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 #include "vxlan.h"
  29
  30 #ifdef __cplusplus
  31 extern "C" {
  32 #endif
  33
  34 /* Maximum next hop string length - gateway + ifindex */
  35 #define NEXTHOP_STRLEN (INET6_ADDRSTRLEN + 30)
  36
  37 union g_addr {
  38         struct in_addr ipv4;
  39         struct in6_addr ipv6;
  40 };
  41
  42 enum nexthop_types_t {
  43         NEXTHOP_TYPE_IFINDEX = 1,  /* Directly connected.  */
  44         NEXTHOP_TYPE_IPV4,       /* IPv4 nexthop.  */
  45         NEXTHOP_TYPE_IPV4_IFINDEX, /* IPv4 nexthop with ifindex.  */
  46         NEXTHOP_TYPE_IPV6,       /* IPv6 nexthop.  */
  47         NEXTHOP_TYPE_IPV6_IFINDEX, /* IPv6 nexthop with ifindex.  */
  48         NEXTHOP_TYPE_BLACKHOLE,    /* Null0 nexthop.  */
  49 };
  50
  51 enum blackhole_type {
  52         BLACKHOLE_UNSPEC = 0,
  53         BLACKHOLE_NULL,
  54         BLACKHOLE_REJECT,
  55         BLACKHOLE_ADMINPROHIB,
  56 };
  57
  58 /* IPV[46] -> IPV[46]_IFINDEX */
  59 #define NEXTHOP_FIRSTHOPTYPE(type)                                             \
  60         ((type) == NEXTHOP_TYPE_IFINDEX || (type) == NEXTHOP_TYPE_BLACKHOLE)   \
  61                 ? (type)                                                       \
  62                 : ((type) | 1)
  63
  64 enum nh_encap_type {
  65         NET_VXLAN = 100, /* value copied from FPM_NH_ENCAP_VXLAN. */
  66 };
  67
  68 /* Nexthop structure. */
  69 struct nexthop {
  70         struct nexthop *next;
  71         struct nexthop *prev;
  72
  73         /*
  74          * What vrf is this nexthop associated with?
  75          */
  76         vrf_id_t vrf_id;
  77
  78         /* Interface index. */
  79         ifindex_t ifindex;
  80
  81         enum nexthop_types_t type;
  82
  83         uint8_t flags;
  84 #define NEXTHOP_FLAG_ACTIVE     (1 << 0) /* This nexthop is alive. */
  85 #define NEXTHOP_FLAG_FIB        (1 << 1) /* FIB nexthop. */
  86 #define NEXTHOP_FLAG_RECURSIVE  (1 << 2) /* Recursive nexthop. */
  87 #define NEXTHOP_FLAG_ONLINK     (1 << 3) /* Nexthop should be installed
  88                                           * onlink.
  89                                           */
  90 #define NEXTHOP_FLAG_DUPLICATE  (1 << 4) /* nexthop duplicates another
  91                                           * active one
  92                                           */
  93 #define NEXTHOP_FLAG_RNH_FILTERED  (1 << 5) /* rmap filtered, used by rnh */
  94 #define NEXTHOP_FLAG_HAS_BACKUP (1 << 6)    /* Backup nexthop index is set */
  95
  96 #define NEXTHOP_IS_ACTIVE(flags)                                               \
  97         (CHECK_FLAG(flags, NEXTHOP_FLAG_ACTIVE)                                \
  98          && !CHECK_FLAG(flags, NEXTHOP_FLAG_DUPLICATE))
  99
 100         /* Nexthop address */
 101         union {
 102                 union g_addr gate;
 103                 enum blackhole_type bh_type;
 104         };
 105         union g_addr src;
 106         union g_addr rmap_src; /* Src is set via routemap */
 107
 108         /* Nexthops obtained by recursive resolution.
 109          *
 110          * If the nexthop struct needs to be resolved recursively,
 111          * NEXTHOP_FLAG_RECURSIVE will be set in flags and the nexthops
 112          * obtained by recursive resolution will be added to `resolved'.
 113          */
 114         struct nexthop *resolved;
 115         /* Recursive parent */
 116         struct nexthop *rparent;
 117
 118         /* Type of label(s), if any */
 119         enum lsp_types_t nh_label_type;
 120
 121         /* Label(s) associated with this nexthop. */
 122         struct mpls_label_stack *nh_label;
 123
 124         /* Weight of the nexthop ( for unequal cost ECMP ) */
 125         uint8_t weight;
 126
 127         /* Index of a corresponding backup nexthop in a backup list;
 128          * only meaningful if the HAS_BACKUP flag is set.
 129          */
 130         uint8_t backup_idx;
 131
 132         /* Encapsulation information. */
 133         enum nh_encap_type nh_encap_type;
 134         union {
 135                 vni_t vni;
 136         } nh_encap;
 137 };
 138
 139 /* Backup index value is limited */
 140 #define NEXTHOP_BACKUP_IDX_MAX 255
 141
 142 /* Utility to append one nexthop to another. */
 143 #define NEXTHOP_APPEND(to, new)           \
 144         do {                              \
 145                 (to)->next = (new);       \
 146                 (new)->prev = (to);       \
 147                 (new)->next = NULL;       \
 148         } while (0)
 149
 150 struct nexthop *nexthop_new(void);
 151
 152 void nexthop_free(struct nexthop *nexthop);
 153 void nexthops_free(struct nexthop *nexthop);
 154
 155 void nexthop_add_labels(struct nexthop *nexthop, enum lsp_types_t ltype,
 156                         uint8_t num_labels, const mpls_label_t *labels);
 157 void nexthop_del_labels(struct nexthop *);
 158
 159 /*
 160  * Allocate a new nexthop object and initialize it from various args.
 161  */
 162 struct nexthop *nexthop_from_ifindex(ifindex_t ifindex, vrf_id_t vrf_id);
 163 struct nexthop *nexthop_from_ipv4(const struct in_addr *ipv4,
 164                                   const struct in_addr *src,
 165                                   vrf_id_t vrf_id);
 166 struct nexthop *nexthop_from_ipv4_ifindex(const struct in_addr *ipv4,
 167                                           const struct in_addr *src,
 168                                           ifindex_t ifindex, vrf_id_t vrf_id);
 169 struct nexthop *nexthop_from_ipv6(const struct in6_addr *ipv6,
 170                                   vrf_id_t vrf_id);
 171 struct nexthop *nexthop_from_ipv6_ifindex(const struct in6_addr *ipv6,
 172                                           ifindex_t ifindex, vrf_id_t vrf_id);
 173 struct nexthop *nexthop_from_blackhole(enum blackhole_type bh_type);
 174
 175 /*
 176  * Hash a nexthop. Suitable for use with hash tables.
 177  *
 178  * This function uses the following values when computing the hash:
 179  * - vrf_id
 180  * - ifindex
 181  * - type
 182  * - gate
 183  *
 184  * nexthop
 185  *    The nexthop to hash
 186  *
 187  * Returns:
 188  *    32-bit hash of nexthop
 189  */
 190 uint32_t nexthop_hash(const struct nexthop *nexthop);
 191 /*
 192  * Hash a nexthop only on word-sized attributes:
 193  * - vrf_id
 194  * - ifindex
 195  * - type
 196  * - (some) flags
 197  */
 198 uint32_t nexthop_hash_quick(const struct nexthop *nexthop);
 199
 200 extern bool nexthop_same(const struct nexthop *nh1, const struct nexthop *nh2);
 201 extern bool nexthop_same_no_labels(const struct nexthop *nh1,
 202                                    const struct nexthop *nh2);
 203 extern int nexthop_cmp(const struct nexthop *nh1, const struct nexthop *nh2);
 204 extern int nexthop_g_addr_cmp(enum nexthop_types_t type,
 205                               const union g_addr *addr1,
 206                               const union g_addr *addr2);
 207
 208 extern const char *nexthop_type_to_str(enum nexthop_types_t nh_type);
 209 extern bool nexthop_labels_match(const struct nexthop *nh1,
 210                                  const struct nexthop *nh2);
 211 extern int nexthop_same_firsthop(struct nexthop *next1, struct nexthop *next2);
 212
 213 extern const char *nexthop2str(const struct nexthop *nexthop,
 214                                char *str, int size);
 215 extern struct nexthop *nexthop_next(const struct nexthop *nexthop);
 216 extern struct nexthop *
 217 nexthop_next_active_resolved(const struct nexthop *nexthop);
 218 extern unsigned int nexthop_level(struct nexthop *nexthop);
 219 /* Copies to an already allocated nexthop struct */
 220 extern void nexthop_copy(struct nexthop *copy, const struct nexthop *nexthop,
 221                          struct nexthop *rparent);
 222 /* Copies to an already allocated nexthop struct, not including recurse info */
 223 extern void nexthop_copy_no_recurse(struct nexthop *copy,
 224                                     const struct nexthop *nexthop,
 225                                     struct nexthop *rparent);
 226 /* Duplicates a nexthop and returns the newly allocated nexthop */
 227 extern struct nexthop *nexthop_dup(const struct nexthop *nexthop,
 228                                    struct nexthop *rparent);
 229 /* Duplicates a nexthop and returns the newly allocated nexthop */
 230 extern struct nexthop *nexthop_dup_no_recurse(const struct nexthop *nexthop,
 231                                               struct nexthop *rparent);
 232
 233 #ifdef _FRR_ATTRIBUTE_PRINTFRR
 234 #pragma FRR printfrr_ext "%pNH"  (struct nexthop *)
 235 #endif
 236
 237 #ifdef __cplusplus
 238 }
 239 #endif
 240
 241 #endif /*_LIB_NEXTHOP_H */