6) && zebra_rnh_ipv6_default_route))
 126                 return 1;
 127         else
 128                 return 0;
 129 }
 130
 131 struct nexthop *nexthop_new(void);
 132 void nexthop_add(struct nexthop **target, struct nexthop *nexthop);
 133
 134 void copy_nexthops(struct nexthop **tnh, struct nexthop *nh,
 135                    struct nexthop *rparent);
 136 void nexthop_free(struct nexthop *nexthop);
 137 void nexthops_free(struct nexthop *nexthop);
 138
 139 void nexthop_add_labels(struct nexthop *, enum lsp_types_t, u_int8_t,
 140                         mpls_label_t *);
 141 void nexthop_del_labels(struct nexthop *);
 142
 143 extern const char *nexthop_type_to_str(enum nexthop_types_t nh_type);
 144 extern int nexthop_same_no_recurse(const struct nexthop *next1,
 145                                    const struct nexthop *next2);
 146 extern int nexthop_labels_match(struct nexthop *nh1, struct nexthop *nh2);
 147 extern int nexthop_same_firsthop (struct nexthop *next1, struct nexthop *next2);
 148
 149 extern const char *nexthop2str(struct nexthop *nexthop, char *str, int size);
 150 extern struct nexthop *nexthop_next(struct nexthop *nexthop);
 151 extern unsigned int nexthop_level(struct nexthop *nexthop);
 152 #endif /*_LIB_NEXTHOP_H */