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 /* Fixed limit on the number of backup nexthops per primary nexthop */
  69 #define NEXTHOP_MAX_BACKUPS  8
  70
  71 /* Backup index value is limited */
  72 #define NEXTHOP_BACKUP_IDX_MAX 255
  73
  74 /* Nexthop structure. */
  75 struct nexthop {
  76         struct nexthop *next;
  77         struct nexthop *prev;
  78
  79         /*
  80          * What vrf is this nexthop associated with?
  81          */
  82         vrf_id_t vrf_id;
  83
  84         /* Interface index. */
  85         ifindex_t ifindex;
  86
  87         enum nexthop_types_t type;
  88
  89         uint8_t flags;
  90 #define NEXTHOP_FLAG_ACTIVE     (1 << 0) /* This nexthop is alive. */
  91 #define NEXTHOP_FLAG_FIB        (1 << 1) /* FIB nexthop. */
  92 #define NEXTHOP_FLAG_RECURSIVE  (1 << 2) /* Recursive nexthop. */
  93 #define NEXTHOP_FLAG_ONLINK     (1 << 3) /* Nexthop should be installed
  94                                           * onlink.
  95                                           */
  96 #define NEXTHOP_FLAG_DUPLICATE  (1 << 4) /* nexthop duplicates another
  97                                           * active one
  98                                           */
  99 #define NEXTHOP_FLAG_RNH_FILTERED  (1 << 5) /* rmap filtered, used by rnh */
 100 #define NEXTHOP_FLAG_HAS_BACKUP (1 << 6)    /* Backup nexthop index is set */
 101
 102 #define NEXTHOP_IS_ACTIVE(flags)                                               \
 103         (CHECK_FLAG(flags, NEXTHOP_FLAG_ACTIVE)                                \
 104          && !CHECK_FLAG(flags, NEXTHOP_FLAG_DUPLICATE))
 105
 106         /* Nexthop address */
 107         union {
 108                 union g_addr gate;
 109                 enum blackhole_type bh_type;
 110         };
 111         union g_addr src;
 112         union g_addr rmap_src; /* Src is set via routemap */
 113
 114         /* Nexthops obtained by recursive resolution.
 115          *
 116          * If the nexthop struct needs to be resolved recursively,
 117          * NEXTHOP_FLAG_RECURSIVE will be set in flags and the nexthops
 118          * obtained by recursive resolution will be added to `resolved'.
 119          */
 120         struct nexthop *resolved;
 121         /* Recursive parent */
 122         struct nexthop *rparent;
 123
 124         /* Type of label(s), if any */
 125         enum lsp_types_t nh_label_type;
 126
 127         /* Label(s) associated with this nexthop. */
 128         struct mpls_label_stack *nh_label;
 129
 130         /* Weight of the nexthop ( for unequal cost ECMP ) */
 131         uint8_t weight;
 132
 133         /* Count and index of corresponding backup nexthop(s) in a backup list;
 134          * only meaningful if the HAS_BACKUP flag is set.
 135          */
 136         uint8_t backup_num;
 137         uint8_t backup_idx[NEXTHOP_MAX_BACKUPS];
 138
 139         /* Encapsulation information. */
 140         enum nh_encap_type nh_encap_type;
 141         union {
 142                 vni_t vni;
 143         } nh_encap;
 144 };
 145
 146 /* Utility to append one nexthop to another. */
 147 #define NEXTHOP_APPEND(to, new)           \
 148         do {                              \
 149                 (to)->next = (new);       \
 150                 (new)->prev = (to);       \
 151                 (new)->next = NULL;       \
 152         } while (0)
 153
 154 struct nexthop *nexthop_new(void);
 155
 156 void nexthop_free(struct nexthop *nexthop);
 157 void nexthops_free(struct nexthop *nexthop);
 158
 159 void nexthop_add_labels(struct nexthop *nexthop, enum lsp_types_t ltype,
 160                         uint8_t num_labels, const mpls_label_t *labels);
 161 void nexthop_del_labels(struct nexthop *);
 162
 163 /*
 164  * Allocate a new nexthop object and initialize it from various args.
 165  */
 166 struct nexthop *nexthop_from_ifindex(ifindex_t ifindex, vrf_id_t vrf_id);
 167 struct nexthop *nexthop_from_ipv4(const struct in_addr *ipv4,
 168                                   const struct in_addr *src,
 169                                   vrf_id_t vrf_id);
 170 struct nexthop *nexthop_from_ipv4_ifindex(const struct in_addr *ipv4,
 171                                           const struct in_addr *src,
 172                                           ifindex_t ifindex, vrf_id_t vrf_id);
 173 struct nexthop *nexthop_from_ipv6(const struct in6_addr *ipv6,
 174                                   vrf_id_t vrf_id);
 175 struct nexthop *nexthop_from_ipv6_ifindex(const struct in6_addr *ipv6,
 176                                           ifindex_t ifindex, vrf_id_t vrf_id);
 177 struct nexthop *nexthop_from_blackhole(enum blackhole_type bh_type);
 178
 179 /*
 180  * Hash a nexthop. Suitable for use with hash tables.
 181  *
 182  * This function uses the following values when computing the hash:
 183  * - vrf_id
 184  * - ifindex
 185  * - type
 186  * - gate
 187  *
 188  * nexthop
 189  *    The nexthop to hash
 190  *
 191  * Returns:
 192  *    32-bit hash of nexthop
 193  */
 194 uint32_t nexthop_hash(const struct nexthop *nexthop);
 195 /*
 196  * Hash a nexthop only on word-sized attributes:
 197  * - vrf_id
 198  * - ifindex
 199  * - type
 200  * - (some) flags
 201  */
 202 uint32_t nexthop_hash_quick(const struct nexthop *nexthop);
 203
 204 extern bool nexthop_same(const struct nexthop *nh1, const struct nexthop *nh2);
 205 extern bool nexthop_same_no_labels(const struct nexthop *nh1,
 206                                    const struct nexthop *nh2);
 207 extern int nexthop_cmp(const struct nexthop *nh1, const struct nexthop *nh2);
 208 extern int nexthop_g_addr_cmp(enum nexthop_types_t type,
 209                               const union g_addr *addr1,
 210                               const union g_addr *addr2);
 211
 212 extern const char *nexthop_type_to_str(enum nexthop_types_t nh_type);
 213 extern bool nexthop_labels_match(const struct nexthop *nh1,
 214                                  const struct nexthop *nh2);
 215 extern bool nexthop_same_firsthop(const struct nexthop *next1,
 216                                   const struct nexthop *next2);
 217
 218 extern const char *nexthop2str(const struct nexthop *nexthop,
 219                                char *str, int size);
 220 extern struct nexthop *nexthop_next(const struct nexthop *nexthop);
 221 extern struct nexthop *
 222 nexthop_next_active_resolved(const struct nexthop *nexthop);
 223 extern unsigned int nexthop_level(const struct nexthop *nexthop);
 224 /* Copies to an already allocated nexthop struct */
 225 extern void nexthop_copy(struct nexthop *copy, const struct nexthop *nexthop,
 226                          struct nexthop *rparent);
 227 /* Copies to an already allocated nexthop struct, not including recurse info */
 228 extern void nexthop_copy_no_recurse(struct nexthop *copy,
 229                                     const struct nexthop *nexthop,
 230                                     struct nexthop *rparent);
 231 /* Duplicates a nexthop and returns the newly allocated nexthop */
 232 extern struct nexthop *nexthop_dup(const struct nexthop *nexthop,
 233                                    struct nexthop *rparent);
 234 /* Duplicates a nexthop and returns the newly allocated nexthop */
 235 extern struct nexthop *nexthop_dup_no_recurse(const struct nexthop *nexthop,
 236                                               struct nexthop *rparent);
 237
 238 /*
 239  * Parse one or more backup index values, as comma-separated numbers,
 240  * into caller's array of uint8_ts. The array must be NEXTHOP_MAX_BACKUPS
 241  * in size. Mails back the number of values converted, and returns 0 on
 242  * success, <0 if an error in parsing.
 243  */
 244 int nexthop_str2backups(const char *str, int *num_backups,
 245                         uint8_t *backups);
 246
 247 #ifdef _FRR_ATTRIBUTE_PRINTFRR
 248 #pragma FRR printfrr_ext "%pNH"  (struct nexthop *)
 249 #endif
 250
 251 #ifdef __cplusplus
 252 }
 253 #endif
 254
 255 #endif /*_LIB_NEXTHOP_H */