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 #include "srv6.h"
  30
  31 #ifdef __cplusplus
  32 extern "C" {
  33 #endif
  34
  35 /* Maximum next hop string length - gateway + ifindex */
  36 #define NEXTHOP_STRLEN (INET6_ADDRSTRLEN + 30)
  37
  38 union g_addr {
  39         struct in_addr ipv4;
  40         struct in6_addr ipv6;
  41 };
  42
  43 enum nexthop_types_t {
  44         NEXTHOP_TYPE_IFINDEX = 1,  /* Directly connected.  */
  45         NEXTHOP_TYPE_IPV4,       /* IPv4 nexthop.  */
  46         NEXTHOP_TYPE_IPV4_IFINDEX, /* IPv4 nexthop with ifindex.  */
  47         NEXTHOP_TYPE_IPV6,       /* IPv6 nexthop.  */
  48         NEXTHOP_TYPE_IPV6_IFINDEX, /* IPv6 nexthop with ifindex.  */
  49         NEXTHOP_TYPE_BLACKHOLE,    /* Null0 nexthop.  */
  50 };
  51
  52 enum blackhole_type {
  53         BLACKHOLE_UNSPEC = 0,
  54         BLACKHOLE_NULL,
  55         BLACKHOLE_REJECT,
  56         BLACKHOLE_ADMINPROHIB,
  57 };
  58
  59 enum nh_encap_type {
  60         NET_VXLAN = 100, /* value copied from FPM_NH_ENCAP_VXLAN. */
  61 };
  62
  63 /* Fixed limit on the number of backup nexthops per primary nexthop */
  64 #define NEXTHOP_MAX_BACKUPS  8
  65
  66 /* Backup index value is limited */
  67 #define NEXTHOP_BACKUP_IDX_MAX 255
  68
  69 /* Nexthop structure. */
  70 struct nexthop {
  71         struct nexthop *next;
  72         struct nexthop *prev;
  73
  74         /*
  75          * What vrf is this nexthop associated with?
  76          */
  77         vrf_id_t vrf_id;
  78
  79         /* Interface index. */
  80         ifindex_t ifindex;
  81
  82         enum nexthop_types_t type;
  83
  84         uint8_t flags;
  85 #define NEXTHOP_FLAG_ACTIVE     (1 << 0) /* This nexthop is alive. */
  86 #define NEXTHOP_FLAG_FIB        (1 << 1) /* FIB nexthop. */
  87 #define NEXTHOP_FLAG_RECURSIVE  (1 << 2) /* Recursive nexthop. */
  88 #define NEXTHOP_FLAG_ONLINK     (1 << 3) /* Nexthop should be installed
  89                                           * onlink.
  90                                           */
  91 #define NEXTHOP_FLAG_DUPLICATE  (1 << 4) /* nexthop duplicates another
  92                                           * active one
  93                                           */
  94 #define NEXTHOP_FLAG_RNH_FILTERED  (1 << 5) /* rmap filtered, used by rnh */
  95 #define NEXTHOP_FLAG_HAS_BACKUP (1 << 6)    /* Backup nexthop index is set */
  96 #define NEXTHOP_FLAG_SRTE       (1 << 7) /* SR-TE color used for BGP traffic */
  97 #define NEXTHOP_FLAG_EVPN       (1 << 8) /* nexthop is EVPN */
  98
  99 #define NEXTHOP_IS_ACTIVE(flags)                                               \
 100         (CHECK_FLAG(flags, NEXTHOP_FLAG_ACTIVE)                                \
 101          && !CHECK_FLAG(flags, NEXTHOP_FLAG_DUPLICATE))
 102
 103         /* Nexthop address */
 104         union {
 105                 union g_addr gate;
 106                 enum blackhole_type bh_type;
 107         };
 108         union g_addr src;
 109         union g_addr rmap_src; /* Src is set via routemap */
 110
 111         /* Nexthops obtained by recursive resolution.
 112          *
 113          * If the nexthop struct needs to be resolved recursively,
 114          * NEXTHOP_FLAG_RECURSIVE will be set in flags and the nexthops
 115          * obtained by recursive resolution will be added to `resolved'.
 116          */
 117         struct nexthop *resolved;
 118         /* Recursive parent */
 119         struct nexthop *rparent;
 120
 121         /* Type of label(s), if any */
 122         enum lsp_types_t nh_label_type;
 123
 124         /* Label(s) associated with this nexthop. */
 125         struct mpls_label_stack *nh_label;
 126
 127         /* Weight of the nexthop ( for unequal cost ECMP ) */
 128         uint8_t weight;
 129
 130         /* Count and index of corresponding backup nexthop(s) in a backup list;
 131          * only meaningful if the HAS_BACKUP flag is set.
 132          */
 133         uint8_t backup_num;
 134         uint8_t backup_idx[NEXTHOP_MAX_BACKUPS];
 135
 136         /* Encapsulation information. */
 137         enum nh_encap_type nh_encap_type;
 138         union {
 139                 vni_t vni;
 140         } nh_encap;
 141
 142         /* SR-TE color used for matching SR-TE policies */
 143         uint32_t srte_color;
 144
 145         /* SRv6 information */
 146         struct nexthop_srv6 *nh_srv6;
 147 };
 148
 149 /* Utility to append one nexthop to another. */
 150 #define NEXTHOP_APPEND(to, new)           \
 151         do {                              \
 152                 (to)->next = (new);       \
 153                 (new)->prev = (to);       \
 154                 (new)->next = NULL;       \
 155         } while (0)
 156
 157 struct nexthop *nexthop_new(void);
 158
 159 void nexthop_free(struct nexthop *nexthop);
 160 void nexthops_free(struct nexthop *nexthop);
 161
 162 void nexthop_add_labels(struct nexthop *nexthop, enum lsp_types_t ltype,
 163                         uint8_t num_labels, const mpls_label_t *labels);
 164 void nexthop_del_labels(struct nexthop *);
 165 void nexthop_add_srv6_seg6local(struct nexthop *nexthop, uint32_t action,
 166                                 const struct seg6local_context *ctx);
 167 void nexthop_del_srv6_seg6local(struct nexthop *nexthop);
 168 void nexthop_add_srv6_seg6(struct nexthop *nexthop,
 169                            const struct in6_addr *segs);
 170 void nexthop_del_srv6_seg6(struct nexthop *nexthop);
 171
 172 /*
 173  * Allocate a new nexthop object and initialize it from various args.
 174  */
 175 struct nexthop *nexthop_from_ifindex(ifindex_t ifindex, vrf_id_t vrf_id);
 176 struct nexthop *nexthop_from_ipv4(const struct in_addr *ipv4,
 177                                   const struct in_addr *src,
 178                                   vrf_id_t vrf_id);
 179 struct nexthop *nexthop_from_ipv4_ifindex(const struct in_addr *ipv4,
 180                                           const struct in_addr *src,
 181                                           ifindex_t ifindex, vrf_id_t vrf_id);
 182 struct nexthop *nexthop_from_ipv6(const struct in6_addr *ipv6,
 183                                   vrf_id_t vrf_id);
 184 struct nexthop *nexthop_from_ipv6_ifindex(const struct in6_addr *ipv6,
 185                                           ifindex_t ifindex, vrf_id_t vrf_id);
 186 struct nexthop *nexthop_from_blackhole(enum blackhole_type bh_type,
 187                                        vrf_id_t nh_vrf_id);
 188
 189 /*
 190  * Hash a nexthop. Suitable for use with hash tables.
 191  *
 192  * This function uses the following values when computing the hash:
 193  * - vrf_id
 194  * - ifindex
 195  * - type
 196  * - gate
 197  *
 198  * nexthop
 199  *    The nexthop to hash
 200  *
 201  * Returns:
 202  *    32-bit hash of nexthop
 203  */
 204 uint32_t nexthop_hash(const struct nexthop *nexthop);
 205 /*
 206  * Hash a nexthop only on word-sized attributes:
 207  * - vrf_id
 208  * - ifindex
 209  * - type
 210  * - (some) flags
 211  */
 212 uint32_t nexthop_hash_quick(const struct nexthop *nexthop);
 213
 214 extern bool nexthop_same(const struct nexthop *nh1, const struct nexthop *nh2);
 215 extern bool nexthop_same_no_labels(const struct nexthop *nh1,
 216                                    const struct nexthop *nh2);
 217 extern int nexthop_cmp(const struct nexthop *nh1, const struct nexthop *nh2);
 218 extern int nexthop_g_addr_cmp(enum nexthop_types_t type,
 219                               const union g_addr *addr1,
 220                               const union g_addr *addr2);
 221
 222 /* More-limited comparison function used to detect duplicate nexthops.
 223  * Returns -1, 0, 1
 224  */
 225 int nexthop_cmp_basic(const struct nexthop *nh1, const struct nexthop *nh2);
 226
 227 extern const char *nexthop_type_to_str(enum nexthop_types_t nh_type);
 228 extern bool nexthop_labels_match(const struct nexthop *nh1,
 229                                  const struct nexthop *nh2);
 230
 231 extern const char *nexthop2str(const struct nexthop *nexthop,
 232                                char *str, int size);
 233 extern struct nexthop *nexthop_next(const struct nexthop *nexthop);
 234 extern struct nexthop *
 235 nexthop_next_active_resolved(const struct nexthop *nexthop);
 236 extern unsigned int nexthop_level(const struct nexthop *nexthop);
 237 /* Copies to an already allocated nexthop struct */
 238 extern void nexthop_copy(struct nexthop *copy, const struct nexthop *nexthop,
 239                          struct nexthop *rparent);
 240 /* Copies to an already allocated nexthop struct, not including recurse info */
 241 extern void nexthop_copy_no_recurse(struct nexthop *copy,
 242                                     const struct nexthop *nexthop,
 243                                     struct nexthop *rparent);
 244 /* Duplicates a nexthop and returns the newly allocated nexthop */
 245 extern struct nexthop *nexthop_dup(const struct nexthop *nexthop,
 246                                    struct nexthop *rparent);
 247 /* Duplicates a nexthop and returns the newly allocated nexthop */
 248 extern struct nexthop *nexthop_dup_no_recurse(const struct nexthop *nexthop,
 249                                               struct nexthop *rparent);
 250
 251 /*
 252  * Parse one or more backup index values, as comma-separated numbers,
 253  * into caller's array of uint8_ts. The array must be NEXTHOP_MAX_BACKUPS
 254  * in size. Mails back the number of values converted, and returns 0 on
 255  * success, <0 if an error in parsing.
 256  */
 257 int nexthop_str2backups(const char *str, int *num_backups,
 258                         uint8_t *backups);
 259
 260 #ifdef _FRR_ATTRIBUTE_PRINTFRR
 261 #pragma FRR printfrr_ext "%pNH"  (struct nexthop *)
 262 #endif
 263
 264 ssize_t printfrr_nhs(struct fbuf *buf, const struct nexthop *nh);
 265 #ifdef __cplusplus
 266 }
 267 #endif
 268
 269 #endif /*_LIB_NEXTHOP_H */